An electrostatic precipitator (ESP) is a filtration device that removes fine particles from a flowing gas through the use of an induced electrostatic charge. ESPs apply energy only to the particulate matter being collected, thus it is very efficient in its consumption of energy. This is a departure from typical processing applications which apply energy to the entire gas stream.
Electrostatic precipitators are best suited to a narrow band of applications, typically in exhaust and breathing air applications. Specific applications include the removal of dirt, oil mist, acid mist, sulfur, and bacteria. ESPs may be located in steam plants, blast furnaces, ventilation systems, and medical settings.
There are two primary types of precipitators: wet and dry. Both types of electrostatic precipitators have similar physical sizing considerations. Dry electrostatic precipators are best for larger particle removal (10 microns and above), whereas wet electrostatic precipitators are best suited for submicron applications. Generally speaking, dry ESPs are a control device to remove heavy particulate loads while wet ESPs act as a final polishing device.