With growing request for alternative energy sources the energetically utilisation of biogas gains more and more in importance. Beside of the biogas production from agricultural products there is also the possibility to use gases from waste water plants or landfill deposits as a source for the generation of electrical energy.

Beside of the energetically usable components these gases contain more often trace amounts of harmful gases, which can lead to damages of the used power plants or generators during combustion.

Hydrogen sulphide and ammonia, natural by-products from the fermentation process, as well as halogenated volatile hydrocarbons (C/FHC) present as traces in the fermentation compounds lead during combustion to acid components in the exhaust gas (SO2/SO3, NOx, hydrogen chloride, hydrogen fluoride) and to corrosion of the metal parts in the generators.

Volatile silicium compounds, especially siloxanes, transform during combustion to silicium dioxide (quartz), forming a very abrasive medium for all moved parts in the generators. Effects of the co-combustion of the trace gases are shortened maintenance intervals and in the worst case drastically reduced power-on times of the generators.

Cleaning of the raw biogas, especially from the lower volatile substances, as the most common siloxanes are, can be achieved by filters of active charcoal. Volatile substances as significant amounts of aromatic hydrocarbons or natural volatile contents of plants as terpenes (for example limonene) have a negative effect on the usability of the active charcoal filters as they compete with the harmful gases on the filter material. Therefore it can be useful to determine this sort of trace components during biogas analysis too.