Kane 905 - Calculated Efficiency and Excess Air Formulas

KANE905 Operators Manual Page 45
Where K3 = [(9 x H
2
+ H
2
O) / 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 losses + 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%
CO
2
% = [(20.9 - O
2
m) x K2 / 20.9]
Unburned fuel Loss % = K4 x CO / ( CO + CO
2
)
Note: CO scaled in %
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. This loss is subtracted
from the efficiency.
Oxygen Reference
CO(n) = CO x
(20.9 - O
2
r)
(20.9 - O
2
m)