Biomass Combustion Manoj

7/31/2019 Biomass Combustion Manoj

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COMBUSTION TABLE FOR SOLID AND LIQUID FUELS

Molar weight Analysis Oxygen

Cont g/mol g/kg mol/kg mol/kg

C 12.01 336.00 27.98 27.98

H2

2.02 45.50 22.52 11.26

O2 32.00 301.00 9.41 -9.41

N2 28.01 3.50 0.12

S 32.06 1.29 0.04 0.04

Ash ---- 12.71

Water 18.02 300.00 16.65

Sum: 1000.00 Sum O2: 29.87

Nitrogen in air 3.77 * O2 112.621161

Sum dry air 142.49 lot

Humid ratio in air:

Total theoretical air need lo 142.49

Theoretical gas amount go 179.94

Theoretical dry gas got 140.76

CO2dry= O2dry= 29.873

CO2odry m= 1.600

O2wet= m=

Nitrogen due to air in excess

Oxygen due to air in excess

Water in air excess

Total air need 227.99 l

Total dry air 227.99 lt

Total gas 265.43 g

Total dry gas 226.26 gt

ppm

mg/Nm^3 (0 C 1 atm)

mg/m^3 (Tfg C 1 atm)

Mass of gases (Real gas) kg/kg fuel

Mass of gases (Dry gas)

Conclusion (m3n means normal cubic meter at 0C and 1,013 ba

mol/kg m3n/kg

Theoretic dry air lot 142.49 3.19

Theoretical air lo 142.49 3.19

Real dry air lt 227.99 5.11

Real total air l 227.99 5.11

Calc of air excess factor gives m = 1.250

To get m3n/kg, multiply by molar volume 0.0224 m3n/mol

Fraction in real gas:

Fraction in dry gas:


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Method 1Fuel flow

Air to Fuel ratio with the given excess air

Flue gas flow at the given fuel burning rate

Density of flue gas at 0 C 1 atm

Flue gas flow at 0 C 1 atm

Density of flue gas at 96 C 1 atm

Flue gas flow at 96 C 1 atm

1 Actual flue gas flow

SO2 composition

SO2 flow rate

Method 2

Fuel flowAir to Fuel ratio with the given excess air

Flue gas flow at the given fuel burning rate

1 Actual flue gas flow

Ratio of SO2 mass/Flue gas mass

SO2 flow rate

Remarks

Method 2 is more accurate because it has no assu

FUEL CONSUMPTION AT MAXIMUM STEAM GENERATION

Boiler maximum steam generation at 8 barg & at 100 deg FW

Boiler thermal efficiency

GCV of fuel at dry condition

GCV of fuel at 33% moisture content

Maximum fuel consumption

Steam to fuel ratio at 8 barg & at 100 deg C

Flue gas volumetric flow at maximum steam generation

(Note: This flue gas flow is assumed to be without Ash as after scrubber is

Duct size

Equivalent diameter

Flue gas velocity

Reynolds number calculation

Flue gas temperature

Velocity

Equivalent diameter


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Re = VelocityxDiameter/Kinematic Vi

Kinematic viscosity of flue gas at this temperature

Reynolds number through duct

Conclusion: Flow is highly turbulent

Reynolds number through chimney

Chimney diameter

Velocity through chimney

Kinematic viscosity of flue gas temperature (assumed 10 deg C temperatur

Considered temperature

Kinematic viscosity




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FUEL : FIRE WOOD + SAW DUST

Fuel:

Flue gases (mol/kg)

H2O CO2 N2 SO2 O2 Ar

27.98

22.52

0.12

Adjusted for measured SO2 0.040

Adjusted for sum 1000

16.65

39.17 27.98 0.12 0.04 0.00 0.00

112.621

39.17 27.98 112.75 0.040 0.00

67.57

17.92

0.00

39.17 27.98 180.32 0.040 17.92

1230.97

(CO2 mass per kg of Fuel)

