Influencing Factors of DCMD for Treatment of RO Concentrate Wastewater on Water Reclamation

Direct Contact Membrane Distillation(DCMD) device with PVDF as the core was introduced to treat concentrated Reverse-Osmosis(RO) wastewater on water reclamation. Effects of feed temperature, feed flow rate and permeate flow rate on flux were investigated. Furthermore, variation low of permeate flux and the main water quality during long-term membrane distillation(MD) performance were discussed. It can be concluded from the result that the permeate flux were increased with the feed temperature. When the temperature difference between hot-side and cool-side reached 35 degrees C, the permeate flux was 7.15 kg/(m(2).h), and then the growth trend of flux slowed down. The permeate flux were increased with the increase of feed flow rate and permeate flow rate, and the peak reached 8.2 kg/(m(2).h) in the whole process. The permeate flux stabilized at 7.1 similar to 8.36 kg/(m(2).h) during 16 hours long term experiment performance and the permeate water quality were kept steadily.