Question

Write note on a typical biogas plant. How microbes help in production of biogas.

Answer 1

• Biogas is a mixture of gases (predominantly methane) produced by the microbial activity which may be used as fuel.
• Certain bacteria which grow anaerobically on cellulosic material produces a large amount of methane along with carbon dioxide and hydrogen.
• These bacteria are collectively called methanogens, and one such common bacterium is Methanobacterium.
• These bacteria are commonly found in the anaerobic sludge during sewage treatment.
  
• The biogas plant consists of a concrete tank (10-15 feet deep) in which bio-wastes are collected and a slurry of dung is fed.
• A floating cover is placed over the slurry, which keeps on rising as the gas is produced in the tank due to the microbial activity.
• The biogas plant has an outlet, which is connected to a pipe to supply biogas to nearby houses.