Thermophilic heap leaching of a chalcopyrite concentrate

Thermophiles have been shown to be the only micro-organisms to leach chalcopyrite successfully. Heap leaching may be a feasible alternative to conventional bio-reactors, providing a high temperature environment can be maintained within the heap without external heating.In the present study thermophilic heap leaching of a chalcopyrite concentrate coated onto inert support rocks (the GEOCOAT™ process) was studied in sets of small heated columns. The temperature was gradually increased to 70 °C, while successively introducing various mesophile and thermophile cultures. Individual columns were dismantled after progressively longer leach periods and the residual concentrates analysed. Copper extractions in excess of 90% were achieved within 100 days.On the basis of head and residue analyses the rate of reaction heat generated was calculated. A comprehensive heap heat conservation model was used to determine whether the experimental temperatures can be achieved and maintained in a full scale heap. Results indicate that operating hot heaps successfully is possible within a certain range of process parameters.     

惯性圆锥破碎机在铀堆浸矿山的应用研究

惯性圆锥破碎机是一种具有独特原理和结构的新型节能细破碎设备,能实现物料的选择性破碎。该机不仅破碎比大,还能将产品粒度控制在很窄粒级范围,使所需要的粒级段的产率最高,而且单位破碎比功耗低,适合于采用堆浸工艺的铀矿石破碎。简述惯性圆锥破碎机的结构特点,介绍该机在铀矿山的应用情况,表明惯性圆锥破碎机在铀矿冶行业具有良好应用前景。     

某铀矿石细菌堆浸可行性研究

对某铀矿石进行了细菌柱浸可行性研究.确定了酸度、喷淋强度、喷停时间比的最佳条件,考察浸出过程中浸出液电位、p(Fe)、P(U)的变化情况.通过与酸柱浸的比较,表明细菌浸出有助于缩短浸出周期,并使铀浸出率提高9．7％.     

堆浸厂浸出液输送系统设备选型及计算方法

主要介绍堆浸厂浸出液输送系统设备选型及计算方法,先选取一系列规格的管道,分别计算出泵的参数,并且验算管道耐压等级,然后分别计算出设备费及操作动力费,最后确定最佳管径和泵的型号。     

某铀矿石酸法堆浸试验研究

根据甘肃某铀矿床矿石特性,在小型试验基础上,对该矿石进行堆浸扩大试验,确定该铀矿石堆浸适宜的工艺条件。试验结果表明,矿石粒度为-10mm、软锰矿用量为矿石质量的3%、酸用量为4.5%时,柱浸渣中铀的质量分数均在0.01%以下,渣计浸出率可达到84%以上,该铀矿石适合于堆浸生产。     

Gold heap leaching in the permafrost zone of Transbaikalia

The article discusses constraints of the gold heap leaching technology in the conditions of permafrost in Transbaikalia and outlines prospects for the heap leaching at small placers and gold production-generated waste dumps. The authors offer innovative processes to include into gold heap leaching plants to make them higher effective and all year round operative in the severe climatic conditions.     

GeoStudio软件Slope-W模块在堆浸场边坡稳定性分析中的应用

堆浸场边坡稳定性对于矿山堆浸场的经济性和安全环保性方面具有重要意义。基于极限平衡条分法原理开发的Geo Studio软件,其中的Slope-W模块作为一种岩土结构稳定性分析通用软件,能通过建立有限元模型,施加荷载和边界条件,有效模拟土条受力以及土条间作用力,建立力平衡和力矩平衡方程,求解堆浸场最危险滑弧以及最小安全系数,从而全面掌握堆浸场边坡抗滑稳定性。本文通过该软件在工程实例中的应用,为今后堆浸场的稳定性安全设计和评价提供了一定的参考依据。     

