Boiler Operation Manual QN1 SEC G 04 TP 003(239)

QUANG NINH THERMAL POWER JOINT STOCK COMPANY 2×300 MW

SEC BOILER & AUXILIARIES OPERATION MANUAL

QUANG NINH THERMAL POWER JOINT STOCK COMPANY

2 × 300 MW – Anthracite Coal Fired Power Station

Boiler & Auxiliaries

Operation Manual

Date: 2008-09-15 No.:QN1-SEC-G-04-TP-003 Rev. : A



Index

1 SCOPE ..................................................................................................................................................... 4

2 SPECIFIC QUOTING DOCUMENTS .................................................................................................... 4

3 BOILER TECHNIQUE SPECIFICATION.............................................................................................. 5

3.1 INTRODUCTION OF BOILER .................................................................................................................. 5

3.2 BOILER NAMEPLATE ............................................................................................................................ 7

3.3 BOILER DESIGN INFORMATION ............................................................................................................ 8

3.4 REQUIREMENT FOR QUALITY OF BOILER STEAM............................................................................... 16

3.5 BOILER AUXILIARY EQUIPMENT TECHNICAL SPECIFICATIONS ............................................................ 19

4 BOILER AND INTERLOCK PROTECTION VALUE AUXILIARY EQUIPMENT........................... 34

4.1 BOILER PROTECTING LIMIT VALUE .................................................................................................... 34

4.2 BOILER AUXILIARY INTERLOCK PROTECTION VALUE AUXILIARY EQUIPMENT. ................................... 35

5 START-UP.............................................................................................................................................. 44

5.1 BASIC REGULAR ................................................................................................................................ 44

5.2 REPAIR TEST AND ACCEPTANCE INSPECTION ...................................................................................... 44

5.3 CHECK AND PREPARATION BEFORE START-UP..................................................................................... 70

5.4 COLD START-UP SEQUENCE ................................................................................................................ 74

5.5 HOT START-UP .................................................................................................................................... 83

5.6 PARAMETER CONTROL VALUE IN THE PROCESS OF START-UP ............................................................. 87

6 MONITORING AND ADJUSTMENT IN BOILER OPERATION ...................................................... 88

6.1 THE MAIN TASK AND OBJECTIVES OF OPERATION ADJUSTMENT ......................................................... 88

6.2 MAIN PARAMETER AND LIMIT OF OPERATION CONTROL .................................................................... 88

6.3 CHECKING, MONITORING AND MAINTENANCE IN BOILER OPERATION ................................................ 91

Date: 2008-09-15 No.:QN1-SEC-G-04-TP-003 Page 1 Rev. : A



6.4 BOILER OPERATION MEASURE CONTROL.......................................................................................... 100

7 SHUT-DOWN OF BOILER................................................................................................................. 100

7.1 BASIC REGULAR (GENERALS ) .......................................................................................................... 100

7.2 PREPARATION BEFORE SHUT-DOWN OF BOILER ................................................................................ 101

7.3 SHUT-DOWN WITH SLIDING PARAMETER (NEED COOLING ) .............................................................. 102

7.4 NORMAL SHUT-DOWN (HOT STAND-BY ) .......................................................................................... 104

7.5 EMERGENCY SHUT-DOWN ................................................................................................................ 105

7.6 SHUT-DOWN MAINTENANCE ............................................................................................................ 105

8 BOILER AUXILIARY EQUIPMENT ..................................................................................................113

8.1 BASIC REGULAR OF AUXILIARY EQUIPMENT OPERATION.................................................................. 113

8.2 MOTOR OPERATION .......................................................................................................................... 117

8.3 START-UP, STOP AND OPERATIONAL MAINTENANCE OF AUXILIARY EQUIPMENT AND SYSTEM .......... 117

9 PERIODIC WORK, TEST AND SHIFTING OF THE BOILER AND RELEVANT AUXILIARY

EQUIPMENT............................................................................................................................................. 171

10 ACCIDENTS PROCESSING OF BOILER......................................................................................... 172

10.1 BASIC PRINCIPIA OF ACCIDENTS PROCESSING ................................................................................. 172

10.2 BOILER EMERGENCY SHUTDOWN .................................................................................................... 174

10.3 SHUTDOWN APPLICATION OF BOILER .............................................................................................. 178

10.4 BOILER ABNORMAL OPERATION PARAMETER ................................................................................. 178

10.5 LOAD REJECTION OF UNIT ............................................................................................................... 183

10.6 AUXILIARY POWER SUPPLY INTERRUPTION ..................................................................................... 184

10.7 CONTROL&INSTRUMENT AND APPARATUS POWER SUPPLY INTERRUPTION .................................... 185

10.8 FIRE ACCIDENT ................................................................................................................................ 186

10.9 PROCESSING INFERIOR QUALITY OF WATER AND STEAM ................................................................ 188

10.10 BOILER HEATING SURFACE SLAGGING SERIOUSLY...................................................................... 190




10.11 GAS DUCT REBURNING................................................................................................................ 191

10.12 UNIT TRIP .................................................................................................................................... 192

10.13 STEAM DRUM FULL FEEDED........................................................................................................ 194

10.14 STEAM DRUM SHORT FEEDED ..................................................................................................... 195

10.15 PRIMING....................................................................................................................................... 197

10.16 HIGH FURNACE PRESSURE ........................................................................................................... 197

10.17 LOW FURNACE PRESSURE............................................................................................................ 198

10.18 BOILER BURNING OUT................................................................................................................. 199

10.19 FUEL TRIP .................................................................................................................................... 200

10.20 WATER WALL TUBES TXPLOSION................................................................................................. 201

10.21 ECONOMIZER TUBES EXPLOSION................................................................................................. 202

10.22 SUPERHEATER TUBES EXPLOSION ............................................................................................... 203

10.23 REHEATER TUBES EXPLOSION ..................................................................................................... 204

10.24 THE BREAK OF STEAM PIPES OR FEEDWATER PIPES OUTSIDE THE BOILER ................................. 205

10.25 HIGH STEAM DRUM PRESSURE .................................................................................................... 206

10.26 AUXILIARY FAILURE .................................................................................................................... 208

11 APPENDIX .......................................................................................................................................... 232

11.1 THE CONTRASTIVE LIST OF THE ABSOLUTE PRESSURE AND TEMPERATURE IN SATURATED STATES .. 232

11.2 BOILER COLD START-UP CURVE ....................................................................................................... 233

11.3 BOILER HOT STAR-TUP CURVE......................................................................................................... 234

11.4 BOILER DRUME LEVEL VS LOAD CURVE........................................................................................... 237

11.5 BOILER O2 IN FLUE GAS VS LOAD CURVE ........................................................................................ 238




1 Scope

This operating & maintenance manual provides the principle, methods and

steps of the start-up, shut-down, operating & maintenance, control and adjustment of the

boiler for Vietnam Quang Ninh 2×300MW Project. All the staff engaged in operating

equipment maintenance and management of manufacture and production technology

management in Quang Ninh power plant should be familiar with all or relevant parts of the manual

and execute extremely strictly.

2 Specific Quoting Documents

The items included in the following Chinese standards are made of the items of this manual

by citing it. When this manual was promulgated, all the standards in it are valid

and will be revised .The parties using the manual should explore the possibility

of the latest version of following standard which will be decided whether to apply to this

standard. Besides the following standards, when the equipment manufacturer has the special

requirement which meets the safety operation standards, the special requirement from

the equipment manufacturer should be complied with.

No.

Standard Code Standard Name

01 DL/T 607-1996

300MW turbine operation guidelines

02 DL/T 611－1996 300MW boiler operation guidelines

03 DL/T 612－1996

Monitoring regular of power industry boiler and pressure vessel

04

DAS(1994)277 Working regulation of power safety

(Thermal mechanical parts)

05

DL408-91

Working regulation of power safety (power plants and substations parts)

06 DL558-94 Investigation of production accidents in power industry

07

DL435-91 Explosion-proof of furnace regular for thermal Power Plant

pulverized coal-fired boiler

08 DL/T 561－95

Vapor and chemical monitoring guidelines of thermal

power plant

09

GB/T 12145-1999 The quality of vapor of thermal power generating units and

steam power equipment

Date: 2008-09-15 No.: QN1-SEC-G-04-TP-003 Page 4 Rev. : A



10

SD223-87 Anti-corrosion guidelines of stand-thermal power plant

equipment

11 GB7596-87 Oil quality standards in turbine in the operation of power plant

12

GDF(2000)589

25 pieces of key requirement to prevent major

accidents in power production

13 Design information and equipment information of manufacturer

3 Boiler Technique Specification

3.1 Introduction of Boiler

This boiler is designed by Alstom who provides performance-test technique support .It is

manufactured by Shanghai Boiler Works Ltd. This form of boiler is double-

arched,

W-flame with single furnace, then one middle reheat, control circulation and sub-critical

steam drum furnace. Two units are equipped with one start-up boiler for steam source.

Design coal for boiler is anthracite which is from Vietnam CAM PHA and HON GAI

mining areas.

Combustion system: the system adopts hot air feeding, each boiler with 16 duplex-type

feeders, 32 pulverized coal burner. The capacity of pulverized coal

combustions is

100% BMCR with design-coal. Start-up and stable combustion adopt

heavy oil according to TCVN 6239-2002 standards. This boiler adopts two-

stage ignition. The high-energy igniter ignites the HPO burner and then

the heavy-oil burner ignites pulverized coal. Fuel oil burners will be steam

atomized. This project set 2×5000 tons tank and 2 unloading fuel pumps, two 100%

capacity AC, DC supply pump, 1 dirty oil pump and 1 sewage pump. Oil burning

system arranges oil supply pipe and oil return pipe to boiler burners according to oil

supply and return single piping circulation.

Oil burners: Each arch nose has 8 HFO burners, namely each boiler has 16 burners.

The auxiliary steam which pressure is constantly 5.25 bar (g) makes HFO atomization

and also cleans the burners.HFO will be ignited by high-energy igniter.

Each HFO burner will be equipped with specialized flame detector. Cooling wind will

be provided through two separate specialized circuit burner and the flame

detector .When oil burner

is stopped, it will exit from burner quarrel by about 330 mm to avoid impact of radiation

(prevent the burners from damaged). Low heat value (LHV value) is fuel heat input at

30% BMCR by adopting 12 burners to achieve the burning capacity at 30% BMCR (two



burners in each arch nose are stopped operation).The adjustment ratio of burner is 1:5




using J11 burner.

Flue and air system, pulverized coal system: flue and air system adopts balance draft,

the flue gas will be discharged to the atmosphere passing ESP and

then FGD, or directly to the atmosphere passing the FGD bypass.

Force draft-fan and induced draft-fan is axial flow fan. FDF is moving

blade adjustable and IDF is static blade adjustable. Milling system bin and

flue gas drying milling system with balance draft. Each boiler is equipped

with 2 single way BBI globe mill. Primary air fan adopts centrifugal

fan .The vent will be filtrated pulverized coal through cloth dust collector and then

discharged to atmosphere through vent fan.

Ash slag removal and ash yard: Adopting dry ash extraction ash at the bottom is

discharged to slag pool through slag crusher and hydro ejector .The fly ash

collected from AP. economizer and ESP is sent to the large ash silo(total 2

ash silo ,each has 2500 m3 volume), the dry ash is further dealt with through the ash-

water mixture and transported to ash pool and then transported to ash

silo through ash emulsion pump (the method for retaining and comprehensive

utilization of dry ash)；

Desulphurization and dust removal system: Choose 4 ESP. This project sets up one

200m-high two-steel cylindrical chimney and also sets up 100% capacity

scrubber adopting Limestone - gypsum wet desulphurization process and GGH；

Compressed air system: total three 50% capacity compressors

considering little lubrication oil.

Safety valve: This boiler is equipped with 8 spring safety valves supplied

by Crosby America ,who are located in the following places: 3 valves at the drum, 1

valve at SH outlet piping, 2 valves at RH outlet piping, 2 valves at

RH outlet piping, one electromagnetic relief valve is mounted on SH

outlet piping. The valve is VTI brand supplied by Crosby America. BMCR is

995t/h, the total discharging capacity of drum safety valves is 881.796,

amounting to 88.62 percent of BMCR. The discharging capacity of SH

safety valves is 153.86t/h, amounting to 15.46 percent of BMCR. The discharging

capacity of SH and drum safety valves is 1035.656t /h, amounting to

104.09% percent of BMCR. Max RH steam flow is 848.6t/h. The discharging capacity of

safety valves at RH inlet is 512.94t/h, amounting to 60.45 percent of Max RH steam flow.

The discharging capacity of safety valves at RH outlet is 379.157t/h, amounting to 44.68

percent of Max RH steam flow, The aggregate of discharge capacity at RH outlet and



inlet is 892.097t/h, amounting to 105.13 percent of the Max RH steam

flow. The




discharging capacity of electromagnetic Relief Valve is 166t/h, amounting to 16.68%

percent of BMCR, It is not included in Safety Valve capacity whatsoever.

3.2 Boiler Nameplate

Type of boiler Unit SG-995/17.5-M728

Manufacturer SBWL

Fabrication no. 728-1-8069

Boiler form

Double-arched, W-flame with single

furnace, then a middle reheat,

control circulation and sub-critical steam

drumBoiler maximum continues rating(B －

MCR)

t/h

995

Continues rating(RO) t/h 889.1

Rated temp. of main steam(B-MCR／RO) ℃ 541／541

Rated pressure of main steam B-MCR／

RO)

M Pa·g

17.29／17.13

Reheater steam flow(B-MCR／RO) t/h 882.498/736.407

Temp of reheater inlet／outlet(B-MCR) ℃ 320/540

Temp of reheater inlet／outlet(RO) ℃ 309/540

Pressure of reheater inlet／outlet(B-MCR) MPa·g 3.53/3.34

Pressure of reheater inlet／outlet(RO) MPa·g 3.14/2.98

Temp of feed water (B-MCR／RO) ℃ 281/273

Date of starting erection

Date of starting manufacture




3.3 Boiler Design Information

3.3.1 Water Bulk of Boiler Pressure Parts

No. System Pressure Units Date Total

1 Drum m3 40

2 Water wall m3 82

3

Primary system Superheater

economizer and

header and other

connecting pipe

m3

151

273

4 Reheater m3 48

5

Secondary system Header and

connecting pipe

m3

24

72

3.3.2 Boiler Safety Valve Setting Pressure and Discharge

Set pressure

Desi

gn

temp

N o.

Location

Type of valve

Specificat

ion

(inch)

Openi ng MPa

Blo w

dow n MPa

Blow

down

Different

ial

pressur

e%

Dischargi

ng

capacity

t/h

℃

1

DRUM

HE-96W

3 M2 6

20.50

19.8

9

3

291.697

369

2

DRUM

HE-96W

3 M2 6

20.60

19.7

8

4

293.924

369

3

DRUM

HE-96W

3 M2 6

20.70

19.6

7

5

296.175

369

4

Reaheate

r outlet

HCI-98W

3 L2 6

18.70

18.1

4

3

153.860

557

5

Reaheate

r outlet

HCI-46W

6 RR10

4.50

4.37

3

253.574

313

6

Reaheate

r outlet

HCI-46W

6 RR10

4.60

4.46

3

259.366

313

7

Reaheate

r outlet

HCI-48W

6 RR10

4.10

3.98

3

187.347

554




8 Reaheate

r outlet

HCI-48W

6 RR10

4.20

4.07

3

191.810

554

9

Superhea

ter

outlet(ER

V)

E0L121N7BWR

A5P1

2..5″×4″

18.50

18.1

3

2

166

557

3.3.3 Thermal Performance Calculation for Boiler Operation

Coal combustion(loads)

Items

Unit

BMCR

RO

75%

RO

60%

RO

Minmum

loads

*60% RO

1. Total output of Generator MW 300 225 210

2. Steam flow kg/H

(a) Reheater outlet 995 882.7 639.4 518.9

(b) High-pressure turbin inlet 995 882.7 639.4 518.9

(c) High-pressure turbin

Exhaust

822.5

735.3

543.0

443.8

(d) Mid-pressure turbin inlet 849.4 756.5 555.0 443.8

3. Steam pressure kg/cm2g

(a) Drum 190.4 186.5 156 127.5

(b) Superheater outlet 176.3 174.7 149 121.9

(c) High-pressure turbin inlet 169 169 145.5 119.1

(d) High-pressure turbin

Exhaust

37.6

33.6

24.7

20.0

(e) Mid-pressure turbin inlet 33.7 30.1 22.1 18.0

4. Steam temp. ℃

(a) Drum 362 360 347 333

(b) Superheater outlet 541 540 539 539

(c) High-pressure turbin inlet 538 538 538 538

(d) High-pressure turbin

Exhaust

323

312

301

304

(e) Mid-pressure turbin inlet 538 538 538 538

5. Feedwater pressure kg/cm2g

(a) BFP outlet




(b) High-pressure heaters

outlet

(c) Economizer inlet 193.9 189.4 158.7 129.9

(d) Economizer outlet 193.4 189.0 158.5 129.8

6. Temp. of feedwater ℃

(a) Feedwater pump outlet

(b) Economizer inlet 281 273 254 243

(c) Economizer outlet 299 291 275 267

7. Heat loss (high heating

l )

%

(a) Heat in the dry flue gas

(L ')

4.19

3.88

(b) Moisture in fuel (L2') 1.13 1.12

(c) The water generated

from the hydrogen

combustion in

2.36

2.34

(d) The moisture in the

air((L4')

0.11

0.12

(e) Un-burned carbon ((L5') 3.00 3.00

(f) The formation of carbon

id ((L ')

(g) Heat loss due to radiation

((L )

0.20

0.26

(h) Other((L8) 0.25 0.25

(i) Manufacturing allowance

((L9)

0.50

0.50

Total(ΣL) 11.75 11.48

(j) Ambient air temperature ℃ 24 24 24 24

(k) Relative Humidity % 80 80 80 80

(l) Atmospheric pressure kg/cm2 1.0332 1.033 1.0332 1.033 1.0332

8. Total heat efficiency % 88.25 88.52

9. Fuel consumption (coal) kg/H 129500 99100

10. Heat kcal/kg

(a) LHV of coal 4815 4815 4815 4815 4815




(b) HHV of coal 4980 4980 4980 4980 4980

11. Furnace heat absorption

(total heat release)

(a) Per Effective volume

x 103

kcal/m3H

86.9

78.5

59.3

49.9

(b) Per Flat area

x 106

kcal/m2H

2.9

2.6

1.95

1.65

(c) Per effective protruding

radiation surface

x 103

kcal/m2H

163.1

147.4

111.2

93.7

12. Air temp. ℃

(a) Steam heater inlet 29 29 29 29

(b) Steam heater outlet 29 29 29 29

(c) Air preheter inlet primary

i

31

31

31

31

(d) Air preheter inlet

secondary air

29

29

29

29

(e) Air preheter outlet primary

air

356

352

324

308

(f) Air preheter outlet

secondary air

333

333

311

297

(g) Mill entrance 580 580 580 580

(h) Mill export 110 110 110 110

13. Gas Temperature ℃

(a) Furnace outlet 1015 990 910 860

(b) Superheater inlet 825 800 730 700

(c) Superheater outlet 670 650 610 580

(d) Air preheter inlet 400 392 358 340

(e) Air preheter outlet

(Un-corrected) 131 127 118 109

(Corrected) 124 121 111 102

14. Dew-point of air preheter

tl t

76

TBA

TBA

TBA

TBA

15. Temp of cold end metal of

AP.

80

77

72

69




16. Flue gas volume 103 kg/H

(a) Economizer outlet 1332 1205 936 827

(b) air preheater outlet 1422 1291 1020 910

17. Combustion air volume 103 kg/H 1216 1101 864 765

18. Maximum speed of flue gas

flow in convection section

M/s

11.2

9.8

7.2

6.2

19. Ash content of economizer

outlet

103 kg/H

41.7

37.8

28.7

24.1

20. Excess air % Vol

(a) Furnace outlet 24 24 28 35

(b) Economizer outlet 25 25 29.5 37

(c) Air preheater outlet 34.4 34.9 42 52

(d) ESP outlet

21. O2 % Vol

(a) Furnace outlet 3.8 3.8 4.3 5.2

(b) Economizer outlet 4.0 4.0 4.5 5.4

(c) Air preheater outlet 5.1 5.1 5.9 6.8

(d) ESP outlet

22. CO2 % Vol

(a) Furnace outlet 14.4 14.4 14.0 13.3

(b) Economizer outlet 14.3 14.3 13.8 13.1

(c) Air preheater outlet 13.4 13.3 12.7 11.9

(d) ESP outlet

23. Heat absorption

x 106

kcal/H

(a) Furnace 264.7 249.2 202.4 172

(b) Superheater 225.0 195.2 139.9 116.8

(c) Reheater 116.5 106.1 77.8 64.3

(d) Economizer 28.5 24.6 19.3 17.1

Total 634.3 575.1 439.4 370.2

(e) Air preheater TBA TBA TBA TBA

(f) Steam air heater 0.0 0.0 0.0 0.0

24. The heat intensity of

heating surface

x103

kcal/m2H




(a) Furnace TBA TBA TBA TBA

(b) Superheater TBA TBA TBA TBA

(c) Reheater TBA TBA TBA TBA

(d) Economizer TBA TBA TBA TBA

(e) Air preheater TBA TBA TBA TBA

3.3.4 Characteristics of Fuel(coal)

No. Symbol Unit Range Date

Heat value

High heat value HHV Kcal/kg 4680-5300 4980

I

Low heat value LHV Kcal/kg 4490-5157 4790

II Analysis

1 Total Moisture(as received) War % 5.55-12.0 9.00

2 Free moisture Ws % 4.81-9.88 7.63

3 Inherent Moisture Win % 0.78-2.35 1.48

4 Moisture in the air dried sample Wad % 0.80-2.41 1.39

5 Fixed carbon (as received) Cfar % 49.54-63.15 53.68

6 Volatile matter(as received) Var % 5.82-8.61 6.83

7 Ash content(air dried basis) Ad % 28.0-37.36 33.5

8 Ash content(as received) Aar % 25.48-34.0 30.49

Total 100.00

III Element analysis

1 C(ADB) Car % 46.83-63.75 54.62

2 H(ADB) Har % 2.56-2.97 2.62

3 O(ADB) Oar % 1.66-2.68 2.09

4 N(ADB) Nar % 0.73-0.86 0.77

5 S(ADB) Saror % 0.27-0.66 0.41

6 A(ADB) Aar % 25.48-34.0 30.49

7 M(ADB) War % 5.55-12.0 9.00

Total 100

IV Physical characteristics

1 Hardness, grindability index - - 45-70 47

2 Pulverized coal particle size

(0-15 mm)

- - - 100

+10mm % 6.16-17.5 10.53




5-10mm % 9.89-18.3 14.22

2.5-5mm % 15.60-21.71 18.62

1.25-2.5mm % 8.73-13.76

0.63-1.25mm % 12.36-18.13 14.89

0.315-0.63mm % 6.80-14.45 10.02

-0.315mm % 11.47-31.47 20.77

3 Density - 0.92-1.10 1.00

4 static angle ° 33-39 37

3.3.5 Characteristics of Burning(ash)

No. Components Symbol Unit Range Design date

Ash components

1 SiO2 % 57.60-64.10 62.83

2 Al2O3 % 23.3-28.64 24.76

3 Fe2O3 % 4.26-6.16 5.41

4 V2O5 % 0.018-0.028 0.026

5 TiO2 % 0.50-0.91 0.68

6 CaO % 0.30-0.77 0.44

7 MgO % 0.67-1.42 1.11

8 K2O % 3.35-4.70 3.64

9 Na2O % 0.15-0.55 0.48

10 P2O5 % 0.19-0.30 0.24

11 SO3 % 0.251-0.481 0.341

12 MnO % 0.006-0.050 0.043

13 Other % 0.00 0.00

Total 100.00

Ash physical characteristic

1 Ash density g/cm3 0.224 - 0.370 0.291

2 FYI R cm 301x102 - 603x102 525x102

Solubility of ash

1 Initial deformation

temperature

T1

0C

1210 - 1280

1250

2

Hemispherical softening

temp.

T2

0C

1430 - 1600

1570

3 Fluid temp. T3 0C 0C 1530 - 1600




Date Characteristics

No.1 No.2A No.2B No.3

Test method

Density at 15℃ mt/m3 =<

0.965

=< 0.991

=< 0.991

=< 0.991

TCVN 6594:200

(ASTMD1298)

Viscosity at 50℃

cSt

=<87

=<180

=<180

=<380

ASTM D445

Sulphur content, by

weight

=<2.0%

=<2.0%

=<3.0%

=<3.5%

TCVN67O1:200O

(ASTM

Pour point ℃

=<+12

=<+24

=<+24

=<+24

TCVN3753:1995 ASTM

D97 Ash content %

=<0.15

=<0.15

=<0.15

=<0.35

TCVN2690:1995/ASTM

D482

Water content, by

volume

=<1%

=<1%

=<1%

=<1%

TCVN2692:1995/ASTM

D95

Purity, by weight =< =< 0.15% =< 0.15% =< 0.15% ASTM D 473 Flash point℃

66

66

66

66

TCVN 66O8: 20O0/

ASTM D382S/ASTM

HHV, kcal/kg >=

>= 10,000

>= 10,000

>=10,O00 ASTM D240/ ASTM

LHV, kj/kg

40,800(usual)

3.3.6 Characteristics of Fuel(heavy-oil)

3.3.6.1 Characteristics of heavy-oil

10 000 D480

3.3.6.2 The corresponding value of temp. of fuel burner entrance and viscosity of heavy oil (for

detail information refer to viscosity - temperature curve)

Item HFO No.1 HFO No.2A & 2B HFO No.3

viscosity of fuel required

in the entrance of burner

2.5 °E

2.5 °E

2.5°E

Required Matching temp. 95 ℃

110℃ 130℃

Required Matching density 0.917 0.934 0.922

3.3.6.3 J11 oil burner design parameter

HFO flow of

each burner

HFO

pressure of

Atomization

steam flow of

Steam

pressure of




each burner each burner each burner

l/h bar(g) kg/h bar(g)

Maximum

30% BMCR, running 12 burners

1935

20

110

5.25

Standard values

30% BMCR, running 16 burners

1450

14

115

5.25

Minimum 390 2 165 5.25

3.3.6.4 Requirement for oil and steam parameters in burners operation

Fuel oil parameter Steam parameter(dry steam as required) Viscosity at the burners

2.5°E (make the

corresponding

adjustment of the

temp, Estimated

at

Burner pressure

5.25 bar(g)

Burner pressure 2 ~ 20 bar (g) Temp. about 200℃ Flow

Maximum 30%

BMCR heat input,

namely 21280 kg/h.

The constant flow

in return line is

10% of

flow

Max continuous flow

2.6 t/h,

Peak flow is 3.9

t/h (atomization and

cleaning are

t d 3.4 Requirement for Quality of Boiler Steam

3.4.1 Requirement for Date of Quality of Boiler Steam in Normal Operation

Item Unit Normal range

1. Feed water

Conductivity (after cationic resin exchanger)

at 25°C Expected values :

µS/cm

(microSiemens/cm)

< 0. 3～0. 2

pH obtained by ammonia injection 9. 2～9. 4

Total hardness : i. e. not detectable by

l i t

Nil

Dissolved oxygen at degasser outlet mg/kg (O2) ≤ 0. 01

Hydroxide content at economizer inlet mg/kg (N2H4) > 0. 010～0. 020




Item Unit Normal range

Total iron (Fe), mg/kg < 0. 010

Total copper (Cu) mg/kg < 0. 003

Silica content, mg/kg (SiO2) < 0. 020

2, Boiler water

Conductivity (at 25℃) µS/cm < 20

pH (at 25℃ ) 9. 2～9. 5

Phosphate content mg/kg (PO43-) 2～3

Free caustic Nil Silica content, recommended

mg/kg (SiO2)

0. 010～0. 300

3.4.2 Alert date for abnormal quality of boiler steam

Steam sample Item Status Date

Condensate

pH value

dissolved oxygen

Cation conductivity

In the regular scope

More than or equal to

More than or equal to

9. 1 to 9. 5

20 ppb

0. 5 µS/cm

Feedwater at Degasser

outlet

dissolved oxygen

More than or equal t

10 ppb

Feedwater at

economizer inlet

pH value

Cation conductivity

Dissolved oxygen

Hydrazine


More than

Less than


9. 1 to 9. 5

0. 5 µS/cm

10 ppb

10 to 20 ppb

Boiler

Conductivity

pH value

Silicic acid

F

Na

More than

In the regular

scope

More than

More than

More than

50 µS/cm

9. 0 to 10. 0

100 ppb

1ppm

-

Saturated steam

Cation conductivity

Na

Silicic acid

More than or equato

More than

M th

0. 5 µS/cm

20 ppb

50 ppb

Superheated

steam

Cation conductivity

Na

More than or equato

M th

0. 5 µS/cm

20 ppb




Steam sample Item Status Date

Silicic acid More than 50 ppb




3.5 Boiler auxiliary equipment technical specifications

3.5.1 High-pressure bypass

1 Basic date Parameters

2 Use High-pressure bypass valve

3 Quantity Equipped with 2 units

4 Fluid characteristics

5 Type of fluid steam

6 Maximum control flow(max CV) 750 t/h (75%BMCR)

7 Min differential pressure at max CV 130 bar

8 Minimum inlet pressure at max CV 179. 3 bar

9 Max temp. at max CV 543 ℃

10 Minimum control flow(min. CV) 8 t/h

11 Max differential pressure at min CV 205 bar

12 Max inlet pressure at Min CV. 205 bar

13 Min temp. at Min CV. 420 ℃

14 Quick-opening set pressure 182. 8 bar

15 Slow –opening set pressure 179. 3 bar

16 Characteristics and specifications of

executive body

17

Differential pressure after the valve is shut

off

205 bar

18

Type of executive body (electric, pneumatic

and hydraulic)

hydraulic

19 Fault location indicator open

20 Solenoid operated control valve (SOV) or

it h b d f i k t t

yes

21 Manual control yes

22 Stroke Period (fast& control) 3& 20 sec(from 0％to100％)

23 Limit switch close

24 Pressure switch for air pressure difference no

25 Location transmitter yes

26 Gas source pressure reducer with

instrument

no

27 Characteristics




28 Design pressure 205 bar is effective

29 Design temp. 543+5 ℃

30 Tightness rank(selon / acc. to ANSI

B16-104)

rank V

3.5.2 Air preheater

Item

Unit

Design date

Form A. P( trisector, rotating the heating surface )

Type 2-29VI(T)-86”SMRC

Rotor diameter mm 10318

Rotor height mm 2185 Height of heating surface

mm

Hot section 1000, middle layer of hot section 880,cold

ti 305Quality set 2

Manufacturer SBWL

Motor Main Motor Auxiliary Motor

Type Y180M-4B3 Y160L-8B3(Double-axis)

Power kw 18. 5 7. 5

Voltage V 380 380

Rated Current A

Rotating speed r/min 1470 720

Reducer

Type SGW100D

Reducing rate of speed 128. 3

Axis rotating speed(main

t )

r/min

11. 46

Axis rotating speed(axial

t )

r/min

5. 61

Rated Torque output N. m 12300

Support bearing Thrust spherical roller bearing Type: 90394/750

Guild bearing Double-out centripetal roller bearing Type: 3153172

Oil circulation system

Guidance bearing dilute-Oil

station

Support bearing dilute-Oil

station

Oil station Type OCS-D2A OCS-D2A




Item

Unit

Design date

Type of Motor Y802-4B3

Motor power kw 0. 75(2 set)

Motor speed r/min 1390

Type of oil pump 3GR25×4 tri-screw pump

Flow m3/h 0. 8

Rated pressure MPa 1. 0

Working temp. of Cooler ℃ 60～70

Temp of cooling water ℃ ＜30

Consumption of cooling

t

m3/h 0. 8

Pressure of cooling water MPa 0. 2

Type of oil filter SPL25C-2 net

Type of oil cooler GLC1-0. 8 Tubular

3.5.3 Induced draft fan

Item Unit Design date Remarks

Form Axial adjustable static-blade

Type G158/273

Manufacturer Shanghai Blower works Ltd.

Quality set 2

Rotation direction Anti-clockwise At the direction of air flow

Motor Power Kw 1500

3.5.4 Forced draft fan

Item Unit Design date

Form Axial(hydraulic, adjustable moving-blade)

Type FAF20. 4-10-1

Manufacturer Shanghai Blower works Ltd.




Quality set 2

Air fan total pressure Pa 5267(T. B) 3660(BMCR)

Speed r/min 1470

Shaft output kw T. B:621,BMCR:405 T. B:650,BMCR:418

Efficiency ％

84.08(BMCR operating

condition:86. 50)

83.21(BMCR operating

condition:86. 72)

Range of moving-blade degrees 45

Rotation direction Anti-clockwise(at the direction of end of Motor shaft )

Rotation power kw 1250

Rotation speed r/min 1482

3.5.5 Primary air fan

Item Unit Design date

Form Single-suction centrifugal

Quality set 2

Type 1788AB/940

Manufacturer Shanghai Blower Works Ltd.

Speed r/min 1480

Outlet total pressure Pa TB:14850 Pa BMCR:11000 Pa

Inlet temperature ℃ TB:39 BMCR:24

Power kw 400

Direction Inlet:90o outlet:0o(from Motor side )

3.5.6 Mill fan

Type: M25452 Type: Centrifugal: Media of mill fan: air




Item

Unit

TB operating condition BMCR operating

condition

Standard Flow Nm3/h 151650 144430

Inlet Temp. ℃ 120 110

Inlet Gross Pressure Pa -8500 -8000

Outlet static Pressure Pa -700 -1200

Total Pressure of Air fan Pa 7800 6800

Selection point efficiency ％ 83. 1 76. 8

Compression correction

factor

0. 9735 0. 9767

Axial power kw 622. 5 543. 8

Rotation direction r/min 980

Rotation power kw 710

Rotation speed r/min 980

Motor voltage kv 6. 6

Manufacturer China ChengDu Electrical power machinery factory

3.5.7 Milling


Manufacturer Shanghai Heavy machinery Works Co. Ltd.

Mill cylinder type BBI4796

Mill cylinder effective

diameter

mm

4650

Mill cylinder effective length mm 9740

Milling method Ball mill with drying and purging by hot air





Main Motor

Manufacturer Shanghai Motor Works

Type YTM900-6

Power kW 3500

Voltage V 6600

Speed r/min 986

Electric heater

Single-phase voltage

V

230

Power 1200x2 W(used when

shut-down)

Main Motor lubrication dilute-oil station (XYZ-20)

Nominal pressure MPa 0. 5

Nominal flow L/min 20

Primary Lubrication

Volume

L

450

Lubrication Speciation 46 turbine oil L-TSA

Cooling water volume m3/h 2. 5

Power kW 1. 5

Voltage V 400

Speed r/min 1400

Main Reducer

Type ML2PSF150

Speed rate i 9. 275

Lubrication Type Reducer with compulsory lubricating of

independent dilute-oil station





Power kW 11

Voltage V 400

Primary Lubrication

Volume

L

1500

Lubrication Speciation ISO VG320

Cooling water volume m3/h 8

Low speed driving set [plant reducer(An auxiliary motor)]

Type NMCD560-125

Speed rate i 125

Motor Type YEJ280S-6(B35)

Motor Power kW 45

Motor Speed r/min 970

Motor Voltage V 400

Revolving speed of disk r/min 0. 105

Primary lubrication

volume

L

180

Lubrication Speciation Mid-extreme pressure industry gear oil N220(GB5903-86)

Main bearing HP and LP lubrication dilute-oil station

Type GDR-60/10/170

Lubrication Speciation L 2800

Cooling water volume ISO VG460

Cooling water volume m3/h 18

Electric heater Total 6 (400VAC/3kw x 6)





LP pump(1 set)

Nominal pressure L/min 170

Nominal flow MPa 1

LP Pump Motor(1 set)

Power Kw 7. 5

Voltage V 400

Speed r/min 1440

Injecting HP oil pump (1 set)

Nominal pressure L/min 4X15

Nominal flow MPa 20

Injecting HP oil pump motor(1 set)

Power Kw 30

Voltage V 400

Speed r/min 1470

Electric wire heater VAC/kW 230/

HP lubrication pump(1set)

Nominal Pressure L/min 2X5

Nominal Flow MPa 10

HP lubrication pump motor(1set)

Nominal Pressure Kw 3

Nominal Flow V 400

Speed r/min 1440





The girth gear grease circuit lubricating equipment

Type GSPZ-Z-8

Operation Pressure MPa 0. 4~0. 6

Max Pressure MPa 0. 8

Max volume of oil supply g/min 1500 0. 6MPa

Required gas supply

capacity

m3/min 0. 42

Working oil pressure MPa 20

Quantity 8

Lubrication Speciation NLG100-0

Gear sealing air equipment

Air fan type CQ3-J

Flow m3/h 800

Pressure pa 590

Power kw 0. 37

Voltage V 400

Speed r/min 2900

Spring coupling equipment

Primary grease volume kg about 4

Grease speciation NLGI 02 Lithium Grease

lubricants

Gear coupling equipment

Primary grease volume kg About 13





Grease speciation E. P. Lithium Grease lubricants

Small gear equipment rolling bearing

Grease speciation SKF ALFALUB LGEP 2

3.5.8 Cold feeder

Item Specification Manufacturer

Main body

MSD100

China's Hubei YiDu Electrical and Machinery

Engineering Co., Ltd.

Motor YVP160L-6 China Xi An Motor Works

Reducer ZSY250-80 China's JiangYin, JiangSu gear box Works

Output 30～110 Tons／hour

3.5.9 Pulverized Coal feeder


Manufacturer China ShenYang Power Plant Engineering Ltd.

Type SGF－13

Output t/h 3～13

3.5.10 Pulverized Coal Feeder


Manufacturer China ShenYang Power Machinery Works

Type LSG－500

Transmission distance m 32. 2

Motor Power KW 7. 5 2




3.5.11 classifier


Manufacturer Chian Wuxi Liangxing power equipment Ltd.

Speciation Φ6800mm

3.5.12 Thin pulverized coal separator


Manufacturer China WuXi Joint Venture Power Equipment Co., Ltd.

Speciation Φ3500mm

3.5.13 Vent fan


Manufacturer China's Shenyang Blower Factory

Type SFY15F-C5A

Form Single inhalation double support centrifugal

Direction of air intake 90° left rotation(right rotation)

Direction of air outtake 45° left rotation(right rotation )

Impeller diameter mm 1500 Blade outlet

Rotor critical rotation speed r/min 1930

Inlet flow volume m3/s 28. 36

Air fan total pressure KPa 5. 7

Inlet temperature ℃ 120

Air fantotal pressure effciency % 84

Air fan axial power kW 200

Motor effciency kW 250




Motor voltage kv 6. 6

3.5.14 Boiler water circulation pump


Form LP head with no seal

Type LUVc250×2-410/1

Manufacturer England Heyward Tyler

company

HAYWARD TYLER

Medium water Single inhalation

double support centrifugal

Quantity set 3 2 operation meet BMCR

Design pressure bar 210

Hydraulic test pressure bar 315

Absorbed pressure bar 198

Medium density S·g 0. 554

Design temperature ℃ 369

Max differential pressure of

pump shell and boiler water

℃

lower than 56 Higher than 56℃ trip

Pump flow m3/h 2182 Single

Efficiency ％ 83 Cold/hot

Absorbed efficiency kw 222. 7 Hot:130. 0

Pump inlet and outlet

differential pressure

MPa

about 0. 3(31. 1mH2O )

Lower than 0. 11 alarm Lower than 0. 055 trip

Motor

Form Three-phase squirrel-cage




induction

Type LUV55/4FQ20-605

Rated power kw 200

Rated voltage KV 6

Rated speed Rotation speed r/min 1450

Rated current A 27. 5

Start-up current A 135

Motor efficiency ％ 88. 0/87. 0 cold/hot

Power factor 0. 805/0. 72 cold/hot

Input power kw 252. 8/140. 5 cold/hot

Total efficiency of pump ％ 73/72. 2 cold/hot

Water cooler of HP filling water and cleaning water

HP side design pressure MPa 21

HP side hydraulic test

pressure

MPa

31. 5

LP side design pressure MPa 1

LP side hydraulic test

pressure

MPa

1. 5


Motor heat exchanger

HP side design pressure MPa 22

LP side design pressure MPa 3

LP side required pressure MPa 0. 65

HP side design temperature ℃ 343




LP side inlet temperature ℃ 38 max

LP side outlet temperature ℃ 44 max

HP side motor circulation

water volume

m3/h 11

HP side motor circulation

water temp.

