Demineralization of dairy streams and dairy mineral recovery using nanofiltration

Abstract

Nanofiltration is an effective technique for the concentration of lactose and for the reduction of salt in a variety of dairy streams. It is possible to recover important dairy minerals directly from the NF retentate for sale as dietary supplements. The membranes used commercially for nanofiltration are usually spiral wound polyamide membranes. The driving force for the flow of water across a nanofiltration membrane is predominantly the pressure difference between the feed and permeate sides. Concentration polarization in NF arises when the mass transfer resistance within the boundary layer of fluid above the membrane itself becomes significant. An understanding of the NF operation in dairy ..