Utilization of a shear induced diffusion model to predict permeate flux in the crossflow ultrafiltration of macromolecules

In this paper a shear-induced diffusion model is used to predict permeate flux decline with time in the ultrafiltration of macromolecules. The results estimated by the model were compared with the experimental results obtained in a pilot plant. Tubular ZrO2–TiO2 ceramic membranes with a molecular weight cut-off of 15 kDa (Orelis, France) were used. The fouling experiments were performed with 5 g/L PEG (35000 Da molecular weight) aqueous solutions at different transmembrane pressures and crossflow velocities. Flux decline was predicted without the utilization of empirical parameters dependent on the operating conditions. Good predictions were obtained for all time scales in the case of low crossflow velocities. For high crossflow velocities, the results predicted by the model were good only for long time scales.