Thermal plants have installed

Options

A. cyclone collector
B. porous filters
C. electrostatic precipitators
D. adsorbents

Answer

### Step-by-Step Solution:

1. **Understanding the Function of Thermal Plants**:
- Thermal plants generate electricity by burning fossil fuels, which can produce particulate matter and other pollutants.

2. **Introduction to Electrostatic Precipitators**:
- To control pollution, thermal plants are equipped with devices called electrostatic precipitators (ESPs).

3. **Mechanism of Electrostatic Precipitators**:
- ESPs consist of electrostatic plates that are maintained at a very high voltage.
- As the flue gases containing dust particles pass through these plates, the particles become charged.

4. **Charging of Particulate Matter**:
- The dust particles acquire a negative charge and are referred to as "Corona particles."
- This charging process occurs due to the high voltage present on the plates.

5. **Movement and Collection of Particles**:
- The velocity of the gas flow through the ESP is kept low, allowing the charged particles to be attracted to the oppositely charged plates.
- As a result, the particles adhere to the plates, effectively removing them from the gas stream.

6. **Outcome of the Process**:
- The cleaned air, free from most particulate matter, is then released into the atmosphere.
- This process ensures that up to 99% of the particulate matter is removed from the emissions of thermal plants.

7. **Conclusion**:
- The correct answer to the question is that thermal plants have installed electrostatic precipitators to reduce air pollution.