Which among the following is not associated with sewage treatment plant?

Options

A. Biochemical Oxygen Demand
B. Formation of flocs
C. Activated sludge
D. Treatment through scrubber

Answer

To determine which option is not associated with a sewage treatment plant, let's analyze each option provided in the question step by step.

### Step-by-Step Solution:

1. **Understanding Sewage Treatment**:
- Sewage treatment plants are facilities designed to treat wastewater and sewage to remove contaminants and produce treated effluent that can be safely released into the environment or reused.

2. **Identifying Key Terms**:
- **Biochemical Oxygen Demand (BOD)**: This is a measure of the amount of oxygen that bacteria will consume while decomposing organic matter in water. It is a critical parameter in assessing water quality and is indeed associated with sewage treatment.
- **Formation of Phlogs**: Phlogs refer to the masses of bacteria that form in the treatment process. These bacteria help in breaking down organic materials, making this term relevant to sewage treatment.
- **Activated Sludge**: This is a process used in sewage treatment where a mixture of wastewater and microorganisms is aerated to promote the breakdown of organic matter. It is a crucial component of sewage treatment.
- **Treatment through Scrubber**: Scrubbers are devices used to remove pollutants from gases, particularly in air pollution control. They are not typically associated with sewage treatment, which deals with liquid waste.

3. **Conclusion**:
- Among the options provided, "treatment through scrubber" is not associated with sewage treatment plants. It is primarily related to air pollution control.

### Final Answer:
The option that is not associated with a sewage treatment plant is **treatment through scrubber**.

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