Constant pressure filtration of power-law non-newtonian fluids.

Abstract

A filtration theory for the power-law non-Newtonian fluids is developed on the basis of the extended Rabinowitsch-Mooney equation, and several definitions of non-Newtonian filtration characteristics are defined. The equations presented in this paper may be considered as equations applicable both for non-Newtonian filtration and for conventional Newtonian filtration. Methods for evaluating the overall characteristics of non-Newtonian filtration are suggested by using the compression permeability data. In order to confirm the validity of the theory, constant pressure filtration experiments are carried out under various conditions of the flow behavior index N ranging from 0.404 to 0.504 and the filtration pressure p from 1000 to 3000 G/cm2, and it is shown that the methods presented in this paper are valid. It is also shown that the average specific filtration resistance varies considerably with change in the N-value of the power-law, and the cakes formed from non-Newtonian filtration of pseudo-plastic fluid are denser than those from usual Newtonian filtration.