Dynamic microbial populations in heap leaching of zinc sulphide ore

Polymerase chain reaction (PCR) technology was used to monitor the microbial population within two 6-m-high sulphide ore heaps where zinc was bioleached. Genomic DNA was isolated from microorganisms attached to the ore particles. The microbial population varied in diversity at different heap heights and at different stages of the leaching cycle. Nine bioleaching microorganisms were identified, including iron oxidizers, sulphur oxidizers, whether mesophiles, or moderate thermophiles. No bioleaching extreme thermophiles were detected. Moderate thermophiles were present at average heap temperatures of 40 °C or higher. No moderate thermophiles were present in the top 2 m of the heaps. Mesophiles were present throughout the lifetime of the heaps and at all heap depths. Cultures of Acidithiobacilluscaldus and Sulfobacillusthermosulfidooxidans originally introduced to inoculate the heaps did not proliferate but were instead displaced by other species; no benefits were obtained from heap inoculation. The most predominant species were Acidithiobacillus thiooxidans and Acidithiobacillus albertensis. Leptospirillum sp. was not predominant in the heaps, in contrast to the dominant role this organism plays in tank bioleaching operations.     

铀矿堆浸工艺中助渗剂应用的研究

在某些铀矿堆浸工艺中,由于矿石的泥化、膨胀和细颗粒迁移等原因,经常出现通道堵塞、渗透率低的问题,为此,提出了添加助渗剂的方案。助渗剂以表面活性剂为主体,目的是提高溶浸剂的渗透性和浸出工艺的效率。经对多种硬岩矿和泥矿的试验,证明其效果明显。还对助渗剂的作用机理作了初步探讨。     

The effect of particle porosity on liquid holdup in heap leaching

The inter- and intra-particle porosities of heaps have two distinct length scales (of order millimetres between the particles versus tens of microns within the particles) and therefore the dominant flow mechanisms within and around the particles are quite different. This paper investigates the effect of particle porosity on heap hydrodynamics by comparing the behaviour of a model system consisting of non-porous glass beads with a system of actual ore particles. The overall liquid holdup behaviour of these two systems initially appears quite different. However, when the effect of the liquid holdup around the particles is separated from that within the particles, the same theoretical flow model can be applied to both the model and ore systems. This demonstrates that correlating the liquid flow to the overall liquid holdup is problematic and that the effect of the inter- and intra-particle liquid holdup should be considered separately. This is important as the amount of liquid held within the ore particles in these experiments was nearly as large as that held around the particles. The model for the external liquid flow proposes a power law relationship between the relative flow rate (flow rate divided by residual holdup) and the excess relative holdup (the steady state liquid holdup divided by the residual holdup minus one) with an exponent of two. It was found that the pre-factor in this relationship was quite a strong function of particle size for the spherical glass beads, but relatively constant for the more angular ore particles.     

Discrete element method simulation of bed comminution

This paper evaluates fragmentation behaviour, particle size distribution and liberation degree during bed comminution of particles. Three different cases of bed comminution are modelled through discrete element simulations. The role of stressing velocities on breakage, effects of crushing walls on fragmentation and influence of crushing gaps on liberation and particle size distribution are considered. The discrete element sample is modelled to represent the concrete specimens of B35 strength category.It has been observed that the particles around the stressing walls fail differently than the inner particles during bed comminution. The stressing velocity and the crushing walls have been found to affect the cracking mechanism of the particles. The liberation degree in bed comminution is less as compared to single particle crushing. The results presented in this paper can be used to model the liberation and recycling of valuable aggregates from cheaper matrixes.     

蓝田铀矿某矿床碱法堆浸工业性试验

铀矿碱法堆浸工业试验在我国尚属首次。介绍了蓝田铀矿某铀矿床一年多碱法堆浸工业试验的结果。在用高锰酸钾为氧化剂的条件下,经过150 d,铀浸出率可达到72%;还详细阐述了吸附尾液闭路循环,减轻树脂中毒等成功经验。     

某难处理铀矿石强化堆浸工艺研究

针对某难处理铀矿石开展了搅拌浸出试验和强化柱浸试验,开发出了浸出中前期酸法大流量喷淋-后期高浓度硫酸熟化的强化堆浸工艺.经工业堆浸试验验证,强化堆浸工艺可使硫酸消耗(与矿石质量比)由搅拌浸出的25％降至18％～19％,浸渣铀品位降至0.012％.这种强化堆浸工艺为某难处理铀矿石的工业生产提供了技术依据.     

