膜滤特性对混凝-超滤组合去除双酚A的影响

针对水中的内分泌干扰物污染问题,研究了膜滤过程中膜孔径大小对双酚A(BPA)的去除特性,以及聚合氯化铝(PACl)混凝与超滤组合方法对BPA去除效能的影响。结果表明,膜孔径越小、初始BPA含量越小,BPA去除率越大,截留相对分子质量小于10~3的膜滤后BPA的最高去除率达到93.08%。在较广pH范围内(4.08、7.25和10.05),随着膜孔径增大,BPA的去除率逐渐减小,中性(pH=7.25)或酸性(pH=4.08)条件下更有利于膜滤去除BPA;PACl投加量为12 mg/L时,pH为7左右时,BPA去除率达到最大的37.68%。增加腐殖酸的含量并不利于BPA的去除。相较于单独的混凝或超滤工艺,混凝-超滤组合工艺有利于提高BPA的去除率并降低膜污染。

Effect of Membrane Filtration Characteristics on Bisphenol A Removal Efficiency by Coagulation-Ultrafiltration Combined Process

Aimed at the problem of contamination of endocrine disruptors in water. The removal characteristics of bisphenol A(BPA) by the membrane pore size during membrane filtration, and the effect of combined coagulation and ultrafiltration on BPA removal efficiency were studied. The results indicated that, the smaller the membrane pore size and the initial BPA content, the higher the BPA removal rate, the highest removal rates of BPA could reach 93.08% after membrane filtration when cut-off relative molecular mass was less than 10~3. With the membrane pore size increasing, the removal rate of BPA gradually decreased in the wide range of pH(4.08, 7.25 and 10.05), neutralization(pH=7.25) or acidity(pH=4.08) was beneficial for BPA removal. When the dosage of aluminum sulfate was 12 mg/L and pH was 7, the removal rate of BPA was the highest as 37.68%. However, increasing humic acid content was not beneficial for BPA removal. Compared with single coagulation or ultrafiltration processes, the combined technology of coagulation-ultrafiltration was beneficial to increase the removal rate of BPA and reduce membrane fouling.