Technologies in Health
-
Infrared Methane Gas Alarm Unit
Introduction
Methane gas is the most common of
the saturated hydrocarbons present in the atmosphere
and occurs in natural gas and gases from oil wells.
It is the principal product of organic decay in swamps
and marshes, the gas being set free by the action of
bacteria. This method of formation in nature has given
rise to the name "marsh gas". The natural
concentration of methane gas in atmospheric air is approximately
1.7 PPM.
Liquid methane is used in nuclear
industry for cooling of neutrons. Sewage sludge which
has been fermented by bacteria yields a gas containing
about 70 per cent methane and this is used as a liquid
fuel. Methane is used for making printers ink and paints.
It is also used in rubber industry for making motor
tyres etc. Since methane gas forms an explosive mixture
with air in the concentration range 5 - 15 percent,
it poses an explosion hazard. Therefore, it is imperative
to monitor its concentration in the working areas of
plants and to give a warning signal whenever the concentration
exceeds the safe limit. It is also required to initiate
a suitable corrective action for reducing the concentration.
Non Dispersive Infrared (NDIR) methane
gas alarm system developed at Trombay, BARC, is based
on the absorption of infrared energy by methane gas
molecules at their characteristic absorption band. The
extent of absorption of the infrared energy by the methane
gas molecules in the gas stream is proportional to the
amount of methane gas present in the air. Calibration
of the monitors is carried out using standard methane
gas mixtures prepared in the laboratory.
This technology is under evaluation.
Contact for
more information Head,
Technology Transfer & Collaboration Division,
Bhabha Atomic Research Centre,
Trombay, Mumbai - 400 085
Tel : 091-022-25505337/25593897
Fax : 091-022-25505151
E-mail : headttcd@barc.gov.in
