Cake structure in dead-end membrane filtration: Monte Carlo simulations

A statistical mechanical approach for predicting the long-term gradual flux decline due to colloid-cake formation in dead-end membrane filtration is presented. Monte Carlo simulations of cake layers composed of interacting colloidal particles are performed to predict volume fractions and corresponding radial distribution functions. The total osmotic pressure in the cake layer is extracted from interparticle interactions and the radial distribution function. The extracted osmotic pressure predictions are in good agreement with applied pressure, verifying the accuracy of the simulation method. The simulation method is then used to investigate the effect of particle size, ionic strength, zeta potential, and applied pressure on the cake structure, which is represented by the volume fraction and the radial distribution function. Finally, the influence of these effects on permeate flux decline during the dead-end membrane filtration of interacting colloidal particles is predicted and qualitatively compared to previously published experimental data.