Chemical cleaning of ultrafiltration membranes in the milk industry

Ultrafiltration (UF) is one of the membrane processes has the most applications in dairy industries such as milk dehydration and whey concentration. Fouling of UF membranes in the milk industry is mostly due to precipitation of microorganisms, proteins, fats and minerals on the membrane surfaces. Thus, chemical cleaning of the membranes is essential. Results from investigations on a polysulfone UF membrane fouled by precipitation of milk components are presented. The effect of different cleaning agents on recovery of the fouled membrane was studied. Results showed that a combination of sodium dodecyl sulfate, EDTA and sodium hydroxide could be used as a cleaning material to reach an optimum recovery of the membrane used for milk dehydration. It seems that the results obtained on an experimental scale can be applied to an industrial scale, and the method is able to overcome fouling on any scale.