Following steps are involved in obtaining biogas:
(i) Mixing (slurry of cattle-dung and water).
(ii) Digesting (cattle-dung undergoing decomposition by anaerobic bacteria).
(iii) Formation of biogas (mixture of methane, CO2, H2, and H2S).
(iv) Spent slurry (residue left after the formation of biogas).
The process by which the biomass changes into biogas in the absence of air due to an anaerobic microorganisms is termed as an anaerobic decomposition.
