In a STP, microbial flocs are formed in

Options

A. Anaerobic sludge digester
B. Primary treatment
C. Aeration tank
D. Physicochemical treatment

Answer

**Step-by-Step Solution:**

1. **Understanding STP**: A Sewage Treatment Plant (STP) is designed to treat wastewater and sewage. It involves several processes to remove contaminants and produce an effluent that can be safely released into the environment.

2. **Identifying Microbial Flocs**: Microbial flocs are aggregates of microorganisms that form in wastewater treatment processes. They play a crucial role in the biological treatment of sewage by breaking down organic matter.

3. **Examining Treatment Stages**:
- **Anaerobic Sludge Digester**: This stage involves anaerobic bacteria that thrive in the absence of oxygen. It primarily breaks down complex organic substances but does not form microbial flocs.
- **Primary Treatment**: This is the initial stage of sewage treatment where larger solids are removed. It does not involve the formation of microbial flocs.
- **Aeration Tank**: This is where aerobic bacteria are introduced into the wastewater. In this tank, microbial flocs are formed as the aerobic bacteria aggregate to break down organic material. This is the key stage for microbial floc formation.
- **Physicochemical Treatment**: This involves chemical processes and does not contribute to the formation of microbial flocs.

4. **Conclusion**: The correct answer is that microbial flocs are formed in the **Aeration Tank** of the STP.

**Final Answer**: In a STP, microbial flocs are formed in the **Aeration Tank**.

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