Electrostatic Precipitator

electrostatic precipitator

[i′lek·trə‚stad·ik prə′sip·ə‚tād· ər] (engineering) A device which removes dust or other finely divided particles from a gas by charging the particles inductively with an electric field, then attracting them to highly charged collector plates. Also known as precipitator.

Electrostatic Precipitator

a device used to remove liquid droplets or solid particles from an industrial gas by means of the ionization of the droplets or particles as the gas passes through a corona-discharge area and the subsequent precipitation of the droplets or particles on electrodes. In most cases, an electrostatic precipitator consists of a precipitator and a voltage source. The precipitator is a collecting chamber that contains corona-forming electrodes and collecting electrodes. The ionization area and the precipitation area may be either integrated or separated.

Electrostatic precipitators use only high-voltage (40-70 kilo-volts) direct current; the corona-forming electrodes are always connected to the negative terminal of the power supply. According to the state of the gas, electrostatic precipitators may be classified as wet or dry precipitators. In wet precipitators, the gas is saturated with moisture up to its dew point. According to the method of droplet or particle removal, a distinction is made between periodic and continuous precipitators. Electrostatic precipitators may operate at atmospheric pressure or at pressures above or below atmospheric pressure. The gas temperature may be as high as 500°C or even higher; the degree of gas cleaning may be as high as 99.9 percent.

Electrostatic precipitators are widely used to clean the flue gases of fossil-fuel-fired steam power plants. They are also used in, for example, ferrous and nonferrous metallurgy.