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By Mike D. Riley, Alan V. Bell, Ernest K. Yanful

Acid mine drainage (AMD) research under the MEND program has been ongoing since 1988 at the Heath Steele Mines waste rock piles including sulphide material, outside Newcastle, NB. In 1989 approximately 10,000 mt of waste rock was placed on a prepared sand base with an underlying impermeable membrane. The waste rock pile was heavily instrumented for measuring oxygen concentrations and temperatures. In September 1991, a composite soil cover designed for the Heath Steele climatic conditions, using local soils, was placed over the pile, creating a totally enclosed system. Moisture content and oxygen probes were installed within the composite soil cover to monitor changes within the soils over time, while two large-size lysimeters were installed below the cover to monitor the hydraulic conductivity of the cover. The waste rock site has been monitored on a monthly basis since installation of the cover, for performance of both cover and waste rock. The monitoring shows very clearly that the placement of the composite soil cover has had a major impact on the generation of AMD. Major reductions in temperature and oxygen concentrations within the waste rock pile indicate that the cover has significantly inhibited the oxidation reaction that generates the AMD. Performance data have shown that the cover has maintained its integrity under the climatic conditions of the area.

Jan 1, 1995

By Li Qihou, Li Yuhu, Liu Zhihong, Liu Zhiyong, Yang Xiaofeng

Scorodite samples were synthesized, in adding or without crystal seed respectively by using Atmospheric Scorodite Process (ASP), Hydrothermal Scorodite Process (HSP), and Improved Atmospheric Scorodite Process (IASP) individually; and their crystal structure, crystallinity, morphology, particle size, specific surface area, Fe/As mole ratio, as well as the leaching stability were characterized, aimed to reveal the relationships among the synthesis methods, the compositional and structural properties, and the leaching stabilities of scorodite. The results show that synthesis methods have significant effects on the compositional and structural properties of scorodite. Scorodite samples of high crystallinity, small specific surface area, and low Fe/As mole ratio, possess high leaching stability. The order in the leaching stability of scorodite samples synthesized in this study is as follow: ASP<HSP<IASP. Scorodite particles in the sample synthesized by IASP without crystal seed are in large sizes and of pyramidal morphology enclosed mainly by crystal planes of {111}; and the sample possesses the crystallinity of 84.5%, the particle size (D50) of 28.2 m, the BET specific surface area of 3.72 m2/g, and the Fe/As mole ratio of 1.05; after leaching this sample by using acetate buffer solution of pH 4.95 for 10 days, the total arsenic concentration in the leaching solution is merely 1.14 mg/L.

Jan 1, 2015

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 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 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 G. Kachaniwsky, M. Bédard

"The Noranda Continuous Smelting Process at the Home smelter was commissioned in March 1973. The ability of the process to handle a wide variety of feed materials and a steady stream of technical innovations in recent decades has served to maintain the Home as an efficient and versatile custom smelter. This paper reviews recent technological development and capabilities in areas such as sampling and preparation of secondary and complex materials, as well as the smelting and related environmental control issues. Future trends and improvements are also addressed.IntroductionThe Noranda Home smelter commenced operations in 1927. It was originally designed to treat 910 tonnes per day of copper concentrates and ores coming from the new Home mine site. In the 19305, the company opened its doors to other mines in northwestern Quebec. Treatment of feed materials on a custom basis has, therefore, always been an important factor in the operation of the Home smelter. Throughout the years, the Home gradually increased its custom smelting capacity, while maintaining its production from the Home mine. By the early 1950s, 65% of the materials processed was from outside customers, and by 1974, this figure had increased to more than 85% . With the closure of the Home mine in 1976, the company extended its smelting operations beyond ore and concentrate, and began to treat more scrap metals and residues rich in copper and precious metal content.Corresponding with the ever-changing pattern of feed sources, the Home smelter has adopted technological improvements to meet new and challenging business conditions. The technology of the original smelter of 1927has been completely replaced over the years in the quest for improvement. One of these major changes occurred in 1973 with the start-up of the Noranda Process Reactor. This extremely efficient smelting system has been exploited to treat a wide variety of copper and precious metal (PM) containing custom materials. This paper reviews recent developments and improvements achieved at the Home smelter, in the receiving, sampling and treatments of copper and PM scrap and secondaries, with particular emphasis on the development of new technology and equipment in complex feed materials treatment."

