Investigation of Filter Cake Stability using Numerical Simulation Technique

Filter cake stability was described by a particle dynamics model. The significance of Brownian motion relative to an absorption flow on the deterioration of the filter cake was of particular interest in the study. Brownian motion was modeled by applying a randomly directed force to each particle at each time step. Monodisperse and polydisperse systems of electrostatically stabilized rigid spheres were examined. The results characterize the microscopic structures, density profiles and thicknesses of filter cakes. The disruption of a dense filter cake is caused by diffusion if the dewatering rate or particle size is small or temperature is high. For typical dewatering rates, only particles less than 0.2 { extmu}m are able to diffuse a significant amount to cause a gradient in particle concentration over a filter cake.