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By Oscar F. Tangel

This paper outlines Canada's current status in world iron ore markets, and evaluates t he prospects for the future. Estimates for the production, export and consumption of iron ore are given. Canada's major market will continue to be the United States, with the European Common Market countries, Japan and the United Kingdom also forming important outlets. The advantages held by Canada's major competitors in these latter three market areas are briefly discussed

Feb 1, 1966

By João Felipe Costa, Jair Carlos Koppe, André C. Zingano

Abstract - Traditional mine planning based on block models built with interpolation techniques such as kriging does not take into account the uncertainty associated with the estimates. These models are inadequate for short-range mine planning. In contrast, conditionally simulated models reproduce the actual variability (histogram) and spatial continuity (variogram) of the attributes of interest. Conditional simulation can be used to address the problem of measuring the uncertainty associated with an estimate. This paper outlines how the sequential Gaussian conditional simulation algorithm can be used to assess uncertainty of grade estimates and also illustrates how simulated models can be incorporated into mine planning and scheduling. A case study demonstrates the efficiency of the method in assessing risk associated with geological and engineering variables.

Jan 1, 2000

By Stanley G. Butcher

Predictions of coal cleaning plant performance from the washability data are traditionally used at the conceptual design stage of a coal preparation plant to confirm process selection. The development of computer programs which simulate the operation of a plant facilitates the optimization of product yield and quality, and ultimately proceeds. It is shown that the optimum is sensitive to changes in mine operations and market price structure. A computerized review of operations is thus recommended as an on-going activity .

Jan 1, 1979

By T. R. Bieler

"Hot forming and superplasticity in powder metallurgy aluminum alloys and composites is reviewed. The effects of alloy composition, particulate composition, size, and size distribution is summarized. The role of climb distance for recovery is described in connection with the size of strengthening phases. In materials with fine strengthening phases on the order of one micron or less, high strain rate superplastic deformation processes are likely. However, the quality of superplastic deformation depends on the prior processing history, and these effects are reviewed. Very few data describing the effects of hot forming history on post-forming properties exist, but some results emerging in the literature are compared.IntroductionHot deformation in aluminum based materials is done for several technological purposes, such as thermomechanical processing to alter mechanical properties of simple forms, and/or final shaping operations to produce a complex shaped part by means of extrusion, forging, or superplastic forming. In the interest of improving the mechanical properties of aluminum based materials, two microstructural design strategies are commonly used, dispersion strengthening, and composite strengthening. The introduction of fine, stable dispersions is commonly done for high temperature strength, and the dispersions are typically ceramic particles in the range of 10 nm to 1000 nm in volume fractions around 5 vol.% (Higashi et al., 1990; 1991a; 1991b; 1992; Bieler and Mukherjee, 1990; Otsuka et al., 1987; Bieler et al., 1991; Oliver and Nix, 1982). Alternatively, composite strengthening strategies using 10-40 v% of 3 µm to 40 µm ceramic particles provide high modulus and high strength aluminum based materials (Midling and Grong, 1995; Lloyd, 1994; Subramanian et al., 1995)."

Jan 1, 1997

The hydrometallurgical treatment of copper ores and concentrates continues to be an active field of innovation. The direct extraction of copper from ores containing chalcopyrite is an important development to provide an alternative to flotation-smelting and refining. Jetti Resources (with the University of British Columbia) and the JX Nippon Group have developed process options for chalcopyrite heap leaching. Biological heap leaching developments for chalcopyrite are also continuing in parallel. These direct leaching technologies are also very attractive for arsenical ores. The atmospheric leaching of copper concentrates is an attractive option along with autoclave processing. The Galvanox™ Process is the focus of commercialization by InCoR Galvanox Holdings under exclusive license by the University of British Columbia. The Galvanox™ Process can be used to treat chalcopyrite or enargite containing concentrates to high copper extraction with simultaneous precipitation of arsenic as atmospheric scorodite. FLSmidth has continued development of the Rapid Oxidative Leach (ROL) and associated technologies for chalcopyrite leaching. The Glencore Albion Copper Process using ultra fine grinding of copper concentrates and atmospheric leaching has found application in central Africa. The pressure leaching of copper concentrates continues to be attractive for rapid, complete oxidation of sulfide minerals with high copper extraction and arsenic stabilization of iron-arsenate minerals and precipitates. The Ecometales PLCC project is designed to use high temperature total pressure oxidation for treatment of an arsenical copper concentrate with use of existing copper SX-EW facilities for copper cathode production. The excess acid from the autoclave process will be used to make up the acid demand for associated copper ore heap and dump leaching operations. INTRODUCTION The recovery of copper from ores is dominated by the flotation of copper concentrates followed by smelting—converting and electrorefining. This process has been enabled by the development of froth flotation and progressively made more efficient by advances in smelting and converting technologies.

