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By C. P. Browning

Copper, as far as we know, was the first metal used by man, and due to the fact that it occurs in many places in the 'native' state, and also to the ease with which it may be shaped, it has played an important part in the evolution of civilization. Copper tools with inscriptions dating back to 6,000 B.C. are known in Egypt, where the metal probably got its start as a useful material in human hands. Just how far back the use of copper in Canada dates is difficult to say, but it was in use by the Indians in the Lake Superior country long before the arrival of the first white man. For many generations the Eskimos also have used copper derived fr0m deposits of the native metal found in the Coronation Gulf district. Due to the metal's many unique qualities, imperishable with age, ancient implements and utensils are apparently as good today as when they were made, having withstood the onslaught of time probably better than objects of any of the other base metals. Copper alloys so well with other metals that today it is second only to iron in its industrial value. Even at the beginning of the eighteenth century the world's production of copper was probably not more than seven thousand tons a year, with Great Britain producing three-fourths of this. One hundred years ago the mines of the United States, Chili, Mexico, Canada, South Africa, Australia, and Tasmania, which now produce about nine-tenths of the copper of the world, were totally undeveloped. Ln 1926 the world production of copper was approximately 1,658,000 tons, which was seventy thousand tons greater than in the preceding year; but growing demand absorbed the increased production, so that the stock of rough copper throughout the world is comparatively small. Of this huge tonnage of the metal, Canada produced four percent, two-thirds of it emanating from British Columbia, nearly one-third from the Province of Ontario, and the balance from Quebec.

Jan 1, 1927

By R. A. Wyman, F. E. Hanes

THE demand for high-quality aggregate is increasing in all phases of the construction industry and in all organizations associated with road building in Canada. The production of aggregate in Canada has increased almost continuously since the end of the war and has quadrupled since 1948. Increases during the past fifteen years can be accounted for by the expansion in all types of construction, particularly that of roads and highways. Total construction in 1959, based on preliminary estimates, has been valued at $7 billion, and an increase fore-cast for 1960 indicates optimism on the •construction horizon (1). Cement produced in Canada in 1959 amounted to 6.3 million tons. This is more than 2.5 times the 1948 production. Increased cement production indicates an increased use of concrete, and thus an increased need for aggregate. Natural sand and gravel deposits are gradually being depleted.

Jan 1, 1962

By C. Lambert

It has been shown that contacts between host rock and engineered barriers may be critical in the design of deep radioactive waste repositories. Water is expected to reach the interface zone after the re-saturation of the geological massive and its presence may lead to concrete leaching. Such a phenomenon could increase the interface transmissivity and compromise the confinement of radioactive waste. Recent experimental results from Buzzi et al. (2008) have enhanced how concrete leaching can drastically change the mechanical behaviour of such interfaces. Because of the local loss of strength resulting from leaching, shearing resulted in a degradation of the interface asperities. Similarly to rock joints, intact interfaces exhibit a usual contracting-dilating behaviour. On the contrary, depending on the extent of leaching, the degraded interface can display a fully contracting. This paper intends to investigate the influence of concrete leaching on the mechanical behaviour of host rock-concrete interfaces. The leaching process consists in the dissolution of some of the hydrates of the cement paste, leading to a reduction of the strength and Young's modulus. A discrete model has been developed with PFC3D where a simplified interface morphology has been introduced using a saw-tooth description of the asperities.

