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This paper details a brief history of the Australian gold industry from the 1980s gold boom to the present day, highlighting an industry characterised by innovation in plant design and junior companies prepared to "have a go", in contrast to the conservatism of many larger mining companies. Design flexibility, the innovation of new processes, the preparedness to exchange "process know how" and technology singularly differentiated the gold industry from other sectors during the 1980s to the present. The introduction of two stage crushing, semi autogenous (SAG) milling, and pebble crushing, mill innovations, carbon in pulp (CIP) and carbon in leach (CIL) and the North Kalgoorlie screen etc were all exciting changes in the industry.

Jan 1, 2011

By A. Rahimi

Refractory castables based on alumina-silicate aggregates are commonly used in casting wheel components and launders. In this research the recycling process of waste magnesia chrome bricks for production of refractory castable lining for launders and casting wheel ladles at Iranian Sarcheshmeh copper complex (I.S.C.C.) is discussed. The smelting plant of ISCC consumes 4,000 tons refractory materials and produces 2,000 tons waste refractories annually. In order to reduce the environmental pollutions and gain the economical advantages, the recycling of waste refractories proved to be a solution [1]. In ISCC, 800 tons alumina or alumina-silicate refractory castables are used for linings of anode furnace ladles and launders annually [2]. In the present work, the spent bricks from reverberatory, converter and anode furnaces were analyzed in term of microstructural changes from hot zone to the cold end to evaluate the changes in texture and chemical composition. Different formulations based on recycled magnesia chrome aggregates and various particle size distribution and cement content were tested. Economic recycled magnesia chrome refractory mixture was prepared after crushing and sizing the non-deteriorated regions of wasted bricks. After evaluation of physical and mechanical properties of samples, one ton of refractory castable was prepared and successfully installed in the casting wheel ladles.

Jan 1, 2007

By A. Cummings

This paper reports two aspects of reactivity of complex Ni-Cu sulphide ores: variations that result from stockpiling of a nickel-copper sulphide ore in the Sudbury area and its consequences on flotation behaviour, especially in terms of metal losses to scavenger tails. In relation to the first aspect, self-heating characteristics of the stockpile were carried out by monitoring the internal temperatures of the stockpile. Six heat sensors were installed with respect to external conditions in local weather during a 7-month period. Stockpile temperatures were mainly influenced by ambient temperature with some retardation effects. The maximum temperature recorded in the stockpile was 44 °C. Samples taken at the beginning and at the end of stockpiling were tested to assess variations in behaviour of the rougher-scavenger flotation. Relative to the fresh ore, nickel and copper losses in flotation of the stockpile fines were 5.0 and 3.6 %, respectively. The fresh ore yields concentrates with higher nickel grades due to differential flotation behaviour of pentlandite and pyrrhotite relative to the stockpile fines, which exhibit a truly bulk flotation behaviour at least during the first 3 stages.

Aug 1, 2013

By R. J. Chase, C. Davies

"Abstract- The Merelani graphite-tanzanite deposit is located in northeast Tanzania, 14 kilometers south of Kilirnajaro International Airport and in close proximity to the towns of Moshi and Arusha . The graphite mineralization is hosted by relatively undeformed linear Proterowic metasedimentary gneisses, several of which have been subjected to hydrothermal alteration resulting in tanzanite mineralization. Exploration work comprised detailed geological mapping coupled with pit and trench channel sampling and a subsequent 1500 meters of diamond drilling. In addition, metallurgical tests have shown the graphite to be of unusually coarse flake size, crystallinity and high purity.Feasibility studies have shown the economic viability of a major coarse flake graphite deposit with the measured resource to 50 meters in excess of 9 million tonnes assaying over 8o/o graphitic carbon . Production is due to start by the end of the first quarter of 1994 with the processing plant design capacity initially set at 15 000 tonnes per annum.ln addition to graphite production, tanzanite will be produced through selective mining within the graphite open pit in the upper horizon and from underground workings within the lower horizon.The Merelani graphite-tanzanite deposit will be the first major orebody to be exploited through means of private funding since Tanzania gained independence."

