Methanator; Methanator Function - Siemens Maxum II Service Manual

4.7

Methanator

4.7.1

Methanator Function

The methanator is used with a Flame Ionization Detector (FID) when it is necessary to detect
carbon dioxide (CO
changed to methane using excess hydrogen and a catalytic reaction. The concentration of
methane, which can be detected using an FID, is proportional to the concentration of CO
CO. In this manner, it is possible to detect CO
The methanator design consists of a stainless steel tube that is filled with a catalyst. The tube
is heated using a heater cartridge, and an RTD temperature sensor and control circuit regulates
the temperature. The tube is heated to approximately 400°C and the sample with hydrogen
carrier is passed through the tube. The CO
are converted into methane for detection by the FID.
Two versions of the methanator exist for use in the Maxum edition II. The original is protected
by purging/pressurization. The more recent version is protected in an explosion proof
enclosure. Both versions are installed in the detector compartment of the Maxum II Airbath/
Airless Oven configuration.
Features of Both Methanator Models
As protection measure, the gas inlets and outlets that enter and leave the methanator are
configured as flame arrestors. In addition, both versions of the methanator assembly are
insulated to prevent the surface temperature of the methanator from exceeding 180°C.
Surface temperatures for the explosion proof/flameproof methanator are significantly lower
than 180°C.
NOTICE
Installation of a Methanator restricts the temperature range of the analyzer
The ambient temperature operating range of a methanator-equipped analyzer is
0°C≤T
Maxum Edition II Detectors
Service Manual, May 2018, A5E42019847001
) or carbon monoxide (CO). In the methanator CO
2
≤+50°C.
a
, CO and other types of gases using an FID.
2
and/or CO (depending on the exact temperature)
2
Flame Ionization Detector
4.7 Methanator
and CO are chemically
2
and
2
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