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Development of Bioreactors for Leaching of Sulfide Minerals

硫化矿物浸出生物反应器的开发

基本信息

批准号：
05555282
负责人：
ASAI Satoru
金额：
$ 6.4万
依托单位：
University of Osaka Prefecture
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research (B)
财政年份：
1993
资助国家：
日本
起止时间：
1993 至 1995
项目状态：
已结题

项目摘要

This report describes a biochemical engineering approach to the bioleaching of sulfide minerals by acidophilic sulfur-oxidizing bacteria in stirred tank reactors operated in a variety of modes.1. Rate data collected for the T.ferrooxidans-elemental sulfur system were analyzed to evaluate the microbial kinetic and stoichiometric parameters, using our kinetic model previously proposed for batch bioleaching. These key parameters for elemental sulfur were similar magnitude to those for metal sulfides such as pyrite (FeS_2) and sphalerite (ZnS). In the leaching of pyrite, moreover, the thermophile A.brierleyi had about four times the specific growth rate of the mesophile T.ferrooxidans, demonstrating that the thermophile is more effective than the mesophile for the pyrite leaching.2. The bioleaching of pyrite was observed to be greatly accelerated by adopting the repeated batch operation (partial replacement of solution) and the semi-batch operation (the solution was continuously fed into a … More nd removed from the reactor, but the pyrite particles stayd in the reactor). To predict the bioleaching kinetics in the semi-batch and repeated batch reactors, the batch model was modified to take into account the removal of free cells from the reactor. The model predictions were consistent with the observed bioleaching rates.3. When the bioreactor was oberated continuously with respect to both liquid and pyrite particles, the mean leaching fraction and the free cell concentration decreased repidly with increasing the dilution rate. There was a sharp maximum in the leaching rate with respect to the dilution rate, and the leaching rate was not directly proportional to the solid-liquid loading ratio in the feed. The batch model was extended to simulate the bioleaching in a continuous flow reactor. The experimental data were predicted well by the continuous model over a wide range of dilution rates and feed solid concentrations.The above-mentioned results provide useful information concerning reasonable design and operation of stirred tank reactors for bioleaching processes of mineral resources. Less

本报告描述了一个生物化学工程的方法来生物浸出硫化物矿物的嗜酸硫氧化细菌在搅拌槽反应器中以各种模式操作。速率数据收集的T.氧化亚铁硫杆菌元素硫系统进行了分析，以评估微生物动力学和化学计量参数，使用我们以前提出的间歇生物浸出的动力学模型。元素硫的这些关键参数与黄铁矿（FeS_2）和闪锌矿（ZnS）等金属硫化物的关键参数的量级相似。在黄铁矿的浸出过程中，嗜热菌A.brierleyi的比生长速率约为嗜温菌T.ferrooxidans的4倍，表明嗜热菌比嗜温菌对黄铁矿的浸出更有效.采用重复间歇操作（部分置换溶液）和半间歇操作（溶液连续进料至反应器）可大大加快黄铁矿的生物浸出。 ...更多信息并从反应器中除去，但黄铁矿颗粒留在反应器中）。为了预测半间歇和重复间歇反应器中的生物浸出动力学，对间歇模型进行了修改以考虑从反应器中去除游离细胞。模型预测结果与实测浸出率一致.当生物反应器连续观察时，无论是液体还是黄铁矿颗粒，平均浸出分数和游离细胞浓度随着稀释率的增加而迅速下降。浸出率相对于稀释率有一个急剧的最大值，并且浸出率与进料中的固液负载比不成正比。将间歇模型扩展到连续流反应器中模拟生物浸出过程。连续模型在较宽的稀释率和进料浓度范围内对实验数据进行了较好的预测，上述结果为矿物资源生物浸出搅拌釜反应器的合理设计和操作提供了有用的信息。少