May 1, 2009

By W. Griffith

"While oxalic acid precipitation practices are commonly applied on purified rare earth elements (REEs) pregnant leaching solutions (PLS), few efforts have been reported using oxalic acid (OXA) to recover REEs directly from untreated PLS. High oxalic acid demand is the most significant issue in all these direct oxalic precipitation (DOP) practices. Preliminary research on DOP of REE from a dilute PLS originating from an acid bake followed by water leaching was conducted. At 75°C, the oxalic acid demand was between 12 and 18 times the stoichiometric requirement for complete REE precipitation. Conducting DOP at 25°C had superior REE recovery but the product purity and filterability declined. Between 75°C and 100°C, REE recovery increased with increasing temperature. When sodium hydroxide was used to adjust the pH during DOP, in the range of 0.5 to 1.5, higher pH benefited REE recovery. Using ammonium hydroxide in place of sodium hydroxide, the REE recovery was reduced by close to 5%. Sodium chloride addition to the PLS was also investigated and the results showed that at both 75°C and 25°C, the REE recovery was enhanced substantially. At 25°C, when the oxalic acid addition was controlled at 4.7 times the stoichiometric requirement, the overall REE recovery reached 95% with the addition of 240 g/L NaCl. Other reagents such as KCl, NH4Cl also showed significant enhanced REE recovery at the same oxalic acid addition. The addition of sodium sulphate appeared to largely enhance the precipitation of LREE but inhibited the formation of HREE oxalate. All results indicate the formation of rare earth double salts may play an important role in REE DOP sulphate media.INTRODUCTIONThe conventional routes for recovering rare earth elements (REEs) from a sulphuric acid pregnant leaching solution (PLS) involves an initial purification step for removal of iron, aluminium for example by precipitation through neutralization, followed by precipitation of REEs as hydroxide, oxalate or carbonate salts, or by bulk solvent extraction for REE recovery (Xia, 2013). Another route was used by Bayan Obo in their historical flowsheet, where the PLS was first subjected to double sulphate precipitation, then the remaining REEs, mostly heavy rare earth elements (HREE), were recovered by oxalate precipitation (Li, 2011)."

Jan 1, 2016

By Krishna Parameswaran

"This paper discusses energy use and conservation in the primary copper industry and illustrates eco-efficiency considerations, using select examples of practices at ASARCO LLC, an integrated primary copper producer and others in the industry that promote eco-efficiency. The World Council for Sustainable Business Development first publicized the concept of eco-efficiency at the Rio Earth Summit in 1992. Eco-efficiency is a management concept linking environmental and economic performance and is aimed at generating added value for a business through, among other things, increased resource and energy conservation and reduced environmental impacts throughout the life cycle of the product or service. This concept differs from sustainable development in that focus is only on economic and environmental factors and does not include social considerations. In the metal mining and processing context, this added value can be realized by implementing practices that promote conservation of water and mineral resources, conservation of energy, minimization of waste, reduced emissions and effluents and increased recycling. The examples from the primary copper industry used to illustrate eco-efficiency considerations include: water and energy conservation in mineral processing, adoption of flash and bath smelting processes, emission reduction and process improvement associated with fire-refining, implementation of green chemistry in electrorefining, promoting product stewardship initiatives and fostering renewable energy project on disturbed mined lands.INTRODUCTION ASARCO LLC (Asarco) was organized in 1899 as the American Smelting And Refining Company. Originally a consolidation of several lead-silver smelting companies, it evolved over the years into an integrated producer of primary non-ferrous metals, including copper, lead and zinc and associated co-products. Grupo México, S.A.B. de C.V acquired Asarco in 1999. Today, Asarco is a vertically integrated producer of primary refined copper and associated co-products such as gold, silver, molybdenum, selenium and tellurium. Asarco operates three open-pit mines and mills, two leach, solvent extraction-electrowinning (SX-EW) plants and a copper smelter in Arizona and a copper refinery in Texas."

Jan 1, 2017

By Sanat Talmaki

Construction and mining worksites pose unique challenges to workers and equipment operators due to their dynamic and unstructured nature. Narrow haul roads, crowded work spaces and presence of workers and equipment in close proximity, combined with large blind spots and overall poor visibility afforded to operators lead to collisions and run-over-type accidents between equipment, workers, and other entities that may be present on the jobsite. Operations that involve machine-infrastructure interaction, particularly in the case of concealed infrastructure such as excavation and drilling lead to unintended strikes between the equipment?s end-effect or and the infrastructure. Such accident-prone scenarios can be avoided by providing operators with real-time feedback and warnings using 3D visualization and proximity monitoring of the entities present in the equipment?s vicinity. Thus the jobsite in the real world is abstracted and represented in a 3D virtual world. However, this requires the ability to create a seamless link between real-world sensors present on the equipment and/or the jobsite and the virtual environment. This paper describes a non-restrictive acquisition allocation framework that allows position and orientation sensor streams from construction and mining job sites to be used for updating 3D virtual scenes in real-time for providing vital collision avoidance warnings to equipment operators.

