wat is d principle of biogas explain its working wid diagram

Biogas is obtained from the excretion of animals like cow dung and plant wastes.

Following is the composition of biogas:

Methane: 50% to 75%

Carbon dioxide: 25% to50%

Nitrogen: less than 10%

Hydrogen: less than 1%

Hydrogen disulphide: less than 3%

Diagram of biogas plant:

Working principle of biogas: In biogas, combustion of methane takes place in presence of oxygen which gives away heat and light.

CH₄ + 2O₂ => CO₂ + 2H₂O + heat + light