用浸出工艺回收酸性矿山废水沉淀渣中金属元素

摘要

酸性矿山废水沉淀渣的处置一直是废水处理工程面临的难题。以广东省大宝山矿槽对坑尾矿库外排废水处理厂产生的沉淀渣为例,开展沉淀渣中有价金属元素酸浸与回收试验。淀渣铁、锰、铜、锌、镍、铅品位分别为40919．6,14320．6,4681．4,7557．4,149．3,360．9 g/t,杂质成分主要为石英、方解石。在硫酸浓度为20%、固液比为0．33 g/mL、浸出时间为8 h、浸出温度为30℃条件下,铜、锌、镍、铅、锰和铁的浸出率分别为99．49%、21．41%、51．21%、4．45%、55．86%、34．25%。采用硫酸浸出工艺回收沉淀渣中有价金属元素在技术经济上可行,同时可缓解废水处理厂的环保压力。%The disposition of Acid Mine Drainage ( AMD) sludge has become a serious problem in wastewater treatment industry for a long period. An AMD sludge sample was taken from the wastewater treatment plant of the Duikeng tailings reser-voir,Dabaoshan Mine,Guangdong Province,and an experiment was conducted to recover valuable metals from the sludge by sulfuric acid leaching method. There is 40 919. 6 g/t Fe,14 320. 6 g/t Mn,4 681. 4 g/t Cu,7 557. 4 g/t Zn,149. 3 g/t Ni, 360. 9 g/t Pb,the impurity components are mainly quartz,calcite. In sulfuric acid concentration is 20%,solid-liquid ratio is 0. 33 g/mL,the leaching time of 8 h,leaching temperature 30 ℃,the copper,zinc,nickel,lead,manganese and iron leaching rate were 99. 49%,21. 41%,51. 21%,4. 45%,55. 86% and 34. 25%. Using sulfuric acid leaching process recycling valuable metals element in precipitation slag economically feasible in technology,at the same time,the pressure of the wastewater treat-ment plant of environmental protection was alleviated.