Aug 1, 2013

By P. R. Warner

This paper reviews the development of certain aspects of the electrical specifications of Anglo American?s suite of specifications for gearless mill drives (?GMDs?). These specifications are based on experiences in both Anglo American?s and others? operations, benchmarking against large hydro generators, the advice of industry and university experts, and continuous close co-operation with OEMs. To achieve a step change in availability additional final testing and electrical protection have been implemented, insulation requirements have been specified for machines to be operated at high altitude and clean area and access control systems have been developed.

Jan 1, 2012

By A. C. Elliott, A. J. Lafreniere

THE Hamilton Works of The Steel Company of Canada is a fully integrated steel plant with an annual capacity of three million tons. Located on the south shore of -Hamilton bay, it is in the centre of Hamilton's industrial belt. The heavy concentration of industrial activities found in this area, accompanied metallurgical well-known sources of pollution which are normal to urban areas is creating a pollution problem which concerns both industry and the general public. The Steel Company of Canada has recognized this problem and, accordingly, has adopted the policy of integrating suitable pollution control devices into its new installations. Much effort is also being expended to control the emissions of air contaminants from the existing equipment. At the Hamilton Works, there are two main sources of metallurgical dust emissions to the atmosphere -the Open Hearth furnaces and the Sinter Plant. Of these two, the Open Hearth furnaces are, undoubtedly, the largest single source of

Jan 1, 1962

By C. R. Larsen, R. G. Bradburn, A. L. Mular, B. C. Flintoff

"Following the acquisition of grinding- circuit data at Brenda Mines Limited for simulation purposes, various methods to mass balance the circuit were evaluated. Unfortunately, different answers were obtained for different balancing methods. A data-adjustment procedure was therefore developed. The procedure assumes that all ""best-fit"" criterion. A search is conducted with the minimum set of water masses and narrow size ranges of solids around the circuit (called search variables), which permit the computation of any of the measured data points. Search variables are used to calculate measured values for an objective function of the form: [ ] where W, is a weighting factor•, M1 is a measured value and M. is a corresponding . value calculated from search vanables. The best values of M, are those which minimize R. The above method is compared with others that have been utilized for mass balancing circuits."

Jan 1, 1976

By Donald Carlisle

"IntroductionTHE OPINION is held by many persons outside the mining industry, and by some within it, that mine •operators customarily find it advantageous to mine •only the richer parts of orebodies and to leave behind, perhaps permanently, leaner material which could be mined only at a lesser profit. This opinion and the inference which might be drawn from it that 'gutting' of mineral resources is a common feruture• of the mining industry are prejudicial to the intertsts of the industry and deserve careful scrutiny. Oddly enough, a theory of mine economics which gives much support for the opinion was advanced first by members of the mining profession itself, has been repeated •several times in mining literature, and to my knowledge has never been adequately refoted.According to the theory, selective mining of the rich ore first on a large scale will yield substantial gains and these gains do not merely reflect the desire of 'money minded investors' for a quick return but derive from the logical application of compound interest rates and the concept of ;present value. W. O. Hotchkiss and R. D. Parks (1) illustrate the reasoning with a hypothetical example in which an orebody of 4,000,000 tons may be mined either in its entirety in forty years at $1.00 per ton profit or selectively with the recovery of only the richest half in twenty years at $1.50 per ton profit. They show that, with Hoskold rates of 4 and 8 per cent, the present value of profits from mining only the richer 2,000,000 tons exceeds the present value of profits :from mining the whole orebody by about 20 per cent."

