浸矿菌的选育及对低品位钼矿的浸出试验研究

Breeding of Leaching Bacteria and Bioleaching Experiment on Low Grade Molybdenum Ore

针对有研究认为钼对细菌等微生物的生命活动具有较强的毒害和抑制作用问题,以从陕西洛南钼矿区矿坑水中分离得到自然混合菌种为对象,在驯化培养的基础上,对本矿区低品位钼矿石进行了浸钼试验。结果表明,在浸矿矿浆浓度为15 g/L、初始p H=2.0、接种量为12%、Fe2+浓度为5.5 g/L、Fe3+浓度为3.5 g/L、培养箱转速为160 r/min、浸出温度为30℃、培养时间为25 d情况下,钼的浸出率达73.57%,明显高于相应无菌化学浸出12.52%的钼浸出率。该原生混合菌群有较好浸钼效率的原因表现为2方面:其一,该原生混合菌对矿浆环境的耐受性较高;其二,该工艺过程充分激活了微生物浸矿的直接作用和间接作用过程。

Based on the studies that molybdenum has a strong toxicity and inhibitory effect on the life activities of microorganisms such as bacteria, the natural mixed strains isolated from the water of Luonan molybdenum mine in Shaanxi Province were cultivated and domesticated to leach the local low-grade molybdenum ore. The leaching conditions determined by single mineral tests were pulp concentration of 15 g/L, initial p H value of 2.0, inoculation size of 12%, Fe2＋concentration of 5.5 g/L, Fe3＋concentration of 3.5 g/L, incubator speed is 160 r/min, temperature of 30 ℃ and incubation time of 25 d. Conducted on this conditions, the molybdenum bioleaching rate of test was reached 73.57%, which was obviously higher than the molybdenum leaching rate only 12.52% in the corresponding sterile chemical leaching experiment. Reasons mainly come from two aspects by analyzing the experimental processes of the native mixed bacteria leaching low-grade molybdenum ore, one is that the native mixed bacteria are more tolerant to the pulp environment, and the other is that the process fully activates the synergistic effect of direct and indirect action of biological metallurgy.