膜反应器结合离子交换法对镍钼矿的生物浸出

采用对钼有一定耐受性的金属硫叶菌,通过膜反应器结合离子交换吸附,除去钼以实现镍钼矿的浸出。研究结果表明:由于膜生物反应器(MBR)中膜的超滤作用,浸出液中的钼质量浓度保持在该菌可以承受的范围内,再通过离子交换将滤出液中的钼交换吸附,交换处理的浸出液返回浸出反应器,从而使MBR中钼保持很低的质量浓度而实现细菌对矿物高效浸出。浸出条件为:温度为65℃,接种量为10%,矿浆质量浓度为100 g/L,浸出时间20 d。在浸出过程中,当所超滤和离子交换的浸出液体积为35%左右时,MBR的Ni和Mo的浸出率分别为70.70%和46.92%;当所超滤和离子交换的浸出液体积为18%左右时,MBR的Ni和Mo的浸出率分别为74.71%和50.97%;当所超滤和离子交换的浸出液体积为10%左右时,MBR的Ni和Mo的浸出率分别为79.53%和56.52%;而在相同条件下,柱浸镍和钼的浸出率则保持在75.59%和54.07%左右;可见,在浸出液的超滤和离子交换量较低(约10%)时,MBR中Ni和Mo浸出率比同条件下的柱浸浸出率高,达到了较好的浸出效果。

Bioleaching of nickel-molybdenum sulfide ores by reactor with membrane combined ion-exchange

The bioleaching of nickel-molybdenum sulfide ores with the Mo-resistant thermophilic bacterium sulfolobus metallics in a membrance biological reactor(MBR) with ion exchange was studied.The results show that the mass concentration of Mo can be controlled with filter of the membrane and the action of ion exchange.The toxicity of Mo to microorganism decreases and maintains at a low level in the bioleaching process.When the leaching solution is filtered at the 35%,18% and 10%,the leaching percentage of Ni and Mo is respectively 70.70% and 46.92%,74.71% and 50.97%,79.53% and 56.52% after 20 d bioleaching in MBR at the condition of 65 ℃,10% of inoculation and 100 g/L of ore pulp density.While 75.59% Ni and 54.07% Mo are leached out in column under the same condition.The leaching ratio of Ni and Mo of MBR exceeds that of the column leaching when the 10% of leaching solution is filtered and ion-exchanged.