硫化矿细菌浸出机理及协同作用研究现状

细菌浸出作为一种经济、环保的处理技术,广泛应用于金属硫化物的金属提取和预处理过程中。为进一步理解细菌在硫化物浸出过程中的作用,详细阐述了细菌在浸出过程中的作用机理及其在矿物表面的作用机制,系统描述了金属硫化物溶解的硫代硫酸盐与多硫化合物途径。同时,还重点介绍了常见浸矿细菌的生存环境,并对不同种类浸矿细菌之间的协同作用进行了分析。     

缅甸莱比塘铜矿生物堆浸场翻堆提升浸出效果工业实践

针对缅甸莱比塘辉铜矿生物堆浸场生产,建立了完整的翻堆作业技术体系,包括作业节点判定、翻堆工艺、过程控制、效果评价等,通过机械手段将矿堆内部结构重组,改善渗滤性和浸出效果,稳定矿堆地质结构。对9个单元堆进行了翻堆作业,日均浸出速率平均增加0.86~4.09倍,浸出铜产量净增2648.38t,经济收益增加总计17739547美元,产量和经济效益均非常明显。     

动态图水印的堆统计攻击和防范

文章介绍动态图水印在JavaWiz软件和SandMark软件中的实现方法,并进行分析比较,针对在堆统计上暴露的问题,改进了SandMark的动态图水印实现方法.     

氧化亚铁硫杆菌培养的"瓶颈"问题研究与突破

综述了氧化亚铁杆菌液体培养现状及存在的主要问题。包括液体计数方法选择,除菌存在的误区;同时对液体培养基不能进行高温高压灭菌做了原因分析,并引入了切实可行的液体培养基灭菌方法。分析和阐述了固体培养"难分离,难纯化"的原因,同时对固体培养基的研究进展做了概括。     

Bioleaching of sphalerite by Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans cultured in 9K medium modified with pyrrhotite

Elective culture of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans in 9K medium modified with pyrrhotite was studied. Bioleaching of flotation concentrate of sphalerite by the selected bacteria was carried out. The results show that the microorganisms cultured by pyrrhotite are a mixture of Acidithiobacillusferrooxidans and Acidithiobacillus thiooxidans, of which the capability to oxidize ferrous to ferric irons is enhanced by the high mass ratio of Fe to S in pyrrhotite. Three pyrrhotite samples were separated into various parts with corresponding S/Fe ratios by magnetic separation and were used to culture the elective bacteria as the substrate. The association of the cultures could provide a more rapid and complete oxidation of sphalerite than that of bacteria cultivated by conventional methods.     

Zinc bioleaching from an iron concentrate using Acidithiobacillusferrooxidans strain from Hercules Mine of Coahuila, Mexico

The iron concentrate from Hercules Mine of Coahuila,Mexico,which mainly contained pyrite and pyrrhotite,was treated by the bioleaching process using native strain Acidithiobacillus ferrooxidans(A.ferrooxidans)to determime the ability of these bacteria on the leaching of zinc.The native bacteria were isolated from the iron concentrate of the mine.The bioleaching experiments were carried out in shake flasks to analyze the effects of pH values,pulp density,and the ferrous sulfate concentration on the bioleaching process.The results obtained by microbial kinetic analyses for the evaluation of some aspects of zinc leaching show that the native bacteria A.ferrooxidans,which is enriched with a 9K Silverman medium under the optimum conditions ofpH 2.0,20 g/L pulp density,and 40 g/L FeSO4,increases the zinc extraction considerably observed by monitoring duringl 5 d,i.e.,the zinc concentration has a decrease of about 95％ in the iron concentrate.     

Bioleaching of chalcocite by mixed microorganisms subjected to mutation

Mixed microorganisms with elevated activity of chalcocite-leaching were screened by mutation methods. The original microorganisms collected from acid mine drainage of different sites were mixed and then treated with mutagens NO₂⁻, diethyl sulfate (DES), UV and their combinations, respectively. Five groups of mixed microorganisms with much stronger ore-leaching ability were obtained by screening on the leaching media. Among them, group E of mixed microorganisms (treated with 1% DES for 60 min) with the best performance on chalcocite-leaching, increases the content of Cu²⁺ by 101.4% in 20 d of leaching compared with the control culture. In addition, group E is more tolerant to Cu²⁺ in media than the control without mutation treatment. Analysis for the diversity of microbial clones indicates that half of operational taxonomic units (OTUs) in group E are Acidithiobacillus ferrooxidans. These observations suggest that group E might have potentials for industrial application. Foundation item: Project(50321402) supported by the National Natural Science Foundation of China; Project(2004CB619201) supported by the Major State Basic Research and Development Program of China     

生物浸矿反应器的制作及矿浆质量分数分布特征

以自制的生物浸矿反应器为对象,以反应器内矿浆质量分数分布为评价指标,就搅拌器搅拌方式、外循环流量及曝气大小对矿浆质量分数的分布进行了研究.结果表明:当搅拌速度为1800～2000 r/min,搅拌桨离曝气器顶部2～3 cm,外部循环流量为13 L/min,曝气量为1.2 m3/h时,反应器内矿浆质量分数分布均匀.并对总矿浆质量分数为6 %、10 %、15%和20%的反应器内矿浆质量分数随反应器高度的变化进行了研究.     

铀堆浸废水中和沉渣减容与改性方法研究

在传统石灰中和处理法的基础上，提出了酸法难浸废水用“石灰石-石灰两步中和-沉渣循环”的流程进行处理。废水先与廉价的石灰石接触反应，使废水中的强酸中和并使铁、铝等金属离子在较低pH值下形成氢氧化物，再用石灰乳进一步中和到要求的pH。生成的沉淀物（沉渣）在过程中不断循环。该方法与一次石灰中和法相比，试剂费用节省1／3，沉渣生成量（以体积计）减少2／3，并且沉渣的过滤和沉降性能也有所改善。本工作还对沉渣减容与改性的机理进行了研究探讨。     

基于矿堆偏析特征的智能配矿方法的应用

该方法利用储矿堆会产生"偏析"作用这一特点,实现对磨矿过程的配矿。结合磨机的工艺指标,如功率、轴压、磨音、顽石量以及储矿堆的料位等外部因素,制定出磨机给矿块度和重板给料机启动顺序控制方案,通过.NET技术、数据库技术、MATLAB技术等混合编程实现对储矿堆的"金字塔"型控制,该方法在有效的确保选厂处理量前提下,稳定磨机内部的料位在正常值范围内,提高了磨机的磨矿效率,稳定了磨矿产品的粒度,减少了钢球和衬板的损耗。