以聚铝为混凝剂的混凝再稳现象试验研究

Experimental study on restabilization of coagulation with PAC as coagulant

针对D江不同时期的水质开展试验,研究了聚合氯化铝作为混凝剂时的再稳现象。结果表明:不能仅通过常规投加量的混凝效果、有效铝含量、盐基度、水解聚合形态等指标来衡量聚合氯化铝的产品性能,还应考察其是否易出现混凝的再稳现象。以聚合氯化铝为混凝剂的混凝再稳现象,与混凝剂本身的电荷密度、悬浮颗粒物表面电荷、Zeta电位、混凝剂投加量、不适合的剪切搅拌和原水中的有机物浓度等因素有关。

Coagulation experiments were carried out on the water quality of D River in different periods,the coagulation restabilization was studied by using polyaluminium chloride (PAC) as coagulant. The results showed that the properties of PAC could not be measured only by coagulation effect under conventional dosage,effective aluminium content,basicity,hydrolysis and polymerization morphology,but also by whether PAC was prone to restabilization. The restabilization phenomenon of coagulation with PAC as coagulant was related to the charge density of coagulant itself,surface charge of suspended particulate matter,Zeta potential,coagulant dosage,improper shear stirring and organic matter concentration in raw water.