【摘要】 以硫酸铝为混凝剂、聚丙烯酰胺(PAM)为助凝剂,考察了不同混凝剂投量下絮体破碎再絮凝的出水浊度变化以及污泥回流量对除浊效果的影响。结果表明:当混凝剂投量为5、7.5mg/L时,可使再絮凝浊度低于初始絮凝浊度,在此混凝剂投量下,回流一定量的污泥可进一步优化再絮凝效果,而PAM的加入会产生一定的胶体保护作用;当混凝剂投量>10 mg/L时,再絮凝浊度高于初始絮凝浊度,在此情况下回流污泥会使再絮凝浊度进一步升高,投加PAM可在一定条件下逆转这种恶化倾向。更多还原

【Abstract】 Variation of turbidity in effluent from breakage and regrowth of flocs with various coagulant dosages and the effect of sludge recycle flow rate on turbidity removal were investigated with aluminum sulfate as coagulant and polyacrylamide as coagulant aids. The results showed that when the dosage of coagulant was 5 mg/L and 7. 5 mg/L,the turbidity during reflocculation was inferior to the turbidity during initial flocculation,and the reflocculation effect could be optimized by recycling a certain amount of sludge. The addition of polyacrylamide could provide colloidal protection. When the dosage of coagulant was greater than 10 mg/L,the turbidity during reflocculation was superior to the turbidity during initial flocculation. In this case,the turbidity during reflocculation was increased by recycling sludge. Under certain condition,additional dosage of polyacrylamide could reverse this deterioration trend.更多还原