Finally, the principal
components in an electrostatic precipitator are a discharge plate and a collecting surface.
The separation is effected by charging the particles with a high voltage and allowing the
charged particles to be attracted to the oppositely charged collection plates.
T o obtain the greatest efficiency in particulate removal, additional attention must
be given to particle diameter and air velocity. The particle size determines the separat-
ing force required, while the effectiveness of the control equipment is related to the
stream velocity. Generally, the greater the relative velocity between the airstrearn and
the collision obstacle for the particulates, the more effective the separating mechanism.
The electrostatic precipitator is an exception to this generality, since here the particle
diameter influences the migratory velocity and the power required to maintain the elec-
trical field that influences the equipment performance. Figure 2-2 illustrates the char-
acteristics of various pollution particulates and the range of application for several
control devices as related to particle size.
discharge