In a coal-fired power plant, electrostatic precipitators are installed to control the emission of

Options

A. `CO`
B. `SO_(2)`
C. `NO_(x)`
D. SPM

Answer

To solve the question regarding the purpose of electrostatic precipitators in a coal-fired power plant, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Purpose of Electrostatic Precipitators**:
- Electrostatic precipitators are devices used to remove particles from exhaust gases in industrial processes, including coal-fired power plants.

2. **Identifying the Emissions in Coal-Fired Power Plants**:
- Coal-fired power plants emit various pollutants, including gases like carbon monoxide (CO), sulfur dioxide (SO2), nitrogen oxides (NOx), and solid particles known as suspended particulate matter (SPM).

3. **Functioning of Electrostatic Precipitators**:
- These devices operate on the principle of electrostatic force. They consist of discharge wires and collecting plates.
- When a high voltage is applied, an electric field is created between the wires and the plates.

4. **Charging of Particles**:
- As the air containing dust and particulate matter passes through this electric field, the particles become charged.

5. **Collection of Charged Particles**:
- The charged particles are then attracted to the collecting plates, where they accumulate, effectively removing them from the air stream.

6. **Conclusion**:
- Since electrostatic precipitators are designed to capture solid particles, the primary emission they control is Suspended Particulate Matter (SPM), which includes aerosols and solid particles.

### Final Answer:
Electrostatic precipitators in a coal-fired power plant are installed to control the emission of **Suspended Particulate Matter (SPM)**.

---