In this study, the internal phenomena that occur during cake filtration, expression and hindered sedimentation were calculated and experimented using the ‘unified theory on solid-liquid separation’ with new boundary conditions. The expression procedure, the variation of pressure distribution in a compressible and incompressible cake were calculated. The procedure of hindered sedimentation was calculated with the new boundary conditions from ‘unified theory on solidliquid separation’ and experiments against various concentration.

The aim of this study is to measure the exact average specific cake resistance in cake filtration. Using the new experimental method “filtration-permeation,” the average specific resistances were measured for various conditions as follows. First, the experiment with changing pre-sedimentation time and the filtration of sediment were conducted to determine the influence of sedimentation on the average specific resistance. There was a wide difference between the values of αav with various sedimentation times. Regarding the variation in the pre-sedimentation time, there was maximum 2.9x difference between the measured values of the average specific resistances for the filtration of calcium carbonate suspension. The “filtration-permeation” of bentonite floc and that of biological flow were also performed to establish a method for obtaining the average specific resistance of flocs.