Membrane Filtration of Wheat Starch Solutions Using Tubular Ceramic Membranes

Abstract

Processing wheat flour into starch and gluten products is both water and energy intensive using current fractionation processes involving centrifuges and hydrocyclones. Resultant waste streams, known as starch tailings or starch milk, contain smaller starch granules, damaged starch, water unextractable non-starch polysaccharides, ash and low levels of proteins. This research involved the microfiltration of such a stream using tubular ceramic membranes (0.5, 0.35 and 0.2 um nominal pore size) for laboratory experiments with controlled operating conditions. It is envisaged that microfiltration would reduce the amount of residual solids in the final waste stream thus reducing costs associated with treatment options prior to discharge. Potentially the technology provides opportunities to extract water for reuse rather than discharging to sewer.