Effectiveness of PAC pre-deposition and pre-adsorption to remove the algal organic matter (AOM) extracted fromProrocentrum donghaiense was investigated. The differences in membrane flux, fouling resistance, hydrophilicity and roughness of membrane surface between direct ultrafiltration (UF), PAC pre-deposition-UF and PAC pre-adsorption-UF were analyzed. The effects of pore structure and deposition doses on AOM removal rates and membrane fouling were evaluated. It was found that DOC and UV254 removal rates could be enhanced by pre-deposition and pre-adsorption, and the former was more favorable for AOM removal than the latter. Mesoporous PAC had a better effect on the improvement of AOM removal rate than microporous PAC during pre-deposition treatment. Compared with direct UF, the removal rates of DOC and UV254 were increased by 25.1% and 33.6%, respectively, when the deposition amount of mesoporous PAC was 0.4g/L. The analysis of UV absorbance ratio index (URI) confirmed that the aromatic groups could be selectively removed over aliphatic groups using PAC pre-deposition and pre-adsorption. The cake layer resistance (Rc) and the pore resistance (Rp) were decreased by 39.6% and 81.2%, respectively, when PAC pre-deposition were used before AOM UF. Membrane fouling rate was reduced by PAC pre-deposition because a PAC cake layer was formed between UF membrane and AOM, resulting in the mitigation of irreversible fouling.%以东海原甲藻分泌的藻类有机物(AOM)为研究对象,研究粉末活性炭预沉积和预吸附两种膜前预处理手段对海水中AOM的去除作用,对比分析AOM直接超滤、预沉积和预吸附后再超滤时膜通量、膜阻力分布、膜表面亲疏水性和粗糙度的变化,探讨粉末活性炭孔隙结构、沉积量对AOM去除效果及超滤膜污染的影响.结果表明,活性炭预沉积和预吸附能够提高超滤膜对含AOM海水中DOC和UV254的去除率,预沉积对AOM的去除作用优于预吸附,介孔活性炭较微孔活性炭的预沉积效果更好,当介孔活性炭PAC2的沉积量为0.4g/L时,DOC和UV254的去除率较直接超滤分别提高了25.1%和33.6%.紫外吸收比指数(URI)分析表明,活性炭预沉积和预吸附对有机物的去除作用具有选择性,AOM中芳香族物质较脂肪族羧基类物质更易被除去.粉末活性炭预沉积下AOM超滤时的滤饼层污染阻力(Rc)和膜孔堵塞阻力(Rp)较直接超滤分别降低了39.6%和81.2%,活性炭在超滤膜表面形成的滤饼层结构将AOM与超滤膜进行了隔离,能够减缓膜污染速率,对于控制膜的不可逆污染亦具有重要作用.
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