0.148 0.105 0.679 0.0002 0.068

0.124 0.797 0.0002 0.079

178

(NERD report value) 508

376

7.56 0.705 1.231 5.049 0.00257 0.574

r)

mol/kg m3n/kg fuel

Theoretic dry gas got 140.76 3.15

Theoretical gas go 179.94 4.03

Real dry gas gt 226.26 5.07

Real total gas g 265.43 5.95


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1,583 kg/hr (Avg: 290 kg/hr fuel consumption at 30% MC (wet))

6.57 kg air/kg fuel

11,993 kg/hr

3.331 kg/s

1.272 kg/m 3

2.619709487 Nm 3/s

0.94085374 kg/m^3

3.54092601 m^3/s

3.54092601 m^3/s At 96 deg C and 1.013 bar

375.682 mg/m^3 of flue gas

4.789 kg/hr

1,583 kg/hr (Avg: 290 kg/hr fuel consumption at 30% MC (wet))6.57 kg air/kg fuel

11,993 kg/hr

11993 kg/hr

0.00257 kg SO2/kg of fuel

4.075 kg/hr

ption such as ideal gas and density conversion

6000 kg/hr

74.00% Gross basis

18 MJ/kg

12.06 MJ/kg

1583.299718 kg/hr

3.78955414 kg/kg

3.54092601 m3/s

onsidered)

0.620x0.620 mxm

.678 m http://www.engineeringtoolbox.com/equivalent-diamete

9.211566103 m/s

96 deg C

9.211566103 m/s

.678 m


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scosity

0.0000204 m^2/s http://www.firecad.net/Boiler-Calculations/Boiler-Exhau

306,149

1 m

4.508447021 m/s

drop due to uninsulated duct)

86 deg C

0.0000194 m^2/s http://www.firecad.net/Boiler-Calculations/Boiler-Exhau

232,394


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r-d_205.html


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stGas-Properties.aspx

stGas-Properties.aspx


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COMBUSTION TABLE FOR SOLID AND LIQUID FUELS

Molar weight Analysis Oxygen

Cont g/mol g/kg mol/kg mol/kg

C 12.01 336.00 27.98 27.98

H2

2.02 45.50 22.52 11.26

O2 32.00 301.00 9.41 -9.41

N2 28.01 4.20 0.15

S 32.06 0.23 0.01 0.01 Adjusted for measured SO2

Ash ---- 13.07 Adjusted for sum 1000

Water 18.02 300.00 16.65

Sum: ###### Sum O2: 29.84

Nitrogen in air 3.77 * O2 112.4968662

Sum dry air 142.34 lot

Humid ratio in air:

Total theoretical air need lo 142.34

Theoretical gas amount go 179.80

Theoretical dry gas got 140.63

CO2dry= O2dry= 29.840

CO2odry m= 2.650

O2wet= m=

Nitrogen due to air in excess

Oxygen due to air in excess

Water in air excess

Total air need 377.19 l

Total dry air 377.19 lt

Total gas 414.66 g

Total dry gas 375.49 gt

ppm

mg/Nm^3 (0 C 1 atm) (NERD report value)

mg/m^3 (Tfg C 1 atm)

Mass of gases (Real gas) kg/kg of fuel 11.86

Mass of gases (Dry gas)

Conclusion (m3n means normal cubic meter at 0C and 1,013 bar)

mol/kg m3n/kg

Theoretic dry air lot 142.34 3.19

Theoretical air lo 142.34 3.19

Real dry air lt 377.19 8.45

Real total air l 377.19 8.45

Calc of air excess factor gives m = 1.250

To get m3n/kg, multiply by molar volume 0.0224 m3n/mol

Fraction in real gas:

Fraction in dry gas:


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Method 1Fuel flow 1,674

Air to Fuel ratio with the given excess air 10.88

Flue gas flow at the given fuel burning rate 19,881

5.522

Density of flue gas at 0 C 1 atm 1.277

Flue gas flow at 0 C 1 atm 4.323654924

Density of flue gas at 105 C 1 atm 0.922457832

Flue gas flow at 105 C 1 atm 5.986599126

1 Actual flue gas flow 5.986599126

SO2 composition 40.600

SO2 flow rate 0.875

Method 2

Fuel flow 1,674Air to Fuel ratio with the given excess air 10.88

Flue gas flow at the given fuel burning rate 19,881

1 Actual flue gas flow 19881

Ratio of SO2 mass/Flue gas mass 0.00046

SO2 flow rate 0.773

Remarks

Method 2 is more accurate because it has no assumption such as

FUEL CONSUMPTION AT MAXIMUM STEAM GENERATION

Boiler maximum steam generation at 8 barg & at 100 deg FW 6000

Boiler thermal efficiency 70.00%

GCV of fuel at dry condition 18

GCV of fuel at 33% moisture content 12.06

Maximum fuel consumption 1673.773987

Steam to fuel ratio at 8 barg & at 100 deg C 3.584713376

Flue gas volumetric flow at maximum steam generation 5.986599126

(Note: This flue gas flow is assumed to be without Ash as after scrubber is considered)

Duct size 0.620x0.620

Equivalent diameter .678

Flue gas velocity 15.5738791

Reynolds number calculation

Flue gas temperature 105

Velocity 15.5738791

Equivalent diameter .678


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Re = VelocityxDiameter/Kinematic Viscosity

Kinematic viscosity of flue gas at this temperature 0.0000220

Reynolds number through duct 479,959



Chimney diameter 1

Velocity through chimney 7.622374745

Kinematic viscosity of flue gas temperature (assumed 10 deg C temperature drop due to unin

Considered temperature 95

Kinematic viscosity 0.0000210

Reynolds number through chimney 362,970



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FUEL : STP SLUDGE + SAW DUST

Fuel:

Flue gases (mol/kg) Considered composition dry basis

H2O CO2 N2 SO2 O2 Ar

27.98 48.0000% C

22.52 6.5000% H

43.0000% O

0.15 0.6000% N

0.007 0.0330% S

1.8670% Ash

16.65 100.0000%

39.17 27.98 0.15 0.01 0.00 0.00

112.497

Theoretical weight of flue gas

5.0906587 kg/kg of fuel

39.17 27.98 112.65 0.007 0.00 5.3567096 kg/kg of fuel (Calculat

Theoretical air requirement

4.1047928 kg of air / kg of fuel

4.1 kg of air/ kg of fu

185.62

49.24

0.00

39.17 27.98 298.27 0.00721 49.24 11.867613 kg/kg of fuel

1230.97 12.353535 kg/kg of fuel (Calculat

(CO2 mass per kg of Fuel)

0.094 0.067 0.719 0.00002 0.119 Real air requirement at the

0.075 0.794 0.00002 0.131 10.8777 kg of air/ kg of fu

19

55

41

0.705 1.231 8.351 0.00046 1.576

mol/kg m3n/kg fuel

Theoretic dry gas got 140.63 3.15

Theoretical gas go 179.80 4.03

Real dry gas gt 375.49 8.41 P=Ro.R.T

Real total gas g 414.66 9.29


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kg/hr (Avg: 290 kg/hr fuel consumption at 30% MC (wet))

kg air/kg fuel

kg/hr

kg/s

kg/m^3

Nm^3/s

kg/m^3

m^3/s

m^3/s At 96 deg C and 1.013 bar

mg/m^3 of flue gas

kg/hr

kg/hr (Avg: 290 kg/hr fuel consumption at 30% MC (wet))kg air/kg fuel

kg/hr

kg/hr

kg SO2/kg of fuel

kg/hr

ideal gas and density conversion

kg/hr

Gross basis

MJ/kg

MJ/kg

kg/hr

kg/kg

m3/s

mxm

m http://www.engineeringtoolbox.com/equivalent-diameter-d_205.html

m/s

deg C

m/s

m


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m 2/s http://www.firecad.net/Boiler-Calculations/Boiler-ExhaustGas-Properties.aspx

m

m/s

ulated duct)

deg C

m 2/s http://www.firecad.net/Boiler-Calculations/Boiler-ExhaustGas-Properties.aspx


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d from molecular weight and density)

l

d from molecular weight and density)

given excess air

l

Biomass Combustion Manoj

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