水洗联合固化处理电解锰渣

Treatment of electrolytic manganese slag by water washing combined curing method

为减少电解锰渣中主要污染物锰离子和氨氮含量,降低其对环境的污染,采用水洗联合固化法处理电解锰渣,通过改变水渣比、洗涤次数、搅拌时间,固化剂添加比例,观察锰渣水洗及固化过程中锰离子、氨氮的质量浓度变化并确定最佳水洗固化条件。研究表明,水渣比为2,洗涤2次,搅拌时间30 min为最佳水洗条件,此时锰渣浸出液Mn2+、NH_(3)-N的质量浓度分别为106.65和40.05 mg·L^(-1);向水洗后锰渣中添加0.15%的Na3PO4、1.00%的生石灰,0.75%的水泥和0.50%的粉煤灰为最佳固化剂添加比例,此时锰渣浸出液Mn2+、NH_(3)-N的质量浓度分别为0.141和1.260μg·L^(-1),满足污水综合排放标准。本研究结果表明,对水洗后的锰渣进行固化处理,可以有效降低浸出液中Mn2+和NH_(3)-N质量浓度,可为锰渣无害化处理提供参考。

To reduce the content of manganese ions and ammonia nitrogen,which are the main pollutants in the electrolytic manganese slag,and reduce its pollution to the environment,the combined washing and curing method was used to treat the electrolytic manganese slag,and the changes of manganese ions and ammonia nitrogen concentrations during the washing and curing process were observed and the optimal washing and curing conditions were determined by changing the water-slag ratio,washing times,stirring time and the addition ratio of curing agent.The study showed that the water-slag ratio of 2,washing twice and stirring time of 30 min were the best washing conditions,and the concentrations of Mn2+and NH_(3)-N in the leachate of manganese slag were 106.65 mg·L^(-1)and 40.05 mg·L^(-1),respectively;0.15%of Na3PO4,1.00%of quicklime,0.75%of cement and 0.50%of fly ash were added to the washed manganese slag.At this time,the concentrations of Mn2+and NH_(3)-N in manganese slag leachate were 0.141μg·L^(-1)and 1.260μg·L^(-1),respectively,which satisfied the comprehensive effluent discharge standard.The results of this study showed that the curing treatment of manganese slag after water washing could effectively reduce the concentrations of Mn2+and NH_(3)-N in the leachate,and provide a reference for the harmless treatment of manganese slag.