Jan 1, 2019

By X. J. Guo, H. X. Li

The biological heap leaching at Zijin copper mine is currently the largest industrial application of biohydrometallurgy and one of the earliest mines to develop biological metallurgy technology in China. Since 2001, through demonstration plant and different expansion stages, it has been developed to produce 20,000 tons cathode copper annually. However the ore grade of heap leaching gradually decline year by year with copper grade average at around 0.23% now. The copper mineral is mainly the secondary copper sulfide, and symbiosis with higher content pyrite, the sulfur and iron contents is about 15 times as copper in the ore (S/Cu>15), so the acid and iron treatment of leachate, extractant and acid mine waste water is a great challenge. Combined with located in the rainy area of southern China, huge amounts of over 10 million cubic meters acid drainage need to be treated every year, so the recovery of copper from waste water as well as low grade ore is one of the characteristics of this process. This paper in general introduced the operation of heap leaching, solvent extraction, stripping and electrowinning process in Zijin mine, summarized the experience of production and technical practice, and discussed the methods of heap construction, leaching rate enhancement, third phase formation and treatment, mine effluent treatment, resource recovery and heap slope reclamation. INTRODUCTION The Zijinshan gold and copper mine is located in southeast China, Fujian province, and the typical distribution characteristics of gold and copper deposit are "upper gold and lower copper", both are large porphyry deposits. By the end of 2017, the accumulated proven reserves of available gold resources were 318 tons, copper are 2.15 million tons, and the prospective reserves of copper are more than 5 million tons. The gold mining is open pit while the copper mining is open pit and underground. The cut-off grade of gold mining is 0.15 g/t, and that of copper mining is 0.15%. A large number of very low-grade gold ores (grade <0.30 g/t) adopt a combined ore-dressing process of “partial crushing/ore washing/reprocessing/heap leaching (overlying)/ carbon slurry" independently developed, while flotation and bio-heap leaching are adopted for copper mine. Among them, copper ore with more than 0.25% copper content enters the flotation system to produce copper concentrate, while that of less than 0.25% copper content is processed by bio-heap leaching, solvent extraction and electrowinning. Zijin biological heap leaching plant is the first mine in China to achieve the scale of annual output of ten thousand tons of cathode copper since 2006. In 2008, the solvent extraction and electrowinning system were expanded, now with a daily processing capacity of 20,000 tons of ores, an annual output of 20,000 tons of cathode copper, the expanded plant is the largest biohydrometallurgy plant in China.