原地爆破浸出工艺待浸矿堆块度的分形特征研究

利用分形理论探讨研究了原地爆破浸出工艺待浸矿堆块度的分形特征，并对影响块度分维的主要因素进行了灰色关联分析。     

处理地(堆)浸铀浸出液离子交换装置类型的选择

地(堆)浸浸出液一般为清液,用离子交换法从地(堆)浸浸出液中提取铀,其装置均属于适宜处理清液中铀的离子交换效率高的密实床.对于同属于密实床的固定床吸附装置与密实移动床吸附塔作了简单的比较;对于多种型式的密实床解吸设备,从操作运行到其适用场合等方面作了介绍和分析对比;固定床及密实移动床均适合于地(堆)浸提铀厂使用,它们各有其特点.如何具体地选择这类装置,这与工厂规模、建厂方式(整体式提铀厂还是卫星厂和中心厂的分体式)、甚至还可能与各国的使用习惯等均有关,是一个较复杂的问题.     

Validation of the efficient application of the electrochemical water processing in ore heap leaching

The article theoretically and experimentally validates the effective applicability of the electrochemically treated acid wastedump water as a leaching agent for low-grade copper-zinc ores instead of sulphuric acid solutions. The authors have found the way to intensify the Cu-Zn ore leaching by adding 20 mg/l of NaCl in the electrochemically treated wastedump water, which allows the active chlorine concentration of 1.5 g/l and accelerates dissolution of copper and zinc to product solution by a factor of 2.8–6.     

矿石形状对浸堆结构及渗流场影响机制

为了研究筑堆矿石形状对堆内结构和渗流速度场分布的影响,选取了相同级配下的球团制粒矿石与普通原矿石进行柱浸实验。利用核磁共振成像(MRI)技术非接触地获取内部饱和结构,通过图像处理与统计研究了矿石形状与孔隙分布的关系,并利用Navier-Stokes方程模拟了相同压力和入渗速度下矿石形状对渗流速度场的与优势流分布影响。结果表明,饱和状态下的内部孔隙并不都服从正态分布,制粒矿石间孔隙分布更为均衡,服从正态分布,μ=2.0mm,原矿石间孔隙分布不服从正太分布,在8.00～11.00mm间缺失,最大当量直径为11.39mm;制粒矿石间速度场分布更加均匀,孔隙间无明显优势流,原矿石间速度场分布不均衡,存在贯穿结构的优势流和较大浸出盲区,出口边界表现为流场叠加状态;提出矿石形状均匀系数K可以有效描述矿石形状对内部孔隙和渗流的影响机制,K值小,孔隙分布均衡,渗流速度场分布均衡;K值大,容易产生大孔隙,连通成为优势流的通道,致使流场分布不均衡。     

原地爆破浸出与浅孔留矿联合开采法在某铀采场的应用

介绍原地爆破浸出与浅孔留矿联合开采法在西安中核蓝天铀业有限公司某采场的方案设计(穿脉和脉外天井、布液工程、落矿方式、爆破参数和器材)及实施情况(采场落矿、布液管线预埋、顺路天井架设、原地爆破浸出等)。这种联合开采法可实现高品位矿石出窿地表堆浸、低品位矿石就地爆破落矿筑堆浸出,并使布液均匀,浸出死角少,采场铀回收率提高(接近90%)。     

南方某铀矿石堆浸酸度试验

介绍南方某铀矿低品位铀矿石堆浸工业试验,根据该矿石特性,进行不同酸度浸出剂浸出试验,得出该铀矿石堆浸的经济酸度.试验结果表明,采用浸出剂酸度控制模式后,铀浸出率提高5%,酸耗降低0.5%以上,浸铀周期缩短40 d以上,为该矿堆浸工业生产提供了技术经济指标和可靠的科学依据.