ABSTRACT Recycling of end-of-life polyamide-based thin film composite (TFC) membranes is gaining interest in academic and industrial contexts. The effects of chlorine exposure on the performance of polyamide membranes result in an increase in membrane permeability, whereas the solute rejection decreases. Therefore, the controlled chemical conversion of old reverse osmosis (RO) membranes has been reported by some previous papers. The objectives of this study were to assess recycling of old nanofiltration (NF) membrane, to assess the performance of the recycled membranes for a river water treatment application, and to conduct preliminary cost evaluations. Recycling technique consisted of exposing the membrane to a sodium hypochlorite solution in order to remove its polyamide layer and conversion to a low-pressure membrane. The work conducted bench scale and long-time pilot tests, and the recycled membranes showed a low fouling tendency. The difference between some results in bench- and pilot scale underscores the importance of evaluating design parameters using pilot scale units. Based on the cost analysis, the total cost of chemical recycling end-of-line NF membranes for a river water treatment is approximately 1.1% of the cost of using a new UF membrane. There is a great potential in using recycled membranes for rivers water treatments. GRAPHICAL ABSTRACT

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从旧纳滤膜转化而来的再生膜的实验室和中试规模的性能评估

摘要 报废聚酰胺基薄膜复合材料 (TFC) 膜的回收在学术和工业环境中越来越受到关注。氯暴露对聚酰胺膜性能的影响导致膜渗透性增加，而溶质截留率降低。因此，以前的一些论文已经报道了旧反渗透 (RO) 膜的受控化学转化。本研究的目的是评估旧纳滤 (NF) 膜的回收利用，评估回收膜在河水处理应用中的性能，并进行初步成本评估。回收技术包括将膜暴露于次氯酸钠溶液中以去除其聚酰胺层并转化为低压膜。该工作进行了小规模和长时间的中试，回收的膜显示出低污染趋势。基准规模和中试规模的一些结果之间的差异强调了使用中试规模单位评估设计参数的重要性。根据成本分析，用于河水处理的化学循环末端 NF 膜的总成本约为使用新 UF 膜成本的 1.1%。使用再生膜进行河流水处理具有很大的潜力。图形概要 用于河水处理的化学循环末端 NF 膜的总成本约为使用新 UF 膜成本的 1.1%。使用再生膜进行河流水处理具有很大的潜力。图形概要 用于河水处理的化学循环末端 NF 膜的总成本约为使用新 UF 膜成本的 1.1%。使用再生膜进行河流水处理具有很大的潜力。图形概要