Classification of Membrane Gas Filters and Their Performance Evaluation

Abstract

Membrane filters are recently used as an in-line filter to eliminate particulate matters from process gases because they have a high collection efficiency compared to HEPA filters and shedding of fibers does not occur. The membrane filters are complicated and versatile in structure, making it difficult to predict their collection efficiencies. In the present work, membrane filters were classified into five groups according to the structure, and the collection performances of the filters in each group were evaluated from both collection efficiency and pressure drop by using filter figure of merit. Further, in predicting collection efficiency of membrane filters with fiber-like structure, the applicability of the conventional filtration theory for fibrous filters was tested.