Abstract Integrated ultrafiltration (UF) membranes are a promising technology in water treatment. However, commonly used granular adsorbents are only injected into the membrane tank once, which not only results in serious membrane surface damage, but also severe membrane fouling due to the low utilization efficiency of adsorbents over time. To overcome these disadvantages, loose Fe-based flocs, which display better sludge discharge than Al-based flocs, were investigated to improve integrated UF membrane performance under different injection frequencies with humic acid (HA) and reservoir water. Results showed that multiple dynamic floc layers were formed with batch injections and a critical injection frequency existed. When the injection frequency was too low, membrane fouling was induced by the formation of a dense HA cake layer on the floc surface. In contrast, it was alleviated when the HA molecules entering the membrane tank did not exceed the adsorption ability of the flocs injected each time. HA removal efficiency also increased with increasing injection frequency due to the improvement of floc utilization efficiency. With changing floc characteristics, better membrane performance was induced, especially under acidic conditions, which was ascribed to the higher positive surface charge and specific surface area of flocs. Raw water experiments further confirmed the excellent membrane performance based on high pollutant removal efficiency and minor membrane fouling. According to the outstanding membrane performance, this novel integrated floc-membrane process has great application potential in water treatment.

中文翻译：

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铁基絮凝膜一体化工艺减轻腐植酸和水库水对超滤膜的污染

摘要 集成超滤（UF）膜是水处理中一种很有前途的技术。然而，常用的颗粒吸附剂只注入膜槽一次，不仅会导致膜表面严重损坏，而且随着时间的推移，由于吸附剂利用效率低，膜污染严重。为了克服这些缺点，研究了松散的铁基絮凝物，其污泥排放比铝基絮凝物更好，以提高腐植酸 (HA) 和水库水在不同注入频率下的综合超滤膜性能。结果表明，分批注入形成多个动态絮凝层，存在临界注入频率。当注入频率过低时，膜污染是由絮体表面形成致密的 HA 滤饼层引起的。相比之下，当进入膜槽的HA分子不超过每次注入的絮凝物的吸附能力时，则有所缓解。由于絮体利用效率的提高，HA去除效率也随着注入频率的增加而增加。随着絮体特性的变化，膜性能更好，尤其是在酸性条件下，这归因于絮体具有更高的表面正电荷和比表面积。原水实验进一步证实了基于高污染物去除效率和轻微膜污染的优异膜性能。根据优异的膜性能，