Comparative study of different nanofiltration and reverse osmosis membranes for dairy effluent treatment by dead-end filtration

At the end of run (VRF 3) with an initial highly charged feed, COD of permeate was always far away the quality of water for human consumption (total organic carbon, TOC < 2 mg/L) but RO permeate can be released as waste. Water quality close to vapour condensates, issued from milk and whey drying steps, is needed for reuse in boiler feed; it should be likely reached with an RO + RO cascade and possibly with a single RO with a low charged feed.