Gasification converts organic material into fuel gas by heating it with a limited supply of oxygen.
The process transforms biomass such as wood chips, agricultural residues, or other carbon-rich materials at high temperature. Instead of fully burning the feedstock, gasification produces a combustible mixture called syngas, generally containing carbon monoxide, hydrogen, and sometimes methane, along with carbon dioxide and impurities.
After cleaning, syngas can be burned for heat or electricity, or processed into chemicals and liquid fuels. The composition depends on the feedstock, temperature, pressure, and gasifying agent. Tar, ash, and other contaminants must often be removed before engines or synthesis equipment can use the gas.
Gasification is different from anaerobic digestion, which uses microbes without oxygen and produces biogas. Fermentation makes fuels such as ethanol from sugars, while transesterification converts oils or fats into biodiesel.