Effect of humidity and particle hygroscopicity on the mass loading capacity of high efficiency particulate air (HEPA) filters

Journal Article · Thu Jul 01 00:00:00 EDT 1993 · Aerosol Science and Technology; (United States)

DOI:https://doi.org/10.1080/02786829308959624· OSTI ID:5685673

Gupta, A; Biswas, P ^[1]; Monson, P R ^[2]; Novick, V J ^[3]

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1. Univ. of Cincinnati, OH (United States)
2. Westinghouse Savannah River Company, Aiken, SC (United States)
3. Argonne National Lab., IL (United States)

The effect of humidity, particle hygroscopicity, and size on the mass loading capacity of glass fiber high efficiency particulate air filters was studied. Above the deliquescent point, the pressure drop across the filter increased nonlinearly with areal loading density (mass collected/filtration area) of a NaCl aerosol, thus significantly reducing the mass loading capacity of the filter compared to dry hygroscopic or nonhygroscopic particle mass loadings. The specific cake resistance K[sub 2] was computed for different test conditions and used as a measure of the mass loading capacity. K[sub 2] was found to decrease with increasing humidity for nonhygroscopic aluminum oxide particles and for hygroscopic NaCl particles (at humidities below the deliquescent point). It is postulated that an increase in humidity leads to the formation of a more open particulate cake which lowers the pressure drop for a given mass loading. A formula for predicting K[sub 2] for lognormally distributed aerosols (parameters obtained from impactor data) was derived. The resistance factor, R, calculated using this formula was compared to the theoretical R calculated using the Rudnick-Happel expression. For the nonhygroscopic aluminum oxide, the agreement was good but for the hygroscopic sodium chloride, due to large variation in the cake porosity estimates, the agreement was poor. 17 refs., 6 figs., 3 tabs.

• DOE Contract Number: W-31109-ENG-38; AC09-89SR18035
• OSTI ID: 5685673
• Journal Information: Aerosol Science and Technology; (United States), Vol. 19:1; ISSN 0278-6826
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
AIR FILTERS
MATHEMATICAL MODELS
PRESSURE DROP
WATER COOLED REACTORS
ACCIDENTS
AEROSOLS
ALUMINIUM OXIDES
DUSTS
EXPERIMENTAL DATA
FIBERGLASS
HUMIDITY
HYGROSCOPICITY
SODIUM CHLORIDES
ALKALI METAL COMPOUNDS
ALUMINIUM COMPOUNDS
CHALCOGENIDES
CHLORIDES
CHLORINE COMPOUNDS
COLLOIDS
COMPOSITE MATERIALS
DATA
DISPERSIONS
EQUIPMENT
FILTERS
HALIDES
HALOGEN COMPOUNDS
INFORMATION
MATERIALS
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
POLLUTION CONTROL EQUIPMENT
REACTORS
SODIUM COMPOUNDS
SOLS
220504* - Nuclear Reactor Technology- Environmental Aspects- Design Basis & Hypothetical Accidents- (1992-)
210100 - Power Reactors
Nonbreeding
Light-Water Moderated
Boiling Water Cooled