Question

Consider the following statements in respect of electrostatic precipitators:

1. Power requirement is very small compared to other air pollution control devices and so they are cheaper to perform than other devices.

2. Can handle both gases mists for high volume flow.

3. Very small particles can be collected either wet or dry.

Which of the above statements are correct?
1. 1 and 2 only
2. 2 and 3 only
3. 1 and 3 only
4. 1, 2 and 3

Answer 1

Correct Answer - Option 2 : 2 and 3 only

Concept:

Electrostatic precipitators (ESP):

• In electrostatic precipitators, the flue gas is made to pass through a highly ionised zone, where the particles get electrically charged and are separated out from the gas, with the help of electrostatic forces in the power full electric field.
• They are widely used in Thermal power plants, Pulp and Paper industries, Mining and Metallurgical industries, Iron and Steel plants, Chemical industries, etc.
• The main two advantages of ESP are particles may be collected wet or dry and efficiency more than 99% can be achieved.
• ESP can handle both gases and mists for high volume flow and even very small particles can be removed.
• It uses very high voltage to generate powerful electric field. Hence, power consumption is very high and subsequently ESP are very costly as compared to other air pollution control devices.  

Hence, statement 1 is incorrect, rest two statements are correct.