Comparative study on bioleaching of two different types of low-grade copper tailings by mixed moderate thermophiles  

混合中度嗜热微生物浸出两种不同类型低品位铜尾矿的比较研究（英文）

作　　者：Xiao-dong HAO Xue-duan LIU Qin YANG Hong-wei LIU Hua-qun YIN Guan-zhou QIU Yi-li LIANG 郝晓东;刘学端;杨琴;刘宏伟;尹华群;邱冠周;梁伊丽(中南大学资源加工与生物工程学院,长沙410083;中南大学生物冶金教育部重点实验室,长沙410083)

机构地区：[1]School of Minerals Processing and Bioengineering,Central South University,Changsha 410083,China [2]Key Laboratory of Biometallurgy of Ministry of Education,Central South University,Changsha 410083,China

出　　处：《Transactions of Nonferrous Metals Society of China》2018年第9期1847-1853,共7页中国有色金属学报（英文版）

基　　金：Projects(31570113,41573072)supported by the National Natural Science Foundation of China

摘　　要：The bioleaching of two different types of low-grade copper tailings,acid-leaching tailings(ALT)and copper flotation tailings(CFT)by mixed moderate thermophiles,and the variation of mineralogical and microbiological characteristics during their dissolution processes were comparatively investigated.Results showed that bioleaching behaviors of the two types of tailings were significantly different.In ALT bioleaching,lower redox potential,higher[Fe3+]/[Fe2+]ratio and higher cell density in solution were obtained.These resulted in higher total copper,primary copper sulfide and secondary copper sulfide extractions,compared with CFT bioleaching.X-ray diffraction analysis suggested that gypsum and some metal organic complexes were detected in CFT bioleaching,which could cause the sluggish oxidation of sulphide minerals.The shifts of microbial community in the leachates and leaching residues varied greatly between ALT and CFT bioleaching.The percentage of iron-oxidizing bacteria in ALT bioleaching was higher than that of CFT,but the sulfur-oxidizing bacteria percentage was the opposite.The archaeon F.thermophilum L1 was detected in ALT but not in CFT.利用混合中度嗜热微生物浸出比较研究两种不同类型的低品位铜尾矿(酸浸尾矿和铜浮选尾矿)在浸出过程中矿物学和微生物学特征的变化。结果表明:两种尾矿的浸出行为具有很大的区别。与铜浮选尾矿相比,酸浸尾矿的浸出液中氧化还原电位较低,[Fe3+]/[Fe2+]的比例和微生物菌体密度较高,导致总铜、原生硫化铜和次生硫化铜的浸出率增加。XRD结果表明,在浸出浮选尾矿中,检测到石膏和金属有机复合物,这些物质会减缓硫化矿物的氧化过程。两种尾矿浸出过程的微生物群落变化明显:酸浸尾矿浸入过程中铁氧化菌的比例高于浮选尾矿浸出的,但硫氧化菌比例低于浮选尾矿浸出的,浸出酸浸尾矿时可以检测到F. thermophilum L1,但在浸出浮选尾矿中检测不到。

关 键 词：BIOLEACHING TAILINGS microbial community dynamics mineralogical analysis 

分 类 号：TF18[冶金工程—冶金物理化学]