Innovative and sustainable concept of regeneration of decolorization ion exchange resins

摘要

Regeneration of resins used for decolorization of sugar solutions is done with concentrated salt solutions. Nanofiltra-tion membranes have been proven effective, in terms of industrial efficiency in decreasing salt consumption. More than 90% of the salt that is necessary for regeneration can be recycled through a combination of direct recycling of intermediate eluates, the separation of colored compounds by use of very selective nanofiltration membranes and a multiple-effect evaporation of salty permeates. The desalted color compound solution is sent to the molasses, limiting considerably the effluent to be treated. Starting from a liquor of 800 IU, the water requirement is limited to less than 100 L/t of sugar and the amount of wastewater can be reduced to less than 40 L/t of sugar.