Membrane-based no-waste extract decolorization process

Molasses desugarization using simulated moving bed chromatography has been widely adopted within the beet sugar industry, particularly in the USA. Processing of the high-purity extract fraction from this operation can be integrated into the factory in several ways. However, since the extract is typically higher in color and purity than thick juice, extract crystallization using the standard three-stage crystallization scheme can be challenging. Recently, this problem was solved when Amalgamated Research developed and patented a “no-waste” decolorization process that uses membrane nanofiltration to recover inorganic salts from the separator raffinate stream and uses these to regenerate an ion exchange resin in extract decolorization service. After regeneration, the spent regenerant is recombined with the raffinate stream without affecting its value as a co-product. Extensive pilot testing with materials from several facilities has demonstrated that high resin color loadings can be achieved while providing extract decolorization of about 70%. This promising technology can improve overall sugar-end performance by reducing sugar recycling, thereby increasing overall sucrose extraction.