Constant pressure filtration of mono-dispersed deformable particle slurry

Constant pressure filtration experiments of Ca-alginate gel particle, Sacch aromyces cerevisiae, and polymethyl methacrylate (PMMA) were conducted to s tudy the local properties of cake layer formation by deformable particles. Effects of particle deformation due to frictional drag and cake mass on cak e compression and contact area among particles were examined. The factors t hat lead to the increase in filtration resistance were discussed. The dynam ic analysis proposed by Lu and Hwang in 1993 was modified to analyze format ion and compression of cake during cake filtration of deformable particle s lurry. A thin skin layer of low porosity and high resistance was formed nex t to the filter medium due to severe deformation, caused by frictional drag , of the first layer. The results of this study clearly indicate that negle cting the area-contact effect among particles will lead to an overestimate of cake porosity, and neglecting the transient effect of cake compression d uring gel layer formation will result in an underestimate of cake porosity. The characteristic values of filter cake obtained from dynamic analysis ca n be used to predict the performance of the filtration of slurries containi ng deformable particles.