℃

32～49 normal operation

LP side required flow m3/h 8. 5 Lower than 6. 5alarm

Heat exchanging efficiency kJ/s 34. 2 Cold,2 pump operation

Required flow forLP

cooling water hot panel

m3/h 2 Lower than 1. 5alarm

hot panel outlet

allowable highest temperature

℃

50

LP cooling water hot

panel required pressure

MPa

0. 2

At flow 2 m3/h, hot

panel pressure drop

KPa

0. 05～0. 08

3.5.15 Flame scanner cooling air fan


Manufacturer SBWL

Type VC 710 N/2

Air flow m3/h 1153

Total pressure Pa 9480

3.5.16 Intermittent and continuous blowdown flash tank


Manufacturer China Jinan pressure vessel plant




Continuous blowdown flash tank

Form Vertical

Type LP-3. 5

Volume m3 3. 5

Design pressure MPa 1. 5


Intermittent blowdown flash tank

Form Horizontal

Type DP-20

Volume m3 20



3.5.17 Steam air preheater


Manufacturer China Hankou power equipment plant

Primary air A. P

Type NFZ3. 2-1-2. 645FBZ

Volume m3 185



Secondary air A. P

Type NFZ3. 2-1-2. 690FBZ

Volume m3 607. 5






Steam air preheater

drain box

Type NSL-16-0. 5

Volume m3 0. 5

4 Boiler and interlock protection value auxiliary equipment.

4.1 Boiler protecting Limit Value

Name Units LL L N H HH Remarks

Drum water

level

mm

-425

-240

100％Load:0

50％Load -115

+100

+200

Drum water level

under the center

line of drum －

175mm;

L, H: alarm;

HH/LL B il MFT

Furnace

pressure

Pa

-2500

-2000

-100

+1000

+4000

L, H: alarm, LL/HH: Boiler MFT

Burning oil

pressure

Mpa

0. 5

1

2. 5

N:HPO isolating valve

allowable L: alarm

LL: Burning oil trip

H:HPO pressure

high alarm

Burning oil

pressure

Mpa

1. 85

1. 9

N:HPO leaking

test pressure proper





H: HPO leaking

test pressure low

Burning oil

temperature

℃

90

95

100

135

N:HPO temperature

allowable

L:HPO low

temperature alarm

LL/H:HPO trip

Atomization

steam

pressure

Mpa

0. 4

0. 5

0. 9

L: low pressure alarm LL: low pressure

Burning oil trip H: high pressure

alarm

Atomization

steam

temperature

℃

180

230

L: low temperature

alarm

H: high

temperature alarm

4.2 Boiler auxiliary interlock protection value auxiliary equipment.


1. Air

preheater

Bearing

temperature

℃

<70

70

85

N: open allowable; H: alarm profit Air

Preheater open;

HH: Air Preheater trip

1）

Rotation

speed

r/min

0. 5

0. 8

1

L: alarm, delay 10Sjum

to Motor, then after 3 s

open stand-by M t




LL: air preheater trip

2） Inlet

flue gas

temperature

℃

150

419

L: after lower than L

allow stop Air

Preheater

3） Temp.

of primary

and

d i

℃

378

478

H: fire alarm

4） Soot

blowing

Steam temp.

℃

130

If L: higher than L allow

soot blowing

5）

Soot

blowing

steam

Mpa

1. 04

1. 2

L: soot blower

allow soot blowing

Working pressure

6） 2．ID Fan

Lubrication

flow

L/min

3

4

>3 ID Fan open

allow;<3alarm

Lubrication

pressure

Mpa

0. 12

0. 4～

0. 6

L: alarm; LL:

alarm, delay 30S trip

Hydraulic oil

pressure

Mpa

0. 86

2. 5

LL: stand-by pump

automatic;

L:ID Fan open allow

Oil filter

differential

pressure

Mpa

0. 35

H: alarm

Oil position of

oil bank

mm

150

blanking ID Fan open, alarm

Bearing ℃ 60～70 90 110 H: alarm;




temperature HH: ID Fan trip

Temp. of Oil

in Oil Bank

℃

30

30-40

40

L: open heater H: close heater

Oil cooler

outlet

temperature

℃

45

＞45℃,alarm

Surge

Kpa

+100

on site

delay 15S ID

Fan trips

Motor

bearing

temperature

℃

85

95

H: alarm, prohibit

open; HH: trip

Stator coil

temperature

℃

90

130

135

H: alarm, prohibit

open; HH : trip

3．FD Fan

Bearing

temperature

℃

80

90

Motor

bearing

temperature

℃

90

100

Motor coil

temperature

℃

130

140

Vibration mm/s 8 11

Lubrication

pressure

Mpa

0. 35

L: alarm; LL: alarm, trip

FD fan

lubrication

flow

L/MIN

3

>3FD Fan open

allow;<3alarm




FD fan

hydraulic oil

pressure

Mpa

0. 86

2. 5

L: stand-by pump open

automatic

H:FD Fan open allow

FD fan

differential

pressure

Mpa

0. 35

H: alarm

FD fan oil

location of oil

tank

mm

150

L: alarm

FD fan temp.

of oil in oil

tank

℃

30

30-40

40

L: open electric heater H: close electric heater

FD Fan oil

cooler outlet

temperature

℃

45

＞45℃alarm

FD fan surge

KPa

On site

delay 15S and FD Fan

trips

4．Primary air

fan

Bearing

temperature

℃

80

90

Motor bearing

temperature

℃

90

100

Motor coil

temperature

℃

130

140

Vibration mm/s 8 11

Outlet air

pressure

Pa

2400

3000

L: alarm, LL:

Pulverized coal




trip, N: adjustment

5．Pulverized

coal exhauster

Bearing

temperature

℃

80

90

Motor bearing

temperature

℃

90

100

Motor Coil

temperature

℃

130

140

Vibration mm/s 8 11

6．Vent air fan

Vent fan bearing

temperature

℃

80

90

Vent fan motor

bearing

temperature

℃

90

100

Vent fan motor

Coil

temperature

℃

130

140

Vibration mm/s 8 11

Vent

temperature

℃

90

110

120

130

L, H: alarm; HH: Stop Vent fan

High temp. for

produce

pulverized

℃

300

700

800

L, H: alarm

Bag type filter ℃ 150




temperature

7．Mill

Mill

Lubrication

pump outlet

main pipe

pressure

Mpa

1. 035

H: Open safety valve

at lube oil pump outlet

HP oil

pressure

Mpa

0. 02

Jacking oil

pressure

Mpa

1. 5

1. 8～23 Mill open

allowable ; HH: Open

Safety valve at jacking

oil pump outlet

Bearing

rotation oil

pressure

Mpa

3

Bearing

temperature

℃

45

<85

65

70

N: Mill open allowable;

H: alarm

HH: Mill trips

Mill small

gear

Bearing

temperature

℃

<77

77

88

N: Mill open allowable H: alarm

HH: Mill trips

Temperature

of reduction

gearbox

℃

<85

85

90

N: Mill open allowable

H: alarm HH: Mill trip

Motor bearing

temperature

℃

<80

80

90

H: alarm HH: Mill trips




Motor coil

temperature

℃

<120

130

140

H: alarm HH: Mill trips

Lubrication

temp

℃

24

27

32

46

49

＞ LL: allow

opening Lubrication

pump; L: put

electric heater; N:

stop electric heater; H:

h t b t l lLubrication

filter

differential

pressure

MPa

0. 15

0. 25

L: alarm;

Lubrication

flow

L/min

30

L: alarm

Reducer oil

supply flow

L/min

60

Cooling water

flow

m3/h

15 ＞ L: Mill open

allowable

Temperature

of mill

inlet primary

air

250

＜ H: Mill open

allowable

Mill inlet

Primary air

pressure

Kpa

3

11

＞ L: Mill open

allowable

＞H: Mill trips

Classifier

outlet primary

air temp.

℃

100

150

175

L: Mill open allowable;

H: delay 3min Mill trips

Differential

pressure of

non-drive Inlet

and classifier

Kpa

3. 5

4. 5

＜ N: open coal

feeder allowable;

≥H: alarm, delay

15M and Mill

t i Date: 2008-09-15 No.: QN1-SEC-G-04-TP-003 Page 41 Rev. : A



outlet primary

air

Differential

pressure of

drive Inlet and

classifier

outlet primary

air

Kpa

3. 5

4. 5

＜N: open coal

feeder allow;≥H:

alarm, delay

15M Mill trips

Mill

Lubrication

station strainer

differential

pressure

Kpa

207

242

＞H: Require changing

the strainer;

＞HH: go bypass

8．Boiler water

circulation

pump

pump inlet

outlet

differential

pressure

Mpa

0. 10

0. 14

L: Low differential

pressure alarm

LL: Low differential

pressure trip

Motor room

temperature

℃

55

60

H: high temperature

alarm

HH: high temperature

trip

9．Air

compressor

Compressed

air main pipe

pressure

Mpa

0. 4

0. 55

0. 75

L/LL: alarm, shunt

open stand-by Air

compressor

Air Mpa 0. 7 0. 8 L: load, unload




compressor

vent pressure

Air

compressor

cooling water

outlet

temperature

℃

50

10．Soot

blower

Soot blowing

steam supply

pressure

Mpa

3. 0

3. 5

LL: alarm

Drain

temperature

℃

280

H: close drain valve

and allow soot blowing

Steam air

preheater

Water level of

drain tank

mm

200

300

550

800

900




5 Start-up

5.1 Basic Regular

5.1.1 Before the start-up of the new erected or overhauled boiler, the trial operation, test and

equipment acceptance of main equipment and auxiliary equipment should be finished. Before

start-up of the boiler having minor repairs, the trial operation and test and equipment

acceptance of the repaired equipment should be finished.

5.1.2 After major or minor repairs, the shift supervisor should have the final report about

improved items of equipment and instruments after finishing system change.

5.1.3 Choose the right method of start-up

5.1.4 If the following arbitrary conditions occur, the start-up boiler should be prohibited:

5.1.4.1 If the repair work of the system or equipment affecting the boiler start-up is not finished or

work sheet is not canceled, inspection test and trial operation is not acceptable.

5.1.4.2 Interlock, protection and trip test are not performed.

5.1.4.3 DCS system is not in service affecting the operation and monitoring of the units.

5.1.4.4 Thermal control main instrument. For e.g., main steam temperature, main steam pressure,

reheat steam temperature, reheat steam pressure, drum water level, furnace pressure,

feed water flow and steam flow can’t be put in service.

5.1.4.5 Quality of boiler water can’t reach the requirement.

5.1.4.6 FFCS can’t be put in service.

5.1.4.7 Thermal control signal system can’t be put in service.

5.1.4.8 The safety valve system for main boiler auxiliary system (e.g. Safety valve, ERV valve,

drum emergency drain valve, burning oil Electromagnetic valve) are not in service.

5.2 Repair test and acceptance inspection

5.2.1 Requirement of acceptance inspection refers to acceptance inspection procedures in

instructions of boiler professional overhaul

5.2.2 Acceptance inspection after repair should be executed acc. to scattered trial operation

acceptance inspection and system trial operation acceptance inspection and whole start-up

acceptance inspection.

5.2.3 All acceptance inspections of thermal control interlock test are confirmed by static test

method.




5.2.4 All auxiliary scattered trial operation acceptance inspection is through acceptance

inspection of motor empty operation and the method with auxiliary equipment operation.

5.2.5 Classification of repair test

5.2.5.1 First type of test:

A. Hydraulic test of boiler body.

B. Furnace cold air dynamic field test.

C. Procedure control test for soot blower and blowdown.

D. FSSS, CCS cold position simulation test.

E. Safety valve setting test.

F. Each rotation machine Single logic test.

G. Air leaking test of boiler body.

5.2.5.2 Second type of test:

A. Interlock test of Boiler rotation machine (including milling system). B.

Accidents button Test of Boiler rotation machine.

C. Single protection trip test of Boiler rotation machine.

5.2.5.3 Third type of test:

A. Main valve, duct damper single test.

B. Each intermittent work, intermittent test.

5.2.5.4 Test requirement:

A. All tests should be done after overhaul.

B. Before starting the units, minor repair, sudden inspection and the second and third

type of test should be done. If necessary, the first type of test is also required.

C. Make the associated test when the equipment is abnormal.

D. HP motor is usually done the static test

E. The responsible department should write a detailed testing procedure. They shall

report it to higher authorities for approval and the test result with

signature the




relevant departments authorized is also required.

F. Make the detailed record for the test. Any issues should be reported to the relevant

depart and dealt with till acceptable.

G. Each intermittent work and intermittent switching test is required acc. to the relevant

requirement.

5.2.6 Boiler Hydraulic test

5.2.6.1 The over-pressure test should be performed if any of the following situation

occurs(Working pressure test first):

1） After major repairs or replacement of the heating surface (replacement of water

wall tubes is more than 50%, replacement of any components of superheater,

reheater,

economizer and major repairs of drum).

2） Resume operation after shut-down for more than 1 year.

3） Boiler pressure is seriously more than 1.25 times of working pressure.

4） Large deformation of heating surface occurs after serious shortage of water.

5） Acc. to the operation status, the reliability of safety equipment is suspected.

6） After major and minor repair or repair of local heating surface of boiler,

working pressure test should be done.

5.2.6.2 Boiler Hydraulic test pressure value is as following:

Primary system Secondary system

Working pressure(MPa) 20. 5 4. 5

Overpressure test(MPa) 30. 75(1. 5 times) 6. 75(1. 5 times)

5.2.6.3 Boiler Hydraulic test scope :

1） Primary system includes all the pipes, heating surface and header from non-return flap at

feedwater pump outlet to HT superheater outlet (i.e. including feedwater pipe, economizer,

drum, water wall, LT superheater, HT superheater, connecting pipes and header).

2） Secondary system includes all the pipes, heating surface and header from reheater inlet

to HT reheater outlet (i.e. including LT reheater, HT reheater connecting

pipes and header).






3） At working pressure, the following valve should be check secondary damper firstly and

then primary damper(Acc. to the test procedure):

A. Lower furnace drum drain valve.

B. Drum Air damper.

C. Economizer outlet pipe Air damper

D. Superheater Air damper.

E. Reheater Air damper.

F. Superheater drain valve.

G. Reheater drain valve.

H. Thermal control instrument pipe valve (If there is not any secondary damper only do

pressure test for primary damper).

4） At working pressure, pressure test will be only done for primary damper of the

following pipe valves:

A. Soot blowing steam primary damper.

B. Primary attemperator drain primary damper.

C. Secondary attemperator drain primary damper.

D. Reheater attemperating water primary damper.

E. Chemical sample primary damper.

F. Intermittent blowdown primary damper.

G. Blowdown primary damper.

5） For blowdown system at the furnace bottom, close motorized valve

firstly. Open completely the former manual valve to do pressure test. If the test is

acceptable, close manual valve to do pressure test.

6） Working pressure test with remote and local water level instruments, i.e. close the

remote water level instrument drain valve and local water level instrument

drain valve and completely open other damper, test water level instrument drain

valve; then close water level instrument and try water side and steam side primary

damper.




7） At working pressure, perform pressure test with drum safety valve, check seal conditions

but the valve stem should be jammed by the feed screw to prevent trip. Other superheater

and reheater safety valve should be jammed and isolated.

8） Open economizer re-circulation damper when it is fed water. if it is finished

close the damper.

9） Perform the overpressure test, withdraw remote and local water level

instrument and isolate or jam each safety valve. Boiler water circulation

pump motor and Boiler is thoroughly isolated. Boiler water circulation pump

plugging plate for overpressure test should be installed.

5.2.6.4 Conditions for Boiler Hydraulic test :

1） All steam pipe valve in pressure test, after heating surface repair work,

should be acceptable; Motorized valve, pneumatic valve, control valve

should be finished adjustment. And acceptance inspection is acceptable.

2） After check, installation and reset of steam system pressure instrument

should be finished. Primary system pressure test is confirmed by drum local pressure

instrument on roof. Secondary system pressure test is confirmed reheater inlet local

pressure. Pressure instrument accuracy is 0.5. The span should meet the test

requirements(span shall be 1.5

to 2.0 times of overpressure test pressure).

3） Each system Suspenders, springs and hangers have been adjusted and forced smoothly.

4） Each valve, Setscrew, Suspenders (Hanger) shouldn’t be fixed too tightly before hydraulic

test.

5） Expansion indicator correction is finished, and direction is correct.

6） Boiler platform, stairs path is Unobstructed, remove all impeding scaffolding

7） Drum wall temperature measurement points is corrected and can be put in service.

8） The scaffoldings of each checking parts are safe and firm with adequate light.

9） Feedwater pump trial operation is acceptable.

10） Pressure test provisional pipes are installed and checked acceptable.

11） HP bypass “quick open ” condition is compulsive.

12） Producing water by Chemical water system is in service. Chemical feed system and






chemical is prepared. Water quality and chemical is checked acceptable. Water used by

primary system is about 550t (about 2 times of water Volume ).

Water used by secondary system water is about 180t adopting

dematerialized water. Test water is dematerialized water with 200 ppm

ammonia+ hydrazine treatment and PH value is higher than 10. 5.

13） Emergency pressure drop method must be prepared. Intermittent blowdown valve

and motorized drain valve at lower furnace drum are well stand-by

and pipes are unobstructed to do quick pressure drop if overpressure.

14） Set up local pressure instrument of drum and reheater and make control room with well

communication.

15） When hydraulic test, circumstance temperature is usually higher than

5℃,otherwise make the anti-freeze measures. Water temp. from 30 to 70℃ is suitable

(not lower than

20℃).

16） At working pressure hydraulic test shall be chaired by repair

(installation) tech. responsible staff. Overpressure test shall be chaired Chief

Engineer and designated person in charge.

17） All test staff should follow a clear division of labor, subject to a unified command and

insist on jobs.

5.2.6.5 Introduction of hydraulic test method: Open motorized feedwater pump and fill the water

through economizer from main feedwater system. One side of superheater secondary

attemperator water or main feedwater bypass pipes raise pressure, but these two

methods can’t be performed at the same time. Only one can be selected. Reheating

system feeds water to Reheating system through attemperating water pipes. Close main

feedwater pipes valve and then do pressure test.

Test should be performed in order of high to low, i.e. Hydraulic test of steam system,

then hydraulic test of reheater system.

If all tests are finished, do pressure drop and drain. Do pressure test

for some secondary damper and primary damper.

5.2.6.6 Hydraulic test steps

1） Open all air damper of Drum, Superheater and reheater system

2） Close all drain valve of Superheater and reheater system.






3） Besides drain primary damper of intermittent blowdown, continuous blowdown, cold

reheater, close all drain primary damper and secondary damper.

4） Close boiler main steam valve and main steam bypass valve, close primary drain valve,

secondary drain valve in front of main steam damper.

5） Before hydraulic test, 3 boiler water circulation pumps should be fed water to

exhaust steam acc. to the manual, (Notice: Hydrazine can only be fed to

deaerator, not to condenser). After filling water and exhausting air, open outlet non-

return flap of 3 boiler water circulation pump.

6） Acc. to normal filling procedure fill the boiler to the visible drum water level. Stop

filling through feedwater pipe and change to filing through superheater water spray

secondary attemperator till air dampers of drum and superheater is continuously

overflowing the water. Close air dampers of superheater and drum and stop filling.

7） Forbid filling the boiler through feedwater control system and superheater water spray

attemperating at the same time.

8） Check HP bypass damper at “closed ” condition and quick open condition

is been compulsory.

9） Check reheater system pressure zero.

10） Completely open motorized pump recirculation damper and valve of

some side of secondary superheater attemperator water and motorized isolation

damper. Micro-open motorized control valve. Make use of the open position of the

motorized control valve and feedwater pump rotation speed to control pressure rising

speed ≯0. 3Mpa/min.

11） Before filling, after filling water is full and when working pressure is reached, the record

of indicators of expansion system shall be checked.

12） If whole pressure rising reaches 1～2Mpa, 10M Pa and 75％ of working

pressure, suspend pressure rising and do primary check for Primary

system. if it is normal, continue raising pressure. if working pressure is

approached, decrease pressure rising s peed ≯0. 2Mpa/min to prevent overpressure.

13） If primary system pressure reaches 20. 5Mpa, stop pressure rising,

monitor local pressure instrument of drum, record the status of

5min pressure drop and comprehensively check each heating surface and pipe

valves.






14） Acc. to the scope of pressure test, switch the primary valve and secondary valve of

primary system. Raise pressure again to 20. 5 Mpa, record the status of 5 min pressure

drop and check each first valve etc.

15） If overpressure test is required, after above check result is normal, confirm boiler

water circulation pump motor and boiler water are isolated and boiler water circulation

pump plugging plate for overpressure test is installed. Drum water level instrument trips.

After the staffs withdraw the scene, with pressure rising speed ≯ 0.

1Mpa/min raise the pressure to 30. 75Mpa .Keep 10～20min and then open final

superheater air valve at roof or cold superheater drain valve to do the pressure drop.

Pay attention to pressure drop speed ≯0. 1Mpa/min. After pressure is dropped to 20.

5Mpa, close pressure drop

air valve or drain valve, record the status of 20 min pressure drop, and comprehensively

check.

16） If pressure test is acceptable or check abnormal, open superheater drain valve, drop

the pressure to zero and pay attention to controlling pressure drop speed≯0.

3～0.

5Mpa/min.

17） When hydraulic test of primary system is finished, do hydraulic test of reheater system.

18） Use reheater attemperating water pipe to fill the reheater, after water

overflows at reheater outlet air damper, close all reheater system air dampers, open

the first reheater exhaust steam valve and stop filling water.

19） Control feedwater pump rotation speed. Through reheater attemperating water

control valve with ≯ 0.3Mpa/min pressure rising speed and raise the

pressure to 1

MPa. Comprehensively check reheater system.

20） If the check result is normal, raise pressure to 4. 5Mpa, stop pressure rising,

isolate reheating system, monitor local provisional pressure instrument 5min, record the

status

of pressure drop and comprehensively check reheating system.

21） Acc. to scope of pressure test, switch the primary valve or secondary valve of

primary system, do pressure rising again to 4. 5 Mpa and record the status of 5 min

pressure drop.

22） If the overpressure test is required, after above check result is normal and the staffs



withdraw the scene. With pressure rising speed ≯0. 1Mpa/min raise the pressure to 6,

75Mpa. Isolate reheating system, keep 10～20min and observe changes in pressure.




23） Micro-open final reheater air valve at the roof to drop pressure, monitor provisional

pressure instrument and pay attention to pressure drop speed ≯0.1Mpa/min

when pressure reaches working pressure in the overpressure test. When pressure drop

to 4.

5Mpa, close pressure drop air valve, record the status of 5 min pressure

drop and comprehensively check

24） When reheating system pressure test is acceptable, open final reheater air valve at roof

or reheater drain valve to drop the pressure to zero, monitor provisional

pressure instrument and pay attention to pressure Drop speed ≯0. 3~0. 5Mpa/min.

25） When pressure test of reheating system is acceptable, drop pressure to zero and

open superheater and reheater drain valve to drain. For e.g., if Boiler needs draining,

open lower furnace drum blowdown valve to comprehensively drain for drum and water

wall.

5.2.6.7 The key position for hydraulic test check:

1） Whether the valve of each system after repair is leaking.

2） Whether joint of safety valve is leaking.

3） Whether each heating surface, especially the position having repair work

and the position requiring strict check is leaking and deformation.

4） Whether each expansion indicator, pipes hanger has abnormal expansion.

5.2.6.8 Hydraulic test acceptable standard(Hydraulic test meet the following requirements, i.e.

acceptable ):

1） There are no leaking traces of water on pressure parts, metal wall and welding seam.

2） At primary system working pressure, when stop raising pressure., pressure drop in 5min

is <0. 5Mpa. At secondary system working pressure, when stop raising

pressure, pressure drop in 5min is ≯0. 25MPa.

3） No obvious deformation of pressure parts.

5.2.6.9 Boiler hydraulic test attentions :

1） When boiler is fully filled water, before pressure rising, jam drum and superheater safety

valve; When doing hydraulic test for secondary system, jam reheater safety valve; when

do overpressure test, jam each safety valve.

2） If reheating system has provisional pipes, the pipes should be purged before installation,






each welding seam should be check acceptable and welded by acceptable welder.

3） Feedwater pump reach the top pressure, completely open recirculation valve and strictly

monitor operation conditions to ensure feedwater pump operation safe.

4） Each drain valve of main steam valve outlet drain, cold reheater and hot reheater should

be opened. Immediately check whether there is any water is drained to prevent cylinder

from water.

5） Each drain valve at main feed water equipment side should be checked whether the valve

is strict leaking and pay attention to the water entering into HP heater at pressure rising.

6） When raising pressure, monitor attemperating water flow. If flow is big and pressure rise

is slow, system leaking may be serious. Check the cause intermediately.

7） Boiler filling shall be performed acc. to filling requirement.

8） Monitor drum wall temp.>20℃ in the test and differential temp.≤50℃. When

drum is checked, heating surface wall temp. should be ≤49℃.

9） After test, open drain valve and air damper firstly to drain. If drain is finished,

dismantle plugging plate valve. Because there is no drain pipe in front of the plugging

plate valve, most of the water can’t be drained. When dismantle plugging plate valve,

firstly ease the plugging plate, let the water leak slowly form plugging plate valve to

prevent steam pipes from full water and then open drain valve of steam pipes to prevent

cylinder from water.

10） When do the hydraulic test, specified staff should monitor pressure instrument.

Drum local and remote pressure instrument should be often checked.

Emergency pressure drop pipes valves shall be unobstructed. The valves

should be operated by specified person to prevent overpressure.

11） When do the pressure test, stop all welding work on boiler body, prohibit opening valve

and striking on the pressure parts arbitrarily.

12） Scaffoldings of each checking parts are complete. The path is unobstructed and full of

light.

13） Specified person should be responsible for pressure rising to

strictly prevent overpressure acc. to local pressure. When pressure reach10% of test

pressure, correct local pressure instrument and control pressure instrument. When the

differential pressure

is large, contact with the relevant person to deal with it.






14） When do hydraulic test, the relevant person should follow a clear division of labor,

subject to a unified command and set a clear and reliable communications.

15） Only test staff can be permitted in to the scene.

5.2.7 Boiler safety valve check

5.2.7.1 Conditions and requirement for safety valve check.

1） After major repair of boiler and repair or replacement of the valve, the hot check must be

performed for safety valve to maintain the reliability.

2） Safety valve set value is performed as following:

Setting pressure

Design

temp

No.

Location

Type of valve

Specification

(inch)

Opening

MPa

reseating

MPa

Blow

down

Differential

pressure%

Discharging

capacity

t/h

℃

1 DRUM HE-96W 3 M2 6 20. 50 19. 89 3 291. 697 369

2 DRUM HE-96W 3 M2 6 20. 60 19. 78 4 293. 924 369

3 DRUM HE-96W 3 M2 6 20. 70 19. 67 5 296. 175 369

4 Reheater

outlet

HCI-98W

3 L2 6

18. 70

18. 14

3

153. 860

557

5

Reheater

outlet

HCI-46W

6 RR10

4. 50

4. 37

3

253. 574

313

6

Reheater

outlet

HCI-46W

6 RR10

4. 60

4. 46

3

259. 366

313

7

Reheater

outlet

HCI-48W

6 RR10

4. 10

3. 98

3

187. 347

554

8

Reheater

outlet

HCI-48W

6 RR10

4. 20

4. 07

3

191. 810

554

9

Superheate

r

outlet(ERV)

E0L121N7BWR

A5P1

2..5″×4″

18. 50

18. 13

2

166

557

3） Before igniting the boiler, the safety measures to prevent the turbine from the steam

must be done.

4） The leader from tech. dept. and safety dept. should be on site when checking the valve.




It is conducted by chief engineer, chaired by repair staff in charge and operators

participate in it. When test, the relevant person should follow a clear division of labor,

subject to a unified command to prevent overpressure.

5） Set a convenient, clear, reliable communication.

6） Strictly close boiler main steam valve, turbine main steam valve, IP main steam

valve and HP drain valve non-return flap etc. Open turbine main steam

drain valve, cold reheater drain valve and hot reheater steam drain valve.

7） Turbine turning shall be put in service before the unit gets any load.

8） Drum water level high signal is compulsory (Drum water level protection releases ).

9） HP bypass quick open condition is compulsory.

10） When check safety valve, pressure indicator of local pressure instrument and before

operating control panel of drum, superheater, reheater and turbine main reheater steam

must be corrected. The local data and the date on the control panel shall

be same. When there are errors between the data on pressure

instrument of local pressure instrument and control room CRT, local pressure

instrument should be followed. In the process of pressure rise and checking,

paid attention to correcting local and before operating the panel. Specified

person monitor the pressure and contact relevant staff.

11） Checking safety valve shall be performed when boiler is started only or the load of

unit is only 10%—20% ECR load.

12） Pressure rise of boiler shall be performed acc. to pressure rising curve. In the process

of pressure rise, strictly monitor tube temperature of heating surface in the allowable

value.

13） When check, monitoring and adjustment for the burning and water level

shall be strengthened to prevent full water, inadequate water and overpressure.

14） When safety valve is being checked, if the valve is opened, the staff shouldn’t approach

safety valve.

15） When accidents occur, stop checking and acc. to relevant accidents

treatment requirement perform treatment.

16） When check, strengthen the contact and strictly finish each work acc. to each division of

labor.






17） Check for safety valve is performed in the order of high action pressure to low.

Unchecked safety valve should be isolated.

18） When check safety valve, firstly check by the opening aid checking equipment. If it is

acceptable, actual opening check can be performed.

19） When check ERV valve, actual opening check after control return circuit

check is acceptable.

5.2.7.2 Drum and superheater safety valve check :

1） Trip water level protection.

2） Open HP bypass and put HP bypass in automatic service to ensure cooling the reheater

system. Open steam exhaust valve at reheater outlet.

3） Control boiler combustion rate, put 4 to 8 oil burners in service.

4） When main steam pressure reach 10bar,stop pressure rising, inform the repair staff of

hot fixing screws and comprehensively checking welding, valve, man hole and hot

expansion conditions of pressure parts. If check is finished, after repair staff

Informing of raising pressure, continue raising pressure.

5） When turbine condenser vacuum reach 300mbar, put LP bypass in service.

6） When pressure reaches 75 ～ 85 ％ of safety valve test pressure

and stability is maintained, repair staff check safety valve by hydraulic check

implement, record opening pressure and reseating pressure till it is checked acceptable.

7） If informed of continuing pressure rise, put bypass control valve in “manual“ control.

Manual control the position of indicator of HP bypass (mustn’t

close),slowly raise pressure to safety valve design opening value and then

keep it. Repair person shall adjust it.

8） After opening safety valve, major open HP bypass manually and let

safety valve reseating.

9） Record opening pressure and reseating pressure of safety valve.

10） If the action of safety valve is incorrect and adjustment is required, repair

staff shall requires pressure drop or drop pressure to 75～85%of rated pressure. And

then adjust the safety valve acc. to manufacturer requirement.






11） If adjustment is required for more than 3 times, the adjustment should be performed

after safety valve is cooled. In cooling period, the staff can check other safety valves, but

need locking the cooled safety valve.

12） When check safety valve, if safety valve has no action, keep pressure stable.

13） Raise pressure to safety valve opening pressure, pop safety valve. When safety valve

has action, record the data of opening and reseating pressure.

14） Using the same method to check each safety valve of drum and each safety valve, ERV

valve of superheater in the order of high open pressure into low.

15） If safety valve check is finished, all safety valve lock shall be dismantled and the safety

valve should be in service.

5.2.7.3 Reheater safety valve check:

1） If safety valve of drum and superheater check is finished, resume water level, control

the combustion and control boiler pressure drop speed. If pressure drops to 6～8MPa,

use HP, LP bypass or units load to control the setting pressure of safety

valves of reheating steam to reheater inlet. Stabilize the combustion and maintain stable

pressure.

Repair staff should check reheater safety valve.

2） Adjust opening and reseating pressure of safety valve to 75～85%of test pressure.

Other operation and record refer to drum and superheater safety valve.

3） Using same method, check each reheater inlet safety valve and outlet safety valve in

the order of high opening pressure to low.

4） If safety valve check is finished, all safety valve lock shall be dismantled, put safety

valve in service.

5.2.7.4 If safety valve check is finished, acc. to the shift supervisor’s order shut-down the boiler

or raise temperature and pressure to start up the boiler.

5.2.7.5 If safety valve check is finished, inform thermal control staff of releasing signal of

compulsory.

5.2.7.6 Attention for safety valve check:

1） When check safety valve, HP bypass can’t be closed completely to prevent

reheater “burning”. Also LP bypass can’t be closed completely; otherwise reheater

outlet steam exhaust valve should be opened.






2） In order to decrease safety valve center erosion, after the action of safety valve,

Pressure Drop should be performed to let safety valve reseating.

3） When check safety valve, fluctuation of drum water level is large.

Prevent full or inadequate water accidents lead by false water level.

4） When safety valve takes action, it may lead differential pressure and current fluctuation

of boiler water circulation pump. One boiler water circulation pump can be closed acc. to

the situation (pay attention to it and fill the water in time).

5） Each Superheater metal temperature shall be controlled in allowable scope. When

main steam flow ＜ 150T/H, profit using attemperating water. When air steam

flow≥150T/H, if attemperating water is required, control the speed not too fast.

Control attemperating water in min. scope to prevent temperature from sudden drop

and too much stress to damage the equipment.

6） Checking and monitoring instrument staff follow a clear division of

jobs. Prepare necessary repair implement and implement to prevent noise.

Subject to a unified command and insist on jobs.

5.2.8 Main valve and flue gas damper test

5.2.8.1 Test attention:

1） All motorized valve, Electromagnetic valve, control valve, pneumatic valve and flue gas

damper should be done the reliability test before start-up of boiler.

2） Before test, confirm that there will be not any corresponding movement of the medium

and any repair work etc . Safety of equipment, pipes and duct, and personal security can’t

be affected.

3） Before test, do the manual test to confirm machinery part normal.

4） Specified staff is responsible for monitoring.

5.2.8.2 Acceptable standard for test.

1） When doing local manual operation, opening and closing operation is flexible, accurate

and reliable.

2） Opening and closing operation is flexible and limit switch action is accurate when doing

local electric operation.






3） When DCS operator does the test, opening and closing operation is flexible and limit

switch action is accurate. The data on the instrument indicator is consistent

with local actual location.

4） For motorized intercept valve which can be interrupted do the interruption test.

5.2.8.3 Test method and steps:

5.2.8.3.1 Motorized valve check :

1） Confirm that test valve don’t affect operation system. After repair work,

contact with thermal control staff and repair staff should be on site.

2） Valve power has been in service .Signal and indicator is correct.

3） Confirm valve at close position showing the corresponding CRT screen.

4） Put valve manual control at a suitable position of indicator. (keep travel

from the closing direction or opening direction)

5） Motorized test switch is correct. If the valve has “stop” button, test stop

function in service. Limit switch contact and automatic/manual switch also

should be tested in service.

6） Close motorized valve completely and keep remaining travel manually. Thermal

control staff determines break contact for closing direction. Correct local instrument

and CRT screen in the same indicator, and in closed position.

7） Open motorized valve completely. With same method adjust completely

opening remaining travel. Thermal control staff determines breaking signal at opening

direction. Correct local instrument and CRT screen in the same indicator, and in

opened position.

8） Record completely opening period and completely closing period of motorized valve,

travel and remaining travel at opening direction and closing direction.

9） Electric completely open and completely close valve once. Check mechanical dial

of position of indicator, light, signal right. Opening and closing is flexible.

Motor shall automatic trip at the set point, otherwise readjust it again.

10） If test is finished, put valve in position before test.

11） Motorized valve check attention:

A、 When travel limit switch has faults or valve limit body don’t cooperate with travel






limit switch well, pay attention to preventing travel limit switch from out of control

to damage motor and valve. If necessary replace it.

B、 For non-rising stem valve or rising stem valve whose valve stem is difficult to see,

in the adjustment before travel limit switch is set, don’t depend on motor moment

protection action or method of hearing motor surplus air sound to confirm valve

completely opened, completely closed position. Must manually

perform adjustment.

C、 Confirming principle of valve remaining travel :At closing

direction after completely closing valve manual open about 0. 5～1 circle(HP

valve low value, LP valve high value ) or acc. to actual conditions confirm that

open about 90%

of full travel at opening direction and max open position of indicator is 95% of full

travel.

D、 In valve switch test opening and closing button can’t be put at the same time

or the switch can’t be turned from opening(closing)direction directly

to closing (opening) direction to prevent damaging Motor.

E、 If the valve is moment limit valve, never manually operate it after test.

F、 For motorized valve with local, remote control perform full travel test for local and

remote control switch once and the result shall be normal.

G、 Motorized valve with interlock will be performed interlock test to make it normal

after check is finished.

5.2.8.3.2 Control valve test :

1） Confirm that test valve don’t affect operation system. After repair work, contact with

Thermal control staff and repair staff.

2） Gas source and valve power is sent. Confirm that air pressure direction is normal

and opening and closing direction are right.

3） When perform local test, put control valve “manual/automatic” switch

handle in manual position. With rotation hand wheel open and close the full

travel of control valve. The actual conditions must be consistent with

travel indicator in check process. Change the handle to automatic position.

4） Show the corresponding CRT screen. Manually operate corresponding switch of

control valve to separately intermittent and continuous open and close full travel






test once. Check signal, mechanical dial of position Indicator is consistent with the

actual data and control is flexible.

5） Cutting off air test: Cut off air source of control valve, check AO valve automatic

closed after cutting off air source. Check AC valve automatic opened after cutting

off air source. In air cut-off test, prevent system operation from affecting.

5.2.8.3.3 Damper test :

1） Before test, carefully check equipment. If repair work is finished, keep

the site clean.

2） Confirm that test valve don’t affect operation system. After repair work, contact with

thermal control staff and repair staff should be on site.

3） Send relevant air valve, then power of damper, air source, and put

relevant air pressure instrument, negative pressure instrument,

temperature instrument in service.

4） Signal and mechanical dial of position Indicator are normal. Each damper rotation

is good and transmission equipment is also good.

5） Each piece of auxiliary equipment of the system has opening condition.

6） Operate corresponding CRT screen, manually response damper and

separately perform intermittent and continuous opening and closing full

travel once. Check signal direction consistent with mechanical dial of

position indicator and the direction correct.

7） There is not any leaking and other abnormal phenomenon in operating pneumatic

equipment with flexible action and right direction.

5.2.8.3.4 Air fan moving-blade test :

1） Before test, carefully check equipment. If repair work is finished, keep

the site clean.

2） Before test put corresponding hydraulic control oil system in service,

control oil pressure normal and then send control power.

3） Rod and pin of executive body are not loose, bended and exfoliated.

4） Local and main control switch control the moving blade. The direction is right and




the action is flexible. When the position of indicator on the CRT screen is from

0~100%, local position should be consistent with it.

5） Record period and angle of opening and closing full travel in the test.

6） In the process of test, when abnormal conditions occur, stop test, check for the

cause and solve it and then test again till it is acceptable.

5.2.9 Opening, closing and accident button test for auxiliary equipment :

5.2.9.1 Test condition and requirement :

1） After auxiliary motorized equipment and control circuit is repaired, must perform test

for auxiliary equipment switch and accident button.

2） Acc. to repair work requirement, learn the detail in equipment repair content,

abnormal situation, test requirement and scope. Check and confirm

that repair work of mechanical and motorized parts on site is all finished, work-

sheet is recovered and the test condition is had. Then resume relevant system.

3） If empty trial operate the motor, confirm that motor wiring and earthling

cables are complete, backrest wheel disengages and oil quality of bearing

Lubrication position is normal. After check it normal, contact to send the power. In

trial rotation pay attention

to the correctness of rotation direction of motor.

4） Before trial operation of auxiliary equipment, when motor power is cut off,

rotor is without collision and blocking, oil position oil quality is normal, cooling water

valve, seal water valve is opened, outlet and Inlet instruments of primary

damper are opened, pump is filling water to exhaust air is finished, Inlet valve of

centrifugal pump is confirm

ed opened, outlet valve of volume pump is confirmed opened, inlet and outlet valve of

axial pump is confirmed opened. After all the conditions are normal ,do the test.

5） Auxiliary equipment which can be operated on CRT screen and local operation board

should be operated separately.

5.2.9.2 Test method :

1） Contact with electric staff to put 6KV rotation machine switch into test position.

Before test check the correctness of electric, thermal control instrument,

sound and light signal. Confirm operation button and interlock switch is at stopped

position.



2） Before trial-operation of coal feeder, coal feeder inlet and outlet valve should be closed




and coal feeder has no remaining coal.

3） Switch on each rotation machine acc. to normal procedure (A. P, ID

fan, FD fan, primary air fan, seal air fan, mi and coal feeder) once. Each rotation

machine status color should be changed from green to red.

4） In the order of the contrary of above sequence on the CRT screen gradually stop

each rotation machine. Each rotation machine status color should be changed from

red to green.

5） Gradually switch on air preheater, ID fan, FD fan, Primary air fan, and mill and

coal feeder. In the contrary sequence locally put accident button of each rotation

machine. On the CRT screen corresponding rotation machine status

color become yellow, accident speaker sound alarms. If test is finished reset each

switch.

5.2.9.3 Auxiliary equipment protection test :

1） Test condition and requirement :

A. After units are major repaired or minor repaired and auxiliary electric

equipment and control circuit are repaired, must perform auxiliary equipment protection

test.

B. Auxiliary equipment protection test must be performed after auxiliary equipment starting

and stopping test and accident button test is acceptable and meet relevant requirement

for starting auxiliary equipment and accident button.

C. In the test, 6kV can be only operation power. If switch is at test position, 380V auxiliary

equipment is sent as dynamic power.

2） Test method :

A. Stand-by auxiliary equipment shunt opening test :

a) Acc. to normal opening operation, open one piece of auxiliary equipment and check

stand-by auxiliary equipment having opening condition.

b) Put auxiliary equipment interlock switch in service.

c) Turn on accident button to let operation auxiliary equipment trip and send sound

and light alarm signal and stand-by auxiliary equipment is automatic opened.

d) By Using the same method separately test other auxiliary equipment.

If test is

finished, resume auxiliary equipment to the original.






B. Low oil pressure shunt opening protection test for auxiliary equipment oil pump :

a) Acc. to normal opening operation, open one piece of oil pump

and auxiliary equipment and check stand-by auxiliary equipment having opening

condition.

b) Put oil pressure protection in service. Thermal control staff make low oil

pressure signal. When oil pressure is lower than primarily value, stand-by oil

pump will be automatic started. when oil pressure is lower than

secondary value, auxiliary equipment trip and oil pressure data is recorded. If

it doesn’t match the set value, thermal control staff adjust it to match

c) By using same method separately test other auxiliary equipment. If test is finished,

resume auxiliary equipment to original condition.

C. Low water (oil, Air)pressure shunt opening protection test :

a) Acc. to normal operation, open auxiliary equipment and check stand-by

auxiliary equipment having opening condition.

b) When do the low water (oil, Air) pressure protection, Thermal control staff made

low water (oil, Air)pressure signal. When water (oil, Air)pressure is lower than set

value, stand-by auxiliary equipment should be automatic opened

and water (oil, Air)pressure data is recorded. If it doesn’t match the set value,

thermal control staff adjusts it to match.



D. High temperature protection test for auxiliary equipment bearing

a) Acc. to normal opening operation, open one piece of auxiliary equipment.

b) Put temperature protection in service. Thermal control staff made high

temperature signal. When temperature is high primarily value, alarm

signal should be sent. When temperature is higher than secondary

value, auxiliary equipment trips. Record oil temperature data. If it doesn’t

match the set value, thermal control staff adjusts it to match.



