Question

Name the part of a biogas plant where reactions take place in the absence of oxygen.

Answer 1

The biogas plant has a dome like structure built with bricks. A slurry of cow dung, vegetable wastes, crop residues etc is mixed with water and made into a slurry, and fed into the digester. The digester is a sealed chamber in which there is no oxygen. Anaerobic microorganisms that do not require oxygen decompose or break down complex compounds of the cow dung to generate gases like methane, $C{O}_2$, hydrogen and hydrogen sulphide. The bio gas gets stored in the gas tank above the digester from which they are drawn through pipes for use.