改性PVDF中空纤维膜处理汽车脱脂废水的性能研究

Study on the Performance of Modified PVDF Hollow Fiber Membrane in the Treatment of Automotive Degreasing Wastewater

采用经过亲水疏油改性的聚偏氟乙烯(PVDF)超滤膜对汽车脱脂废水进行了油水分离研究。结果表明,在跨膜压差0.08~0.10 M Pa,浓水回流量为膜初始通量的2倍,进液温度30~40℃的操作条件下,PVDF膜处理脱脂废水的分离效果最佳。在清洗液温度45℃条件下,采用纯水-HCl-Na OH+十二烷基苯磺酸钠(SDS)清洗方式可基本去除膜的不可逆污染,通量恢复率达97%。膜的稳定通量达15 L/(m^2·h),油、化学需氧量(COD)、浊度的去除率分别达到98.0%、92.9%、98.5%以上,滤液油含量低于15 mg/L、浊度低于5 NTU、COD质量浓度低于1 350 mg/L,在脱脂废水处理方面表现出巨大的应用潜力。

The polyvinylidene fluoride(PVDF) ultra-filtration membrane modified with hydrophily and oleophobicity was used to study the oil-water separation of automobile degreased wastewater.The results show that under the condition that the transmembrane pressure difference is 0.08~0.1 MPa,the return flow of concentrated water is 2 times the initial flux of the membrane and the fluid temperature is 30 ~40 ℃,the separating effect of degreasing wastewater with PVDF membrane could be the best.When the cleaning liquid is 45 ℃,the irreversible pollution of the membrane can be basically removed by using the method of pure water-HCl-NaOH+sodium dodecyl benzene sulfonate(SDS) and the flux recovery rate could achieve 91%.The stable flux of the membrane could reach 15 L/(m^2·h).The oil,chemical oxygen demand(COD) and turbidity reduction rates could achieve 98.0%,92.9%,98.5%,respectively.The content of filtrate oil is lower than 15 mg/L,turbidity is lower than 5 NTU,and COD concentration is lower than1 350 mg/L.It shows great application potential in the treatment of degreased wastewater.