Xue Wen-Jing, Li Wen-Jiang, Liu Juan, Ma Bai-Wen
College of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao 266042, China.
Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Huan Jing Ke Xue. 2019 Feb 8;40(2):730-737. doi: 10.13227/j.hjkx.201806037.
Owing to the small land use and high pollutant removal efficiency, the integrated ultrafiltration (UF) membrane process has been gradually applied in water treatment. However, not only would the membrane surface be damaged by the commonly used granular adsorbents over time, but these types of adsorbents are expensive, such as nano zerovalent iron, carbon nanotubes, etc. To overcome these disadvantages, the loose Al-based flocs were directly injected into the membrane tank in the presence of humic acid and Miyun reservoir water. Results showed that severe membrane fouling was induced by HA alone, and the transmembrane pressure (TMP) significantly increased to 76.4 kPa after 12 d of operation. However, it dramatically decreased to 10.1 kPa after washing with tap water on day 13, indicating that the cake layer was the main fouling mechanism. The average HA removal efficiency was only 23.3% during filtration. In addition, the performance of the integrated flocs-membrane process could be influenced by floc dosage, injection frequency, and solution pH. The integrated membrane performed well with flocs (43.2 mmol·L) continuously injected at pH 6.0 (aeration rate at 0.3 L·min). The corresponding TMP only increased to 19.5 kPa after running for 12 d, which decreased to 5.6 kPa after washing with tap water on day 13. The average HA removal efficiency increased to 61.2%. Additionally, serious membrane fouling was also induced by Miyun reservoir alone. The TMP increased to 38.0 kPa on day 12, while it decreased to 3.8 kPa after washing with tap water on day 13. The cake layer was also the main fouling mechanism, and the average pollutant removal efficiency was only 7.5%. With floc continuously injected, however, the TMP only increased to 6.1 kPa on day 12. After washing with tap water, the TMP decreased to 2.3 kPa on day 13, and the average pollutant removal efficiency was as high as 58.6%. Based on the excellent membrane performance, the integrated membrane process exhibited potential application in drinking water treatment.
由于占地面积小且污染物去除效率高，集成超滤（UF）膜工艺已逐渐应用于水处理领域。然而，常用的颗粒吸附剂不仅会随着时间的推移损坏膜表面，而且这些类型的吸附剂价格昂贵，如纳米零价铁、碳纳米管等。为了克服这些缺点，在腐殖酸和密云水库水存在的情况下，将松散的铝基絮凝物直接注入膜池中。结果表明，单独的腐殖酸会导致严重的膜污染，运行12天后，跨膜压力（TMP）显著增加至76.4 kPa。然而，在第13天用自来水冲洗后，TMP急剧下降至10.1 kPa，这表明滤饼层是主要的污染机制。过滤过程中腐殖酸的平均去除效率仅为23.3%。此外，絮凝物 - 膜集成工艺的性能可能会受到絮凝剂用量、注入频率和溶液pH值的影响。在pH值为6.0（曝气速率为0.3 L·min）的情况下连续注入絮凝物（43.2 mmol·L）时，集成膜表现良好。运行12天后，相应的TMP仅增加至19.5 kPa，在第13天用自来水冲洗后降至5.6 kPa。腐殖酸的平均去除效率提高到61.2%。此外，单独的密云水库水也会导致严重的膜污染。第12天TMP增加至38.0 kPa，而在第13天用自来水冲洗后降至3.8 kPa。滤饼层也是主要的污染机制，污染物的平均去除效率仅为7.5%。然而，在连续注入絮凝物的情况下，第12天TMP仅增加至6.1 kPa。用自来水冲洗后，第13天TMP降至2.3 kPa，污染物的平均去除效率高达58.6%。基于优异的膜性能，集成膜工艺在饮用水处理中展现出潜在的应用前景。
