PAM-AA与金属离子复合絮凝剂的合成及其在污泥脱水中的应用

以丙烯酰胺(AM)、 丙烯酸(AA)和硫酸铝为原料, 采用水溶液聚合法合成Al³⁺复合高分子絮凝剂（PAM-AA）. 通过正交实验确定最佳聚合条件为： m(AM)∶m(AA）=5∶3, 反应温度为65 ℃, 搅拌时间5 h, 引发剂的加入量占单体质量3%, 产率可达96.3%. 在此基础上合成Ca²⁺,Mg²⁺和Fe³⁺复合高分子絮凝剂, 利用红外光谱（IR）、 X射线衍射（XRD）、 扫描电子显微镜（SEM）等方法对产物的结构和形貌进行表征. 将复合高分子絮凝剂与杀菌剂N,N-二甲基十二烷基苄基氯化铵（1227）用于市政生活污泥脱水中, 通过滤饼含水率和污泥比阻, 对比研究聚合氯化铝（PAC）、 PAM-AA和硫酸铝机械混合物以及Al³⁺复合高分子絮凝剂对市政污泥脱水性能的影响. 结果表明, Al³⁺复合高分子絮凝剂与1227协同使用, 可使污泥滤饼含水率降至63.8%, 效果较好. 

Synthesis of PAM-AA and Metal Ion Composite Flocculant and Its Application in Sludge Dewatering

Al³⁺ composite polymeric flocculant （PAM-AA） was synthesized by  aqueous solution polymerization with acrylamide (AM), acrylic acid (AA) and Al₂(SO₄)₃ as raw materials. The optimum ploymerization conditions were determined by orthogonal experiment  as  m(AM)∶m(AA）=5∶3, reaction temperature  65 ℃ and  stirring time  5 h. The yield could reach  96.3% when the amount of the initiator was 3% of the mass of monomer.  On this basis, Ca²⁺,Mg²⁺ and Fe³⁺ composite polymeric flocculant were synthesized. The structure and morphology of Al³⁺ composite polymeric flocculant were characterized by infrared spectrum (IR), X-ray diffraction (XRD), scanning electron microscope (SEM), respectively. Al³⁺ composite polymeric flocculant and N,N-dimethyl, dodecyl, benzyl ammonium chloride (1227) were applied in municipal sludge dewatering. Through the filter cake moisture content (FCMC) and the specific resistance in filtration (SRF), we compared the effects of  the commercial flocculant polyaluminium chloride (PAC),  the mixture between Al₂(SO₄)₃ and PAM-AA on the dewatering performance of municipal sludge. The results show that the combination of Al³⁺ composite polymer flocculant and 1227 can reduce the FCMC of sludge filter cake to 63.8%, and the effect is good.