State Key Laboratory of Separation Membranes and Membrane Process, Tianjin Polytechnic University, Tianjin, 300387, China; School of Environmental and Chemical Engineering, Tianjin Polytechnic University, Tianjin, 300387, China.
Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW, 2007, Australia.
Water Res. 2019 Jun 15;157:155-166. doi: 10.1016/j.watres.2019.03.052. Epub 2019 Mar 26.
A new hybrid system was developed in this study for the treatment of drinking water consisting of pre-coagulation using polyaluminium chloride (PACl) and membrane filtration (MF) with sponge cubes acting as biomass carriers (P-SMF). When compared to a conventional MF (CMF) and a MF after coagulation by utilizing PACl (P-MF), better removal of nutrients, UV and dissolved organic carbon (DOC) (>65%) was obtained from the P-SMF. The accumulation of biopolymers (including polysaccharides and proteins), humic substances, hydrophilic organics, and other small molecular weight (MW) organic matter in the CMF led to the most severe membrane fouling coupled with the highest pore blocking and cake resistance. Pre-coagulation was ineffective in eliminating small MW and hydrophilic organic matter. Conversely, the larger MW organics (i.e. biopolymers and humic substances), small MW organics and hydrophilic organic compounds could be removed in significantly larger quantities in the P-SMF by PACl coagulation. This was achieved via adsorption and the biodegradation by attached biomass on these sponges and by the suspended sludge. Further analyses of the microbial community indicated that the combined addition of PACl and sponges generated a high enrichment of Zoolgloea, Amaricoccus and Reyranella leading to the reduction of biopolymers, and Flexibacter and Sphingobium were linked to the degradation of humic substances. Moreover, some members of Alphaproteobacteria in the P-SMF may be responsible for the removal of low MW organics. These results suggest that the pre-coagulation process coupled with adding sponge in the MF system is a promising technology for mitigating membrane fouling.
本研究开发了一种新的饮用水处理混合系统，该系统由聚合氯化铝（PACl）预混凝和海绵块作为生物载体的膜过滤（P-SMF）组成。与传统的膜过滤（CMF）和 PACl 混凝后的膜过滤（P-MF）相比，P-SMF 对营养物质、紫外线和溶解有机碳（DOC）的去除效果更好（>65%）。CMF 中生物聚合物（包括多糖和蛋白质）、腐殖质、亲水性有机物和其他低分子量（MW）有机物的积累导致最严重的膜污染，同时伴随着最高的孔堵塞和滤饼阻力。预混凝对消除低 MW 和亲水性有机物无效。相反，P-SMF 中的 PACl 混凝可去除更多的大 MW 有机物（即生物聚合物和腐殖质）、小 MW 有机物和亲水性有机化合物。这是通过吸附和附着在这些海绵上的生物量以及悬浮污泥对这些物质的生物降解来实现的。对微生物群落的进一步分析表明，PACl 和海绵的联合添加导致Zoogloea、Amaricoccus 和 Reyranella 的高度富集，从而减少了生物聚合物的含量，而 Flexibacter 和 Sphingobium 则与腐殖质的降解有关。此外，P-SMF 中的一些α变形菌可能负责去除低 MW 有机物。这些结果表明，预混凝工艺与在 MF 系统中添加海绵相结合是一种有前途的减轻膜污染的技术。
