Polydispersity 조건에서 Crossflow 방식 정밀여과 공정의 케이크 형성 특성

Abstract

Cake formation at polydisperse condition has been studied experimentally and compared with that at monodisperse condition reported in previous researches. Kaolin and two kinds of CaCO₃ are used as particles and polysulfon hollow fiber microfilter is used as membrane for the experiment. This study evaluates the effects of particle size and shear rate which affect cake formation in crossflow microfiltration. EDSD (Effective Diameter for Shear-induced Diffusion) is used as a representative particle size for particles with various sizes. At polydisperse condition, the effect of shear rate on cake formation IS similar to those at monodisperse condition. Cake formation increases with the decrease of shear rate and the increase of feed concentration. But polydispersity makes the quantitative differences of the effects between monodisperse and polydisperse condition. Comparing all the effects of particle size and shear rate on cake formation, this study indicates that particle size is a crucial influential factor for cake formation at polydisperse condition and suggests that increasing particle size is the most efficient way to decrease cake formation.