10th International Aerosol Conference September 2 - September 7, 2018 America's Center Convention Complex St. Louis, Missouri, USA
Abstract View
Comparison of Different Neutralizing Methods by IPA on Electret Filter Media
MIN TANG, Sheng-Chieh Chen, Drew Thompson, David Y. H. Pui, University of Minnesota
Abstract Number: 103 Working Group: Control and Mitigation
Abstract It has been broadly demonstrated that electrostatic charges added to polymer fibers by creating electrets will improve particle capture abilities without increasing the pressure drop. Filtration applications require knowledge of the minimum efficiency provided by a filter (worst-case performance). In existing test standards, e.g. EN 779 and ISO 16890, isopropanol (IPA, in liquid or vapor phase) is used to eliminate electrostatic effects from filter media. There is few report about whether IPA liquid and vapor can fully discharge the electret media. Currently, there is a huge controversy in fiber charge characterization techniques for electret media. This study developed a simple and reliable method to determine whether the filter media were fully discharged. The neutralization effect of IPA liquid and vapor discharging was compared. The results showed that IPA vapor treatment showed better neutralization effect than IPA liquid immersion, since IPA liquid treatment can induce undesirable charges on fiber surface. It was found that IPA vapor did not have the ability to discharge electret media. The discharging process was that IPA vapor condensed on the charged surface and remove the static charge. Proper design of IPA vapor chamber to allow vapor condensation on fiber surface is important to efficiently remove charges of electret media.