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By M-d-N. Gagnon, P. Okono, Y. Bergeron

In the mining industry, decisions regarding the type and number of comminution tests to be completed typically rely on geologists? observations and conclusions when studying drill cores. Given that these decisions are based on visual observations, they are essentially approximate and often inaccurate from a comminution viewpoint, causing a sizeable margin of error in estimating characterization test needs. Consequently, companies are often forced to perform more tests than necessary, requiring a significant quantity of material, and accruing significant costs. Recently, a new device, called the Hardness Index Tester (or HIT), was developed, offering users a low cost in-house mechanism for estimating the comminution parameter A*b and the Bond Ball Mill Work Index at any mine site, with potential applications on fragments up to 25 mm from drill core. In late 2016, Agnico Eagle Mines Limited initiated a trial to investigate if having an HIT device installed in a core repository would make it possible to identify the different rock properties more accurately and determine the number and type of comminution tests required. The application of the HIT was not to replace the standard comminution tests, but rather to generate a high number of comminution and geomechanical parameters for the rock mass. Ultimately, the objective would be to determine the uniformity of the rock mass and, therefore, easily distinguish any potentially problematic zones. With this method, the appropriate number of standard tests could be determined, making the HIT not only an excellent complement to the standard laboratory tests, but also an indispensable device for a geometallurgical characterization. This paper presents the results from the HIT trial using samples from the Odyssey Project, which is a Mine Canadian Malartic property.

Jan 1, 2017

By P. Schmidt, M. Hopf

Water-cooled parts of submerged arc furnaces are potentially dangerous, especially if molten matte or slag contacts the water. Explosion hazards and metal run-outs generate high costs for production loss and repairs - not mentioning the possible loss of human life. This paper reports about practical results of wear measurement on intensive water-cooled tap-holes and spray-cooled side walls. On the one hand an embedding technology has been developed, that is used e.g. in water-cooled copper tap blocks or copper side wall coolers. Second the application of the sensor installation on the inner side of a water-cooled steel shell will be discussed. The fibre-optic sensor is fed through a specially arranged piping system and measures numerous temperatures over its entire length. By using the thermal conductivity of the installed refractory materials the lining thickness is calculated. The practical installation of the sensors will be discussed and the results of the wear measurement will be compared to the theoretical FEM calculations. The highly sensitive and accurate temperature measurement, as well as the recalculation of the impact of differences in the cooling water temperature, allows the exact determination of the remaining lining thickness. The discussed technologies offer efficient and safe monitoring of tap-holes, side walls and other endangered parts of pyro-metallurgical smelters.

Jan 1, 2015

By J. F. Henderson

"IntroductionTHE National Advisory Committee on Research in the Geological Sciences was set up by the Privy Council of Canada in 1949. It was set up because you, the Geology Division of the Canadian Institute of Mining and Metallurgy, asked that it be set up. The Committee is, therefore, to a consider-able degree, your offspring. In the role of good parents you, of the Geological Division of the C.I.M., should be interested in the progress of your progeny. How is the Committee organized? What has it recommended? What has it accomplished? On behalf of the National Advisory Committee, that is what I want to tell you about this afternoon.HistoryYou will remember that, in 1946, the Geology Division of the C.I.M. set up a Committee on Geological Research. This Committee, under the Chairmanship of Dr. J. E. HAWLEY, found ""that there is no national organization interested in surveying, co-ordinating, and implementing with financial help, fundamental and much needed geological research. Accordingly, the first and most necessary step to put the geological sciences in Canada on a proper footing .is the recommendation that a National Advisory Committee on Research in the Geological Sciences be formed"" (l).This recommendation was endorsed •by the President and Council of the C.I.M. in 1947 and submitted to the Minister of Mines and Resources."

