【作者】 曾冬明；

【导师】 林建强；

【作者基本信息】 山东大学 ， 微生物学， 2006， 硕士

【摘要】 利用微生物进行金属矿石的浸出具有悠久的历史，在现代化工业生产中也开始得到应用。微生物浸矿具有成本低、金属回收率高及环境友好等特点，已在工业上用来从废石、低品位原料中回收铜和铀，也适用于高品位的硫化矿与精矿，在金的提取方面有很好的应用前景，此外，还可以用于煤的脱硫等。在硫化矿细菌浸出过程中，金属的溶解速率与细菌的生物量有关，故在生物浸出过程中，微生物的生长往往是速率控制步骤。因此，构建性能良好的生物反应器并研究微生物在反应器中的生长特性，优化微生物培养条件，对提高浸出速率有着重要意义。 能够进行生物浸矿的微生物主要是一些在酸性环境中生长的铁或硫氧化细菌。近些年来对连续反应浸矿系统的微生物学种群研究结果显示，一些最适生长温度为40-45℃的中度嗜热嗜酸细菌，如喜温硫杆菌(Thiobacillus caldus)、氧化亚铁钩端螺旋菌(Leptospirillum ferrooxidans)等为浸矿细菌中的优势菌群。这一研究表明，中度嗜热的铁或硫氧化细菌在浸矿过程中具有重要的作用。喜温硫杆菌是一类专性自养硫氧化细菌，短杆状，革兰氏阴性菌，有鞭毛，可运动。 本文首先在摇床水平上，实验研究了喜温硫杆菌的培养条件，并对培养温度、pH、硫粉浓度等因素进行了优化。使用Starky-S~0无机盐培养基，最佳培养温度为40-45℃，起始pH2.5，硫粉浓度为2.0g／100mL。 在难处理金精矿等高品位硫化矿生物氧化浸出的工业应用中，高效生物反应器的构建是提高生产效率的关键。目前应用于工业上的生物反应器，普遍存在剪切力大、细胞磨损严重、矿浆浓度较低造成设备的单位处理能力较低等缺点，本文基于生物浸出体系的物系特性，构建了一套新型气体环流式生物反应器，借助于I-7000系列远程数据采集与监控模块并结合使用LabVIEW语言开发的监控程序，构建了一套在线监控系统，实验表明该系统运行良好，实现了计算机对喜温硫杆菌以及与氧化亚铁钩端螺旋茵在气升式反应器中的生长与混合浸矿的在线监测与控制。 本文对构建的反应器的混合时间、气含率、气液体积氧传递系数等主要液体力学更多还原

【Abstract】 There is a long history for bioleaching of metals using microorganisms and it has applied in modern industry. Bioleaching has many advantages, such as low cost, high recovery of metals, little environment pollution and so on. It has been used to recover copper and uranium from wastes and low-grade ores. It is also suitable for high-grade sulfide ores and refined ores, and has a bright future in extraction of gold. In addition, it is also used for desulfurization of coal. The deliquescent rate of metal is correlated with the biomass of bacterium during bioleaching process of sulfide ores. So, microbial growth is generally a limiting step in the bioleaching process. Therefore, designing efficient bioreactor, studying the characteristics of microbial growth and optimizing cultivation conditions are important for improving the rate of bioleaching.The microorganisms used for bioleaching are mainly iron-oxidizing or sulfur-oxidizing bacteria which live in acid condition. The studies on microorganism species in the continuous bioleaching system indicates that some moderately thermophilic acidophilic bacteria whose optimum temperature is about 40~45, such as Thiobacillus caldus and Leptospirillum ferrooxidans, are the dominant species. The study indicates that moderate thermophilic acidophilic iron-oxidizing or sulfur-oxidizing bacteria play important roles in bioleaching process. Thiobacillus caldus is obligate autotrophy sulfur-oxidizing bacterium, rod-shaped, motile, flagellate, Gram-negative.In this research, the cultivation conditions of Thiobacillus caldus were studied in flask bottles and the major factors including culture temperature, pH and sulfur concentration were optimized. The optimal cultural conditions with Starky-S~0 medium are at 40-45℃, initial pH 2.5 and sulfur concentration 2.0 g/100mL.In the industrial application of bioleaching of unmanageable high-grade ores, such as gold refined ores, designing a high-efficient bioreactor is pivotal for improving efficiency. At present, the widely used bioreactor in industry is stired tank, which has the biggist disadvantage for its great shear strength that can damage the cells seriously. For this reason, the pulp concentration can bot be raised high, and it lowers down the working efficiency of the equipment.With regard to the shortcoming of the stired tank bioreactor, a novel airlift reactor will be developed in order to decrease the shear force and the cell damage, and increase the更多还原