Smell Gas?
Original article date: January 2000
Don’t rely on your nose! There are many reasons why gas analysis should be undertaken, but it is often overlooked. Dr STEPHEN FIRTH of Servomex explains
Gas analysis has a huge range of applications in industry. Gas analysers are, for example, used to ensure that combustion process emissions are within the regulations set (in the UK) by the Environment Agency and by similar organisations throughout the industrialised world.
Industrial gas manufacturers operating air separation processes have an obvious need to ensure that their products are pure and fall within the specifications expected by their customers, so monitor their nitrogen (for example) to ensure that it does not contain oxygen. Chemical processes which have the potential either to be explosive or to liberate toxic material are closely monitored by appropriate gas analysers to ensure that nothing untoward takes place. Surprisingly, many systems installed in industry for applications which have a process monitoring and/or safety requirement are supplied without the gas analysis equipment which can meet that need. It is frequently left to the end user to approach gas analyser manufacturers and arrange for a suitable system to be installed.
This is presumably because OEM process systems manufacturers sometimes see gas analysis as being too specialised for them and prefer not to undertake responsibility for process and safety monitoring.
However, the leading manufacturers of gas analysis equipment are quite happy to work with OEM systems suppliers and supply the expertise required on a partnership basis. Major world-class companies like the Servomex Group maintain invaluable libraries of the legislative requirements of all the key industrial countries and are able reliably to supply gas analysis systems which meet those requirements.
Recent advances in gas analyser technology, notably in the size and sensitivity of the transducers employed within the instruments, have greatly extended the capability of gas analysis. An advanced new range of gas analysers for environmental monitoring and the industrial gases industry just launched by Servomex can, for example, achieve % level measurement of the constituents of blended gases and, in another variant designed for producers of hydrogen, measure trace levels of CO, CO 2 or methane as contaminants within hydrogen.
The new transducer technologies also make it possible in some cases for four separate transducers to be installed in one standard 19in wide 3U rack-mounted analyser. This gives much greater breadth of analysis from a single instrument and the key ability to make more than one gas measurement simultaneously. Transducers available for the new Servomex analysers include the Zr703 non-catalytic oxygen sensor and the paramagnetic transducer Pm1158. The new environmental gas analyser of the range has transducers available for the measurement of trace levels of CO, NO and SO 2 and can also measure % level CO and % levels of O 2 .
OEM systems manufacturers should look again at increasing the value of their service to their customers by providing safety and environmental gas analysis systems as part of their overall package. New technologies and the readily available support of the major specialists in gas analysis have made it even more sensible to relieve their customers of the need to organise gas monitoring and analysis systems for themselves.
For those OEMs who are unfamiliar with the various technologies associated with gas analysis, Servomex has written an extremely readable guide entitled Principles of Gas Analysis. This is illustrated with colour diagrams and starts with a summary of the four main gas analysis techniques – the paramagnetic, Zirconia, Photometric and thick-film technologies – and then goes into more depth in the rest of the guide.
- Servomex
January 2000