Principles of Wet Electrostatic Precipitator (WESP) Technology:

Electrostatic precipitation is made possible by the corona discharge. Through an effect known as the avalanche process, the corona discharge provides a simple and stable means of generating the ions to electrically charge and collect suspended air particles. Once charged, the particles are driven to the ground surface. The particles are then rinsed from the vertical collection surface with an irrigating liquid to the bottom sump where they are collected and discharged from the system.

In contrast to the up-flow system, the down-flow WESP system offers:

A higher secondary voltage that results in less collection area and fewer tubes and electrodes.
Gravity provides the driving force for self-cleaning of the tubes and minimizes or eliminates downtime caused by the build up of solids on the collection surface.
The flow of water required to clean the internal parts of the system is minimized. No external expensive heat exchangers or cooling systems are required to produce the self-irrigating feature