Aerosol penetration properties of an electret filter with submicron aerosols with various operating factors

This study was undertaken to determine the effects of using an electret filter on aerosol penetration. Various factors, including particle size (0.05 to 0.5 μ m), aerosol charge state (neutral and single charge), face velocity (0.1, 0.3, 0.5 and 1.0 m/s), and relative humidity (RH 30% and RH 70%), were examined to assess their effects on aerosol collection characteristics. The results presented here demonstrate that the electric fields of the electret and discharged filter were −1.53 × 104 and −1.3 × 102 (V/m). The penetration through the electret filter with singly charged aerosol and neutral aerosol ranged from 0.4% to 13% and 14% to 29%, respectively. According to these results, the coulombic capture force was dominant for the smaller aerosol and the dielectrophoretic capture mechanism was considered important for the larger aerosol. The level of penetration through the electret filter increased with increasing face velocity and relative humidity. The temperature did not affect the penetration through the electret. Furthermore, from the regression analysis conducted during the operating conditions of this work, the aerosol charge was shown to exert the greatest influence on aerosol penetration.

[1]  Shinhao Yang,et al.  Electrostatic Enhancement of Collection Efficiency of the Fibrous Filter Pretreated with Ionic Surfactants , 2005, Journal of the Air & Waste Management Association.

[2]  Gwi-Nam Bae,et al.  Effect of particle loading on the collection performance of an electret cabin air filter for submicron aerosols , 2003 .

[3]  E. Motyl,et al.  Electret properties of polypropylene fabrics , 2001 .

[4]  Leonard W. Barrett,et al.  Aerosol Loading Performance of Electret Filter Media , 1998 .

[5]  C C Chen,et al.  The effects of particle charge on the performance of a filtering facepiece. , 1998, American Industrial Hygiene Association journal.

[6]  D. C. Walsh,et al.  Clogging of an electrically active fibrous filter material: Experimental results and two-dimensional simulations , 1997 .

[7]  A. Ginestet,et al.  The fractional efficiency of air filters used in general ventilation , 1997 .

[8]  L. Wallace,et al.  Indoor particles: a review. , 1996, Journal of the Air & Waste Management Association.

[9]  Tadao Nakamura,et al.  Charge stability of TPX film electrets , 1995 .

[10]  Kimmo Heinonen,et al.  Reliability of electret filters , 1994 .

[11]  G. Stevens,et al.  "Worst case" aerosol testing parameters: II. Efficiency dependence of commercial respirator filters on humidity pretreatment. , 1989, American Industrial Hygiene Association journal.

[12]  R. Fjeld,et al.  The effect of particle charge on penetration in an electret filter , 1988 .

[13]  Chikao Kanaoka,et al.  Coulombic deposition mechanism in electret filters , 1987 .

[14]  D. C. Walsh,et al.  Parameters Affecting the Loading Behavior and Degradation of Electrically Active Filter Materials , 1998 .

[15]  Benjamin Y. H. Liu,et al.  Experimental Study of Electrostatic Capture Mechanisms in Commercial Electret Filters , 1998 .

[16]  R. Brown,et al.  The effect of aerosol charge and filter charge on the filtration of submicrometre aerosols , 1990 .

[17]  Y. Otani,et al.  Effect of Charging State of Particles on Electret Filtration , 1987 .

[18]  Heinz Fissan,et al.  Enhancement of particle deposition in filters due to electrostatic effects , 1987 .

[19]  Friedrich Löffler,et al.  The collection performance of electret filters in the particle size range 10 nm-10 μm , 1986 .

[20]  H. Fissan,et al.  Deposition of submicron particles on electrically charged fibers , 1986 .

[21]  M. Ackley Degradation of electrostatic filters at elevated temperature and humidity , 1985 .

[22]  R. Brown Capture of dust particles in filters by linedipole charged fibres , 1981 .

[23]  G. Watt,et al.  Air filtration. , 1980, Hospital engineering.