Graduate School of Engineering, Nagasaki University, Nagasaki 852-8521, Japan.
Faculty of Science & Technology, Ryukoku University, Shiga 520-2194, Japan.
Int J Environ Res Public Health. 2018 Apr 19;15(4):799. doi: 10.3390/ijerph15040799.
A new membrane fouling control technique using ozonated water flushing was evaluated for direct nanofiltration (NF) of secondary wastewater effluent using a ceramic NF membrane. Experiments were conducted at a permeate flux of 44 L/m²h to evaluate the ozonated water flushing technique for fouling mitigation. Surface flushing with clean water did not effectively remove foulants from the NF membrane. In contrast, surface flushing with ozonated water (4 mg/L dissolved ozone) could effectively remove most foulants to restore the membrane permeability. This surface flushing technique using ozonated water was able to limit the progression of fouling to 35% in transmembrane pressure increase over five filtration cycles. Results from this study also heighten the need for further development of ceramic NF membrane to ensure adequate removal of pharmaceuticals and personal care products (PPCPs) for water recycling applications. The ceramic NF membrane used in this study showed approximately 40% TOC rejection, and the rejection of PPCPs was generally low and highly variable. It is expected that the fouling mitigation technique developed here is even more important for ceramic NF membranes with smaller pore size and thus better PPCP rejection.
采用臭氧水冲洗的新型膜污染控制技术，用于通过陶瓷纳滤膜直接纳滤（NF）二级废水出水。在 44 L/m²h 的渗透通量下进行实验，以评估臭氧水冲洗技术对污染缓解的效果。用清洁水进行表面冲洗不能有效地从 NF 膜上去除污染物。相比之下，用臭氧水（4mg/L 溶解臭氧）进行表面冲洗可以有效地去除大部分污染物，恢复膜的渗透性。这种使用臭氧水的表面冲洗技术能够限制跨膜压力在五个过滤周期内增加 35%，从而限制污染的进展。本研究的结果还进一步强调需要进一步开发陶瓷纳滤膜，以确保在水再利用应用中充分去除药品和个人护理产品（PPCPs）。本研究中使用的陶瓷纳滤膜对 TOC 的去除率约为 40%，而 PPCPs 的去除率通常较低且变化较大。预计这里开发的污染缓解技术对于孔径更小、PPCP 去除率更好的陶瓷纳滤膜更为重要。
