Ding An, Wang Jinlong, Lin Dachao, Tang Xiaobin, Cheng Xiaoxiang, Wang Hui, Bai Langming, Li Guibai, Liang Heng
State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin, 150090, PR China.
Chemosphere. 2017 Apr;172:21-28. doi: 10.1016/j.chemosphere.2016.12.111. Epub 2016 Dec 27.
Rainwater is a nature resource, which can be widely used for non-potable and potable applications in water scared countries after appropriate treatment. Gravity-driven membrane filtration (GDM) process is a promising technology for decentralized rainwater treatment due to no backwashing, flushing and chemical cleaning. In this study, we established a single lab-scale GDM system for the stored rainwater (simulative cellar rainwater) treatment with two months operation, and a stored tap water was used as a compared system to evaluate the permeability and organics removal performance. Results showed that GDM exhibited a good performance for bacteria and turbidity removals, but the removal performance of DOC was undesirable due to the low rejection of low molecular-weight fulvic. Additionally, the permeate flux reached stable with the value of 6-6.5 L/mh during 60 days operation in the rainwater system, however, the tap water system stabilized only at 4 L/mh. Hydraulically reversible resistance accounted for large proportions (90%) of the total resistance, which indicated that the flux could be recovered by simple physical flushing. The bio-fouling layer adhered on the membrane surface was characterized at the end of the filtration experiment. Higher bio-activity with lower EPS (polysaccharides and proteins) contents of the fouling layer were found in the rainwater system compared with the control system, which was the main reason for the higher flux. These results show that rainwater can be treated in a single GDM process with low maintenance, which makes the process suitable for decentralized water supply.
雨水是一种自然资源，在经过适当处理后，可在缺水国家广泛用于非饮用水和饮用水用途。重力驱动膜过滤（GDM）工艺由于无需反冲洗、冲洗和化学清洗，是一种用于分散式雨水处理的很有前景的技术。在本研究中，我们建立了一个实验室规模的单级GDM系统，用于处理储存的雨水（模拟地窖雨水），运行两个月，并以储存的自来水作为对照系统，以评估其渗透性和有机物去除性能。结果表明，GDM在去除细菌和浊度方面表现良好，但由于对低分子量富里酸的截留率低，对溶解性有机碳（DOC）的去除性能不理想。此外，在雨水系统中运行60天期间，渗透通量达到稳定，值为6 - 6.5 L/（m²·h），然而，自来水系统仅稳定在4 L/（m²·h）。水力可逆阻力占总阻力的很大比例（90%），这表明通量可通过简单的物理冲洗恢复。在过滤实验结束时，对附着在膜表面的生物污染层进行了表征。与对照系统相比，雨水系统中污染层的生物活性较高，胞外聚合物（多糖和蛋白质）含量较低，这是通量较高的主要原因。这些结果表明，雨水可以通过单一的GDM工艺进行处理，维护成本低，这使得该工艺适用于分散式供水。