Jan 1, 1953

By Yuanming Pan, Brett Rogers, Baoquan Hu, Gary Yeo, Christine Austman

The nature and distribution of radiation-induced defects (RIDs) in quartz from the Maw Zone, a yttrium- and rare-earth-element-enriched sandstone breccia complex exhibiting intense hydrothermal alteration, have been investigated by electron paramagnetic resonance (EPR) spectroscopy. EPR spectra show that detrital quartz in sandstone, from five diamond drill holes intersecting the Maw Zone and one above the crest of the so-called Quartzite Ridge, contain only background-level RIDs, indicating that Ubearing fluids were absent in this area. However, close to the sandstone-basement unconformity, in hole WR-194 immediately west of the Quartzite Ridge, the concentration of RIDs in detrital quartz is significantly above background but at least an order of magnitude lower than those at the Key Lake and McArthur River deposits. Widespread drusy quartz at the Maw Zone, which signifies intense hydrothermal alteration, is associated with hematite-, sulfide- and carbonate-bearing mineral assemblages, which exhibit complex crosscutting relationships. EPR spectra of drusy quartz in all three types of mineral assemblages are low in RIDs as well, supporting the EPR evidence that fluids at the Maw Zone did not carry significant U. These EPR results suggest that, in spite of intense hydrothermal alteration and favorable structural geology, the Maw Zone is unlikely to host any significant U mineralization. Moreover, this study shows that the EPR technique is potentially a useful exploration tool, capable of determining whether individual alteration zones in the Athabasca Basin were associated with U-bearing fluids or not.

Jan 1, 2013

By Andrew J. Freyman, George S. Barry

"Mineral endowment in northern British Columbia and the Yukon Territory was assessed on the basis of geological opinion which was gathered in a quantitative framework of subjective probabilities. The survey area encompassed 364,000 square miles and was divided into 310 cells having dimensions of one degree of longitude by one-half degree of latitude. The response solicited related to tonnage, grade and number of deposits of a particular mineral in each cell. The questionnaire sought an expression of mineral endowment down to mine-able depth as distinct from economic expectations. Details on the questionnaire and responses are presented in a series of contour maps on individual commooities, which illustrate the collective occurrence picture of the respondents. The approach is largely dependent on the cooperation of an adequate number of geologists familiar with the region being examined. This approach to an assessment of the mineral endowment of a region has a wide range of applicability, from the focusing of exploration effort to aiding government and development bodies in the formulation of regional strategies and the planning, for example, of road, rail and power facilities."

Jan 1, 1970

By F. Ajersch, M. Rigaud, M. Jallouli

"Le gonflement des boulettes d'hématite à été étudié à l'aide d'une méthode de mesure standard ISO ainsi qu'à l'aide d 'une méthode de mesure dilatométrique.La première méthode a servi à l'étude des boulettes haute silice (5% SiO2) dont l'indice de basicité (IB = CaO + MgO -i- SiO2 + Al2O3) a été ajustée soit à l'aide d'une addition de dolomie, soit à l'aide d'une addition de pierre à chaux, soit à l'aide d'une addition de ces deux composes. L'indice de basicité variait de 0.05 à 0.12. Les résultats de gonfle ment obtenus à 1000?C dans une atmosphère de 40 CO - 60 N2 ont permis de montrer qu’indépendamment de l'indice de basicité c'est la dolomie qui contribue le plus à diminuer le gonflement par rapport à la pierre à chaux. L'utilisation de l'indice de basicité comme critère de sélection des boulettes est discutée.La méthode dilatométrique a servi à l'étude du gonfle ment de deux types de boulettes préparées à partir de deux concentrés de fer et dont la teneur en silice a été fixée à 2.5% et 0 5%. Ces deux types de boulettes ont reçues les mêmes additions de liant en quantité et en nature. La détermination en continue du gonflement, à 950?C dans 40 CO - 60 N2, a permis d'une part de mieux cerner le niveau de réduction auquel correspond le maximum de gonflement et d'autre part de montrer que l’allure des courbes de gonflement est étroitement liée à la nature du liant. Une augmentation de la teneur en silice des concentres contribue à diminuer le gonflement des boulettes.Des essais de réduction de gonflement non isothermes ont été réalisés à des montées de température à 10 et 20?C/min. Les résultats indiquent que le gonflement déterminé dans les conditions non iso thermes est inferieur à celui obtenu lors des essais isothermes. On discute alors de la validité des essais standards de gonflement qui sont utilisés pour prédire le comportement des boulettes lors de leur réduction dans un haut fourneau."

