Treatment of Low Pressure Type Reverse Osmosis Membranes for Recovery of Plating Rinse Waste Water for Recycling

摘要

For the purpose of recyclin system of waste water from plating rinse,process we investigated the treatment by low pressure type reverse osmosis membranes (effective membrane area:1.7m~2).In the case of 50% recoveryof permeate water fromfeed,the membrane showed the stable performance,but in the case of 80% recovery,the membrane performance decreased gradually with generating the scale ofsiica compounds on the membrna surface.In ordeer to recover the membrane performance,we investigated to wash the membrane surface using ethylene-diamine-tetraacetic acid,tetrasodium salt hydrate (EDTA-4Na)aqueous solutions.The membranes treated with these solutions showed the same membrane perofrmance as the initial ones.In a pilot plant (effective membrane area:36m~2),the membrane showed the stable performance by the eery 200 hours of washing treatment using EDTA-4Na aqueous solution.