An experimental and theoretical study on the initial period of cake filtration

Experimental measurements were made of the average specific cake resistance during the initial period of cake filtration, and the theoretical calculat ions about the period were also performed. The "filtration-permeation metho d" in the filtration cell of small area was used to measure the flow rate d uring the initial period of filtration, which is essentially characterized by the large flux due to fast now rate and the rapid change of flow rate wi thin a relatively short time interval. The measured average specific cake r esistances of thin cakes which represent the cakes of initial period had ve ry large values compared to the overall average specific cake resistance. T his experimental result was contrary to the conventional theory about the i nitial period. Applying the 'unified theory on solid-liquid separation" to the initial period, the average specific cake resistances at the initial pe riod can have the large values-more than two times greater than that of the overall value.