Jan 1, 1994

By A. G. Matyas

Process improvements which have reduced the lead content of slag from the Brunswick lead blast furnace are described. Microscope examination and electron microprobe analyses, supported by the results of slag settling and viscosity tests, showed that typically about 70% of the lead in the lead blast-furnace slag was present in the form of entrained prills of metallic lead. The total lead content was found to increase with the magnetic susceptibility of the slag. Measurements in the furnace settler indicated the presence of a magnetite-rich layer between bullion and slag, arising from high magnetite levels in the slag. This layer was believed to inhibit the settling of entrained lead from the slag. Tracer tests showed that the average slag residence time in the settler was less than 2 minutes. Improvements in coke quality and sizing, which led to a reduction in the slag magnetite content, and the installation of a larger settler and a continuous Roy tapper, have all contributed to a significant decrease in the slag lead content.

Jan 1, 1977

By K. Eklund, T. Ahokainen

The Flash Smelting process is the most used production method for primary copper in the world. The basic idea of the Flash Smelting is to utilize the thermal value of sulfidic concentrates and melt the reaction product, in controlled conditions, without a need for external energy. This basic principle is utilized both in matte smelting and in Direct-to-Blister Flash Smelting Processes. In this paper, the behavior of normal (CuFeS2) concentrate of FSF-process is compared to the behavior of high grade feed material produced by Outokumpu Concentrate Upgrade Process with the aid of computational fluid dynamics (CPD) simulation using add-in subroutines developed by Outokumpu Technology. Results consist of the information concerning the behavior of the suspension, reaction efficiency and other parameters concerning the reactions of the feed material. It will be shown that, using the Upgrade Process, the throughput of copper from the Flash Furnace can be almost tripled.

Jan 1, 2007

By H. A. Khorami, T. Wong, B. Velapatino, E. Asselin, T. Donnelly, E. Bryce, R. Dixon

A copper–nickel concentration gradient alloy was designed and fabricated through a powder metallurgy (PM) process. Copper and nickel powders were mixed with different weight ratios from 0 to 100% copper in 10% increments. Each powder mixture was poured inside a cylindrical die and compacted between two punches using a hydraulic press machine at pressures up to 70 MPa, resulting in approximately 1 mm thick layers (discs) of pressed Cu–Ni powder. These 11 Cu–Ni compacted powder layers, i.e. 0–100% Cu with 10% increments, were then compressed together with pressures up to 420 MPa to form a green part. The green part was sintered in a vacuum furnace at 1000°C for 10 hours to form a solid mass (PM part) of Cu–Ni concentration gradient alloy. In the sintering process, Cu and Ni particles fused together and formed a single piece due to diffusion of the atoms across the boundaries of the particles. The diffusion of atoms also converted the stepwise concentration change into a uniform concentration gradient. INTRODUCTION Copper has numerous applications in different industrial sectors due to its superior physical, electrical, mechanical and chemical properties such as its excellent thermal and electrical conductivity, resistance to fatigue, high ductility, and resistance to corrosion. Moreover, copper and its alloys have natural antimicrobial properties. This has opened up new applications for copper–based self–disinfecting surfaces in healthcare in an effort to mitigate healthcare–associated infections (HAIs). HAIs affect millions of patients each year, leading to significant morbidity and mortality as well as financial losses to healthcare systems (World Health Organization, 2016). HAIs spread through three main routes: (a) iatrogenic in which HAIs are a direct consequence of medical encounters and/or treatment; (b) person to person where organisms are transferred between healthcare workers, patients, and visitors; and (c) environmental where transmission occurs via contaminated surfaces and equipment (e.g. doorknobs, railings, toilets/commodes, medical carts). The use of antimicrobial copper–based materials on high touch surfaces could diminish pathogen transmission via this latter rout. This has subsequently led to the development of a variety of copper–based materials for use in healthcare settings and promoted the investigation of the antimicrobial efficacy of copper–based materials.