E. Water level of protection test




a) Acc. to normal opening operation, open auxiliary equipment.

b) Put water level protection in service. Thermal control staff makes water

level low analog signal. When water level drops to some value, alarm signal should

be sent.

If water level is lower than second value, auxiliary equipment trips. Record water

level. If it doesn’t match the set value, thermal control staff adjusts it to match.



F. Air preheater oil circulation test

a) Thermal control staff make guild bearing oil high temp, analog signal, guild bearing

oil pump should be automatically open and then make guild bearing oil low temp.

analog signal, guild bearing oil pump should be automatically stopped, record oil

temp. data, if it doesn’t match the set value, Thermal control staff adjust it to match.

b) Sing same method to support bearing test.

5.2.9.4 Auxiliary equipment power test :

5.2.9.4.1 Test condition and requirement :

1） If auxiliary equipment is repaired, trial operation must be performed. If trial operation is

good and acceptance inspection is acceptable, it can be put in service or stand-by.

2） Relevant system is confirmed trip or adopts reliable safety measures.

3） Power test of auxiliary equipment should be performed after auxiliary

equipment opening and closing test, accident button test and auxiliary equipment

protection test are acceptable and should meet relevant condition and requirement in

auxiliary equipment protection test.

4） Relevant protection around opening auxiliary equipment should be put in service.

5） Operation and dynamic power of auxiliary equipment should be sent.

6） Before trial operation of FD fan and primary air fan, ID fan should be opened to prevent

furnace from producing positive pressure.

7） Continuous operation period after repair of air preheater, primary air fan, seal air fan,

ID Fan, FD fan is 2—4hour. Empty time of mill should not be more than 10min.

Operation period of other rotation machine should be not less than 30min.






8） When trial operation, relevant mechanical, electric repair staff should be on site.

9） Before trial operation comprehensively check auxiliary equipment.

5.2.9.4.2 Test method and steps:

1） Open Each piece of auxiliary equipment at boiler side in the order of Air preheater, ID fan,

Primary air fan, seal air fan, mill and coal feeder.

2） If equipment in trial operation is abnormal, immediately stop checking the

cause and solve it and then trial operation can be performed again.

5.2.9.4.3 Test acceptance inspection standard :

1） Rotation direction is correct.

2） No abnormal sound, friction and percussive sounds.

3） Bearing temperature and vibration meet in the scope equipment regular value.

4） Equipment system has leaking phenomenon.

5） Equipment output reach nameplate output and motor current shouldn’t be more

than rated current.

5.2.10 Boiler rotation mechanical interlock test

5.2.10.1 Interlock action specification:

1） When main motors of 2 air preheaters are stopped, shunt open air preheater auxiliary

motor, 2 ID Fans trip and boiler MFT trips.

2） When 2 ID Fans are stopped, 2 FD Fan, 2 primary air fans, seal air fan and milling plant

system are shunt tripping.

3） When 2 FD Fans is stopped, 1 ID Fan is shunt tripping, Boiler MFT trips.

4） When 1 Primary air fan is stopped, milling plant system is shunt tripping.

5） When 1 ID Fan is stopped, corresponding side FD Fan is shunt tripping.

6） When 1 FD Fan is stopped, corresponding side ID Fan is shunt tripping. If only one ID

and FD Fan is in service, ID Fan can’t be shunt tripping.

7） Mill is stopped, corresponding mill is shunt tripping, hot air valve is automatically closed

and cold air valve is automatically opened.




5.2.10.2 interlock test method :

1） Put boiler flue gas system master interlock, air fan interlock and each

pulverizing system interlock, air preheater main and auxiliary motor interlock in service

2） Continuously switch on each air preheater main motor, ID fan, FD fan, primary air fan,

seal air fan, mill and coal feeder.

3） Close 1 Air preheater and its auxiliary Motor should be shunt and the other rotation

machines are normal. switch off 2 Air preheaters, MFT should be performed. Primary

air fan and pulverizing system shall shunt trip. Trip rotation machine

CRT screen status color becomes yellow. Accidents speaker alarms, alarm

window lights and reset each trip switch.

4 ） Continuously switch on each rotation machine switch. Stop 1 ID fan,

corresponding side FD Fan shunt trip and the other rotation machine is normal.

Switch off 2 ID Fan, MFT should be performed. FD Fan and the following each

rotation machine should shunt trip. Each trip rotation machine status color

on CRT screen become yellow, accidents speaker alarms, alarm window lights

and reset trip switch.

5） Continuously switch on 2 ID Fan and the following each rotation machine. Switch off 1

FD fan, its corresponding side ID Fan shunt trips, the other rotation machine is normal.

Switch off 2 FD Fan, MFT should be performed, one side ID Fan, 2 Primary air fan,

each rotation machine of pulverizing system shunt trip. Tip rotation machine status on

CRT screen becomes yellow. Accidents speaker alarms, alarm window

lights and reset each trip switch.

6） Continuously switch on 2 ID Fan and the following each rotation machine switch.

Switch off 1 Primary air fan, the other rotation machine is normal. Switch off 2 Primary

air fans, MFT should be performed. Each rotation machine of pulverizing

system shunt trips. Trip rotation machine status on CRT screen becomes yellow.

Accidents speaker alarms, alarm window lights and reset trip switch.

5.2.10.3 Requirement and preparation for rotation mechanical test:

1） Rotation machine with major repair should be performed interlock test and should

be not less than 2 hour trial operation. Before trial operation, confirm rotation machine

and electric equipment and relevant system has no repair work.

2） Shut valve of 6KV rotation machine, accident button and interlock test will only be

static test. Before test contact with thermal control staff, electric staff sends

relevant






operation power and instrument control power and dynamic switch is put on test

position.

3） When in trial operation contact with electric staff send dynamic power.

5.2.11 Boiler MFT test

5.2.11.1 Boiler MFT test, thermal machine and electric support test should be chaired by thermal

control staff.

5.2.11.2 MFT test items are listed as follows: If meet any following condition, MFT trips.

1） Control system power can’t be put in service or air pressure for control is not

correct (3 get 2 pressure), delay 3s and then trips.

2） No ID fan is in service.

3） No FD fan is in service.

4） No air preheater is in service.

5） Total air flow is lower than the lowest( delay 2s and then trips).

6） If water temperature is high and steam exhaust doesn’t exist for more than 6s

or water temperature is not high, furnace gas-temperature probe exits or

furnace temperature is high (delay 6s).

7） No steam exhaust condition (delay 6s and then trips )

8） Drum water level is too low (delay 2s then trips)

9） Boiler water level is too high (delay 60s), and Steam flow is higher than

112%MCR.

10） No circulation pump is in service, delay 2s and then trips.

11） Furnace pressure is high or low.

12） Flame scanner cooling air pressure is too low (delay 600s and then trips)

13） Furnace surge is reset, or all flame scanners fail. If they fail, delay 15s, finally

burners flame scanners fail.

14） Superheating steam pressure is too high (pressure switch), delay 6s and then

trips.

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15） ESP Inlet flue gas temperature is too high, delay 2s and then trips.

16） In load-dump, after delaying T1, steam flow is still higher than x1% of initial flow

before load-dump and only 1 circulation pump is in service.

17） In load-dump , after delaying ts(T1 + T2) , steam flow is still higher than x2% of

initial flow before load-dump and only 1 circulation pump is in service.

18） Any accident button is put.

19） In load-dump, at least 1 coal feeder control circuit is at manual

position and steam flow is higher than y%.

Notice: above x1, x2, y value is per the data on site or is confirmed

by thermal control logical value.


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5.2.12 Drum water level test

5.2.12.1 When Drum water level is higher than first value (+100mm) ,send alarm signal.

5.2.12.2 When Drum water level is raised to protecting value (+200), trigger MFT.

5.2.12.3 When Drum water level is lower than the first value (-240mm) ,send alarm signal.

5.2.12.4 When Drum water level is as low as the protecting value (-425), trigger MFT.

5.3 Check and preparation before start-up

5.3.1 Mechanical check before start-up

5.3.1.1 Before start-up of boiler, must confirm that installation and repair work has been finished,

acceptance inspection is acceptable and all repair work is finished.

5.3.1.2 Each platform, stairs, unobstructed path, railings is firm and integrity, ground is clean, full

of light and fire prevention is complete.

5.3.1.3 No one works in check furnace and duct. Confirm that there is not any implement left,

scaffolding is dismantled., heating surface is cleaned, and refractory belt is complete and

not exfoliated. Switches observation hole and checking hole are flexible and closed

strictly after checking.

5.3.1.4 Insulation of each system (pipes, vessel etc.) is well, hanger is complete, and instrument

is complete and not leaking. Each erosion-proof valve is complete and obstacle is

unobstructed.

5.3.1.5 Air valve, damper and valve are complete. Marks are complete and switch is right and

flexible, direction is clear, remote control equipments is firm.

5.3.1.6 Each expansion indicator is complete with right location and pilot graduate is clear and

correct. Pointer is without jam and record defaults.

5.3.1.7 Burners have good heat insulation. Duct and blast box has no dash, oil and debris to

obstruct expansion of blast box.

5.3.1.8 Burning oil system and steam to purge, oil burners, igniter and control system are

complete and can be put in service.

5.3.1.9 The ash handling equipment is available for service, soot blower transmission is flexible,

the location is showed correctly, and at exit position.

5.3.1.10 Furnace gas-temperature probe retracts flexibly and is put in service. Furnace flame

monitor and cooling system is complete.




5.3.1.11 Local water level is clear and in service, opening and closing steam valve is flexible and

not leaking. It is full of light and camera system is complete and can be put in service.

5.3.1.12 Safety valve and ERV are complete, steam exhaust is unobstructed and fixed.

5.3.1.13 Inform dash, chemical, combustion operation staff of comprehensively checking each

system, preparing for start-up and having the start-up condition.

5.3.1.14 Check for each auxiliary equipment, rotation machinery and auxiliary equipment is

acceptable. Mechanical parts is with no jam, Lubrication quality is acceptable and oil is

full. Cooling water, seal water and etc. are normal.

5.3.1.15 Check each valve, air valve is in open position.

5.3.1.16 Raw coal and pulverized coal bunkers are filled and available.

5.3.1.17 HFO is available. The associated heat tracing and pretreatment system have been

checked and are available for service.

5.3.1.18 The ESP is available and ready for service. The rapping and the insulator heating

systems are in service. Low temperature or low level alarms are cleared.

5.3.2 Thermal control and electric check before start-up:

5.3.2.1 In center-control room, there is full of light and accident lighting is reliable.

5.3.2.2 Each instrument is sent the power, operation switch and change-over switch, Light of

indicator are complete.

5.3.2.3 Open all transmission and sample valve for signal pipe of measuring instrument and

close blow down valve.

5.3.2.4 Alarm equipment, protection panel, control panel and each monitor instrument, record

instrument and printer are normal and put in service.

5.3.2.5 DCS station is normal. The data on CRT screen and instrument is consistent with

equipment actual status.

5.3.2.6 Check all safety interlock equipment in service. Confirm interlock protection for CCS,

FSSS, PLC, DAS etc. correct.

5.3.2.7 Each piece of auxiliary equipment Motor has good insulation.

5.3.3 Test and prepare before stat-up :

5.3.3.1 All the main test before start-up of boiler:

1. Opening, closing position test for valve and damper




2. Static opening, closing, change-over and accidents button test and interlock

logical test.

3. Gang test for auxiliary equipment.

4. Gang test for auxiliary equipment lubrication pump.

5. Air preheater drive equipment test.

6. Boiler interlock protection test i.e. MFT condition test.

7. Turbine, boiler and generator big interlock logical protection test.

8. Other test acc. to repair conditions.

5.3.3.2 Confirm that each valve, air valve, damper meet the requirement.

5.3.3.3 Each auxiliary equipment power and operation power are sent. Each instrument get

power and control power.

5.3.3.4 Put industry water system in service, check operation normal.

5.3.3.5 Open air compressor system, check system operation normal, and keep compressed air

pressure above 0. 65Mpa.

5.3.3.6 Contact with neighbor unit or start up boiler to supply auxiliary steam header with air, and

keep pressure about 0. 525Mpa.

5.3.3.7 Check and put oil circulation of burning oil system in service. Put purging steam in

service to heat the pipe and drain to clean.

5.3.3.8 Put water seal at boiler bottom and fully fill water.

5.3.3.9 According to oil temp conditions, put electric heater in service. If oil temperature is

consistent with the regular, open oil equipment of each mill and air peheater, FD fan oil

station. Acc. to temp. of Oil in Oil tank, put cooling air fan of ID fan in service.

5.3.3.10 At the 12th hour before igniting the boiler, put ESP ash box heating automatic. At 2nd

hour before igniting the boiler put ESP rapping in service

5.3.4 Initial firing precautions:

5.3.4.1 To insure a maximum safety margin during start-up, an air flow of at least 30% of full load

air must be maintained in order to produce the following conditions:

1） An air-rich furnace atmosphere




2） To avoid the possibility of accumulation or stagnation of explosive mixtures in the

event of poor or delayed ignition after fuel is introduced to the Furnace.

5.3.4.2 As the boiler load is increased, the operators shall check that the air flow is increased to

maintain the design operating excess air. A periodical verification should be made. Refer

to the curve “Design excess air versus boiler load” at the end of this section.

5.3.4.3 Never attempt to light a burner without its associated igniter or without atomizing

/scavenging medium available.

5.3.4.4 If combustion hasn’t started within 15 seconds after the fuel is fed to burner nozzle the

fuel should be cut off and a furnace purge during 5mn should be performed again.

5.3.4.5 During start-up, the boiler firing is done preferably with the oil burners located at the

center of the arch. The required firing rate shall be adjusted to operate without exceeding

the maximum allowable furnace exit gas temperature of 550 °C.

5.3.4.6 As an addition, in order to maintain the Furnace exit gas temperature below 550℃,the

necessary fire rates to obtain the required pressure rise gradient are approximately the

following(airflow% refers to the airflow MCR):

1） 6 % of the BMCR firing rate with an airflow of about 30% during the first stage of the

pressure rise.

2） When the pressure rise slows down, the firing rate can be

increased by approximately 12 % of the BMCR with airflow of about 40%.

5.3.4.7 When the boiler is being warmed up, the saturated steam temperature rise gradient must

be limited to 100 °C/hour during the first hour and to 110°C/hour during the second hour.

Note: It is recommended to follow the shower rate of temp. increases during the initial

start-up of a new unit or after repair works in Furnace This will allow sufficient time for

drying the refractory, checking the expansion movements and to allow the operators to

become familiar with the characteristics of the steam generator and its auxiliaries.




5.3.4.8 The boiler limits shall not be exceeded. Consult the start-up curves and diagrams given

at the end of this section.

5.3.5 Superheater and reheater protection during cold start-up :

5.3.5.1 This is especially important when there is no demand for steam such as when starting up

and shutting down. During the periods when there is no steam flow through the turbine,

an adequate steam path shall be ensured.

5.3.5.2 During start-up, the superheater is protected by the steam flow passing through the HP

bypass and the reheater is protected by the steam flow passing through the start-up vent

or through the LP by-pass. It is considered that the minimum steam flow required for a

proper protection is 10% of BMCR (approx. 100t/h).

5.3.5.3 During the first phase of the boiler start-up, the generated steam flow is insufficient to

cool down and protect the superheater and reheater elements from high flue gas

temperature. Therefore, particular care must be taken not to overheat the exchangers.

5.3.5.4 In order to protect the superheater and reheater until a sufficient and continuous steam,

the firing rate must be controlled to keep the maximum Furnace exit gas temperature

from exceeding 550

5.3.5.5 When the steam flow is established above the minimum required (steam flow approx

100t/h), the thermocouple probe may be retracted and the firing rate increased. However,

care must be taken to ensure that the totality of the steam flow crosses the reheater, i. e.,

that there is not any auxiliary steam from cold reheater pipes.

5.3.5.6 When steam is taken from cold reheat to feed the auxiliary steam header, never take

more than 20% of the steam flow through HP by-pass during start-up phases.

5.4 Cold start-up sequence

If the period after shut-down is more than 40 hour or remnant drum pressure is lower than 20

bars, it is called cold shut-down.

At Design condition estimated period of cold start-up to full load is 6. 5hour.

5.4.1 Boiler filling

5.4.1.1 If checking work before igniting the boiler is finished, after getting boiler of filling water,

Boiler can be filled and the requirement for boiler filling is as following :

1） Confirm all valves of steam system in right position.

2） Clean the system before filling the boiler. Water quality should be assayed


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Đối chiếu với điều kiện cold start/hot start của tuabin



acceptable. Water temperature is decided acc. to drum wall temp. Try

decreasing differential temp. If it is large, the speed of filling shall be

slow to prevent drum, header and etc. from producing too big hot stress.

3） 3 boiler water circulation pumps are filled water. Air exhaust is finished. Motor

cooling water system are put in service and the cooling water is adequate.

4） Economizer recirculation valve has been opened.

5） Open feedwater bypass motorized valve.

6） Locally open 3 boiler water circulation pump outlet valve.

7） Boiler filling period should be controlled in: Sumer≥２hour, Winter ≥4 hour.

5.4.1.2 Condensate of boiler filling or dematerialized water quality should meet requirement :

Condensate water dematerialized water

Form colorless hardness 0mmol/L

hardness ≤0umol Conductivity ≤0. 5us/cm

Fe ≤1000ug/kg SiO2 ≤20ug/L

Cu ≤200ug/kg pH 9


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hình như nước này được lấy từ nước ngưng Xem lại thế nào!!!!



5.4.1.3 Temperature of filled water is higher than 20℃ and approach drum wall temp as possible

as it can. The differential temperature of water temperature and drum wall temperature

shall not be over about 28℃.In the process of filling, the differential temperature of drum

upper and lower wall temp can’t be higher than 40℃.

5.4.1.4 Acc. to requirement of filled water temperature required by drum wall temp, open

condensate water pump or steam booster pump (or motorized pump) through feedwater

bypass to fill boiler till economizer air damper overflow water and then close valve

economizer air damper.

5.4.1.5 Open feedwater bypass valve and adjust water pump rotation speed to fill the water

smoothly. Control filling water speed. If water temp approaches drum wall temp, add the

speed suitably. But Drum wall differential temp. can’t be over set value.

5.4.1.6 When water level rise to lowest water level on the drum local water level instrument, turn

down feedwater control valve, control filling speed to let water level rise to high water

level slowly. If perform superheater hydraulic test, continue filling till each air damper of

superheater continuous overflow water and then close each air damper.

5.4.1.7 If filling is finished, close each water intake valve, stop water pump, and monitor drum

water level should be kept constant, otherwise it is required that checking for the cause

and reporting to the shift supervisor.

5.4.1.8 When filling boiler, 3 boiler water circulation pump Motor room continues keeping filling

water till boiler water circulation pump finishes air exhaust, boiler is ignited and pressure

rise to 2. 07MPa and then stop filling water.

5.4.2 Boiler cold igniting pressure rising

5.4.2.1 Start 2 boiler circulating pumps, and readjust drum level to approach the low level if

necessary. Select the third pump in hot stand by.

5.4.2.2 Open the air and gas path, that means:

1） Start both air heaters

2） In the sequence open the breaking damper at burning air outlet.

3） Put the flame scanner cooling air system and the fuel-oil burner

sealing air system service.

4） Start one I. D fan and put the furnace pressure in automatic.

CAUTION: The ID fans are able of developing excessive drafts that may damage


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Đây là điều chỉnh quá trình điền nước lò Xem kĩ thế nào!!!

Sony

Cross-Out

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Underline

Sony

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sealing air hay cooling air ?

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Sony

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Sony

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Vậy lúc nào điền trở lại??? Đây là điền nước làm mát cho động cơ bơm tuần hoàn lò,nước này sẽ chạy tuần hoàn trong thân đông cơ và trao đổi nhiệt với bộ làm mát.

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Polygonal Line

Khi nào khởi động lại



part of the air/gas circuits. Care shall be taken to establish and maintain an open

air/gas path through the unit prior to starting an ID fan. Ensure that:

Air dampers to HFO burners are in open position;

The balancing dampers of secondary air compartments are not closed;

The shut off damper and the control valves of at least one FD

fan are opened.

5） Start one F. D fan.

6） Take care, during starting the first FD fan to maintain opened the shut-off damper

and control valves of the other FD fan.

7） Increase the secondary air flow at the minimum required, i. e. 30% of full load

airflow.

8） Successively start the second ID fan and the second FD fan.

9） Put in automatic control all the fans and combustion airflow command.

10） Put in automatic control the air dampers on secondary and tertiary air circuits

FCA/B PCV 11A, 11B, 11C, 21A, 21B, 21C, 14, 15, 24,

Check the following recommended positions

FCA/B PCV 11C and 21C are opened 100%

FCA/B PCV 11B and 21B are opened 20%

FCA/B PCV 11A and 21A are closed

FCA/B PCV 14, 15, 24 and 25 are closed




5.4.2.3 Start the steam air preheaters (if auxiliary steam is available) and verify that the

temperature set point is in automatic.

5.4.2.4 Start both primary air fans and put PA pressure control in automatic control.

5.4.2.5 Put in service the retractable probe.

5.4.2.6 Open the reheater start-up vent FRS UV 01.

5.4.2.7 Open the economizer re-circulating valve FSR UV 002.

5.4.2.8 Open the rear pass and ITS drain valves FSR UV 003 and 005.

5.4.2.9 Verify that the cold reheat drain valve FRS UV 002 is in automatic

5.4.2.10 With airflow of 30 % of nominal flow, perform a Furnace purge during 5 minutes.

“Soot blowing allowable ”condition :

1) Whole security of the units is established. I.e. control system power is in service,

air pressure of instrument is normal.

2) At least one ID fan is in service.

3) At least one FD Fan is in service.

4) Close all oil burners.

5) Pulverized coal feeder is in service.

6) All ESP system is shut down.

7) All flame scanners don’t scan flame.

8) Close burning oil main closure valve.

9) Close all pulverized coal burners, i.e. primary air damper is closed.

10) Burning improving air valve of burners is at purge position (open specified air valve,

close other valve ).

11) Total air flow (primary air and secondary air) is from 25% to 40% BMCR flow.

Furnace purge is correct, and then ignite burning oil burners.

In furnace purge time if any condition can’t be reached, purge will be stopped; 5

min timer must be reset.


Sony

Underline

Đã mở ở dòng thứ 4) trang 96 rồi mà? Có phải là việc điền nước lò và việc đưa hệ thống khói gió và làm việc có thể làm đồng thời hoặc cái nào trước cũng đươc,tùy theo...!

Sony

Underline

Máy cấp than mịn có liên qua đến quá trình thổi bụi thế nào vậy?

Sony

Rectangle

Thổi bụi...?

Sony

Underline

Nếu ko mở bypass LP thì van này có thể tạo đường hơi tuần hoàn qua bộ tái sấy.

Sony

Underline



In furnace purge time, finish burning oil circuit leaking test. If “ leaking test is not

finished ” or “leaking test is abnormal” , need reset furnace purge end storage. Check

the cause for failure, re-perform a furnace purge.

5.4.2.11 Check the boiler safeties setting conditions.

5.4.2.12 Open the boiler isolating valve and the HP by pass. Place the HP by-pass in auto with

the HP pressure set point at 60 bars. This will position the HP by pass at a constant

opening (minimum start-up opening, around 20%).

5.4.2.13 Start one after the other, 2 oil burners at the centre of the arch (FBI+FBN or FBH+FBF),

and check locally the correct operation of the burners and the quality of the combustion.

“Furnace igniting allowable” condition:

1） Boiler purge is finished and “Purge end storage” is set up.

2） Control system power can be put in service and air pressure for

control is correct.

3） At least one ID Fan is in service.

4） At least one FD Fan is in service.

5） At least one air preheater is in service.

6） Total air flow is higher than min value.

7） Boiler drum water level is not at high position.

8） Drum water level is correct, i.e. above too low water level.

9） At least one circulation pump is in service, i.e. pump works (Motor contactor

auxiliary switch) and relevant differential pressure is higher than min value.

10） Furnace pressure is correct, i.e. between the highest and lowest

(pressure switch 3 get 2).

11） Flame scanner cooling air equipment is in service, i.e. cooling air is higher than

min value.

12） Superheater outlet steam pressure is not too high (3 get 2).

13） ESP Inlet Flue gas temperature is not too high.


Sony

Underline

Hình như trên hệ thống của NMNĐQN ko có van này?



14） Accidents button is not put.

15） If water temp is high and steam exhaust exists or if water temp is not high,

Furnace gas-temperature probe is in service and furnace temperature

is not high.

Notice: required condition for steam exhaust:

Open HP cylinder steam intake valve (Open emergency closure valve and close

turbine control valve) and open boiler outlet closure valve (close limit switch).

HP bypass in not close :

LP bypass valve is not closed.

IP steam intake valve is opened (close limit switch) and HP control valve is not

closed.

Open reheater outlet air draft valve (no closure, limit switch is switched on, no

action).

If all conditions are met, boiler total safety storage can be automatically set up,

and then the burners can be put in service.

“Oil supply to oil burners allowable” condition:

1） Oil pressure is normal.

2） Meet conditions for furnace igniting allowable or any burners is ignited.

3） No MFT condition.

4） No OFT condition.

5） Oil burner’s secondary air damper is at igniting position.

6） Oil a burner steam purge valve and oil valve is closed, oil burner and igniting

burner exit, oil burner power is normal.




5.4.2.14 If necessary adjust the firing rate. During pressure rise control the firing rate to keep the

maximum furnace exit gas temperature below 550 °C. The rising rate of saturated steam

temperature is about 100 °C/hour during the first hour and to 110°C/hour during the

second hour. The pressure rise of the boiler meets relevant requirement. (see start-up

curve).

5.4.2.15 When the drum pressure increases above 2 bar, close the ITS and motorized drain valve

of the rear pass.

5.4.2.16 As the water in the boiler is warmed up and expands, the level in the drum will increase.

If it is required, open the intermittent blow down valve at the circulating pumps outlet to

decrease and maintain normal water level in the drum.

5.4.2.17 Increase the firing rate. Start more oil burners if it is required. Continue surveying the

furnace exit temperature (<550°C) and the gradient of the saturated steam temperature

(<110 °C/hour).

5.4.2.18 Put feed water control valves in automatic as soon as possible. At this stage, the drum

level is controlled by the start-up valve FSR-LCV-52D.

5.4.2.19 Close the economizer re-circulation valve, as soon as a permanent feed water flow

above 100t/h is established.

5.4.2.20 When the steam flow rate is above 100 t/h, stop the retractable probe.

5.4.2.21 When vacuum is established in the condenser, put in service the LP bypass with and set

the reheater pressure set point to 8 bar. Close the reheater start-up vent when the LP

by-pass starts opening.

5.4.2.22 Check that spray water valves are in automatic and that temperature set points are in

accordance with turbine rolling requirements.

5.4.2.23 As soon as the reheated steam conditions are within the required value, start turbine

rolling

5.4.2.24 When HP pressure reaches 60 bar, the HP by-pass switches from minimum opening

position to automatic pressure control mode. The by pass opens to control the HP

pressure at 60 bar.

5.4.2.25 The Boiler pressure control is in automatic, manually continue increasing the firing rate

by adjusting oil pressure and/or adding burners to obtain a steam flow of 200 t/h. For

information, at this stage 10 to 12 oil burners are expected to be in service.

5.4.2.26 Start the electrostatic precipitator.


Sony

Underline

Van này nằm ở đâu vậy ta?

Sony

Underline

Nói vậy có nghĩa là nãy giờ van bypass hạ áp chưa mở!!! Tới lúc này vẫn chưa mở(đưa vào làm việc ko có nghĩa là đã mở.hehe) bypass LP mở khí áp suất tại bộ tái sấy >= 8 bar

Sony

Underline

Bước này là để đảm bảo hơi quá nhiệt 560C và nhỏ hơn 4270C

Sony

Underline

Nói vậy có nghĩa là : 1.Không phải là van bypass LP mở ngay khi hoăc trước khi đốt lò 2.Phải đóng van xả vent của bộ tái sấy khi van bypass bắt đầu mở,vì nếu vẫn ko đóng thì không khí sẽ vào lại hệ thống theo đường xả vent vì áp suất bình ngưng âm

Sony

Rectangle

Chỗ này thấy hay hay nhưng ko hiểu lắm!

Sony

Cross-Out

Sony

Rectangle



5.4.2.27 When steam flow is >200 t/h, prepare to put pulverized coal burners in service if the coal

silo has pulverized coal. One rotary coal feeder can be started when the permissive

conditions are met.

5.4.2.28 Continue monitoring superheating/reheating steam conditions and prepare for turbo and

generator synchronization.

5.4.2.29 When feed water flow is above 200 t/h open feed regulating valve and differential

pressure is lower than 5 bar . The main feed valve LCV52 takes over drum level control.

5.4.3 Rolling of the turbine and synchronization

5.4.3.1 When the boiler load is around 20% (steam flow 200 t/h), the HP steam pressure is 60

bar, the LP pressure 8 bar. As soon as HP/LP steam temperature conditions are

satisfactory, the turbine can be rolled up.

5.4.3.2 During speeding up of the turbine, the boiler is maintained at constant steam flow 200 t/h.

Maintain steam temperature at 400 °C on HP side and at 390 °C on IP side.

5.4.3.3 When the turbo-generator warm-up is completed and permissive conditions are met

steam is introduced to the turbine.

5.4.3.4 The HP by-pass is closed gradually to let the turbine HP cylinder take over the

superheated steam flow.

5.4.3.5 The LP by-pass closes gradually to let the turbine IP and LP cylinders take over the

reheating steam flow to the turbine and generator are synchronization.

5.4.4 Load rise

5.4.4.1 The maximum boiler load that can be achieved with oil burners can reach 30% at most

5.4.4.2 When steam flow is higher than 200t/h, start one rotary coal feeder and after stabilization

start a second one on the opposite side of the Arch nose. The associated oil burners

should be in service to ensure ignition of the pulverized coal.

5.4.4.3 Adjust the secondary air distribution in the arch compartments, in order to obtain diving of

the flames (the control stations of dampers FCA/B PCV 11A/B/C and 21A/B/C are

operational as soon as a rotary feeder is in service)

5.4.4.4 When steam flow is higher than 250t/h start the milling plant if require.

5.4.4.5 Start more coal burners according to load and pressure rise. The total coal demand can

be put in automatic and the firing rate can be then controlled by the boiler load demand

set point.


Sony

Line

Sony

Underline

Trong giai đoạn này van bypass HP và LP sẽ được điều chỉnh sao cho áp sất hơi HP=60bar và hơi LP=8bar

Sony

Oval

Hình như điều kiện nêu ra ở đây thỏa mãn cả 2 phương pháp xông hơi!!!

Sony

Underline

Nghĩa là tuabin được sấy xong=đảm bảo các điều kiện về độ chênh nhiệt độ,độ giãn nở. - Thời gian bao lâu? - Giá trị độ chênh,độ giản nở là bao nhiêu?

Sony

Line

Sony

Underline

tới 200t/h thì bắt đầu đốt than

Sony

llll

diving of the flames

Sony

Underline

là giá trị 600v/p và tốc độ tăng tốc 100v/p

Sony

Underline

Chắc là xác định theo các curve

Sony

Line



5.4.4.6 When the HP by-pass is closed, raise the pressure gradually by controlling the firing rate.

The saturated steam temperature gradient shall remain below the Design limits (see

start-up curve).

5.4.4.7 Keep the fuel-oil burners in service as long as required and until the expected numbers

of coal burners are operating. Furthermore, it is recommended to keep in service 4 oil

burners after reaching full load to obtain a stabilized temperature on the refractory.

5.4.4.8 Transfer the turbine control and the boiler load demand to automatic. Under this mode

the unit is in the coordinated mode selected by the operator (boiler or turbine following).

Normally the boiler following mode is used: the opening of the turbine valves controls the

load and the firing rate controls the steam pressure.

5.4.4.9 Put the steam temperature control in automatic. Verify that correct set points have been

reached.

5.4.4.10 Check the total airflow which has to be sufficient at all times for the actual firing rate.

5.4.4.11 When the target load is reached, verify that boiler-operating conditions are in

conformance with design data. Refer to expected values and to the sliding pressure and

excess air curves.

5.5 Hot start-up

Hot status boiler is classified as the following types:

• Moderate: Shut-down for 10 to 40 hour, boiler pressure is from 2. 0 to 6. 5 MPa.

•hot: shut-down for 1 to 10 hour, boiler pressure is from 6. 5 to 14. 0 Mpa.

• Extremely hot: shut-down for less than 1 hour, boiler pressure is higher than 14. 0 Mpa.

5.5.1 Check and preparation before hot start-up:

5.5.1.1 Control air source, power is reliable, and control air source pressure normal.

5.5.1.2 Fire scanner and fire-proof system is normal, Air preheater fire extinction equipment is

reliable.

5.5.1.3 Put water seal at boiler bottom in service. Filling water, each piece of equipment of ash

handling system is at stand-by status.

5.5.1.4 Burning oil system and atomization steam system is normal.

5.5.1.5 The following equipment operation is normal, If it is stopped, open it again :

1） 2 Air Preheater.


Sony

Line

Trời ơi!Mình nhầm... boiler following = lò theo,chứ không phải = theo lò boiler following : van GV cứ việc điều chỉnh tải(~ lưu lượng hơi),còn áp suất hơi thì lò phải điều chỉnh theo.



2） AC flame scanner cooling air fan, DC air fan are at “interlock”.

3） 2 boiler water circulation pump, and stand-by pump is at “interlock”.

5.5.1.6 The following auxiliary equipment is at stand-by status

1） A, BID Fan

2） A, BFD Fan

3） A, BPrimary air fan

4） A, Bpulverizing system

5） All pulverized coal feeder and oil burner

6） A, BSteam air preheater

7） A, B ESP

5.5.1.7 All soot blowing burners position are correct and at “exit” position.

5.5.1.8 A, B Furnace outlet flue gas temperature probe has been put in service.

5.5.1.9 A, B Furnace flame TV has been put in service.

5.5.1.10 Steam system check is finished and its valve position meets the requirement before

igniting the boiler:

1） Close all air damper of superheater and drum.

2） Open economizer recirculation valve.

3） Open atmospheric relief valve at reheater outlet.

4） Automatic drain valve at cold reheater main pipe is reliable.

5） Each manual valve of attemperating water system is opened, each

motorized valve, control valve are closed.

6） Main steam valve and bypass valve are closed




5.5.1.11 Close the left drain valve of superheater.

5.5.1.12 Check that drum local or TV water level instrument has been put in service and drum

water level is normal.

5.5.1.13 Each valve position of soot blowing system is right.

5.5.2 Boiler hot start-up steps：

5.5.2.1 Open opening vent valve FRS UV 001 of the reheater.

5.5.2.2 Make sure that there is no drain opened in reheat pipe and automatic drain valve FRS

UV 002 is available and ready for service.

5.5.2.3 Open during a sufficient time (see table) the automatic drain valves on superheater:

1） Drain valve of steam walls of rear pass FSR UV 003.

2） Drain valve of LTS inlet FSR UV 005.

3） Drain valve of superheater outlet steam pipe FSR UV 004.

4） The drains have to be opened before firing the boiler during a time long enough

to eliminate all the water out off the superheater. The time is function of the duration

of the shut down and the pressure in boiler. Follow the indications here below

Residual drum pressure (bar) 150 80 50 10

duration of opening (mn) before firing:

- FSR UV 003 2 5 10 65

- FSR UV 004 2 5 10 60

- FSR UV 005 2 5 10 60




5.5.2.4 Open drains and conditioning devices of the main steam lines according to the

instructions of the turbine manufacturer.

5.5.2.5 Start, one side after the other, the ID and FD fans.

5.5.2.6 Start the steam air preheaters.

5.5.2.7 Start one after the other both PA fans and put PA pressure control in automatic.

5.5.2.8 Adjust the airflow to 30 % of nominal flow and perform Furnace purge during 5 minutes.

5.5.2.9 Open the HP by-pass gradually by adjusting pressure set point below the actual

remaining pressure.

5.5.2.10 Start 2 diagonals of oil burners as soon as possible.

5.5.2.11 According to turbine conditions, maintain or raise boiler pressure by adjusting HP

by-pass set point and increasing firing rate.

5.5.2.12 Close the economizer recirculation valve, as soon as a permanent feed water flow is

established and put in automatic the drum level control.

5.5.2.13 When the vacuum is established in the condenser, put in service the LP by-pass and

close the reheater start-up vent.

5.5.2.14 Steam flow and steam temperatures will rise rapidly in relation with the firing rate.

5.5.2.15 Open main steam line warm-up lines and boiler stop valve according to turbine

manufacturer. When turbine start-up conditions are reached, start rolling the turbine.

5.5.2.16 Start the Electrostatic precipitator.

5.5.2.17 After synchronization, raise the load by putting in service additional burners. Check

proper airflow.

5.5.2.18 Control firing rate to obtain the load acc. to raise startup curve gradient (110°C/hour).

5.5.2.19 Put the steam temperature and load controls in automatic.

5.5.2.20 Check that firing conditions are stable. Check that pressure and temperature set points

are reached.

5.5.3 Boiler star-up attentions :

5.5.3.1 Metal wall initial temperature and other relevant parameter of turbine HP and MP cylinder

and boiler status decide the start-up status of the unit.

5.5.3.2 In strict accordance with start-up curve of each status, raise temperature and pressure.




5.5.3.3 When raise the pressure, pay attention to the changes of steam and water quality.

5.5.3.4 When oil is burning, close monitor the changes of temperature of air preheater outlet flue

gas.

5.5.3.5 In the process of start-up, pay attention to burning conditions, especially oil burning.

When each oil burner is put in service, out of service and normal operation, strengthen

the check for oil burner. If oil burner has oil leaking, bad atomization, when oil is leaking,

immediately take measures to solve. When oil burner is stopped, close burning oil input

manual valve, if the defects can’t be solved, “prohibit opening” marks should be put on it.

5.5.3.6 Check the reliable operation of flame scanner equipment at any time.

5.5.3.7 Check economizer protection, i.e. the using condition of economizer recirculation valve.

5.5.3.8 Check protection for superheater and reheater and can’t allow operation of steam with no

path. Pay attention to monitoring metal wall temp. in the allowable scope.

5.5.3.9 For the oil with primary start-up or with major repair, confirm boiler hot expansion of each

parts, especially the low hot expansion. Record each data of boiler expansion indicator

for reference of start-up.

5.6 Parameter control value In the process of start-up

5.6.1 Parameter which should be controlled in boiler cold start-up

Time(min )

Parameter

Units

0 60 144 255 390

Main steam pressure bar 0 6 60 60 167

Main steam temperature ℃ ／ 260 400 400 541

Reheat steam temperature ℃ ／ 240 390 390 539

Main steam flow t/h 0 0 200 200 995

unit load MW 0 0 0 15 300

specification boiler igniting turbine impulse starting synchronization full load

5.6.2 Parameter which should be controlled in boiler hot start-up

Parameter Units Time(min )




0 20 50 60 110

Main steam pressure bar 0 78 100 100 167

Main steam temperature ℃ ／ 400 480 480 541

Reheat steam temperature ℃ ／ 380 460 460 539

Main steam flow t/h 0 120 300 300 995

Unit load MW 0 0 0 15 300

specification Boiler igniting turbine impulse starting synchronization full load

6 Monitoring and adjustment in boiler operation

6.1 The main task and objectives of operation adjustment

6.1.1 Keep evaporative capacity of boiler is in the rated value and meet the requirement of unit

load.

6.1.2 Maintain normal and stable steam pressure, steam temperature and drum water level.

6.1.3 Maintain water and steam quality acceptable.

6.1.4 Keep good combustion, raise boiler efficiency and keep the furnace clean.

6.1.5 Ensure that boiler and subsidiary equipment should be opened, stopped safely and

operated economically and safely.

6.2 Main Parameter and limit of operation control

6.2.1 Different load operation control main Parameter value:

Coal burning(load ) Item

Units

BMCR RO

75%

RO

60%

RO

Min load

*60% RO

1. Generator total

output power

MW

300

225

210

2. Steam flow kg/H

(a) Superheat steam 995 882. 7 639. 4 518. 9




(b) Reheat steam 849. 4 756. 5 555. 0 443. 8

3. Steam pressure kg/cm2g

(a) Drum 190. 4 186. 5 156 127. 5

(b) Superheat steam 176. 3 174. 7 149 121. 9

(c) Reheat steam 33. 7 30. 1 22. 1 18. 0

4. Steam temperature ℃

(a) Superheat steam 541 540 539 539

(b) Reheat steam 538 538 538 538

5. Feedwater pressure kg/cm2g

(a) Economizer Inlet 193. 9 189. 4 158. 7 129. 9

6. Feedwater temperature ℃

(a) Economizer Inlet 281 273 254 243

7.Fuel consumption (coal) kg/H 129500 99100

8. Air temperature ℃

(a) Steam air preheater

Inlet

29

29

29

29

(b) A. P outlet Primary air 356 352 324 308

(c) A. P outlet

Secondary air

333

333

311

297

(d) Mill outlet 110 110 110 110

9. Flue gas temperature ℃

(a) Superheater outlet 670 650 610 580

(b) A. P Inlet 400 392 358 340

(c) A. P outlet 124 121 111 102




10. O2 content in Flue gas % Vol

(a) Economizer outlet 4. 0 4. 0 4. 5 5. 4

(b) A. P outlet 5. 1 5. 1 5. 9 6. 8

6.2.2 Limited value of boiler operation main Parameter control :

Parameter Name Units Setting value range

Superheat steam pressure bar 175±5 ±2

Superheat steam temperature ℃ 541±5 ±2

Reheat steam temperature ℃ 538±5 ±2

Drum water level mm




6.3 Checking, monitoring and maintenance in boiler operation

6.3.1 Checking in boiler operation :

6.3.1.1 Intermittently check each operation parameter and equipment operation conditions in

DCS screen in boiler normal operation. If there are abnormal parameters or abnormal

conditions of equipment, immediately analyze and take corresponding control measures.

