Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China.
University of Chinese Academy of Science , Beijing 100049, China.
Environ Sci Technol. 2017 Aug 1;51(15):8544-8551. doi: 10.1021/acs.est.7b01189. Epub 2017 Jul 21.
A novel electrocoagulation membrane reactor (ECMR) was developed, in which ultrafiltration (UF) membrane modules are placed between electrodes to improve effluent water quality and reduce membrane fouling. Experiments with feedwater containing clays (kaolinite) and natural organic matter (humic acid) revealed that the combined effect of coagulation and electric field mitigated membrane fouling in the ECMR, resulting in higher water flux than the conventional combination of electrocoagulation and UF in separate units (EC-UF). Higher current densities and weakly acidic pH in the EMCR favored faster generation of large flocs and effectively reduced membrane pore blocking. The hydraulic resistance of the formed cake layers on the membrane surface in ECMR was reduced due to an increase in cake layer porosity and polarity, induced by both coagulation and the applied electric field. The formation of a polarized cake layer was controlled by the applied current density and voltage, with cake layers formed under higher electric field strengths showing higher porosity and hydrophilicity. Compared to EC-UF, ECMR has a smaller footprint and could achieve significant energy savings due to improved fouling resistance and a more compact reactor design.
一种新型的电凝聚膜反应器（ECMR）被开发出来，其中超滤（UF）膜组件被放置在电极之间，以提高出水水质和减少膜污染。用含有粘土（高岭土）和天然有机物（腐殖酸）的进料水进行的实验表明，混凝和电场的联合作用减轻了 ECMR 中的膜污染，导致水通量高于传统的电凝聚和 UF 在单独单元中的组合（EC-UF）。在 EMCR 中，更高的电流密度和弱酸性 pH 值有利于更快地生成大絮体，并有效地减少了膜孔堵塞。由于电凝聚和外加电场同时作用，形成的絮体层在膜表面上的水力阻力降低，这是由于形成的滤饼层的孔隙率和极性增加所致。形成极化滤饼层的过程受到外加电流密度和电压的控制，在较高的电场强度下形成的滤饼层具有更高的孔隙率和亲水性。与 EC-UF 相比，ECMR 的占地面积更小，由于抗污染能力的提高和更紧凑的反应器设计，可以实现显著的节能效果。
