Rinsing Behavior of Deposited Layers Formed on Membranes in Ultrafiltration

Abstract

ABSTRACT Skim milk and aqueous milk protein suspensions were ultrafiltered in a tubular module under controlled conditions (temperature, pressure, flow rate) and were subsequently rinsed with water also under controlled conditions. The effect of rinsing on the deposited layer was followed by observing the flux with time. Ultrafiltration and rinsing should be carried out at high flow rates and at low pressures. Increasing the pressure led to an undesirable increase in the compactness of the deposit. Theoretical considerations of the mechanism of transport in and at the deposited layer made it possible to obtain data on the thickness of the deposits, on mass transfer coefficients and velocity profiles within deposits. The experimental rinsing curves could be well explained by the calculated results. The results should help to optimize the performance and cleaning of UF modules.