采用机械活化硫精矿吸附,氧化沉淀以及氧氧化钠沉淀处理酸性矿山废水,使废水中锌、铁、锰得到分离与回收.当酸性矿山废水pH为1.83,锌、铁和锰质量浓度分别为150,2 900和315mg/L时,在10L酸性矿山废水中加入活化硫精矿975 g,反应20 min后,锌残留质量浓度为1.33 mg/L,锌去除率达到99.08％.废水经除锌后,取10L废水,当废水pH为6.92,空气流量为500mL/min,反应时间为2.5h时,铁和锰残留质量浓度分别为97.96和290.55mg/L,铁、锰去除率分别为98.28％和18.45％.XRD分析表明:氧化沉淀渣为Fe3O4和a-FeOOH,渣中铁含量为52.73％;废水经除铁后用氢氧化钠溶液调节pH至11.01,反应时间为30min时,废水中锰残留质量浓度为1.15 mg/L,所得锰渣锰含量达到34.47％;除锰废水经硫酸调节pH为7后达GB 8978-1996排放标准.%Separation and recovery of Zn, Fe and Mn from acid mine drainage was researched by applying absorption with mechanically activated pyrite, oxidation-precipitation and sodium hydroxide neutralization. The mass concentration of residual Zn is 1.33 mg/L, and the removal rate of Zn is up to 99.08% when pH of the acid mine drainage is 1.83, the mass concentrations of Zn, total iron and Mn are 150, 2 900 and 315 mg/L, respectively, the dosage of activated pyrite is 975 g in 10 L wastewater, reaction time is 20 min. In 10 L wastewater after removing Zn, the residual Fe and Mn are 97.96 mg/L and 290.55 mg/L, respectively, and the removal rates of Fe and Mn are 98.28% and 18.45%, respectively when pH of the wastewater is 6.92, airflow is 500 mL/min, reaction time is 2.5 h. X-ray diffraction (XRD) analysis shows that the products of oxidation-precipitation are Fe3O4 and a-FeOOH, in which the content of Fe is 52.73%. Then the residual Mn is 1.15 mg/L, and the Mn content in the sediment is 34.47% when pH of the wastewater is adjusted to about 11.01 with sodium hydroxide solution, and reaction time is 30 min. The effluent quality can meet the Chinese standards of wastewater discharge (GB 8978-1996) after pH of the Mn removing wastewater is adjusted to 7 with sulfuric acid.
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