混凝对微滤膜处理含磷废水的影响

采用直接微滤和混凝-微滤2种工艺对高浓度含磷废水进行了处理.结果表明,混凝预处理减轻了膜孔堵塞污染,改善了膜表面沉积层的存在形态,提高了膜的渗透通量;与原水直接微滤相比,混凝-微滤组合工艺改进了出水水质,磷酸盐的去除率从11.0%提高到99.7%,出水满足国家一级排放标准;经过相同方法清洗后,混凝-微滤工艺的膜通量能恢复到初始通量的90%以上,而直接微滤工艺的膜通量只能恢复到初始通量的72%.

Effect of Coagulation on the Performance of Microfiltration in Treating Phosphorus-Containing Wastewater

Treatment of high-concentration phosphorus-containing wastewater produced from automobile painting-industry using microfiltration with and without coagulation pretreatment was studied.The results show that the membrane fouling decreased by reducing the extent of pore plugging and improving the shape of cake layer formed on membrane surface and the permeate flux increased with coagulation as pretreatment.In comparison with direct microfiltration(without coagulation),pretreatment with lime improves removal of phosphate from 11.0% to 99.7%.The permeate obtained from coagulation and microfiltration can meet the national discharge standard and be reused under very safe conditions.With the same cleaning method,the recovery of permeate flux is approximately 18% greater than that of without coagulation pretreatment,which may be due to the differences in the shape of deposited cake and the extent of irreversible fouling.