Electric Air Cleaner Filter Operation
In figure 1,below, a fan draws dust, smoke and other particulate into and through the electronic air cleaner. Larger particles are trapped by a Pre-filter Screen / Filter while smaller particles pass through into the Charged Section, where the particles are positively charged by a series of large diameter wires often made of tungsten.
The charged particles are then drawn into the Collection Section which is composed of a series of positive charged plates which propel the positively charged particles into a series of negatively charged plates, which attract and "hold" the particles.
Collected pollutants which are collected onto the negatively charged plates are removed at cleaning. Often, cleaned air is then circulated through a Charcoal Filter where moisture / odors are absorbed.
Reference: ASHRAE Handbook of Fundamentals, 1985; ASRAE Guide and Data Book application, 1987. Natural and Mechanical Ventilation, 1981
Figure 1