The effectiveness of polymeric flocculant addition and hydrodynamics on increasing the critical permeation flux, J(crit), during crossflow microfiltration of bentonite suspensions using a tubular ceramic membrane module was investigated. The investigation determined the effects of flocculant concentration on J(crit) at various crossflow velocities. The best filtration performance (highest J(crit)) was obtained at a flocculant dose of 500 mg kg(-1) (mg of flocculant per kg of solids) and at a crossflow velocity of 1.71m s(-1). Particle size has been used as a parameter to fit the shear-induced hydrodynamic diffusion model to the experimental filtration data.