302 Project PDF

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Given Values:

600 MW coal fired plant

18 % excess air

Proximate Analysis:

Moisture

12

VM 38.4

FC 43.6

Ash 6

Total 100

11030

Heating Value(BTU/lb asreceived)

Ultimate Analysis (wt. %):

Carbon

62.6

Hydrogen 4.5

Nit

rogen 1.2

Sulfur

0.7

Ash 6

Oxygen 13

Total

88



Total 88

1 atm all throughthe gas streamtable 8 for enthalpies for heatloss through stack(do each materialseparately)stack to ambientfor stack gas

38% means itburns C + 1/2 O2 =COrest does C + H2O= CO + H2O



Ultimate Analysis(wt. %): AIR

Carbon 62.6% 18% excess

Hydrogen 4.5% 60% humidity

Nitrogen 1.2%

Sulfur 0.7%

Oxygen 13% ambient pressure 760 mmHg

Water 12%

vapor pressure of H2O at 26.7Celsius 26.271 mmHg

Ash 6% Total W/o H2O 88%mol fraction of wat er in ai r 0. 02 07 40 26 31 57 89

Assume: coal feed rate

100 lb/h

mass flow rate(lb/h) lb mole flow rate lb mole flow rate

lb mole O2required

Carbon 62.6 5.22 5.21 5.22

Hydrogen (H2) 4.5 2.23 2.23 1.11

Nitrogen (N2) 1.2 0.04 N2 sent to each

NO 0.02 0.02

N2 0.03 0.00

Sulfur (S) 0.7 0.02 0.02 0.02

Oxygen (O2) 13 0.41 0.41 -0.41

Water 12 0.67 0.67

Ash 6

total required O2= 5.963 l b mole

Dry air required= 28.39 l b mole/h

Wet air required = 28.99 Actual air sent= 34.20 lb mole/h

979.10 lb/h Productsmass flow rate (lbmole/h)

mass flow rate(lb/h)

0.49 tons/hour CO2 5.22 229.53mass air sent/mass fuel 9.79 lb air/lb coal H2O 2.23 40.14

Moisture in air= 0.71 lb mole/h

12.78 lb/h NO 0.01 0.26

O2 7.03 lb mole/h

N2 26.46 lb mole/h SO2 0.02 1.40

O2 1.07 0.03

0.0156 lb moisture/lb air Moisture in coal 0.67 12.00

Moisture in air 0.71 0.04

Ash 6.00

N2 26.49 741.62



Given

600 MW n:

33% thermal efficency (%) 0.709400817299805 moisture mols 28.6151755 total lbs/ lb-mole = M

3412000 (Btu/h)/MW 7.0338744980693 O2 mols n = m/M

11030 Btu/lb coal 26.4607659689274 N2 mols PV = nRT = m/M * RT

3.63E-05 ton/ft3 m/V = PM/RT

0.7302413gas constant R (ft^3 *atm *R^−1* lb-mol^−1) 0.072610887742931 lb/ft^3

0.000036305443871 tons/ft^3

coal feed rate= 562,433.03 lb coal/h

281.22 ton coal/h

air feed rate withrespect to the fuelfeed rate 9.79 lb air/lb coal

Molecular weight of WET air

required air feedrate 2,753.40 ton air/h ton air/ton coal 9.79103780200597 28.63

mole air/mole coal 4.10448495411558

Air flow ratethrough the FD fan 75,839,908.68 SCFH

ACFM = SCFM *(Tact / Tstd) 83,188,055.93 ACFH

Standard assumes492 R and 1 atm.



Given data

99.9% Ash removed 90% S2 captured

0.1% Ash leaving ESP 10% S2 released

5% bottom ash

total input gaseslong story short(output)

mass flow rate(lb/h) ton/h lb/h

CO2 229.53 229.53

H2O 52.18 52.18

NO 0.26 0.26

SO2 1.40 0.1400

O2 0.03 0.03 Ash 5.70 0.00000285 0.01

N2 741.62 741.62



Given

80% NO removed

20% NO leaving

Inputmass flow rate(lb/h)

mass of NOreacting

molar flow rate of NO (lb mole/h)

NH3 Required (lbmole/h)

NH3 required(ton/h)

NO 0.26 0.206 0.007 0.005 0.00007

Products lb mole/h

N2 0.006

H2O 0.007

NO 0.002



Stack Gasses lb/h lb mole/h mole fraction (wet) mole fraction (dry) mole % (wet) mole% (dry)

CO2 229.533 5.217 0.151 0.165 15.075 16.452

H2O 52.190 2.896 0.084 8.369 0.000

NO 0.051 0.002 4.95E-05 5.41E-05 4.95E-03 5.41E-03

SO2 0.140 0.002 6.32E-05 6.90E-05 6.32E-03 6.90E-03

O2 0.033 0.001 3.02E-05 3.30E-05 3.02E-03 3.30E-03

N2 741.627 26.487 0.765 0.835 76.541 83.532

Ash 0.006

Wet total 34.605

Dry Total 31.708

Molecular weightMolecular weight(dry) lb wet flue gas/h

29.582 30.638 lb/lb mole 1,023.676 0.003 lb mole/SCF ideal

lb flue gas/lb fuel flue gas

From Book: 10.237 367,499.610 SCFH

T (C) 44.500 44.600P (mmHg) 70.050 70.410

Partial Pressure of Steam in Stack (inmmHg): 63.608

Partial Pressure =Vapor Pressure atDew Point

Dew Point LeavingStack in degreesCelsius (using thesteam tables in thebook): 42.711

