不同铝聚合形态对聚合铝混凝效果的影响

通过氯化铝(铝单体或初聚物形态Ala)、高Alb含量聚合铝(中等聚合形态Alb)、高Alc含量聚合铝(铝溶胶等高聚合形态Alc)和工业PACl(不同聚合度铝的混合形态Alabc)对某水厂沉后水实际水样进行烧杯混凝实验,依据絮体生长状况、浊度、UV254、颗粒数和过滤指数等参数综合评价不同铝形态的混凝作用效果,从而得出铝的最佳混凝形态.结果表明,高Alb含量聚合铝对浊度去除较好;而高Alc含量聚合铝对于颗粒物和UV254的去除效果较佳.

Comparative Study on the Coagulation of PACl with Different Contents of Aluminum Polymeric Species

Based on the Ferron assay of aluminum species, jar test and filterability index, four types of PACl products of Al_a, Al_b, Al_c, and Al_abc are investigated on raw water samples from settling tank of water plant, which denote the different dominant aluminum species of AlCl₃ for monomer or oligomer, PACl with high Al₁₃ contents for mediate polymer of Al_b, PACl with high Al_c contents for aluminum high polymer or Al(OH)₃ sol, and industrial PACl for the mixed aluminum polymeric species with variety of alkalinity of Al_a, Al_b and Al_c, respectively. Multiple parameters including the residual turbidity, UV₂₅₄, particles removal, filterability index as well as the floc formation kinetics are monitored to make a comprehensive evaluation of their coagulation and settling-filtration performance. It indicates that PACl with high Al_b contents demonstrate their predominant ability in the turbidity removal, whereas PACl with high Al_c contents prefer to cutting down the particles and UV₂₅₄.