Jan 1, 1952

By K. M. Mayhew, G. D. Barr, T. M. McCoy, C. T. Knilans

"Teck Resources Limited (“Teck”) has developed and extensively tested on a continuous basis the CESL Technology hydrometallurgical process for treating copper and nickel sulphide concentrates, including bulk copper-nickel concentrates. Copper, nickel and cobalt are leached efficiently into solution, utilizing CESL process conditions. Total precious metals including gold, silver, platinum and palladium are recovered from the residue stream via sulphur flotation. This paper describes the CESL Technology testwork on a bulk copper-nickel concentrate derived from Twin Metals Minnesota?s (TMM) deposits within the Duluth complex and evaluates the economic benefits (increased cash flow, increased revenue certainty) and investment criteria (capital cost, payback and cash flow) of incorporating CESL Technology into the staged development of TMM?s deposits.INTRODUCTION Mineral Processing and the Role of Hydromet in the Duluth Complex The Duluth Complex in northern Minnesota, United States (US), represents one of the largest undeveloped accumulations of copper, nickel, gold, and platinum group metals (PGMs) in the world, ranking second in copper and PMs and third in accumulation of nickel. The figure below identifies some of the larger known deposits within the Complex (see Figure 1). Copper, nickel, PM and PGM mineralization within the Duluth Complex is hosted by mafic to ultramafic intrusive rocks that are part of the overall intrusive complex.One of the mineral processing challenges of Cu-Ni-PM-PGM deposits in this Complex is the complicated, polymetallic nature of the mineralization1: copper occurs primarily as chalcopyrite and cubanite with minor occurrence of talnakhite; nickel occurs as pentlandite and refractory nickel oxide/silicates; iron sulphides are present as both pyrrhotite and troilite; and PMs/PGMs occur in both the sulphide matrix as well as discrete minerals. An additional challenge for the Duluth Complex is the ratio between copper and nickel; in most of the identified deposits, copper grade is three to four times greater than the nickel grade, which precludes the production of a simple bulk concentrate due to the lack of a traditional smelting market for a bulk concentrate of this character."

Jan 1, 2017

By Iain Sommerville, Hugh Mountford, Dawid D. Smith, Claude Dube, Brett Hixson

JW Aluminum use lean and Six Sigma techniques to continuously improve their target of reliable, repeatable and reproducible (3R) manufacturing. Six Sigma’s second stage gate, known as "Measure" involves identification and qualifying appropriate measuring systems. Metal quality (inclusions) are known in the industry to be an important element in 3R casting. The measurement of inclusions at JW Aluminum historically depended on outside vendors. In order to establish real time inclusion measurement ability within JW Aluminum, inclusion measurement systems in the marketplace were investigated. The qualification of a MetalVision MV20/20 ultrasonic inclusion analyzer are discussed as well as the subsequent application of the system in melting and casting improvement projects.

Jan 1, 2015

By R. Cottam

The deformation and recrystallisation of magnesium yttrium alloys containing 0.23, 0.84 and 2.71wt% yttrium and commercially pure magnesium extrusion has been investigated at temperatures between 200 and 350°C. The alloys were produced as billets 7.5 cm diameter, solution treated at 525 °C for 8 h and extruded into 3 cm diameter bar at 390°C. Channel die compression was employed to deform the samples at a strain rate of 1x10-3s-1. For the 0.23 wt% yttrium alloy and the pure magnesium, dynamic recrystallization (DRX) occurred at all temperatures and the amount of DRX increased as the temperature was raised. In the alloys containing 0.84 and 2.71 wt% yttrium DRX was almost completely suppressed at all temperatures. The absence of DRX in the 0.84 and 2.71 wt% yttrium alloys was accompanied by a decrease in the ductility, except at 350°C the highest deformation temperature. It was observed that this increase in ductility was accompanied by a reduction in deformation twinning and the initiation of pyramidal slip. This work highlights the important role that DRX plays in enhancing the ductility of magnesium alloys.

Jan 1, 2006

By G. G. Campbell

"HistoricalBARYTES was mined in Nova Scotia as early as 1874 from a deposit at Five Islands, on the north shore of Minas Basin. The first record of the presence of the mineral at the Walton site appears in a report by Selwyn in l893, who states: ""Barytes in considerable quantity occurs in veins in lime-stones at Walton and Pembroke"". The exact site of the present workings was marked •on a map published by Fletcher in 1905.The economic •possibilities of this deposit, however, were not recognized until 1940, at which time we were at war with Germany, who up to that time had supplied 50 per cent of the world's requirements.At that time the Nova Scotia Department of Mines, recognizing the need for certain strategic minerals, induced Canadian Industrial Minerals, Limited, to send prospectors into 'the area to look for manganese. No manganese deposits were found, but a deposit of barytes was directed to their attention, and exploration and development work on the occurrence was proceeded with.IntroductionThe south shore of Minas Basin between the Avon river at Windsor and the Stewiacke river at Maitland has long been known as a potential source of mineral wealth. It had attracted the attention of mineralogists and in the past had produced considerable tonnages of manganese ore and gypsum. Depletion of ore in surface and near surface deposits resulted in a dwindling production, until today only deposits of gypsum are worked."