Jan 1, 2019

By T. Bhambhani, O. Yavuzkan, D. R. Nagaraj

"Cu ore bodies commonly contain oxide Cu at the surface, with sulfide Cu content increasing with depth. The recovery of oxide Cu minerals by flotation is a longstanding challenge in the minerals industry, especially for high acid-consuming ores which would not be economical for direct acid leaching. Current practice of oxide Cu recovery involves sulfidization (often using controlled potential sulfidization or CPS) using NaSH (or Na2S) followed by flotation using traditional sulfide collectors. CPS has shown to improve recovery of oxide Cu but has the following limitations: a) HSE issues with NaSH, b) high consumption of NaSH, and c) inability to recover certain oxide Cu minerals because they are refractory to sulfidization. The oxide Cu flotation is further complicated by the presence of certain non-sulfide gangue minerals which adversely impact both recovery and selectivity.Over the past eight decades, numerous collectors have been proposed and evaluated for the direct flotation (i.e. without sulfidization) of oxide Cu minerals, the most researched of which is alkyl hydroxamate. While there are numerous publications dealing with the fundamentals of interaction of alkyl hydroxamates with single minerals, there are few publications which discuss the practical aspects of alkyl hydroxamate use in ore flotation, particularly their use with sulfidizing agents. Case studies in this paper include methods to identify optimum combinations of sulfidizing agents and oxide collectors to maximize recovery for various types of ores. It was observed that some ores do not require any sulfidization, while others require at least partial sulfidization to improve efficacy of AHX. Depending upon the ore type and mineralogy, recovery improvement in the range of 5 to 15% units, over and above that achieved with CPS, has been observed with the use of AHX. For ores requiring high dosages of NaSH, it was shown that AHX can be used to reduce the NaSH consumption significantly. The challenges associated with the presence of non-sulfide gangue minerals in oxide copper ores are included, and the use of modifiers to alleviate the associated problems and enhance the performance of AHX is discussed."

Jan 1, 2016

By Jan Nemcik

Among other products steel mesh has been used successfully for many years to support strata and minimise loose material from falling into the mine opening. Installation of steel mesh has proven to be difficult to automate and many other products, such as Thin Spray-on Liners (TSL), have been proposed as a replacement. Ideally, the mechanical properties of these products should be superior to those of the steel mesh, however, most TSL trialled in mines to date have been weak and in addition have had slow cure times, as a result none of these materials can seriously compete with steel mesh. Now a new polymer product that cures in seconds and forms a stiff strata binder that surpasses the properties of steel mesh is under development at the University of Wollongong. To enable selection of a suitable polymer material for roadway skin reinforcement several numerical models were constructed to investigate the role of interface roughness and the influence of polymer stiffness on load transfer along the rock-polymer interface. Laboratory tests indicate that the shear adhesion of the rock-polymer interface can be substantial while the tensile adhesion can be much lower. The models indicate that the natural stone roughness and surface waviness plays a major role in shear adhesion while the elastic properties of polymer liner can significantly influence the polymer ability to resist fracture opening.

Oct 1, 2009

By Christian M. Bauer

Modern surface mines are among the world&apos;s largest single consumers of diesel fuel. A typical mine site can consume in excess of 200 million liters of diesel fuel per year. Delivered diesel fuel is not necessarily clean. Depending on the mode of transportation, handling practices and local climate, incoming bulk fuel can contain up to 20 mg/L suspended solid contaminants and also significant quantities of free water, which can amount to substantial quantities ? for a typical mine site 200 to 400 kg of dirt per year. Standard on-board fuel filters are not designed to handle high levels of contamination, and most engine manufacturers have specific fuel cleanliness requirements to ensure reliable engine operation. New developments in fuel injector technology, such as high pressure, common rail injectors require even cleaner fuel. In order to ensure reliable operation, it is therefore recommended to control particulate contamination throughout the entire Diesel supply chain - from the bulk storage on mine sites to the injection systems on-board through the use of particulate filtration and liquid coalescence technologies. In this work, the author introduces a comprehensive approach to contamination control for the entire fuel supply chain, and discusses the benefits of using advanced filtration and separation technologies, with a particular focus on the requirements of modern high pressure, common rail (HPCR) fuel injection systems.