6.3.1.2 Intermittently check equipment operation conditions in boiler normal operation. If there is

abnormal vibration, abnormal sound or coal leaking, pulverized coal leaking, air leaking,

steam leaking or oil leaking etc. in equipment operation, immediately take isolation

measures.

6.3.1.3 Often analyze each operation parameter, comparative analysis of each data of indicator

of equipment on site and each parameter from DCS. If there is any doubt or big errors,

the cause must be checked carefully and solved.

6.3.2 Combustion control of boiler:

6.3.2.1 In boiler operation immediately control coal quality condition fed to the furnace and per

coal quality condition, adjusts mill outlet temperature and differential pressure between

inlet and outlet.

6.3.2.2 In operation close monitor change of air flow and oxygen content of flue gas. At any time

air flow should be more than lower than 30% BMCR operating condition, keep Flue gas

oxygen content in suitable scope.

6.3.2.3 Often check burning condition in the furnace and observe fire condition pulverized coal .

6.3.2.4 When furnace burning is not stable, immediately put oil burner in service for stable

burning. When Boiler load is lower than 60% BMCR, input oil for stable burning.

6.3.2.5 When raise load, crease air flow and then crease fuel. When drop load, decrease fuel

and then decrease air flow

6.3.2.6 Intermittently check total air flow for boiler burning, adjust to keep appropriate rate of air

/coal to reach good burning operating condition.

6.3.2.7 Acc. to coal quality and burning condition, adjust the position of air valve of air

adjustment and axial blade, keep reasonable pressure drop of burners and alternate

secondary air rotating speed to confirm degree of disturbance of mixture of air and

pulverized coal.




6.3.2.8 Acc. to boiler combustion system each parameter and steam temperature change trend

immediately adjust the position of indicator of secondary air dampers at front, rear arch A,

B, C row, and minor adjust the position of indicator of each upper and lower tertiary air

valve of front and rear wall to change the length of W flame.

6.3.2.9 Good burning operating condition is that “fuel －air” mixtures is burning in furnace lower

parts, i.e., the mixtures stay longer in the furnace with full of flame which is golden yellow.

If oil is burning, flame is white and light. And don’t impact water wall and plate

superheater. Ignition point of fuel can’t be approached which can cause burners burned

and damaged by around coking easily. And incompletely burned fuel content in ash and

fly ash is low.

6.3.2.10 Turn up external secondary Air damper. Flame ignition point of pulverized coal becomes

remote; Otherwise, turn down external secondary Air damper, ignition point of fuel

become near. Add external secondary air flow and carbon content in the fly ash is

obviously decreased but maintain burning safety at the same time. The final setting value

for the position of indicator of external secondary air shall be a little smaller than critical

position of indicator.

6.3.2.11 Internal secondary air damper should be decreased to make flame closer and make

critical position of indicator of external secondary air become large and make burners air

flow’s direction to external secondary air to make it economical.

6.3.2.12 If burning flame is instable, check primary air flow. Big air flow and thick pulverized coal

will cause flame instability. Otherwise, too low primary air flow may cause pulverized coal

uneven distributed in burner tips to lead burning disturbance.

6.3.2.13 In normal operation, keep furnace negative pressure -100Pa.

6.3.2.14 Furnace outlet oxygen content is decided by different fuel characteristic and load. When

oxygen content is at manual position, control it acc. to oxygen content control setting value.

If oxygen content control is automatic, through “automatic” or “manual” method

change oxygen content setting value to perform automatic control. When oxygen content

in flue gas is at “automatic” measure, acc. to the range in the following table to perform

adjustment.

Boiler load (T/H) 400 500 600 700 800 900 995

Flue gas oxygen content 6. 8 5. 5 4. 7 4. 35 4. 15 3. 95 3. 95




6.3.2.15 When oil burner is in service, burning oil fire condition should be monitored by flame

scanner. If there is not any oil burner, the corresponding pulverized coal feeder can’t be

put in service.

6.3.2.16 The best operation measure of pulverized coal feeder is that same burning tip is on two

arches to maintain the burning stability. In big load, try to put all pulverized coal feeder in

service and rotation speed should be controlled under 10rpm and can’t be more than

11rpm to prevent pulverized coal feeding pipe of rear wall blockage. When control

rotation speed pulverized coal feeder, the rate of increase or decrease should not be

large to reduce the interference of burning.

6.3.2.17 In operation, try to make rate of air /coal(PA/PC) meet the following requirement

Boiler load (%) BMCR 100%ECR 75ECR 50%ECR 40%ECR

PA/PC(air /coal) rate 1. 03 0. 98 0. 98 1. 17 1. 13




6.3.2.18 When do combustion adjustment or increase load of the boiler, besides keep steam

temperature and steam pressure normal, keep water wall outlet operating conditions

temperature in normal scope. After burners are put in service, immediately check

whether fire condition is good and immediately adjust air flow to prevent smoke emission

form the chimney.

6.3.2.19 In boiler normal operation, often check air leaking conditions of the body and duct. Check

seal of each section good, each valve and hole are closed strictly and ash handling

equipment seal good.

6.3.2.20 In boiler normal operation, operation conditions of burners and heating surface should be

checked. Strengthen analysis and comparison. If there is phenomenon of slag building,

clogging and fire extinction, immediately adopt adjustment measures.

6.3.3 Steam pressure control:

6.3.3.1 When unit are in the operation with “turbine and boiler coordinating” measure, through

inner control circuit, compare actual measured value of main steam pressure setting

value and actual measured value of boiler outlet main steam pressure to change boiler

load in order to let boiler combustion obtain adjustment and finally reach the objective of

controlling steam pressure to meet requirement of unit load.

6.3.3.2 In the period of starting-up the unit, minimum start-up pressure is controlled by HP

bypass at 60bar and unit is operated at “setting pressure” operation measure.

6.3.3.3 In the process of increasing unit load, gradually close HP bypass till it is completely closed.

HP bypass is changed to operation with “variety gradient” control measure. Unit control

measure is changed to “sliding pressure” operation.

6.3.3.4 Put boiler main load requirement and oxygen content control into “automatic”. The unit

gradually increase load through increasing steam pressure setting value.

6.3.3.5 When the following condition occurs, HP bypass shall be quick opened to control boiler

outlet pressure:

1) Turbine trips.

2) Operate with auxiliary power.

3) Main steam pressure is over 18. 5MPa.




6.3.3.6 Main steam pressure normal adjustment is controlled in±0. 2 MPa and not more than ±0.

5Mpa. If main steam pressure＞18MPa, it is regarded as “Main steam high pressure”.

6.3.4 Steam temperature control

6.3.4.1 In boiler normal operation, main steam temperature is controlled at 541±5℃, two side

differential temperature is lower than 10℃ and at the same time operation medium

temperature in each section and wall temperature doesn’t exceed regular.

6.3.4.2 Main steam temperature is controlled mainly by water spray attemperator. Superheater

primarily attemperator will perform “rough adjustment” for steam temperature and its

water spray volume is decided temperature before using attemperator. Keep wall

temperature of mid-temperature superheater from exceed the allowable value. By using

secondary attemperator of superheater performs “micro-adjust” to main steam

temperature to keep instability of boiler outlet steam temperature, high sensitivity of

controlling steam temperature by secondary water spray attemperator, and small delay.

Through changing flame center position, main steam temperature can be auxiliary

controlled.

6.3.4.3 Control of reheater steam temperature is mainly performed through combining

attemperating water and burning adjustment, i.e. through changing the position of

indicator of upper and lower third air control damper of front and rear arch to change

flame center position to reach the objective of decreasing or increasing reheat steam

temperature. Adopt water spray attemperating to control reheat steam temperature.

6.3.4.4 Use and attention for attemperating water :

1) Superheater, reheater water spray attemperating control can be used at

main steam flow＞150T/H. Superheater primary water sprays attemperating

is used

to control wall temp. of mid-temperature superheater, prevent over

limited and auxiliary control main steam temperature. Secondary

water spray primary attemperating is the final adjustment for the main steam

temperature. Differential temperature of two side of superheater should

not be more than 10℃ , Strictly control that attemperator outlet steam

temperature must be higher than saturated temperature 15℃ at its operation

pressure.

2) When control attemperating water and keep steam temperature,

adjustment of attemperating water can’t be quick increase or quick decrease

for the operation has a certain lag.

3) When control attemperating water, pay attention to differential pressure relation






between drum pressure and feedwater main pipe pressure. When feedwater

pressure is changed, attemperating water control valve should be

correspondingly adjusted. Usually keeping feedwater pipe pressure higher than

drum pressure 20 bar is better.

6.3.4.5 When the following condition occurs, especially pay attention to monitoring steam

temperature to prevent overheating and sharp drop of steam temperature.

1) Increase or decrease load

2) Start or stop burners

3) Start or stop Feedwater pump

4) Start or stop air fan (single side air fan trip or resume)

5) Start or stop pulverizing system

6) Start or stop high temperature heater

7) Instable steam pressure

8) Coal quality is changed.

9) Ash deposit, slag building on heating surface

10) Bad burning condition or changes of flame length

11) Pulverized coal is unbalanced. Pulverized coal fineness is changed

12) Soot blowing occurs.

13) Large fluctuation of drum water level

14) Boiler blowdown

15) When oxygen content in furnace is being changed.




6.3.4.6 In normal operation, each water spray attemperator shall be put in automatic service.

Pay attention to water spray automatic control in normal service. In changing operating

conditions, strengthen monitoring steam temperature to prevent over temperature. For

e.g. automatic control can’t follow the changes of steam temperature. Switch to “manual”

measure to adjust.

6.3.5 Drum water level control

6.3.5.1 Strictly monitor drum water level. Control variety rule of drum water level and feedwater

pump characteristic. Be familiar with equipment system and performance. In operation

keeping stable normal water level is the chiefly task to maintain boiler safety and

economical operation.

6.3.5.2 The change of water level shows the balance relation between boiler load and Feedwater.

When start the boiler and main pipe pressure of feedwater pump＞50 bar, open

feedwater pump outlet motorized valve. At this time put feedwater pump rotation speed

into “automatic”. On the control console send the opening order to feedwater control

isolation valve to automatically trigger the following procedure: For e.g. if feedwater low

flow control valve FCV52D is closed (ZSL52), open its isolation motorized valve UV20A,

UV20B (ZSH20A ZSH20B), put FCV52D into “automatic” operation. For e.g. If feedwater

main flow control valve FCV52 is closed (ZSL52), when Boiler main steam flow ≥380T/H

and send main flow control isolation valve UV19 opening order. Open FSRUV19 (ZSH19)

and feedwater control is switched from bypass control automatic to main flow control

valve FCV52. In boiler normal operation, through FCV52 control drum water level. When

load drop to flow≤286T/H or feedwater control valve front and rear differential pressure

(PT90-PT85=PPS90) ≥60bar, feedwater control is switched from feedwater control

automatic to bypass control valve FCV52D. Drum water level is controlled through

feedwater control valve and feedwater pump rotation speed. When only through

feedwater pump rotation speed controlling Drum water level, it will cause the fluctuation

of attemperating water pressure which makes steam temperature difficult to control.

Therefore, this measure can’t be adopted. When feedwater has to be controlled through

feedwater pump rotation speed, the staff should be more careful and pay attention to

change of attemperating water volume to prevent fluctuation of steam temperature.

6.3.5.3 Work scope of drum normal water level is -290mm－-175mm. When its water level drop

s to -240mm or rises to +100mm, low or high drum water level alarm is sent. When its

water level drops to -425mm, rise to +200mm, MFT trips.




6.3.5.4 In normal operation, put feedwater flow control into “automatic”, drum water level is set

“automatic” feedwater pump rotation speed and feedwater control valve is put at

“automatic” measure. And monitor drum water level in the following scope.

Boiler load (％) 50 60 70 800 90 100

Drum water level(mm) -290 -265 -245 -220 -200 -175

6.3.5.5 When boiler operating conditions is changed, e.g. When load, steam pressure, feedwater

pressure are changed, change of feedwater pump operation measure and change of

burning operating condition occur and boiler blowdown etc., strictly monitor change of

water level. If the fluctuation of water level is large, immediately switch water level control

to manual control to prevent the accidents caused by full water, inadequate water. If

emergency occurs, use continuous blowdown and intermittent blowdown valve to

cooperate with control.

6.3.5.6 When attemperating water flow is increased and water spray attemperating control valve

opening position is ≥70%, feedwater pump rotation speed should be automatic increased

and feedwater control valve should be automatic closed about 10%. (but not completely

closed). Keep feedwater main pipe pressure constant to avoid large fluctuation of drum

water level.

6.3.5.7 When drum water level automatic control jumps to “manual” measure, strengthen

monitoring and control of drum water level, feedwater flow and feedwater pressure.

6.3.5.8 If the following condition occurs, strengthen monitor and adjustment of water level :

1) The large fluctuation of feedwater pressure and feedwater flow.

2) When safety valve is opening or reseating and boiler blowdown.

3) When load is changed and HT heater exit operation.

4) When opening or closing feedwater pump, impulse starting, synchronization and

etc in the start-up or shut-down of boiler.

5) When feedwater pump and control equipment fault occurs.

6) When switch over control valve control and feedwater pump rotation

speed control or steam pump and motorized pump.

7) When pressure parts leaking occurs.




8) When open or close turbine control valve, bypass valve, superheater and main

steam pipe drain valve.

9) When burning is instable or perform fire extinction treatment.

6.3.5.9 Any data on drum remote water level indicator is abnormal, immediately contact with

thermal control staff to deal with If it can’t be resumed, and relieve water level protection.

6.3.6 Boiler blowdown

6.3.6.1 To keep steam, water quality and heating surface internal clean, must perform boiler

blowdown. Classify boiler blowdown to continuous blowdown and intermittent blowdown.

6.3.6.2 Continuous blowdown is controlled blowdown volume acc. to the result of chemical

analysis and boiler water quality parameter and through adjusting position of indicator of

continuous blowdown valve FSRUV17.

6.3.6.3 Intermittent blowdown is performed acc. to the result of chemical analysis and after

receiving the notice from chemical shift supervisor, through intermittent blowdown valve

FSRUV02 or 2 mins blowdown at morning shift every day. Intermittent blowdown shall be

performed at low load

6.3.6.4 Intermittent blowdown operation

1） Check closure valve FSRHV034 at Open condition, micro-open

intermittent blowdown valve FSRUV02 to heat pipe.

2） After heating pipe, fully open intermittent blowdown valve FSRUV02, after 2min,

close this valve.

3） In the process of intermittent blowdown, pay attention to the change of drum

water level and operation conditions of boiler water circulation pump to prevent

water circulation from damaged.

4） If blowdown is finished, blowdown valve FSRUV02 should be checked

closed strictly.

6.3.6.5 If the following condition occurs, stop intermittent blowdown operation :

1) When drum water level is not normal, feedwater control is no good.

2) Blowdown system fault or strong vibration of pipe.

3) Boiler accidents occurs.




6.3.6.6 Prohibit long period blowdown and blowdown valve leaking. In operation to prohibit boiler

blowdown by boiler water circulation pump inlet header drain valve.

6.4 Boiler operation measure control

6.4.1 Totally there are 5 types of units’ operation measures: manual, Boiler following mode,

turbine following mode and coordinate control and electricity network control.

6.4.2 Manual measure: it is the most basic measure, boiler main controller and turbine main

controller operation measure is at manual measure, i.e. Boiler side, turbine side is manually

kept parameter by operation staff and change unit load or keep stable operation acc. to

requirement.

6.4.3 Boiler following mode: Turbine controls load, Boiler controls inlet pressure. At this time,

turbine main controller is at manual measure, or remote control of DEH system not put in

service. At this measure, turbine controls load, and boiler main controller in automatic measure

operation, automatic closed loop control inlet pressure.

6.4.4 Turbine following mode: Boiler controls load, Turbine controls inlet pressure. At this time,

boiler main controller is at manual measure, but turbine main controller is in automatic measure

operation. Through changing position of indicator of control valve to stable inlet pressure, at

this measured DEH systems put in service.

6.4.5 Coordinate control measure: at this measure, boiler main controller and turbine main

controller is in automatic measure operation.

6.4.6 Electricity network control: at this measure, unit coordinate control is put in service, and

electricity network load dispatch system put in automatic following. Electricity network send

Generator unit load order, Generator unit automatic follows load order and boiler and turbine

make corresponding automatic control to meet requirement of electricity network load order.

7 Shut-down of Boiler

7.1 basic regular (generals )

7.1.1 Boiler normal shut-down must strictly be accordance with shut-down curve control relevant

parameter.

7.1.2 In boiler abnormal shut-down must prevent shut-down in the process of accidents or

enlargement accidents.

7.1.3 Before shut-down of boiler do corresponding check and preparation.

7.1.4 After shut-down of boiler, if emergent repair is needed, accelerate boiler cooling i.e.

compulsory cooling and adopt the following operation:




7.1.4.1 Keep Drum high water level+300～+500mm, and strengthen changing water, deaerator

water temp. is decided by boiler cooling condition.

7.1.4.2 After shut-down for 6 hour, Boiler is sealed. After shut-down for 6～18hour, Boiler

naturally air draft.

7.1.4.3 At 18 hour after shut-down, open 1 ID, FD Fan, keep about 30％BMCR air flow Boiler to

compulsory air draft.

7.1.4.4 Strictly control Pressure Drop speed, total temperature drop and pressure Drop In the

process of drum upper, lower wall differential temperature≤40℃.

7.1.4.5 Strictly monitor boiler water circulation pump operation conditions, when Drum pressure

＜15bar, close 1 boiler water circulation pump. If boiler water circulation pump has

vaporization Phenomenon, immediately stop boiler water circulation pump operation.

7.1.4.6 When boiler water temperature＜70℃, close boiler water circulation pump, Boiler drain.

7.1.5 After shut-down, in order to prevent heating surface from internal erosion, per different

conditions, perform corresponding shut-down maintenance work.

7.1.6 When boiler pressure doesn’t drop to 0 and Motor power isn’t cut off, giving up monitoring

boiler unit and auxiliary equipment can be allowed.

7.1.7 In the process of shut-down strictly control Pressure Drop speed, seriously operation, and

strictly monitor differential temperature of drum upper, lower wall is less than 40℃.

7.2 Preparation before shut-down of boiler

7.2.1 The shut-down of Boiler unit must obtain the superior order, and the measure, reason and

period of shut-down and then prepare for the shut-down, and inform chemical, burning

operation, desulphurization staff on duty and Thermal control staff of shut-down period.

7.2.2 Before shut-down, inform each staff on duty to comprehensively check system managed

by himself to record all detailed defects condition to solve all the defects after shut-down.

7.2.3 If the period for shut-down is more than 3 days, grind all the coal in the bunker grinding.

Pulverized coal in pulverized coal bunker need be burned out. If the period for shut-down is in 3

days, the position of pulverized coal shall be less than 5 meter.

7.2.4 Comprehensively check Burning oil and Atomization steam system has been put in

stand-by. Atomization steam pressure is normal; each oil burner is reliable which can be put in

service at any time.

7.2.5 Decrease load before shut-down, soot blow boiler body and air preheater.




7.2.6 Comprehensively check HP bypass system, confirm Hydraulic plant operation normal.

7.3 Shut-down with sliding parameter (need cooling )

7.3.1 Shut-down adopts sliding parameter shut-down; gradually reduce the boiler combustion

with turbine decreasing load to keep steam pressure, temperature and flow suitable for the

requirement for turbine sliding parameter decreasing load.

7.3.2 When decrease fuel, decrease corresponding air flow. Strictly prohibit total air flow ＜

30%MCR till the unit are shut-up.

7.3.3 When pulverizing system thoroughly pumped, stop pulverizing system and keeps

lubrication system of tube mill long operation.

7.3.4 Close moisture absorption valve at pulverized coal bunker.

7.3.5 At 75% of boiler load (Steam flow 750t/h) stop PC burners as required and keep the

associated fuel oil burner in service, continue decreasing load and monitor furnace

temperature.

7.3.6 Switch from “global flame detection” mode to “individual scanning” mode occurs when the

boiler load is below 70% BMCR (618t/h). Stop PC burners as required and keep the associated

fuel oil burner in service (at least until the PC pipes have been purged).And from then on the

measure is mixture of oil and pulverized coal. Put A. P soot blower, keep continuous soot

blowing pattern.

7.3.7 With drop of unit load, slowly decrease main steam pressure setting value, monitor

superheat steam temperature and Reheat steam temperature drop rate should be ＜1℃/min.,

In the process of whole pressure drop, Drum upper and lower wall differential temperature

should be lower than 40℃.

7.3.8 When automatic control is not good, switch to manual adjustment.

7.3.9 Gradually close pulverized coal feeder. Firstly close pulverized coal downcoming gate of

pulverized coal feeder .When pulverized coal is empty, close pulverized coal feeder.

7.3.10 When Boiler Main steam flow≤286T/Hour feedwater control valve front and rear differential

pressure≥60bar, feedwater control is switched form feedwater automatic control to bypass

control.

7.3.11 When Main steam flow＜250T/H, all pulverized coal feeder is stopped unconditional.

Inform of stopping ash handling, keep cathode and anode rapping in operation and ash

handling equipment in operation.




7.3.12 When Main steam flow＜150T, stop using attemperating water . When water spray

motorized valve and control valve can’t be closed tightly, stop each water spray manual valve,

and make operation record.

7.3.13 When the load is 75MW, switch to auxiliary power. When load is 50MW, switch valve of

turbine, quick decrease load to 0. Generator reverse Power trip, perform shunt tripping of

turbine. Shut-down the boiler and close all burners. Purge all PC pipes correctly. Close burning

oil safety valve and each oil burner input oil manual valve and burning oil control plant inlet oil

manual main valve. Confirm all fuel is cut off.

7.3.14 To prevent Atomization steam from entering into furnace in the period of shut-down of

boiler, close atomization steam main valve.

7.3.15 After boiler trips, close the superheater stop valve FSR UV 004 and the HP by-pass.

Open rear pass drain FSR UV 003, 005. Open the drains and blow down devices of the main

steam piping and main turbine piping, according to the instructions of the turbine manufacturer.

7.3.16 Do not reduce airflow below 30 % of full load airflow. keep total air flow 30%MCR, after

performing furnace purge for 10 mins, gradually stop Primary air fan, FD Fan, ID Fan, confirm

each air fan Inlet and outlet damper closed.

7.3.17 Trip A, B side Steam air preheater

7.3.18 Contact with chemical staff on duty, stop chemical feed pump, and close chemical feed

valve, continuous blowdown valve and ach sampling valve.

7.3.19 Keep 2 Air Preheaters operation, 1 flame scanner cooling air fan in operation, 1 oil burner

cooling air fan operation.

7.3.20 Keep 2 boiler water circulation pump in operation, When drum pressure＜15bar, per the

conditions stop 1 boiler water circulation pump operation. Keep drum high water level +100mm.

Open Economizer recirculation valve.

7.3.21 Control boiler cooling rotation and keep the differential temperature measured by any two

thermal couple is less than 50 °C.

7.3.22 When Drum pressure≤3bar, Open each Air damper of superheater and reheater.

7.3.23 To prevent economizer, air preheater and etc. from secondary burning which damages

equipment. After shut-down boiler, monitor gas temperature of each section. When air

preheater inlet gas temperature ＜120℃, stop A, B air preheater operation, stop flame scanner

air fan and oil burner cooling air fan operation.




7.3.24 When boiler water temperature≤70℃, stop boiler water circulation pump. Close outlet

non-return flap and heating pump manual valve, power of 3 boiler water circulation pump

should be cut off. Open Drum left, right side interlayer of air damper.

7.3.25 When boiler water temp.≤70℃ and boiler water circulation pump is stopped, if boiler must

be drained, comprehensively check the steam and water system.

7.4 Normal shut-down (hot stand-by )

7.4.1 When shut-down, try to keep main steam pressure and Main steam temperature.

7.4.2 Speed of pressure drop when load is dropped is much lower than cooling speed of normal

shut-down.

7.4.3 Put soot blowing equipment in service for A.P.

7.4.4 When the turbine is off load, the boiler should continue to be fired in order to increase the

pressure above 140 bar before bottling (Per the conditions of hot stand-by equipment).

7.4.5 After boiler fire-off, close main steam valve and HP bypass valve, close all air valve

damper to bottle-up.

7.4.6 Operation of shutting-down each valve of steam, water system for hot stand-by is as

following:

7.4.7 Open Reheater outlet steam exhaust valve, FSRUV001.

7.4.7.1 Open cold Reheater main pipe drain valve FRSUV002.

7.4.7.2 Keep all drain valve and Air damper of drum, Superheater and Reheater closed.

7.4.8 Keep total air flow 30%MCR, after performing furnace purge for 10 mins, stop Primary air

fan, ID Fan, FD Fan.

7.4.9 Steam air preheater trip.

7.4.10 Keep Drum high water level+100mm, completely close Feedwater motorized valve.

7.4.11 If hot stand-by period, keep 2 Air Preheater, 1 flame scanner cooling air fan, 1 oil burner

cooling air fan, 2 boiler water circulation pump operation.

7.4.12 Keep lubrication system of tube mill long operation.

7.4.13 After shut-down for 20 hour, open the following drain valve to drain 1 hour for superheater

system. Keep Air damper of Drum and superheater closed.

7.4.13.1 Open front wall enclosure drain valve FSR UV003

7.4.14 Open rear wall enclosure drain valve FSR UV005




7.4.14.1 Open Main steam valve front drain valve FSR UV006

7.5 Emergency shut-down

7.5.1 Emergency shut-down is quick shut-down to prevent from serious accidents or enlarging

accidents needed when serious faults of boiler or other main equipment occur.

7.5.2 Emergency adopts the MFT order which will cut off immediately all the fuels to the boiler

furnace (coal and fuel oil).

7.5.3 The sequent operation follows the operation after the boiler fire-off in hot stand-by

shut-down terms

7.6 Shut-down maintenance

7.6.1 Maintenance in short shut-down of boiler (shut-down 3~4 days) :

7.6.1.1 Maintenance in short shut-down of boiler (shut-down 3~4 days), for hot stand-by, Boiler

can be started arbitrarily.

7.6.1.2 Treatment after shut-down refer to “Boiler normal shut-down (hot stand-by)”.

7.6.2 Maintenance in medium-period shut-down of boiler (shut-down 3~4 weeks) :

7.6.2.1 After Boiler fire-off, immediately sub-control closing boiler main steam valve FSRUV04A,

FSRUV04B. When shaft seal of turbine don't use steam, immediately close HP bypass.

7.6.2.2 Open reheater outlet steam exhaust valve FRSUV001, High temp. Reheater inlet, outlet

Air damper: FRSHV006, HV007, HV014, HV008, HV009, and cold reheater main pipe

drain valve FRSUV002.

7.6.2.3 Open Superheater drain valve: Open front wall enclosure drain valve FSRHV019, UV003.

Open rear wall enclosure drain valve FSRHV020, UV005.Open main steam valve front

drain valve FSRHV068, UV005.

7.6.2.4 Close continuous blowdown valve, each sampling valve, chemical feeding valve

7.6.2.5 When Drum pressure≤3bar, open superheater air damper, When Air damper doest

overflow steam, immediately close Air damper, drain is finished, close Each drain valve,

and completely isolate hot seam pipe and of the atmosphere.

7.6.2.6 When reheater drain is finished, close reheater outlet atmospheric relief valve. Each Air

damper of high temperature reheater inlet and outlet, and cold reheater main pipe drain

valve completely isolate reheater steam pipe and the atmosphere.




7.6.2.7 When boiler water temperature drops below 180℃ and drum water level is at about

-290mm, inform chemical staff of adding N2H4 and NH3, keep boiler water circulation

pump operation to keep N2H4＝200ppm, PH≥10. 5. in boiler water and keep drum water

level+100mm.

7.6.2.8 When boiler water N2H4＜50ppm, immediately add N2H4.

7.6.2.9 When boiler water temperature≤120℃, boiler water circulation pump can be stopped.

7.6.2.10 Superheater system filling N process:

1） When Superheater drain is finished, Boiler pressure drops to

1bar, open superheater filling N valve FSRHV031, and HV029, Open drum inner

layer filling

N valve FSRHV007, and HV005. Notice, must fill N in the boiler cooling process.

In the process of filling N keep Nitrogen pressure in the scope of 0. 1~0. 3bar to

prevent air entering in to furnace.

2） When boiler water circulation pump is stopped, Open drum inter layer filling N

valve :FSRHV045 and HV044to fill N to the furnace, and keep Nitrogen pressure

0. 1～0. 3bar.

7.6.2.11 Filling N Process of reheater system:

1） Check before reheater system filling N

2） In the cooling process of Boiler

3） Close HP bypass valve

4） Each valve of reheater water spray attemperating system closed tightly

5） LP bypass valve close

6） Close turbine HP cylinder steam exhaust non-return flap, Medium

pressure cylinder steam intake valve, and high #section air pump

valve and isolation primary damper on pipe.

7） After cold Reheater main pipe drain is finished, close drain valve.






7.6.2.12 After reheater air exhaust is finished, close reheater outlet atmospheric relief valve and

air damper at high temperature reheater inlet and outlet.

7.6.2.13 Open reheater filling N valve FRSHV012 and HV006, HV014 to fill reheater system N,

keep Nitrogen pressure 0. 1~0. 3 bar, to prevent air entering in to reheater system.

7.6.3 Maintenance for boiler long shut-down(shut-down 4weeks~3 months):(wet)

7.6.3.1 Maintenance pricinple:

1） Under normal conditions, after shut-down of boiler perform wet

maintenance for superheater system. Only the major or minor repair and repair

on pressure parts occur, dry maintenance (hot boiler drain) shall be performed.

2） When unit are shut-down for more than 2 weeks, change from feedwater

pressure maintenance or dry maintenance (hot boiler drain) to

ammonia -hydrazine maintenance for superheater.

3） Reheater adopts filling N maintenance.

7.6.3.2 Maintenance method key points:

Drain the remaining left water in Boiler. Fill the boiler superheater with ammonia

-hydrazine solution maintenance liquid. Prevent Air from entering. Perform filling N

maintenance for reheater.

7.6.3.3 Superheater system maintenance operation method :

1） At cold status of boiler, open air damper, drain valve and water discharge valve

of steam, water system. Drain the remaining water in feedwater system, water

wall and superheater. When the remaining water in feedwater system, water wall

and superheater is drained,(about 2hour ),close all drain manual or motorized

valve and water discharge valve and intermittent blowdown manual valve and

continuous blowdown manual valve (Open when perform chemical sampling)

2） Chemical staff maintenance makes the maintenance solution

maintenance chemicals box, When water level of feedwater box is highest

after level which can be seen (2800mm). Open pump feed feedwater

with chemical (chemical feed is switched to feedwater box)

3） After receiving the notice that chemical staff finishes feeding chemicals,

open feedwater pump to circulation feed water 30 min, mix the chemicals and

liquid.






4） Chemical make the sampling analysis of feedwater that the concentration of

maintenance liquid:N2H4≥200mg/l,PH 10~10. 5.

5） Open condensate water pump to fill water to boiler water circulation pump motor.

6） When filling water for boiler water circulation pump motor is

finished, open feedwater pump, make use of feedwater bypass to fill boiler to

+100mm, run 3 boiler water circulation pump for 3 times, put #2boiler water

circulation pump in service. At this time, stop filling water for boiler water

circulation pump and stop filling Boiler.

7） Make use of superheater secondary attemperator water

system to fill superheater acceptable maintenance solution, system top

pressure, When Drum pressure reach 0. 3Mpa, close all air damper, boiler filling

is finished.

8） Inform of chemical boiler water sampling analysis, water quality standard is: PH

10~10. 5, N2H4 50~200mg/l.

9） In the period of maintenance, when Drum water level drop to

high water level+500mm, open 1 feedwater pump. Through

superheater secondary attemperator fill water to boiler, top pressure. When

drum pressure reach 1 bar, stop fill water to boiler.

10） When maintenance solution in feedwater box is not enough, inform chemical

staff of making chemical, feed chemicals feed and water feedwater box.

7.6.3.4 Perform filling N maintenance of reheater system, Nitrogen pressure is kept at 0. 3~0. 5

bar and method is as following:

1） Check before reheater system filling N :

a） Boiler has been cooled.

b） HP, LP bypass has been closed.

c） Motorized valve, control valve and manual valve of reheater A,

B side attemperating water have been closed.

d） Close turbine HP cylinder vent non-return flap and bypass

motorized valve ,mid pressure cylinder steam intake valve ,high temperature

heater #7 section steam pump motorized valve and drain manual valve

(AHP HV087), motorized valve at cold reheater to deaerator and

motorized valve at cold






reheater to auxiliary steam header,

e） Open cold, hot reheater main pipe drain motorized valve (for steam exhaust).

f） Atmospheric relief valve at reheater outlet is closed.

g） Each Nitrogen bottle at Nitrogen station is full filled with nitrogen.

h） Safety valve at Nitrogen station air supply main pipe has been

checked acceptable.

2） Filling N operation :

a） Micro-open air supply valve at each Nitrogen bottle of Nitrogen station.

When the pressure before opening pressure governor valve at air supply

main pipe reach 120bar~150bar, stop opening Nitrogen bottle.

b） Manually control pressure governor valve at Nitrogen station. Keep

Nitrogen pressure after opening pressure governor valve at 5 bar. Fill Nitrogen

pressure governor station with Nitrogen to exhaust air.

c） Close front ,rear manual valve pressure governor valve at pressure governor

station.

d） Manually open pressure governor station bypass manual valve

and make valve outlet Nitrogen pressure 2 bar and reheater system filled

N to exhaust air.

e） After 60min, manual close pressure governor station bypass manual valve.

Reheater system filling N to exhaust air is finished.

f） Manually close bypass manual valve of pressure regulation station and

close drain motorized valve of cold reheater and hot reheater

main pipe. Purge reheater system and exhausting air is finished.

g） Open reheater system filling N valve FRS HV012, FRS HV006, FRS HV014.

h） Open front ,rear manual valve pressure governor valve at pressure

governor station, manually clockwise control pressure governor valve to make

pressure after opening pressure governor valve 0. 3 bar～0. 5bar.

i） Reheater system filling N is finished. Record Nitrogen pressure of

Nitrogen station and Nitrogen pressure governor station






7.6.3.5 Monitoring in the period of maintenance:

1） Each shift record boiler drum pressure, reheater Nitrogen pressure twice.

2） Every Monday separately open each boiler water circulation pump

once and each time is 30min. If circulation is finished, inform chemical staff

of sampling and analyze concentration of maintenance solution.

3） In the period of maintenance, boiler water, open feedwater box sampling valve,

and keep flow of 50~200ml/h.

7.6.4 Boiler heating with pressure drain maintenance method:( suitable for mid, long period

shut-down )

7.6.4.1 When in the mid or long period of boiler shut-up boiler or after shut-up, pressure parts

need long repair time and can’t be performed wet measure. And when perform filling N

maintenance, boiler can adopt heating boiler with pressure and drain. When Boiler water

is drained out, make use of boiler remaining heat to dry instrument of pressure parts in

boiler to reach the objective of maintenance.

7.6.4.2 Operation steps

After boiler shut-down, when drum pressure is 10bar:

1） Stop boiler water circulation pump, inform electric staff cut off power.

2） Close boiler water circulation pump outlet valve and boiler water

circulation pump is at isolation condition.

3） Open HP side air exhaust damper of boiler water circulation pump cooler.

4） Boiler drains. Each valve position in the system is listed in the following table :

No. Valve Name Valve No Status

FSR HV032 open

1

Economizer drain valve

FSR HV033 open

2

Continuous blowdown valve

FSR HV081

HV082

UV17

close

close

close

3

Drain valve at boiler water circulation

FSR HV012 open




pump Inlet header FSR HV060 open

FSR HV049 HV080 HV062 open

4

Water wall circumferential

header drain valve FSR HV071 HV084 open

FSR HV034 open

5

Intermittent blowdown valve

FSR UV002 open

FSR HV068 open

6

Main steam valve inlet drain valve

FSR UV06 open

5） If drain is finished, close all drain valve in above table.

6） When Drum pressure reach 3bar, open the following Each valve :

1 Economizer outlet air exhaust valve FSR HV074 HV073 HV075 open

2 Drum inner-layer air damper FSR HV005 HV006 HV008 HV009 open

Drum interlayer air damper FSRHV044 HV046 open

3

Drum interlayer air damper FSR SV40 HV047 open

4 Top outlet header air damper FSR HV063 HV064 open

5

Low temp. superheater outlet

air damper

FSR HV021 HV022

open

6

Mid temp. superheatier outlet header

air damper

FSRHV054 HV055 HV056

open

7

High temp. superheater outlet header

air damper

FSR HV029 HV030

open

8 High temp. reheater Inlet air damper FSRHV014 HV006 HV007 open

9 Reheater outlet steam exhaust valve FSRHV013 UV001 open

7） When Boiler drain is finished for 2hour, Open each drain valve of steam side:

No. Valve Name Valve No Status




1 Drain valve at roof Inlet header FSRHV050 HV059 open

2 Front wall enclosure drain valve FSRHV019 UV003 open

3 Rear wall enclosure drain valve FSRHV020 UV005 open

4

Drain valve from low temp.

superheater to medium temp.

superheater

FSRHV023 HV024 HV035

open

5 Main steam valve front drain valve FSRHV068 UV006 open

6 Low temp. reheater Inlet drain valve FSRHV015 UV002 open

a) When above air damper and drain valve is opened for 2hour, close all air damper

and drain valve.




7.6.5 Points for attention of Boiler maintenance:

7.6.5.1 In the period of boiler maintenance, chemical staff shall assay boiler water quality acc. to

regular, when N2H4 concentration ＜50ppm, it should be added to original content.

7.6.5.2 Before boiler is added hydrazine and ammonia (i.e. N2H4 and NH3), only keep 1 boiler

water circulation pump in operation, other outlet of 2 boiler water circulation pump shall

be closed.

7.6.5.3 Before boiler is filled N after cooling.

7.6.5.4 After filling N maintenance, if entering in to drum to work is needed, perform air draft and

then can enter into it.

7.6.5.5 Boiler adopts maintenance of adding Na3PO4. 12H2O(Na3P04)solution, before open

boiler, must perform drain and rinsing work. Its drain method is as same as shut-down

drain method.

8 Boiler auxiliary equipment

8.1 Basic regular of auxiliary equipment operation

8.1.1 Check before auxiliary equipment is put in service:

8.1.1.1 Check work-sheet is finished, no staff works on the equipment.

8.1.1.2 Full of light on site, clean ground, no debris obstructing operation.

8.1.1.3 Equipment Appearance is in its integrity with heat good insulation. Each hole valve is

strictly closed, connection with the system completely. Instrument is complete and

direction is right.

8.1.1.4 Bearing Lubrication position is normal, oil quality is acceptable, and Lubrication system

at good stand-by status. Grease is added per the regular.

8.1.1.5 Cooling water unobstructed, water flow is adequate and don't overflow.

8.1.1.6 The Anchor Bolt is complete and firm. Motor wiring and earthling cable is good. Insulation

is acceptable.

8.1.1.7 Shields are complete and integrated.

8.1.1.8 The data on DCS of each air valve is consistent with the actual and transmission

machine is complete.

8.1.1.9 Control circuit power, interlock, thermal control staff protection test is acceptable and is in

service, automatic equipment is put in service or has the start condition.




8.1.2 Auxiliary equipment open principle:

8.1.2.1 Normal open 6KV equipment and 380V equipment. Specified staff stands at the position

of accidents button to monitor it on site. If any problem is found, immediately put accident

button stop operation.

8.1.2.2 The equipments with the same trunk can’t be operated at the same time before opening

2,6 KV equipment inform the electric operation staff. Without permission, it can’t be

opened.

8.1.2.3 In normal condition, squirrel-cage Motor at cold status can be allowed opened twice.

Each interval will not be lower than 5min. At hot status can be allowed opened only once.

Only when there is accident treatment and opening time is not more than 2～3 mins,

motor can be opened once more. Otherwise, it can be opened after 30min (iron core

temperature is hot status when it is above 50℃, below 50℃ it is cold status).

8.1.2.4 Strictly prohibit opening with load.

8.1.2.5 When open auxiliary equipment pay attention to it’s the executing condition of opening

procedure, current returning time, current indicator and other Parameter of equipment.

Pay attention to the display on monitor CRT equipment status is correct.

8.1.2.6 After open equipment local check equipment in good operation, without any abnormal

sound, vibration,, friction and percussive sounds.

8.1.3 General rule for Auxiliary equipment operation maintenance:

8.1.3.1 Cooling water is adequate and lubricating system is normal.

8.1.3.2 Equipment operation is stable without any abnormal noise and abnormal friction and

impact sound. Each parts and inlet or outlet pipes are complete and not loose, non-swing

and etc.

8.1.3.3 Operation of Each valve, air valve and primary dampers flexible, action is normal and

position direction is correct.

8.1.3.4 Each thermodynamic, electric instrument for measure and display is normal.

Thermodynamic, electric protection and relevant automatic control is put in service and is

normal.

8.1.3.5 Control the following parameters according to manufacturer’s requirement. If there is no

requirement, control according to the following requirement:

1） Rolling bearing temperature≯80℃,sliding bearing temperature℃≯65.




2） The shell temp. of gear gearbox ≯60℃.

3） Opening Motor shell temperature≯65℃,enclosed motor shell ≯humidity 80℃.

4） Rolling equipment axial shaft displacement is ≯2~4mm. Sliding equipment axial

shaft displacement is ≯0. 5mm:

5） Vibration value:

Rotation

speed(r/min)

≤3000

≤1500

≤1000

≤750

Vibration

value(mm)

0. 05

0. 085

0. 10

0. 12

6） When any of the following conditions occurs, emergently stop auxiliary equipment

operation :

a） Bearing temperature abnormal rises or exceeds the regular.

b） When strong vibration on the equipment or axial shaft displacement

or the danger which may damage equipment occurs.

c） Motor or cable smokes and fires.

d） The obvious sound of metal friction in the inner of equipment can be clearly

heard.

e） Other faults which endangers safety of person and equipment.

