During sewage treatment, biogases are produced which include:

Options

A. Methane, oxygen, hydrogensulphide
B. Hydrogensulphide, methane, sulphur dioxide
C. Hydrogensulphide, nitrogen, methane
D. Methane, hydrogensulphide, carbon dioxide

Answer

**Step-by-Step Solution:**

1. **Understanding Sewage Treatment**: Sewage treatment involves the process of removing contaminants from wastewater, primarily from household sewage. This process is crucial for environmental protection and public health.

2. **Role of Anaerobic Bacteria**: During sewage treatment, anaerobic bacteria play a significant role. These bacteria thrive in environments devoid of oxygen and are essential for breaking down organic matter in sewage.

3. **Methanogenic Bacteria**: A specific group of anaerobic bacteria known as methanogens is responsible for producing biogas. These bacteria convert organic waste into methane and other gases through a process called anaerobic digestion.

4. **Biogas Composition**: The biogas produced during sewage treatment primarily consists of:
- **Methane (CH₄)**: The main component of biogas, which is a valuable energy source.
- **Carbon Dioxide (CO₂)**: Another significant component that is produced alongside methane.
- **Hydrogen Sulfide (H₂S)**: A gas that can be toxic and is produced in smaller quantities.
- **Hydrogen (H₂)**: This gas is also produced during the digestion process, although in lesser amounts.

5. **Conclusion**: Therefore, the biogases produced during sewage treatment include methane, carbon dioxide, hydrogen sulfide, and hydrogen.

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