Question

Describe the steps involved in obtaining biogas.

Answer 1

Hint:Biogas is formed of a mixture of methane, carbon dioxide, hydrogen and hydrogen sulphide. It mainly contains \[75\% \]methane. Therefore it is also used as a fuel as it burns without releasing any smoke and no residue is left after heating. Biogas can also be produced naturally at the bottom of oceans, rivers or lakes.

Complete step by step answer:
The mixture of all the components listed above is known as biomass. Following steps are involved in obtaining biogas:

-Mixing - The biomass is dumped in the biogas reactor to form slurry. In order to make slurry, water is also mixed with the biomass in adequate quantity.

-Digesting – The anaerobic bacteria then undergo anaerobic decomposition. In this decomposition, the micro organisms break down the biodegradable material in the absence of oxygen. The gases released during this process are collected in the gas chamber simultaneously and then released when required.

-The residue left in the rector has minerals like phosphorus and nitrogen. They are used as fertilisers for plants.

Note:It is important to remember that the biogas is also known as ‘gobar gas’. This is because the material required for the production of biogas is mainly cow dung. Biogas is a renewable source of energy because it can be produced and used again and again and does not produce carbon dioxide. It can be used as excellent fuel. Since the production of biogas involves methane, therefore it is also helpful in reducing greenhouse effect in the atmosphere.