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Gas Cleaning Methods for Ambient Air and Compressed Gases

  • Alvin Lieberman

Abstract

Cleaning air or compressed gases in cleanroom installations requires removal of particulate and/or gaseous contaminants. The technology used for cleaning gases for the cleanroom is derived from processes long used in industrial applications for dust and smoke removal. Removal of particles from gases in industrial applications may involve methods such as centrifugal cleaning, wet scrubbing, electrostatic precipitation, or filtration as used for fossil fuel power plant emission control. For cleanroom operations, filtration is essentially the only process by which particles are removed from both ambient air and from compressed gases; contaminant gases are removed either by dry bed adsorption or by wet scrubbing. Electrostatic precipitation is practically never used in cleanroom operation for control of ambient air cleanliness. The method is considered suspect because operators are concerned about possible particle emission from precipitator elements in the case of power failure. However, there is increasing interest in electrostatically augmented filtration. This process operates by improving particle deposition to the filter fibers. Even if a power failure occurs, the material already collected within the filter remains there. More details are given later.

Keywords

Filter Medium Work Area Filtration Efficiency Electrostatic Precipitation Face Velocity 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Van Nostrand Reinhold 1992

Authors and Affiliations

  • Alvin Lieberman

There are no affiliations available

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