Combined depth and cake filtration model coupled with flow simulation for flat and pleated filters

Filtration processes characterized by initial depth filtration, followed by a stage during which the cake acts as both a depth and surface filtering medium are studied. Such phenomena can occur especially for polydisperse dust. Based on one-dimensional depth filtration modeling, a combined depth and cake filtration model is formulated and coupled with the fluid flow. The evolution of flow resistivity and filtration efficiencies is studied in the case of relatively dilute suspensions and constant flow rates. Numerical simulations of single-pass experiments are performed for both flat and pleated filter media. The model presented here is able to predict a nonlinear pressure drop for incompressible filter cakes due to the reduction of pore volume by particle deposition in the cake region.