Introduction

Clean Air System (E.P, Electrostatic Precipitator) is based on principle of electrostatic. E.P makes contaminated particles to be electrostatic materials and to be collected. Clean Air System is structured by Pre Filter, Cell and After Filter.
Cell is organized the Ionizer and the Collector. So what is called Two Stage charge. The function of Pre Filter filters large contaminated particles. At ionizer, it makes contaminated particles to ionize by corona discharge which is applied high voltage (DC 10 ㎸ ~ 12 ㎸), and then ionized particles is collected at collector.
High voltage (DC 5 ㎸ ~ 7 ㎸) is supplied to Collector which is plate collected at regular distance. more than 0.01 µm contaminated particle collected at Collector. At the same time, After Filter makes clean air coming out and prevents collected particle from coming out. Clean Air System has benefit to filter 0.01 µm particles. The ratio of efficiency is more than 97%.

Electrostatic precipitators have the following advantages

• They have high efficiencies (exceeds 97% in some Application)
• Fine dust particles are collected efficiently
• Can function at high temperatures (as high as 700 degree F-1300 degree F)
• Pressure and temperature changes are small
• Difficult material like acid and tars can be collected
• They withstand extremely corrosive material
• Low power requirement for cleaning
• Dry dust is collected making recovery of lost product easy
• Large flow rates are possible

The efficiency of electrostatic precipitators can be increased by:

• Larger collection surface areas and lower air flow rates give more time and
  area for dust particles to collect
• Increased speed of dust particles towards collection electrodes
• Factors That Affect Efficiency
  - Some factors that could affection efficiency of the electrostatic precipitator are as follows:
  .Other gases in the air stream could affect efficiency
  .Some dusts have high charge and greater forces may be required to attract them to the collection plates
  .Sulfur compounds in boiler gas increase collector efficiency
  .Pressure drop usually in the range of 2.0 to 0.5 inches
• In the Two Stage Precipitator grounded plates are placed about an inch apart with an intermediate plate that is also charged. With the two-stage system, instead of 4000-6000 DC supply, it has 10000-12000 Volt supply with immediately supply at 7500 volts. Dust load in this system is normally between 0.01 to 0.1 grains per 1000 cu.ft

CELL Dimension & Figure

Specification

• Input Voltage
  . Ionizer Voltage : DC 12KV Ω10%
  . Collector Voltage : DC 6KV Ω10%
• Shape of ionizer part : saw type

Efficiency of electrical precipitator