Desalting of RO Waste and Drainage Water by Direct Contact Membrane Distillation

Abstract

Direct contact membrane distillation is an effective method for production of fresh water from saline water. In this study two samples were used as feed solutions; the first one was RO waste from Al-Hilla Coca-Cola Factory (TDS= 2382 mg/l) and the other was Haji Ali drainage water (TDS= 4127 mg/l). Polytetrafluoroethylene (PTFE) hydrophobic membrane supported with polypropylene (PP) was used as flat sheet form with plate and frame cell. Results proved that membrane distillation is an effective technique to produce fresh water with high quality from brine with low salinity content. With membrane area of 8x8 cm2, the volume of treated water decreased from 34.97 ml at first half hour to 33.02 ml after 180 min of an experiment for first feed type and from 36.92 ml to 33.84 ml for the second feed type due to the fouling accumulated on the membrane surface. The temperature on both sides of the membrane surface and TDS of permeate was measured every 30 min of experiment time, also some tests were made on feed and permeate ions. Time of experiment was 180 min with the same operating conditions.