Jan 1, 1991

By A. Scheltema Beduin, H. Oterdoom, A. Haaks, C. Kempe, A. Liedtke

"For the Kazchrome DC Ferrochrome plant, SMS-group specifically designed an electrode column that would minimize downtime. Special features include the possibility for on load electrode jointing, on load slipping, and back-slipping. Electrode consumption is strongly related to furnace load and impedance, and is very low at high loads, which makes the graphite electrode an alternative to consider even in AC applications. The electrode could also be applied in other DC applications, as for example TiO2 slag, the novel Conroast process, or (twin) DC FeNi furnaces, and could possibly be installed during bigger shut downs. This paper will describe some of the design considerations and operational performance data on this novel column in the FeCr industry that could also be of interest for the FeNi or PGM industry if these would continue to develop towards DC technology.INTRODUCTION Every DC furnace has a cathode and an anode. The anode applied is commonly known as the Concast design, though the original design was by ABB who handed it over to Concast, subsidiary of the SMS-group. Some well-known DC furnaces outside the steel industry where the Concast bottom has been installed are listed in Table 1 as well as a few other key design features.Sidewall cooling and some other data have been left out for reasons of space, and being a lesser relevant design feature to this paper. HES stands for Hollow Electrode System, in which feed is charged through an electrode. Table 1 is built up chronologically according to first start-up date. Below comments are given to briefly explain some of the columns in Table 1: •,“Arm” in the “Cathode” column means that the design of the cathode holding and regulating mechanism consists of an electrode arm as depicted in Figure 1. •,Charging is relevant as some operations started with HES charging, whereas recently most new operations have started without HES but only charging chutes, of which at least some are close to the electrode and possibly others installed closer to the sidewall. •,“Dome” in the “Roof” column means that the design of the roof involves a center piece that can be exchanged if worn. •,The optimal roof design still seems to be a topic of debate, where no design is without problems."

Jan 1, 2017

By Z. Zhang

Aluminum boron carbide particulate reinforced composites have found new applications in nuclear industry due to their special capability to capture neutrons, Recently, Alcan successfully developed a liquid metal mixing process to fabricate Al¬B4C metal matrix composite instead of powder metallurgical technology. In the process, titanium is added into the composites to control interactions between boron carbide particulates and aluminum matrix, To understand the effects of titanium on the composites, the solidification microstructure of Al-16%B4C without or with titanium was examined by optical and electron microscopes. The results show that titanium can improve the uniformity of the particulate distribution within aluminum matrix if the titanium content in the composites is more than 0,5%, Furthermore, it is found that the layer with rich titanium on the surface of the particulates can limit the formation of AlB2 type compounds, which may greatly deteriorate the fluidity of the composites, In addition, it is also found that the amount of the reaction products in the composites increases with the increase of holding time. However, the rate of the increase is mitigated by the increase of the content of titanium in the composites. Besides, a procedure was proposed and implemented for the evaluation of uniformity of particulate distribution within aluminum matrix.