Jan 1, 1952

By L. Gonzalez-Sardi, W. McCombe, M. Pearson

Pressure oxidation is increasingly being used for processing refractory sulphide ores and concentrates because it offers highly effective base metal and precious metal extraction while minimizing elemental sulphur, arsenic & mercury emissions. Yet pressure oxidation processes introduce new safety concerns and process risks as demonstrated by a number of safety incidents over the last 20 years, including overfilling, oxygen-metal fires, nozzle/sparger failures, and uncontrolled pressure relief events. Chemical Process Safety regulations in the United States and Canada mandate that companies constructing or operating chemical process facilities perform a rigorous hazard and risk analysis based on either ANSI/ISA-84.00.01 or IEC 61511 safety standards to determine the level of protection required for each hazard in the plant. This paper describes the application and implementation of three (3) unique safety instrumented systems developed by Hatch for ensuring the safe operation of three different pressure oxidation processes.

Jan 1, 2014

By J. Girard, V. Aubé, M. Barakate, S. Bellec, M. R. Eddahabi, Y. Chaik, M. Deshaies

"The activated carbon used in the carbon-in-leach (CIL) process to absorb gold is subject to breakage. This carbon breakage can be minimized, but it will always be necessary to deal with fine carbon particles, known as carbon fines. These fines contain a significant amount of gold and mining operations generally struggle with the treatment of this product. Since IAMGOLD’s Essakane mine is located in Burkina Faso, shipping carbon fines out of the country was not considered a viable solution due to the logistical burden and legal procedures in place. A benchmarking study demonstrated the complexity of treating carbon fines on site. IAMGOLD partnered with the host government to find an innovative approach to economically recover the gold locked in these fines. This paper describes the new circuits commissioned in July 2016 built to improve carbon fines collection, incinerate the carbon fines and leach the gold in the ashes produced by incineration. These new circuits successfully demonstrate that it is possible to extract more than 94% of the gold content in the carbon fines. This is profitable for the company as it improves the overall mill recovery rate by 1.0% to 1.5% and significantly decreases gold inventory build-up on site.INTRODUCTION The activated carbon used in the carbon-in-leach (CIL) to absorb gold is subject to breakage. This breakage can occur in the CIL tanks, the stripping circuit, the regeneration process or anywhere throughout the pumping and handling processes of carbon through the circuit. Fine carbon particles are invariably created and, because of their small size, present a large specific surface which favors gold absorption (Hilsher et al., 2014). At the very beginning of operations at Essakane, the carbon fines were recovered by means of a thickener and a filter press, but the circuit was undersized and inefficient. Subsequently, a decantation basin was used to settle the fines before the thickener. The settled fines were shovelled from the basin into bags. All these bags were stored in the backyard of the plant. The average tonnage of carbon fines recovered monthly was 23.5 tons with a gold grade at 1938 g/t."

Jan 1, 2017

By E. Ghali, A. D. Bas

There is a lack of electrochemical studies of oxidized gold ores since the majority of previous studies were conducted with sulphidic gold ores. In this study, the influence of agitation and iron oxide minerals, i.e. magnetite, hematite, and maghemite on gold leaching was investigated by means of galvanic and passivation phenomena. Cyclic voltammetry studies of Roasted Gold Ore (RGO) in de-aerated electrolyte have shown one oxidation and one reduction reaction while three oxidation and one reduction peaks were observed with gold electrode. Galvanic coupling results by Zero Resistance Ammeter (ZRA) mode indicated that magnetite showed a negative effect on gold dissolution while maghemite and hematite showed a positive effect, relatively, as a result of higher galvanic corrosion rates. Generally, gold dissolution was found to increase in the initial 15 minutes. Increasing agitation speed from 100 to 400 rpm resulted in higher galvanic corrosion rates for RGO, magnetite, and maghemite electrodes, while 250 rpm was found to be optimum for hematite electrode. Passive products such as silver and iron-oxide were identified by XPS and SEM-EDS analysis, respectively.

Jan 1, 2015

By R. Esteban, D. Runnels, J. Torrealba-Vargas, G. Couture

"Data handling is an important step in the development of a simulator of a mineral processing circuit. The model requires representative data of the scenario to be modeled. The model development involves protocols that must be followed very closely to complete a successful project.Data handling of large and diverse datasets (metallurgical test results, geological data, mining models, historical data, etc.) is a key element of the model. The information needs to be processed, reconciled, interpreted, modeled and presented to support the design or the optimization of a mineral processing plant.Best practice recommends that teams from different disciplines (such as mining, metallurgy, geology and environmental) interact to define the most important variables that could influence the simulator. For example by adopting a geometallurgical approach in the earlier stages of the project, it is possible to consolidate the number of main ore rock types in a testwork program (saving money and time) by involving geologists and metallurgists in the sample selection and data interpretation.Planning the development of a model involves an understanding of the software capabilities but also the limitations and the magnitude of the data required to calibrate the model in case of changes in the project.A successful model requires a deep understanding of the circuit to be modeled and thus plant personnel should be considered as members of the team.This paper describes the use of the "state of the art" tools for data analysis, simulation and optimization; and shows three practical examples of the use those tools in the design of mineral processing plants."

