难处理低品位铜钴矿的微生物浸出

Bioleaching of refractory low grade copper-cobalt ore

以赞比亚某典型难处理低品位氧化铜钴矿为研究对象,配入适量硫化铜钴矿,采用人工调配的高效微生物浸矿菌群对铜钴矿进行微生物浸出,同时分别与摇瓶酸浸、搅拌酸浸和柱浸进行了对比.结果表明,采用微生物浸出难处理铜钴矿,随着温度升高和时间延长,铜浸出率增大.浸出温度为40℃时,微生物浸出铜浸出率为90.7%,高于摇瓶酸浸和搅拌酸浸浸出结束时浸出率（69.4%-73.2%）以及柱浸结束时浸出率（约85%）.由于微生物浸出群落对该难处理铜钴矿作用时间周期较长,适用于堆浸生产.细菌的存在使得铁离子不断的在二价与三价间循环,通过具有强氧化性的Fe3＋与硫化矿物相互作用,使得矿物分解,提高浸出率.

A typical refractory lowgrade copper- cobalt ore from Z ambia added a proper amount of sulfurized copper- cobalt ore was bioleached with a bacteria group of an artificial microbial leaching bacteria. The specimens were compared with sharked,stirred and column leached ones by acid. The results showed that the leaching efficiency of copper increases with temperature and time. The end leaching efficiency of copper is 90. 7% with bioleaching method at 40 ℃,which is higher than that（ 69. 4% - 73. 2%） with sulfuric acid leaching method and that（ about 85%） with column leaching. Owing to the longer operation time,it is suggested that a heap leaching process is favorable for the bioleaching method in an industrial practice. Bacteria make the Fe ions circulate between bivalent and trivalent ions.The authors believe that a strong oxidant Fe3 ＋can promote the ore decomposition and increase the leaching rate.