Jan 1, 2005

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

By Q. Chen, J. H. Zhang, M. Zhang, F. M. Zheng, Y. J. Zhang

The characteristics of air bubbles and gas dispersion in KYF flotation cell are studied using the method of the point conductivity probe and CFD simulation. With increasing of speed, the velocities of air bubbles increase slowly and the distribution of diameters exhibits little change. With increasing of aeration rate, the gas holdup is increased. However, the velocities and diameters of bubbles have no great change. The CFD predictions on gas holdup have good agreement with the experiment results. The gas holdup distribution in the center section is revealed. The gas dispersion in the middle and upper part of flotation cell is uniform. It would be helpful for bubbles and solid particles collision. The gas holdup of the lower part of flotation cell is scarce, and it agrees with the observation in experiment. The gas would accumulate at the suction side of impeller blades, and it would decrease the power consumption. The rotating speed and aeration rate have great effect on gas dispersion. With increasing of aeration rate, the gas holdup of flotation cell will increase. The increasing of speed would improve gas dispersion. The results are expected to help to optimize the performances of KYF flotation cell.

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 P. E. Weidmark

"PART 1-Published PapersAllcott, G.A., and Archibald, D.E.; ""Description of pillar behaviour at Heath Steele Mines""; Can Min Metall Bull; 74:834:80-87; 1981.Baar, C.A.; Discussion of Theme 1: ""Physical properties of intact rock and rock masses""; Proceedings 3rd Congress Intnl Soc of rock Mechanics; 3:32-33; 1979.Baar, C.A.; Discussion of Theme 1: ""Physical properties of intact rock and rock masses""; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3:37-38; 1979.Baar, C.A.; Discussion of Theme 1: ""Physical properties of intact rock and rock masses""; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3:38; 1979.Baar, C.A.; Discussion of Theme 1: ""Physical properties of intact rock and rock masses"" ; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3:41; 1979.Baar, C.A.; Discussion of Theme 1: ""Physical properties of intact rock and rock masses""; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3:42; 1979.Baar, C.A.; Discussion of Theme 1: ""Physical properties of intact rock and rock masses""; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3:46; 1979.Baar, C.A.; Discussion of Theme 2: ""Tectonophysics""; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3:60; 1979.Baar, C.A.; Discussion of Theme 4: ""Underground openings""; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3: 116; 1979.Baar, C.A.; Discussion of Theme 4: ""Underground openings""; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3:116-117; 1979.Baar, C.A.; Discussion of Theme 4: ""Underground openings""; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3:117; 1979.Baar, C.A. &apos;; Discussion of Theme 4: ""Underground openings""; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3:118-119; 1979.Baar, C.A.; Discussions (2) of Theme 4: ""Underground openings""; Proceedings 3rd Congress lntnl Soc of Rock Mechanics; 3:119; 1979.Baar, C.A.; Discussion of Theme 4: ""Underground openings""; Proceedings 3rd Congress Intnl Soc of Rock Mechanics; 3:120-121; 1979."

Jan 1, 1982

By A. Navarra, C. Arrancibia, R. Yañez, C. Acuña, F. Valenzuela

"Discrete event simulation (DES) is a suitable framework to evaluate and optimize the dynamics of sulphide smelters. In particular, iron-nickel-copper-cobalt sulphides undergo continual oxidation within a roasting or smelting operation, followed by batch oxidation within the converting operation, thus producing iron-free Bessemer matte (or blister copper, in the case of copper smelters); this semi-finished product undergoes further processing to produce nickel, copper and cobalt products, and to recover precious metals. The juncture between continuous smelting and batch converting is often an appropriate focus for the earliest phases of DES development, since it is typically a major bottleneck within nickel and copper smelters; later phases may include increasing levels of detail for auxiliary unit operations, as well as plant logistics. Moreover, DES can support matte-slag chemistry, including Gibbs free energy balances to determine the iron speciation within the slag. DES is therefore capable of linking the fundamentals of oxidation reactions to the intricacies of plant dynamics.INTRODUCTION Discrete event simulation (DES) is gaining acceptance within the extractive metallurgy community, as a technique that quantifies the system-wide performance of metallurgical plants under conditions of uncertainty (Wheeler & McGinty, 2015). In particular, over 90% of smelters that process nickel-copper-cobalt sulphides and copper sulphides exhibit similar semi-continuous dynamics (Crundwell et al., 2011b; Schlesinger et al., 2011b), in which the converting aisle produces batches of material that are sent for further processing (Figure 1). Thus the tools and practices that are developed for a specific sulphide smelter are often relevant to numerous other smelters.The juncture between continuous smelting and batch converting has long been a focus for discrete event simulation (Welgama et al., 1996). Nonetheless, the broad acceptance of DES in nonferrous smelters has been hindered by interdisciplinary barriers that divide industrial and metallurgical engineers (Navarra et al., 2016; Noorossana et al., 2012); this divide has been less severe in steel plants (Hollocks, 2006). In recent years, DES has been used in copper smelters to analyze crane-and-ladle motions (Coursol et al., 2009a), reverts production and consumption (Noorossana et al., 2012), and innovative control systems (Herrera et al., 2016); additionally, DES models have accounted for shutdowns and random breakdowns to provide realistic assessments of copper smelter capacities, thus guiding equipment upgrades (Campbell et al., 2013; Coursol et al., 2009a). All of these studies feature a Peirce-Smith converting aisle similar to Figure 1 that, under normal operations, constrain the smelter throughput, and are thus a bottleneck (Campbell et al., 2013; Navarra et al., 2016)."

