Electrostatics

Electrostatic Precipitator

What are Electrostatic Precipitators?

An electrostatic precipitator is a device that uses electrostatics in order to clean the air of dust particles and liquid droplets. They are made in a variety of sizes ranging from small home-based ones, to large industrial truck-sized machines that purify all outgoing emissions on power plants. Although large industrial precipitators play a major role in decreasing air pollution, home-based precipitators also serve an crucial role in cleaning the house of allergens and other illness causing pollution.

How Does it Work?

An electrostatic precipitator works in several stages.


Stage 1: Once the dirty air enters the machine, it passes through the first filter stage which removes any large particles from the air.


Stage 2: The particles that come through then get ionized using rods that are charged from a power supply such as a power grid.


Stage 3: As the charged particles continue moving in the machine, they begin to be attracted by the collector plates due to the machine's application of the law of electrostatics that unlike charges attract.


Stage 4: In the last stage, any particles that did not settle in the collector plates get filtered using a fine filter. The efficiency of this machine is reported to be 99.5% (Plasma Clean).


The video below is a very good representation of how the electrostatic precipitator works.

Electrostatic Precipitator System Working.avi

How it uses Electrostatics

In the ionizing section there is a metal grid which gives the contaminent particles either a positive or negative charge (depending on the type of precipitator). As the particles enter stage three, they are attracted to the collecting plates of opposite charge.


Since unlike charges attract, the particles then begin to accumulate on the opposite charged plates. However, once they contact the plates, charging by contact occurs which causes the particles to lose their charge and no longer become attracted to the collecting plates. The particles then fall down into the hoppers which are routinely cleaned for residue.


In other types of electrostatic precipitators, the collector plates contain no charge and are connected with the ground that is neutral. When the charged particles come in contact with the collector plates, they are then grounded and become neutral by either losing or gaining electrons. Once again, the particles then fall down into the hoppers.



Importance

An electrostatic precipitator is an important device for several reasons.


In a home-based environment, it serves a purpose of purifying the air and removing any contaminants within the house.


On the other hand, in an industrial environment it helps make the factory more eco-friendly. The electrostatics precipitator purifies the emissions from a factory and removes potentially hazardous particles from it.


This is very important to do since there is an ever increasing amount of asthma cases which are linked with air pollution. By reducing air pollution through the electrostatic precipitators, one can help make the air more healthy for our bodies wether it be on a large scale or a home-based environment.


To provide a general overview, below are several different kinds of electrostatics precipitators.



Citations

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2013. <http://www.bbc.co.uk/schools/gcsebitesize/science/add_aqa_pre_2011/electricity/staticelectrev2.shtml>.


"How Electrostatic Precipitators Works." BPA Air Quality Solutions. BPA, n.d. Web. 20

Feb. 2013. <http://www.breathepureair.com/electrostatic-precipitators.html>.



"J2-15: Electrostatic Smoke Precipitator." Physics. N.p., n.d. Web. 20 Feb. 2013.

<http://www.physics.umd.edu/lecdem/services/demos/demosj2/j2-15.htm>.


"Electrostatic Precipitators." Plasma Clean. N.p., n.d. Web. 20 Feb. 2013.

<http://www.plasma-clean.com/index.php/products/electrostatic-precipitators>.


Blake, Leesa. On Science 9. Toronto, ON: McGraw-Hill Ryerson, 2009. Print.


โอโจ้ ปานสนาม. Electrostatic Precipitator Working. Rec. 1 Mar. 2013. N.d. CD.


"Uses of Electrostatics." BBC Schools. British Broadcasting Corporation, 2013. Web. 19

Feb. 2013.

<http://www.bbc.co.uk/schools/gcsebitesize/science/add_ocr_gateway/radiation/electrostaticsusesrev1.shtml>.


"Electrostatic Precipitator KnowledgeBase." Neundorfer Particular Knowledge.

Neundorfer, n.d. Web. 19 Feb. 2013.

<http://www.neundorfer.com/knowledge_base/electrostatic_precipitators.aspx>.


"Operation of Electrostatic Precipitators." Yosemite. US Government, n.d. Web. 20 Feb. 2013. <http://yosemite.epa.gov/oaqps/eogtrain.nsf/fabbfcfe2fc93dac85256afe00483cc4/bbd8958eb8fbeeea85256da3005cc39d/$FILE/SI%20445_10.pdf>.