In the process of treating sewage and industrial waste waters using air and a biological floc, the sediment obtained is called

Options

A. Activated sludge
B. Biogas
C. Bear
D. Wine

Answer

To solve the question regarding the sediment obtained in the process of treating sewage and industrial waste waters using air and a biological floc, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Process**:
- The treatment of sewage and industrial wastewater typically involves two main stages: primary treatment and secondary treatment.

2. **Identifying the Types of Organisms Used**:
- In the secondary treatment, biological organisms are used. These organisms can be either anaerobic (without oxygen) or aerobic (with oxygen).

3. **Recognizing Biological Floc**:
- A biological floc is a mass of microorganisms that clump together. This floc plays a crucial role in the secondary treatment process as it helps in the breakdown of organic matter.

4. **Sediment Formation**:
- After the secondary treatment, the biological floc settles at the bottom of the treatment tank, forming a sediment.

5. **Naming the Sediment**:
- The sediment that is formed at the end of the secondary treatment process is specifically known as "activated sludge."

6. **Choosing the Correct Option**:
- Among the given options:
- Option 1: Activated sludge
- Option 2: Biogas
- Option 3: Veal
- Option 4: Swine
- The correct answer is **Option 1: Activated sludge**.

### Final Answer:
The sediment obtained in the process of treating sewage and industrial waste waters using air and a biological floc is called **activated sludge**.

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