PAM复配混凝剂对高岭土体系混凝过程的影响

为了解决无机混凝剂在混凝过程中的不足，选用AlCl3及其与2种不同阴离子度的PAM复配的混凝剂对高岭土体系进行混凝实验研究。结果表明：使用AlCl3做混凝剂，当投加量（以Al计）为0.1 mmol·L-1时，剩余浊度达到最低；平衡时粒径达到700 μm，且随着破碎时间的延长，絮体再生长结束后的粒径逐渐减小，在破碎时间为6.0 min时，絮体粒径最终能恢复到300 μm左右。以PAM-1复配的AlCl3为混凝剂，在投加量为0.1 mmol·L-1时，剩余浊度最低；经慢速搅拌10 min，絮体平衡时的粒径较使用AlCl3作混凝剂时略小，但随着PAM-1浓度的增大，絮体破碎后的恢复能力逐渐增大。当PAM-1与Al的比例为10%，破碎1.0 min时，絮体粒径最终可以恢复到600 μm左右。以PAM-2复配的AlCl3为混凝剂时，由于PAM-2的阴离子度过高，需要更多的混凝剂中和体系中存在的负电荷，所以在混凝剂浓度为0.2 mmol·L-1时，剩余浊度才达到最低。

Effects of PAM on coagulation process in kaolin system using composite coagulants

To improve the coagulation performance of kaolin systems,AlCl3 and two composite coagulants were selected as coagulants. The results indicated that the residual turbidity decreased to the minimum when the coagulant dosage was 0.1 mmol·L-1 (calculated as Al) using AlCl3 as coagulant. The floc size was 700 μm after the growth period,and the floc size after the regrowth period decreased as the breakage period was prolonged. When the breakage period was 6.0 min,the floc size after regrowth was approximately 300 μm. When using the composite coagulants prepared by dissolving PAM-1 in AlCl3 solution,the residual turbidity also decreased to the minimum when the coagulant dosage was 0.1 mmol·L-1. The recovery factor increased with the concentration of PAM-1. When the ratio of PAM-1 to Al was 10%,the floc size after regrowth reached approximately 600 μm. When using the composite coagulants prepared by dissolving PAM-2 into AlCl3 solution,the optimum dosage was approximately 0.2 mmol·L-1 due to the larger amount of negative charge.