Producer gas is a low calorific value fuel gas comprising of mainly carbon monoxide, hydrogen and nitrogen. It is produced by passing air or a mixture of air and steam through a burning bed of solid fuel such as, coal, coke, wood or biomass. Hydrogen is also present in a significant amount in the producer gas. The exact composition of producer gas depends on the type of fuel, composition of the blast and operating condition. Producer gas is formed in a gasifier.