ULTRAFILTRATION OF SKIM MILK IN FLAT-PLATE AND SPIRAL-WOUND MODULES

The objective of this work was to develop and test methods of predicti ng permeate flux in a spiral-wound ultrafiltration system from experim ents run on a small flat membrane module. Two models were based on a t raditional mass transfer (Sherwood) correlation and two on resistance theory. Three of the pressure on the permeate flux. Experimentally mea sured permeate fluxes from skim milk in the spiral-wound unit were com pared to model predictions from four correlations fitted to experiment al data from the small-scale, flat-membrane system. While all correlat ions under-predicted flux at low cross-flow velocity and over-predicte d at high velocity, the ability of each correlation to predict an aver age flux was very good, indicating that data from flat-membrane be use d, under carefully controlled conditions, to predict a spiral-wound sy stem. (C) 1997 Elsevier Science Limited. All rights reserved.