铜铅锌混合精矿的矿物学特征分析及分离效率探究

中国云南省有大量的铜铅锌多金属硫化矿资源,该类矿产资源的高效选矿分离是影响企业经济效益的主要问题之一.针对云南迪庆地区的硫化混合精矿,该混合精矿铜、铅、锌三种有价金属共存,分离难度较大,导致其产品难以销售或冶炼.本文采用化学分析、X射线衍射法和矿物解离度分析(MLA)等多种检测方法,对该混合精矿的主要元素含量、矿物组成...     

A process for separation of silica from siliceous magnesian limestones

Whereas high-grade dolomites and limestones find extensive use in the refractory and steel industries, high-silica dolomitic limestones are of little use and can cause disposal problems as mining rejects. The removal of silica and magnesia to certain specified limits can make them suitable for cement manufacture. Magnesia can be removed by a carbonation process after semi-calcination of dolomite but the removal of a large amount of silica prior to MgO separation, by the flotation process alone, is uneconomical. Here the results are presented of the investigations of hydrocyclone separation of silica from one such type of mining rejects. The results show that after grinding the feed material to suitable levels of liberation of quartz and carbonate grains, two cycles of operation in a 4′′ hydrocyclone, can recover about 45% of the limestone feed material with a lime/silica ratio adequate for cement manufacture.     

鞍钢弓长岭三矿区三种矿石类型的工艺矿物学研究

１　矿石的物质组成１－１　矿石的化学成分及矿物组成三矿区矿石的化学成分较简单,碱性系数很低,在０－０３％以下;矿石为高硅、贫铁,低ＣａＯ、ＭｇＯ、Ａｌ２Ｏ３,且有害杂质ＳＯ２、Ｐ２Ｏ５含量低于工业允许值（０－５％）的酸性矿石。随着矿石中ＦｅＯ含量的降低,ＣａＯ、ＭｇＯ、Ｋ２Ｏ含量有依次降低的趋势,Ｐ２Ｏ５及ＣＯ２也随ＦｅＯ降低而逐渐降低。矿石的矿物成分以赤铁矿、磁铁矿和石英为主,其它矿物成分很少,矿石类型不同,主要矿物含量也有差异。根据矿石的化学全分析及电子探针分析结果计算的矿石定量组成见表１。…     

Analysis and optimization of mineral processing and coal-cleaning circuits — Circuit analysis

In mineral processing and coal cleaning operations, there are two classes of unit operations used in the separation processes. The first type — crushing, grinding, pelletizing and settling — modifies the size distribution of the feed. The second type — heavy media, sizing, flotation, magnetic, electrostatic and jigging — separates the particles. In these latter unit operations, the size distribution is not changed; rather, the feed stream is split into a product and waste stream based on subtle physical and physicochemical differences between the different types of feed particles. In separation unit operations, the mathematical functions, representing the behavior of the unit operations, are easy to manipulate. Thus, a number of theorems, useful to both the plant designer, and the plant engineer, can be proven.The work presented in this paper makes the fundamental assumption of linearity as do all current plant design analysis systems. The linearity assumption states that in a separation operation, there is no particle-particle interaction effecting the probability that a particle will be selected for the product or waste stream. In other words, if one doubles or triples the feed rate to a unit operation, the fraction of particles of a given characteristic selected to appear in the product stream remains unchanged. In actuality, this assumption is not true because higher feed rates affect the behavior of separation operations. However, when designing a plant, one can calculate the feed rate to a given unit operation and then select a piece of equipment large enough to handle the computed tonnage. Thus, the designed circuit behaves linearly.     

Rapid Large Volume 3D Mineral Processing and Liberation Characterization Technique to Sub Micron Resolution

We describe a novel lab based X-ray computed tomography system based on the architecture of X-ray Microscopes (XRM) used in synchrotron radiation facilities to be adapted for mineral processing and mineral liberation analysis. As this is a tomographic technique performed with an XRM, it is non-destructive and does not require complex preparation of polished sections typical of SEM-EDS techniques (such as MLA and QEMSCAN). It complements these existing techniques by providing 3D information and mineral liberation of multi-phase particles with much larger sample volume statistics but at a fraction of the time. In several applications, the technique is superior. These include the characterization of tailing loss in precious minerals; the characterization of porosity, particle size distribution, crack and pore network analysis during comminution, heap leaching and for texture and exposure/lock class analysis for floatation.     

