Investigation of the effect of fluid elasticity on a cake filtration process

Abstract

AbstractThe paper is concerned with the constant pressure cake filtration of suspensions in viscoelastic fluids. The filtration equations, based on the capillary hybrid model for power law fluid flow, were used for the description of this type of filtration. Filtration experiments with suspensions of nearly spherical polystyrene particles Krasten in viscoelastic aqueous solutions of polyacrylamide Praestol were carried out at constant pressure in a laboratory cylindrical filtration unit. The fluid rheological properties were measured on a rotational rheometer Haake RheoStress 150. Elastic effects manifested themselves predominantly at the early period of the filtration due to higher filtration velocity which resulted in an evidently increased filtration resistance. Analysing the experimental data, procedures for the evaluation of the effective specific filter cake resistance γ ef, filter screen resistance R fs, and the elongation flow coefficient E have been proposed. The filtration process predicted using the proposed filtration equation agrees very well with that determined experimentally.