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By Etienne Roy Grégoire

Since the early 1990s, the Canadian mining industry has been increasingly defined by the signing of Impact and Benefit Agreements (IBAs) between mining companies and Aboriginal peoples. While these agreements are intended to complement the legal system, they also serve to establish the legitimacy of mining projects and to encourage the harmonious integration of these projects into their social and environmental contexts. Beyond their practical implications, what are the effects of such agreements on the ability of Aboriginal communities to access the institutional space where the authorization of mining projects and the conditions of their implementation are decided? Can we view IBAs as a preliminary step towards the operationalization of the principle of Free, Prior and Informed Consent? This paper aims to explore the potential of IBAs as a sustainable solution to the legitimacy issues that result from the implementation of the formal regulatory framework governing mining activities in this jurisdiction. We highlight what constraints and opportunities the James Bay and Northern Quebec Agreement (JBNQA) engenders for local communities and draw attention to the ways in which the negotiation of the Raglan IBA and the environmental evaluation processes act upon each other. We find that certain structural problems - and problems of legitimacy ? related to mining in Northern Quebec cannot be solved by the sole signature of an IBA, which suggests the need for caution when considering such agreements as a panacea. The Raglan case demonstrates that IBAs, like other modes of regulation relying on the direct interface between companies and communities, would benefit from a stricter framework and more explicit ties with official regulation channels.

Aug 1, 2013

By C. Cristonffanini, S. Nazari

"In the past, simulation was considered to be an offline tool disconnected from plant operation. Advancements in the computation power combined with utilizing physics and chemistry sciences have allowed us to significantly improve the modeling and simulation technology for mining and mineral processing. This paper investigates the benefits of first principle models and simulation by connecting them to real time operation. Process data are connected to high fidelity models executed in parallel to the operation. In recent literature, this concept is known as Digital Twins. The Digital Twin is used for various purposes such as optimization, virtual instrumentation and condition monitoring. Using IDEAS™ simulation software we are able to construct a digital twin for different equipment inside a mineral processing plant. Two case studies for building a digital twin for the primary hydrocyclone feed pump and thickener underflow are presented. Using the pump’s model, a digital twin is developed and is installed in a gold extraction plant that is able to infer the slurry density in real time. Additionally, it is used for detecting sanding in the pipes and impeller condition monitoring.INTRODUCTION Since the eighties, thanks to advances in computation technologies, computer based simulation of processes using first principle models has become a well-known engineering tool for various industries. As our understanding of processes has increased, their representative models have become more realistic and more sophisticated. Due to this increase of accuracy, use of simulation is becoming more fundamental in process industries. The main goals to use accurate simulation is to decrease the engineering and construction cost, optimize the process design and improve the operation performance by decreasing operation cost and increasing efficiency. The term Digital Twin was first introduced in 2010 by NASA (Shafto et al., 2012) in aerospace industry. Subsequently, the concept quickly spread through other industries. As of today, no standard organization has provided an official and unique definition of Digital Twin for process industries. However, there are three important aspects that are common throughout various descriptions. When simulation is core functionality of the process (1) along the entire life cycle of the plant (2) with direct linkage to operation (3), it is called that process has a Digital Twin. According to Gartner, the concept of Digital Twin has elected as fourth most important disruptive technology for the year 2018 (https://www.gartner.com/, 2017)."

Jan 1, 2019

By C. Edwards

ABSTRACT: Milling operations in northern Saskatchewan’s Athabasca Basin have produced uranium continuously since 1975. During that period, the Athabasca Basin has been one of the world’s premier uranium camps, yielding more than 660 million lb (299,370,964 kg) of U3O8. In this paper, the author describes former and current milling operations and discusses why and how the milling process has changed and developed over the past 35 years. The author’s considerations for the future of uranium extraction in the Athabasca Basin conclude the paper.