An irregular triangle mesh buffer analysis method for boundary representation geological object in three-dimension

Three-dimensional (3D) buffer analysis is a basic function of spatial analysis used widely in 3D Geographic Information Systems (3DGIS). Current buffer analysis methods for spatial points and curves generally function well. One exception is buffer zone of surface. Previous researchers in this field have used voxel models to overcome this limitation; however, defects with voxel model buffer analysis include redundancies, approximations, and poor visualization characteristics. In this contribution, a surface buffer analysis method is presented for the boundary representation of geological objects. Exact geometric representation is achieved via the construction of irregular triangle meshes in 3D. The results can be used for 3D structural modeling and then form the basis for spatial analysis or model-based quantitative assessment in mineral potential mapping and resource evaluation. Three comparisons between existing voxel methods and our new method, evaluating visualization, precision and redundancy, are conducted. The comparisons show that our proposed method is robust and provides a higher quality output than voxel modeling. Finally, uncertainty analysis of buffer distance in different geological objects was discussed.     

Studies on concentration and direct reduction of the Ramim iron ore

Beneficiation and direct reduction of the Ramim iron ore was studied. Feed concentrates were obtained by gravity concentration of oolites followed by wet, high-intensity magnetic separation. Poor liberation prohibits physical concentration of goethite from oolites. These concentrates were directly reduced with different reductants at varying temperatures, followed by dry magnetic separation. Quality of concentrates depends on temperature, iron content in feed, type of coal, residence time, and composition of pellets. Conditions of optimum temperature range 1250–1275°C, unmixed pellets, high iron content in feed, dense high carbon reductant, and 15 min residence time resulted in grades and recoveries better than 90%. It is shown that segregation and growth of the metallic iron nuclii must be achieved in order to get superior yields.     

A theoretical analysis and control study of open-circuit grinding

Regrinding is an essential step in many mineral processing flowsheets as a final preparatory step for mineral separation. It is normally carried out in open-circuit ball mills or rod mills. Wide fluctuations occurring in the hardness and size distribution of feed materials to regrinding mills result in a nonuniform product fineness and processing inefficiency. Using a previously developed regrinding model, this paper presents the dynamic analysis and design considerations of a control system for open-circuit grinding, using the traditional P-, PI-, and PID-control algorithms. This study shows the utility of simple analysis techniques in designing a mineral process control system with special attention given to the effect of sampling and analysis time on control system performance.     

A generalization of distribution data for characterizing the performance of float-sink coal cleaning devices

The performance of float-sink coal cleaning devices customarily is characterized by a distribution curve, in which the percent of feed reporting to clean coal is plotted against specific gravity. For a given vessel and a given feed a family of distribution curves can be obtained, each having its own specific gravity of separation.This paper presents a method for combining these distribution curves at different specific gravities of separation, for a given coal cleaning vessel and a given feed, into a single, generalized distribution curve which is independent of the specific gravity of separation. This curve can be expressed in tabular form or it can be represented mathematically by an exponential type equation, known as a Weibull function.A different generalized distribution curve will be obtained for each of several different size fractions. A method is presented for utilizing these curves with feeds which encompass a broad spectrum of sizes.The well-known concepts of error area and probable error are extended to the generalized distribution curve. It is shown that the conventional probable error, and — under certain conditions — the conventional error area, are directly proportional to the specific gravity of separation for a given vessel and a given feed size.     

The effect of hydrodynamic conditions on true flotation and entrainment in flotation of a complex sulphide ore

The separation efficiency and selectivity of flotation are directly proportional to recoveries of the mineral species in the feed due to true flotation and entrainment. In this study, effects of the hydrodynamic conditions on true flotation and entrainment were investigated by using a fractional factorial experimental design. A method previously described in the literature was applied to determine the contributions of true flotation and entrainment in flotation of a complex sulphide ore. In order to apply the method, the kinetic flotation tests were conducted under various hydrodynamic conditions defined by some physical variables. Some of these tests were conducted in the presence and absence of a collector to evaluate the self-induced floatability. The selectivity index of the mineral species for entrainment was seen to be suitable evaluation of the non-selectivity and efficiency of the entrainment. Furthermore, the results of the size-by-size analysis of the froth products indicated that the presence of the self-induced hydrophobic particles in the feed is as important as the presence of very fine particles for accurate estimation of true flotation and entrainment in flotation of a complex sulphide ore. In addition, the estimated results for entrainment in flotation of the complex sulphide ore can be misleading. Therefore, a new approach would be necessary to determine the contributions of true flotation and entrainment in flotation of a complex sulphide ore.     

