Nonuniform deposition of particles inside the pores of a semipermeable membrane

Macroscopic equations of the theory of filtration through granular beds are used to consider the spatial nonuniformity of particle deposition on pore walls during the standard blocking of the pores of ultrafiltration (UF) and microfiltration (MF) membranes. It is shown that the thickness of the layer of particles deposited inside the pore is characterized by a high degree of nonuniformity, which considerably affects the values of membrane permeate flux and selectivity. The effect of pore diameter, pore length, transmembrane pressure, and the coefficient of particle deposition onto the inner pore surface on the performance of standard blocking is studied. A dimensionless number representing the combination of the above parameters is proposed. The number can be used for optimizing the choice of membranes and process parameters for the UF and MF processes using standard blocking.