Jan 1, 2012

By C. R. Whittemore

IT can be truly stated that no branch of the engineering industry has progressed more rapidly in the last few years than that of welding. In spite of depressed economic conditions, this industry has continued to advance along scientific lines, replacing the old hit-and-miss method of welding. The development work is intensive, and increased activity is recorded in every sphere of the industry, new applications of existing methods, together with new processes, being added to those already proved in practice. The general acceptance of the welding processes can be measured by their utilization as a manufacturing tool in the metal-working industries. Many manufacturers have partially or wholly adopted welding. These concerns have on their staffs welding specialists, design engineers, and metallurgists, who are qualified to design and supervise the manufacture of welded parts, at a considerable saving to the purchaser. The steady, consistent, and sound growth of welding is based upon investigation of the fundamentals of the various processes, together with their proper application. The classification of welding processes varies in different countries. In Europe, they are divided into two main classes, namely, heterogenous and autogenous. In the former, the parts are joined, as a ruler without melting the edges, and by using as filler a metal different from that of the object welded. Such welding differs from soldering and brazing in that higher temperatures are required to effect the union of the parts. In autogenous welding, the parts are joined by melting of the edges, with or without the addition of a material similar to the parts being joined.

Jan 1, 1936

By A. Eslami

When producing high grade mattes in smelter plants, copper losses in the slag are inevitable. Hence, the recovery of copper from slag has been the focus of many research projects, copper flotation being a widely used process. In the Khatoonabad converter, 200 t/d of slag are presently produced with a grade of 2.3% Cu. Assuming a 85% recovery by flotation, about 3.9 t/d copper could be produced, which is of prime importance economically. In the present work, a sample of this slag was crushed and ground in the laboratory to liberate the copper-bearing minerals. Following mineralogical studies, optimum laboratory flotation parameters were obtained, resulting in 90.27 % recovery and 9.42% of copper grade for the rougher stage. At pilot scale, a pulp of 28% solids was floated at ph 10.5 using 40 git of Z6, 25 git of R407 and 20 git of MIBC and A65. A recovery of 83.52% was obtained for a concentrate grade of 28.36% Cu. In the rougher cells, the feed consisted of particles 94% finer than 74 microns whereas in the cleaning stage, particles were 95% finer than 44 microns. Based on the obtained results, the Sarcheshmeh Khatoonabad converter slag is presently being fed to the Chargonbad flotation plant, where a concentrate of 32% copper at 86% recovery is being produced.

Jan 1, 2007

By R. Wang

"Under high stress conditions, rock bursts, borehole breakouts, and spalling events are common phenomena that occur around underground openings. In general, together these three phenomena represent brittle failures of an intact rock mass; however, individually they reflect different failure modes under high stresses. After analyzing and comparing the stress-to-strength criteria for rock bursts, borehole breakouts, and spalling events, proposed by previous researchers, it is found that these brittle failure phenomena share common stress-to-strength prerequisite. The stress-to-strength preconditions for brittle failures can be defined by the ratio of the maximum tangential stress around an underground opening to the uniaxial compressive strength (UCS) (s?max/sci) or by the ratio of the maximum far-field principal stress to the UCS (s1/sci). Both these indicators can be used to reflect the same stress preconditions. For s?max/sci, a ratio of 0.4±0.1 represents the critical stress requirement for brittle fracture. However, for s1/sci, a ratio of 0.15±0.05 should be considered as the critical stress requirement. Numerous engineering case studies and analysis of rock mechanics based on the Hoek-Brown criterion also verify these two stress-to-strength preconditions. Here, these two indicators are presented with an error range because complex rock mass quality ratings, lithology, and geotechnical conditions have profound impacts on the stress-to-strength preconditions for brittle failures. INTRODUCTIONHigh stresses are one of the most important factors that must be considered when undertaking underground rock mass projects (Kaiser et al., 1998). Wang et al. (2009) reviewed current progress in the evaluation of high stresses and their corresponding criteria. However, after clarifying the definition of high stress, civil engineers need to understand the deformation and failure behaviors of rock mass around an opening under high stresses. Under high stress conditions, the deformation of rock masses around an opening can be categorized into two groups, i.e., severe brittle failures (or rock bursts) and compressional plastic deformation of the surrounding rock mass, as indicated in Figure 1."