8.1.4 General rules for rotation equipment fault and treatment

8.1.4.1 When any of the following conditions occurs, emergently stop operation of rotation

equipment :

1） Equipment has strong vibration.

2） The obvious sound of metal friction in the inner of equipment can be clearly heard.

3） Motor or cable smokes and fires.

4） Bearing smokes and fires or sliding bearing temperature exceeds 80℃,

rolling bearing temperature exceeds 100℃.

5） Equipment leaking endangers safety of person and equipment.




8.1.4.2 When any of the following conditions occurs, firstly open stand-by pump (air fan ),stop

fault pump (air fan ):

1） Gland heats, smokes or with overflowing water, oil leaking, and adjustment is not

efficient.

2） Sliding bearing temperature reaches 65℃,rolling bearing temperature reaches 80

℃ and with rising trend.

3） Motor shell temperature rises to 70℃,and continues rising.

4） Motor Current exceeds rating value.

5） Motor cable is serious overheating. The insulation exude a smell of burning

8.1.4.3 Treatment for operation pump (air fan) trip:

1） Confirm operation pump (air fan) trip and stand-by pump (air fan ) shunt good.

Reset gang pump (air fan )switch. If stand-by pump (air fan )is not gang ,manual

open it.

2） Cut off trip pump (air fan )operation switch.

3） check each section of gang pump (air fan ) normal, check the reason for trip of trip

pump (air fan )and solve it for stand-by.

4） If opening stand-by pump (air fan )don’t take effect, immediately check for the

cause. For the 380V motor ,start trip pump (air fan )again once more . Confirm

6KV power equipment should be checked no obvious fault ,it can be switched on

again.




8.1.4.4 For important plant service auxiliary equipment, besides the faults which endangers

safety of person and equipment must be immediately stopped. Usually open the stand-by

auxiliary equipment and then stop fault auxiliary equipment.

8.2 Motor operation

8.2.1 Motor can be operated at the temperature of rated cooling air according to the specified

data on manufacturer’s name plate.

8.2.2 The highest monitoring temperature of motor coil and iron core shall not be exceeded

in any case according to manufacturer’s regulation. If manufacturer has no regulation, the

highest temperature of the motor coil and iron core can’t exceed 105℃ and the rise of

temperature can’t exceeds 65℃.

8.2.3 Motor can be operated in the scope of 95%~110% of rated voltage, and its rated output is

constant(5. 7～6. 6 KV, 360～420V). In the period of rated output operation the unbalanced

value of voltage between phases can’t exceeds 5％. In the period of operation at unbalanced

voltage pay attention to over-hot and vibration of the motor.

8.2.4 In normal operation , motor current shall not exceed ＋5％ of rated value. If it exceeds ＋

5％ to ＋10％ , in 15 min shift supervisor can’t decrease the current to rated current. If it is

caused by the accidents of main motor, the above rule needn’t to be followed.

8.2.5 Temperature of motor bearing is controlled according to the following standard (If the

manufacturer has its own requirement, perform according to manufacturer’s regulation):

8.2.5.1 Sliding bearing :can’t exceeds 80℃(Temperature rises by 40℃).

8.2.5.2 Rolling bearing :can’t exceeds 100℃(Temperature rises by 60℃).

8.2.6 Daily check work, maintenance for motor and the detailed requirement of opening and

stopping operation refer to specific terms in “electric operation manual.

8.3 Start-up, stop and operational maintenance of auxiliary equipment and system

8.3.1 High voltage bypass

8.3.1.1 Check-up before the start-up of high voltage bypass.

1) Make sure that every pipeline is perfectly connected with facilities, valves complete, and

test and adjustment fully completed and that movement is flexible and reliable as well.

2) Make sure that the functioning of the hydraulic pressure station is

normal without leakage.

3) Thermal meter and controlling system should be put into use




4) Open the hand-operated valve of attemperating water HV002.

8.3.1.2 Start-up of high voltage bypass

1) Make sure that the hydraulic pressure station is normally functioning.

2) Put into use the high voltage bypass on DCS.

3) Turn on the pressure-reducing valve controller of the high voltage bypass to

20% by hand.

4) Set main steam pressure and steam pressure lower limit (the stream pressure is set at 60

bar).

5) Set steam temperature of the high voltage bypass outlet at 320℃, press the “automatic”

button on the attemperating water regulating valve controller of high voltage bypass.

6) Send out the start-up order, the “red” indicator light at the HSN001 operation station will

soon be “brightened”.

7) Operate automatic on the pressure-reducing valve of the high voltage bypass, the high

voltage bypass thus enters into operation with a minimum opening of 40%

and “the minimum opening” indicator light is on.

8) When the steam pressure of the boiler outlet is below the minimum fixed value (60bar) on

starting up, set the regulating valve of the high voltage at start-up opening fixed value

(40%).

9) When steam pressure reaches the minimum start-up pressure (60 bar), the “minimum

opening” indicator light is off, while “the minimum pressure” indicator light is on, ensuring

the high voltage bypass is controlled in a state of minimum pressure.

10) Maintain the minimum pressure of start-up when the pressure-reducing valve of the high

voltage bypass gradually opens as the burning is intensified.

11) When the “high-pressure cylinder” switch signal has been sent out,

the “minimum pressure” indicator light is off, while “slip pressure” indicator is on,

bringing the system into an operational state.

12) Close the high voltage valve as turbine valve gradually opens to maintain

the fixed pressure values, and during this process, the PI controller will set the changing

gradients

at the fixed value of 4 bar/min.




13) As the turbine load increases, the high voltage valve will be narrowed till it is fully closed

when the “slip pressure” indicator light is off while the “normal functioning” indicator light

is on

14) After that, the high voltage pressure-reducing valve will automatically regulate

rate of pressure rise of the boiler.

8.3.1.3 Functional maintenance and parameter

1) High voltage bypass parameters

Items Unit Data

Steam temperature of

the high voltage bypass inlet

℃

540+5

Pressure of the high voltage

bypass inlet

bar

184

Pressure of the high voltage

bypass outlet

bar

44

Steam temperature of

the high voltage bypass

outlet

℃

337+5(>360℃alarming)

Flow of high voltage bypass T/H 760

Pressure of

attemperating water

bar

210

Temperature of

attemperating water

℃

257

The start-up controlling time

of the high voltage bypass

S

12

Swift-opening time of

the high voltage bypass

S

3

Opening time of

attemperating water stop

valve

S

3




Full-opening time of

attemperating water S 8

regulating valve

2) Conditions for swift opening of pressure reducing valve of the system

a) Reach safety ∆P (adjust safety valve to influence load)

b) Reach Pmax safety (adjust safety valve)

c) When turbine is running (high voltage main body of turbine opens), auxiliary power

operates, or else steam turbine will trip, forecasting the full close

down of high voltage main body.

d) Operator can open it by hand (press any button), and under any circumstances, it

can be swifted from the manual-controlled model to the automatic model when the

high voltage valve is opened. It is also suitable for desuperheat-regulating ductwork.

8.3.1.4 Operation of high voltage bypass in the stoppage process of the unit

1) When the set pauses in the phase of “slide pressure”, lower the main steam pressure

setting and ensure high voltage maintains “set” pressure for regulating.

2) When the set enters into the phase of “fixing pressure to reduce load”, as the regulating

valve of the steam machine gradually narrows, the pressure-reducing valve is opened,

maintaining the fixed pressure.

3) Hydraulic pressure station keeps on operating after the boiler stops working to ensure

that the pressure-reducing valve remains in a closed state.

8.3.1.5 Faults and countermeasures of high voltage bypass

1) Causes:

a) Failure of hydraulic pressure station

b) Failure of 380V power supply and tripping of hydraulic pressure oil pump

c) Failure of 48V DC power

2) State

Automatic closing and locking of FCV58, UV59 and TCV59

3) Countermeasures




Find out the causes and have faults removed immediately

8.3.2 Air preheater

8.3.2.1 Check-up before the start-up of air preheater

1) Make sure that there are no people working and no foreign bodies in the air preheaterhas

no, and that man holes are fully closed when the maintenance of work ticket is finished,

and that the surrounding of the air preheater has no sundries.

2) Make sure that the smoke and air flues are well connected and that the

executive mechanism of sealing device is in a high position.

3) Make sure that executive mechanisms UV03 and UV04 have sent off electricity.

4) Make sure that the speed reducer has been injected with qualified oil, and that hydraulic

couplers has also been oiled without leakage.

5) Make sure that soot-blower is placed in the outlet and that the soot-blowing and steam

pipelines are connected.

6) Make sure that smoke, air pressure, and temperature and fire-measuring devices and

local control switch as well, are in good condition.

7) Fire protection and check-up of cleaning system:

a) Make sure that pipes are fully connected and equipment complete.

b) Close fire protection and fire-extinguishing nozzle manual valveHV001 and HV007,

close fire-fighting water-cleaning manual inlet valveHV002 and cleaner manual valve

as well.

c) Open fire protection hose leak-hunting valveHV003, HV005 to ensure they have no

water, and prove that HV001, HV007, HV002 and HV004 are sealed.

d) Close washing water preparation station hand-operated valveHV008

8) Make sure that position detector and revolution detector have be switched on.

9) Make sure that main motor, low-speed motor and oil pump motor have been switched on

10) Make sure that smoke and gas inlet baffle UV01D, UV01C, heat primary air outlet

baffle UV01B and servo motor heat secondary air outlet baffle UV01A have sent off

electricity and is in the closed state.




11) Put in bearing oil system and cooling water

a) Open force-bearing bearing oil-receiving valveHV022 and oil removing valveHV024.

b) Open the cooling water-receiving valveHV020 and removing-valveHV021 of the oil

cooler to make sure that the cooling water flows smoothly.

c) Open the cooling water receiving-valveHV010 and removing-valveHV011 of

the guiding bearing oil cooler.

12) Check-up of oil system and duplex strainer

a) Make sure that the filter is complete and that duplex three-way valve HV012 (HV023)

is normally placed and is flexible in switch, and that differential pressure

gauge indication is correct.

b) Use single control on the DCS to launch bearing lubricating oil pump,

check the pressure difference of duplex filter.

c) Examine the oil system to make sure has no there is no oil leakage and see to it that

the safety valve of pipe is in the re-seating state without leakage.

d) Stop the oil pump when the check-up is done

13) Locally try low-speed motor and examine the following items in initial start-up after the

maintenance

a) Make sure that the moving direction of air preheater is right

b) It should be free of blockage and noises, and is flexible in turning

c) Make sure that speed reducer sounds normally and hydraulic couplers have no oil

leakage.

d) If something abnormal is detected in the trial, the trial can not be resumed until errors

have been removed

8.3.2.2 Operation of air preheater

1) Start-up of sub group level

a) Make sure that the check-up before start-up is done

b) Operate the manipulation (HSN001) on the DCS to issue start-up order




c) Low-speed motor should be tripped if it is in the process of operating, and when it

stops validating, main motor will start working with green light off and red light on.

d) Force-bearing and guiding bearing oil pump enter into linkage back-up uses

e) Smoke and gas inlet baffle and heat secondary air outlet baffle automatically open

f) Heat primary air baffle (UV01B) remains closed until corresponding primary blower

starts

g) When the air preheater is operating at a low speed, the low speed

motor will automatically stop when the subgroup starts, and main motor also starts,

which, if

20mins after start-up, still can not reach normal speed will automatically stop, while

low speed motor automatically restart.

h) Should the above problems are met (1.2.4), resume the subgroup. If it also does not

work, resume until errors have all been removed.

2) Single control start-up

a) Confirmation of check-up before start-up

b) Use the single control start-up order on the DCS and make sure air preheater starts

operating

c) Locally open smoke and gas inlet baffle and heat secondary air baffle

3) Local start-up

a) Start-up check-up confirmation

b) Set the “remote or local” button to be “local”

c) Press the start-up button locally, make sure that air preheater starts

slowly and operates normally

d) Open the smoke and gas inlet baffle and heat secondary air outlet

baffle when necessary.

4) Maintenance and surveillance of air preheater in operation

a) Put air preheating sealing devices into operation after boiler gets ignited,

(when driven by the main motor), and operate HSN005 by using single control.




b) The right place of sector board is decided by function generator based on load.

c) Position fixed value is invariable when load is low (below 40%), it becomes variable

when the load is between 40% and 100%, and position limit (above and below) can

solely be adjusted by 4 fanning strips.

d) Prevent the device from being clamped as there is an order of automatic receding

every 24 hours.

e) Operator can issue receding order either by operating HSN005 on the DCS, or by

pressing button local.

f) Regularly check up the air preheater to guarantee that it has no noises in operation

and its gearing is normal.

g) Make sure that the force-bearing and guiding bearing system is normal

without leakage and that the temperature of oil is at a normal level.

h) Make sure the smooth circulating of cooling water and normal

temperature of backwater.

i) After the air preheater has been charged (at a normal or lower speed), when the

temperature of bearing increases to over 60℃, oil pump will automatically start up,

and it automatically stop when the temperature return to

50 ℃ (FRA/B,

TSH15,TSH25). Still, check the air duct to guarantee that it is without air leakage

when the oil temperature of guiding bearing increases, if the problem exists, notify

repair workers to work on it in time.

j) Report to chief and shift chief-operator immediately should there be serious leakage

of bearing lubricating oil and cooling water in operation.

k) In operation, rationalize burning to avoid a second time burning, strictly supervise the

temperature of air preheater smoke and gas in and out, and

regularly do soot-blowing, for example, the job of soot-blowing should

be reinforced as the pressure difference between air preheating smoke in and

out increase.

l) During operation, strictly supervise the air preheater outlet and inlet and primary and

secondary air temperature. If any abnormal is detected, take measures immediately.

m) Normal functioning

n) Air preheater soot-blowing






o) Use the flame measure the temperature difference between air temperature of air

preheater outlet and that of heat-up component outlet. When it exceeds 50℃, the

controlling room should give off warning signal.

8.3.2.3 Halt of air preheater

1) Do not halt the operation of air preheater until the smoke temperature in outlet is at a

degree of more than 175℃ after stopping burning.

2) Stop operation, give subgroup stop order(HSN001) through DCS.

a) Main motor ceases to run

b) Force-bearing and guiding bearing oil pump automatically stops.

c) Heat secondary air outlet baffle automatically closes

d) Smoke and gas inlet baffle automatically close

e) If heat alternative stops burning, yet air preheater keeps on functioning,

normal check-up maintenance should be done

f) If there be repair work after the burning of boiler, cut off main motor and low-speed

motor power

8.3.3 Induced fan

8.3.3.1 Check-up before the start-up of induced fan

1) Check the basic principles and rules for basic check-ups

2) Adjustable baffle can give electricity and normally switch

3) Inlet and outlet baffles can give electricity and completely open and close as well

4) Motor has delivered power

5) Local button is sound

6) Every circuit measuring and protective devices are checked out and put into use

7) Requirements for start-up of themal regulator are met

8.3.3.2 Start-up of induced fan

1) Conditions for start-up




a) Air preheater on the corresponding side is operating.

b) Vibration of air fan is slight.

c) At least inlet and outlet baffles of one force fan are openned.

d) Corresponding inlet vane is closed.

e) Corresponding outlet truncated baffle is closed.

f) Every oil gun air baffle is opened.

g) Open A, B and C secondary air regulating baffle and tertiary air regulating baffle as

well.

2) Sequential control start-up

a) Using DCS, send out induced fan subgroup control start-up order, with the green light

off and red light on.

b) After conditions for start-up are met, confirm and complete requirements

asked of induced and force fan and inlet and outlet baffles as well.

c) Outlet baffle automatically opens 30 seconds later, and inlet adjustable baffle is

“automatic”.

d) When the induced fan on the other side is not running, its outlet baffle automatically

closes.

e) When the induced fan on the other side has began functioning, start

the second induced fan, when the motor is started , it will automatically open the

outlet baffle, the inlet adjustable baffle of these two induced fans should be adjusted

correspondingly, and “automatic” should be put in.

3) Start-up by hand

a) Set “manual” on inlet adjustable baffle

b) Make sure that requirements for start-up are met

c) Using DCS, send out induced fan single control start-up order and make sure that the

induced fan starts normally.

d) Open outlet baffle




e) Set inlet adjustable baffle to be “automatic”.

f) When the induced fan on the other side is not operating, close its inlet

and outlet baffle.

g) If the induced fan on the other side has began operating, open the outlet baffle by

hand when the motor is started, and put in automatic when the opening of these two

inlet adjustable baffles are adjusted consistently.

8.3.3.3 Maintenance and surveillance

1) Regularly check the induced fan

2) Make sure that bearing oil level is at a normal level and is good in quality.

3) Make sure that transmission gear is complete and functions normally.

4) Examine the temperatures of induced fan bearing, motor and bearing, vibration should be

normal and be in line with BTG operational inspection value.

5) Vibration of the air fan should be less than 120μm

6) When bearing temperature reach 90℃, warning signal should be given off, and when it

reaches over 105℃, operation should be stopped.

7) When motor bearing temperature reaches 90℃, a warning signal should be given off,

and when it reaches over 105℃, operation should be stopped.

8) When of coil temperature reach 100℃, a warning signal should be given off, and when it

reaches more than 120℃, operation should be stopped.

9) Current of motor should be less than rated current

8.3.3.4 Out-of-operation of induced fan

1) Sequential control stops

a) Outlet baffle is “automatic”

b) Force fan on the corresponding side has stopped running

c) Use DCS to issue “stop” order

d) This induced fan stops operating with red light off and green light on. The current is

“zero”




e) When the induced fan on the other side is running, outlet adjustable baffle and inlet

baffle of the former fan automatically close.

f) Stop of the last induced fan:

g) Corresponding force fan and primary fan have stopped operating, and the inlet and

outlet baffles of a force fan automatically start.

h) Use sequential control to stop the last induced fan

i) Outlet baffle of the two induced fan close 15mins after it automatically opens

j) Set the inlet adjustable baffle to be “manual”, and make it “zero”.

2) Manual operation suspension

a) Stop the corresponding force fan

b) Set the inlet adjustable baffle of the suspended fan to be “manual”.

c) Gradually narrow the inlet adjustable baffle and take care to keep the draft of hearth.

d) Manually execute the “stop” order and wait for the stop of the induced fan.

e) Close outlet and inlet baffles.

f) When stopping the last induced fan, open the outlet and inlet baffles of

these two induced fan, and appropriately open the inlet adjustable baffle according to

the draft of hearth, and what is more, close all baffles 15mins after draught.

8.3.4 8.3.4 Force fan

8.3.4.1 Conditions for start-up

1) Corresponding air preheater is running

2) Corresponding induced fan is running

3) Its inlet and outlet baffles should be closed

8.3.4.2 Sequential control start-up

1) Make sure that the inlet baffle of the induced fan is set “automatic”

2) Make sure that the cooling air balanced baffle in the force fan which waits for start-up is

closed.




3) Open the outlet and inlet baffles of another force fan.

4) After issuing the “start” order for waiting force fan on the DCS, confirm and complete all

conditions for start-up.

5) The force fan then slowly starts, with green light off and red light on.

6) 30 seconds later, inlet baffle will automatically open, manually open inlet adjustable baffle

to 10% (the inlet adjustable baffle can be directly set “automatic”).

7) Cooling air balanced baffle automatically opens.

8) When another force fan is not running, its outlet baffle automatically closes.

9) If the force fan on the other side is already running, outlet and cooling air balanced baffles

will automatically open 30 seconds after the second force fan low-speed

motor gets started. Manually adjust the opening of the two force fan inlet

adjustable baffles and make them consistent. The opening degree is decided by total load

demand multiply 30%,

and the inlet adjustable baffle of the force fan can be set “automatic”.

8.3.4.3 Manual start-up

1) Set inlet manual adjustable baffle of the start-waiting force fan to be “manual”.

2) Open the inlet and outlet baffles of another force fan on the other side.

3) Close cooling air balanced baffle on the waiting side that wait for opening.

4) Operate single control “start” order.

5) Force fan now starts slowly.

6) Open the outlet baffle 30 seconds later.

7) Open the side cooling fan balanced baffle.

8) If the force fan on the other side is not running, make sure that its inlet baffle is closed.

9) Gradually open the inlet adjustable baffle, and set “automatic”.

10) If the force fan on the other side is running, start the second force fan, and 30mins

later, manually open the outlet baffle and cooling balanced baffle, also, adjust the inlet

baffle of the two force fans to be consistent and set “automatic”.





1) When the force fan is running at a high speed, its current should be less than the rated

current.

2) When the hearth blows, the amount of air should be between 25%MCR and 40%MCR.

3) Amount of air/that of burning should be more than 9kg/kg

4) Vibrating should be less than 120μm

5) Temperature of bearing should be more than 90℃ (warning)

6) Temperature of motor bearing should be more than 90℃(warning)

7) Temperature of coil should be more than 100℃(warning)

8.3.4.5 Operation suspension of force fan

1) Set the inlet adjustable baffle to be “automatic”

2) Using DCS, issue the “stop” order.

3) When the force fan stops running, green light turns on while red light goes out.

4) Automatically close the inlet and outlet baffle if the force fan on the other side is running.

5) Automatically close cooling balanced baffle.

6) Outlet baffle will automatically open after the two force fans have stopped operating, and

it will automatically close 15mins later when inlet adjustable baffle is switched to

“manual”.

Single control operation suspension of force fan

1) Manually narrow the inlet adjustable baffle until it reaches zero

2) By solely executing the “stop” order, stop the running of force fan.

3) If another force fan is running, make sure that the outlet baffle of the former one is closed.

4) Close the suspended side cooling balanced baffle.

5) After these two force fans stop operating through the single control order, using DCS,

manually open their inlet baffles and have them closed 15mins later.




8.3.5 Primary air fan

8.3.5.1 Conditions for start-up

1) Air preheater on the corresponding side should be in operation

2) Induced fan on the corresponding side should be in operation.

3) Inlet and outlet baffles of start-waiting primary air fan should be closed.

4) Heat primary air valve of the air preheater outlet on the corresponding side should be

closed.

5) Vibrating of air fan on the start-waiting side should be slight

8.3.5.2 Start up of subgroup control

1) After making sure that conditions for start-up are met, using DCS, issue the subgroup

control order.

2) Primary air fan starts running with green light off and red light on.

3) 1min after the primary air fan starts, its outlet baffle will automatically open, so will heat

primary air valve of the air preheater.

4) Gradually open inlet adjustable baffle and set primary air pressure and inlet baffle to be

“automatic”.

5) After the second primary air fan starts operating, using hand, adjust the opening of 2 inlet

adjustable baffle to be consistent and set them to be “automatic”.

8.3.5.3 Start-up of single control

1) Make sure that conditions for start-up are met

2) Set the inlet adjustable baffle to be “automatic”

3) Through single control, execute the “start” order

4) This primary air fan then starts operating, with red light on and green light off.

5) 1min later, open the inlet baffle plate by hand

Gradually open inlet adjustable baffle plate and set it to be “automatic”.





1) Normal level of primary air pressure should be at 38mbar, when it drops to 30mbar or

less, sound the alarm

2) Give 10 seconds for coal pulverizer to trip when the primary air pressure reaches 24mbar

or less

3) Current of air fan should be less than 59A

4) Vibration of air fan should be less than 80μm

5) When the temperature of bearing reach 85℃, a warning sign should be given off

6) When temperature of motor bearing reach 90℃, a warning sign should be given off

7) When temperature of coil reaches 100℃, a warning sign should be given off

8.3.5.5 Out-of-operation of primary air fan

1) Subgroup control suspended operation

a) Issue primary air fan subgroup control “stop” order through DCS

b) Make sure that the air fan stops operating

c) Inlet adjustable baffle automatically turn to “zero”

d) Outlet baffle automatically close and heat primary air will automatically shut

down baffle

2) Single control operation suspension

a) Gradually close the inlet adjustable baffle by hand until it reaches zero

b) Execute “stop” order

c) Make sure that the air fan stops operating

d) Close the inlet baffle by hand

e) Make sure heat primary air baffle automatically close

8.3.6 Pulverizing system

8.3.6.1 Check-up before start-up

1) Start and check rotating machine (refer to basic requirements)




2) Make sure that pipelines of the system are air proof, free of power leakage and power

accumulation and that they have no fire threat

3) Make sure that blast-proof valve of the system is complete

4) Make sure that all air lock HV005,012,022 are flexible in movement and strictly closed

5) Make sure that all thermal signal of control panel and control device are

sound and useable

6) Safety interlock security test is up to standard

7) Fire-fighting equipment is complete

8) Check the lubricating oil system

a) Oil level of oil tank is normal, when it reach over 450 litre, its height should be 2/3

that of the original.

b) Temperature of oil tank is at a normal degree

c) Quality of oil should be fine

d) Oil quality of reducer should be fine and oil level should be at 1/2

height of the original

e) Strainer of main oil system and reducer oil system should be clean and flexible in

swift

f) Connection of system piping should be sound and free of oil and water leakage

g) All valves are rightly placed.

8.3.6.2 Operate all coolers

1) Operate low pressure oil pipe oil cooler:

a) Open cooling water outlet and water inlet valve of cooler, close the bypass valve

b) Make sure there is a cooling water flow (20m3 /h).

c) Put in main reducer cooler

d) Open cooling water outlet of oil cooler and front and rear doors of

temperature-controlling valve (bypass valves closed), and open water inlet valve




e) Make sure that there is a flow of cooling water

2) Put into use the main motor cooler of ball mill

a) Open cooling water outlet valve of water cooler and water inlet valve, cooling water

outlet valve of main motor bearing and water inlet valve as well.

b) Make sure that the cooling water flow is right

8.3.6.3 Check-up of powder-manufacturing equipment

1) Ensure that coal feeder has no sundries, scraper chain is complete,

pulverized coal discharging pipes are smooth, all inspection holes are closed, and coal

level of raw coal bunker is sufficient.

2) Gear wheel seal cover of ball mill should be sealed and seal fan 008ZV is reliable and

acts as back up.

3) Air drive guide baffles of cyclone separator UV10, UV20 can rightly operate

and are reliable in action.

4) Exterior of feeder is complete, interior strict without accumulated powder and mechanical

parts test normally.

5) The inspection of pulverized coal discharging machine is the same as

that of the pulverized coal conveyer.

6) Pulverized coal bunker is closed tightly, pulverized coal level measuring device is correct.

7) All valves of the system should be in the following positions:

a) Motor-operated main valves for adding steel ball are closed.

b) Motor-operated sub-valves for adding steel ball are closed.

c) Pulverized coal discharging plugboard and hot smoke hand-operated valve of the

coal feeder are open and the air-operated valve is closed.

d) Air cooling valves are closed.

e) Hot air regulating valve is closed.

f) Hot smoke bypass valve of ball mill is in a state of opening of commissioning.

g) Air-operated guide baffle of cyclone separator is directed to the pulverized coal




bunker.

h) Air-operated plugboard UV06 between pulverized coal conveyer and pulverized coal

bunker is closed.

i) Pulverized coal-discharging valve of bunker is closed

j) Outlet of cyclone separator is closed

k) Inlet valve of coal pulverizer exhauster is closed, recycled air valve in the outlet is in

the state of opening of commissioning, air fan bearing cooling outlet is closed and

inlet thereof opened.

l) Exhaust air fan inlet regulating baffle is closed and outlet valve is closed.

m) Exhaust air pipe cooling air valves are opened

n) Moisture-absorbing pipe valves of coal bunker are opened, and moisture-absorbing

pipe communicating valves are opened as well.

o) Controlling power and utility power of various rotating machines are reliable.

8.3.6.4 Operation of coal pulverizing system

1) Get lubricating oil system started

a) Controlling Power and utility power are prepared, and lubricating oil system

is in normal condition.

b) Group control start-up (on DCS): execute group control order, lubricating oil system

group control procedures automatically go on

1) Main speed reducer oil pump is got started.

2) When oil temperature of main oil tank is not more than 35℃, low pressure oil

pump will start operating.

3) When oil temperature reaches 10℃ or more, low pressure oil pump get started

4) When oil temperature reaches 35℃ or more, top tiles and jacking oil pump get

started

c) Single control start-up

1) Get it started in sequence on DCS.




2) Start-up conditions, procedure and group control start-up.

d) Local surveillance of lubricating oil system start-up:

Speed-reducing oil pump starts normally, and the oil flow is not less than

60 litre every second.

Low pressure oil bump starts normally, and oil pipelines have no

vibration and leakage.

Bush oil-pumping pressure gauge should be more than 0.2bar, oil-pumping flow

(meter) more than 30 litre per second, and jacking oil pump inlet oil pressure (meter)

1.6bar or so.

Jacking oil pump starts normally, oil outlet pipelines have no leakage and top bad oil

pressure is somewhere between 25bar and 50bar.

Jacking oil pump starts normally, oil outlet pipeline have no leakage, and

jacking pressure is somewhere between 35bar and 60bar

2) Setting value of lubricating oil system and their relations

Main oil tank:

a) When oil level is low (less than 450 litre), low pressure oil pump will trip, so will high

pressure oil pump and coal pulverizer chain

b) When oil temperature is less than 10℃, low pressure oil pump will trip

c) When oil temperature is less than 35℃, jacking (oil) pump will trip

d) When oil temperature is less than 35℃, electric heater will automatically

put into action

When oil temperature reaches more than 40℃, electric heater will automatically stop.

Low pressure oil pump exporting oil temperature is 8bar, when it reaches 12bar

or more, safety valve should be in place

Oil temperature after cooler is 45℃, temperature control valve will automatically regulate

off

When pressure difference of filter reaches 1.5bar or more, a warning signal should be given




When temperature of low pressure pipelines reach 60℃ or more, coal pulverizer will trip

trip.

When bush oil flow of coal pulverizer is less than 30L per second, the sub-coal pulverizer will

When the oil pressure of oil pump inlet of top pad and jacking is 1.6 bar, the constant pressure

valve will automatically adjust; when the oil pressure is equal to or more than 1.8 bar, the safety

valve will trip while PSL111 coal mill trips and the oil pumps of top pad and jacking trip when the oil

pressure is 0.2 bar.

When oil pressure of jacking pump reaches 60bar or more, safety valve trips.

When oil pressure of jacking pump reaches 110bar or more, safety valve trips.

When oil temperature of jacking pump is too low, say 15bar, jacking oil pump will trip (coal

pulverizer trips)

trip

When oil temperature of jacking is too low, say 30bar, jacking oil pump and coal pulverizer will

When oil temperature of speed reducer reaches 65℃ or more, a warning signal should be

given off

1) Pressure difference of filter is too high, the alarm is given.

2) Oil flow is too low, say 60 litre per min, oil pump of speed reducer and coal pulverizer will

trip

Big gear fueling injection equipment: big gear fueling injection air atomizing pressure is less

than PSL201, 4bar, send off warning signal

Stop the operation of lubricating oil system in case of the following situations

Lubricating oil system needs repair

Lubricating oil system lose great amount of oil and stop operating because of accidents

3) Subgroup control start-up of coal pulverizing system

Requirements for start-up

a) Remote and local button of its transmission should be set at remote

b) Lubricating oil system functions normally




c) Its transmission has no vibration and high alarm

d) When temperature of bush coal mill is less than 70℃, it is at a normal level, as is motor

bearing when its temperature is less than 90℃.

e) Boiler safety protection device should be set MFT resetting, and control and drive power

of all equipment belonging to the coal pulverizing system should be reliable

f) Flow of steam should be more than 270T/H.

g) Inlet adjustable baffles of both air-lack air fan and coal pulverizer exhauster should be

fully closed.

h) Temperature of coal pulverizer inlet should be less than 128℃.

i) Gigger braking device “loose”.

j) At least one of adding steel motor -driven main valve and sub valve should be closed.

k) Thermal signal should be correct, and noise-measuring device of coal pulverizer should

be put into use

l) Revolution local controlling tank switch of coal feeder should be set “on”

m) Star-up preparation on the DCS

Exhaust air quantity should be set between 30000 Nm3 /h and 40000Nm3 /h

Temperature of coal pulverizer outlet should be set at 115℃

Inlet adjustable baffles of air-lack air fan, hot air and cool air should be set “automatic”, rev of

coal supply should be set “zero” and “automatic”

Start-waiting coal pulverizing system will be repositioned

Start the exhaust air circuit (on DCS)

a) Execute subgroup control order

1) Start the exhaust air fan

2) Cooling air baffle of exhaust air fan inlet will be closed while its outlet baffle will be

opened 30 seconds after it gets started

b) Inlet adjustable baffle be set “automatic”, fixed value of exhaust air quantity should be set




Start mill-exhausting circuit

Execute subgroup control start-up order

1) Mill exhauster gets started

2) Inlet baffle UV02 will open 30 seconds after mill exhauster gets started

Start hot smoke circuit

Execute subgroup control HSN007 start-up order

1) Get hot smoke air-drive truncated baffle UV05 started

2) Inlet adjustable baffle of exhaust air fan automatically open, adjust the fixed

value of exhaust air quantity

3) Adjustable baffle of hot air and cool air automatically adjust, temperature of controlling

coal pulverizer outlet gradually increase until it reaches its fixed value

4) Draft of coal pulverizer outlet and mill exhauster inlet then gradually increase

Start the coal pulverizer

Execute the sub group start-up order when temperature of coal pulverizer inlet reaches more

than 90℃

1) Start auxiliary motor, have ball mill slowly operate, and 2mins later, unplug the auxiliary

motor and plug the main motor

2) Get big gear seal fan started

3) Put big gear oil blooming system into use

If seal fan does not operate, coal pulverizer (main motor) will trip

To restart coal pulverizer, use single control seal fan(on the DCS) when it is normal

Start coal feeder

Execute subgroup control start-up order

1) Local controlling tank is electrified 5 seconds after it gets started

2) Speed-controlling device of coal feeder will be put into a automatical control state 5

seconds after coal feeder and controlling tank are electrified.




3) After the coal pulverizing system gets started, see to it that temperature of coal pulverizer

inlet slowly increase until it reaches its fixed value, and that the adjustable baffles of hot

air and cool air are in the automatic position, and that noise-measuring indicator of coal

pulverizer chang from high to low until it reaches normal value

4) Group control of coal pulverizing system

Conditions for start-up

Start preparation on the DCS:

Start-waiting coal pulverizing system reseats.

Exhaust air flow control reture circuit, temperature-controlling circuit and speed-controlling

A/H order of coal feeder are all “automatic”.

Sub group start-up conditions are met.

Group control start-up

Execute HSN001 group control start-up order.

1) Get exhaust air fan circuit started through automatic sequencing.

2) Get mill exhauster started through automatic sequencing.

3) Start hot smoke circuit through automatic sequencing.

4) Inlet baffle of exhaust air fan automatically adjust exhaust air flow.

5) Adjustable baffles of hot air and cool air automatically adjust coal

pulverizer inlet temperature until it reaches 90℃.

a) If gigger motor is operating, it will trip.

b) Coal pulverizer automatically starts through automatic sequencing.

c) Coal feeder automatically starts through automatic sequencing, rev control circuit of

coal feeder will automatically adjust coal supply quantity.

6) Maintenance and parameter during operation

Adjustment of coal pulverizing system in operation

a) Objectives of adjustment




1) Make sure that the fineness degree of coal powder is up to standard and is fine in

evenness degree to avoid incomplete burning loss

2) Guarantee the best output of coal pulverizing system, and try to

lower power consumption of milling

3) When boiler functions safely and economically, guarantee coal powder supply and

sufficient coal level to suit the change of load, and ensure that there

is enough buffering time when coal pulverizing system fails

b) Adjustment and instruction in operation

1) Coal feeding speed adjustment

Coal feeding speed adjustment automatically proceeds according to the

signal of noise-measuring device, and it works in the manner of “automatic”.

In face of the problem of manually adjusting coal feeding amount, when

slowing down or quickening speed, ensure that the coal feeding is slow

and consistent, starting or closing the coal feeder to adjust coal feeding is banned

2) Adjustment of exhaust air amount

Inlet adjustable baffle of exhaust air fan should be “automatic”

Flow amount of exhaust air can be changed through exhaust air amount enactment,

and when humidity of raw coal is high, increase exhaust air amount properly

3) Adjustment of coal pulverizer inlet temperature

Adjustable baffles of hot air and cool air should be “automatic”, the opening of hot air

adjustable baffle appropriate, and cool air adjustable baffle closed.

With coal pulverizer outlet temperature enactment, hot air and cool air

adjustable baffles should be automatically adjusted, aimed at adjusting coal

pulverizer outlet temperature.

Restriction loop is used to avoid temperature rise at coal pulverizer entrance, the

temperature of coal pulverizer inlet should always be higher than

secondary air temperature (minimum temperature difference △T=20℃)

If outlet temperature falls too much (about10℃ lower), coal feeding

revolution slowly drops by connecting revolution slide system until it

reaches normal




temperature value

4) Noise control of coal pulverizer

If coal pulverizer noise drops too much to avoid the blocking of coal pulverizer, coal

feeder revolution is automatically shifted to 20% that of its rated revolution

5) Hot smoke bypass valve HV002 of coal pulverizer

Manual baffle HV002 can control coal powder circulation amount from raw powder

separator to coal pulverizer (when it is closed, the baffle increases the coal powder

circulation amount, and it can only be adjusted once in the test)

6) Mill exhauster recirculating valve HV003

In debugging, fix its opening which should not be changed in operation

Mill exhauster air current carries the powder from coal pulverizer

through raw powder separator into cyclone separator, and to avoid the

accumulation of coal powder in the pipelines, the speed of gas in the pipes

should be as much as that of the fixed minimum value

7) Adjustable baffle of raw powder separator

Its function is to adjust the effect of raw powder separator to ensure the fineness of

coal powder is up to standard, and in debugging, fix its opening

level which is generally not adjusted in operation

When its opening enlarges, draught of the system and coal pulverizer will increase

and coal powder become thick

When the fineness of coal powder passes 200 in normal operation, objective should

be between 92% and 95%.

c) Operational parameters of coal pulverizing system

Temperature monitoring

1) Normal value of coal pulverizer inlet hot smoke air temperature is somewhere between

350 and 700℃, when it reaches upper limit of 800℃ and lower limit of 300℃, a warning

signal should be given off.

2) Normal value of coal pulverizer inlet temperature is 115℃, when it reaches 120℃ or is




less than 90℃, a warning signal should be given off, when it reaches 130℃, exhaust air

and mill exhauster will trip, so will interlocked coal pulverizing system

Air pressure monitoring

1) Normal value of coal pulverizer outlet draft should be somewhere between 20mbar and

30mbar

2) Inlet draft of mill exhauster should be equal to 70mbar of less

Exhaust air amount should be 40000Nm3/h or less

Powder level of coal bunker should be maintained a level higher than 8 meters, when it is 3

meters high or less, a warning signal will sound and pulverized coal feeder will trip. When it is 11

meters high or more, sound the alarm, and when powder level reaches 12.5 meters, stop the coal

pulverizing system or remove powder to another coal bunker on the other side

Electric current value of rotating machine

1) Value of exhaust air fan should be less than that of rated electric current

2) Rated electric current value of mill exhauster should be less than that of rated current

3) Rated electric current value of coal pulverizer should be less than that of rated electric

current

Inspection and maintenance of coal pulverizing system in operation

Inspectors should regularly check all equipment, checking the functional

status of all equipment, collating local instrument and control room numerical value, and

immediately reporting and acting to deal with problems when something abnormal happens.

Operational parameters of all auxiliary organs should be controlled within the following scope

1) Coal pulverizer

Normal temperature value of bush should be at 45℃ or so and less than 70℃.

Main motor bearing temperature should be less than 90℃

Coil temperature of motor should be less than 100℃

Cooling water flow of main motor cooler should be at a normal level

Cooling water flow of main motor bearing should be at a normal level




2) Mill exhauster

Bearing temperature should be at a degree lower than 90℃

Bearing temperature of motor should be at a degree less than 90℃

Coil temperature of motor should be at a degree less than 100℃

Bearing vibration should be less than 80μm, when it passes 80μm, air fan will trip

Cooling water amount of motor should be normal

3) Exhaust air fan

Bearing temperature should be at a degree less than 90℃

Bearing temperature of motor should be at a degree less than 90℃

Coil temperature of motor should be at a degree less than 100℃

Bearing vibration should be less than 80μm, when it passes 80μm, air fan will trip

Cooling water amount of motor should be normal

4) Lubricating oil system

Oil temperature of main oil tank should be somewhere between 35℃ and 40℃

Oil level of main oil tank should be 1/2~2/3 of its original height (based on on-site oil level

gauge)

Bush oil-receiving flow amount of coal pulverizer should be more than 30 litre per second

Pressure difference of oil filter should be less than 1.5bar normally, when it reaches 1.5bar or

more (PDSH102), rearrange the oil filter and notify workers for maintenance and clean the oil filter

that has been blocked.

Top pad oil temperature should be somewhere between 25bar and 50bar (normally it is 30bar

or so)

Jacking oil temperature should be somewhere between 35bar and 60bar (normally it is 40bar

or so)

Oil system has no vibration and oil leakage

5) Oil system of speed reducer




Oil system should be free of oil leakage

Oil flow should be more than 60 litre every minute

When pressure difference of filter is too great, change the filter and notify repair workers for

maintenance and clean the one that has been blocked

Cooling water flow indictor of cooler should be placed in the protection zone

6) Big gearwheel grease-blooming system

Oil in the oil barrel should be sufficient, if oil shortage problem is found, notify oil inspectors to

refuel in time

Motor-driven pump and oil blooming should be normal

When electromagnetic valve rear pressure reaches 4bar (PSL201), sound the alarm.

