污泥作为污废水处理的副产物,其产量日益增多。污泥处置前需要对污进行泥脱水处理,而污泥调理是污泥脱水前相当重要的步骤。研究人员以羧甲基壳聚糖(CMCTS)、丙烯酰胺(AM)和甲基丙烯酰氧乙基三甲基氯化铵(DMC)为单体,偶氮二异丁脒盐酸盐(V-50)作为引发剂,通过紫外光引发聚合方式合成新型阳离子型污泥脱水剂CMCTS-g-CPAM。同时以光引发剂浓度、pH、光照时间为考察对象,CMCTS-g-CPAM特性粘度为响应值,采用响应面法(RSM)对CMCTS-g-CPAM污泥脱水剂的制备条件进行优化。通过响应面分析得到最佳合成条件：光照时间为2h、光引发剂浓度为0.04%(体积分数)、pH为8。接枝共聚物的红外光谱(FT-IR)和核磁共振(1H-NMR)表征表明AM和DMC已成功接枝到CMCTS。最后将合成产物应用于污泥脱水,实验结果表明其具有良好的污泥脱水性能。在絮凝剂投加量和pH分别为30mg/L和10时,污泥比阻降至1.96×1013m/kg,滤饼含水率降至79.28%。

Excess sludge, product of sewage treatment, is increasingly produced. Sludge decontamination is required before sludge disposal, and sludge conditioning is a very important step. Cationic sludge dehydrating agent of CMCTS-g-CPAM was synthesized using Carboxymethyl chitosan (CMCTS), acrylamide (AM) and methacryloyloxyethyltrimethylammonium chloride (DMC) as monomers, azobisisobutylphosphonium hydrochloride (V-50) as an initiator through initiating polymerization by ultraviolet light. The preparation conditions of CMCTS-g-CPAM sludge dehydrating agent were optimized by response surface methodology (RSM) taking the photoinitiator concentration, pH and illumination time as the object of investigation, the intrinsic viscosity of CMCTS-g-CPAM as the response value. The optimal illumination time, photoinitiator concentration, and pH of respectively 2h, 0.04% (volume fraction), and 9 were obtained by response surface analysis. FT-IR and 1H-NMR of the graft copolymer indicated that AM and DMC were successfully grafted to CMCTS. Finally, the synthesized product was applied to sludge dewatering. The experimental results showed that it has good sludge dewatering performance. Sludge specific resistance decreased to 1.96×1013m/kg, and the moisture content of the filter cake decreased to 79.28%,at the flocculant dosage and pH of 30mg/L and 10, respectively.

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国家自然科学基金项目（51508268）；江苏省自然科学基金项目（BK20150951）；国家重点研发计划资助（2017YFB0602500）；中国博士后科学基金资助项目（2016M591835）