Particle collection of medium performance air filters consisting of binaryfibers under dust loaded conditions

Evolutions of collection efficiency and pressure drop of an air filter with dust load vary with the filter structure, such as mean fiber size, fiber s ize distribution, packing density, as well as the captured particle size an d filtration velocity. In the present work, time change in collection perfo rmance of medium performance air filters composing of binary fibers is stud ied in order to clarify the effect of fiber size distribution on the collec tion performance. As a result, it was found that, during the period of dept h filtration, the time change in collection performance of binary filters c an be predicted by assigning unique fractional collection efficiency raisin g factors, overall collection efficiency raising factors and pressure drop raising factors of individual fibers, suggesting that there are no interact ions between fibers with different sizes. This study confirms that mixing f ibers with various diameters is one of the effective means to adjust the ti me change in collection efficiency as well as initial collection performanc e. (C) 2000 Elsevier Science B.V. Ail rights reserved.