8.3.6.5 Suspended operation of coal pulverizing system

1) Subgroup control stops (on DCS)

a) Set the speed-controlling device of coal feeder to “manual” status to bring the speed

down to zero

b) Operate the subgroup control stop order and stop coal feeder

c) After the coal feeder stops, make sure that coal in the coal pulverizer have all been

removed and its outlet draft diminish, and when outlet temperature passes 120℃,

operate the subgroup control stop order.30 seconds after coal

pulverizer stops operating, assistant motor gets started (assistant

motors can be stopped by operating the local or emergency

order), and 30 minutes later, seal fan will automatically stop (it can

also be realized by operating the single control stop order

on the DCS).

d) Operate the subgroup control stop order, make sure that hot smoke air drive baffle

and inlet adjustable baffle of exhaust air fan, and hot air and cool air adjustable baffle

plate automatically close

e) Operate the subgroup control stop order, mill exhauster will stop and its inlet baffle

plate will automatically close

f) Operate the subgroup control stop order, exhaust air fan will stop operating, and its

inlet and outlet adjustable baffles will automatically close, whereas cooling air baffle




in the exhaust air vent will automatically start

2) Group control stop (on the DCS)

a) Carry out the group control stop order and stop proceeding the procedures.

b) Coal feeder stops operating, and the opening speed-controlling device drops to zero

c) 15 minutes after coal feeder stops operating, its subgroup control circuits also cease

successively

8.3.6.6 Emergency automatic stopping and tripping of the pulverizing system

1) The pulverizing system trips when one of the following conditions is met

a) ‘Emergency stop’ command is operated

b) Boiler MFT action is done.

c) A ball mill trips when the pulverizing system is treated with group control.

d) If one of the above conditions occurs, the following steps should be operated at the

same time

e) The coal feeder trips automatically

f) The main motor of coal mill trips automatically and the helper motor starts up after 30

seconds.

g) The hot smoke air circuit trips automatically

h) The pulverized coal exhaust circuit trips automatically

i) The exhaust gas circuit trips automatically

2) The tripping of each subgroup control circuit

The exhaust gas circuit trips when one of the following conditions is met

a) Action of the boiler MFT is done

b) The outlet temperature of the coal mill is equal to or higher than 130 degrees

c) Steam flow<270T/H with 3 minutes’ delay

d) Vibration of exhaust gas fan ≥80μm with 10seconds’ delay




e) After the start-up command is given two seconds, the exhaust gas fan motor has no

electricity.

f) The group control commands or subgroup control commands are done

The pulverized coal exhaust circuit trips when one of the following conditions is met

a) When the start-up command is given 90 seconds, the entrance truncated baffle is

not open

b) The outlet temperature of the coal mill is equal to or higher than130 degree

c) Action of the boiler MFT is done

d) The pulverized coal exhauster vibrates too sharply with 10seconds’ delay

e) After the start-up command is given 2 seconds, the pulverized coal exhauster motor

is not switched on. The group control commands or subgroup commands are done

The hot smoke wind circuit trips when one of the following conditions is met

a) The exhaust gas fan motor is powered off

b) The pulverized coal exhauster motor is powered off

c) The pulverized coal exhauster entrance baffle is not opened completely

d) The lubricant circuit of the coal mill is not put into operation

e) After the start-up command is given 30 seconds, the hot smoke baffle is not open

f) One tripping command is given from the group control or subgroup control

The coal mill trips when one of the following conditions is met

a) The lubricant circuit of coal mill is not put into operation

b) Any top bearing oil pressure is equal to or less than 30bar (top watt pressure≤15bar)

c) Any top watt oil blooming flow <30litre/minute with 5 seconds’ delay

d) The oil temperature in the oil tank is equal to or higher than 60 degree, or less than

35 degrees.

e) The lubricant circuit of the coal mill is not put into operation.




f) The lubricant circuit of the coal mill is not put into operation.

g) The alarm issues when cooling water flow is low.

h) The temperature of top watt is equal to or higher than 70 degree.

i) The locking pole of turning gear leaves the position.

j) Both of the two steel tubes with electric valves are not closed

k) After the main motor is started up 2 seconds, the centrifugal intermittent device of

the turning gear is in a closed position

l) After the main motor is started up 2 seconds, the seal fan is not started up

m) Switch to the operation of the turning gear is required

n) The time of the oil blooming system’s fault is more than one hour

o) The hot smoke air baffle is not open

p) Action of the boiler MFT is done.

q) The entrance fuel pressure of the high pressure fuel pumps is equal to or less than

0.2 bar

r) One group control command or subgroup command is done

s) After the main motor of coal mill is powered off 30 seconds, the auxiliary motor is

started up

The coal feeder trips when one of the following conditions is met


b) The pulverized coal level of pulverized coal bunker is too high (LSHH06A/06B)

c) The main motor of coal mill is powered off

d) The baffle of hot smoke air is not open.

e) After the coal feeder is started up 25 seconds, the speed of revolution is too slow

f) After the coal feeder is started up 2 minutes, the coal is not supplied and with 30

seconds




g) One stop command from the group control command or subgroup command is done

8.3.7 The turning gear of the ball mill

8.3.7.1 Regulations about operation of the turning gear

1) When the pulverizing system is stopped while the rotating equipment has no fault

2) When adopting mechanical supervision to the coal mill

3) Before starting up the coal mill after being stopped a long time, the lubricant system must

be adjusted in the state of turning gear

4) When the main motor is started up, the turning gear motor should be run for 2 min in low

speed.

8.3.7.2 The start-up conditions of turning gear:

1) The lubricant circuit of coal mill is put into operation

2) Speed reducer lubricant circuit is in operation

3) The temperature of bearing of the coal mil is normal

4) The main electromotor of coal mill is powered off

5) The braking device of turning gear is in the “loose” position

8.3.7.3 The start-up of turning gear

1) Start up on the spot

a) When the pulverizing system is stopped, but its rotation machine is

normal, the persons on duty should start up the turning gear until the main motor

starts up

b) Press the on-the-spot startup button to start up the turning gear when mechanical

inspection is needed, or operation of coal mill at slow speed is

needed for adjusting the lubricant system

c) When the start-up command is given, electromagnetism gear and auxiliary motor is

electrified at the same time

8.3.7.4 The tripping conditions of turning gear

1) The lubricant circuit of coal mill is not put into operation

2) The lubricant circuit of speed reducer is not put into operation




3) The temperature of bush of coal mill is equal to or higher than 70 degree

4) The trouble time of fuel sprinkling system lasts more than one hour.t

5) After the turning gear is started up 2 seconds, the seal fan fails to start up

6) The locking pole of turning gear is not in “loose” position

7) One stop command is given

8.3.8 The pulverized coal conveyer

8.3.8.1 The inspection before start-up

1) The inspection of the mechanical section should be normal

2) The pulverized coal conveyer should not be blocked by pulverized coal

3) Accumulated pulverixed coal, light source should not be found and the lighting should be

sufficient.

4) The gas source of the guide baffle should be normal.

8.3.8.2 The pulverized coal pouring operation of the pulverized coal conveyer(A→B)

1) Open the pulverized conveyer then lead it to the pneumatic flashboard of B pulverized

bunker, and the pneumatic flashboard should be closed when it arrives at A pulverized

bunker.

2) Open the communication valves of the moisture absorption pipe

3) Operate the startup button of the pulverized conveyer from A to B on the spot

4) Make sure that the operation of the pulverized coal conveyer is normal, the direction is

normal, the motor and the transmission device is normal

5) Lead the lowering pulverized coal guide baffle of A side of the cyclone separator to the

pulverized coal conveyer

6) Make sure that the operation of the pulverized coal conveyer is normal, and make sure

the pulverized coal has been conveyed from A to B

7) The changes of the position of pulverized coal in A, B bunker should be monitored.

8.3.8.3 The normal maintenance of pouring pulverized coal (A→B)

1) Inspect the operation of the pulverized conveyer periodically




2) The signals of the pulverized coal conveyer and the guide baffle of the cyclone separator

should be normal when being monitored by a CRT.

3) When B pulverizing system operates and pulverized coal is poured from A to B, the level

of pulverized coal in B bunker rises rapidly, the changes of the level of pulverized coal

should be should be paid.attention to.

8.3.8.4 The abnormality treatment of pulverized coal pouring:

1) When pulverized coal is poured and the pulverized coal conveyer trips, the guide baffle of

A cyclone separator is should be made sure to be led to the pulverized coal

bunker automatically

2) When the pulverized coal conveyer operates and has sprinkling pulverized coal, it should

be inspected that whether the hand-operated valve of the moisture absorption

pipe is opened.

3) When the chains of the pulverized coal conveyer are broken, the guide

baffle of A

cyclone separator should be led to the pulverized coal bunker at once, and

stop the pulverized coal conveyer

8.3.8.5 Stop pouring pulverized coal

1) Lead the guide baffle of A cyclone separator to the pulverized coal bunker on the spot,

and make sure the position of the pulverized bunker is right

2) Stop the pulverized conveyer when it has no pulverized coal

3) Shut off the pulverized coal conveyer, and lead it to the pneumatic flashboard of B

pulverized coal bunker

8.3.9 The operation of adding steel balls into coal mill

8.3.9.1 The steel balls should be added during the operation when the current of coal mill is

equal to or less than 190A,.

8.3.9.2 The operation method of adding steel balls

1) Prepare the steel balls that to be added.

2) The quantity of the added steel balls is 1 ton/ times, and the current of ball mill is rose by

about 1A

3) Operate the button of “preparation of adding steel balls” on the spot, the general electric




valve for adding steel balls are opened, and then the steel balls are filled into the locking

cavity

4) Operate the button of “adding steel balls” on the spot, then the general electric valve of

adding steel balls are closed, the electric sub-valve are opened, and the steel balls are

added into the coal mill

5) 3 minutes later, the electric sub-valve for adding steel balls are closed automatically

8.3.9.3 Attention

1) When both the general electric valve and sub-valve for adding steel balls have no signals,

the coal mill will trip.

2) After adding the steel balls, make sure that the next operation of adding steel balls should

be done only after the electric sub-valve is closed

8.3.10 The pulverized coal burner

8.3.10.1 The inspection and preparation before start-up

1) Open the pulverized coal feeding flashboard of the pulverixed coal feeder,

and the hand-operated valve of the primary air pipe is in the position for adjusting

the opening degree.

2) Various parts of the pulverized coal feeder, the speed governor and the motor should be

checked whether they are all normal.

3) The primary air pipe should not be leaked, and the platform of the coal feeder has no

accumulated pulverized coal and combustible substance.

4) Make sure that the controlled gas source of the primary air pneumatic valve is normal,

and the hand-operated valve of the controlled gas source is opened.

5) The sampling valve of the primary air pressure meter is opened.

6) The switch of the local speed governor is in “ON” position

8.3.10.2 The startup conditions:

1) The general protection of boiler is put into operation, and MFT is reset.

2) The corresponding oil gun torch is put into operation

3) The steam flow is equal to or higher than 250T/H




4) The level of the pulverized coal in pulverized coal bunker is higher than 5m

5) The hot primary air pressure is not too low.

8.3.10.3 The start-up of subgroup control (on DCS)

1) Regulate the to-be-started-up speed governor of coal feeder to “zero” (SC50A/50B)

2) Operate start-up command for the subgroup control of the front wall coal feeder or back

wall coal feeder

3) The corresponding primary air pneumatic baffle is opened.

4) After the primary air baffle is opened for 10 seconds, the coal feeder is started up

5) After the coal feeder is started up for 5 seconds, the corresponding secondary air baffle is

opened.

6) All the baffles of the A. B, C bellows are placed in the manual state, then

the speed control of coal feeder is put into operation

7) The lowest rotating speed is 3rpm, the corresponding pulverized coal’s quantity is 4T/H.

The automatic control of the fuel increase and switch is operated according to the needs

of load increase, and it should be confirmed that the pulverized coal burns well

8.3.10.4 The single control of start-up (on DCS)

1) Make sure the start-up conditions are ready.

2) The speed of the to-be-started-up coal feeder is regulated to “zero”

3) The start-up command of the single control of the corresponding primary air pneumatic

baffle is operated and the valve should be confirmed opened.

4) The start-up command of single control of coal feeder is operated, and then

the coal feeder is started up.

5) After the speed controller of the coal feeder is put into operation for 5

seconds, the corresponding secondary air baffle is opened.

6) After the coal feeder starts up normally, the rotation speed should be increased manually,

and it should be made sure that the pulverized coal burns well




8.3.10.5 The running and operation of the pulverized coal jet burner

1) The rotating speed of single coal feeder is set in “automation” (on DCS)

When the number of the coal feeder operation is increased to 8, and the rotating speeds

are all 5rpm, the rotating speed of the single coal feeder can be put into automation in

turn, and SC50A/50B is regulated by the general rotation speed. The

operation is as follows:

a) The opening degree of the general speed governor of the coal feeder is regulated to

40% (on DCS or the spare tray)

b) The speed governor of the single coal feeder is used to regulate its rotation speed in

order to adapt to the signal need of the general speed governor, and the regulation

of the rotating speed of the coal feeder is set to “automation”

c) As the methods described above, other coal feeders are set to “automation” in order.

2) The general speed governor of the coal feeder is set to “automation”

When the quantity of the coal feeder and its rotating speed is adequate, and the volume

of the pulverized coal reaches about 50%, the general speed governor can

be set to “automation” in order to balance the air volume / fuel volume

ratio automatically, the operation is as follows:

a) The demand regulator of the general load should be placed in manual state, and its

opening degree should be 45%

b) The entrance regulation baffle of the induced draft fan and forced draft

fans has been put into “automation”

c) The smoke oxygen content should be normal, and its regulator should be put into

“automation”

d) The general rotating speed of the coal mill should be set to “automation” (FEO HIC

050)

e) At this time, the general load needs, the rotating speed and the air flow of the coal

feeder should be correspondingly increased or decreased.

3) The start-up order of the pulverized coal jet burner

a) In principle, the start-up order should be operated from the middle of the arch to its




both sides, (FEF, FED) → (FEG, FEC) →(FEH,FEB) and should be put into

operation correspondingly for the front and back archs.

b) When the second auxiliary ejector is put into operation, put FEE→ (FEI, FEA) to the

coal feeder

c) The operative rate of the pulverized coal jet burner should be consistent with the

startup burning rate curves

4) Operation maintenance and supervision

a) Supervision in the control platform

The primary air pressure should be equal to or higher than 36mbar

The rotating speed change of the coal feeder should be balanced, the rotating

speed should not fluctuate substantially when “automation” is set, otherwise the speed

should

be switched to manual control and the rotating speed of the coal feeder

should be controlled equal to or less than 10rpm in order to prevent the

pulverized coal from blocking of the pulverized coal pipe.

b) Local maintenance

Various parts of the coal feeder, speed governor and motor should be

inspected and confirmed in normal condition.

The coal feeder has no abnormal sounds

The operation of the pulverized coal feeding pipe of the coal feeder is smooth, and the

temperature is normal

The pulverized coal feeding pipe and the primary air pipe has no leakage of pulverized

coal and air leakage

The local place has no blocking pulverized coal and self-ignition phenomenon

8.3.10.6 The stop of the pulverized coal jet burner

When the boiler stops, the pulverized coal feeding flashboard should be switched off before

the coal feeder stops

1) The subgroup command stops (on DCS)

a) The stop command of the subgroup control is stopped.




b) When the coal feeder stops, the speed governor will automatically return to “zero”

c) After the coal feeder is stopped for 20 seconds, the corresponding

secondary air baffle is switched off. (If the oil gun torch keeps operating, the

secondary air baffle near the oil gun torch should be opened)

d) The primary air pneumatic baffle is closed

2) Stop of the single control

a) The rotating speed of the to-be-stopped coal feeder is reduced to “zero”

b) The stop command of single control is operated and the coal feeder is stopped.

c) After the coal feeder is stopped for 20 seconds, the corresponding

secondary air baffle is closed. (the baffle keeps open when the oil gun torch is

operating) (FEA UV13, FEI UV24 single control is closed)

d) The single control demand is operated and the primary air baffle is switched off

3) The coal feeder’s stops for accident

The coal feeder trips when one of the following conditions is met


b) The operation conditions of the coal burner defined by the flame scanning system

are not fulfilled.

c) When steam flow is less than 440T/H, the corresponding oil gun torch has no flame

monitoring

d) When steam flow is less than 270T/H

e) The related pulverized coal’s level in the bunker is too low

(3m) (FMA/B LSLL06A/06B)

f) The primary air pressure is too low (FSA PSLL03) with 5 seconds’ delay (<24mbar)

g) The corresponding primary air baffle has not been opened

h) The coal feeder fails to be switched on 30seconds after the start-up

command is given.

i) The corresponding secondary air baffle fails to be not opened 2min after the start-up




command is given.

Note: Because of MFT action, if the oil gun torch is controlled in the distance, the baffle of the

secondary air should be opened, FEA UV14, FEI UV24 should be closed after 60 seconds

8.3.11 Fire detector cooling fan

8.3.11.1 Inspection before start-up

1) The air duct is complete and the system connection is good

2) The strainer at the entrance of the fan is in good condition without blocking

3) The mechanical part and the motor is normal through inspection and the transmission

belt is complete without looseness

4) The motor offers electricity normally.

5) The outlet hand-operated valves of two fans are open

6) Each oil gun torch and the hand-operated valve of flame scanning

cooling fan of pulverized coal ejector should be opened

7) The measuring points of air pressure are complete, and the local indication gauges are

correct.

8.3.11.2 The start-up of the fan

1) The start-up of the subgroup control

a) Switch off interlocking (the light is bright)

b) Operate # 1 fan and choose the command (the light is bright)

c) Operate the start-up command of subgroup control

d) Make sure AC fan is operated, the green light is put out, the red light is bright, and

the outlet air pressure is normal

e) The interlocking in put into operation, then the light is put out

2) The start-up of single control (on DCS)

a) Switch off interlocking (the light is bright)

b) Operate the start-up command of single control of # 1 fan, then #1 fan is started up




c) After the option command of HSU001 #1 fan is operated, the “ON” command of

subgroup control should be operated.

d) Switch on the interlocking (the light is put out)

8.3.11.3 The linkage and periodic test for direct current fan

1) The linkage of direct current fan

a) Switch on the interlocking (the light is put out)

b) # 1 fan is tripped, and #2 fan linked

c) When the outlet pressure of cooling air fan is less than 85mbar, and after the alarm

issues with s 5 seconds delay, #2 direct current of cooling fan starts up automatically

d) Make switch operate alternatively and automatically

Note: the switch of the flame scanning cooling fan should be operated only after some safety

measures have been adopted in order to prevent the action of the boiler MFT

2) The periodic test of direct current fan (two fans can operate simultaneously at any time)

a) The 220VDC electrical source is inspected and confirmed normal

b) Operate start-up command of single control of #2 fan on DCS, then #2 fan starts up

c) The operation of #2 fan is checked and confirmed normally running.

d) The start-up command of single control of #2 fan is operated, then #2 fan stops

e) Make sure that the flame scanning cooling air pressure should be higher than

85mbar, and the interlocking is normal (the light is put out)

8.3.11.4 Operation of maintenance and supervision

1) The operation of the fan should be periodically checked, and it should be made sure that

the fan has no friction noise and its bearing’s temperature and vibration and its motor’s

temperature are normal

2) The entrance strainer of the fan should have not blocking phenomenon,

otherwise, it should be cleaned in time

3) The driven belt has not slippery, loose, and falling phenomenon, the local air pressure

should be normal, the air duct and the connected system has not air leakage




4) The outlet air pressure of the fan should be higher than 85mbar

5) When the outlet air pressure is lower than 85mbar (PSL02), the alarm will be emitted,

and after 5 seconds delay, the direct current fan is linked

6) When the outlet air pressure is lower than 70mbar (PSLL03) with 10 seconds delays, the

boiler has MFT action

8.3.11.5 Stop of the flame scanning cooling fan

After the boiler is stopped for 24 hours, the operation of the flame scanning cooling fan can be

stopped

1) The subgroup control is stopped (on DCS)

a) Operate stop command of HSN001 subgroup control and group control, then the red

light is put out, the green light is bright

b) Make sure the fan is stopped

2) The single control is stopped (on DCS)

a) Operate HSU002, and switch off interlocking (the light is bright)

b) Operate stop command of single control, then the red light is put out, the green light

is bright

c) Make sure the fan stops

8.3.12 Oil gun torch cooling fan

8.3.12.1 Startup Check

1) Ensure the air duct is complete, and system connection is in good condition

2) Check whether the mechanical part and the motor are normal or not, and

ensure the driving belt is complete and not loose.

3) Ensure motor energization

4) Ensure the hand-operated valves of the outlets of the two fans are open

5) Ensure all cooling dampers of the oil gun torch are open and the HV*5 hand-operated

valve of the burning torch cooling air is open.

6) Ensure the air pressure measuring point is complete, and the local indicator is correct




8.3.12.2 Fan startup

1) Sub control startup

a) Switch-off interlock (lights on)

b) Select fans to be started (lights on)

c) Operate sub control startup order

d) Confirm the selected fan is started, the green light is off, the red light is on, and the

outlet air pressure is normal

e) Interlock is put into service (lights off)

2) Single control startup (on DCS)

a) Switch off interlock (lights on)

b) Operate single control startup order, and the fan is started

c) Select operation fan (lights on)

d) Operate sub control “ON” order, the green light is off, and the red light is on.

e) Interlock is put into service (lights off)

8.3.12.3 Fan in reserve and transfer

The fan transfer should be locally supervised, and should be started before being stopped.

1) Sub control transfer (on DCS)

a) Check interlock is in service (lights off)

b) Select fan to be started (lights on) and fan to be shutdown (lights off)

and the selection difference light is on.

c) Operate sub control startup order, and the difference light is off when the fan to be

started is started and the fan to be shutdown is shut down.

d) Locally checks and ensures the operation fan is normal and the air pressure is more

than 85mbar

2) Single control transfer (on DCS)

a) Single-control starts the fan to be started




b) Single-control shut down the fan to be shut down

c) Operation selects the started fan (lights on) and shuts down the fan (lights off)

d) Locally check and ensure the operation of the started fan is normal and

the air pressure is more than 85mbar

e) Ensure the sub control is at a condition of “ON”, the green light is off and the red light

is on.

f) Check interlock is in service (lights off)

3) Linkage of standby fan

a) Interlock is put into service (lights off)

b) Standby fan starts when the operation fan trips.

c) Standby fan starts in five seconds after the pressure of cooling air outlet lowers to

85mbar and an alarm is given.

d) Automatic transfer happens alternatively

8.3.12.4 Operation maintenance and supervising

1) Periodically repair fan operation, and ensure no grating, bearing

temperature and vibration are normal, and motor temperature is normal.

2) Ensure the driving belt has no skidding, looseness and shedding, the local air pressure is

normal, and the air duct and connection system have no air leakage.

3) Outlet air pressure should be more than 85mbar

4) When the fault fan is in maintenance, interlock thereof should be unlocked, the power of

the motor of the fan should be cut, and the outlet valve should be closed.

8.3.12.5 Oil gun torch cooling fan shutting down

1) Shut down the oil gun torch cooling fan after boiler is stopped for 24 hours.

2) Sub control stopped (on DCS)

a) Operate HSN001 shutting down order, the red light is off, and the green light is on.

b) Confirm that the fan is shut down.




3) Single control shutting down (on DCS)

a) Operate HSU002 to unlock the interlock (lights on);

b) Operate single control shutting down order, and ensure that the red light is off, and

the green light is on;

c) Confirm that the fan is shut down.

8.3.13 Steam air heater

8.3.13.1 Check before startup of the steam air heater

1) Ensure that the valves of the steam air heater and auxiliary device piping

are well connected.

2) Ensure the motor-operated valve has been energized, and air supply

availability is controlled.

3) Ensure the condensate system has been put into operation.

4) Ensure the auxiliary steam and the steam extraction is normal.

5) Ensure all measuring instrument is complete and correct.

6) Ensure the following instrument sampling isolating valves are open.

a) Steam inlet pressure hand-operated valve

b) Condensed water tank pressure gauge hand-operated valve

c) Condensed water tank water level high switch hand-operated valve.

d) Condensed water tank water level low switch hand –operated valve.

e) Condensed water tank water level gauge water inlet valve.

f) Condensed water tank water level regulating signal transmitter signal valve.

7) Open the steam piping upper air valve

8) Shut down the steam control valve; shut down the side valve and open the front and real

hand-operated valve.

9) Open the steam air heater desuperheater water hand-operated valve;

desuperheater water control valve auto on.




10) Open the steam air heater steam intake valve.

11) Open the steam air heater outlet valve.

12) Open the hand-operated valve of condensed water outlet and inlet of the

secondary steam air heater.

13) Open the hand-operated valve of the condensed water blowdown flash tank, manually

shut down the control valve.

14) Open the water drain valve of the condensed water tank, and close the

valve after remained water is drained.

15) Confirm that the hand-operated valve of the condensed water tank to #2

low water injection and drain tank, and manually close the control valve.

8.3.13.2 Put steam air heater into operation

Natural ventilation is adopted before the boiler ignition, the steam air heater is

put into operation, and the outlet air temperature is more than 90 degrees Celsius; in the normal

operation

of the boiler, the average temperature of the gas is maintained between 100 to

105 degrees Celsius, and the air temperature of the outlet is automatically controlled; the

steam air heater is stopped when the heater is high loaded.

1) Select mode at the “auxiliary steam” position of DCS.

2) Pass out the steam air heater sub control startup order at DCS, to confirm that:

3) The fifth extraction motor-operated valve is closed;

4) The auxiliary steam motor-operated valve is open;

5) The drain water motor-operated valve is open;

6) The stem control valve is manually and gradually opened;

7) The drainage valve is closed when the steam bursts out;

8) Condensed water tank water level gauge is checked and the water level is normal;

9) The water level control valve of the condensed water tank is “auto” on;

10) When turbine operation condition is permitted, the turbine can be set as “auto” on;

11) The steam desuperheater water control valve is set as “auto” on.




The operation of the steam source being switched over to “five section steam extraction”

should be carried out when the operation condition of the turbine is permitted, and the specific

operation is as follows:

1) Select mode at the “five section steam extraction” position of DCS;

2) Pass out the steam air heater sub control startup order to confirm that the

the steam supply motor-operated valve is open, the check valve is open

and the drain water motor-operated valve is closed.

8.3.13.3 Operating maintenance and parameter

1) The inlet steam temperature of the steam air heater should be between 130

degrees Celsius to 200 degrees Celsius and the temperature should

be higher than (at corresponding pressure) the saturation temperature by ten

degrees Celsius.

2) Drain water tank outlet water temperature of the steam air heater should be 40 degrees

Celsius.

3) Condensed water tank water level.

Water level is low alarm 300mm

Water level is high alarm 800mm

4) Inlet steam pressure

Pressure is low alarm 2bar

Pressure is high alarm 14bar

5) Secondary air temperature of air pre-heater inlet (according to the load)

6) Air and gas average temperature should be between 100 degrees Celsius to 110

degrees Celsius.

7) Flue gas temperature should be 150 degrees Celsius.

8) Condensed water tank water level governing

a) The water level control valve should be controlled by the water level control circuit at

“auto” position, thus maintaining the condensed water tank water level constantly.

b) In normal operation, drain water in condensed water tank drains into drain tank of

low-pressure heater.






c) When the water level of drain tank of low-pressure heater is extremely high and

alarm is given, the steam supply motor-operated valve will be automatically closed,

and the drain water motor-operated valve will be automatically opened,

and the condensed water gutter static expansion.

d) The water level of the condensed water tank should plus 500mmor plus 600mm.

e) When the water level auto control of the condensed water fails,

the steam supply/drain water regulating valve can be switched to “manual” operation.

8.3.13.4 Steam air heater shutting down

1) Pass out the sub control shutting down order at DCS to confirm that:

a) The motor-operated valve is automatically closed when “auxiliary steam

supplies steam”;

b) When the five section steam extraction supplies steam,

The steam extraction motor-operated valve UV01B and the check valve UV01C are

automatically closed;

The drain water motor-operated valve UV01D is automatically opened;

And the steam control valve TCV75A and the desuperheater water control valve

(TCV75B) are automatically closed.

2) Automatic shutting down of steam air heater

Steam air heater tripping conditions:

a) Pass out steam air heater sub control shutting down order at DCS;

b) The turbine trips when the five section steam extraction supplies steam.

The fifth extraction motor-operated valve and the check valve should be closed.

8.3.14 Boiler water recycle pump

8.3.14.1 Check before boiler water pump startup

1) The connection of the pump, the motor and the system should be in a good condition;

2) Check whether all valves of the boiler water pump are closed or not;

3) Check whether all instruments and the alarm system are in a good condition or not.




8.3.14.2 Put cooler into service

1) Ensure the closure cooling water system has been put into operation;

2) Ensure the water drain valve of the cooler inlet is opened, and is closed after the sewage

is drained;

3) Ensure the air valve of the cooler outlet is closed;

4) Ensure the inlet valve of the cooler is opened;

5) Ensure the outlet valve of the cooler is completely opened;

6) Ensure the outlet valve of the cooler is opened largely, and confirm that the flow if the

cooling water is larger than 27m3 /h.

8.3.14.3 Motor water injection piping washing

1) Ensure the condensed water pump is in operation, the water temperature is less that 40

degrees Celsius, the water quality is qualified and no hydrazine is added in;

2) Check whether the water injection dual valve is closed or not;

3) Check whether the water injection valve and the acicular valve are closed or not;

4) Check whether the water injection tube is dismantle d or not;

5) ensure the water injection main valve is opened;

6) Ensure the water drain valve of the water injection main tube and the water drain valve of

the strainer are closed after the clean water is continuously discharged;

7) 7) Ensure the water injection valve and the acicular valve are ajar, and

the water injection valve is closed after the clean water is discharged from water injection

tube.

8.3.14.4 Water injection of the boiler water pump

1) The water injection of the boiler water pump should be carried out the boiler is filled with

water;

2) Check whether the check valve of the boiler water pump outlet and the bypass valve of

which are closed or not;

3) Ensure the high pressure side drainage valve of the cooler;

4) Ensure the pump inlet and outlet differential manometer is in a good condition and open




the isolation valve of the pump;

5) Ensure the water injection valve and the dual valve is opened;

6) Ensure the acicular valve controls the water injection flow to be less than or equal to

2.5L/min;

7) Check whether the high pressure side drainage valve of the cooler

continuously discharges the water and the water is clean or not, and ensure the air

outlet valve is closed;

8) Ensure the acicular valve is turned down and the water injection is maintained;

9) When the boiler water pump is spot-turned, the dual valve, water injection valve and the

acicular valve are closed.

8.3.14.5 Boiler water pump spot turn

1) After the water injection is completed, the insulation resistance against earth of the motor

conductor indicated in the 1KV megameter should be more than five megohms;

2) The boiler should be filled to a water level which is 100mm more than drum water level;

3) Ensure the check valve of the boiler water pump outlet is locally opened;

4) Ensure the boiler water pump is stopped after having been started for five seconds, and

20 minutes later, the boiler is started for five seconds and then is stopped, to drain the air

in the motor chamber.

5) The boiler water pump should be put into operation and the water injection should be

stopped after the boiler water pump having been spot turned for three

times and no abnormity having been found.

8.3.14.6 Boiler water pump startup conditions

1) The power supply of the motor is energized;

2) The control power supply is energized;

3) The motor is stopped for more than 20 minutes;

4) The cooling water flow of the motor is more than 27m3 /h;

5) The water temperature inside the motor is less than 55 degrees Celsius;




6) The outlet valve of the pump is unlocked;

7) The temperature difference of the boiler water and the pump (TDSH10) is less than 56

degrees Celsius;

8) The drum water level is more than 600mm;

9) The boiler water pump is spot-turned

8.3.14.7 Boiler water pump startup

1) The drum water level should be higher than +100mm before the first boiler water pump is

started;

2) The local/remote switch of the pump should be positioned remotely;

3) Single control: the boiler water pump can be singly started on DCS when the

startup conditions are met;

Confirm the pump to be started;

Select the pump on DCS and start the pump;

4) Group control startup;

Check whether the group control exits or not on DCS, (the green light is on);

Select the started pump on DCS ( the red light is on);

Start the pump with group control (the group control red light is on) and check whether

the pump is started or not;

5) Notes after startup;

Check whether the differential pressure of the outlet and inlet, current and the

motor water temperature of the operating pump are normal or not;

The interlock can be put into operation only after the standby pump is stopped for 20

minutes;

The pump should be stopped immediately if the motor temperature rises quickly and no

downtrend appears.

8.3.14.8 Boiler water pump hot reserve

The standby pump startup conditions comprise that:




1) The bypass valve HV*14 HV*15 of the check valve of the outlet is opened, and the pump

body is heated;

2) The upper interlock of the DCS has been put into operation.

8.3.14.9 Boiler water pump transfer

1) Group control transfer (on DCS);

a) Select the standby pump (lights on), and select the pump to be stopped (lights off);

b) Integrate the group control startup, and check whether the standby pump is started

or not and whether the pump to be stopped is stopped or not

c) The interlock automatically quits, and is put into operation again 20 minutes later.

2) Single transfer

a) Singly start the standby pump;

b) Ensure that the pump is normally started;

c) Stop the pump to be sopped;

d) Ensure that the pump is stopped and the current is reduced to zero, and 20 minutes

later the interlock switch is put into operation.

3) Automatic transfer

The group control is closed, the interlock is put into the standby pump, and the startup

conditions are complete; the standby pump would automatically be started if any of the

operating pump trips; the interlock quits, and can be put into operation again after 20

minutes.

8.3.14.10 The operation and maintenance of the boiler water pump

1) The normal temperature of the motor chamber should be 45 degrees Celsius, and an

alarm will be given at 60 degrees Celsius, and the pump will give an extreme alarm and

trips at 65 degrees Celsius.

2) The normal value of the differential pressure of the boiler water pump is more than 1.4

bar, and the differential pressure value when two pumps are in operation is 1.4 bar and a

boiler MFT action would be carried out when the differential pressure is less than or equal

to 1bar.




3) The temperature between the boiler water and the pump shell should be less than 50

degrees Celsius, and a high temperature difference alarm will be given at 56 degrees

Celsius.

4) The normal cooling water flow of the cooler is more than 27m3 /h, and when the cooling

water flow is less than or equal to m3 /h, a low cooling water flow alarm will be gave, and

20 seconds later the pump will trip.

5) The load of the boiler is less than or equal to 60 percent MCR when only one boil water

pump is in operation;

6) When the temperature of the standby pump motor chamber rises to approximately 55

degrees Celsius, the standby pump should be started and put into use, and should be

stopped after the temperature is reduced.

7) The attendant should check the leakage of the boiler water pump high pressure

side; when leakage is found, the attendant should report to the

chief attendant, and countermeasures should be taken immediately to prevent the

motor from burning loss.

8.3.14.11 Boiler water pump shutting down

1) Ensure the water temperature of the downcomer of the drum is 90 degrees Celsius, the

inner layer air valve of the drum is opened, and when the water

temperature of the downcomer of the drum is less than 70 degrees Celsius, two

boiler water pumps should

be shut down;

2) The cooling water flow should be maintained when the pump is stopped;

3) Boiler water pump that are stopped for a long period should be periodically

checked whether the motor are filled with water; ensure that the boiler water pump

operates for at least 10 minutes every two months, and should be started and operated

for 10 minutes every 15 days at the period of pressure maintenance.

4) Shutting down operation of the pump

a) Group control shutting down;

Select the group control shutting down order on DCS;

Check whether all operating pump are stopped or not and whether the current is

reduced to zero or not;

The outlet check valve should be closed.






b) Singly shutting down

Quit the boiler water pump interlock on DCS;

Select the pump to be stopped and stop it with single control;

Ensure that the pump is stopped, and the current is reduced to zero.

8.3.14.12 Boiler water pump operation in boiler acid cleaning

1) All boiler water pumps should be injected with water before acid cleaning

and water filling.

2) Only one boiler water pump should be in operation in acid cleaning, and the other two

pumps are isolated.

3) All cooler of the boiler water pump should be put into operation, and the cooling water

quantity should be more than 27m3 /h.

4) The water injection pressure should be kept higher than pressure of the drum by 6bar in

acid cleaning.

5) Continuous water injection should be carried out to the operation pump in acid cleaning

6) inject the water according to the operation; ensure that the injected water is

drained completely, and the water injection quantity should be maintained more than or

equal to

4.5L/min; the temperature of injection water should be less than 45 degrees Celsius.

7) Before adding the liquor to the boiler, the pump should be started and in operation.

8) Continuous water injection should be carried out to the isolated pumps.

9) The outlet check valve and bypass valve should be closed.

10) High pressure side drainage valve of the cooler should be closed.

11) Inject the water according to the operation; maintain the water injection quantity by

more than or equal to 4.5L/min after the air is completely drained; water injection

should be carried out continuously, and the water injection pressure should be higher

than the drum pressure by 6bar.

9 Periodic work, test and shifting of the boiler and relevant auxiliary equipment

NO. Projects Type Period Remarks




1 Oil gun torch Periodic test Once a week

2

Forced draft fan

lubricant station oil pump

Periodic shift Every half month

3

Induced draft fan

bearing cooling fan

Periodic shift Every half month

4

Flame check cooling fan

(DC)

Periodic test Once a week

5

Standby coal pulverizer

lubricant station oil pump

Periodic test Once a week

6 Boiler blowdown Periodic work Once a day

7

Boiler proper soot blowing Periodic work Once a day Part by

different tiem

periods and

stations8 Air preheater soot blowing Periodic work Every eight hours

9

Local water level

gauge washing

Periodic work Once a week

10

electromagnetic relief valve

blowdown

Periodic test Once a month

11

operational parameter

record

Periodic work Once a hour

12

Devices patrol and

inspection

Periodic work Every two hours

10 Accidents processing of boiler

10.1 Basic Principia of Accidents Processing

10.1.1 When the unit accidents occur, the operator on duty should quickly identify the cause of the

accidents to restrict further development of accidents and prevent the expansion of

accidents. When the accidents are confirmed to have direct threat on personal safety and

equipment, the risks of personal safety and equipment should be decisively eliminated. At the

same time attention should be paid to continued operation of non-fault equipment as far as

possible so as to meet the




need of system load.

10.1.2 The operator on duty should seek to ensure power supply of electricity system of the power

plant.

10.1.3 In order to accomplish the above tasks, the operator on duty must stick to his post and

focus his mind to ensure the normal operation of equipment, eliminate all abnormal situations and

correctly and fast implement orders given by superior officers.

10.1.4 When the unit has malfunction, the operator on duty generally should work according to the

following steps to eliminate failures.

10.1.5 Rapidly eliminate the risks on personal safety and equipment and the

equipment with malfunction should be immediately out of synchronization (or stopped) when

necessary.

10.1.6 Correct analysis and judgement should be done to indentify the nature, location and scope

of accidents and then proceed to treatment according to instrument indication, alarming signals of

CRT and alarm window and external Faults of the unit. At the same time attention should be paid

to continued operation of non-fault equipment.

10.1.7 Situation of each stage in failure removal should be reported to the shift supervisor as fast

as possible so as to timely take countermeasures to prevent the failure expansion.

10.1.8 If the failure is caused by failure of the system or other equipment, corresponding measures

should be taken to maintain the unit to operate with a certain parameters so as to make it possible

to quickly recover normal operation of the entire set of unit.

10.1.9 According to the unit operating characteristics, accidents caused in any part of the unit will

have a direct impact on the safe operation of the entire unit. Therefore, all posts should exchange

situations during malfunction occurance and closely coordinate with each other to rapidly treat with

the failure under the unified command of the shift supervisor and the chief supervisor.

10.1.10 The chief supervisor should be administered by the shift supervisor during failure removal,

and should rapidly participate in failure elimination and firstly report to the shift supervisor as much

as possible when the malfunction occurs. At the same time, the chief supervisor should report the

taken measures to the shift supervisor and comply with all correct commands

of the shift supervisor.

10.1.11 During accident treatment, the shift supervisor is entitled to call on

all concerned personnel in the power to be on-site to assist to deal with the failure and

meanwhile, all relevant leaders must quickly hurry to the spot to help deal with the failure and

give necessary instructions






to operators (all these instructions should be issued by the shift supervisor in general expect for

special circumstances.)

10.1.12 Careful analysis, correct judgement, decisive manipulation and rapid action

should be necessary during failure treatment. In addition, impatience and panic should be

avoided, otherwise the failure will not be eliminated, but becomes expansive and

difficult to handle. The operator should repeat the received order when in treatment of

malfunctions and make it clear until get the order understood, and promptly make reports to those

who give the orders after having fulfilled the orders.

10.1.13 The operator must promptly report to the chief supervisor the unfamiliar malfunctions so

as to jointly study the causes and deal with the failure. When no specified malfunctions is included

in the manual, the operator should analyze and judge the causes with his own

knowledge, initiatively take countermeasures and report the failure condition to the superiors at all

levels.

10.1.14 The operator on duty is not allowed to leave his post freely during the time when the unit

malfunctions occurs until resuming to the normal condition. When the failure occurs at the shifting

time, the shift should be deferred and the shift person should continue to work with the assistance

of the relieve person to jointly deal with failure. The shift can only be done until failure is removed

and commond is received from the shift supervior.

10.1.15 Forbidden and eliminate the case that people who do not involve in the failure removal

stay at the place where failure occurs.

10.1.16 After the acccidents have been disposed, personnel at all posts should truthfully record in

detail the unit failure situation, occurance time, place and the process of

disposal on the registering book for shift respectively, and analyze the failure treatment on

the meeting after shift

so as to sum up experience and draw a lesson.

10.1.17 The shift supervisor and chief supervisor are not allowed to leave the control room at the

same time when the system failure occurs.

10.2 Boiler Emergency Shutdown

10.2.1 If any one of the following conditions is met, the MFT starts and the boiler automatically

stops:

10.2.1.1 The power failure of control system or abnormality of pressure for

controlling air is delayed for three seconds.

10.2.1.2 No induced draft fan is running






10.2.1.3 No forced draft fan is running

10.2.1.4 No air heater is running

10.2.1.5 Total air flow is below the minimum value (two seconds’delay in action)

10.2.1.6 Water temperature is too high (from TE 052I) with no exhaust sustained for above six

seconds or the water temperature is not high (from TE 052I) but the furnace

temperature is abnormal or too high (above six seconds’delay)

10.2.1.7 Steam discharge is undone (six seconds’ delay in action)

10.2.1.8 Drum level is too low (two seconds’ delay)

10.2.1.9 Drum level is too high (60 seconds’ delay) and 12% higher than the MCR flow.

10.2.1.10 Non-biler water circulating pump is in operation and the tripping action is delayed two

seconds.

