For studying the correlation between filtration and permeation, the newly derived rigorous analytical method which i ncludes the expressions for the flow rate distribution
qz/
q1, through the entire cake and for the true average specific resistance ar was used. The predicted filtration characteristics are compared favorably with actual constant pressure filtration results of dense slurries of various clays.
i) The value of correction factor
J, defined by Eq. 13 depends mainly on slurry concentration s but slightly on filtration pressure
p. The numerical values of
J drop into the neighborhood of 0.9 for dense slurries as shown in Fig. 4. As far as compressible thick slurries are concerned, it has become clear that the conventional theory should be modified.
ii) On both sides of theoretical analysis and experimental studies, it is clear that the average specific resistance of filter-cake should be a function of both
p and
s. The maximum specific resistance of a cake is supposed to be encountered at the washing stage of the cake.
iii) The ratio of wet cake mass to dry cake mass is also a function of both
p and
s. The ratio depends mainly on
p and slightly on
S.
iv) The modern filtration theory is expected to be able to cover various practical aspects of filtration behaviors.
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