含砷复杂硫化镍矿低温生物浸出行为研究  

Dissolution Behavior of Arsenic-Bearing Complex Nickel Sulfide Ores at Low-Temperature by Bacteria Leaching

作　　者：刘学[1] 宋永胜[1] 温建康[1] 

机构地区：[1]北京有色金属研究总院生物冶金国家工程实验室,北京100088

出　　处：《稀有金属》2014年第6期1127-1133,共7页Chinese Journal of Rare Metals

基　　金：国家科技部高技术研究发展计划(863)项目(2012AA061502);国家科技部重点基础研究发展计划(973)项目(2010CB630906)资助

摘　　要：针对某硫化镍矿含砷、品位低、多金属矿混杂、地处寒冷地区等特点,为了保持较高的浸出率,低温驯化后浸矿细菌需要具有较常温细菌更高的氧化速率。基于热力学基本公式,推导了电位(E)与温度(T)的函数关系式,并使用HSC软件绘制15℃下Fe-As-Ni-S-H2O体系和Fe-Cu-S-H2O体系的E-p H图,对含砷复杂硫化镍矿进行了热力学分析。在综合了两个体系的E-p H图后,排列出在温度为15℃的微生物浸出体系中矿物随电位升高的溶解顺序,同时对比了不同反应物活度对矿物溶解的影响。在低温(15℃)下的微生物浸出过程中,研究矿浆浓度、细菌接种量、初始p H值对含砷复杂硫化镍矿中镍、铜、砷浸出率的影响。经过14 d的浸出,在优化的条件下,镍的浸出率可达65%以上,与此同时钴的浸出率可达70%以上,铜的浸出率大于50%。浸出过程中镍钴铜砷的溶解规律符合之前基于E-p H图的热力学分析结果,砷黄铁矿被优先浸出。经42 d的浸出,镍钴的浸出率大于70%,铜的浸出率则可以达到60%以上。As a kind of complex nickel sulfide ores,which are arsenic-bearing,and located in cold zone with low grade,the adapted bacteria used in leaching at low temperature need more excellent oxidative ability than mesophile bacteria to maintain the high extraction of nickel and cobalt. Based on thermodynamic principle,the function relation between the temperature（ T） and the potential（ E） was deduced. Besides,the influence of reactant activity on mineral dissolution was discussed,the E-p H diagrams of Fe-As-Ni-S-H2 O and Fe-Cu-S-H2 O system at 15 ℃ were drawn by HSC software and the order of mineral dissolution was given. In the process of bioleaching at low temperature（ 15 ℃）,the influences of pulp density,amount of inoculation and initial p H on the extraction of nickel,copper and arsenic were studied. After leaching in the optimized condition for 14 d,the extraction rate of cobalt was above 70%,the recovery of nickel was up to 65%,and the copper extraction attained over 50%. The results of dissolution of nickel,cobalt,copper and arsenic in bioleaching conformed to the result of analysis based on E-p H diagrams and the arsenopyrite was dissolved prior to other sulfides. After bioleaching for 42 d,the nickel and cobalt recovery achieved over 70% while that of copper exceeded 60%.

关 键 词：含砷 复杂硫化镍矿 低温 生物浸出行为 

分 类 号：TF18[冶金工程—冶金物理化学]