EXPRESSION FOR CRITICAL SUSPENDED PARTICLE-SIZE IN GRANULAR MEDIA FILTRATION PROCESSES

The critical suspended particle size is defined as the suspended parti cle size with a minimum collector efficiency in a packed bed filter. I dentification of the critical size particles is important when a granu lar filtration process is designed for removal of a mixture of suspend ed particles with different particle sizes. This note intends to deriv e a simple expression from the filtration model of Rajagopalan and Tie n [Rajagopalan, R. and Tien, C. (1976) Trajectory analysis of deep-bed filtration with the sphere-in-a-cell porous media model. AIChE J. 2(3 ), 523-533.] for the critical particle size and to investigate the eff ects of temperature, suspended particle density, collector diameter an d approach velocity on the critical particle size and the correspondin g collector efficiency. (C) 1998 Elsevier Science Ltd. All rights rese rved.