Electrostatic precipitators are employed to remove particulate pollutants of the size of

Options

A. `5-20 mum `
B. `20 -50 mum`
C. `50 mum` and larger
D. `0.5-5.0 mum`.

Answer

To solve the question regarding the size of particulate pollutants that electrostatic precipitators are employed to remove, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Electrostatic Precipitators**:
- Electrostatic precipitators are devices used to remove particulate matter from air or gas streams. They operate on the principle of electrostatic attraction.

2. **Functionality of Electrostatic Precipitators**:
- These devices work by charging the dust particles in the air. When air containing particulate matter passes through the precipitator, a corona discharge generates negatively charged ions.

3. **Charging of Particulate Matter**:
- The negatively charged ions attach to the dust particles, giving them a negative charge. This process is crucial because it allows the particles to be attracted to a positively charged collection plate.

4. **Collection of Particulate Matter**:
- The charged dust particles are then attracted to and collected on the positively charged plates (anodes) within the precipitator, effectively removing them from the air stream.

5. **Size of Particulate Matter Removed**:
- Electrostatic precipitators are particularly effective at removing particulate matter in the size range of 5 to 20 micrometers (µm) in diameter. This range is significant because it includes many of the harmful pollutants that can affect human health and the environment.

6. **Conclusion**:
- Therefore, the correct answer to the question is that electrostatic precipitators are employed to remove particulate pollutants of the size of **5 to 20 micrometers**.

### Final Answer:
Electrostatic precipitators are employed to remove particulate pollutants of the size of **5 to 20 micrometers**.

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