针对某地地下水溶解性硅、铁和锰同时超标的情况，开展了曝气 + 三氯化铁、次 氯酸钠 + 三氯化铁、曝气 + 氢氧化钙、次氯酸钠 + 氢氧化钙及曝气 + 氢氧化钙/三氯化铁 等技术同步去除水中溶解性硅、铁和锰的研究． 曝气氧化方法的试验结果表明:以三氯化 铁为混凝剂时，不能实现硅、铁和锰的同步去除;以氢氧化钙为混凝剂时，可实现硅、铁和 锰的同步去除(当氢氧化钙投加量为 500 mg/L 时，硅、铁和锰的去除率分别为 51. 2%、 84. 3%和 90. 9%)，但出水 pH 值不符合水质要求;采用氢氧化钙/三氯化铁复配混凝剂 时，可进一步强化硅、铁和锰的同步去除，同时出水浊度均小于 0. 71NTU，pH 值符合水质 要求． 采用次氯酸钠为氧化剂的试验结果表明:以三氯化铁为混凝剂时，可有效去除铁和 锰，但对硅和浊度的去除效果较差;以氢氧化钙为混凝剂时，可实现硅、铁和锰的同步去 除，且对浊度有较好的去除效果，但出水呈较强碱性，不符合水质要求． 综合考虑，推荐采 用曝气 + 氢氧化钙/三氯化铁复配混凝剂作为同步去除地下水中硅、铁和锰的方法． 当氢氧化钙投加量为 500mg/L、三氯化铁投加量(以 Fe³⁺ 计)为 22. 4mg/L 时，出水残余硅、铁 和锰的含量分别为 13. 74、0. 15 和 0. 005 mg/L，pH 值为 8. 5，出水浊度为 0. 65 NTU，符合 GB 5749—2006《生活饮用水卫生标准》的要求．

In face with the situation in which soluble silicate,Fe(Ⅱ) and Mn(Ⅱ) simultaneously exceed the standards of the groundwater in a certain area,a study has been performed of aeration + ferric chloride，sodium hy- pochlorite + ferric chloride,aeration + calcium hydroxide，sodium hypochlorite + calcium hydroxide and aeration + sodium hypochlorite coupled with ferric chloride to realize the simultaneous removal of the soluble silicate，Fe(Ⅱ) and Mn(Ⅱ).The results of the aeration oxidation method show that (1) a satisfactory simultaneous removal effect of silicon,iron and manganese cannot be obtained with ferric chloride being the coagulant; (2) with calcium hy- droxide being the coagulant,this simultaneous removal can be achieved (when the dosage of calcium hydroxide is 500mg/L,the removal rates of the soluble silicate，Fe(Ⅱ) and Mn(Ⅱ) are 51. 2%,84. 3% and 90. 9%,re- spectively),but with a result of pH value surpassing the standard; and (3) application of the sodium hydroxide/ ferric chloride compound coagulant can improve the simultaneous removal effect of silicon,iron and manganese with a effluent turbidity being less than 0. 71NTU,and the pH value of the effluent can also meet the requirements of wa- ter quality.The results with sodium hypochlorite as the oxidant indicate that using ferric chloride as the coagulant can effectively remove iron and manganese,but the removal efficiencies of the silicon and the effluent turbidity are poor,and that,with calcium hydroxide being the coagulant,silicon,iron and manganese can be simultaneously removed with a lower effluent turbidity,but the pH value of the effluent is too high to meet the requirements of water quality.To sum up,it is recommended to adopt the aeration oxidation +calcium hydroxide/ferric chloride compound coagulant as the simultaneous removal method of silicon，iron and manganese in the groundwater.When the calcium hydroxide dosage is 500mg/L and the ferric chloride dosage (calculated with Fe³⁺ ) is 22. 4mg/L,the residual silicon,iron and manganese contents (with an effluent turbidity being less than 0. 65NTU and a pH value being 8. 5) in the efflu- ent are 13. 74,0. 15,0. 005mg/L,respectively,which can meet the requirements of drinking water health standards.