铁闪锌矿浮选精矿的生物浸出和细胞固定化的研究
文献类型：学位论文
| 作者 | 王素婷 |
| 学位类别 | 硕士 |
| 答辩日期 | 2008-05-29 |
| 授予单位 | 中国科学院过程工程研究所 |
| 授予地点 | 过程工程研究所 |
| 导师 | 张广积 |
| 关键词 | 铁闪锌矿浮选精矿 生物浸出 氧化亚铁硫杆菌 中度嗜热铁氧化细菌 固定化 |
| 其他题名 | Studies on Bioleaching of Marmatite Flotation Concentrate and Bacteria Immobilization |
| 学位专业 | 化学工程 |
| 中文摘要 | 矿物的生物浸出是近年来发展很快的一项矿物处理技术，同传统的提取工业过程相比，具有投资少、对环境基本无污染等优点。但也存在一些不足和局限性，最主要的是浸出周期长，生产效率低。强化生物浸出技术和工艺的研究越来越受到重视，以期待生物浸出成为经济有效的有色金属提取技术之一。我国铁闪锌矿[(Zn，Fe)S]资源丰富，由于含锌低含铁高，适合采用生物浸出工艺。因此，对铁闪锌矿进行生物浸出的基础研究具有重要的现实意义。在此基础上，开展与工业化生产有关的浸出工艺研究。研究采用细胞固定化技术作为有效分离的间接细菌浸出过程的一个独立单元，提高浸出速率，改善细胞耐毒性能，缩短浸出周期。 本论文以铁闪锌矿浮选精矿为目标矿物，通过考察细菌接种量和外加亚铁量在常温菌Acidithiobacillus ferrooxidans和中度嗜热菌MLY浸出铁闪锌矿中的影响，并通过SEM和EDX等分析手段得出：由于两种细菌生长条件和氧化底物的能力不同，造成锌浸出曲线和矿浆pH变化趋势存在差异。铁闪锌矿矿浆中接种常温菌时，必须预先添加一部分亚铁作为细菌氧化生成三价铁的来源。由于硫的不完全氧化，铁闪锌矿的常温菌浸出是一个pH升高的耗酸过程；因为温度和酸度提高，在不添加亚铁时，中度嗜热菌MLY可以浸出铁闪锌矿，MLY在浸出铁闪锌矿中的作用主要是氧化溶液中的亚铁为三价铁。 对中度嗜热菌MLY和常温菌Acidithiobacillus ferrooxidans进行实验室规模的生物反应器的固定化吸附实验，考察稀释率对固定化细胞氧化亚铁的影响得出：聚氨酯泡沫材料能够较好的固定细胞，固定化细胞对亚铁的氧化速率比不固定时快，固定化细胞对Zn2+的耐受能力显著提高。 |
| 英文摘要 | Bioleaching is a mineral processing technique which has made great progress in recent years. Compared with traditional technology, it has advantages of low investment and being benign to environment. But the main disadvantage is of long leaching period which reduces the leaching efficiency. Studies on improving bioleaching technology have been paid more attention so as to make it become an effective technique for non-ferrous metals treatment. Marmatite [(Zn,Fe)S] is a rich resource of zinc ore in China, which is difficult to be processed effectively by traditional technology due to its low content of zinc and high content of iron. It is a better choice to treat the marmatite flotation concentrate using bioleaching technology. So it is of great importance to do fundamental studies on bioleaching of marmatite flotation concentrate. Based on the indirect mechanism, the IBES process (Indiect Bioleaching with Effects Separation) was developed to improve the kinetics. Cell immobilization as a separated unit was studied to accelerate the biooxidation rate of ferrous ions as well as improve bacteria tolerance of metal ions. In this study, marmatite flotation concentrate was bioleached by a mesophilic bacterial strain Acidithiobacillus ferrooxidans and a moderately thermoacidophilic iron-oxidizing bacterial strain MLY. Effects of external addition of ferrous ions and inoculum were investigated and residues were analysed by SEM and EDX. Different growth temperatures, acid environments and affinities for the Fe2+ and S0 substrates of the two bacteria led to different trends of leaching rate. For Acidithiobacillus ferrooxidans bioleaching, experimental results showed that an appropriate amount of Fe2+ ions were needed to trigger marmatite bioleaching. At the end of bioleaching, incomplete oxidation of elemental sulphur led to the pH raise. For moderate thermophilic bacteria MLY bioleaching, the IV 铁闪锌矿浮选精矿的生物浸出和细胞固定化的研究 higher temperature and acidity improved the dissolution of marmatite, thus MLY can leach marmatite without added Fe2+ ions. The main role of MLY in the bioleaching of marmatite concentrate is to oxidize Fe2+ to Fe3+. Lab-scale immobilization experiments by adsorption were carried out using MLY and Acidithiobacillus ferrooxidans, and effects of dilution on biooxidation rate of ferrous ions were studied. It was found that polyurethane is a good carrier for bacteria immobilization, the biooxidation rate of ferrous ions of immobilized cell is faster than that of free cell and immobilized bacteria have a better tolerance ability to zinc ions. |
| 语种 | 中文 |
| 公开日期 | 2013-09-13 |
| 页码 | 72 |
| 源URL | [http://ir.ipe.ac.cn/handle/122111/1207]  |
| 专题 | 过程工程研究所_研究所（批量导入） |
| 推荐引用方式 GB/T 7714 | 王素婷. 铁闪锌矿浮选精矿的生物浸出和细胞固定化的研究[D]. 过程工程研究所. 中国科学院过程工程研究所. 2008. |
入库方式： OAI收割
来源：过程工程研究所
浏览0
下载0
收藏0
其他版本
除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。