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KM9106 Operators Manual
64
Calculated data:
Tnet = Net Temperature
%
CO2 content in flue gas
% Dry Flue Gas losses
% Wet losses
% Unburned carbon loss
%
Efficiency
%CO2
= (20.9 - %O2m) x K2 / 20.9
Tnet
= Flue Temperature - Inlet Temperature
Dry flue gas loss
= 20.9 x K1n x (Tnet) / K2 x (20.9 - %O2m)
Wet loss
= 9 x %H2 + %H2O / Qgr x [2488 + 2.1Tf - 4.2 Ti]
simplified
= [(9 x %H2 + %H2O) / Qgr] x 2425 x [1 + 0.001 Tnet]
Wet loss
= K3(1+0.001xTnet)
Where K3
= [(9 x %H2 + %H2O) / Qgr] x 2425
Net Efficiency
= 100% - dry flue gas losses
= 100% - 20.9 x K1n x (Tnet) / K2 x (20.9 - % O
2
m)
Gross Efficiency
= 100% - {dry flue gas wet losses}
= 100% - [20.9 x K1g x (Tnet) / K2 x (20.9 - %O
2
m)]+
[K3 x (1 + 0.001 x Tnett)]
Excess Air
= [(20.9% / (20.9% - 0
2
m%)) – 1] x 100%
CO2%
= [(20.9% - O2m%) x K2% / 20.9%]
Unburned fuel Loss
= K4 x CO% / ( CO% + CO2% )
Where K4
= 70 for coke
= 65 for anthracite
= 63 for Bituminous coal
= 62 for coal tar fuel
= 48 for liquid petroleum fuel
= 32 for natural gas
The formula for K4 is based on the gross calorific value Qgr. To obtain the loss based
on net calorific value multiply by Qgr/Qnet. Since this loss is usually small this
conversion has been ignored.
Oxygen Reference
CO(n) = CO x
(20.9 - O
2
r)
(20.9 - O
2
m)