302 project xls
DESCRIPTION
Rob SwahlTRANSCRIPT
Given dataGiven Values:
: This is the basic command tab. Change a number on here and it
changes the corresponding values on the other tabs-Scott
Dombrosky
600MW coal fired plant18% excess air
Proximate Analysis:Moisture12VM38.4FC43.6Ash6Total100
11030Heating Value (BTU/lb as received)
Ultimate Analysis (wt. %):Carbon62.6Hydrogen4.5Nitrogen1.2Sulfur0.7Ash6Oxygen13Total88
Overall Efficiency (%)33
Required Sulfur Dioxide (SO2) Emissions Captured (%)99
Particulate Collection (ESP) efficiency (%)99.9
Ambient Temperature fuel enters at (F)80
Relative Humidity (%)60
Forced air draft fan and induced air draft fan balance furnace draft
Unburnt fuel loss (%)0.2
Selective catalytic reduction system reduces NOx by ___ % using NH380
% of fuel nitrogen forms NO that reacts with NH3 to reduce N2 over catalyst40
Particulate collection = bag house = esp
% of total ash that flows as bottom ash from the combustion chamber (rest captured by ESP)5
clean gas goes through stack at:80degrees F above dew point of gas
steam to high pressure turbine:1000F2520psig
flow rate of high pressure steam (lb/h)4080000
lbs after expansion to 653 psig to go back to the heater3770000
heater heats it to:1000F587psig
Schematic
1 atm all through the gas streamtable 8 for enthalpies for heat loss through stack (do each material separately)stack to ambient for stack gas38% means it burns C + 1/2 O2 = COrest does C + H2O = CO + H2O
BoilerUltimate Analysis (wt. %):AIRCarbon0.6260.18excessHydrogen0.0450.6humidityNitrogen0.012Sulfur0.007Oxygen0.13ambient pressure760mmHgWater0.12vapor pressure of H2O at 26.7 Celsius26.271mmHgAsh0.06Total W/o H2O0.88mol fraction of water in air0.0207402632
Assume:coal feed rate100lb/h
mass flow rate (lb/h)lb mole flow ratelb mole flow ratelb mole O2 requiredCarbon62.65.225.215.22Hydrogen (H2)4.52.232.231.11Nitrogen (N2)1.20.04N2 sent to eachNO0.020.02N20.030.00Sulfur (S)0.70.020.020.02Oxygen (O2)130.410.41-0.41Water120.670.67Ash6total required O2=5.963lb moleDry air required=28.39lb mole/hWet air required =28.99Actual air sent=34.20lb mole/h979.10lb/hProductsmass flow rate (lb mole/h)mass flow rate (lb/h)0.49tons/hourCO25.22229.53mass air sent/mass fuel9.79lb air/lb coalH2O2.2340.14Moisture in air=0.71lb mole/h12.78lb/hNO0.010.26O27.03lb mole/hN226.46lb mole/hSO20.021.40O2 1.070.030.0156lb moisture/lb airMoisture in coal0.6712.00Moisture in air0.710.04Ash6.00N226.49741.62
Required Coal and Air Flow RateGiven600MWn:0.33thermal efficency (%)0.7094008173moisture mols28.6151755474total lbs/ lb-mole = M3412000(Btu/h)/MW7.0338744981O2 molsn = m/M11030Btu/lb coal26.4607659689N2 molsPV = nRT = m/M * RT3.63E-05ton/ft3m/V = PM/RT0.7302413gas constant R (ft^3* atm*R^1*lb-mol^1)0.0726108877lb/ft^30.0000363054tons/ft^3
coal feed rate=562,433.03lb coal/h281.22ton coal/h
air feed rate with respect to the fuel feed rate9.79lb air/lb coalMolecular weight of WET airrequired air feed rate2,753.40ton air/hton air/ton coal9.79103780228.63mole air/mole coal4.1044849541Air flow rate through the FD fan75,839,908.68SCFHACFM = SCFM * (Tact / Tstd)83,188,055.93ACFHStandard assumes 492 R and 1 atm.
