Ultrafiltration of Skimmilk in Hollow Fibers

Flux in hollow fiber ultrafiltration of skimmilk was modelled over the entire pressure‐flux region using the resistance approach. The Hagen‐Poiseuille model was adequate to describe water flux data: effect of temperature could be largely accounted for by viscosity of permeate. To describe skimmilk data, the model was modified to include a term due to resistance of the polarized layer (R P ) and R F , a resistance due to fouling by specific membrane‐solute interactions. R F was relatively independent of operating parameters, but R p was a function of velocity and feed concentration at a particular temperature. Under typical conditions of hollow fiber ultrafiltration of skimmilk, the membrane and fouling layer appeared to contribute little resistance to flux compared to resistance of the polarized layer.