Development and evaluation of multilayer air filter media

Three types of multilayer air filter media were developed and evaluated. Tw o other existing filters were also used for comparison of filter performanc e. The pressure drop, the collection efficiency, and the dust-holding capac ity of the tested filters were measured, and the internal structure of the filter media was analyzed by using a scanning electron microscope. The mult ilayer filters tested in this study are composed of pre-surface layer, surf ace layer, and substrate layer. Among those layers, the surface layer is ma inly responsible for particle collection. As a test result, it was found th at the thickness of a surface layer has the greatest effect on filtration p erformance of a multilayer air filter. Additionally, filtration velocity an d electrostatic forces should be considered together as important parameter s for multilayer air filter design.