Filtration of suspensions with forming of an elasto-plastic cake

Abstract

In this paper, filtration equations of suspensions through porous filters with forming a cake layer on the inlet surface of the medium, that can exhibit elastic-plastic properties, are derived. The filtration equations are numerically solved both at the loading and unloading regimes. Distributions of the cake concentration and its permeability are determined at pressure increasing and decreasing regimes that show their irreversible behaviour. According to irreversibility parameters residual effects can be different. At reloading of the system after some rest time the growth of the cake proceeds, but with another characteristics. The transit of filtration characteristics to former conditions, corresponding to the previous loading, occurs gradually, from point to point of the cake, but enough quickly. As a result, the elastic-plastic behaviour of the cake essentially changes both the growth dynamics and filtration characteristics.