Jan 1, 2017

By M. Epiney, A. Ghahreman, R. Kim1and

"In the presence of sulfidic refractory ores, increasing the dissolved oxygen (DO) concentration can positively affect the gold leaching rate. To identify the role of DO in gold cyanidation, electrochemical behavior was studied in the presence of 3 different ores. Sample 1 was a low sulfide pyrite ore, contained 5.14% pyrite, 0.19% galena and 3.09% S. Sample 2 was a pyriticore as well, contained more sulfide as 8.35% S, and 12.4% of pyrite. Sample 3 was a tailing of silicate gold ore, still containing75 g/tAu, 0.13% Pb and 0.18% S. Gold cyanidation kinetics were studied by cyclic voltammetry (CV) and chronoamperometry tests. With sample 1, the gold oxidation peak current density from CV curve was increased to 1.38mA/cm2under oxygen injection, while it was only 0.66 mA/cm2with air injection. From chronoamperometry test, the reaction rate was also faster under oxygen injection. Sample 2 showed similar behavior with sample 1, but the gold oxidation peaks higher than sample 1, i.e. 1.75 and 2.27 mA/cm2, under air and oxygen injection, respectively. However, it seemed that the gold oxidation was impeded by sulfide ions for a longer period. In the presence of sample 3, the gold oxidation peak was the highest among three ores –2.75mA/cm2under oxygen injection, because of its lowest sulfide content. However, from chronoamperometry test, it was also shown that the gold oxidation was impeded because of a significant amount of Pb in the ore sample.INTRODUCTIONIt is well known that gold is leached under oxidative condition (Marsden &House, 2006). Through the most representative and oldest gold leaching technique, cyanidation, more than 90% of gold can be selectively leached from an ore. According to Elsner’s equation, gold is leached in cyanide solution by forming cyanide complex [Au (CN)2–], and oxygen is consumed as an oxidant(Eq. 1)."

Jan 1, 2017

By ByongPil Lee, Changkyu Lee, Jin Gyun Park, Hyung Sub Eom, Sung-Koo Jo, Jae-Young Lee, Gilsoo Han

