Abstract

Utylization of ionic wind and suppression of dust re-entrainment are important for performance of electrostatic precipitators (ESPs). Use of fibrous collection electrode is one of promising method. Ionic wind enhances dust migration towards collecting electrode, and fibers planted vertically on the collecting electrode decelerate ionic wind to prevent backward air flow that causes re-entrainment. In addition, gradient force at the fiber tip also works to prevent re-rentrainment. Other effective method, such as Ac energization and wet ESPs have also been used for cleaning suspended particles in tunnel, or for achieving very high efficiency together with simultaneous removal of gaseous pollutants. For indoor air, suppression of ozone production associated with corona discharge can be made using silver or titanium for positive discharge electrode. These recent deveiopments will expand application field of ESPs.