Question

In the context of air pollution control, what is the primary function of an electrostatic precipitator?

1. Increasing the concentration of harmless gases in industrial emissions.
2. Removing over 99% of particulate matter from the exhaust of thermal power plants.
3. Converting unburnt hydrocarbons into carbon dioxide and water.
4. Facilitating the absorption of harmful gases using a spray of water or lime.

• A. All
• B. 2 only
• C. 3 only
• D. 4 only

Answer 1

Answer:

B. 2 only

Electrostatic precipitators

• Electrostatic precipitators are devices used for controlling air pollution, specifically for removing particulate matter from industrial emissions, particularly from thermal power plants.
• The primary function of an electrostatic precipitator is to efficiently capture and remove over 99% of particulate matter present in the exhaust from industrial processes.
• Electrostatic precipitators consist of electrode wires that are maintained at several thousand volts.
• The high voltage applied to the electrode wires produces a corona discharge, releasing electrons.
• These released electrons attach to dust particles in the exhaust, giving them a net negative charge.
• Grounded collecting plates are then used to attract the charged dust particles.
• The velocity of the air between the plates must be low enough to allow the dust to fall, separating it from the air stream.