"A new hydrometallurgical process for nickel extraction from a low grade laterite ore such as limonite has been developed by RIST and POSCO. This POSCO Nickel Extraction Process (PosNEP) consists of five main processes: ore reduction using hydrogen as a reductant; acid leaching at atmospheric pressure and temperature; cementation by the use of reduced-ore seed; production of the main product such as ferronickel or a high purity nickel compound; and production of by-products such as cobalt and iron in the forms of cobalt sulfate and iron oxide. In addition, hydrogen produced in acid leaching and hydrochloric acid regenerated in pyrohydrolysis for iron oxide production can be reused in the process, which makes PosNEP more cost-effective. The performance of PosNEP has been proven through pilot tests, showing that this process is economically and technically viable. In this paper, basic concepts and detailed test results of PosNEP are shown.INTRODUCTIONNickel has been extracted from two types of ore, sulfide and oxide ore. Nickel and cobalt usually occur together in the ores. The principal ore mineral of the sulfide is pentlandite, (Ni,Fe)9S8, which is easily beneficiated to produce sulfide concentrates(Moats & Davenport, 2014). These concentrates are usually treated by smelting and converting to make a matte. The produced matte is then purified through either hydrometallurgical or pyrometallurgical processes to produce high-purity nickel. In general, this process for sulfide ore has been known as a more cost-effective process than that for oxide ore.The oxide ore is laterite comprised of two different ore types, saprolite and limonite. The main nickel-bearing mineral of saprolite is nickeliferrous garnierite,(Mg,Ni)6Si4O10(OH)8, and that of limonite is nickeliferrous goethite (Fe,Ni)O·OH ore (Moats & Davenport, 2014). Since the saprolite has high contents of nickel and slag formers (MgO and SiO2) and a low content of iron, it tends to be treated by a pyrometallurgical smelting process such as calcination and electric furnace techniques to produce ferronickel for use in stainless steel. In this process, the cobalt in the ferronickel does not have any economic value."

Jan 1, 2017

By J. M. Paxton, R. L. Roscoe, G. A. McCreary, W. W. Muir, T. J. Drown, D. A. Barr, T. W. Law

"This paper reviews the complete cycle of a small mining operation in a remote section of northern British Columbia, including discovery, exploration, development and production. The discovery of high-grade epithermal gold-silver mineralization occurred in 1969 following a regional geochemical reconnaissance program designed to search for porphyry copper mineralization in the Cassiar-Omineca Mountains. Exploration and development from 1971 to 1979 included geological, geochemical and geophysical surveys; trenching, almost 30 000 feet of surface and underground drilling in about 100 holes and cross-cutting, drifting and raising on the principal goldsilver- bearing vein. This led to the delineation of 100000 tons at an estimated grade of0.9 oz gold per ton and 18 oz silver per [on to an average depth of 120 feet below surface. of a 100-ton per day mining operation employing about 50 personnel with all supporting infrastructure transported to the site by a Hercules aircraft. The operation was subsequently supported by its own Twin Otter aircraft with periodic Hercules campaigns supplying major items including fuel.The mining operation included both open-pit and cut-and-fill methods. The milling operation employed conventional cyanide leach process with cyanide destruction initially by alkali chlorination and subsequently by the Inco SOl /Air process.The fly-in operation, initially structured on a 21-day-in and 7-day-out basis was modified to al-t-day-in and Z-day-out basis with no loss in efficiency and with a significant increase in employee satisfaction. The operation, which earned the B.C. Small Mines Safety A ward in two consecutive years in its Ll-month operating history, emphasized safety and process hazard awareness. Wildlife studies in the environmentally sensitive mine area also showed that industry and wildlife can coexist in harmony.Most importantly, the paper compares the feasibility assumptions with actual operating experience."