Jan 1, 2015

By A. Mazhary

"Although sensor-based ore sorting has gained significant attention recently, sorting gold deposits still face a high level of skepticism by gold mining companies. In order to shed some light on the matter, this article looks at two different gold deposits that were examined using X-ray Fluorescence, Electromagnetic and X-ray Transmission sensors. The heterogeneity of each sample is measured based on the assay results of each particle and is related to its sortability. Multivariate linear regression analysis was also performed on the XRF results to find potential proxy elements for detecting gold. The results from these deposits were varied and each sample showed different levels of sortability. While both X-ray sensors proved efficient for different deposits, the electromagnetic sensor failed to produce any promising results. Despite unsatisfactory result for one sample, this technology can have significant advantages in terms of lowering the operational costs and improving head grades and recoveries providing that the deposit is amenable to such separation methods. Therefore, it is important to mention that sensor-based ore sorting is ore and sensor dependent, and as a result, it cannot be applied and be beneficial to all deposits. Therefore, amenability tests are required in order to examine the potential for sensor-based ore sorting before one can reject the idea.INTRODUCTION Although sensor-based ore sorting has gained significant attention recently, sorting gold deposits still face a high level of skepticism by gold mining companies. Except for a few cases presented previously, no new case studies have been published. Previously, mines such as Kloof Gold Mine in South Africa used an optical sorter to sort their waste stockpile in 2003–2004 (Von Ketelhodt, 2009) and then again in 2009 (Von Ketelhodt, Falcon, & Falcon, 2011). More recently, Coeur Operations utilized an XRT sorter for their Kensington Mine in Alaska (Lasley, 2014) and also Anglo-American Platinum used an XRF sorter to pre-concentrate Platinum Group Metals through an algorithm that used chrome, copper and nickel as proxies (Rule, Fouchee, & Swart, 2015)."

Jan 1, 2017

By M. Massinaei

Recently constructed circuits have included multiple stages of columns in a variety of applications, from roughing to cleaning. The Miduk copper concentrator (in south-eastern Iran) is one of the unique mineral processing plants which use column flotation cells as rougher. As the bulk of final concentrate is produced by rougher columns, optimized metallurgical performance of these cells is crucial. This paper will present the study and optimization of, a froth washing system of columns. For this purpose, the cross-sectional area of orifices was increased and their orientation altered. Concentrate assay for copper and silica, in addition to bias rate were found to be the assessment criteria. Modification of the wash water system resulted in increasing the purity of rougher and final concentrate. Negative bias and short-circuiting of wash water into the concentrate launder were the main causes of improper froth zone washing in the former system.

Jan 1, 2007

By Piotr Malkowski

Studies on the properties of rocks heated to high temperatures are rather rare. Such research is occasionally conducted for example; in areas around nuclear power plants. The national Polish coal gasification (underground coal gasification, or UCG) project has, however, forced the analysis of the geomechanical properties of heated rocks in the vicinity of a designed geo-reactor. Ukrainian experience with UCG show that rocks up to 2 m from the burned coal seam be at a temperature > 600ºC. Such a high temperature will undoubtedly influence their physical properties. This paper presents studies on the strength and deformation properties of carboniferous rocks in the Upper Silesian region, where the UCG process is planned. Three types of rocks were tested: claystones, mudstones and sandstones. Laboratory tests of these rocks evaluated compressive strength, elastic modulus and weight loss. An evaluation of the results of the tests comparing the thermal conductivity of rocks and their specific thermal capacity was then carried out. All of the rocks studied were heated to 300, 600 and 1000ºC, and also evaluated at room temperature. This procedure shed new light upon the behavior of heated rocks in relation to their distance from the designed geo-reactor. The test results presented were developed within Research Task No. 3 ?Developing a technology of coal gasification for efficient production of fuels and electric power?, financed by The National Centre for Research and Development under strategic research and development programme ?Advanced Technologies for Energy Generation.?

