Transport through composite membranes, part 2: Impacts of roughness on permeability and fouling

► Rough coatings have high flux through thin sections; thick features reduce flux. ► Surface roughness may create inherently uneven permeate flux. ► Interaction of roughness and support affects permeability and flux distribution. ► Flux distribution is dampened by a support with water-permeable solid phase. ► Flux distribution may explain high fouling propensity of polyamide membranes.