超滤陶瓷膜处理乳化油废水的抗污染性能研究

Anti-fouling Performance of Ultrafiltration Ceramic Membrane in Treatment of Emulsified Oil Wastewater

采用膜孔径相当的TiO_2陶瓷膜和Al_2O_3陶瓷膜处理乳化油废水,从抗污染能力和过滤液水质两方面考察两种膜的过滤性能,并通过分析两种膜的结构、表面亲水性和表面电性揭示其不同过滤性能的根本原因。结果表明,TiO_2陶瓷膜具有更高的抗污染能力和COD截留率,这是由于其较高的亲水性、与乳化油相反的膜面电性以及不对称的膜孔结构所致。在此基础上对不同膜孔径的TiO_2陶瓷膜进行考察,结果表明,截留分子质量为50 ku的TiO_2陶瓷膜对乳化油废水的处理效果最佳,此时膜通量下降缓慢且恢复率高,COD截留率>95%,能有效去除废水中的乳化油,出水COD<15 mg/L,满足回用水水质标准。

Emulsified oil wastewater was treated by two types of ceramic membranes （TiO2 and Al2O3 ） with equivalent membrane aperture, and the performance was investigated in terms of anti-fouling ability and permeated water quality. Basic reason of different filtration performance of the two membranes was revealed by analysis of membrane structure, hydrophilicity and membrane surface charge. The results showed that TiO2 membrane had higher anti-fouling performance and COD rejection rate, which was due to its higher hydrophilicity, oppositely membrane surface electrical properties to emulsified oil wastewater and asymmetric membrane structure. On this basis, treatment of emulsified oil wastewater by TiO2 ceram- ic membranes with different pore sizes was investigated. It was determined that the TiO2 ceramic membrane with the molecular weight cut-off of 50 ku had the best treatment effect for emulsified oil wastewater. In this case, the membrane flux decreased slowly and the recovery rate was high with COD rejection rate of 95%, where the oil was effectively removed from the wastewater and the effluent COD was less than 15 mg/L, which met the requirement of reinjection water standard.