Aug 1, 2013

By P. D. Waters

"Mineral deposits are where you find them; they have no allegiance to territorial boundaries. Over the past decade much of the new investment in mining has been outside of continental North America, let alone Canada. The larger Canadian Banks have pursued this offshore business through their multi-national organizations; this reflects both the increasingly international orientation of today's business environment, and to a degree, the competitive advantage of these offshore developments.The current oversupply situation in mineral markets and the increasing maturity of the Developed World Economy reduces the need for new mining projects relative to growth' in GNP. Those that are brought on stream in the future due to their competitive advantage, will continue to be pursued by lenders and equity investors alike. IntroductionProspects facing those who search for mineral wealth were described rather well more than 200 years ago by a Scottish professor of moral philosophy, who also happens to be the father of modern economics.In search for new mines, Adam Smith wrote in The Wealth of Nations, ""there seems to be no certain limits either to the possible success or to the possible disappointment of human industry"".How true that statement remains today, where we are seeing economic cyclical problems compounded by basic fundamental structural change within the mining industry.Despite the enormous advances in earth sciences during the past two centuries, the rewards of mineral exploration still remain uncertain. Even though a promising orebody is found, ultimate profitability may still depend on the vagaries of the marketplace, where large and unanticipated changes in supply, demand and prices can play havoc with the best of calculations.The Canadian mining industry has had its share of disappointment during the past few years, with savage competition, shrinking demand, declining prices, and disappearing profits. But it has also had some share of success, such as at Hernlo, which now seems certain to provide some of the lowest cost gold production in the world"

Jan 1, 1986

By W. G. Hubler

It has been within only the last two or three years that enough progress has been made in preferential flotation to warrant metallurgists in recommending the installation of commercial-sized plants for the treatment of copper-zinc-iron ores. Until the new processes had been worked out successfully, the treatment of this type of ore had proved a stumbling block in the path of metallurgical progress. Separation of lead-zinc ore is comparatively simple. A lead-zinc ore low in iron may be separated and concentrated by gravity con-centration, provided it is not necessary to grind too fine. Owing to the specific gravity of chalcopyrite and sphalerite being so nearly the same, however, their separation by gravity concentration is out of the question. Complex lead-zinc-iron ores in which the several minerals are intimately associated, requiring fine grinding to free them, have been successfully treated by flotation for the past fifteen years. Galena is easily floated, and its flotation, unlike that of chal¬copyrite, is not affected by the reagents used to inhibit the flotation of sphalerite and iron sulphides. When an attempt was made to use the methods of lead-zinc se-paration on copper-zinc ores, it was found that the depressant re-agents added to inhibit the flotation of the iron and zinc minerals would, under certain conditions, depress a large part of the copper. It was also recognized that, in the grinding of copper-zinc ore, soluble salts were generated which were detrimental to flotation unless properly controlled. The main part of this paper will be a discussion of solutions in the grinding circuit in relation to the pro¬duction of soluble salts and their effect on flotation.

Jan 1, 1931

By Michael L. Free

The hydrometallurgy curriculum for undergraduate students at the University of Utah has evolved to contain a variety of tools to help students understand and apply hydrometallurgy in a context that has industrial relevance. In order for students to perform as engineers in an industrial hydrometallurgy setting, they need to understand thermodynamic and kinetic fundamentals and be able to apply these fundamentals to extraction, concentration, and recovery applications. Students must also understand related environmental, economic, and assessment issues in hydrometallurgy and be able to work with others. In order to meet these needs, the hydrometallurgy curriculum includes a variety of relevant subject information, on-line resources, laboratory experiences, and team work opportunities to help prepare students for careers involving hydrometallurgy. The development and use of these resources will be discussed in this paper.

Jan 1, 2014

By Dorothy Walters

As an increase in the number of producers alters fact ors affecting supply, long-term prospects in traditional markets for many minerals weaken. At the same time, conflicts between national and international objectives undermine existing competitive elements in mineral markets and Canadian costs escalate. Such changes may dramatically alter the environment in which the mining industry operates.

Jan 1, 1979

By D. Shen, J. Cheung

Variable reactance arc control by the SPLC (Smart Predictive Line Controller) has been installed at many different mining sites and steel processing plants around the world. Since its first installation 18 years ago, many advances have been made to both the technology, and to its integration with furnace processes and plant operations. The SPLC has helped to improve electric arc furnace stability by reducing electrode movement while maintaining flat line arc power. Stable furnace operation at higher average power increases productivity. This paper summarizes the progression of electro-technology at Hatch since the 1970s, including fixed and variable reactance, digital electrode regulation, and fast variable speed hydraulics for Soderberg electrode, as demonstrated and benchmarked through projects and lessons learned over the years.

