Bentone BG 450, Installation And Maintenance Instruction

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Bentone
T = Temperature of gas at the gas meter [°C]
B = Barometer reading [mbar]
P = Pressure of gas at the gas meter [mbar]
f = Factor calculated for multiplication with flow in Nm 3 /h to
arrive at actual flow in Nm 3 /h.
V = Actual flow [m 3 /h]
f =
273
·
B+P
273+T 1013.25
Example A
V
0A
= Q . 3600
=
160 · 3600
≈ 18.8 Nm 3 /h
H
u
·
η
34020 · 0.90
Example B
V
0B
= Q
≈
160
≈ 19 Nm 3 /h
H
u
·
η
9.5 · 0.90
Example C
V
0C
=
Q
=
160
≈ 19 Nm 3 /h
H
u
· 0,00116 ·
η
8126 · 0.00116 · 0.90
If the barometer reading (altitude), pressure and temperature of the gas
deviate significantly from normal values, this must be taken into account as
follows:
Calculation example:
Q = 160 kW
H
U
= Example A: 34020 MJ/Nm 3
Example B: 9.5 kWh/Nm 3
Example C: 8126 kcal/Nm 3
η =
90%
V
0
= Desired quantity of gas [Nm 3 /h]
Q = Boiler output [kW]
H
U
= Gas heat value [kWh/Nm 3 ] or [MJ/Nm 3 ] or [kcal/
Nm3]
η
=
Boiler efficiency [%]
6.7.1 Example of how to calculate the gas quantity
(natural gas G20):