Nov 1, 2011

By B. Morrison

"The Kiruna Electric System is a recently developed inclined ore haul age system for underground mining operations. Although an initial investigation was carried out at the Swedish underground iron ore mine LKAB almost three decades ago, it was not until 1981 that the resources of LKAB, ASEA and Kiruna Truck AB were combined to investigate, and subsequently develop an ""all- electric truck"" for the mining industry.It has long been appreciated, that major economical advantages could be realized by a mining operation through an extension of the cost-effective life of the existing ore hoisting system by the use of ramps to haul ore up to the main haulage level. Diesel truck s have been used and are being used for ramp haulage. Their use however, is limited due to ventilation and operating costs restraints.There are numerous instances of orebodies, located within a couple of hundred metre s of surface, or below an existing hoisting facility, being developed by ramp access while the shaft is being sunk. Development of an orebody via ramp access has many advantages to a mining operation where mechanized mining is to be practiced. These advantages are both practical and economical; generally falling within the over-all umbrella of the phrase ""cash flow"" mining.The decision to sink a shaft is a major committment by any mining company, regardless of size and financial reserves. Extensive diamond drilling, both shallow and deep must be carried out before a decision can be executed. This constitutes a major financial expenditure over an extended period of time.The decision to sink a shaft must be weighed against the reliability of geological interpretation of the deep diamond drilling results, the stability of the mineral market and potential fluctuation in ore prices and interest rates."

Jan 1, 1989

By Mario Bureau

Need for a lab assembly reaching better and consistent static anchorage capacities

May 1, 2013

By Gordon R. Peeling

The Problem Five years after the consensus of the Whitehorse Mining Initiative the industry was losing public confidence Public opinion surveys ranked mining just above the tobacco industry Project opportunities were being lost to public and political opposition Operating practices called into question by a number of tailings dam failures CBC broadcast of "The Ugly Canadian" Our social licence was being lost

May 1, 2013

By I. Kirman, B. Waters

World wide applications for nickel use will be summarized and examples of those uses given. Nickel products are critical to many important aspects of modern society. These products are just as important for modern China as they are in other parts of the world. It is argued that future pattern of nickel use in China should be expected to be very similar to that in the rest of the developed world. Total use of nickel in products in China is already very large. In 2004, it was the largest market for stainless steel (nickel containing) in the world. A survey of Chinese stainless steel applications will be presented. Current high nickel prices have revived speculation about substitution, particularly for nickel containing stainless steels. The presentation will discuss some of the complicating factors that need to be taken into account when considering substitution. These factors are as valid in modern China as they are in other developed economies. Recent substitution efforts and the reaction to them will be examined. The Nickel Institute position regarding appropriate application of the various grades of stainless steel will be discussed. Price-motivated substitution in China, and elsewhere, will occur but it is argued that the extent will probably be limited.

Jan 1, 2005

By A. Valenzuel

Arsenic is a common impurity in copper sulfide concentrates treated pyrometallurgically, which inevitably during the smelting-converting process reports in the final copper product affecting its properties, but also it is a very toxic occupational hazard. Arsenic recovery or disposal from concentrates or arsenic-containing copper smelter dusts have been practiced in the metallurgical industry for many years. It has been recovered principally as arsenic trioxide by roasting or leaching then precipitated. On the other hand, several hydrometallurgical processes have been developed and implemented in smelters to remove it from arsenicbearing dusts and stabilize it prior to disposal in the form of a solid compound, either as calcium arsenate, arsenic sulfide or ferric arsenate. This paper reviews the methods implemented for arsenic recovery worldwide and arsenic disposal in the metallurgical industry.

May 1, 2001

By M. Cimenti

Fuel cells have tremendous potential as power sources but much fundamental research is still required. One key component of the research is the experimental set-up used. In particular, the placement of the reference electrode is extremely significant in measuring the half-cell overpotential of solid oxide fuel cells, since differences in area, misalignments, and also differences in the kinetics of the working and counter electrodes can cause both scaling errors and frequency distortions of the measured impedance. The impedance of thin solid electrolyte cells of different electrode geometries has been calculated using the finite element method and the results compared to experimental values obtained for the oxygen reduction reaction on platinum.

