Electrostatics

Electrostatic Precipitator

What is it?

An electrostatic precipitator is a device that uses electrostatic forces to move particles out of a flowing gas stream and onto collector plates (US Environmental Protection Agency).

What does it do?

The purpose of electrostatic precipitators is to remove dust particles from harmful exhaust gases that are released from an industrial process. Matter created in the industrial process becomes dust and is carried in the hot stream of exhaust gases. The precipitator is designed to collect most of the dust and the exhaust travels through. This invention is used in many industries including the cement, chemical, metal, paper and power/electric industry. (Neundorfer)

How Does It Work?

An electrostatic precipitator utilizes the law of electrostatic charges, making the dust and liquid droplets develop a positive charge when they contact a strongly positively charged wire. The positively charged dust and droplets cause the collection plates to develop a negative charge. When the positive droplets and dust come in contact with the collection plates they develop a neutral charge and are collected in large containers called hoppers (ON Science 9.).
Learnology 101 - Electrostatic Precipitators

Electrostatic Precipitators collect 99.9% of dust from gas streams!

Disposal and Removal

The matter collected on the collection plates must be removed and cleaned out. This matter is removed by a “rapping mechanism”. The laden-gas used to clear out the collection plates must be flowing at an appropriate velocity and a fan as well as ductwork design must be created in order to generate the steady gas flow (Environmental Protection Agency).

References:

1. "1PPC - Electrostatic Precipitator Technology Page 1." PPC Industries - Electrostatic Precipitators. N.p., n.d. Web. 13 Feb. 2013. <http://www.ppcesp.com/brchpg1.html>.

2. "Particulates - Electrostatic Precipitators (ESPs) | Air Pollution Control Orientation Course | Air & Radiation | US EPA ." US Environmental Protection Agency. N.p., n.d. Web. 13 Feb. 2013. <http://www.epa.gov/eogapti1/course422

3. Neundorfer. "Electrostatic Precipitator KnowledgeBase"Neundorfer. Neundorfer, n.d. Web. 13 Feb 2013.

4. Environmental Protection Agency. "Electrostatic Precipitators" Electrostatic Precipitators. Environment Protection Agency, n.d. Web. 13 Feb 2013.

5.Blake, Leesa, Mazza, Micheal, Mills, Alex, Mustoe, Frank, Ross, Jim and Stiff, Thomas. ON Science 9. Whitby: McGraw-Hill Ryerson, 2009. Print.


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