10.2.1.11 Furnace pressure is too low or too high

10.2.1.12 Air cooling pressure of the flame detector is too low (600 seconds’ delay)

10.2.1.13 Flame detector breaks down; the last burner is delayed 15 seconds after the purge and

storage are re-set or the entire detector breaks down.

10.2.1.14 Superheated steam pressure is too high (pressure switch) with six seconds’ delay in

action.

10.2.1.15 The air temperature of electric precipitation entrance is too high with this action delayed

two seconds.

10.2.1.16 The steam flow after the reflux starts is still greater than x1% before the reflux and only

one circulating pump is in operation after T1.

10.2.1.17 The steam flow when the reflux starts is still greater than x1% before the reflux and only

one circulating pump is in operation after t seconds (T1 + T2).

10.2.1.18 Only one emergency stop button is used.

10.2.1.19 When the reflux starts, control loop of at least one raw coal feeder is in a manual state.

10.2.2 The following processing procedures should be automatically done after the MFT action,

otherwise human intervention should be adopted:




10.2.2.1 Cut off all fuel;

10.2.2.2 Pulverizer coal feeder and oil gun torch fully stop;

10.2.2.3 Fuel oil inlet solenoid valve is closed;

10.2.2.4 Pulverizing system fully stop;

10.2.2.5 Frontwall balance wind baffle plate and backwall balance wind baffle plate: A is 100%, B

is 20% and C is 0%.

10.2.2.6 Turbine trips and generator runs out of synchronization;

10.2.2.7 High voltage bypass and low voltage bypass starts up automatically.

10.2.3 Manual processing methods after MFT action

10.2.3.1 Confirm that the boiler main stop valve FSRUV04A automatically closes, or the manual

control should be employed to close the boiler main stop valve.

10.2.3.2 Confirm that the high voltage bypass rapidly starts up and automatically resumes to a

certain opening so as to maintain the pressure of 15 bar of the reheater. If the the high voltage

bypass does not start up, manual control should be applied to the hight voltage bypass so as to

make it start. The high voltage bypass is then returned to a proper opening after 15 seconds and

put in automatic control after the pressure of the reheater is set at 15 bar.

10.2.3.3 Attention should be paid to the drum water level. If the water level is too high, continuous

relief valve and stable relief valve can coordinate for water level regulation.

10.2.3.4 Attention should be paid to that the operation of the boiler water pump should be normal

and immediately suspended when there are abnormalities such as the shock, pressure difference,

etc.

10.2.3.5 Confirm that after the secondary air baffle plates are locked for one minute, all secondary

air baffle plates of the oil fuel burner should be in an opened state and the total air volume should

be maintained at 30% MCR; and the purge procedure (for 5 minutes) of the boiler framework is

then done.

10.2.3.6 If the reason of MFT action can not be identified or eliminated at the moment, the decision

of stopping the primary air fan, forced draft fan and induced draft fan should be promptly made and

the inlet baffle plates and the outlet baffle plates should be closed so as to maintain the boiler in a

standly heat state.




10.2.3.7 Keep the air preheater, flame scanning cooling fan and cooling fan of oil gun torch

running.

10.2.3.8 If the failure can be eliminated in a short time, the shift supervior after having received the

order of starting up the units should started up the units as soon as possible according to the boiler

stoppage duration and corresponding conditions so as to meet the demand of system load.

10.2.3.9 If the reason of MFT action is caused by the the primary air fan, forced

draft fan or induced draft fan, the boiler framework should be thoroughly purged

before re-ignition; all the primary air pipelines should be purged for 20 minutes before the

pulverized coal is supplied.

10.2.4 Emergency boiler shutdown

10.2.4.1 Any one of the following situations occurs, the “emergency boiler shutdown button”

should be immediately pressed for boiler shutdown.

a) When in low-load operation, the combustion instability occurs and the boiler framework

pressure substantially fluctuates around ± 5mbar and the steam flow rapidly declines.

b) The safety valve has failure to operate even when boiler pressure exceeds the working

value of safety valve; meanwhile, the high voltage bypass valve and the

low voltage bypass valve and the non-atmospheric relief valve of reheater

are unable to start up automatically or manually.

c) When blast of the main feed water piping, main steam piping, water wall, economizer,

superheater and reheater occurs and endangers adjacent pipings.

d) When all the boiler water level gauges are damaged and unable to monitor water level.

e) When the boiler is overfed with water with the water level higher than +25 mm and MFT

has failure to operate.

f) When the boiler is short of water with the water level lower than -600 mm and MFT has

failure to operate.

g) When the combustibles reburn in the gas dust so that the flue gas temperature rises to

above 200℃ in an abnormal state.

h) When the first and secondary spray attemperators all have failure and

the steam temperature has drastic change and can not be controlled.

10.2.4.2 Treatment methods of “emergency boiler shutdown” are the same as that of “automatic






boiler shutdown”.

10.3 Shutdown Application of Boiler

If one of the following cases is met, one should ask for approval of the factory

director in charge and do the boiler shutdown in a normal manner after having received the

order from the shift supervisor:

10.3.1 When pressure retaining parts which have leakage are still able to operate.

10.3.2 When the heating surface of boiler has been scorched and normal operation can not be

maintained even some measures have been taken to deal with it.

10.3.3 When the quality of feed water or steam of the boiler has seriously worsened and normal

operation can not be maintained even efforts have been made for adjustment and treatment.

10.3.4 When the metal wall temperature of the heat absorption area has extremely exceeds the

allowable value and normal operation can not be resumed even great efforts have been made for

treatment.

10.3.5 When the enclosed cooling water source of cooler of the boiler water pump

motor is interrupted and the alternative water source can not be resumed immediately.

10.3.6 When the high voltage bypass after tripping can not be closed.

10.3.7 When the safety valve has defects, failure to operate or can not be reseated.

10.3.8 When main motors of two air preheaters have failure and can not be resumed in a short

time.

10.3.9 When the gas dust has serious deposition of ash and is unable to

maintain normal operation after much effort.

10.3.10 When chief supervisory meter has failure and is unable to maintain normal operation and

can not be resumed in a short time.

10.3.11 When the two electric precipitators have failure and normal operation

can not be maintained after much effort.

10.4 Boiler Abnormal Operation Parameter

10.4.1 High temperature of main steam

10.4.1.1 Faults




a) Alarm is given due to “high temperature of main steam” (> 560℃);

b) If the heat absorption surface has leakage or explosion, steam temperature of various

sections before the breaking point drops and temperature of various working substances

after the breaking point increases.

10.4.1.2 Causes

a) The high pressure heater is out of operation and feed water temperature drops.

b)

The attemperating water system has failure or automatic malfunction th t

the

attemperating water flow reduces abnormally.

c)

Decrease of feed water pressure causes attemperating water flow reduction.

d)

Gas duct in the rear part reburns.

e)

Coal quality or combustion operating condition change.

f)

The flame center of boiler framework moves upwards.

g)

The heating surface has leakage and blast.

h)

Air flow is too much.

i)

Coal pulverizing system starts up.

j)

The boiler framework is scorched.

10.4.1.3 Countermeasures

a) When water supply system and spray attemperating water system

have failure automatically, manual adjustment should be immediately adopted. The

systems are then put into operation after the steam temperature becomes stable.

b) When in soot blowing of boiler framework, the openings of the upper tertiary air baffle

plate and the lower tertiary air baffle plate should be regulated for

adjustment flame center. The openings of secondary air baffle plates of three rows of A,

B and C should be regulated when neccessary.

c) Adjust the air flow and maintain the best excess air coefficient. (That is, to maintain the

best oxygen content value).

d) Increase attemperating water flow and pay attention to relation between the drum




pressure and the main feed water piping pressure.

e) The high steam temperature is caused by leakage or blast of heating

surface, or the reburning of combustibles in gas duct and should be dealt with

according to the relevant provisions.

f) If the temperature of main steam keeps increasing after the above treatment measures

have been taken, the turbine should be adjust together with the boiler

according to relevant provisions. But the temperature of main steam should not

exceed the limit and the unit load can not drop too much.

g) When the temperature of main steam stop valve in front of the turbine reaches 566℃, the

turbine trip should be done.

10.4.2 Low temperature of main steam

10.4.2.1 Faults

a) Alarm is given due to “low temperature of main steam” (< 560℃);

b) Steam temperature of various sections drops and the steam piping has impact in severe

case.

10.4.2.2 Causes

a) The attemperating water system has failure or automatic malfunction so

that the attemperating water flow increases abnormally.

b) The feed water pressure increases abruptly so that the attemperating

water flow increases.

c) Coal pulverizing system is out of operation.

d) Fouling of heating surface area.


a) When the automatic adjustment is abnormal, manual adjustment should be immediately

adopted so as to resume the normal operation.

b) Reduce the attemperating water volume; close motor-operated valve if the

governor valve has serious leakage and then close hand-operated stop

valve in case of emergency.




c) Soot blowing should be done to the superheater.

d) Timely regulate the air volume and lift the flame center.

e) If the temperature of main steam keeps decreasing after the above treatment measures

have been taken, treatment should then be done according to the turbine manual (when

the steam temperature drops to 510℃, the load of turbine should be properly reduced);

turbine trip should be done when the temperature of main steam drops to 450℃.

10.4.3 High temperature of reheated steam

10.4.3.1 Faults

a) Alarm is given due to “high temperature of reheated steam” (< 560℃);

b) Temperature at various points in the reheating system increases.

c) If the heating surface has leakage or explosion, temperature at various points before the

breaking point drops and temperature at various points after the

breaking point increases.

10.4.3.2 Causes

a) The attemperating water system of reheater has automatic malfunction so

that the attemperating water flow reduces;

b) Air flow is too much;

c) The flame center moves upwards;

d) The heating surface of water wall is not clean;

e) Fuel or fuel operating condition has changed;

f) The coal pulverizing system starts up.


a) When the attemperating system of reheater has failure automatically, manual adjustment

should be immediately adopted so as to ensure the reheated steam is in

a normal condition.

b) If the air volume is too much, the air volume should be properly

reduced and the combustion should be adjusted.




c) Strengthen soot blowing of the heating surface of water wall and reduce temperture of

main steam when necessary.

d) If the leakage and explosion of heating surface of the reheater causes the

reheated steam temperature to increase, measures of temperature reduction

should be taken immediatedly and treatment should be done according to

corrsesponding provisions as well.

e) The openings of the upper tertiary air baffle plate and the lower tertiary air baffle plate

should be regulated so as to lower the flame center. The openings of secondary air baffle

plates of three rows of A, B and C should be regulated when neccessary.

f) If the temperature of reheated main steam keeps increasing after the above measures of

temperature reduction have been taken, the turbine should be adjusted together with the

boiler according to relevant provisions.

g) When the temperature of reheated main steam increases to 566℃, the turbine trip should

be done.

10.4.4 Low temperature of reheated steam

10.4.4.1 Faults

a) Alarm is given due to “low temperature of reheated steam” (< 520℃);

b) Temperature at various points in the reheater system decreases.

c) If the heating surface has leakage or explosion, temperature at various points before the

breaking point drops and temperature at various points after the

breaking point increases.

10.4.4.2 Causes

a) The attemperating water adjustment of reheater has malfunctions so

that the attemperating water flow of the reheater increases;

b) The flame kernel moves downwards;

c) The unit load is too low;

d) Fuel or fuel operating condition has changed;

e) The main steam stop valve of intermediate-pressure cylinder or high-pressure exhaust

check valve has failure on a single side so that the steam flow deviation between the left




side and the right side is caused.

f) Safety valve of reheater outlet operates or the outlet section has leakage or explosion.

g) The coal pulverizing system shuts down.

h) Fouling of heating surface area of reheater..


a) When the automatic adjustment of attemperating water of reheater is abnormal, manual

adjustment should be immediately adopted so as to resume the normal operation. The

motor-operated valve should be closed when necessary and the hand-operated

valve should then be closed if the leak volume is too much.

b) If the air volume is too much, the air volume should be properly increased.

c) Regulate the openings of secondary air baffle plates of three rows of A, B and C and the

openings of the upper tertiary air baffle plate and the lower tertiary air baffle plate; lift the

position of flame center.

d) Strengthen soot blowing of the heating surface of the reheater.

e) The turbine load should be reduced according to provisions when the reheated steam

temperature continues to decrease to 510℃.

f) When the temperature of reheated steam continues to decrease to 450℃, the turbine trip

should be done.

10.5 Load Rejection of Unit

Under one of the following cases, the boiler will automatically reduce load.

10.5.1 If one set of induced draft fan trips, the load reduces to 50% MCR.

10.5.2 If one set of forced draft fan trips, the load reduces to 50% MCR.

10.5.3 If one set of primary fan trips, the load reduces to 50% MCR.

10.5.4 If one set of air preheater trips, the load reduces to 50% MCR.

10.5.5 If one set of boiler water pump trips and the standby water pump can not be interlocked, the

load reduces to 60% MCR.

10.5.6 If one set of feedwater pump trips and the standby pump can not be interlocked, the load




reduces to 60% MCR.

10.5.7 If the turbine trips, the boiler load reduces to 70% MCR.

10.5.8 If operating with auxiliary power, the boiler load reduces to 70% MCR.

10.6 Auxiliary Power Supply Interruption

10.6.1 Faults

10.6.1.1 Turbine trips and the boiler MFT action is done.

10.6.1.2 All running machines trip.

10.6.1.3 Each motor-operated valve stays at the place before power interruption.

10.6.1.4 Pressure of main steam, steam temperature and flow all decrease.

10.6.2 Countermeasures

10.6.2.1 Ensure that DC fan of the flame scanner is in operation and DC motor of air preheater

starts up.

10.6.2.2 Ensure that the TV water level gauge and flame TV of boiler framework are in operation.

10.6.2.3 Check and ensure that emergency drain three-way valve FV003 of boiler water

pump should automatically open and outlet valve of boiler water pump should be closed by hand

when the temperature of motor chamber of boiler water pump keeps on a rise.

10.6.2.4 The seal fan should starts up after the diesel-engine generator operates.

10.6.2.5 If the boiler is treated with soot blowing when auxiliary power interrupts,

immediate maintenance should be done and the soot blowing gun should be withdrawn.

10.6.2.6 The following steps should be done after the power supply is restored.

a) Make up water for the drum to the level of -100mm.

b) Start up the boiler water pump after the closed cooling water system resumes normal

operation.

c) Start up the main motor of air preheater.

d) Start up the AC cooling fan of flame scanner and stop the DC cooling fan

and then conduct the “interlocking”.




e) Start up the cooling fan of oil gun torch and conduct the “interlocking”.

f) Check and ensure that vaious motor-operated valves and regulating

valves of attemperating water are at the closing position; open the

recirculation valve of economizer.

g) Start up the lubricating oil system of coal mill.

10.6.2.7 Confirm emergency water tanks and supply water to following equipment

when the closed cooling water system interrupts.

a) Supply low-pressure cooling water to boiler water pump.

b) Supply cooling water to bearings of auxiliary equipment.

c) Supply cooling water to various oil coolers.

10.7 Control&Instrument and Apparatus Power Supply Interruption

10.7.1 Faults

10.7.1.1 General power of thermal regulator and instrument lose.

10.7.1.2 After the general power loss alarm signal of thermal regulator and instrument is given, the

power indicator of instrument turns off and the alarm is warning.

10.7.1.3 Survey meters and digital instruments have failure to display. Transmitter of automatic

control device loses power; the indicator turns off; relevant meters indicate zero and automatic

device has failure.

10.7.1.4 The secondary instrument instruction disorders on CRT graphic display.

10.7.1.5 Automatic protection limit device has power failure and the limit

protection has malfunction; the regulator (regulating device) has power failure and

automatically shuts down when in automatic operation.

10.7.1.6 Remote control of equipment on CRT graphic display has failure and the water level can

not be controlled.

10.7.1.7 The rotating speed of coal feeder indicates zero.

10.7.1.8 Unit operation is instable or even has fire-off and tripping.

10.7.2 Causes




10.7.2.1 Electrical system or power bus has failure.

10.7.2.2 Switch or knife switch has failure and standby power fails to do automatic operation.

10.7.2.3 UPS power loses.


10.7.3.1 If boiler has not fired off and the unit has not tripped when the thermal

regulator and instruments lose power, various control equipment and systems should be

switched to manual control and stably operate in the original operating condition.

Strengthen the supervision and inspection of instruments on the spot and ensure the

unit stable load as much as possible. If operation of corresponding valves and baffles is

required, the manual operation can only be done after the contact work inside and outside the

control room is well done.

10.7.3.2 Ensure the boiler framework stable combustion, supervise the primary meters, strengthen

contact and emphasize on operation analysis referring to other relevant parameters without blind

operation. Send personnel to monitor all water levels and make sure that the water

levels are controlled in a normal range and strictly prevent accidents of overfeeding or short

supply of boiler and water impact of turbine.

10.7.3.3 Inform relevant personnel for thermal regulation and quickly restore control

power of instruments.

10.7.3.4 If the instrument power fails to timely be restored which threatens the

unit safety operation, report should be made to the shift supervisor and the instruments shall shut

down due

to failure.

10.7.3.5 If the protection is caused by loss of power of instruments or total power loss of boiler,

turbine thermal regulator and instruments has met the conditions of emergency

shutdown, treatment should be done according to emergency shutdown.

10.7.3.6 If the boiler has fire-off, treatment should be done according to provisions for fire-off.

10.7.3.7 Make reports to group chief and shift supervisor after the unit shuts down; reignite and

start up the unit in thermal condition according to instructions of the shift supervisor

after the thermal regulator and instrument are done with energization.

10.8 Fire Accident

10.8.1 Countermeasures for fire catching of the oil system.

10.8.1.1 If fire catching is found in the oil system, dry fire extinguisher or foam fire extinguisher






should be instantly adopted for fire-fighting and report should be made to the shift supervisor to

promptly notify the firefighters to extinguish fire.

10.8.1.2 If the fire has not yet threatened the unit operation, measures should be taken to prevent

fire spread and put it out as soon as possible.

10.8.1.3 Move away combustibles around the fire spot and cut off power supply of

electrical equipment on the spot.

10.8.1.4 Strengthen the operation supervision and prepare for shut-down.

10.8.1.5 Attention should be paid to that the fire shall not spread around the spot

and wetted fire-retardant materials should be covered around the equipment when necessary

(pay attention to the rotating parts of the unit). Report should be instantly made to the shift

supervisor for shutdown when the fire threatens the unit safety.

10.8.1.6 If the fire threatens the safety of main oil tank, emergency shutdown should be done; start

up the emergency oil relieve valve (ensuring the lubricating oil supply is not interrupted before the

turbine stops) when the rotating speed of turbine decreases.

10.8.2 Fire catching of pulverized coal pipeline

10.8.2.1 Causes

a) The primary air pipeline is worn and has pulverized coal leakage to the extent of heat

insulation and has spontaneous combustion and fire-catching.

b) The pulverized coal pipeline is blocked and is not cleared up in time.


a) Stop the corresponding coal pulverizing system and shut-off valve of coal mill outlet in

accordance with specific conditions and extinguish fire with foam or fire-fighting water.

b) When fire catching occurs due to incomplete block off of pulverized

coal pipeline, personnel for locomotive maintenance should be contacted for

purging of primary air pipeline and corresponding treatment.

10.8.3 Notice items of fire extinguishing

10.8.3.1 If clothes which are not immersed in kerosene, diesel, petrol and other oils and wooden

materials catch fire, foam fire extinguisher, water and sand should be employed for fire fighting.




10.8.3.2 If oil tanks or oil in other containers catches fire, oil should be discharged from the

emergency oil relieve valve and foam fire extinguisher or wetted raincloth could be used for fire

fighting.

10.8.3.3 If the energized equipment catches fire, fire fighting should be done after the electricity is

cut off; sand and foam fire extinguisher should not be used for fire fighting when the motor catches

fire.

10.8.3.4 If found fuming, the motor should be promptly stopped running and the shift supervisor

and chief supervisor should be informed of the situation.

10.8.3.5 Observe relevant provisions of Specification for Fire Protection of Electric Power

Installation during fire fighting.

10.9 Processing Inferior Quality of Water and Steam

10.9.1 Processing value of abnormal water quality of condensate

Processing value

Items

Standard

value Stage I Stage II Stage III

With mixed

bed

≤0.30

030~0.40

0.40~0.65

>0.65

Electric

conductivity

(S/cm) Without

mixed bed

≤0.20

0.20~0.35

0.35~0.60

>0.60

With mixed

bed

≤2.0

>2.0

>5.0

>20.0

Hardness

(mol/l)

Without

mixed bed

≈0

>2.0

-

-

Note: emergency shutdown should be done when sodium content in condensate is more than

400g/l. 10. 9.2 Processing value of abnormal water quality of boiler feedwater

Items Standard Processing value




value Stage I Stage I Stage I

Electric conductivity (S/cm) ≤0.30 030~0.40 0.40~0.65 >0.65

Dissolved oxygen (g/l) ≤7 >7 >20 -

pH(25℃)

8.8~9.3

<8.8 or >9.3

-

-

10.9.3 Processing value of abnormal water quality of boiler water

Processing value

Items

Standard

value Stage I Stage I Stage I

pH(25℃) 9~10 9~8.5 8.5~8.0 <8.0

Note: contents of chloridion and sodium, electric conductivity and alkalinity should

also be measured.

Definition of above processing values of three stages:

Processing value of Stage I: the possibility that corrosion, scaling and salt

deposition are caused by impurities may be existed and the standard value should be resumed

within 72 hours.

Processing value of Stage II: the possibility that corrosion, scaling and salt

deposition are caused by impurities is surely existed and the standard value should be resumed

within 24 hours.

Processing value of Stage III: the corrosion, scaling and salt deposition are forming in a fast

way and the boiler should be shut down within four hours.

During each stage of abnormal processing, if the standard value fails to be resumed within the

required time, processing method of a higher level should be employed and one of the methods to

restore the standard value of water quality is to operate under lower pressure.

10.9.4 Principles of processing for abnormal water steam quality of unit

10.9.4.1 Promptly inspect whether the sampling is representative or not, whether

the testing equipment is in normal condition and whether the test results are correct when the

water steam quality degrades. Comprehensively analyze the change of water and steam quality

in the system and make reports to the chief engineer for the situation after correct confirmation

and judgement and take measures to ensure that the standard value of the water steam quality is

surely resumed within the allowable time.






10.9.4.2 When each items of water steam quality reach the processing value of Stage I and the

possibility that corrosion, scaling and salt deposition are caused by impurities may be existed and

the standard value should be resumed within 72 hours.

10.9.4.3 When each items of water steam quality reach the processing value of Stage II and the

possibility that corrosion, scaling and salt deposition are caused by impurities is surely existed and

the standard value should be resumed within 24 hours.

10.9.4.4 When each items of water steam quality reach the processing value of Stage III and the

corrosion, scaling and salt deposition are forming in a fast way and the boiler should be shut down

within four hours if the water quality is still in bad condition.

10.9.4.5 One of the methods to restore the standard value of boiler water quality is to operate

under lower pressure.

10.9.4.6 During each stage of abnormal processing, if the standard value fails to be

resumed within the required time, processing method of a higher level should be employed.

10.10 Boiler Heating Surface Slagging Seriously

10.10.1 Faults

10.10.1.1 When the water wall is scorched, the temperature of main steam and reheated steam

will have an abnormal increase.

10.10.1.2 When the heating surfaces of the superheater and the reheater are

scorched, the temperature of main steam and reheated steam will have an abnormal decrease.

10.10.1.3 The flue gas temperature has an abnormal increase.

10.10.1.4 When the coke slag is shedding, much change will occurs in the boiler

framework pressure, which will impact the stability of combustion.

10.10.2 Causes

10.10.2.1 Low ash melting point in coal combustion;

10.10.2.2 Deflection of flame center during combustion;

10.10.2.3 Overload operation of the boiler for a long time.


10.10.3.1 Adjust the combustion operating condition and properly lower the flame center in order




not to cause deflection of the flame center;

10.10.3.2 Decrease the flue gas temperature deviation of boiler framework outlet and lower the

temperature of boiler framework outlet;

10.10.3.3 Properly strengthen the soot blowing;

10.10.3.4 Select coal with relatively high ash melting point and conduct according to

specific combustion measures of corresponding coal type when the coal type alternation is

unavailable;

10.10.3.5 Properly reduce the boiler operation load and strengthen the disturbance in the boiler;

10.10.3.6 Strengthen the monitoring for coking performance in the boiler.

10.11 Gas Duct Reburning

10.11.1 Faults

10.11.1.1 Flue gas pressure has a sharp increase in the gas dust;

10.11.1.2 Negative pressure in the gas dust decreases;

10.11.1.3 Flue gas exhausts in the clearance of valves and holes of the gas dust;

10.11.1.4 Fire alarm is given when the recombustion occurs in the air preheater.

10.11.2 Causes

10.11.2.1 Due to long-term application of coarse pulverized coal or improper ratio of air/coal, the

incompletely-burned pulverized coal deposits in the gas duct.

10.11.2.2 Improper operation and adjustment or long-term upward moving of the flame

center causes the incompletely-burned pulverized coal to enter the gas duct.

10.11.2.3 Feed pulverized coal in advance during the start-up.

10.11.2.4 Long-term operation under low load, relatively low temperature of boiler framework or

the relatively small excess air coefficient worsen the combustion and cause a

great deal of combustibles to burn in the gas dust.

10.11.2.5 No purging is done to the boiler framework according to provisions after boiler shutdown.


10.11.3.1 Adjust combustion when the abnormal increase of temperature is found in the gas duct

and instantly conduct the soot blowing with soot blowing gun in the duct.




10.11.3.2 Make reports to the shift supervisor and do the emergency boiler shutdown if abnormal

increase of temperature in the gas duct or flue gas still occurs after some measures have been

taken.

10.11.3.3 The primary air fan, forced draft fan and induced draft fan should be instantly stopped

after boiler shutdown and all the air valves and baffle plates should be closed for enclosement.

10.11.3.4 The following measures should be taken when the fire catching of preheater occurs:

a) Ask instructions from the shift supervisor and conduct the emergency boiler shutdown.

b) Stop all the primary air fans, forced draft fans, induced draft fans and steam air heaters.

c) Close the air baffle plate and flue gas baffle plates of the air preheater.

d) Open the inspection hole of the lower ash hopper of the air preheater.

e) Instantly put the fire-fighting water device of air preheater into operation for fire fighting.

f) Inspect the water discharge condition of ash hopper of air preheater and timely smoothen

the air hopper so as to prevent the ash hopper collapse.

g) The fire-fighting water supply can only be stopped after the fire completely extinguishes

and the flue gas temperature decreases to a normal value.

h) Water washing should be done to the air preheater if the ash deposition is serious and

the air preheater should be dried with the steam air heater after water washing.

10.11.3.5 Slowly and carefully open the inspection hole for inspection and start up the induced

draft fan only after no fire sources is ensured.

10.11.3.6 Ignition and start-up can only be done after the equipment is checked and ensured no

abnormality and the instruction from the shift supervisor is received.

10.12 Unit Trip

10.12.1 Faults

10.12.1.1 Main steam pressure is rapidly increased, high and low pressure bypass

valves are automatically and swiftly open.

10.12.1.2 Main steam flow is swiftly dropped, high and low pressure bypass valves return 15

seconds after opening.

10.12.1.3 Reheat steam pressure is rapidly increased and reheater exhaust valve is automatically




opened.

10.12.1.4 Water level of drum is low before it gets high.

10.12.1.5 Main steam temperature and reheat steam temperature tend to be high before it drops

low.

10.12.1.6 After turbine trips, if low pressure bypass functions abnormally or

is adjusted inappropriately, safety valve of reheater or of drum will start operating.

10.12.1.7 When main steam flow is under 420T/H with oil gun still unused, all coal feeders will trip

and boiler MFT will start operating.

10.12.1.8 When low pressure bypass fails and closes down, reheater exhaust valve

remains closed, boiler MFT will starts operating.


10.12.2.1 Boiler load is automatically dropped to 70%MCR, or make it happen by hand.

10.12.2.2 High and low pressure bypass valves should be swiftly opened or have it opened by

hand.

10.12.2.3 Make sure that exhaust valve of reheater is automatically opened, or open it by hand.

10.12.2.4 Before the oil gun is put into use, stabilize the load above 420T/H to avoid boiler MFT

operation.

10.12.2.5 When the number of oil gun put into use exceeds 4 according to rules, gradually stop the

pulverized coal feeder that has not yet been provided with oil guns and lower oil load to avoid

closing low pressure bypass because of low vacuum in turbine.

10.12.2.6 Properly lower main steam pressure fixed value.

10.12.2.7 When main steam pressure drops, place high pressure bypass under

automatic or manual position to avoid the tripping of boiler because of the closure of

high pressure bypass valve.

10.12.2.8 Attention should be paid to drum water level, when water feeding can

not work automatically, switch to manual regulation.

10.12.2.9 Maintain the superheat steam temperature and reheat steam temperature at above 500

DEG C, attention should be paid to desuperheater water to make sure that it is normal; if not,




control it manually.

10.12.2.10 If tripping of turbine can not be swiftly restored, boiler combustion

should be maintained and MFT operation be avoided.

10.13 Steam Drum Full Feeded

10.13.1 Faults

10.13.1.1 When “water level height” reaches +25mm, alarm should be sounded, but if 10 seconds

later, water level remains at the same level, operate MFT.

10.13.1.2 Water level of TV water level gauge and local water level gauge is too high to be seen.

10.13.1.3 Feedwater flow is abnormally greater than main steam flow.

10.13.1.4 Steam gas temperature is rapidly dropped, main throttle valve flange emits white vapor,

when it is serious, “water hammer” will take place as a result.

10.13.1.5 Superheat steam gas conductivity is high.

10.13.2 Causes

10.13.2.1 Feedwater automatic regulation fails to work;

10.13.2.2 Errors caused by falseness of water level indication or relaxing of

water level surveillance;

10.13.2.3 Boiler load is low and feedwater regulating valve leaks too much;

10.13.2.4 Load or steam pressure fluctuation is too great;

10.13.2.5 Sudden opening of high pressure bypass or operating of drum safety valve;

10.13.2.6 All furnace water pumps trip;

10.13.2.7 When water level is in the form of “default”, its setting value is too high;


10.13.3.1 When water level reach -75mm and high water level signal has been sent out, feedwater

regulating should be immediately switched to manual status and feedwater flow

should be diminished, if necessary, stable relief valve and continuous relief valve

should be coordinately regulated until drum water level returns to normal.

10.13.3.2 When feedwater regulating valve leaks too much, load should be increased properly, if




necessary to maintain normal water level.

10.13.3.3 When water regulation and meter indication are inaccurate, thermal engineering experts

should be immediately sent for.

10.13.3.4 During operation, surveillance of drum water level and checking of local

water level gauge should be reinforced, and mistakes should be avoided.

10.13.3.5 Desuperheater water should be disconnected according to steam temperature,

and drainage in superheater and main steam valve should be started.

10.13.3.6 After MFT is operated, address problems according to methods following the operation

of MFT.

10.13.3.7 After the above measures have been taken, if drum water level still rises to pass +25mm,

while MFT is still out of operation, the following emergency measures should be taken:

a) Press “emergency shut down” button;

b) Stop feed (water) pump and make sure that the recirculating valve of coal economizer

has been opened;

c) Make sure that main steam valve is closed;

d) Open all drains of superheater system and main steam drain of turbine as well;

e) Make sure that all desuperheater water valves have been closed;

f) Water discharging should be reinforced until drum water level is seeable;

g) When overflow has been ruled out and drum water level have returned to normal, boiler

will not be restarted until shift supervisor have agreed to do so;

10.14 Steam Drum Short Feeded

10.14.1 Faults

10.14.1.1 Water levels shown in TV and local water level gauges are too low to be seen.

10.14.1.2 “Drum water level” keeps dropping after alarm is sounded when it drops to -415mm, and

when it drops to -600mm, if 10 seconds after the “drumwater level record low” alarm have sounded,

it remains at the same level, MFT should be operated.

10.14.1.3 Feedwater flow is abnormally less than steam flow (the other way round is true of coal

economizer and water cooled wall leakage).




10.14.1.4 When water shortage is serious, pressure difference of furnace water pump is low and it

shakes.

10.14.2 Causes

10.14.2.1 Feed water control malfunction and feed (water) pump failure result in the decrease of

water allowance or water main pressure becoming too low.

10.14.2.2 Falseness of water level indication results in operation that is wrong.

10.14.2.3 Feed water line leaks too much.

10.14.2.4 Leakage and mis-operation of blow down valve or pollution discharge

contact is inappropriate.

10.14.2.5 Cracking of water wall tube or economizer tube.

10.14.2.6 Load fluctuation is too great.

10.14.2.7 Opening indication of feedwater-regulating valve fall short of actual opening.

10.14.2.8 Feedwater electrically operated valve mis-close or feedwater regulating valve panel falls

off.


10.14.3.1 When water level is (-415mm) with furnace water pump operating normally and alarm is

sounded, feedwater regulation should be immediately switched to manual status, and more water

should be pumped into boiler to return drum water level to a normal level.

10.14.3.2 All drainage operation should be stopped.

10.14.3.3 Attention should be paid to changes of main steam temperature in the process of water

inflow.

10.14.3.4 When the above measures have been taken, water level keep dropping to -600mm at

which MFT begins to operate in 10 seconds, if not, the following measures should be taken.

a) Press “emergency shut down” button

b) Stop the operation of furnace water pump, feed boiler with water when drum water level

is lower than visible water level. If regulating valve panel falls off, furnace water pump

should be immediately stopped, boiler be fully closed, electric unit be notified

to stop furnace water pump power supply, and at the same time, furnace water pump

should be




closed off and attention paid to drum wall temperature changes.

c) Reasons for water shortage should be identified and it should be properly solved, boiler

can not be restarted until orders to do so have been authorized by shift supervisor.

d) Water inflow time and speed of water-empty boiler should be decided by

director in charge who will issue the order.

10.15 Priming

10.15.1 Faults

10.15.1.1Drumwater level drastically fluctuates and water level inside water level gauge is unclear;

10.15.1.2 Feedwater self regulation is unsound;

10.15.1.3 Main steam temperature is dropped and steam conductivity is increased,

when it is serious, water slug will take place inside the main steam pipes.

10.15.2 Causes

10.15.2. Quality of feedwater or boiler water is unqualified;

10.15.2.2 Boiler load drastically drops or steam pressure drastically drops;

10.15.2.3 Oil entering into the steam system.


10.15.3.1 Report to shift supervisor, decrease and stabilize boiler load;

10.15.3.2 Open continuous relief valve, intensify stable relief valve, and lower the drum water level

to -50mm;

10.15.3.4 Chemist should be notified to stop adding drugs and increase boiler water laboratory

test.

10.16 High Furnace Pressure

10.16.1 Faults

10.16.1.1 “Furnace pressure high I value” alarm sounds;

10.16.1.2 Indication of furnace draft meter skews positively;

10.16.1.3 Fume is emitted from leaking zone of furnace;




10.16.1.4 When “furnace pressure high II value” alarm sounds, MFT will take place.

10.16.2 Causes

10.16.2.1 Force fan can not track and check in time after single induced fan fails and trips;

10.16.2.2Automatic device of furnace draft fails;

10.16.2.3 Suction guide and outlet damper of induced fan or smoke damper of gas

dust are mis-closed;

10.16.2.4 Combustion operation conditions deteriorate;

10.16.2.5 Pressure-bearing members inside furnace have been seriously burst.


10.16.3.1 Guide vane of induced fan should be switched to manual status and its opening should

be regulated to maintain the furnace negative pressure at a normal level;

10.16.3.2 Baffle plate that has been mis-closed should be restored to its original state in time;

10.16.3.3 When furnace pressure is high and MFT starts, problem should be addressed according

to relevant rules followed by the resolution of the operation of MFT.

10.17 Low Furnace Pressure

10.17.1 Faults

10.17.1.1 “Furnace pressure low” alarm sounds;

10.17.1.2 Indication of furnace pressure meter is increased in the direction of minus value;

10.17.1.3 When “furnace pressure low II value” alarm window sound the alarm, MFT

will take place.

10.17.2 Causes

10.17.2.1 Induced fan can not track and check in time when single force fan fails and trips;

10.17.2.2 Furnace draft self regulation fails to work;

10.17.2.3 Inlet movable vane and outlet damper of force fan and air duct baffle

plates are mis-closed;

10.17.2.4 Assisted wind regulating baffle plate fails or is mis-closed;




10.17.2.5 Boiler combustion working condition deteriorates or boiler fire goes out.

10.17.3 Countermeasures:

10.17.3.1 Flushing should be burned steadily by adding oil;

10.17.3.2 Regulate the opening of induced fan suction guide; maintain the furnace

draft at a normal level;

10.17.3.3 When draft self regulation fails, manual regulating should be switched on;

10.17.3.4 Return baffle that has been mis-closed to its original state;

10.17.3.5 When “furnace pressure low II value” alarm window sounds the alarm, operate MFT

according to MFT relevant rules.

10.18 Boiler Burning Out

10.18.1 Faults

10.18.1.1 Furnace pressure suddenly drops on a large scope, and primary and secondary wind

pressures drop simultaneously;

10.18.1.2 “Furnace losing flames” alarm sounds;

10.18.1.3 Flame detector shows no sigh of flame;

10.18.1.4 Flame check of burner at all levels all disappears;

10.18.1.5 MFT operates;

10.18.1.6 Steam temperature, steam pressure and main steam flow rapidly drop;

10.18.1.7 Water level goes down before it goes up.

10.18.2 Causes:

10.18.2.1 Failure and tripping of force fan, induced fan and primary fan, etc. or operation of boiler

tripping protection;

10.18.2.2 When load is low, mixture ratio of wind and coal is seriously maladjusted;

10.18.2.3 When load is low, coal quality become worse and coal powder become thick, resulting in

the deterioration of burning working condition;

10.18.2.4 Oil is not put in to stabilize burning when the combustion is unstable;




10.18.2.5 Operational manner of burner is inappropriate;

10.18.2.6 When load is low, flame is blown out by furnace soot-blowing and water wall tube blast

or furnace draft is too great;

10.18.2.7 Water wall does not soot-blow, resulting in the falling of coke on a large acreage;

10.18.2.8 Oil system fails or oil-receiving electromagnetic valve is mis-closed when oil is burning;

10.18.2.9 House supply interrupts or MFT mis-operate.

10.18.3 Countermeasures:

10.18.3.1 Problems should be addressed according to relevant rules followed by the resolution of

the operation of MFT;

10.18.3.2 After causes are identified and removed, start induced and force fan with over 30% that

of air volume blowing furnace for 5 minutes, after that, reignite the furnace;

10.18.3.3 After fire is extinguished, the lifting of fire-extinguishing protection is banned and igniting

by deflagration is adopted.

10.19 Fuel Trip

10.19.1 Faults

10.19.1.1 Send out signal alarm to prompt ‘total loss of fuels’.

10.19.1.2 MFT happens to the boil.

10.19.1.3 All pulverizing systems trip and fuel oil supply is stopped.

10.19.1.4 No flame is shown in flame scanner of the furnace.

10.19.2 Causes

10.19.2.1 Coal in all coal silos is run out of.

10.19.2.2 All pulverizing systems trip.

10.19.2.3 Trouble happens to oil system during combustion or oil intake electromagnetic valve is

closed by mistake.


10.19.3.1 Eliminate the trouble according to MFT troubleshooting.




10.19.3.2 Find out the reason and recover operation as soon as possible.

10.20 Water Wall Tubes Txplosion

10.20.1 Faults

10.20.1.1 Steam pressure is down and water level in drum is dropped.

10.20.1.2 Negative pressure in furnace is reduced or turns to positive pressure.

10.20.1.3 The opening of baffle plates at the entrance to the induced draft fan is

abnormally increased.

10.20.1.4 Smoke comes out from the part where the sealing is not good in the furnace.

10.20.1.5 Steam ejection sound or explosion is heard from the furnace.

10.20.1.6 Water supply is abnormally larger than the steam flow.

10.20.1.7 The combustion is not stable and even may go out.

10.20.1.8 The flue temperature is dropped.

10.20.2 Causes

10.20.2.1 Poor quality of furnace water, which causes serious scale formation in pipelines.

10.20.2.2 The entrance orifice of water wall is blocked, which causes bad water circulation.

10.20.2.3 Serious coking in water wall, which causes uneven heat exposure.

10.20.2.4 Flame deflection, which causes uneven heat exposure in local water wall.

10.20.2.5 Water wall is damaged by large dropping lump coke.

10.20.2.6 Bad welding of water walls.

10.20.2.7 Serious sulfur corrosion.


10.20.3.1 If there is leakage happening to water wall but the water in the drum can be kept at a

normal level, short run operation in proper reduced load is permissible, but the chief attendant

should inform a factory director and ask for arrangement of boiler shut down which should be done

according to regular shut down procedures.

10.20.3.2 If the water wall is seriously damaged and the water in steam drum is not kept at a




normal level, the following measurements should be conducted.

10.20.3.3 Press ‘emergency shut down’ to stop the furnace quickly.

10.20.3.4 After the boiler is shut down, the induced draft fan should be kept

running and the furnace kept at a negative pressure. Stop the induced draft fan and change

the ventilation into natural ventilation when it is considered to be proper and keep the furnace at

a negative pressure

to emit flue and steam inside.

10.20.3.5 Continue supplying water to the furnace to maintain the water level of the drum; close

static-row and link-row motor-operated valve and hand-operated valve.

10.20.3.6 If the leakage of the water wall is extremely serious, and the water level in the drum can

not be kept after the furnace is stopped, the furnace water pump and feed water pump should be

stopped as well as recirculation valve of economizer.

10.20.3.7 The economizer should be received enough care and ashes

deposited in the economizer and the ash hopper of the air preheater should be

cleared up timely to prevent accidents of ash hopper and flue duct collapse caused by ash

deposit.

