S O U R C E O F W A T E R : R I V E R H O O G H L Y

D A I L Y A V E R A G E I N T A K E : 4 0 , 0 0 0 K L

Plant Water Systems

Raw Water System

Clarified water System

DM Water System

DMCW system

CW System

ACW System

Service Water System

Plant Waters Systems

Fire Water System

Drinking Water System

DS System

Seal Water System

BA Zero Discharge System

Uses of Different Water

Raw water: Main source of water (from River Ganges).

Clarified water: Forebay make up, Service & Fire water.

DM water: Power cycle make up, DMCW make up.

DMCW: Cooling medium in different Boiler & TG aux. and Compressors.

Circulating Water: Condensation of steam in condenser

Aux. Cooling Water: DMCW cooling & TG Lub oil cooling.

Service Water: Washing , cleaning & different cooling purpose.

Uses of Different Water

Fire Water: Hydrant water & Mulsifire water

Drinking Water: Drinking

DS System: for dust suppression & fire management at coal stock pile

Seal Water System: for gland sealing of HP/LP Pp. & HCSS Charge Pp

BA Zero Discharge System: for bottom ashing

Specification of Intake Pumps

Make: Kirloskar Brothers Ltd

Type: Centrifugal

Capacity: 1750 m3 / Hr

Head (shut off): 41 m

Head ( dynamic): 28 m

Speed : 980 rpm

Efficiency: 86.05%

Power input: 155.07 kW

Impurities at RAW Water

1. Suspended Particles

a. Can be settled out (Silica)

b. Collidal Impurities (slightly –ve charged

particles )

2. Dissolved Impurities ( minerals )

3. Dissolved Gasses (CO2, O2)

4. Organic Impurities (Algae, Bacteria, Fungi)

Impurities at Ganges water

Bicarbonate salts

Silica

Chlorides & Sulphate (Trace)

Oil & Biocides

Effects of Impurities

Sodium/Iron/Copper : Boiler/Turbine Deposits.

Bicarbonate Hardness : Boiler/Turbine Deposits

Organics/Oil : Foaming in Boiler Drum

Silica : Boiler/Turbine Deposits

Dissolved O2 & CO2 : Corrosion by localised cell formation

FM

Flocculation Tank

ISS

Raw water from River Ganges

CWR

FWR DMP

Raw water System

Daily Consumption:46000Ton

Raw water treatment

Processes:

1. Coagulation process

2. Chlorination process

3. Ion exchange process

Raw water treatment

Raw water to Clarified water:-

1. Alum dosing: to remove colloidal impurities

2. Polyelectrolyte dosing: to remove colloidal impurities

3. Sodium hypo-chloride: to remove organic impurities

4. NaOH dosing at FM: to reduce Ca loading.

Clarified Water Parameters

CWR water quality: • Total Hardness: 80 – 150 ppm

• Total Anion: 170 ppm as CaCO3

• Silica: 8 – 12 ppm as SiO2

• Chloride: 15 – 25 PPM as CaCO3

• Sulphate: 5 – 10 ppm as CaCO3

• Turbidity: 5 NTU

• pH: 7.0 to 7.5

ACF

FWR

SAC DG

Blower WBA SBA

MB DMST

GSF

De-mineralisation System

De-mineralisation

Clarified water to DM water:-

1. GSF: removes suspended particles

2. ACF: for Organic impurities, excess Cl2 & colour, odor.

3. SAC (Strong Acid Cation): to remove salts of Ca, mg, Na etc.

Ca(HCO)3 + R-H : R-Ca + H2CO3

4. Degasser: removes dissolved Co2 & H2Co3

De-mineralisation

5. WBA(Weak Base Anion): Strong anions are removed

H2SO4 + R-OH = R2SO4 + H2O

HCl + R-OH = RCl + H2O

6. SBA(Strong Base Anion): Weak anions like Si

H2SiO3 + R-OH : R2SiO3 + H2O

7. MB(Mixed Bed): Residual / spillage cations & anions are removed

Limiting DM Water parameters

Ph : 6 – 7.2

Conductivity : < 1.2 µs/cm

Silica : < 0.02 ppm

DM storage capacity

DMST ( 2 nos) : 1000 Ton

CST (2 nos) : 800 Ton

DMCW circuits

The two DMCW circuits are interconnected through Main plant Compressor supply & return lines.

Number of DMCW pumps : 4 nos for unit-1 & 3 nos for unit-2

Point of usage : All Coolers & Heat exchangers except where ACW is used

Specification of DMCW Pumps

Make: M/s Beacon Weir

Type: Centrifugal

Capacity: 870 cum/hr

Total head: 48 m

Efficiency: 84%

NPSHR: 5.7 m

Speed: 1480 rpm

Power Input: 130.71 kw

DMCW parameters & Treatment

Caustic (NaOH) dosing is done at DMCW tank to maintain the alkalinity (to avoid acid corrosion)

Parameters:

Ph: 8.5 to 8.8

Conductivity: 3 µs/cm

CW system

Number of pumps : Two for each unit (discharge side interconnection provided)

Water source: Forebay

Discharge valve is hydraulically operated

Supplies water only to Condenser

The water gets cooled in Cooling Tower

Specification of CW Pumps

Make: WPIL

Capacity: 15500 m3/hr

Speed: 497 rpm

No of stages: single

Total dynamic head: 26 mwc

Pump efficiency: 89%

Pump input at dynamic pr.: 1233.14 kw

ACW system

Number of pumps : Two for each unit (discharge side interconnection provided)

Water source : Forebay

Discharge valve is electrically actuated

Return line is connected with CW return line

Supplies water only to TG Lub oil Cooler, Nash pump cooler, Central AC plant Condenser (new provision) & DMCW HEX.

