Direct white sugar manufacture in the cane sugar industry via membrane filtration and continuous ion-exchange demineralization

摘要

The patented White Sugar Mill (WSM) technology is a result of a research and development joint-venture entered into by Tongaat-Hulett Sugar Limited and South African Bioproducts Limited in 1998. The WSM technology produces white sugar directly from raw cane juice, thereby eliminating the refining process, with all its associated costs; and it unlocks the value of the sugars currently found in molasses. Furthermore the technology enhances sugar recovery and allows a liquid fertilizer that is high in nitrogen and potassium to be produced. The technology applies a combination of membrane filtration, ion-exchange demineralization and ion-exchange decolorization, after conventional juice clarification to produce a high quality juice from which white sugar may be crystallized. The technology has been piloted successfully in both South Africa and Brazil over a number of years, and in 2005 the first production scale WSM plant was built and commissioned at Felixton Mill in South Africa. The WSM technology can either be applied to a greenfields application, or as is the case with Felixton, retrofitted to an existing factory.