超滤/反渗透双膜技术深度处理印染废水

Treatment of textile wastewater using ultratfiltration and reverse osmosis dual membrane system

由于印染废水具有高盐度,可生化性差,使常规方法难于处理完全。采用超滤和反渗透双膜技术处理实际印染废水,考察了不同超滤膜对废水的预处理性能,研究了BW 30和CPA2两种反渗透膜在不同操作条件下对印染废水的处理效果,并分析了相关膜通量下降的原因。结果表明,超滤能有效地去除废水浊度和大分子有机物,为反渗透提供良好的进水水质。两种反渗透膜的产水化学需氧量(COD)均小于10 mg/L,电导率小于80μS/cm,其对有机物和盐的去除率分别可达99%和93%以上,显示该产水能回用于大部分印染工序。BW 30膜产水水质稍好于CPA2,但通量低于CPA2。

Ultrafiltration and reverse osmosis combined membrane processes were applied for in the textile wastewater treatmeat and reuse. As pretreatment, ultrafiltration had good performance on removal of turbidity and organic matters with high molecular weight, which could guarantee good quality of feed water for reverse osmosis. Two kinds of reverse osmosis membranes （BW30, CPA2） were tested and compared later by carrying out the lab-test under different operating pressures, times and temperatures. It appeared that permeate had COD value lower than 10 mg/L and conductivity no more than 80 μS/cm. The rejection for COD and salt could reach as high as 99% and 93%, respectively. Permeate of both two membranes could be recycled to most of dyeing process. Compared with CPA2, BW30 had a little better quality of permeate, but its flux was somewhat lower. At last, permeate flux decrease due to membrane fouling was also analyzed.