Provision of CT blowdown from CW-ACW return line.

The CT blowdown water is consumed through Service water & Zero discharge make-up.

Specification of ACW Pumps

Make: Kirloskar Brothers Ltd

Type: Centrifugal

Capacity: 2400 m3/hr

Head: 34.358 MWC

Speed: 1485 rpm

Input power: 250.9 kW

Forebay water treatment

H2SO4 dosing: to reduce by-carbonate salt.

Chembond dosing: to increase the solubility of salt to avoid scale formation.

NaOCl dosing: to destroy the organic matters.

Forebay water parameters

Ph : 8.5 – 8.9

Turbidity : < 20 NTU

Free Chlorine : < 0.5 ppm

Service water system

Number of pumps : 4

Suction side can be connected to CT blowdown as well as CWR

Usage : Washing/cleaning, Air Heater & ESP hopper cooling, ESP fogging, Sludge water pump gland cooling, Ammonia gas cylinder cooling, Dust Suppression tank make-up, Intake pump gland & Bearing cooling

Provision for interconnection with Hydrant line

Hydrant &

Mulsifyre

Pumps

Hydrant Pumps supply water at 9 Kg/Cm2 pressure through the network.

Hydrant Pumps -02 (Elec), 01(Diesel)

Mulsifire Pump- 01 (Elec), 03(Diesel)

Jockey

Pumps

There are two Jockey pumps which maintain the water pressure in both

Hydrant & Mulsifyre System

Hydro

pneumatic

Tank

This tank can store sufficient volume of water at 9 Kg/cm2 pressure and

is connected to both hydrant & mulsifyre systems . Two motor driven

compressors maintain the pressure inside the tank

Source of

Water for

Fire

Fighting

An underground Reservoir is connected to CW Forebay (capacity 7000

M3). This capacity enables the three Hydrant Pumps to spray water for

TWO HOURS and two High Velocity Water pumps for FOUR HOURS

simultaneously

Fire Water System

Cooling Towers

No. of Cooling Towers: 4

No. of Cell: 2*10 in Unit-1 & 2, 6 in Unit-3

No. of fans: 20 in Unit 1 & 2. 6 in Unit-3

Model: Induced draft counter flow cell cooling tower

Type of Fan: Axial flow

Rated speed: 740rpm / 1480 rpm

Power Input: 14 / 55kw Hot water temperature: 43oC

Cold water temperature: 33oC

CT efficiency : 78%

Compressed Air Systems

(1) Instrument air (2) Service air are of Reciprocating Type Number of IA Comp : 11 (No After cooler, discharge goes to ADP) Modes : Base-1, Base-2, S/B-1 & S/B-2 Provision of bleeding in local IA receivers for ID/FD/PA fan suction

vanes for prevention of moisture ingression into I to P converters Number of SA Comp : 3 (with After cooler) Modes : Base, S/B-1 & S/B -2 Provision of interconnection of SA with F&A IA system Provision of bleeding holes in oil gun atomizing bus for prevention

of moisture ingression in oil guns Number of ADPs : 3 Comp motor rating : 140 KW, 415 volts (3)Conveying Compressor are of Centrifugal type.

Basic Layout of IA system at FHP & AHP

IA-2

IA-3

IA-4

IA-5

IA-1 H O T

A I R

B U S

ADP-1

ADP-2

ADP-3

ADP-4

AIR

RECEIVER

Different uses of compressed air

IA is used for controlling purpose (Dumper or valve operation, FG operation etc), BOBR unloading, Ash evacuation system, Dry Fog System & Generator purging.

Conveying Air required for Fly Ash Evacuation

Screw Compressor Discharge Air used in multipurpose by change over of valves.

Service Air Compressor used for Atomization of oil and for other cleaning & Brg. Cooling purpose.

Specification of different compressors

Reciprocating Compressors:

Make: Chicago Pneumatic (I) Ltd

Type : Horizontal, stationary, reciprocating

Quantity : 19 (IA: 12,SA: 4, Conv. Comp: 3)

Capacity 25 m3/min

Discharge pressure : 8 kg/cm2 g

Compressor efficiency: 83%

Volumetric efficiency: 75.8%

Input power: 140.3 kw

Speed: 635 rpm

No of stages : 2

Specification of different compressors

Centrifugal Compressors:

Make: Kirloskar Pneumatic Co. Ltd

Type : Centrifugal

Quantity : 4

Capacity 60 m3/min

Discharge pressure : 3.7 kg/cm2 g

Input power: 675 Kw

Cooling: Water Cooled Intercooler, After

Cooler and oil cooler

Lubrication: Forced Feed Lubrication

Specification of different compressors

Screw Compressor:

Make: Ingersoll Rand

Type: Screw

Quantity: 1

Capacity: 20 m3/min

Discharge Pressure: 7 kg/cm2

Input Power: 128 Kw

Thank You