ESPGiven data0.999Ash removed0.9S2 captured0.001Ash leaving ESP0.1S2 released
0.05bottom ash
total input gaseslong story short (output)mass flow rate (lb/h)ton/hlb/hCO2229.53229.53H2O52.1852.18NO0.260.26SO21.400.1400O20.030.03Ash5.700.000002850.01N2741.62741.62
NOx Catalytic ReductionGiven0.8NO removed0.2NO leaving
Inputmass flow rate (lb/h)mass of NO reactingmolar flow rate of NO (lb mole/h)NH3 Required (lb mole/h)NH3 required (ton/h)NO0.260.2060.0070.0050.00007
Productslb mole/hN20.006H2O0.007NO0.002
Stacks
Stack Gasseslb/hlb mole/hmole fraction (wet)mole fraction (dry)mole % (wet)mole% (dry)CO2229.5335.2170.1510.16515.07516.452H2O52.1902.8960.0848.3690.000NO0.0510.0024.95E-055.41E-054.95E-035.41E-03SO20.1400.0026.32E-056.90E-056.32E-036.90E-03O20.0330.0013.02E-053.30E-053.02E-033.30E-03N2741.62726.4870.7650.83576.54183.532Ash0.006
Wet total34.605Dry Total31.708
Molecular weightMolecular weight (dry)lb wet flue gas/h29.58230.638lb/lb mole1,023.6760.003lb mole/SCFideal
lb flue gas/lb fuelflue gasFrom Book:10.237367,499.610SCFHT (C)44.50044.600P (mmHg)70.05070.410
Partial Pressure of Steam in Stack (in mmHg):63.608Partial Pressure = Vapor Pressure at Dew PointDew Point Leaving Stack in degrees Celsius (using the steam tables in the book): 42.711
Conversion to Degrees F:108.879
Maintenance temperature (F)188.879
Stack heat lossgasmol %h (188.887 F)h (80 F)delta h (contributed)CO215.0751029.0010226.8695652174151.0723690666H2O8.369905.7924724.130434782673.7904489377NO0.005797.25830621.30360360360.0384403058SO20.0060.000148691O20.0031521.1357921.13043478260.0453188274N276.541779.4726920.8695652174580.6433836005total flue805.59btu/lb-molheat loss27,877.05btu/hrSO2a3.89E-02b3.90E-05c-3.10E-08d8.61E-12t18.72E+01t22.67E+01
Turbine Heat CaptureHPTurbineIP Turbinetemp1,000.000Ftemp1,000.000Fpressure2,520.000psigpressure587.000psig2,520.068psia587.068psiaenthalpy1,457.370btu/lb1,517.590btu/lb4,080,000.000lb/hour3,770,000.000pounds/h
Coal11,030.000BTU/lb562,433.034pounds coal/ hAir6,203,636,363.64enthalpy coal5,946,069,600.000high pressure turbine enthalpy543,495,919.555pounds air/hour400,095,498.28enthalpy air90.041%Dry air:6,603,731,861.92total boiler enthalpy/h5,721,314,300.000low pressure turbine enthalpy0.000h (77 F) (btu/lb-mol)86.638%160h (100 F) (btu/lb-mol)20.870h (80 F) (btu/lb-mol)20.869565217420.437h (80 F) (btu/lb-mol) in wet air0.708h (80 F) (btu/lb) in wet airH2O0h (77 F) (btu/lb-mol)185h (100 F) (btu/lb-mol)24.130h (80 F) (btu/lb-mol)0.500h (80 F) (btu/lb-mol) in wet air0.028h (80 F) (btu/lb) in wet airWet air:0.7361517978btu/hr
Feed Air:mol %massmass %Mositure0.7092.07437.3321.305O27.03420.564658.06322.997N226.46177.3622,166.12375.69834.204100.0002,861.518100.000
0.9586,203,636,363.636
3412000(Btu/h)/MW
Adiabatic Flame TemperatureInputlbmole/hBtu/hkJ/hT
unitab/2c/3d/4
: These numbers are wrong
coal6,203,636,363.646,545,182.85H2OC3.35E-023.44E-062.53E-09-8.98E-13Air 80FN2C2.90E-021.10E-061.91E-09-7.18E-13H200.71O2C2.91E+015.79E-06-2.02E-093.28E-13N226.46CO2C3.61E-022.12E-05-9.62E-091.87E-12O27.03NOC2.95E-024.09E-06-9.76E-109.10E-1480F=26.67C=299.67KSO2C3.89E-021.95E-05-1.03E-082.15E-12Outputmass flow rate (lb mole/h)CO25.22H2O2.23Hrxn=SUM mole floe rate of species i times Int(a+bT+cT^2+dT^3)dT
NO0.03
SO20.02O21.07Moisture in coal1.00Total water3.94lb mole/hMoisture in air0.7131874.4552406586AshTad1766.37C2039.37KN226.49Tref25C
del H- delHcL-2.40E-07
Answers_ Bulleted pointsAnswersCoal and air feed rates in tons/hCoal feed rate (tons/h)281.217ton coal/hAir feed rate (tons/h)2,753.402ton air/hAir flow rate in ACFH through the FD fan (units) Calculate the air flow rate in ACFH through the FD fan,Flue gas composition (wet basis)83,188,055.93ACFHCO2 Flue gas composition on wet and dry basis,H2Omole fraction (wet)mole fraction (dry)N2CO20.150750.16452O2H2O0.08369SO2NO4.95E-055.41E-05NO2SO26.32E-056.90E-05TotalO23.02E-053.30E-05Flue gas molecular weight (wet)N20.765410.83532Flue gas composition (dry basis)CO2 Flue gas flow rate in SCFH through the ID fan,N2367,499.61SCFHAssuming ideal conditionsO2 Flue gas produced per lb of fuel, Flue gas molecular weight, Flue gas molecular weight (dry)SO210.2367579282lb flue gas/lb fuelNO229.5821470889Molecular weightTotal30.6382258505Molecular weight (dry)Flue gas molecular weight (dry) Ash flow rate from the ESP in tons/h.Flue gas produced per lb fuel0.00000285ton/hAsh flow rate from ESP (tons/h) Ammonia requirement in tons/hAmmonia requirement (tons/h)0.0000685714NH3 required (ton/h)% of the heat input captured by the high pressure turbine What percent of the heat input is captured by the high pressure turbine and intermediate pressure turbine steam?% of the heat input captured by the intermediate pressure turbine steamHeat loss through stack Heat loss through the stack.Adiabatic temperature that can be achieved The adiabatic temperature that can be achieved by this coal in the combustion chamber.2039.37K