Jan 1, 2005

By S. Theobald

Semi-finished copper and copper-alloy products are typically produced by casting, subsequent hot rolling or extruding and further cold working by rolling and drawing. The technological properties of the products depend not only on the chemical composition of the alloys but also on process parameters such as annealing conditions and degree of deformation. In each production step, measuring and control technology is an important tool for optimizing processes and ensuring constant high quality. This paper follows the product all the way from testing incoming scrap packages, chemical analysis of melts, mould level control in casting, non-destructive testing technologies in cold forming processes, controlling geometrical properties in the production process, to the final tests of technological properties. All test methods are focused on the applications and requirements of our customers, as the examples show.

Jan 1, 2007

By M. R. P. Snow

"This paper outlines geotechnical conditions that commonly exist in underground, hardrock mines and the challenges posed for ground-support steel, specifically rockbolts, used in these environments. A model is proposed whereby the in-situ stress and rock-mass classifications (based on Bieniawski’s rock mass rating) form the basis of determining the desired steel properties of the rockbolts used. Based on the ASTM F432 bolting specification, recommended minimum steel properties are defined for three ranges of in-situ stress levels, each with their own six ranges of RMR values. Heat treatment for the steel can be specified once these minimum steel properties are known.RÉSUMÉ Le présent article décrit les conditions géotechniques qui existent fréquemment dans les mines souterraines de roches dures et les défis que cela pose pour le soutien de terrain en acier, plus spécifiquement les boulons d’ancrage utilisés dans ces environnements. Un modèle est proposé dans lequel les contraintes in situ et les classifications de la masse rocheuse (selon la classification de la masse rocheuse de Bieniawski) servent de base pour la détermination des propriétés désirées pour l’acier des boulons d’ancrage utilisés. En se basant sur les spécifications de boulonnage de l’ASTM F432, les propriétés minimales recommandées pour l’acier sont définies pour trois plages de niveaux de contraintes in situ, chacune avec sa propre plage de six valeurs de classification de la masse rocheuse (RMR). Un traitement thermique pour l’acier peut être spécifié une fois que ces propriétés minimales pour l’acier sont connues."

Jan 1, 2016

By W. Wallace

The aerospace industry celebrated 100 years of powered flight in 2003, and the remarkable achievements that have occurred during the past 100 years are in no small way due to major developments in materials. Modern alloys for airframes, engines and other major sub-systems have evolved through the intelligent application of new processing concepts involving melting, casting, hot and cold working, heat treatment and more recently vapour phase processing. Alloy design has evolved in parallel to allow maximum benefits to be achieved from these processing advances. However, the pace of development seems to be slowing and future gains are likely to be made by learning how to extract major value from aerospace assets. Understanding the modes of deterioration and establishing cost effective lifetimes by holistic life cycle management seem to be the way of the future. Extending component lifetimes by repair, rejuvenation and refurbishment are all viable possibilities and they offer great opportunities for Canada, which, traditionally, has been a major user of modern aerospace materials rather than a supplier. The challenges for metallurgist, physicists and engineers will be no less than in the past and should create new business opportunities for Canada. The scenario described above will be developed by calling upon examples drawn from the author&apos;s experience.

Jan 1, 2004

By M. L. Free

Laboratory scale extraction of metals from heterogeneous materials such as copper ores is often performed using fine material to increase kinetics and reduce sample size requirements and costs. In contrast, commercial extraction is usually accomplished using much larger material sizes than are used in laboratory settings. The large size difference between laboratory testing and commercial application materials makes it difficult to use laboratory test data to accurately predict performance for commercial material. One solution adopted widely in industry is the use of large test columns. Large test columns cost considerably more to set up and run and take much longer periods of time to evaluate than laboratory scale tests with small particles. Consequently, from a cost and data collection efficiency perspective, the development of accurate scale up methods offers significant potential for saving both time and money. This paper provides details for a new approach to correct for scale-up phenomena in heterogeneous material processing.

Jan 1, 2007

By José J. Suárez

As pressure grows for commodity pricing, new mines are more difficult to develop, the stock markets demand better financial returns from mining companies, resources for the developing and operations are scarce, and developing countries in Asia, and Africa demand more metals, it is important that mining companies effect better utilization of capital to develop capital projects. In the last few years, the costs for Capital projects have been impacted by the following factors:

May 1, 2013