M&C CG Series, Инструкция по эксплуатации

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N O T E !
High NO
2
-concentrations, especially in connection with high flow ratios
need higher operating temperatutres of the converter, in particular the
start up process of the maximum values.
N O T E !
High operating temperatures of the converter, especially the start up
process of the maximum values leads to an increased abrasion of con-
verter components, in particular sealing- and oven-components!
D AN G E R !
The maximum allowable operating temperature for catalyst type C is
380 °C [716 °F). Temperatures above 400 °C [752 °F] lead to a combus-
tion of the converter material. Urgent fire danger !
D AN G E R !
The maximum allowable operating temperature for catalyst type SS is
680 °C [1256 °F]. Temperatures above 680 °C [1256 °F]. can lead to a
destruction of the catalyst resp. converter!
8.3 CROSS SENSITIVITIES AND INFLUENCE OF INTERFERING/CARRIER GAS
From operating experiences in different applications as well as laboratory measurements with differrent
CG-converter- and catalyst types we got a lot of experiences about influencing factors on the NO
2
-NO
conversion process. The following hints make no claim to be complete, but can help choosing the ade-
quate catalyst type as well as give an indication for the integration of the CG-converter into a certain
system environment.
In practice, often several influencing factors have any effect at the same time. With their effect on the
NO
2
- conversion they are possibly interacting and therefore can complicate an explicit interpretation of
a certain device performance.
N O T E !
Carbon monoxide (CO)
In the conversion process from NO
2
to NO carbon monoxide is generated or
destroyed (oxydised). The hereby resulting CO-concentration downstream the
converter depends on: catalyst type, NO
2
-concentration, O
2
-concentration in
the sample gas and can be some 10 ppm.
Therefore, a CO-measurement should not be installed downstream the con-
verter but with a separate sample gas way to avoid faulty measurements.
N O T E !
Oxygen (O
2
)
In the conversion process, oxygen is generated proportional to the NO
2
con-
centration. This fact can lead to a faulty measurement in a downstream oxygen
trace measurement (ppm)!