10.21 Economizer Tubes Explosion

10.21.1 Faults

10.21.1.1 Water level in drum is dropped.


10.21.1.3 Abnormal noise is heard at economizer part.

10.21.1.4 Ash hopper at the lower part of economizer is blocked by wet ash or ash water is leaked

from the ash hopper.

10.21.1.5 Flue temperature at the water leakage side is dropped.

10.21.1.6 There exists great difference of flue temperature at A side and B side of the entrance of

the air preheater.

10.21.1.7 The opening of baffle plates at the entrance to the induced draft fan is increased.

10.21.2 Causes

10.21.2.1 Poor quality of feed water, which causes serious scale formation in pipelines and to burn

tube.






10.21.2.2 It is worn by flying ash.

10.21.2.3 The recirculation valve of economizer is not operated according to provisions in boiler

starting or shutdown.

10.21.2.4 The tube is blocked when installation or maintenance.

10.21.2.5 Poor quality of tube or welding.


10.21.3.1 Increase water supply to keep the water level in the drum.

10.21.3.2 Operate it at a lower load and pressure and ask for factory director to decide the boiler

shut down time.

10.21.3.3 If the water level is not kept at a normal level after water supply increasing, stop the

boiler immediately with the approval of the chief attendant.

10.21.3.4 Try to keep the water level in drum as possible after the boiler shut down and close

continuous drainage valve and regular drainage valve, hand-operated valve and

recirculation valve of economizer.




deposit.

10.22 Superheater Tubes Explosion

10.22.1 Faults

10.22.1.1 Main steam pressure is dropped.


10.22.1.3 The negative pressure in the furnace turns positive and pressure in

flue duct is increased; steam is ejected from the part where the sealing is not good in the flue

tube.

10.22.1.4 Abnormal noise is heard at the leakage of superheater.

10.22.1.5 Flue temperature at the leakage side is dropped.

10.22.1.6 If roof tube, wall enclosure tube or low over leakage cause high over and medium over

steam temperature rising, and if the medium over and high over leak, the main steam temperature

rises.






10.22.1.7 Large steam temperature difference between the two sides.



10.22.2 Causes

10.22.2.1 Steam quality is deteriorated in the long run and scale formation in the tube causes over

heat on the tube wall.

10.22.2.2 Over heat or coking happens frequently in superheater.

10.22.2.3 It is seriously worn by flying ash.

10.22.2.4 Recombustion happens to some section of superheater.

10.22.2.5 Ash gun is wrongly installed or trouble comes up during operation and the gun is broken.

10.22.2.6 The tube is not qualified or the welding quality is poor.


10.22.3.1 When the over heater tube leaks, reduce load and pressure for operation and ask for

factory director to arrange to shut down the boiler.

10.22.3.2 If the superheater tube is seriously damaged, it should prevent the worsening of any

accident.




a negative pressure





deposit.

10.23 Reheater Tubes Explosion

10.23.1 Faults

10.23.1.1 The pressure at the outlet of reheater is dropped.

10.23.1.2 Main steam flow is increased.






10.23.1.3 Abnormal noise is heard nearby the reheater and when explosion, the negative pressure

in the furnace turns to positive and even steam or flue is ejected from the part where the sealing is

not good in the furnace or flue duct in serious case.



10.23.1.5 The steam temperature difference at the two sides of the reheater is large

and the temperature at the trouble side rises.

10.23.2 Causes

10.23.2.1 The steam quality is poor, which causes scale formation inside or maintenance of the

furnace after shutdown is done improperly, which corrodes the reheater tube.

10.23.2.3 It is worn by flying ash.

10.23.2.4 Poor quality of tube or welding.

10.23.2.5 The furnace temperature is not controlled strictly during operation and steam supplying

protection to the reheater is not sufficient during starting and shutdown.


10.23.3.1 If the reheater tube is not seriously damaged, operate it in a lower load and ask for the

factory director to arrange boiler shut down.

10.23.3.2 If the reheater tube is seriously damaged, do emergency shutdown after consent of the

chief attendant.




a negative pressure


10.24 The Break of Steam Pipes or Feedwater Pipes Outside the Boiler

10.24.1 Faults

10.24.1.1 Humility, water seepage or water leakage or steam leakage in damaged part. And even

leakage noise is heard.

10.24.1.2 Loud noise is heard when the pipe is explodes and steam and water are ejected and

supports and hangers may be damaged.




10.24.1.3 Steam or feed water pressure and the flow change are abnormal.

10.24.2 Causes

10.24.2.1 Poor material quality and unqualified fabrication, installation and welding, which affect

free expansion.

10.24.2.2 Long run operation under over pressure and over heat conditions.

Local wall of wearable parts (such as parts near elbow and porous plate) get thin, which lower

metal strength.

10.24.2.3 Pipe heating and water drainage are not sufficient during boiler ignition process, which

causes serious water impact.

10.24.2.4 Unqualified feed water quality, which causes pipe wall corrosion.

10.24.2.5 Dramatic changes of media flow, temperature and pressure happen during operation,

which causes fatigue and damage to the duct.


10.24.3.1 If the pipe is not severely damaged and is capable of supporting the normal operation

and will not worsen the troubles:

1) Adjust various parameters of the boiler, properly reduces the load to keep the normal operation

and report to chief attendant and apply for boiler shutdown.

2) Provide security measurement around the damaged part and prevent steam or

water from hurting personnel.

3) Pay close attention to the damaged parts and precast any accident that may happen.

10.24.3.2 Immediately stop the boiler in any emergency case that the severely damaged pipe or

trouble may cause accident.

10.24.3.3 Separate the damaged pipe section from the system as soon as possible after the boiler

shut down.

10.25 High Steam Drum Pressure

10.25.1 Faults

10.25.1.1 High pressure indicated in the pressure gauge of the drum.

10.25.1.2 High pressure indicated in superheat steam pressure gauge. Alarm window is lighted

and alarm is sounded.




10.25.1.3 When the superheat steam pressure is up to 18.5MPa, the high pressure bypass valve

and the low pressure bypass valve of the turbine are automatically opened (not been provided

yet).

10.25.1..4 When the superheat steam pressure is up to 2.05MPa, the electromagnetic

release valve automatically opens.

10.25.1..5 When the superheat steam pressure is up to 2.25MPa, the safety valve at the outlet of

superheater starts to work.

10.25.1..6 When the superheat steam pressure is up to 20.62MPa, the safety valve of the drum

starts to work.

10.25.1.7 After the electromagnetic release valve or the safety valve starts to work, the water level

in the drum first goes up and then drops.

10.25.2 Causes

10.25.2.1 The load is declined abruptly.

10.25.2.2 The safety valve fails to move.

10.25.2..3 The first valve of the electromagnetic release valve fails to open or the electromagnetic

release valve has not been shifted to automatic status.

10.25.2.4 Coal feeding controller (automatic combustion control) of the boiler is not dislocated or

the turbine speed regulating system fails.

10.25.2.5 The adding of high pressure bypass and the low pressure bypass is not successful.

10.25.2.6 Pulverizing system works at an abnormal status.

10.25.2.7 Automatic control system fails.


10.25.3.1Immediately take depressurization measurements:

a) Reduce coal feeder rotation speed and add oils for facilitating combustion according to

the combustion situation in the furnace. Stop the pulverizing system if necessary.

b) Open high pressure bypass valve and low pressure bypass valve of the turbine.

c) Manually open electromagnetic release valve.




10.25.3.2 Shift the operation mode of CCS coordination control system to boiler basic mode.

10.25.3.3 When the pressure in drum surpasses the safety valve working pressure and the safety

valve fails to move, stop the boiler manually and takes corresponding measurements to reduce the

pressure.

10.25.3.4 When the boiler pressure is recovered, close the electromagnetic release

valve and contact the turbine group to close the high pressure bypass valve and low pressure

bypass valve.

10.25.3.5 Pay close attention to the work conditions of the automatic regulation control device of

the drum water level and the steam temperature and shift the mode to manual mode to regulate it

manually if necessary.

10.26 Auxiliary Failure

10.26.1 Faults and countermeasures of air preheater

10.26.1.1 Too low rotating speed

1) Faults

a) When the rotating speed of the air preheater during operation is as low as 0.2rpm, the

main motor trips and the red and yellow lamps flash.

b) Alarm for too low revolution is sounded.

c) The low speed motor is automatically started and if the over low speed lasts more than

80s, the low speed motor will automatically stop and the baffle plates of flue and air are

closed.

d) If the control power fails, the main motor trips and the low speed motor starts.

2) Countermeasures

a) Check whether the main motor and hydraulic coupling work normally;

b) Notice thermal operation personnel to check the rotating speed detector;

c) Check whether there is jamming or bump in the air preheater;

d) Control the continuous rotation on spot for a necessary period if possible for cooling;

e) Confirm the baffle plate of the inlet of the flue and the first thermal air baffle plate and the

second thermal air baffle plate are closed when the air preheater fails and is shut down.




10.26.1.2 High bearing temperature (≥60℃)

1) Faults

a) Alarm is sound for high temperature of bearing (TSH15, TSH25)

b) Lubricating oil pump starts automatically.

2) Countermeasures

a) When the bearing temperature is not less than 60℃ and the lubricating oil pump fails to

start, manually start it on DCS.

b) Check whether the oil pump runs normal and the oil level and the oil quality are regular.

c) If the temperature shows no decline after the starting of oil pump for a long time, check

whether the oil pressure difference of the filter is normal on site. If the pressure difference

is too large, shift to another filter and ask for maintenance of the filter at the trouble side.

d) Check whether the cooling water flows smoothly and whether there is leakage on the oil

pipeline.

e) The oil pump is automatically stopped when the oil temperature is declined to 50℃.

f) Check whether the air duct leaks, if any, notice relative personnel for maintenance.

10.26.1.3 Bearing oil pump trip

1) Faults

a) Yellow lamp and red lamp on the oil pump flash

b) Alarm is sound for high temperature of bearing

2) Causes

a) Oil pump motor fails or leak electrically

b) The mechanical part fails

3) Countermeasures

a) Notice relative personnel to eliminate the motor troubles timely

b) Recover 380V power supply




c) Eliminate the mechanical part troubles

d) Strictly monitor the air preheater bearing oil temperature and take necessary measures to

cool the oil.

10.26.1.4 Complete shutdown of the air preheater

1) Faults

a) MFT operation;

b) Interlocking trip happens to various auxiliary equipments and flameout happens in the

boiler;

c) Sector-shaped sealing baffle plate withdraws automatically;

d) The alarm that air preheater systems A and B fail is sounded from the alarm window.

2) Causes

a) The power of air preheater motor is lost;

b) The rotating speed of the air preheater is lower than 0.2rpm and the low speed motor fails

to start within 80s.

3) Countermeasures

a) Resolve it according to the method for MFT.

b) Confirm the air preheater is stopped;

c) Confirm the flue baffle plate of the air preheater inlet and the second thermal air baffle

plate of the outlet are closed;

d) Find out the reason and remove the trouble. Prepare the boiler for restart.

10.26.1.5 Trip of one air preheater

1) Faults

a) Lamp at the trip side of the air preheater flash and the alarm trump is sounded;

b) Induced draft fan, force fan and primary air fan at the corresponding side trip;

c) The alarm that air preheater fails at the trip side is sounded from the alarm window;




d) The load is recovered to 50% of MCR, and six pulverizer coal feeders including FEA,

FEE and FEI trip.

2) Causes

a) Mechanical jamming happens to the air preheater at the trip side;

b) The motor of the tripping air preheater fails or losses power;

c) Shutdown button or emergency button is pressed by mistake.

3) Countermeasures

a) The load is automatically inclined to 50% of MCR, the load of the set is turned to 50% of

MCR and the alarm is trigged.

b) Confirm the flue baffle plate of the air preheater inlet and the primary and the second

thermal air baffle plates of the outlet are closed, otherwise close them manually.

c) Air fan at the corresponding side automatically trips and the baffle plate at the outlet and

the inlet automatically close; otherwise close them manually.

d) Six pulverizer coal feeders including FEA, FEE and FEI trip automatically; otherwise trip

them manually.

e) Provide a proper amount of oil gun torches to facilitate and stabilize combustion.

f) Find out trip Causes and start relative equipment again after they are

inspected and proved to be normal.

g) Monitor the shutdown side.

h) Control the flue temperature and the air temperature at the inlet and the outlet of the air

preheater.

i) Send out a fire alarm.

10.26.2 Induced draft fan faults and countermeasures

10.26.2.1 Complete shutdown of two induced draft fans

1) Faults

a) MFT




b) The motors of the two induced draft fans are powered off and the outlet baffle plate is

automatically closed.

c) If the electric protections system starts to work, the alarm that induced draft system fails

is sounded from the alarm window.

d) The two force fans are interlocked and the two primary fans are stopped completely, the

total air amount and the air pressure are dropped to zero instantly.

e) The negative pressure in the furnace changes greatly and the fire in the boiler goes out.

2) Causes

a) When the furnace pressure is not less than 41mbar or not more than -25mbar, MFT fails

to start within 5s.

b) The number of the secondary air baffle plates of spark plug which is opened is less than

18.

c) All force fans trip.

d) All air preheaters trip.

e) The motor power is cut off.

3) Countermeasures

a) Dispose it according to the countermeasures to MFT.

b) When the baffle plates of the inlet and the outlet fail to open, open them timely or slowly

open the regulation baffle plate, keep the furnace draft pressure between 0Pa and 100Pa

and the ventilation in the furnace balanced to prevent furnace explosion.

c) If the induced draft fan fails to recover to start, keep the furnace in natural ventilation for

above 15min.

d) If the induced fan recovers to start, strictly conform to the furnace cleaning procedures

when the boiler recovers to start.

10.26.2.2 Trip of one induced draft fan

1) Faults

a) Alarm that induced draft fan fails at the trip side is sounded from the alarm window.




b) The inlet baffle plate and the outlet baffle plate of the induced draft fan at the trip side are

closed automatically.

c) The furnace draft pressure turns positive.

d) Force draft fan and primary air fan at the side corresponding to the interlinking trip.

2) Causes

a) The fan vibration is not less than 120μm

b) The shutdown button is pressed by mistake

c) Electric baffle plate of the outlet is automatically closed

d) The electric protection system starts to work

e) Mechanical faults

f) The air preheater at the corresponding side trips

g) The drive power supply at the corresponding side is cut off

h) The shift of air fan rotating speed fails

3) Countermeasures

a) If MFT takes place, shoot it according to the troubleshooting method for MFT.

b) The load should be automatically reduced to 50% of MCR, the alarm that the set load is

recovered to 50% of MCR is sounded from the alarm window.

c) Six pulverizer coal feeders of FEA, FEE and FEI trip automatically; otherwise shut down

the six pulverizer coal feeders of FEA, FEE and FEI manually.

d) Provide a proper amount of oil gun torch for facilitating combustion. After the combustion

is stable, determine whether to stop the pulverizer coal feeder according to its rotating

speed to avoid that the feeding is not proper due to the low rotating speed.

e) If the force fan and the primary air fan at the corresponding side fail to trip automatically,

stop them manually but keep the air preheater at the corresponding side running.

f) After the cause for tripping is found out, and the induced draft fan is inspected and proved

to be normal, the induced draft fan then can be restarted.




g) Monitoring at the shutdown side:

Monitor the flue temperature and the air temperature at the inlet and the

outlet of the preheater and fire alarm.

Check the induced draft fan bearing temperature and the temperature of the motor coil and

the bearing.

10.26.2.3 High temperature at bearing and coil

1) Alarm is sounded when the air fan bearing temperature TE01B, TE01D and the motor bearing

temperature TE01F, TE01H are high.

2) Find out the cause of high temperature at the bearing when the alarm is sounded and remove

it immediately.

3) If the bearing temperature is up to 95℃, the induced draft fan should be stopped.

4) Alarm is sounded when the motor coil temperature TE01I, TE01L and TE01M is high.

5) Find out the cause of high temperature at the coil when the alarm is sounded and remove it

immediately.

6) Check whether the motor is over loaded

7) Check whether the air cooler is normal and whether the filter screen at the inlet is blocked.

8) If the coil temperature is up to 120℃, the induced draft fan should be stopped

10.26.3 Force fan faults and countermeasures

10.26.3.1 Complete shutdown of two force fans

1) Faults

a) Tripping;

b) The baffle plates of the inlet and the outlet of the force fan are automatically closed;

c) The total air pressure and the total air amount are dropped to zero;

d) If the force fan trips due to accidents, the induced draft fans should be

automatically stopped completely as well as the primary air fans

e) Alarm that force fan systems A and B fail is sounded from the alarm window.




2) Causes

a) All induced draft fans trip;

b) All air preheaters trip;

c) The furnace pressure is more than 41mbar or less than -25mbar while the MFT does not

starts within 5s.

d) The motor power is cut off.

3) Countermeasures


b) If the force fan outlet baffle plate is closed, open it manually in time to keep ventilation in

the furnace and prevent furnace from explosion.

c) If the force fan fails to recover to start, keep the furnace in natural ventilation for above

15min. If the force fan recovers to start, strictly conform to the

furnace cleaning procedures when the boiler recover to start.

10.26.3.2 Trip of one force fan

1) Faults

a) The baffle plates of the tripped force fan inlet and outlet are closed automatically;

b) The cooling air balance disconnection damper is closed;

c) The load of the force fan in operation is increased. When it is running at a low speed, it

should be automatically shifted to high speed;

d) The negative pressure of the furnace is increased instantly, which may cause MFT;

e) The load is automatically reduced to 50% of MCR;

f) Pulverizer coal feeder of FEA, FEE and FEI automatically trip.

2) Causes

a) Air fan vibration is not less than 120μm;

b) The air preheater at the corresponding side trips;

c) The air preheater at the draft fan trips;




d) Electric protection system starts to work;

e) Mechanical faults;

f) Shutdown button or emergency button is pressed by mistake;

g) The outlet baffle plate of the air fan during operation is automatically closed;

h) The drive power supply is cut off.

3) Countermeasures


b) The load is automatically dropped to 50% of MCR, the load of the set is turned to 50% of

MCR and the alarm is trigged.

c) Six pulverizer coal feeders including FEA, FEE and FEI trip automatically; otherwise shut

them down manually.

d) Provide a proper amount of oil gun torches for facilitating combustion.

After the combustion is stable, determine whether to stop the pulverizer coal feeder

according to

its rotating speed to avoid that the feeding is not even due to the low rotating speed.

e) The baffle plates of the tripped air fan outlet and inlet are automatically closed as well as

cool air balance baffle plate; otherwise it should be closed manually.

f) After the cause for tripping is found out, and the force fan is inspected and proved to be

normal, it then can be restarted.

g) Monitor the shutdown side:

Monitor the flue temperature and the air temperature at the inlet and the

outlet of the preheater and fire alarm.

Check the temperature of the force fan motor and the bearing.

10.26.4 Faults and countermeasures of primary air fan

10.26.4.1 Outage of two sets of primary air fans

1) Faults

a) Alarm that “primary air pressure is very low” is given.

b) MFT takes place, pulverizer coal feeding is stopped and boiler is in fire-off.

c) Furnace draft maximizes instantly.




d) Auto shutdown of inlet baffle plate and outlet baffle plate of primary air fan as well as hot

primary air baffle plate.

e) Alarm of “fault of primary air system” is given.

2) Causes

a) Outage of all induced draft fans

b) Outage of all air preheaters

c) Power failure

3) Countermeasures

a) Solve by the countermeasure to MFT

10.26.4.2 Tripping of one primary air fan

1) Faults

a) Auto shutdown of inlet and outlet baffle plate of the tripping air fan and auto shutdown of

hot primary air baffle plate of the air pre-heater at the corresponding side

b) Instant increase of furnace draft which may result in MFT

c) Primary air pressure decreases, maybe to very low degree and MFT takes place if the

pressure does not recover in 10 seconds.

d) Auto decrease of loading to 50%of MCR

e) Alarm window gives alarm of “fault of primary air fan” at tripping side.

f) Auto tripping of six sets of FEA, FEE, FEI pulverizer coal feeders.

2) Causes

a) Tripping of air pre-heater at the corresponding side

b) Tripping of induced draft fan at the corresponding side

c) Fan vibration≥80μm

d) Electric protection

e) Mechanical failure

f) Auto shutdown of outlet baffle plate of fan during operation




g) Shutdown button or emergency button is pushed by mistake.

3) Countermeasures

a) Solve by the countermeasure to MFT.

b) If loading auto decreases to 50% of MCR, alarm window gives alarm that unit loading

recovers to 50% of MCR.

c) Inlet and outlet baffle plates of fan trip, hot primary air baffle plate auto

shuts down, otherwise, manually shut it down.

d) Six sets of FEA, FEE, FEI pulverizer coal feeders auto shut down, otherwise, manually

shut them down.

e) Put proper oil gun torch to support combustion, judge whether to shut down pulverized

coal feeder according to rotating speed of pulverized coal feeder after the combustion is

stabilized, and avoids uneven power feeding due to low rotating speed of pulverizer coal

feeder.

f) The machine can only be started up after ascertaining tripping reason and make sure

there is no other fault through checking up.

g) Monitoring of shutdown side

Smoke temperature and air temperature at the inlet and outlet of air pre-heater as well as fire

alarm

Temperature of primary air fan and motor bearing

10.26.5 Faults and countermeasures of coal pulverizing system

10.26.5.1 Emergency shutdown of coal pulverizing system

1) Coal pulverizing system should be shut down by “emergency shutdown (HSXH001)” in case

one of the following happens:

a) MFT takes place but coal pulverizing system dose not trip.

b) Coal pulverizing system is on fire and in explosion danger or explosion takes place.

c) Rotor emits violent vibration and impact sound.

d) People and equipment are endangered.




e) Cyclone separator is blocked and exhaust air is filled with lots of pulverized coal, which

results in quick rise of steam temperature and steam pressure of boiler.

f) Coal pulverizer does not trip when one condition for coal pulverizer tripping exists.

2) Coal pulverizer should be shut down in case one of the following happens:

a) Power of main motor abnormally increases or decreases.

b) Outlet temperature cannot be monitored due to display failure of outlet temperature of

coal pulverizer.

c) Cyclone separator is blocked.

d) Cyclone separator is seriously blocked.

e) There is abnormal metal impact sound in coal pulverizer.

f) During pulverized coal pouring, pulverized coal conveyer trips but guiding baffle

plate does not auto guide to pulverized coal bunker.

10.26.5.2 Spontaneous combustion or explosion of coal pulverizing system

1) Faults

a) Outlet negative pressure of coal pulverizer and inlet negative pressure of pulverized coal

exhauster change in large fluctuation.

b) Outlet temperature of coal pulverizer rises abnormally.

c) Spark is found at inspection hole and untight places of system.

d) During explosion, pulverized coal leakage and smoke leakage are found at untight places

of system, explosion valve protrudes or exposes and negative pressure at

furnace changes into positive pressure.

e) Metal wall temperature of pulverized coal bunker rises abnormally during spontaneous

combustion of pulverized coal in pulverized coal bunker.

2) Causes

a) Pulverized coal deposits for a long time in coal pulverizing system.

b) The temperature at broken coal outlet of coal pulverizer is over high.




c) Raw coal is of high volatile matter and outlet temperature of coal pulverizer in running is

not reduced correspondingly.

d) There is foreign fire or explosive in system.

e) Over high oxygen content in the system

3) Countermeasures

a) In case of spontaneous combustion at inlet of coal pulverizer, properly

increase coal feeding amount, reduce pulverized coal amount at loop of

classifier, reduce or cut off system draft and stop coal feeder; apply fire-

fighting equipment to put out a fire on occasion and all damper baffle plates

should be closed if gas fire-fighting equipment is applied.

b) In case horizontal tube at coal pulverizer inlet is on fire, coal pulverizing system should be

stopped running to extinguish fire.

c) In case of spontaneous combustion of pulverized coal bunker, coal pulverizing system or

pulverized coal conveyer should be stopped running immediately. Must

not convey pulverized coal towards the pulverized coal bunker and close moisture

absorption piping towards the pulverized coal bunker to reduce pulverized coal

completely; after pulverized coal level is reduced to certain height, increase pulverized

coal level immediately and press pulverized coal to extinguish fire; apply fire-fighting

equipment if pulverized coal press does not work (clean and dry pulverized coal bunker

after application).

d) After coal pulverizing system explodes, emergency shutdown of coal pulverizing system

should be carried out, close hand-operated valve and coupling cock valve for moisture

absorption piping of pulverized coal bunker, confirm tight closing of all

damper baffle plates, extinguish internal and external fire source and repair explosion

door.

e) Normal coal pulverizing can only be carried out after water in the system is drained away

as far as possible and the system is fully ventilated and dried if fire water is applied during

the fir fighting process.

10.26.5.3 Coal interruption in coal pulverizer

1) Faults

a) Coal interruption alarm is given and pulverized coal feeder trips after 30 seconds.

b) Noise level of coal pulverizer increases.






c) Outlet temperature of coal pulverizer rises; outlet temperature first reduces and then rises

if pulverized coal bunker is empty.

d) Negative pressure at pulverized coal bunker decreases.

e) Rotating speed of pulverized coal feeder maximizes during auto rotation.

2) Causes

a) There is no coal in raw coal bunker.

b) Raw coal bunker is blocked.

c) Driving part of pulverized coal feeder is in fault and driving belt skips or loosens.

d) Scraper chain for pulverized coal feeder breaks and falls down.

3) Countermeasures

a) Control outlet temperature of coal pulverizer at setting value and properly turns

down regulation baffle plate at inlet of exhaust air fan.

b) Note man on duty for combustion and conveying to feed coal or dredge coal bunker (start

up air gun).

c) Note maintenance personnel to eliminate equipment fault.

d) In case coal interruption lasts for 15 minutes and coal feeding cannot be recovered, coal

pulverizer should be shut down and pulverized coal exhauster and exhaust air fan should

be shut down on condition.

10.26.5.4 Coal jamming in coal pulverizer

1) Faults

a) Negative pressure at all points of system increase.

b) Power of coal pulverizer increases and power decreases in serious condition.

c) Noise of coal pulverizer decreases.

d) Pulverized coal runs out at inlet and outlet of coal pulverizer.

2) Causes

a) Coal feeding amount is over larger.




b) Noise measurement signal is incorrect and speed controller of coal feeding does not

work.

c) Measurement of rotating speed of coal feeding is incorrect.

d) Water content of raw coal is large, grindability decreases and hot smoke air temperature

at inlet is over low.

e) Ventilation decreases and coal feeding amount is not reduced during manual operation.

f) Bypass valve of coal pulverizer is opened by mistake, which results in

over low of ventilation in coal pulverizer and low temperature.

3) Countermeasures

a) Decrease coal feeding amount or shut down pulverized coal feeder on occasion.

b) Properly turn up baffle plate at inlet of exhaust air fan to increase system ventilation and

carry out pulverized coal pumping and attention should be paid to

maintaining outlet temperature of coal pulverizer at 110 DEG C.

c) Turn down coal pulverizer bypass at normal position.

d) In case outlet temperature of coal pulverizer increases, close hot smoke air manual baffle

plate HV001 on occasion and manually open cold air baffle plate TCV62B.

e) In case all above countermeasures do not work, shut down main motor of coal pulverizer

and restart up to carry out pulverized coal pumping after turning runs for 30 minutes.

f) In case pulverized coal pumping does not work, coal pulverizing system should be shut

down and manual drainage towards coal pulverizer should be carried out after relevant

departments approve and there are definite and effective countermeasures.

10.26.5.5 Blocking of classifier

1) Faults

a) Negative pressure at outlet of coal pulverizer decreases.

b) Negative pressure at inlet of pulverized coal exhauster increases.

c) Exhaust air volume decreases.

2) Causes




a) Air lock for pulverized coal returning pipe is blocked due to over large amount of returning

pulverized power.

b) Large humidity of returning pulverized coal results in blockage.

3) Countermeasure

a) Decrease coal feeding amount and attention should be paid to

maintaining outlet temperature of coal pulverizer at setting value.

b) Knock pulverized coal returning pipe and air lock to dredge pulverized coal

returning pipe.

c) If the above countermeasure does not work, coal pulverizing system should

be shut down and note maintenance personnel to repair.

10.26.5.6 Blockage of pulverized coal separator

1) Faults

a) Negative pressure at outlet of coal pulverizer decreases and negative pressure at inlet of

pulverized coal exhauster increases obviously.

b) When becoming series, pulverized coal exhausting amount and pulverized coal filled in

exhaust air increase, steam temperature and steam pressure rise at the same time and

oxygen content in fuel gas reduces.

c) Rotating speed of pulverized coal feeder reduces during self movement of total fuel.

d) Lock air under cyclone separator at blocking side does not work.

2) Causes

a) Pulverized coal is over damp, which results in blockage of pulverized coal pipe of cyclone

separator.

b) Lock air under separator does not work.

c) Coal pulverizing system is not shut down in time when pulverized coal bunker is full.

d) Pulverized coal conveyer trips and guiding baffle plate does not guide towards pulverized

coal bunker during pulverized coal preparation.

e) Guiding baffle plate guides towards pulverized coal conveyer by mistake.




f) During pulverized coal pouring, aerodynamic gate (UV06) from pulverized coal conveyer

to pulverized coal bunker is not opened.

3) Countermeasure

a) Knock position of air lock to dredge pulverized coal discharging pipe.

b) Coal pulverizing system should be shut down if pulverized coal bunker is full.

c) Have guiding baffle plate guide towards pulverized coal bunker if guiding baffle

plate moves by mistake.

d) In case pulverized coal conveyer trips during pulverized coal pouring and guiding baffle

plate does not guide towards pulverized coal bunker, have guiding baffle

plate guide towards pulverized coal bunker immediately and coal pulverizing system

should be shut down if guiding baffle plate cannot be rotated for being pressed by

pulverized coal.

e) After coal pulverizer is shut down during serious blockage, maintain

pulverized coal exhausting and operate exhaust air fan, however, baffle plate at inlet

of exhaust air fan cannot be over opened to guarantee normal operation of

pulverized coal feeder and dredge pulverized coal discharging pipe of cyclone

separator.

10.26.5.7 Tripping of exhaust air fan or coal pulverizer

1) Faults

a) Tripping signal is given, green light lights and red light and yellow light sparks.

b) Fan is out of operation.

c) Negative pressure at all points of system reduces to “zero”.

d) Exhaust air volume reduces to “zero”.

e) Hot smoke baffle plate is closed and coal pulverizer and pulverized coal feeder trip.

2) Causes

a) Power and motor are in failure.

b) There are tripping conditions.

c) Local shutdown button is pressed by mistake.

3) Countermeasure






a) Pulverized coal feeder and coal pulverizer are shut down and turning gear is put into

service.

b) Check out tripping reason and restart up after solving fault.

10.26.6 Faults and countermeasures of pulverized coal feeder

10.26.6.1 Pulverized coal feeder cannot be started up

1) Causes

a) Without starting up conditions

b) Primary air aerodynamic overall opening signal is not received.

c) Motor of pulverized coal feeder is not powered.

2) Countermeasures

a) Start up once starting up conditions are held.

b) Clear the fault that primary air aerodynamic overall valve cannot be opened in place.

c) Note power department to power motor of pulverized coal feeder.

10.26.6.2 Rotating of pulverized coal feeder cannot be speeded after starting up

1) Causes

a) Switch for local rotating speed control cabinet is not put in place of “ON”.

b) Rotating speed regulator is in fault or not powered.

2) Countermeasures

a) Put switch for local rotating speed control cabinet in place of “ON”.

b) Contact heat engineering personnel and clear fault.

c) Rotating speed regulator is powered.

10.26.6.3 Over large fluctuation of rotating speed of pulverized coal feeder in service

1) Faults

a) Over large fluctuation of rotating speed of pulverized coal feeder




b) Rotating speed increases or decreases abnormally when all pulverized coal feeders are

in auto operation.

2) Causes

a) Unsmooth blockage of scraper for pulverized coal feeder

b) Damage of mechanical part of pulverized coal feeder

c) Fault of rotating speed regulator

3) Countermeasures

a) Pulverized coal feeder is shut down at once to clear fault

10.26.6.4 Blockage of primary air pipe and pulverized coal discharging pipe

1) Faults

a) Primary air pressure of single pipe is abnormal and alarm is given in DCS, PSH or PSL.

b) Rotating speed of all pulverized coal feeders during auto operation is

increased abnormally and boiler temperature and steam pressure reduce during auto

operation.

c) Outer wall temperature of blocking primary air pipe and pulverized coal discharging pipe

is lower than that of normal pipes and is obviously lower than that of normal pipes during

serious blocking or equal to room temperature.

d) Pipe makes a clunk when being knocked.

2) Countermeasure

a) The pulverized coal feeder is shut down and primary air aerodynamic valve and hand

operated valve are closed.

b) Dredge the primary air pipe and pulverized coal discharging pipe.

10.26.6.5 Pulverized coal feeder does not discharge pulverized coal

1) Faults

a) Rotating speed of all pulverized coal feeders during auto operation

is increased abnormally and steam temperature and steam pressure of

boiler during manual operation reduce.




b) Temperature of the primary air pipe is lower than or close to room temperature.

c) Pipe makes a hollow sound when being knocked.

2) Countermeasures

a) Make sure all pulverized coal discharging gates should be all opened.

b) Knock upper wall of pulverized coal bunker to exhaust air of pulverized coal.

c) Contact maintenance personnel to check out whether mechanical parts of

pulverized coal feeder are in fault.

d) Carry out pulverized coal drop of pulverized coal bunker regularly subject to regulations.

10.26.7 Faults and countermeasures of fire detector cooling fan

10.26.7.1 Faults

1) Alarm that air pressure at air pressure outlet is low is given and MFT takes place when air

pressure is low to 70mbar.

2) 220V direct fan auto starts up.

10.26.7.2 Causes

1) Driving belt of fan loosens and skips.

2) Screen at fan inlet is blocked by impurities.

3) Hand operated valve at fan outlet is closed by mistake.

4) Electric protection takes place or power is off.

10.26.7.3 Countermeasure

1) When AC fan is in fault and trips or alarm of “low outlet air pressure” is given, DC fan should

auto start up, otherwise, manual starting up should be carried out at once.

2) In case DC fan cannot auto start up, air pressure is low to 70mbar and MFT does not take

place, emergency boiler shutdown button should be pressed to stop boiler operation.

3) Take effective measure to prevent flame scanner from being damaged.

10.26.8 Faults and countermeasures of oil gun cooling fan

10.26.8.1 Low air pressure




1) Faults

a) Alarm of low air pressure

b) When interlock is put into operation, standby fan is linked.

2) Causes

a) Air leakage of air system

b) Shedding of connecting hose

c) Tripping of fan in operation

d) Driving belt of fan loosens and skips.

3) Countermeasure

a) After standby fan is started up, find out the reason for low air pressure.

b) In case standby fan is not started up, it should be started up manually at once.

c) If the fault is caused by air leakage or mechanical reason, report to man on duty and note

maintenance personnel to clear the fault as soon as possible.

10.26.8.2 Tripping of fan

1) Faults

a) Yellow light of tripping fan sparks and red light sparks.

b) Alarm of low air pressure is given; when interlock is put into operation, standby fan is

started up.

2) Causes

a) Jam fault of machine and overcurrent of motor

b) Motor is off power or in fault.

3) Countermeasure

a) Operate standby fan and clear fault of fan.

b) When standby fan is not started up, standby should be started up at once.

c) Find out reason for motor and power fault and clear faults.




10.26.9 Faults and countermeasures of steam air heater

10.26.9.1 High water level of condensation water tank

1) Faults

a) Alarm of high water level of condensed water tank (LSH03) is given.

b) High water level of local condensed water tank water level gauge

2) Countermeasure

a) Make sure normal operation of water level control valve LCV05A on-site and open hand

operated valve thereof.

b) Make sure normal operation of water level control valve LCV05B on-site and open hand

operated valve thereof.

c) Contact heat personnel to inspect whether water level controller is in normal operation.

10.26.9.2 Low water level of condensation water tank

1) Faults

a) Alarm of low water level of condensed water tank is given.

b) Low water level of local water level gauge for condensed water tank

2) Countermeasure

a) Check out whether water drain valve is closed.

b) Check out whether water level control valve is in normal operation.

10.26.9.3 High steam pressure

1) Faults

Alarm of high steam pressure (PSH57) is given.

2) Countermeasure

a) Check out whether steam control valve TCV57A is in normal operation.

b) Check out whether bypass valve HV015 thereof is closed.

c) Make sure control valve for water level of condensed water tankand hand operated valve




thereof are opened, otherwise, manually open HV004 to release pressure.

d) In case steam control valve is in fault, inlet and outlet hand operated valves should be

closed and bypass hand operated valve should be opened to regulate manually.

10.26.9.4 Low steam pressure

1) Faults

Alarm of low steam pressure (PSL57) is given.

2) Countermeasure

a) Check out whether steam control valve PCV57A is in normal operation.

b) Average temperature of air smoke of air per-heater is over setting valve and

opening degree of steam control valve is small, steam air heater can be shut down.

c) Check out positions of all valves of system and make sure there is no leakage.

10.26.10 Faults and countermeasures of boiler water circulating pump

10.26.10.1 Two sets of boiler water pump trip, a standby pump is not started up or a boiler water

pump is in operation with differential pressure<1bar

1) Faults

a) MFT takes place.

b) Emergency indicating light for boiler water pump lights.

c) Alarm of “boiler water pump fault” is given.

2) Causes

a) Closed cooling water is interrupted or closed cooling water <27m3 /h (for 20 seconds).

b) Electric fault makes pump motor power off.

c) Temperature for boiler water pump≥65 DEG C.

d) After two pumps trip, standby pump does not have starting up conditions (temperature of

standby pump>55 DEG C).

e) Boiler water pump sub-control shutdown button is pressed by mistake.

3) Countermeasure




a) After MFT takes place, solve by the countermeasure to MFT.

b) Comprehensively inspect boiler water pump system at once to find out tripping causes

and take countermeasure.

c) Eliminate tripping reason and restart up boiler water pump after making sure there is no

other fault.

d) In case closed cooling water pump trips and reclosing is not carried out

successfully, emergency three-way valve should be opened at once;

enhance water feeding to emergency water tank, have closed cooling

water operate as soon as possible and prevent over high temperature of boiler

water pump which results in motor.

10.26.10.2 Two sets of boiler water pump trip, a standby pump is started up or a boiler water pump

trips but standby pump is not started up.

1) Faults

a) Loading auto reduces to 60% of MCR and alarm of “loading recovering” is given.

b) FEA, FEE, FEI pulverized coal feeders auto trip.

2) Causes

a) Standby pump does not standby condition (temperature of pump>55 DEG C).

b) Closed cooling water amount of motor of tripping pump<27m3 /h.

c) Temperature of tripping pump≥65 DEG C.

d) Independent shutdown button of pump in operation is pressed by mistake.

e) Power for tripping pump motor is off.

3) Countermeasure

a) Alarm that loading auto recovers to 60% of MCR and alarm window unit loading to 60%

of MCR is given.

b) FEA, FEI pulverized coal feeders auto trip, otherwise, they trip due

to manual interruption.

c) Put proper oil gun torch to support combustion, judge whether to shut down pulverized

coal feeder according to rotating speed of pulverized coal feeder after the combustion is




Absolute pressure

(Mpa)

Saturation temperature

(DEG C)

Absolute pressure

(Mpa)

Saturation temperature

(DEG C)

0.01 45.83 1.80 207.11 0.02 60.09 1.90 209.80 0.03 69.12 2.00 212.38 0.04 75.88 2.50 223.94 0.05 81.34 3.00 233.84 0.06 85.95 3.50 242.54 0.07 89.96 4.00 250.33 0.08 93.51 4.50 257.41 0.09 96.71 5.00 263.91 0.10 99.63 5.50 269.93 0.11 102.32 6.00 275.55 0.12 104.81 6.50 280.82 0.13 107.13 7.00 285.79 0.14 109.32 7.50 290.55 0.15 111.37 8.00 294.97 0.16 113.32 8.50 299.23 0.17 115.17 9.00 303.31 0.18 116.93 9.50 307.21 0.19 118.62 10.00 310.96 0.20 120.23 10.60 315.30 0.25 127.43 11.00 318.05

stabilized, and avoids uneven power feeding due to low rotating speed of pulverizer coal

feeder.

d) Comprehensively inspect tripping pipe, find out reason for tripping and

take some countermeasure.

e) After fault is cleared and make sure there is no other fault, a boiler water pump can only

be started up and gradually recover system.

10.26.10.3 A boiler water pump strips and standby pump is successfully started up

Find out tripping reason, eliminate the cause as soon as possible and put the

pump into interlocking and standby status.

11 Appendix

11.1 The contrastive list of the absolute pressure and temperature in saturated states

0.30 133.54 11.60 322.10




0.35 138.87 12.00 324.65 0.40 143.62 12.60 328.40 0.45 147.92 13.00 330.83 0.50 151.84 13.60 334.40 0.60 158.83 14.00 336.64 0.70 164.96 14.50 339.40 0.80 170.42 15.00 342.13 0.90 175.36 15.50 344.80 1.00 179.88 16.00 347.33 1.10 184.07 16.50 349.80 1.20 187.96 17.00 352.26 1.30 191.61 18.00 356.96 1.40 195.04 19.00 361.43 1.50 198.29 20.00 365.70 1.60 201.37 21.00 369.78 1.70 204.31 22.00 373.69

11.2 Boiler Cold start-up Curve


VIETNAM QUANG NINH THERMAL POWER JOINT STOCK COMPANY

Shanghai Electric (Group) Corporation 2×300 MW Anthracite Coal

Fired Power Station BOILER & AUXILIARIES OPERATION MANUAL

11.3 Boiler Hot star-tup Curve

11.3.1 Boiler Warm star-tup Curve





11.3.2 Boiler Hot star-tup Curve





11.3.3 Boiler Very Hot star-tup Curve





11.4 Boiler drume level vs load Curve


Shanghai Electric (Group) Corporation

VIETNAM QUANG NINH THERMAL POWER JOINT STOCK COMPANY 2×300 MW Anthracite Coal Fired Power Station

BOILER & AUXILIARIES OPERATION MANUAL

11.5 Boiler O2 in flue gas vs load Curve
