Biomass gasification is basically conversion of solid Biomass (Wood, agriculture residues etc.) in to a combustible gas mixture normally called “Producer Gas” (or low Btu gas). The process involves partial combustion of Biomass. Partial combustion is carried out in absence of air or less air than the stroichiometric requirement of air for complete combustion.
Partial combustion produces Carbon Monoxide (CO) as well as hydrogen (H2) which are both combustible gas. Solid Biomass fuels, which are usually inconvenient and have low efficiency of utilization can thus be converted in to a high quality gaseous fuel with associated convenience etc.

System Equipment in which gasification of Biomass takes place is known as gasifier. There are three designs of gasifiers.

• Updraft
• Downdraft
• Crossdraft

In Indian market generally downdraft gasifiers are available due to utilization of mechanical mode. In this type air intake and bionmass is fed at the top. Biomass moves down as the process proceeds. The first stage consists of drying through pyrolysis oxidation and reduction. The hot gas coming out of the Gasifier has significant carry over of ash and soot particles. The gas is passed through cyclone and scrubber for cleaning and cooling. The clean and cool gas is than further passed through fine filter and fed into a diesel generating set to run the engine or for direct heat application. The diesel generating set operates on dual-fuel mode(typically 20% Diesel and 80% producer gas.)