Jan 1, 2015

By J. Armitage, J. Erskine

Feed level and thickness measurements are essential in the optimization of an electric arc furnace. A precise measurement of the feed thickness and level gives operators the ability to increase the smelter efficiency and reduce the maintenance cost. Hatch has developed a radar system which is an affordable, low maintenance, and accurate level measurement system. The radar units can be installed across the furnace to measure the feed level and the feed thickness can be calculated with one slag level sounding. The present paper describes the development of radar systems as a process optimizing tool by furnace controls. The authors will discuss the challenges involved in installing eight radar units on the roof of a six-in-line electric furnace.

Jan 1, 2015

By Jaeheon Lee, Junmo Ahn, Isabel F. Barton

"Newmont’s Mike prospect, currently undeveloped, is a blind Cu-Au(-Zn) deposit on the Carlin Trend, containing >8.5 M oz. Au, 1027 M lbs. Cu, and 809 M lbs. Zn as Carlin-type gold and polymetallic Cu-Zn minerals in Paleozoic lower-plate carbonates and shales. This project was undertaken 1) to examine the effectiveness of different lixiviants for leaching the Mike supergene Cu-Au ores via bottle roll tests, and 2) to determine what ore minerals resist dissolution in each leaching agent by comparing the mineralogy and chemistry of head and tail samples. Sulfuric and sulfurous acids were used to leach copper and cyanide was used to leach gold. Thiourea, glycine, and other lixiviants were used to leach both base metals and precious metal. QEMSCAN and SEM study of six samples of different ore types and grades indicate that the Au occurs as varieties of native gold, including auricupride and electrum. Major Cu minerals are native Cu, cuprite, malachite, chrysocolla, and conichalcite (Ca-Cu arsenate), with locally significant Cu in jarosite and goethite. Gangue mineralogy is dominated by quartz, sericite, chlorite, alunite, smectite and kaolinite, K-feldspar, and iron oxides (sensu lato). Results of bottle roll tests and leach residue mineralogy will be presented and discussed at the conference.INTRODUCTION Resource and Geologic Setting The Mike deposit is a large, blind Cu-Au(-Zn) deposit in the Maggie Creek district of the Carlin Trend of Nevada, USA, near the Gold Quarry mine (Figure 1). The mineral inventory, based on drilling, is 8.568 Moz. Au, 1027 M lbs. Cu, and 809 M lbs. Zn at average grades of 0.72 g/t Au, 0.34 wt% Cu, and 2.13 wt% Zn (inventory for a cone at $400/oz Au and $0.80/lb Cu by Norby and Orobona, 2002)."

Jan 1, 2017

By J. C. Gilbert

"IntroductionTHE PURPOSE of this paper is to discuss in a general way the heavy oil situation in Western Canada, and particularly to acquaint those in the oil industry who have not participated in the heavy oil end of the business with past and current developments. The author has covered •briefly the location of the heavy •and asphalt-base oil fields, their geology, current drilling and production practice, the location of the •refineries capable of handling heavy crude, their products and markets, and the problems and future prospects of the industry.Location and Description of FieldsThe term heavy oil is generally used to denote crude of 20.9° gravity and under. Since the products from heavy oil are also to a lesser extent obtained from asphalt-base crudes of higher gravity, some mention will be made here of the latter; but in general the emphasis of the paper is on heavy oil as such.In the order of their production to date, the heavy oil fields and those light oil fields which produce asphalt-base crudes are : Lloydminster, Taber, Vermilion, Conrad, Princess, and Wainwright.The Lloydminster oil field has not only produced most of the heavy oil, but also is currently the largest producer, supplying at the present time about 80 per cent of the heavy and asphalt-base crudes produced in Western Canada."

