Effect of Parameters of Filtration on Dust Cleaning Fabrics

摘要

The report summarizes 4 years of laboratory and large-scale tests on the dust filtration process and the basic filtration parameters that determine performance. Physical parameters describing fabric and dust cake structure were defined and three basic dust filtration mechanisms were considered: selective precipitation, inertial sedimentation, and diffusion. From test results of two Polish polyester fabrics filtering separated fly ash, three-dimensional probabilistic models of dust collection efficiency and filtration resistance were introduced. Also developed was a general filtration model, based on random field theory, that included full mathematical augmentation. The effect of electrostatic phenomena on dust filtration was examined in an attempt to define its influence. Study conclusions included: (1) air flow through a clean fabric and the dust filtration process are normal stochastic processes; (2) dust filtration is a specific dry filtration process, differing from the air filtration process or the high-efficiency air filtration process; (3) dust collection efficiency during the dust filtration process depends on three basic filtration mechanisms related to the aerosol particle size distribution; and (4) woven filtration materials are heterogenous and anistropic media characterized by periodic structure that, at high face velocity values exhibit transition region flow of Kl.