Jan 1, 1983

By C. O. Stee

Introduction The property of Siscoe Gold Mines, Limited, is located on an island of three hundred and forty acres in lake Kienawisik, about fifty-two miles east of Noranda and forty-three miles south of Amos, Quebec. Lake Kienawisik is a part of the Harricanaw drainage system and is crossed by the main line of the Canadian National railway at Amos. This waterway is navigable for boats with a draught of six to eight feet. Diesel engines have been the source of power at the property since milling operations were commenced in January, 1929. The power plant as first designed and built was for a milling capacity of 100 tons. Two Polar-Atlas units, each of 200 h. p., comprised the original installation. With the growth of the 'mine, more engines were added until, at the present time, there is installed at the Siscoe what is rated the largest Diesel plant at any mining property in Canada. Definition of a Diesel 'The Diesel engine is an internal combustion engine which works with liquid fuel introduced after, and independently of, the air charge at a time when communication between the cylinder and the outside atmosphere is cut off, and which ignites the fuel by compression-beat and stored combustion-heat unassisted by heat sources outside the cylinder itself while the engine is in stable operating condition"(1).

Jan 1, 1934

By D. W. Tully

Sedimentary and volcanic rocks of the Timiskaming series trend west-ward across the property of the Upper Canada mine, forming part of the north limb of a regional syncline which is truncated on the south by the Larder Lake fault zone. A wide zone of schistosity strikes east-west through the sediments and volcanics. The central portion of this zone is occupied by a system of narrow gouge-filled fractures in highly altered rocks, mainly tuff, trachyte, trachyte porphyry and syenite porphyry. The alteration zones have developed through repeated stages of deformation and accompanying metamorphism. The initial stages were marked by carbonatization and sericitization, followed by silicification and the introduction of minor amounts of sulphide minerals. Gold was finally de-posited in relatively late fractures within silicified zones and pyrite. Repeated movements along the Up-per Canada break have offset post-ore dykes of minette and diabase, and have resulted in minor displacements within the orebodies.

Jan 1, 1963

By Edward R. Rose

This paper summarizes and emphasizes the potential importance of Canadian rare-earth occurrences, and recommends that efforts to locate and evaluate rare-earth deposits should be increased. Increasing world markets, depending on intensive applied research into the numerous unique and remarkable chemical and physical properties of the rare-earth elements (REE), are developing; their properties and uses are becoming better known; methods of separation are much improved. The REE group comprises a Cerium (Light) subgroup of 7 metals and an Yttrium (Heavy) subgroup of 9 metals. REE are trace elements in many rocks and minerals, and major constituents of more than 50 rare-earth minerals, many of which are difficult to detect and identify. They occur preferentially in acidic and alkaline igneous and metamorphic rocks, including carbonatites, as well as in placer deposits, certain uranium deposits, phosphate rocks and others. The main ores now are bastnaesite (in Precambrian carbonatite), monazite and xenotime (in Recent beach sands) as well as uraninite and brannerite (in Huronian quartz-pebble conglomerate) and loperite (perovskite) and apatite (in alkaline complexes). World resources are summarized. Twenty mines in 1973 produced an estimated world total of about 31,000 tons of contained rare-earth oxides (REO), 19,341 tons of which came from one mine at Mountain Pass, California. A selected fifteen, of 315 or more Canadian occurrences, are briefly described and compared, and their relative merits indicated. Their abundance and variety suggest the possibility of finding high-grade deposits in many geological terranes in Canada.