Jan 1, 1986

By E. E. N. Smith

"Uranium exploration by Eldorado prospectors north of Lake Athabasca began in late 1944 and resulted in initial discoveries in 1946 in the Beaverlodge region with mill production starting in early 1953. The operation was closed in mid-1982 having produced 21,457,947 kilograms U30 8 from the Eldorado FayVerna mine, Eldorado satellite operations and from other district producers on a custom basis.The Fay- Verna mine consists of pitchblende-brannerite orebodies spatially associated with both sides of a regional eastwest structure, the St. Louis Fault. The orebodies in the footwall (Fay) are elongate deposits of two types raking steeply to the southwest along the 50 degree south dip of the fault.One type consists of networks of fractures and veins filled with pitchblende, calcite and quartz in chlorite, epidote-altered mylonitized mica schists and amphibolites of the Middle Aphebian Tazin Group. The other type is comprised of fragments of mylonitized metasomatic quartz-feldspar granite of Late Middle Aphebian age cemented with a matrix of pitchblende, brannerite, calcite and some quartz. The vein networks lie en echelon in the footwall of the breccia ore bodies which, in part, are capped by the mud gouge of the St. Louis Fault; in other places, the breccia orebodies are overlain by basal conglomerates, grits and arkoses of the late Aphebian Martin Formation which itself immediately underlies the plane of the fault.Orebodies in the hanging wall (Verna) are a series of irregular, tabular deposits lying within a tightly overturned syncline of Tazin mica schists, amphibolites and siliceous mylonites. They consist of pitchblende, calcite-filled fractures grouped into zones and deposits displaying stratabound habits within individual rock types.Also described are several Eldorado satellite properties which were significant producers of uranium and which display complementary geology to that in the Fay- Verna mine.In general, uranium deposits in the Eldorado Beaverlodge region are closely related to minor structures associated with major faults. Uranium appears to be best concentrated where the rocks are well mylonitized and brecciated. Pitchblende fills networks of veins and fractures in metasediments and metavolcanics as well as matrix material cementing brecciated, mylonitized granite. All deposits in the Beaverlodge region lie in close proximity to the unconformity between the Martin Formation and the underlying Tazin Group."

Jan 1, 1986

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 C. R. Edwards, D. R. G. Watt

"Equity Silver Mines Ltd. a member of the Placer Development group of companies operates Canada's largest silver mine near Houston in north-central British Columbia. Initially, the silver-gold-copper flotation concentrate contained excessive levels of antimony and arsenic, so a leach process was installed to remove undesirable metals and provide improved smelter terms for the leached concentrate. The leach plant which has been fully described elsewhere (1, 2, 3), was forced by deteriorating process economics to shut down in April 1984. Equipment was mothballed and alternate uses sought.The Endako Mines Division of Placer Development Limited, located some 150 kilometres east of the Equity mine site, shut down its molybdenite mining and milling facilities in the spring of 1982. Endako has continued to produce molybdic oxide (molybdenum trioxide or MTO) via intermittent roaster runs, and also a high purity, lubricant grade molybdenum disulfide in the Ultrapure Plant. With the steel industry in the doldrums, molybdenum chemicals present an alternate and growing potential for molybdenum sales. In 1982 Placer Development began testing this market. Molybdenum chemicals were produced in the United States on a toll basis using Endako MTO as process feed. The transfer of this production to Canada was being considered when Equity's leach plant shut down, and it was noted that most of the equipment and skills necessary could be provided by the leach plant. See Figure 1.A careful investigation of process requirements was completed by engineering and production staff at Equity and Endako. A provisional capital and operating cost estimate was made, and it was decided to perform a test run during July 1984. There were strong reasons to proceed with this project. A positive cash flow was expected for both Endako and Equity. Endako would have product to continue to expand in the molybdenum chemicals market with the added selling point that now the complete production process would be under direct control of Placer Development companies. Equity would further benefit since a portion of the leach plant would continue in operation thus maintaining and exercising our hydrometallurgical engineering and operating skills. Finally, Equity would have a base from which to search out other processes adaptable to the idled leach plant equipment."

Jan 1, 1986

By J-F. Béland, N. Parson

Aluminum extrusions are widely used for automotive crash management systems due to their superior specific energy absorption capabilities, as compared to steel. The Al-Mg-Si alloy series can be readily extruded into complex multi-hollow profiles, as required in crash systems, and can be used to target a range of desired strength levels. This paper focuses on the development of an axial crush test protocol and evaluation of the crush performance of common 6XXX series alloys for a variety of tempers. The observed crush behaviour is then compared to tensile test results.

Jan 1, 2015