Ultrafiltration of sugarcane juice with spiral wound modules: on-site pilot trials

This work investigates the performance of spiral wound membrane modules for the ultrafiltration (UF) of sugarcane juice. In on-site trials carried out in an Indian sugar mill, different modules with varying channel sizes empl oying 20kDa polyethersulphone and polysulphone membranes were evaluated. Tw o juice streams viz. raw juice and clarified juice were selected in the sug ar manufacturing process and the effect of such operating parameters as tra nsmembrane pressure, operating time and feed temperature on the permeate fl ux and quality were examined. It was observed that a narrow channel size re sulted in a higher flux with a corresponding lower membrane fouling. The fl ux could be further improved by increasing the operating temperature. With both the feed streams, the permeate was observed to be consistently superio r in terms of higher clarity, lower color and reduced calcium oxide content as compared to the clarified juice produced by the conventional double sul phitation process. (C) 2000 Elsevier Science B.V. All rights reserved.