Supply of oxygen to the biogas plant will have

Options

A. (a) positive effect
B. (b) negative effect
C. (c) no effect
D. (d) none of these

Answer

### Step-by-Step Solution:

1. **Understanding Biogas Production**: Biogas is produced in a biogas plant through the anaerobic digestion of organic matter, primarily animal dung and agricultural waste. This process involves specific bacteria known as methanogens.

2. **Role of Methanogens**: Methanogens are microorganisms that thrive in anaerobic (oxygen-free) environments. They are responsible for breaking down organic material and producing biogas, which mainly consists of methane and carbon dioxide.

3. **Anaerobic Conditions**: The biogas production process requires strict anaerobic conditions. This means that the presence of oxygen must be avoided to ensure the optimal functioning of methanogens.

4. **Effect of Oxygen**: If oxygen is supplied to the biogas plant, it can disrupt the anaerobic conditions necessary for methanogens to thrive. Oxygen is toxic to these bacteria, which can lead to a decrease in biogas production.

5. **Conclusion**: Therefore, the supply of oxygen to a biogas plant will have a negative effect on the production of biogas, as it inhibits the activity of methanogens and can halt the anaerobic digestion process.

### Final Answer:
The supply of oxygen to the biogas plant will have a negative effect on biogas production.

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