Jan 1, 2015

By Jamie N. Burdeski, Susan E. Hartfield-Wünsch

Aluminum sheet use has been steadily increasing in the automotive industry to achieve mass reduction and improve fuel economy. One significant manufacturing challenge for aluminum sheet implementation is the reduced formability compared to the steel alloys it replaces. This paper includes friction results from the draw bead simulator (DBS), twist compression (TCT) and strip draw (SDT) tests, for two oil based lubricants and four hot melt lubricants. Formability testing was done with the same lubricants and materials, testing in pure stretch with a hemispherical punch, and in draw with a breadpan shaped die.

Jan 1, 2015

By A. M. S. Hussein, B. E. Rogers

Progressively more stringent emission limits and advances in regulations and enforcement have made air compliance more difficult for metallurgical facilities. This has historically required improved collection and treatment of stack sources. Fugitive emission reductions are now increasingly required to achieve compliance. Typically small in magnitude, fugitive emissions have a disproportionate impact on ground level concentrations, can be visible to the public and can influence workplace health and safety. Moreover, these emissions are complex, as they are spread over multiple sources, distance and time and are affected by various activities and conditions. As such it is difficult to find, define and monitor these emissions and their impacts. This difficulty translates to the design of emission reduction measures and operational requirements. This paper presents an overview or ‘heuristic’ of fugitive emissions management for compliance in existing operations. This includes aspects such as the impact of regulations on project scope, approaches to developing a comprehensive emission inventory, considerations for solution development and the plant’s role in sustaining compliance once achieved. Case studies are presented to demonstrate how portions of this approach have been applied.

Jan 1, 2015

By A. McGrath, M. Trovant, M. Haque

Minimizing energy consumption is a priority for many industrial facilities. Metallurgical and gasification processes produce dirty syngas (CO and H2), which offers the potential for energy recovery. However, syngas handling can pose an explosion risk and even minor leaks can result in poor workplace hygiene. Furthermore, many jurisdictions around the world now discourage wet syngas handling due to limited water availability and secondary pollution. Hatch has developed a 100% positive pressure gas handling system that targets these safety hazards without using fresh water. The implementation of a system for calcium carbide smelters at Qinghai Salt Lake Industry Co. (QSLIC) in China is profiled as a case study.

Jan 1, 2015

By J. Dennett, M. Faris, M. Antonio, M. Collins, N. Tuffrey, R. Ellenwood, V. Reddy

"In January 2012, AngloGold Ashanti Córrego do Sítio Mineração, with assistance from Sherritt International Corporation, commissioned a new autoclave for pressure oxidation of refractory gold concentrate at the Córrego do Sítio operation in Brazil. Start-up of the plant occurred in a few weeks and enhanced gold recovery was realized almost immediately, with 94% gold extraction achieved in carbon in leach (CIL), compared to less than 70% without pressure oxidation. This paper describes start-up and commissioning of the plant and provides an overview of plant performance over the last five years.INTRODUCTION In 2008, AngloGold Ashanti purchased the former São Bento property from Eldorado Gold, which, along with AngloGold Ashanti’s existing Córrego do Sítio mine, was renamed AngloGold Ashanti Córrego do Sítio Mineração (AGA Mineração). Later that year, the Sherritt Technologies division of Sherritt International Corporation (Sherritt) was contacted to begin batch and continuous pilot plant tests to determine the amenability of the AGA Mineração refractory gold concentrates to the pressure oxidation process. Based on the results of the batch and pilot plant tests, AGA Mineração requested basic and detailed engineering studies to be conducted by Sherritt, eventually leading to commissioning of the plant in January 2012. AGA Mineração’s plant is located in southeastern Brazil in the state of Minas Gerais, near the city of Belo Horizonte. AGA Mineração`s Phase 1 mine plan covers three sites in the Laranjeiras, Carvoaria Velha and Cachorro Bravo ore bodies, and is designed to process 60,000 tonnes of refractory gold concentrate per year to produce 140,000 ounces of gold per year with an 11 year life of mine (AngloGold Annual Financial Statements, 2010). Recovery of gold at AGA Mineração is based on Sherritt`s pressure oxidation technology for refractory gold concentrates (Berezowsky et al., 1991; Collins et al., 2011a; Collins et al., 2011b). This process had previously been applied to the recovery of gold at the São Bento site (Carvalho et al., 1988; de Silva et al., 1989), in a plant that was operational between 1986 and 2007 (Silva et al., 2004)."

