SEGREGATION VELOCITY MODEL FOR FLUIDIZED SUSPENSION OF BINARY MIXTUREOF PARTICLES

A segregation velocity model is presented here to describe the segrega tion behaviour of the fluidized beds containing binary mixture of part icles differing both in their size as well as the density. Using the R ichardson-Zaki correlation, the model evaluates the segregation veloci ty of the larger particle species which is assumed to be present in th e pseudo fluid consisting of a homogeneous mixture of the liquid and t he smaller particle species. The present model is capable of correctly describing the particle motion responsible for the observed segregati on tendencies of the fluidized bed. Moreover, the model predictions of the zero segregation velocity compares very well with the experimenta l data of the layer inversion phenomenon reported in the literature. T he model tends to over-predict the inversion velocity for cases where the diameter ratios of the larger to the smaller particle species are less than 2. (C) 1998 Elsevier Science S.A. All rights reserved.