Question

Biogas production occurs under

• A. Aerobic conditions
• B. Anaerobic conditions
• C. High oxygen pressure
• D. UV radiation

Hint:

Remember: \[ \boxed{\text{Organic Waste} \longrightarrow \text{Anaerobic Digestion} \longrightarrow \text{Biogas (CH}_4+\text{CO}_2)} \] Methanogenic bacteria require the complete absence of oxygen to produce biogas.

Answer 1

The Correct Option is B

Concept: Biogas is a renewable fuel produced when microorganisms decompose organic matter in the complete absence of oxygen. The process is known as anaerobic digestion. The major component of biogas is methane, which serves as an excellent fuel for cooking, heating, and electricity generation.

Step 1: Understand anaerobic digestion.
Organic wastes such as:
• Cow dung
• Sewage sludge
• Agricultural residues
• Food waste are decomposed by anaerobic microorganisms.

Step 2: Composition of biogas.
Typical biogas contains:
• Methane (50--70%)
• Carbon dioxide (30--45%)
• Small amounts of hydrogen sulphide and water vapour. Methanogenic bacteria such as Methanobacterium produce methane during the final stage of anaerobic digestion.

Step 3: Eliminate incorrect options.

• Aerobic conditions prevent methane formation.
• High oxygen pressure inhibits methanogenic bacteria.
• UV radiation has no role in biogas production.
• Biogas production occurs only under anaerobic conditions. Final Answer: \[ \boxed{Option (B) is correct \]