Front End to Backpipe: Membrane Technology in the Starch Processing Industry

Abstract

The starch processing industry is characterized by streams that vary in diversity and complexity and that require extensive processing to achieve high end product quality. Water removal and product separations are two fundamental processing steps that impact product quality and processing economics. Many uses have been found for membrane technology in the starch processing industry; these include pretreatment of fresh water, recovery of solids and wastewater treatment. In many cases, membrane applications have increased quality of products, decreased energy costs and reduced disposal issues relating to waste treatment. Membranes can be used to filter many types of fluids in potato, wheat and corn starch isolation processes with varying degrees of success. Robust membrane materials have been developed with unique processing capabilities suited for the needs of the starch processing industry. Membranes have been used commercially to increase product quality while reducing costs, such as in syrup and sweetener clarification. Membrane technology has shown promise for reducing evaporation costs, improving product recovery and removing solids prior to wastewater treatment. In many applications, the cost of dewatering using membranes was a fraction of the cost of traditional methods. Membranes can be used to recover proteins from dilute process streams, but more work is needed regarding changes in nutrient quality when membranes are used in place of conventional separation technologies such as centrifugation, vacuum belt filtration and evaporation. There is need for detailed discussion of analyses regarding economics of long term operation and maintenance of membranes as part of a processing system.