Flotation of calcareous Mussorie phosphate ore

Separation of Mussorie rock phosphate (P₂O₅ = 20%) from Uttar Pradesh, India, containing pyrite, calcite and other carbonaceous impurities by flotation has been successfully attempted to upgrade the phosphate values. Based on Hallimond cell flotation results of single and synthetic mineral mixtures of calcite and apatite using oleic acid and potassium phosphate, conditions were obtained for the separation of calcite from apatite which is considered to be the most difficult step in the beneficiation of calcareous phosphates. Further studies using 250 g of the mineral (?60 +150 and ?150 mesh fractions, deslimed) in laboratory size Fagergren subaeration machine employed a stagewise flotation viz. carbonaceous materials using terpineol, pyrite using potassium-ethyl xanthate and calcite using oleic acid respectively. Separation was, however, found to be unsatisfactory in the absence of a depressant.Among starch, hydrofluosilicic acid and dipotassium hydrogen phosphate, which were tried as depressants for apatite in the final flotation stage, dipotassium hydrogen phosphate proved to be superior to others. However, the tests with the above fractions did not yield the required grade. This was possibly due to insufficient liberation of the phosphate mineral from the ore body and different experimental conditions due to scale up operations. Experiments conducted using ?200 mesh deslimed fractions has yielded an acceptable grade of 27.6% P₂O₅ with a recovery of about 60%. The results have been explained in terms of the specific adsorption characteristics of phosphate ions on apatite and the liberation size of the mineral.     

Geological modelling of mineral deposits for prediction in mining

Accurate prediction of the shape, location, size and properties of the solid rock materials to be extracted during mining is essential for reliable technical and financial planning. This is achieved through geological modelling of the three-dimensional (3D) shape and properties of the materials present in mineral deposits, and the presentation of results in a form which is accessible to mine planning engineers. In recent years the application of interactive graphics software, offering 3D database handling, modelling and visualisation, has greatly enhanced the options available for predicting the subsurface limits and characteristics of mineral deposits. A review of conventional 3D geological interpretation methods, and the model struc- tures and modelling methods used in reserve estimation and mine planning software packages, illustrates the importance of such approaches in the modern mining industry. Despite the widespread introduction and acceptance of computer hardware and software in mining applications, in recent years, there has been little fundamental change in the way in which geology is used in orebody modelling for predictive purposes. Selected areas of current research, aimed at tackling issues such as the use of orientation data, quantification of morphological differences, incorporation of geological age relationships, multi-resolution models and the application of virtual reality hardware and software, are discussed.     

三维成矿定量预测系统设计与应用实例研究

隐伏矿体三维成矿定量预测是以多元地学大数据为基础的矿产预测新技术与方法。本文基于隐伏矿体三维成矿定量预测的实际需要及相关方法步骤,采用集成二次开发的方式,设计实现了一套可在三维环境下基于大数据开展定量化成矿预测工作的软件系统。本文阐述了系统的总体架构及开发方式,并对系统中各个功能模块的设计及实现过程进行详细阐述。系统融合了当前三维成矿定量预测研究的最新方法及成果,内含数据库管理、三维地球物理正演、三维空间分析以及三维预测评价等功能模块,能够对多元地学大数据进行集成和分析预测。为了验证系统的适用性和有效性,该系统被应用于长江中下游成矿带钟姑矿田三维成矿定量预测研究,相关成果表明系统的建立不但能够深化和发展三维成矿预测理论,也为新时期基于大数据的隐伏矿体找矿勘探工作提供了新方法及有力工具。     

Three-dimensional mineral prospectivity modeling for targeting of concealed mineralization within the Zhonggu iron orefield,Ningwu Basin,China

The Zhonggu iron orefield is one of the most important iron orefields in China, and is located in the south of the Ningwu volcanic basin, within the middle and lower Yangtze metallogenic belt of eastern China. Here, we present the results of new 3D prospectivity modeling that enabled the delineation of areas prospective for exploration of concealed and deep-seated Baixiangshan-type mineralization and Yangzhuang-type mineralization within the Zhonggu orefield; both of these deposits are Kiruna-type Fe-apatite deposits but are hosted by different formations within the Ningwu Basin. The modeling approach used during this study involves 3 steps: (1) combining available geological and geophysical data to construct 3D geological models; (2) generation of 3D predictive maps from these 3D geological models using 3D spatial analysis and 3D geophysical methods; (3) combining all of the 3D predictive maps using logistic regression to create a prospectivity map. This approach integrates a large amount of available geoscientific data using 3D methods, including 3D geological modeling, 3D/2D geophysical methods, and 3D spatial analysis and data integration methods. The resulting prospectivity model clearly identifies highly prospective areas that not only include areas of known mineralization but also a number of favorable targets for future mineral exploration. The 3D prospectivity modeling approach showcased within this study provides an efficient way to identify camp-scale concealed and deep-seated exploration targets and can easily be adapted for regional- and deposit- scale targeting.     