Jan 1, 2019

By W. Holdsworth

The flotation mill of Dentonia Mines, Limited, at Greenwood, B.C., went into operation on April 20th, 1934, and by October 11th a total of 15,000 tons of ore had been treated. It is intended in this paper to describe briefly the operation and to give some of the operating data which have been gathered. The metallic minerals in the Dentonia ore are pyrite, chalcopyrite, galena, and, occasionally, native gold, and the gangue includes chloritic material, vein quartz, and calcite. Pyrite makes up about 90 per cent of the metallic content of the ore, in which it is disseminated as irregular grains and well-formed cubes. An average analysis of the ore is: gold, 0.27 oz. per ton; silver, 1.73 oz. per ton; copper, 0.12 per cent; lead, 0.31 per cent; and zinc, trace. From the mine ore-bin, situated near the portal of the tunnel at the mine, the ore is hauled by motor truck to the mill, a distance of three-quarters of a mile, and there dumped into the receiving bin, which has a capacity of fifty tons. The hauling is done during one eight-hour shift, commencing at 7 a.m. The maximum size of the ore fed to the mill-bin is ten inches. Lumps larger than this are broken by sledge hammer to pass through grizzly bars, spaced ten inches apart, installed above the bin. The ore is drawn from the bin by a 30-inch, 6-ply conveyor belt, 18 feet 6 inches long. In the near future, when the cross-cut tunnel is completed, the ore will be trammed to the receiving bin. This will effect a considerable saving in cost. At the same time, the bin will be set back several feet, so that the length of the conveyor belt may be doubled. This will make efficient ore-sorting possible, and so ensure a minimum of waste rock in the mill feed.

Jan 1, 1935

By Trang T. Tran-Valade

With continually increasing energy prices, the mining industry has been on the search for new energy optimization technologies. One area that is garnering great interest is Ventilation-On-Demand (VOD). Prior to selection and implementation of a VOD solution, it is important to fully understand the mine requirements as well as its existing infrastructure and the interaction with other automation in place at the site. With this information, a business case can be generated including a cost versus benefit comparison for various control strategies. To assist in the development of the business case, this paper will identify key areas for consideration and recommendations for an implementation plan.

May 1, 2013

By N. Erarslan, M. Serati

"This paper attempts to provide a simple analytical solution for the calculation of the stress tensor induced in a two-dimensional elastic ring of a brittle material subjected to general loading on either its internal or external curved surfaces. Airy stress functions and Michell’s expression in polar coordinates are used, and parametric studies are performed to investigate the influence of loading angle and the geometrical aspect ratio of the ring on the maximum induced tensile stress. INTRODUCTIONA proper and accurate estimation of the tensile strength of a given material is a crucial step in many engineering projects; in particular in rock cutting, since rocks are much weaker in tension than in compression or shear. Both direct and indirect laboratory techniques such as the direct uniaxial pulling test, the Brazilian indirect tensile test (also known as the split cylinder test), and the ring test have been proposed and developed to estimate rock tensile strength. Among these, the ring test, initially suggested by Ripperger and Davids (1946), has become particularly appealing for its ease of sample preparation and its unique breakage mechanism in almost a pure tensile mode. Unlike the Brazilian test in which high shear stresses developed in the vicinity of the contact could interfere with the tensile breakage of the disc specimen, a tensile failure starts away from the loading platens in a ring test (Hobbs, 1964)."

Jan 1, 2015

By T. Patching

"A GLANCE BACK AT what has happened in the past is often a useful guide to the future, although it should be used mainly to provide a sense of direction rather than a map that must be followed. As a preamble to discussing some of the questions posed by the organizing committee it may be appropriate to briefly review the distribution and careers of the graduates of our Department since the first degree in mining engineering was awarded in 1916. An attempt has been made to keep a record of the locations and careers of the Department's 540 graduates in mining and metallurgical engineering. Almost all of those who graduated before 1930 have now retired, but a very large proportion held positions as senior executives prior to retirement. A major proportion of those who graduated before 1950 are now in what might be considered senior management positions. Those who have 10 to 20 years of experience are generally in work of senior engineering responsibility or in supervisory or junior management ranks, while those who graduated in the last ten years appear to be generally in staff engineering or junior supervisory positions. This classification is admittedly imprecise because it is difficult to determine from a job description whether duties should be considered of an engineering or management nature - a distinction between the two terms is often over-emphasized. Nevertheless, the trend from technical engineering to management responsibilities with seniority and years of experience is clear in the careers that we have been able to follow."