Conversion toDegrees F: 108.879

Maintenancetemperature (F) 188.879



gas mol % h (188.887 F) h (80 F) delta h (contributed)

CO2 15.075 1029.00102 26.8695652173913 151.072369066587

H2O 8.369 905.79247 24.1304347826087 73.7904489376691

NO 0.005 797.258306 21.3036036036036 0.038440305810614

SO2 0.006 0.000148691025506

O2 0.003 1521.13579 21.1304347826087 0.045318827447725

N2 76.541 779.47269 20.8695652173913 580.643383600527

total flue 805.59 btu/lb-mol

heat loss 27,877.05 btu/hr

SO2

a 3.89E-02

b 3.90E-05

c -3.10E-08

d 8.61E-12

t1 8.72E+01

t2 2.67E+01



HP Turbine IP Turbine

temp 1,000.000 F temp 1,000.000 F

pressure 2,520.000 psig pressure 587.000 psig

2,520.068 psia 587.068 psia

enthalpy 1,457.370 btu/lb 1,517.590 btu/lb

4,080,000.000 lb/hour 3,770,000.000 pounds/h

Coal11,030.000 BTU/lb

562,433.034 pounds coal/ h

Air 6,203,636,363.64 enthalpy coal 5,946,069,600.000

high pressureturbine enthalpy

543,495,919.555 pounds air/hour 400,095,498.28 enthalpy air 90.041 %

Dry air: 6,603,731,861.92total boiler enthalpy/h 5,721,314,300.000

low pressureturbine enthalpy

0.000 h (77 F) (btu/lb-mol) 86.638 %

160 h (100 F) (btu/lb-mol)

20.870 h (80 F) (btu/lb-mol) 20.8695652173913

20.437 h (80 F) (btu/lb-mol)in wet air

0.708h (80 F) (btu/lb) inwet air

H2O

0 h (77 F) (btu/lb-mol)

185 h (100 F) (btu/lb-mol)

24.130 h (80 F) (btu/lb-mol)

0.500h (80 F) (btu/lb-mol)in wet air

0.028h (80 F) (btu/lb) inwet air

Wet air:0.736151797813036 btu/hr

Feed Air: mol % mass mass %

Mositure 0.709 2.074 37.332 1.305

O2 7.034 20.564 658.063 22.997

N2 26.461 77.362 2,166.123 75.698

34.204 100.000 2,861.518 100.000



0.958

6,203,636,363.636

3412000 (Btu/h)/MW



Input lbmole/h Btu/h kJ/h T unit a b/2 c/3 d/4 [1]

coal 6,203,636,363.64 6,545,182.85 H2O C 3.35E-02 3.44E-06 2.53E-09 -8.98E-13

Air 80F N2 C 2.90E-02 1.10E-06 1.91E-09 -7.18E-13

H20 0.71 O2 C 2.91E+01 5.79E-06 -2.02E-09 3.28E-13

N2 26.46 CO2 C 3.61E-02 2.12E-05 -9.62E-09 1.87E-12

O2 7.03 NO C 2.95E-02 4.09E-06 -9.76E-10 9.10E-14

80F= 26.67 C= 299.67 K SO2 C 3.89E-02 1.95E-05 -1.03E-08 2.15E-12

Outputmass flow rate (lbmole/h)

CO2 5.22

H2O 2.23 Hrxn=

SUM mole floe rate of species i times Int(a+bT+cT^2+dT^3)dT

NO 0.03

SO2 0.02

O2 1.07

Moisture in coal 1.00 Total water 3.94 lb mole/h

Moisture in air 0.71 31874.4552406586

Ash Tad 1766.37 C 2039.37 K

N2 26.49 Tref 25 C

del H- delHcL -2.40E-07



Answers• Coal and air feedrates in tons/h

Coal feed rate (tons/h) 281.217 ton coal/h

Air feed rate (tons/h) 2,753.402 ton air/h

Air flow rate in ACFH through the FD fan (units)

• Calculate the air flow rate in ACFHthrough the FD fan,

Flue gas composition (wet basis) 83,188,055.93 ACFH

CO2

• Flue gascomposition on wetand dry basis,

H2O mole fraction (wet) mole fraction (dry)

N2 CO2 0.15075 0.16452

O2 H2O 0.08369

SO2 NO 4.95E-05 5.41E-05

NO2 SO2 6.32E-05 6.90E-05

Total O2 3.02E-05 3.30E-05

Flue gas molecular weight (wet) N2 0.76541 0.83532

Flue gas composition (dry basis)

CO2

• Flue gas flowrate in SCFH throughthe ID fan,

N2 367,499.61 SCFH Assuming idealconditions

O2

• Flue gasproduced per lb of fuel, Flue gasmolecular weight, Fluegas molecular weight(dry)

SO2 10.2367579281556 lb flue gas/lb fuelNO2 29.5821470888896 Molecular weight

Total 30.6382258504926Molecular weight(dry)

Flue gas molecular weight (dry)

• Ash flow ratefrom the ESP intons/h.

Flue gas produced per lb fuel 0.00000285 ton/h

Ash flow rate from ESP (tons/h)• Ammoniarequirement in tons/h

Ammonia requirement (tons/h) 0.000068571428571NH3 required(ton/h)

% of the heat input captured by the high pressure turbine

• What percent of the heat input iscaptured by the highpressure turbine andintermediate pressureturbine steam?

% of the heat input captured by the intermediate pressure turbine steam

Heat loss through stack• Heat lossthrough the stack.

Adiabatic temperature that can be achieved• The adiabatictemperature that canbe achieved by thiscoal in the combustionchamber. 2039.37 K

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302 Project PDF