Demineralization of sugar cane juice by electrodialysis

The demineralization of sugarcane juice was investigated in a two-phase project extending over two crushing seasons. In the first phase a bench scale electrodialysis unit, 100 cm x 50 cm in size, comprising 100 cell pairs of membranes was made and installed at M/s, Ponni Sugars and Chemicals Ltd., Erode, India. The clarified sugar cane juice was cooled to 45 - 50 degrees C, passed through filters and then through an electrodialysis (ED) stack to remove the inorganics. In a single pass operation, a 50 - 70% reduction in salt was achieved, with a rise in purity in the cane juice of around 40 degrees. In the second phase, three stacks of the above dimensions were used to allow juice flows of about 1200 - 1500/l per hour. The treated juice was concentrated and sent to a crystallizer according to standard procedures. The crystals obtained in the first strike had uniform size and the molasses obtained was brown in colour and palatable.