Jan 1, 1972

By S. Setayeshgar

The identification of potential accidents on construction sites has been a major concern in the construction industry and it needs a proactive safety plan to reduce the risk of accidents. There are no efficient methods for checking if safety measures are taken properly on construction sites. Consequently, workers on site are not given enough awareness about dangerous areas. In addition, construction sites are dynamic and on-site situations are changing in terms of permanent and temporary structures and facilities. This information can be represented using Building Information Modeling (BIM). This paper proposes the integration of BIM and safety risk analysis by considering the risk levels associated with the work spaces of different construction tasks. Work spaces are generated in a BIM model according to the Work Breakdown Structure (WBS) of the project, reference objects in the BIM, and the schedule and resources of the task. Each work space is assigned to one or more tasks or functions, e.g., work spaces for specific tasks, shared spaces (paths), storage spaces, or spaces prohibited to workers. The assignment of work spaces is based on the workers, equipment and materials involved in the task. All the work spaces are associated with a specific duration according to the schedule of the project. Then risk evaluation of the construction site is applied in order to evaluate safety risks based on their severity and the degree of exposure of workers. For example, work spaces for storing hazard materials and for heavy construction equipment have higher risks than other work spaces. The results of the risk evaluation can be visualized in a 4D BIM model.

Aug 1, 2013

By J. E. Hawley

"The Aldermac copper deposit is in Beauchastel township, Abitibi county, Quebec. It lies about 11 miles west of Noranda. It has been described by Cooke, James, and Mawdsley(2) and by Bruce(3) and has been mapped in detail by W. Samuel and the late K. W. Fritzsche, former Mine Geologist, and by J . E. Gill and A. R. Byers, so that most of the particulars contained in the description that follows are largely the result of the work of others than the writer, whose connection with the deposit, in a consulting capacity, extended over the last 5 years of the life of the mine.According to A. V. Corlett, former Mine Manager, the property was staked during the early winter months of 1923 because of its location adjacent to the syenite intrusive that had been mapped by Cooke near the height-of-land in this township. An examination by Mr. Corlett in 1924 revealed mineralized zones to the north of MacKay lake, and in the vicinity of these K. W. Fritzsche, by dip needle and trenching, discovered the No. 1 and No. 2 deposits, which were both too small and too low grade for exploitation. During the winter of 1925, A. A. MacKay, with a dip needle, picked up a magnetic 'anomaly' in a drift-covered area about 600 feet to the north of previous workings. Trenching here revealed only a narrow zone of mineralization of little consequence, but, farther east, MacKay discovered a more pronounced 'anomaly' over what later drilling and underground work proved to be ore of commercial grade (No. 3 and No. 4 orebodies)."

Jan 1, 1954

By K. Mayhew, K. Murray

The CESL Copper Process was developed as a hydrometallurgical alternative to smelting and refining for copper sulphide concentrates. As the majority of such concentrates contain appreciable gold and silver values, effective recovery of these metals is essential to the economics of this technology. Unfortunately, conventional cyanide processing cannot be used on the residue from the copper process, clue to its unusual characteristics when compared with naturally occurring gold and silver ores. An abundance of elemental sulphur, as well as the presence of cyanide soluble copper, leads to the formation of both thiocyanate and copper cyanide which is detrimental to process economics clue to excessive cyanide consumption. This, however, can be reduced to acceptable levels by process innovations such as pressure cyanidation and cyanide recovery. This paper outlines the successful application of the CESL Gold Process to various gold-bearing copper concentrates from bench to demonstration scale.

