电解锰渣中氨氮的无废液脱除及稳定化研究

通过调控电解锰渣体系的含水率并辅以热风控制系统，构建半湿式非均相反应体系，研究了生石灰添加量、反应时间及锰渣含水率等因素对脱除电解锰渣中氨氮的影响。结果表明，在氨氮与生石灰(NH₄⁺/CaO)物质的量比为1∶3、含水率22.4%、反应时间260 min时，NH₄⁺-N去除率为95.6%，锰渣浸出液中NH₄⁺-N浓度为37.61 mg/L。此时添加多羟基磷酸盐作为稳定剂，当NH₄⁺/PO₄^3-物质的量比为1∶2时，经稳定化处理后的锰渣浸出液中NH₄⁺-N浓度满足污水综合排放标准(GB 8978—1996)一级标准限值(15 mg/L)。该工艺实现了电解锰渣中氨氮的零废液脱除，具有重要的工业应用价值。

Removal and Immobilization of Ammonia Nitrogen in Electrolytic Manganese Residue with Zero Discharge of Waste Water

A semi-wet heterogeneous reaction system was established by regulating the water content of electrolytic manganese residue and adopting a hot-air control system. The effects of quicklime dosage, reaction time and water content of electrolytic manganese residue on removal of ammonia nitrogen from electrolytic manganese residue were investigated. Results show that with ammonia nitrogen and quicklime (NH₄⁺/CaO) at a molar ratio of 1∶3, water content of 22.4% and reaction time of 260 min, the removal rate of NH₄⁺-N can reach 95.6% and the concentration of NH₄⁺-N in the leaching solution is 37.61 mg/L. Then, plyhydroxyl phosphate is added as an immobilizing agent. With NH₄⁺/PO₄^3- at a molar ratio of 1∶2, the concentration of NH₄⁺-N in the leaching solution after immobilization can meet the Grade I of 15 mg/L in the comprehensive sewage discharge standard (GB 8978—1996). This processing technique can remove ammonia nitrogen from electrolytic manganese residue with zero discharge of waste water, showing great potential in industrial application.