从铝形态转化角度分析AlCl3的混凝性能

应用Ferron逐时络合比色法,从铝形态转化角度对AlCl3混凝性能进行了研究. 结果表明,AlCl3的混凝性能与其发生二次水解反应后水解产物形态中的Alb所占比例成正比,而影响AlCl3水解产物中Alb所占比例的主要因素是体系中的pH. 混凝过程中的水系组成及浓度和AlCl3投加量的不同均会引起体系pH变化,从而影响AlCl3水解产物中Alb所占比例,最终影响AlCl3的混凝效果.AlCl3在混凝过程中所表现出的水解程度大、产生H+多的特征,使其在高碱度体系和高浓度有机酸体系的污水处理中效率更高.

Coagulation Property of Aluminum Chloride from the Perspective of Speciation Conversion of Aluminum

The Al-Ferron timed complex-colorimetric method was applied to investigate the coagulation property of aluminum chloride (AlCl₃) from the perspective of speciation conversion of aluminum. The results indicate that the coagulation efficiency of AlCl₃ positivelycorrelates with the content of Al_b species, and pH is a main controlling factor influencing speciation distribution of AlCl₃. Both the composition and concentration of the system and the dosage of AlCl₃ may cause changes of pH in thecoagulation system, which can influence Al_b content of the hydrolysis products, therefore influencing coagulation efficiency of AlCl₃. AlCl₃ can hydrolyze to a larger extent and can produce more H⁺than other poly-aluminums, soit treats wastewater of high alkalinity and organic acid of high concentration more efficiently.