Wet Electrostatic Precipitator is a kind of new dust removal equipment, which can be used to deal with trace dust and micro particles. Wet Electrostatic Precipitator was first popularized by F.G.Cottrell in 1907. Now, it is mainly used in coal-fired power plant. First dry ESP was 1922 at Detroit Edison.
A wet electrostatic precipitator (WESP or wet ESP) operates with water vapor saturated air streams (100% relative humidity). WESPs are commonly used to remove liquid droplets such as sulfuric acid mist from industrial process gas streams. The WESP is also commonly used where the gases are high in moisture content, contain combustible particulate, or have particles that are sticky in nature.
Basic mechanism of collecting particulate matter (PM) of Wet Electrostatic Precipitator (WESP) is the same as that of Dry Electrostatic Precipitator (DESP), while the collected PM is removed by washing water in WESP, instead of impact force of rapping used in DESP.

Global wet electrostatic precipitator market was valued at 565 Million US$ in 2018 and is projected to reach 794 Million US$ by 2024, at a CAGR of 5.84% during the forecast period.

There are three types of wet electrostatic precipitator, according to the different dust collectors: metal plate WESP, conductive FRP Plate WESP, flexible plate WESP.
Metal plate WESP uses flat plate construction as the anode plate, it spurted water to clean, and it is now the dominant player in the market. It has a mature technology. The dust collector material usually is stainless steel 316L. Metal Plate WESP usually has a horizontal structure, the flue gas flat into and flat out. Now many mainly manufacturer use this metal plate WESP as their main product
Conductive FRP plate WESP uses conductive FRP as the anode plate. It has a plate with tubular structure; the shape of section is usually regular hexagon, it adopts regular intermittent water spraying cleaning method, Conductive FRP plate WESP usually has a vertical structure.
Flexible plate WESP uses organic synthetic fiber as the anode plate. Its wetted fiber plate has conductivity so it can collect droplets in the flue gas. It has two ways to clean the dust: by surface water film and by upper nozzle. Flexible plate WESP usually has a vertical structure
There are three steps to work for Wet Electrostatic Precipitator:
1. Charging – gas ions created by corona from discharge electrode charge flue gas particles.
2. Collection- the charged particles/mists are attracted to the oppositely charged collection electrode surface.
3. Cleaning – the collected particles/mists are washed away by water, preventing build-up on the collection surface.

Key players in global wet electrostatic precipitator market include: The Babcock & Wilcox, Mitsubishi Hitachi Power Systems, GE Steam Power, Envitech, Bionomic Industries, Airpol, Trion, PPC Air Pollution Control Systems, Sumitomo, Clyde Bergemann, Scheuch, Feida Environmental.