Jan 1, 2011

By Jehan Rondot, Raymond Marleau

"Des quartzites trés pars ont été découverts au cours de la cartographie de la region du lac des Martres, étape de l'étude géologique de la region de Charlevoix.On distingue quatre groupes métasédimentaires, tons con tenant des niveaux de quartzite dans an mains deux domaines géologique différents, c'est à l'ouest, clans le do¬maine gneisso-charnockitique que se situent les quartzites du groupe des Martres. Quartzite et gneiss à, grenat et sillimanite, en banes épais, constituent la formation de La Galette. A Pest, dans un environnement gneisso-granitique, les deux groupes métasédimentaires de Saint-Siméon, et de La Malbaie comprennent, par contraste, des bancs pen épais et de compositions variées. Les niveaux de quartzite dépassent rarement 50 m d'épaisseur. L'autre groupe métasédimentaires, celui de Saint-Tite des Caps, recoupé de nombreuses intrusions charnockitiques et granitiques, ne possède que de minces niveaux de quartzite.La pureté et la grande épaisseur des quartzites de La Galette suppose une histoire complexe qui se termine par des depots continentaux de climat aride, par opposition aux depots marins des autres groupes. D'autre part, la presence de ces quartzites an sein de roches Presque anhy¬dres et de haute temperature que sont les charnockites leur confére des caractéristiques de fusion sans decrepitation.Parmi la multitude de depots de quartzite qui existe clans le monde, peu sont de qualité supérieure. Or, de par sa composition chimique, le quartzite de La Galette se compare avantageusement à ceux des meilleurs gisements des Etats-Unis, de l'Europe de l'Ouest et de l'Afrique du Sud. D'accès facile pour l'exploitation, les gisements ne sont qu'à une trentaine de milles de Baie Saint-Paul ou de La Malbaie, sur le Saint-Laurent.L'utilisation en metallurgic prévue pour le quartzite de La Galette comprend la production de silicium, de ferro¬silicium et d'autres alliages de silicium. La composition du quartzite est en outre appropriée pour la production de carbure de silicium et de silicate de sodium. Les fines peuvent être utilisées pour la fabrication du verre et comme matiere de charge"

Jan 1, 1977

By T. P. Weldum, W. Conger

"These studies address the relationship between mill media sizing and its grinding efficiency. Starting with the results from a review of the literature, the issues of initial media sizing for a new ball milling circuit, and then optimal media sizing for an existing milling operation, were studied. The Functional Performance parameters “Mill Grinding Efficiency” and cumulative “Mill Grinding Rates” from both plant and test-scale equipment were used, and provide valuable new insight into this topic. A plant media sizing diagnostic tool is presented, as are newly developed testing equipment and evaluation methods, and recent case studies.REVIEW OF MEDIA SIZING LITERATURE For a plant metallurgist to answer the question “How can I maximize plant profit by manipulating this grinding circuit variable?” she must know what effect the variable has on grinding circuit efficiency. Despite the significant cost of grinding media and its potential effect on production capacity, the ‘best’ media sizing remains ill-defined for any given ball mill circuit in the industry today. The underlying reasons for this will be discussed. But the importance of this issue drove Metcom and its industrial partners to take on the challenge of how to engineer the ball charge for an existing grinding circuit. In the absence of any proven method, the first step was a review of the literature. Sponsored by Cleveland-Cliffs, Inc., a broad review of the literature was undertaken, producing “The Effect of Media Sizing on Ball Milling Efficiency” (McIvor, 1997). Among hundreds of publications that were reviewed that discuss the topics of media sizing or wear, forty-five were studied in detail. These were grouped into: plant experiences; laboratory and pilot plant investigations; media wear studies; population balance modeling studies; and general papers on ball milling which included the topic of media sizing. The reader is encouraged to refer to that review. The findings remain unchanged, although some relevant papers have been written since (e.g. Staples et al, 1997; Banasi et al, 1999; Orford et al, 2006; LaMarsh, 2015). The main findings of the review were as follows:"

Jan 1, 2018

By Balmer Neilly

We are regularly told that before making a new investment one should seek the advice of his banker. If we were to place the subject matter of this paper before bankers. other than those who have experience in our mining camps, their reply would probably be evasive. However, if for example: a mining company asks them for a loan and offers as security certain mining investments, they are, in most cases, explosively candid. The idea is preposterous, unless, under Section 88 of the Bank Act, the mining company is able to deposit with the bank, gold or silver bullion, to an amount sufficiently in excess of the loan, to provide for what the banker describes as a reasonable margin of safety in case of contingencies. In addition the directors of the mine personally must jointly and severally guarantee payment of the loan. With any of these conditions missing the banking atmosphere becomes chilly. The local manager explains that the general situation, and particularly European conditions, are so unsettled that head office has warned him that his discretionary powers must not be exceeded under any circumstances.

