Gas Collection

We offer both passive and active gas collection systems.

Passive systems
Passive systems use gas collected in vertical and horizontal wells with a variety of pressures and gas concentrations present.

Active systems
Active systems that are well designed are generally the most effective way of collecting gas from vertical and horizontal gas wells. Vertical wells are generally 10-25 metres deep, depending upon the landfill depth and the available equipment. Wells are usually spaced at 15-50 metre intervals. Horizontal wells consist of an evacuated trench that is then backfilled with permeable gravel. Active gas collection systems create low pressure in the wells through pumps connected by pipeline systems which assist in gas collection.

All wells normally have valves to regulate gas flow and to provide a sampling port, to assess gas generation, composition and pressure.

Gas utilisation

Landfill gas is treated through combustion, which destroys the methane by splitting it into water vapour and carbon-dioxide. It is important that the combustion process does not lead to additional or harmful emissions and that it complies with the respective local environmental legislation. In Germany, for example, strict legislation is applied through the "TA-Luft" (Emission Control Act). Green Gas ensures that these requirements are met.

Green Gas offers two combustion options: Flaring and gas powered engines.

Gas-to-energy

With more than 200 plants built, representing an installed power of more than 150MW_el, Green Gas has the expertise to transform unwanted landfill gas into clean energy.

Our integrated solutions cover the entire system including gas collection equipment, flares and compressors, gas treatment and co-generation units. We provide control systems, transformers and grid connection to deliver an integrated solution. Our flexible technology is suited to variations in gas quantities and qualities. With a modular design, proven technology and excellent 24/7 service, Green Gas plants have high operational availabilities.