The major components of landfill gas are methane and carbon dioxide, which are colorless and odorless gases. The nasty smell at landfill field comes from some minor components, such as volatile aromatic compounds and sulfur-based compounds. Landfill gas typically consists of 50% -60% of methane, 40%- 50% of carbon dioxide and 1% of minor components.

Safe utilization of coal-bed gas (methane) is an integral part of comprehensive exploitation of coal mine resources, and also an important measurement to reduce the coal mine accidents. Pretreatment system for coal-bed gas, which incorporates the functions of dehydration, amplifying & stabilizing gas pressure and filtration, is a critical safeguard for the transportation of coal-bed methane at all gas power plants.

Biomass gas is a collectively name for gases brought out of anaerobic fermentation at sewage treatment plants, alcohol factories, farms and etc. Its major components are 50%-80% of methane and 20%-50% of the carbon dioxide, and the rest conclude water vapor, sulfide, nitride and other hundreds of gas components. In particular, hydrogen sulfide often reaches thousands or tens of thousands of PPM. Biomass gas is usually used at original site as heat or power source. At sewage treatment plants, alcohol factories and farms where biomass gas resources are rich, combined generation of coldness, heat and power (CHP) is often applied.