CODEL Energy Tech 401 Installation, Operation And Maintenance Manual page 20

EnergyTech 401
Operating and Maintenance Manual
Conversion factors (N)
2.2.4.3
2.2.4.4 Correction for oxygen
& water vapour
Page: 20
V =
The conversion factors for the analysers are given below :
CO Molecular mass (RMM) = 12 + 16 =
1 vpm
3
mg/m
SO Molecular mass (RMM) = 32 + 16 + 16
2
1 vpm
3
2.86 mg/m
NO Molecular mass (RMM) = 14 + 16 + 16
(equivalent) 1 vpm
3
2.05 mg/m
Legislation demands that all oxides of nitrogen be expressed as NO
It is not necessary to measure both NO and NO
particular processes, and typically is 95% NO; 5% NO
NO 1vpm
x
3
mg/m
The mass concentration present is calculated as below;
3
mg/m (STP) = N. vpm
This value is the mass concentration of the gas at STP.
Finally the effects of water vapour and oxygen need to be considered.
Since the vpm measurement is already normalised for temperature and pressure,
the only further normalisation required is for the dilution effects of water vapour
and oxygen. These are straightforward calculations as shown below;
3 3
mg/Nm = mg/m (STP) x
CODEL
Monitoring Solutions
22.4 (standard volume of an ideal gas)
28
= 28/22.4 =
=
= 64/22.4 =
=
= 46/22.4 =
as the relationship is fixed in
2
.
2
= 2.05 x (100%/NO%)
20.9 - 0% standard
2
20.9 - (0% measured) DRY
2
1.25
64
46
equivalent.
2
x 100
100 - H O%
2