Jan 1, 1952

By J. Keith Haddock

"Introduction The Coal Valley Mine is operated by Luscar Stereo (1977) Ltd. with the Alberta Energy Company having a minority interest. The mine produces 2.0 million tonnes of bituminous thermal coal per year. Deliveries include 1.5 million tonnes to Ontario Hydro and 0.5 million tonnes to the export market via bulk handling facilities on the west coast near Vancouver, B.C. There are a number of mining methods utilized at the mine including open-pit by truck and shovel, strip mining with large draglines and stripping with scrapers. The mine is located 100 km south of Edson, Alberta. Geology The coal measures are concentrated within a 210-metre int~rval of the Paleocene section. The coal seams were originally named by the mining companies in the earliest days of development of the area and these names continue to be used today. Of the five main seams, only three are presently economic to mine based on quality, thickness and depth of cover. These are the Val d'Or, Upper Silkstone and Mynheer. The Coal Valley Mine is located in the structurally deformed foothills area of Alberta and the structure of each mining area is therefore very complex. The general bedding strike is 305 degrees azimuth but major thrust faulting and folding has extensively deformed the natural seams as a closer examination will show. The Mynheer Seam, located at the base of the coal measures, ranges in thickness from 5 m to 10 m and has numerous bentonite and shale partings. Because of inherent geological features, the Mynheer Seam has been subdivided into two zones, the Mynheer 'A' and the Mynheer 'B', and the mining of coal in these zones has necessitated the utilization of distinctly different mining methods. The structural regime of the Mynheer 'A' zone consists of an overturned asymmetrical anticline crest containing a steeply dipping major thrust fault which has raised the seam above the present topographic level. Further extensive shearing and rotation of the coal has resulted in the coal taking a 'pod' shape. The Mynheer 'B' Zone is a continuation to the southeast along strike from the Mynheer 'A' Zone. The bedding dips to the southwest at an average of 12 degrees and is interrupted at the south end by a transverse fault and to the north by its outcrop at the surface."

Jan 1, 1985

By C. Riveros, H. Henein

Bulk Metallic Glasses have a high potential as advanced engineering materials due to their various properties including strength and corrosion resistance, to name a few. This paper investigates amorphous phase formation and rapid solidification characteristics of impulse atomized Co-based alloys in order to understand and control the application properties of the final products. Amorphous fraction and kinetic crystallization properties of the atomized Co-based alloy powders were quantified by means of Differential Scanning Calorimetry. In addition, different but complementary characterization tools were used to analyze microstructures of the powders. These include optical microscopy, X-ray diffraction and micro-hardness tests. While the amorphous fraction within the powders is promoted by high cooling rate and smaller powder size as expected, hardness is found to decrease with the fraction of amorphous phase.

Jan 1, 2015

By Ernest A. Hodgson

A SERIOUS hazard which must be faced in some mines, though quite absent in others, is that of rockbursts. Bursts cannot be wholly avoided in such mines, but the hazard would largely disappear if they could be predicted. The problem of prediction resolves itself into that of measuring pressure in the mine and determining when that pressure nears a critical value. The geophysical approach to the problem lies in discovering some physical property of the rock, which varies with pressure, which can be measured for rock in place, and for which the indication of critical conditions is sufficiently definite and open scale. A physical property, suggested first in connection with earthquake pre-diction, is that of sub-audible snapping. It was argued that, as the pressure grows, the rock probably yields microscopically and that minute snapping occurs which is so faint as to be inaudible to the unaided ear. Experience has proved this to be the case. Following other earlier work begun early in 1939, experiments with this method were initiated at Lake Shore Mines in 1941, and equipment was slowly being developed in practice when, fortunately, it was found possible to by-pass this tedious development programme. Experiments with sub-audible snapping in mine rocks had been carried out by Dr. L. A. Obert of the U.S. Bureau of Mines and his associates over a period of about four years. An amplifier and a recorder were developed, each reasonably satisfactory in practice. Lake Shore Mines offers a tempting field for rockburst research. Dr. Obert was invited to test his equipment in this and other mines in Ontario and did so. As a result, he and the administrative personnel of the Bureau became interested in the Lake Shore experiments co the extent of most generously arranging for the manufacture of sets of their own designed equipment for use in this programme. The first three sets of recorders were ordered at once and were delivered in May, 1942. A second group of three sets, incorporating various improvements indicated by experience both in the United States and in Canada, reached Kirkland Lake in April, 1943. The pick-up devices, known as geophones, were made in the electronics laboratory at Lake Shore by Mr. Zack Gibbs, who has had charge of all the instrument development in this re-search.

Jan 1, 1943