School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore; Advanced Environmental Biotechnology Centre, Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore, 637141, Singapore; Singapore Membrane Technology Centre, Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore, 637141, Singapore.
School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore; Advanced Environmental Biotechnology Centre, Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore, 637141, Singapore; Singapore Membrane Technology Centre, Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore, 637141, Singapore.
Water Res. 2017 Mar 15;111:52-58. doi: 10.1016/j.watres.2016.12.044. Epub 2016 Dec 26.
Membrane filtration has been widely applied for water treatment, wastewater reclamation and seawater desalination. Although extensive research work has been conducted to better understand the fouling mechanism under various conditions, little has been known about the transparent exopolymer particles (TEP)-associated membrane fouling at different Na concentrations. In this study, the influence of Na concentration on the TEP formation as well as the filtration behaviors of alginate blocks was investigated. Results showed that increasing Na concentration substantially reduced the TEP formation from all types of alginate blocks, thus preventing the cake layer development on the membrane surface. As a result, the TEP-associated membrane fouling was found to be kinetically slower and much less at higher Na level. Furthermore, filtration tests of alginate blocks at freshwater and seawater conditions were also conducted, showing that TEP-associated fouling in freshwater is much server than that in seawater at the defined conditions. This study reveals that the TEP formation is significantly influenced by the chemistry condition of bulk solution and membrane fouling is profoundly affected by the TEP levels in feed water.
膜过滤已广泛应用于水处理、废水再利用和海水淡化。尽管已经进行了广泛的研究工作，以更好地了解各种条件下的污垢形成机制，但对于不同 Na 浓度下与透明胞外聚合物颗粒（TEP）相关的膜污染知之甚少。在这项研究中，研究了 Na 浓度对 TEP 形成以及海藻酸盐块过滤行为的影响。结果表明，增加 Na 浓度会大大减少所有类型的海藻酸盐块的 TEP 形成，从而防止在膜表面形成滤饼层。因此，在较高 Na 水平下，与 TEP 相关的膜污染被发现动力学更慢，程度更低。此外，还在淡水和海水条件下进行了海藻酸盐块的过滤测试，结果表明，在定义的条件下，淡水与 TEP 相关的污染比海水严重得多。本研究表明，TEP 的形成受溶液主体化学条件的显著影响，而膜污染受进料水中 TEP 水平的深刻影响。