Jan 1, 1979

By R. N. Chakravorty

Early detection of spontaneous combustion is of utmost importance in underground coal mining to prevent major disruptions of production and to ensure a safer working environment. This paper presents the work done in developing a suitable system for the early detection of heating in a hydraulic coal mine. Laboratory studies on the products of oxidation for Balmer 10 seam coal showed that a significant amount of carbon monoxide is produced during the early stages of heating and that detection methods based on the analysis of other gases, such as hydrogen, ethane or ethylene, are not a better alternative for this coal. The four-point carbon monoxide monitoring system recently installed at the hydraulic mine is discussed in this paper. It is believed that by studying the trend of carbon monoxide concentration in the mine air, it will be possible to detect heating at an early stage. Field tests carried out so far have indicated that infra-red technology will prove to be a powerful tool in the hydraulic mine, particularly for locating hidden oxidation or fire in cracks, fissures, underground workings and coal outcrop areas before it spreads extensively. The project is jointly sponsored by EMR, CANMET, Mining Research Laboratories and Kaiser Resources Ltd.

Jan 1, 1978

By J. B. Boisvert, W. Board, C. R. Mooney

"Traditional geostatistical modelling methods are difficult to apply to heavy-tailed deposits because the extreme positive skew of the grade distribution leads to bias. The focus here is on an innovative method of modelling the high-grade population by conditionally simulating discrete volumes (nuggets) of gold with marked Poisson and Cox processes. Capping and other ad-hoc manipulation of the assay data is not required; however, an intensity map for the point processes is required. The method is demonstrated on a dataset from an epithermal deposit and demonstrates an improvement in reducing smearing and controlling the skew of the grade distribution.RÉSUMÉ Les méthodes traditionnelles de modélisation géostatistique sont difficiles à appliquer dans des gisements dont la distribution de la teneur est à queue lourde car l’extrême asymétrie positive de la distribution de la teneur génère des biais. Dans le présent article, l’accent est mis sur une méthode novatrice de modélisation de la population à haute teneur par la simulation conditionnelle des volumes discrets d’or (pépites) au moyen de procédés marqués de Poisson et de Cox. La limite d’utilisation et d’autres manipulations ad hoc des données ne sont pas requises; toutefois, il faut une carte des intensités pour le processus ponctuel. La méthode est démontrée sur un ensemble de données d’essais provenant d’un gisement épithermal et elle montre une amélioration dans le lissage du flou et dans le contrôle de l’asymétrie de la distribution de la teneur."

Jan 1, 2015

By A. G. Lylie

Introduction At the Britannia Mining and Smelting Company's mill, the equivalent of 2,500 to 2,800 pounds of copper sulphate crystals per day is made from copper which is precipitated from the mine-water. This copper sulphate is used in the mill for the recovery of sphalerite by2 flotation. From 1932 until 1936 it was produced by exposing the precipitate to air for thirty days and then dissolving the oxidized copper with dilute sulphuric acid. In 1936, the flotation of sphalerite was discontinued and, when it was resumed in 1947, steps were taken to try to improve the former method. The present paper outlines the way in which this was done, and describes the plant and procedure by which copper sulphate is now being made, and by means of which an appreciable saving is being effected. Aboratory Tests The previous work had established that the precipitate, which consists mainly of metallic copper, must be oxidized before the copper would dissolve in dilute sulphuric acid. Various methods for oxidizing it were tried but in the early laboratory work the only suitable one found was to heat the precipitate to 600°C. and hold it at this temperature for two hours. When this was done, approximately 90 per cent of the copper became soluble in .acid. This percentage was considered satisfactory for practical purposes, but the cost of roasting was prohibitive because only a small amount of roasted precipitate was required each day.

Jan 1, 1951

By Rob Boom, Yasuyuki Tozaki, Greg Traquair

The objectives of the business case are to examine a proposed metallurgical project and answer fundamental questions about project feasibility, risks, opportunities, and value. A business case fulfills these basic functions: estimates economic value; helps to understand competitiveness; serves as a risk management tool; and serves as a communication tool. A business case evolves with the project life cycle, and supports the gate reviews at the end of each phase of engineering, through to project construction and operations. A business case must be holistic, including all elements of scope that can impinge on project risk and value.

Jan 1, 2015