Dust Collector - Electrostatic Precipitators (ESP)

Electrostatic Precipitators (ESP)

Electrostatic precipitators use electrostatic forces to separate dust particles from exhaust gases. A number of high-voltage, direct-current discharge electrodes are placed between grounded collecting electrodes. The contaminated gases flow through the passage formed by the discharge and collecting electrodes. Electrostatic precipitators operate on the same principle as home "Ionic" air purifiers.

The airborne particles receive a negative charge as they pass through the ionized field between the electrodes. These charged particles are then attracted to a grounded or positively charged electrode and adhere to it.

The collected material on the electrodes is removed by rapping or vibrating the collecting electrodes either continuously or at a predetermined interval. Cleaning a precipitator can usually be done without interrupting the airflow.

The four main components of all electrostatic precipitators are-

• Power supply unit, to provide high-voltage DC power
• Ionizing section, to impart a charge to particulates in the gas stream
• A means of removing the collected particulates
• A housing to enclose the precipitator zone

The following factors affect the efficiency of electrostatic precipitators:

• Larger collection-surface areas and lower gas-flow rates increase efficiency because of the increased time available for electrical activity to treat the dust particles.
• An increase in the dust-particle migration velocity to the collecting electrodes increases efficiency. The migration velocity can be increased by

• • Decreasing the gas viscosity
  • Increasing the gas temperature
  • Increasing the voltage field