Bentone BG 550 LN, Инструкция по установке и обслуживанию

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DETERMINATION OF GAS VOLUME FOR THE INSTALLATION
DETERMINATION OF GAS VOLUME FOR THE INSTALLATION
Specifi cations on natural gas, town gas and biogas vary. For more exact
information please contact the gas distributor.
Example how to calculate the gas volume (natural gas)
172 205 16-1 12-01
Net calorifi c value
Gas quality kWh/Nm
3
kJ/Nm
3
kcal/Nm
3
Natural gas 10.3 37 144 8 865
Propane 26.0 93 647 22 350
Butane 34.3 123 571 29 492
Town gas 4.9 17 653 4 213
Biogas 7.0 25 219 6 019
V = Gas volume Nm 3 /h
Q = Boiler output 120 kW
H
u
=
Calorifi c value of the gas A. 37 144 kJ/Nm
3
, B. 10.3 kWh/Nm
3
η
=
Expected effi ciency 90%
Ex. A v=
Q .3 600
=
120 . 3 600
≈
12,9 Nm
3
/h
H
u
·
η
37 144 . 0,90
Ex. B v=
120
≈
12,9 Nm
3
/h
10,3 · 0,90
If the barometer height, pressure and temperature of the gas deviate consi-
derably from the normal values this must be taken into account as follows:
f = 273+t . 1013,25
273 B+P
u
t = Temperature of the gas at the gas meter (15°C)
B = Barometer height (945 mbar)
P
u
= Pressure of the gas at the gas meter (15,0 mbar)
f = 273+15 . 1013,25
273 945+15
f = 11,1
The gas volume read on the gas meter actually reads
1,11
.
12,9 = 14,4 m
3
/h.