Over 99% particulate matter present in the exhaust from thermal power plant can be removed by :-

Options

A. Scrubber
B. Electrostatic precipitor
C. Catalytic converter
D. lichen

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the method that can remove over 99% of particulate matter from the exhaust of a thermal power plant.

2. **Identifying the Options**: The options provided are rubber, electrostatic precipitator, catalytic converter, and lichens.

3. **Analyzing the Options**:
- **Rubber**: Not relevant for removing particulate matter from exhaust.
- **Electrostatic Precipitator**: This device is specifically designed to remove particulate matter from exhaust gases.
- **Catalytic Converter**: Primarily used for converting harmful gases into less harmful emissions, not specifically for particulate matter.
- **Lichens**: While they can absorb pollutants, they are not a method for removing particulate matter from exhaust.

4. **Choosing the Correct Answer**: The electrostatic precipitator is the most effective option for removing particulate matter from the exhaust of thermal power plants.

5. **Explanation of the Mechanism**:
- The electrostatic precipitator uses high-voltage electrode wires (around 12,000 volts) that create a corona discharge.
- This discharge releases electrons that attach to dust particles, giving them a negative charge.
- The negatively charged dust particles are then attracted to grounded collecting plates, effectively removing them from the exhaust.

6. **Final Answer**: Over 99% of particulate matter present in the exhaust from a thermal power plant can be removed by an **electrostatic precipitator**.

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