IMPROVEMENT OF BIOLEACHING EFFICIENCY BY THE GAS PHASE CONTROL

通过气相控制提高生物浸出效率

基本信息

批准号：
09555316
负责人：
INOUE Chihiro
金额：
$ 7.94万
依托单位：
TOHOKU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1999
项目状态：
已结题

项目摘要

In this study, it was examined that ratio of gas composition supplied reaction chambers was controlled in order to improve the efficiency of the bioleaching. First, the effect of ratio of concentration of gas composition on ferrous ion oxidizing activity of Thiobacillus ferrooxidans was examined. Ferrous ion oxidizing activity was most improved at 7% of carbon dioxide concentration and 5〜10% of oxygen concentration. Bioleaching with Leptospirillum ferrooxidans was carried out, using the pyrite as a model sulfide mineral. It was possible that the pyrite almost perfectly dissolved, while the generation of the sulfuric acid in the leaching was suppressed. Bioleaching experiments on the copper concentrate including poor solubility copper minerals such as enargite and chalcopyrite were also carried out. When the concentrate was not treated with silver ion, only pyrite was dissolved and copper minerals were not almost dissolved. When the bio leaching was carried out, after this concentrate was treated with silver ion, the dissolution of copper minerals was promoted and the dissolution of the pyrite was suppressed. It was proven that both of substitution reaction in mineral surface by silver ion and oxidation reaction by ferric ion were necessary to promote the dissolution of these copper minerals. Since Thiobacillus ferrooxidans and/or Leptospirillum ferrooxidans rapidly reproduces the ferrous ion produced by the mineral dissolution with ferric ion, the control of the gas composition is important in order to promote this regeneration reaction. Though in the conventional pyrometallurgy method, the processing of the copper concentrate including arsenic minerals was difficult, the handling in the real operation becomes possible by bioleaching method developed this time.

在这项研究中，检查了气体成分的比率受到的反应室的控制，以提高生物可能的效率。首先，检查了气体成分浓度比硫哥替氏硫昔氏菌的氧化活性之比的影响。在7％的二氧化碳浓度和5-10％的氧气浓度下，亚铁离子氧化活性最大。使用黄铁矿作为硫化物矿物质进行生物渗以使用瘦螺螺的铁氧分子。黄铁矿几乎可以完全溶解，而在离开中硫酸的产生被抑制了。还进行了铜浓度的生物渗透实验，包括溶解度较差的铜矿物质，例如增强和辣椒岩。当不用银离子处理浓度时，仅溶解黄铁矿，并且几乎不会溶解铜矿物质。当进行生物浸出时，在用银离子处理该浓度后，促进了铜矿物质的溶解，并抑制了黄铁矿的溶解。事实证明，必须通过银离子在矿物表面进行替代反应，而铁离子必须通过铁离子氧化反应来促进这些铜矿物的溶解。由于硫代基曲霉和/或钩端螺母铁氧体迅速再现由矿物质溶解产生的亚铁离子，因此对气体组成的控制对于促进这种再生反应非常重要。尽管在常规的高温铝法中，很难处理包括砷矿物在内的铜浓度，但通过这次开发的生物攻击方法，实际操作中的处理可能是可能的。