AAAR 31st Annual Conference
October 8-12, 2012
Hyatt Regency Minneapolis
Minneapolis, Minnesota, USA
Abstract View
Comparison of Charging States between Electrospun and Electret Meltblown Filter Media through Filtration Test for Submicrometer Aerosol
Hyun-Seol Park, WEONGYU SHIN, Korea Institute of Energy Research
Abstract Number: 417 Working Group: Control Technology
Abstract Electrically charged air filters have a great advantage because electrostatic forces acting between filter fibers and oncoming particles enhance the filtration efficiency without increasing air resistance through the filter. In this study, we have compared the electric charging state of electrospun filter media and corona charged meltblown filter media. Electrospun filter media were prepared by a lab scale electrospinning machine, and the meltblown filter was commercial one, which was electrically charged by a corona filter charging methods. To verify the effect of filter charge, the collection efficiency was measured for test filters before and after discharging. To remove the filter charge, filter samples were discharged via isopropanol dipping method. In detail, all tested filter media were completely immersed in isopropanol bath for 10 min, and dried for 60 min at 70C. The collection efficiencies for monodisperse particles ranging 30 ~ 250 nm were compared. When a filter media get charged, collection efficiency of the filter should be distinguished from that of uncharged one. In this study, the meltblown filter media showed a big difference incollection efficiency between charged and discharged filters. In some cases, the collection efficiency decreased from 99% to 40%. On the other hand, electrospun filters showed only little difference. As a result of direct measurement of surface potential of test filters, the electric charge of electrospun filter was drastically decayed and finally reached to zero in a few seconds, for some cases in hours, while the corona charged meltblown filter media showed very slight loss of charge for over 20 hours. Generally it was known that the electrospun fiber has some charges during spinning process. Even though limited to this study, however, it can be concluded that the electrospun filters have no effective electrical charges.
This research was supported by the Converging Research Center Program through the National Research Foundation of Korea(NRF) funded by the Ministry of Education, Science and Technology.