混凝沉淀法饮水除砷研究

Study of Arsenic Removal from Drinking Water by Coagulation-Sedimentation Method

本文采用两种混凝剂—氯化铁和硫酸铝对两种水质中两种价态的砷进行了除砷试验。结果表明:1.氯化铁去除很软水和硬水中0.34±0.01mg/L As^(5+)的适宜剂量分别为10和20mg/L左右;硫酸铝分别为40和60mg/L左右;2.氯化铁去除两种水质中0.33±0.01mg/L As^(3+)的适宜剂量分别为20和65mg/L左右;硫酸铝除As^(3+)的效率极低;3.As^(3+)用2.5mg/L的氯氧化后,其去除率与As^(5+)相似;4.两种混凝剂的除砷吸咐容量与砷平衡浓度的关系非常符合弗兰德利希吸咐等温式,说明其除砷机理是以吸咐沉淀为主。

In this study the arsenic removing test for the remove of two different kinds of valence arsenic under two different water qualities was conducted with two different coagulants——ferric chloride and alum. Experimental results show that: 1 , The suitable doses of ferric chloride for 0.34+0.01mg/L of As^(5+) in quite soft water or hard water are 10 and 20 mg/L respectively, and the suitable doses of alum are respectively about 40 and 60mg/L; 2, The suitable doses of ferric chloride are respctively about 20 and 65 mg/L for 0.33±0.01mg/L of As^(3+) in two different water qualities. 3, The effect of As^(3+) removal is similar to As^(5+), after As^(3+) oxidated by 2.5mg/L chlorine.