Which one of the following is a device used to control particulate matter ?

Options

A. Arresters
B. Scrubbers
C. Filters
D. Electrostatic precipitator

Answer

To determine which device is used to control particulate matter, let's analyze the options provided: Arrestors, scrubbers, filters, and electrostatic precipitators.

1. **Understanding the Options**:
- **Arrestors**: These are typically used for safety measures, such as preventing the spread of fire or controlling debris, but they are not specifically designed for controlling particulate matter.
- **Scrubbers**: These devices are primarily used to remove gases and can also remove some particulate matter, but their main function is not focused on particulates.
- **Filters**: While filters can capture particulates, they are not as efficient as other specialized devices when it comes to large-scale removal of particulate matter from exhaust.
- **Electrostatic Precipitators**: These are specifically designed to remove particulate matter from exhaust gases. They can remove over 99% of particulate matter, making them highly effective.

2. **Functioning of Electrostatic Precipitators**:
- Electrostatic precipitators work by using high-voltage electrode wires that produce a corona discharge. This discharge releases electrons.
- The released electrons attach to dust particles, giving them a negative charge.
- These negatively charged dust particles are then attracted to positively charged collecting plates, allowing for the separation of dust from the air.

3. **Conclusion**:
- Among the options provided, the device that is most effective and widely used for controlling particulate matter is the **Electrostatic Precipitator**.

**Final Answer**: The device used to control particulate matter is **Electrostatic Precipitator**.

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