Jan 1, 2017

By R. L. Bruening, R. M. Izatt, N. E. Izatt, K. E. Krakowiak, S. R. Izatt

The need for selective metal separations has increased as the mining industry encounters more complex ore bodies and the demand for higher performance end products expands. Molecular Recognition Technology (MRT) is a green chemistry process that involves use of SuperLig® resins to selectively remove desired metals from a variety of solutions in mining and metals processing industries. Recoverable metal concentrations can range from multiple g/L to mg/L or less. The MRT separation process is based on green chemistry principles and can efficiently produce high purity metal products with minimal waste generation and energy usage. In this paper, applications of MRT to metal recovery and purification in the minor and specialty metals industry will be presented and discussed. Examples will be described involving cobalt, nickel, zinc, rhenium, iridium, indium, germanium, bismuth, and cadmium, as well as removal of lead and iron from process streams.

Jan 1, 2015

By S. W. Marcuson, P. J. Mackey

The 1973 Oil Embargo and succeeding disruptions in supply had a profound effect on energy costs and consumption patterns in the developed world. This was especially true in the USA where post World War II growth, fueled by low-cost imported oil, left the country dependent on uninterrupted oil shipments from the volatile Middle East. In this atmosphere, Professor H.H. Kellogg of Columbia University, convinced of the necessity of good environmental stewardship by the writings of the era’s leading environmentalists, developed a methodology for evaluating energy and process efficiency of metallurgical processes and wrote a series of papers describing and applying the techniques. One of these, "Energy Use in Sulfide Smelting of Copper" is recognized as a seminal work which both described the state of energy usage in copper smelting in the mid-1970’s and portended future developments. The background to these papers is examined and the current and past Cu-Ni matte smelting practices in Canada are examined in the context of the results. Data from early 20th century publications describing reverberatory and blast furnace operation is employed to show that energy consumption for much of the century was several multiples higher than that calculated for best reverberatory operation in the 1970’s.

Jan 1, 2015

By K. J. Daun, C. J. Shi

UsiborThrough the second step heating at 900 °C, the spectral emissivity shows a gradually decreasing trend with increasing soak time, caused by the surface phase transformation from Al® 1500P coupons are austenitized in a Gleeble 3500 thermomechanical simulator using a two-step heating procedure in an argon atmosphere. Variations in spectral emissivity are measured in-situ using a near infrared spectrometer and ex-situ with a Fourier transform infrared reflectometer. Microstructural evolution and surface roughness are investigated using optical microscopy, FE-scanning electron microscopy, and a surface profilometer. A series of phase transformations of Al-Fe-Si intermetallic phases at the coating/steel substrate interface cause the surface phase and surface roughness to change, which in turn influences the spectral emissivity. At the beginning of the first heating step, the coupons have very low spectral emissivity, due to the molten Al-Si coating. Spectral emissivity increases significantly with increasing soak time from 5 to 12 minutes, associated with the surface phase transformation of the coating into Al7Fe2Si intermetallic phase and an increase in surface roughness. 5Fe2 into AlFe intermetallic phase with a decrease in surface roughness.

Jan 1, 2015

By K. Duckworth

The treatment of Turam data by conventional procedures does not permit the interpreter to make any estimate of induced current magnitudes. This problem may be overcome by using an alternative data treatment procedure. It is shown that the conventional and alternative procedures are equally satisfactory in terms of their ability to provide the location of line currents and estimates of conductor quality. A full description and evaluation of both procedures is presented in conjunction with field examples to show how the alternative procedure may assist interpretation when used to complement the conventional approach.

Jan 1, 1973

By A. Blackmore, D. Baker, L. Human

"Mechanical mixing equipment is common in a wide variety of mining, metals and process applications, such as hydrometallurgical reactors, solvent extraction, digestors, and tanks for storage of slurry or hydrocarbons. Computational Fluid Dynamics (CFD) has been applied successfully to single-phase mechanical mixing problems for several decades and is established as a reliable design tool. As computational power and CFD codes have improved over the years, there have been significant advances in modelling capabilities including improved models of turbulence, interaction of rotating and stationary components, multiphase flows, and modelling of free surface interfaces, for example. This paper will provide an overview of the application of CFD to mechanical mixing problems. First, it will review the traditional single phase Multiple Reference Frame (MRF) approach and introduce a range of advanced modelling techniques. Three examples of the application of CFD to industrial mixing problems will be given. It will be demonstrated that CFD is an effective tool for reducing technical risk in design, for identifying the root-cause of mixing problems, and testing modifications to existing operations."

Jan 1, 2015