两种锰盐混凝剂除镉效能及其影响因素

Removal and influence factors of cadmium(Ⅱ) by two kinds of manganese coagulants

摘要:

针对水中微量镉的去除,利用静态实验对水合二氧化锰(HMO)和铁锰混凝剂(HFMO)的除镉效能展开研究,探讨浊度、镉初始质量浓度、pH值、时间、不同水体等因素对二者除镉效果的影响.结果表明:HMO和HFMO均能快速去除水中的微量镉,HMO的除镉效果优于HFMO,在镉初始质量浓度为1mg/L、混凝剂投量为20mg/L、pH为6.72时,HMO的除镉率可达85.04%,而HFMO在pH为8.03时除镉率仅为53.23%.在去除京密引水渠水中的镉时,HMO在除镉率和沉后浊度上的表现都优于HFMO.HMO是一种简便、有效去除水中微量镉的混凝剂.

Abstract:

A static experiment was carried out to evaluate trace cadmium(Ⅱ)removal from water by two kinds of manganese coagulants,hydrous manganese dioxide(HMO)and ferric manganese coagulant(HFMO).The effects of turbidity,initial concentration of cadmium,coagulation time and different waters on the cadmium removal were investigated.The results showed that both HMO and HFMO could eliminate cadmium quickly from water,and the effectiveness of cadmium removed by HMO was better than that by HFMO.When pH=6.72,the Cd(Ⅱ)initial concentration was 1 mg/L and the dosage of HMO was 20 mg/L,the re-moval rate of cadmium reached 85.04%.As for HFMO,when pH=8.03,the removal rate of cadmium was only 53.23%.HMO performed better than HFMO on removal of cadmium and turbidity,when two manganese coagulants were used to treat the raw water of Jingmi canal of Beijing.