What gases are produced in anaerobic sludge digesters :-

Options

A. Methane and `CO_2` only
B. Methane, Hydrogen Sulphide and `CO_2`
C. Methane, Hydrogen Sulphide and `O_2`
D. Hydrogen Sulphide and `CO_2`

Answer

**Step-by-Step Solution:**

1. **Understanding Anaerobic Sludge Digesters**: Anaerobic sludge digesters are systems used to treat wastewater and organic waste through anaerobic digestion, a process where microorganisms break down organic matter in the absence of oxygen.

2. **Role of Methanogens**: The primary microorganisms involved in anaerobic digestion are methanogens, which are a type of archaea. These bacteria thrive in anaerobic conditions and are responsible for converting organic materials into methane and other gases.

3. **Gases Produced**: During the anaerobic digestion process, several gases are produced:
- **Methane (CH4)**: This is the main product of methanogenic bacteria and is the primary component of biogas.
- **Carbon Dioxide (CO2)**: Another significant gas produced during the digestion process.
- **Hydrogen Sulfide (H2S)**: This gas can also be produced, particularly when sulfur-containing compounds are present in the organic material being digested.

4. **Conclusion**: Therefore, the gases produced in anaerobic sludge digesters include methane, carbon dioxide, and hydrogen sulfide. The main gas of interest, especially for energy production, is methane.

**Final Answer**: The gases produced in anaerobic sludge digesters are methane (CH4), carbon dioxide (CO2), and hydrogen sulfide (H2S).

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