UEi Test Instruments KM940 - Manual (Page 34)

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C. CALCULATION OF FUEL DATA
For any fuel not specified by Kane International the net calorific value, gross calorific value
and composition should be obtained from the fuel supplier.
The following fuel data has been calculated with reference to the efficiency calculation.
Example 1:
Chemical composition:
C 25%
H
2
3%
H
2
O 50%
Q
net
8.35 MJ/kg
Q
g
9.3 MJ/kg *
Max CO
2
20.4%
K1n = (255 x % carbon in fuel) / Q
net
(kJ/Kg)
= (255 x 25) / 8350 = 0.763
K1g = (255 x % carbon in fuel) / Q
g
(kJ/Kg)
= (255 x 25) / 9300 = 0.685
K2
= Max % CO
2
= 20.40
K3
= Wet Loss = [(9 x %H
2
+ %H
2
O) / 9300] x 2425
= [(9 x 3 + 50) / 9300] x 2425
= (77 / 9300) x 2425 = 20.08
K4 =
65 (an approximation for wood) *
The fuel values to program into the Analyser are as follows:
NATURAL GAS
K1g
K_2
K_4 : 0.763
: 20.4
: 65 K1n
K_3
O2r : 0.685
: 20.08
: 8.0
* Assumed values in the absence of supplied data. See previous appendix for other fuels.