Electrostatic precipitation of fine particles with a bipolar pre-charger

A laboratory electrostatic precipitator (ESP) together with a bipolar pre-charger has been designed for studying charge-induced agglomeration and fine particle collection. In terms of particle numbers, the ESP collection efficiency drops to its minimum of near 90% for particles with diameters of near 0.2 μm and 3 μm. For other particles, its value is around 94%–95%. By using the bipolar pre-charger, the grade efficiency can be significantly increased for all particle sizes due to the charge-induced particle agglomeration. The grade collection efficiency rises to about 95%–98% for all size particles.