Jan 1, 1924

By H. Chaouki

The aim of this work is to simulate the forming process of a green anode. For this purpose, a nonlinear compressible viscoelastic constitutive law is presented. The concept of natural reference configuration is considered. Within an isothermal thermodynamic framework, a Helmholtz free energy is proposed to take into account the nonlinear compressible deformation process occurring between natural reference configuration and current configuration. A dissipation potential is introduced in order to characterize the irreversible aspect of compaction process. Thus, the constitutive law is formulated through two equations: 1) an expression of Cauchy stress tensor and 2) a differential equation characterizing the evolution of the natural reference configuration. Material parameters are assumed to be a function of the bulk density. This allows capturing the micro-mechanical phenomena within the chosen macroscopic approach. An experimental study based on compaction tests is carried out in order to characterize the mechanical behaviour of the anode paste. A user's material VUMAT subroutine for finite element dynamic explicit analysis has been developed and implemented in the ABAQUS commercial software. To evaluate the model predictive capability, numerical simulations of the compaction forming process of anode paste were performed. Simulation results show that the constitutive law predicts the experimental trends and gives interesting physical responses. This constitutes a first step toward making a benchmark with experimental results on the forming process of anode paste.

Jan 1, 2011

By P. M. Dranchuk

"""PLANET EARTH seen from space appears as a fragile and limited life-supporting system in a vast emptiness. That such a view is, in fact, an accurate one is now more widely accepted than it was not long ago, before Earth's problems of over-population, overconsumption, limited resources and environmental degradation attained the limelight. The danger is that a government and public now deluged by doomsday prophecies and bemused by equally confident reiterations that technology will cure all may hesitate in coming to grips with the problem, in the hope that, given time, it will go away."" With these words, Preston Cloud begins a recent editorial, in Science(l), in which he presents a brief resume of some of the findings of the Committee on Resources and Man of the National Academy of Science-National Research Council(20.Their report, which is based on a two-year study by an extremely competent group and consists of some 250 pages of text, is even more far-reaching and sobering than the report on Energy Resources(3). It begins by quoting Sir Macfarlane Burnet as follows:""There are three imperatives: to reduce war to a minimum; to stabilize human population, and to pre-vent the progressive destruction of the earth's irreplaceable resources.(4)"

Jan 1, 1971

By Link. Theo A.

Introduction Since the discovery of a major oil pool at Leduc, Alberta, on February 13th, 1947, the long spell of 'oil drought' in Western Canada is now being turned into an oil and gas flood which requires immediate action to obtain the optimum economic benefits. The Woodbend, Section 9, and Okalta extensions of the Leduc field itself have been established; the Redwater pool, lying thirty-seven miles northeast of Edmonton, has been discovered and is being drilled up, and the Imperial Schoepp No. 1 or Golden Spike discovery holds promise of something phenomenal in view of the 500 feet of oil-saturated coral-reef porosity whose areal extent is not known. Imperial Stanolind Barrhead No. 1, northwest of Edmonton, revealed the presence of oil in the Madison, and just recently Gulf N.J. Ellis No. 1, some sixty miles southeast of Leduc, found commercial production in the Leduc D-2 discovery zone. In addition to these Paloeozoic discoveries, gas and oil reserves have also been established in the Upper and Lower Cretaceous, which must be penetrated by all tests on the way through the geological column to the Devonian. If ever there appeared to be an index of 'things to come' in the oil industry, this is it. However, without these recent discoveries the picture in Western Canada does and always did, look very promising indeed. A brief survey of the geological setting in Western Canada is the object of this contribution.

Jan 1, 1949