汞的形态分析研究进展

综述了自然界、特别是人体内汞的存在形态,讨论了汞形态分析中样品的预处理、分离富集、分析方法的研究现状和进展,指出了汞形态分析所面临的问题,对矿物药的药效研究及毒性和安全性评价具有一定指导意义     

Analyse des circuits mineralurgiques par cascadographie—Caracterisation de l'alimentation et evaluation de la fonction de selection

Cascadography is a generic, laboratory, instrumentational method of separating and characterizing mixes of mineral or particle species based on subtle physical and physiochemical differences. Like gas chromatography, cascadography characterizes a sample by the temporal separation of mineral species. Using a number of identical unit operations in series, the sample feed is injected into the first unit operation at time equals zero, and samples are taken at regular intervals from the last cell product. From the n-th cell, the product becomes the feed to the (n+1)th cell. Other than as a product, no material is removed from any cell—there is no circulating load or feedback. First to appear in the product are the rapidly moving particles followed by the more slowly moving particles. For example, if there exists a number of identical particles, then the particles will appear together in the output of the system. As the number of cells in series increases, so does the resolution between batches of particles with similar properties. If the system being studied is flotation, pure mineral species as well as locked particle assays can be made of the feed and waste streams, and from this information, the flotation cell selection function can be calculated.     

基于先验信息约束的重磁电联合三维交互反演技术实践——以彭山穹隆构造为例

三维地质建模是实现深部矿产勘查突破的重要途径,其通过控矿地质体的三维建模,直观刻画控矿要素之间的空间、成因和演化关系,帮助理解成矿系统,开展深部找矿预测.当前三维建模主要采用地质资料构建,在缺少钻孔等已知资料的情况下,难于构建出可靠的三维地质模型.为了克服常规三维地质建模方法可信度低、精度差的缺点,本文将重磁电交互反演...     

Nanoscale mechanical property variations concerning mineral composition and contact of marine shale

Mechanical properties of shales are key parameters influencing hydrocarbon production – impacting borehole stability, hydraulic fracture extension and microscale variations in in situ stress. We use Ordovician shale (Sichuan Basin, China) as a type-example to characterize variations in mineral particle properties at microscale including particle morphology, form of contact and spatial distribution via mineral liberation analysis (MLA) and scanning electron microscopy (SEM). Deformation-based constitutive models are then built using finite element methods to define the impact of various architectures of fracture and mineral distributions at nanometer scale on the deformation characteristics at macroscale. Relative compositions of siliceous, calcareous and clay mineral particles are shown to be the key factors influencing brittleness. Shales with similar mineral composition show a spectrum of equivalent medium mechanical properties due to differing particle morphology and mineral heterogeneity. The predominance of small particles and/or point-point contacts are conducive to brittle failure, in general, and especially so when quartz-rich. Fracture morphology, length and extent of filling all influence shale deformability. High aspect-ratio fractures concentrate stress at fracture tips and are conducive to extension, as when part-filled by carbonate minerals. As fracture spacing increases, stress transfer between adjacent fractures weakens, stress concentrations are amplified and fracture extension is favored. The higher the fractal dimension of the fracture and heterogeneity of the host the more pervasive the fractures. Moreover, when fractures extend, their potential for intersection and interconnection contributes to a reduction in strength and the promotion of brittle failure. Thus, these results provide important theoretical insights into the role of heterogeneity on the deformability and strength of shale reservoirs with practical implications for their stimulation and in the recovery of hydrocarbons from them.     

基于成矿系统的三维定量预测研究——以四川拉拉铜矿为例

随着矿产资源预测的发展,三维矿产资源定量预测评价已经成为矿产勘查领域的热点。然而真正决定矿产预测及矿产勘查成败的核心在于:如何构建恰当的预测变量来反映成矿作用过程。本文以四川拉拉铜矿为例,通过成矿系统分析“源-运-储-保”四大要素总结了该区矿产预测的地质找矿要素。基于三维地质建模技术以及成矿信息定量提取技术,构建了区域找矿要素三维地质信息。以找矿信息量为数学模型,确定了拉拉铜矿成矿有利区划,圈定了4个找矿靶区。本次研究将矿床成矿系统分析(知识驱动)与三维定量分析(数据驱动)相结合,将成矿作用过程及关键因素(源、运、储、保等)转化为可预测的具体空间要素,并使用三维可视化技术进行三维空间重构,该方法为今后的三维定量预测工作提供了有利参考。     

基于机器学习的三维矿产定量预测——以四川拉拉铜矿为例

在大数据蓬勃发展的时代背景下,矿产资源定量预测作为地质大数据的核心部分,其综合分析挖掘多元信息的基本思路与大数据的理念不谋而合。以四川拉拉铜矿为例,开展基于机器学习的三维矿产资源定量预测。通过建立三维地质模型,提取成矿有利信息,构建研究区定量预测模型;基于"立方块预测模型"找矿方法,采用机器学习随机森林算法,计算出研究区成矿概率分布,以此圈定出5个找矿远景区。结果表明,随机森林具有更高的预测准确度与稳定性,且能够对控矿要素重要性做出定量评价。该研究成功地将机器学习应用于三维矿产定量预测,为今后的矿产资源预测评价做出了积极的探索。