Patent ID: 8685252
Filing Date: 2014-04-01
Classification: B01D,C02F

Abstract:
1. A method of treating a liquid containing membrane foulants, the method comprising: adding antifouling particles to the liquid, the antifouling particles having a specific surface area of 10 m supplying the liquid to a pressure vessel, the pressure vessel having an inlet, a permeate outlet, and a spiral-wound reverse osmosis or nanofiltration membrane element disposed within the pressure vessel, the membrane element having one or more membrane sheets spaced apart at a spacing of from about 1 mm to about 8 mm; applying a pressure differential across the spiral-wound reverse osmosis or nanofiltration membrane element so as to drive a reverse osmosis or nanofiltration process across the membrane element; circulating the liquid and the antifouling particles past the spiral-wound reverse osmosis or nanofiltration membrane element in the pressure vessel, wherein the antifouling particles coat membrane surfaces of the spiral-wound reverse osmosis or nanofiltration membrane element to form a protective layer over the membrane surfaces that attracts and holds membrane foulants while allowing passage of permeate through the spiral-wound reverse osmosis or nanofiltration membrane element; and collecting the permeate from the permeate outlet.