超滤(ultrafiltration, UF)技术能够高效除藻，但是膜污染仍然是技术应用的瓶颈。高锰酸盐预氧化常用于城市水厂高藻期的强化混凝，因此其对藻类膜污染的影响值得关注。本文研究了高锰酸钾(KMnO4)预氧化对高藻水超滤膜污染的影响，研究结果表明：KMnO4预处理后超滤对藻源有机物的去除能力(29-41%)低于单独超滤(41%)，仅对荧光组分去除有所提高；过量投加KMnO4会诱发胞外有机物(extracellular organic matter, EOM)的释放，致腐殖酸类物质含量增加；KMnO4预氧化对超滤膜污染仅有轻微的缓解作用，即使投加50μM时，末端比通量仅由0.14提高至0.19，但会增加水力不可逆膜污染；KMnO4预氧化形成的二氧化锰(MnO2)颗粒主要沉积在滤饼层中，通过物理或化学清洗均可有效去除。因此，采用KMnO4预氧化和UF技术联合处理高藻水时，应适当强化物理强度并提高清洗频率以抑制水力不可逆膜污染增长以及MnO2颗粒的沉积。

Ultrafiltration technology can efficiently remove algae, but membrane pollution is still the bottleneck of technical application. Permanganate and compound agents are often used in the enhanced coagulation technology in the algae-laden period of urban water plants. Therefore, whether it has the effect of inhibiting the algae membrane pollution is worthy of attention. In this paper, the effects of KMnO4 pretreatment on the ultrafiltration membrane pollution of the algae-laden water are studied. The results show that the removal capacity of algae-derived organics by ultrafiltration after KMnO4 pretreatment (29-41%) is lower than that of ultrafiltration alone (41%), which only improves the removal of fluorescent components; But excessive addition will induce EOM release, resulting in an increase in humic-acid content; KMnO4 pre-oxidation has a slight mitigating effect on ultrafiltration membrane pollution, even when 50μM is added, the terminal specific flux is only increased from 0.14 to 0.19, but it will increase the hydraulic irreversible membrane pollution during the filtration process; MnO2 particles formed by KMnO4 pre-oxidation are mainly deposited in the filter cake layer, which can be effectively removed by physical or chemical cleaning. Therefore, when using KMnO4 pre-oxidation and UF technology to treat algae-laden water, the physical strength should be properly strengthened and the cleaning frequency should be increased to suppress the growth of hydraulic irreversible membrane pollution and the deposition of MnO2 particles.

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