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

"Molecular Recognition Technology (MRT) is a simplified, green chemistry process with applications in selective separations of Ni(II), Co(II), and platinum group metals in primary ore beneficiation processes and secondary recovery operations from spent products, scrap, and environmental waste solutions. Simplification in MRT processes is achieved by non-use of solvents, reduced space requirements, and a simple separation system involving columns packed with metal-selective SuperLig® resins. Minimal waste is generated and metal recovery is achieved at 99% levels from g L-1 to <mg L-1 concentrations. MRT systems are attractive technologically and economically compared with solvent extraction, ion exchange, and precipitation separation processes. Commercial examples of MRT use include removal of impurity metals Cd, Cu, Ni. Fe, and Pb to mg L-1 or lower concentration levels from Co streams to produce battery-grade Co. Highly purified Co is required for optimal function of lithium ion rechargeable batteries and superalloys associated with aerospace and gas turbine operations. Impurity metals are recovered for reuse or proper disposal rather than being discarded to landfill. Green chemistry processes, such as MRT, are needed in metal separations going forward into the 21st century to achieve global metal sustainability in processing of native ore and treatment of secondary sources.INTRODUCTION Maximizing efficiencies of metal separations and optimizing metal recovery rates during separation processes are important goals on the road to achieving metal sustainability. Achievement of these goals is consistent with stated principles of green engineering (O'Connor, Zimmerman, Anastas, & Plata, 2016) and green chemistry (Anastas & Eghbali, 2010). Molecular Recognition Technology (MRT) separation processes using SuperLig® resins have a 25-year record of performing competitive, commercial metal separations with metal recovery rates approaching 100% (Izatt, Izatt, Izatt, Krakowiak, & Bruening, 2017). SuperLig® resins are characterized by high selectivities for specific metals over concentration ranges from g L-1 to mg L-1 or lower. MRT systems use no solvents and are simple in design and operation resulting in reduced capital and operating expenses."

Jan 1, 2017

By Stratton-Crawley R., G. E. Agar

"A study has been done of the scale-up of laboratory bench-scale flotation to continuous plant circuit performance. It was found that the impellor speed and the air flow rate influenced the results and in this case extreme values of these operating variables were required in order to reproduce the plant rougher results in the laboratory. Despite the experimental uncertainty introduced by these extreme values, it was demonstrated that the plant performance could be predicted and experimentally reproduced with bench-scale tests.IntroductionThe mineral processing industry relies heavily on batch flotation testwork to design flowsheets, evaluate reagent s and compare various types of ore. The batch tests are generally regarded as being directly comparable within themselves, but quite often they relate poorly or not at all to continuous circuits. Obviously this dilemma generates considerable uncertainty with wide-ranging ramifications. One of the manifestations of this unfortunate situation is the commonly expressed opinion that ""it may work that way in the laboratory, but it will never work that way in the plant"".In a previous publication, a method was described whereby the results of batch bench-scale tests could be used to simulate a locked cycle flotation test series. The work to be described here is a continuation of that investigation with an extension to the simulation of an actual plant circuit. It would have been preferable to progress from laboratory batch data to a continuous pilot plant and then finally to a full-scale plant operation. However, because that possibility did not present itself, an attempt will be made to show that the performance of an existing plant circuit can be successfully simulated from batch data. The success of the procedure can be judged by the agreement among the plant results, a locked cycle test and the predicted results based on batch tests."

Jan 1, 1982

By J. Béland

"Three stages, each characterized by a particular sedimentation, magmatism, mineralization and deformation, are recognized in the geological history of Gaspe. The first stage led to the formation of the Taconian orogen, the second to that of the Acadian orogen and the third stage to the accumulation of a post-orogenic cover. The Taconian orogen includes volcanic and detrital rocks of Late Precambrian or Cambrian and Lower to Middle Ordovician ages in which ultrabasic intrusions have been emplaced. Folding is severe. Mineralization is of the Cr-Ni-Cu type, related to the igneous facies.The rocks constituting the Acadian orogen include two distinctive sequences corresponding to two successive sub-stages. The second substage began in Early Devonian time with the first pulses of the Acadian orogeny. The rocks of the first substage grade southward from a nearly platformal sequence to an assemblage implying less stability and spotty volcanism. The second substage was one of synorogenic deposition of elastic rocks, first in a marine environment and later under terrestrial conditions. Granitic intrusions, surrounded by aureoles of skarn and hornfels in which Cu-Pb-Zn mineralization is found, accompanied the Acadian deformation. The second-stage"

Jan 1, 1969

By Michel Aubertin

Using mine wastes as backfilling material for underground stopes has been a common practice for more than 60 years. Waste rock and tailings are used as filling materials because they are available at a reasonable cost to support the rock walls. Backfilling is also very advantageous because it reduces the amount of mine waste disposal on the surface. In underground mines, the backfill must first ensure stability of the opening, while increasing recovery of ore and minimising dilution. It is thus critical to accurately evaluate the pressures exerted on the walls and on the barricades placed near the base of the stope. In this presentation, existing solutions for evaluating the stresses on stope walls and barricades are briefly reviewed. The authors then present recently developed analytical solutions that take into account the stress transfer from the backfill to the walls in the stope and access drift. The stress state solution, which is based on arching theory, considers the influence of the stope geometry and barricade position within the drift. The method gives the pressure generated by partly or fully submerged backfill. The solutions apply shortly after backfill deposition, when the effect of pore water pressure cannot be neglected, and also for long term conditions under a fully drained state. Experimental testing and numerical modelling results are used to validate the proposed equations. Both numerical and analytical results show that the total pressure on barricades can be significantly increased by water pressure, while the effective stress is decreased (compared to dry or drained conditions). A discussion follows on the implications of the results for backfill applications.

Nov 1, 2008

By J. S. Vanderploeg

I WILL begin this presentation by citing the annual per capita use of copper in Canada. This is best calculated by taking refinery domestic sales, plus imports of the products of foreign fabricating mills (very little refinery copper is imported), and deducting the exports of Canadian mills. No attempt has been made to estimate the copper content of imports or exports of machinery, motors, etc., but the trade balance here is probably against Canada. In any event, we find that, though varying somewhat since the war, the estimated yearly per capita figure has reached a high of 18 pounds. This is practically on a par with the United States. The rest of the world uses an average of about 2 pounds per capita, yearly, though this includes some countries, such as Sweden, Germany and England, which consume much better than average quantities. It looks, therefore, as if the Canadian copper industry has not (as has been generally charged) been asleep after all.

Jan 1, 1962

By M. Fan, H. E. Wyslouzil, J. Kohmeunch

Eriez HydroFloat(TM) separators and Canadian Process Technologies (CPT) flotation columns have been developed to overcome the limitations of traditional flotation cells in recovering coarse and fine particles, respectively. The flotation column can effectively separate 30-5 µm phosphate. Several industrial-scale HydroFloat separators have been installed in phosphate and potash beneficiation plants. Industrial-scale ultra-coarse (+850 µm) phosphate separation results suggest that a more-than 40% BonePhosphate- of-Lime (BPL) recovery increase and a 37% collector consumption reduction can be achieved. The paper describes the applications of Eriez HydroFloat separators to coarse particle separation and the CPT flotation column to fine/ultrafine particle flotation.

Jan 1, 2009

By H. Fujiwara, T. Ito, T. Mizuguchi, K. Kawasaki

"In this study, we characterize the high-temperature deformation of typical “Class I” solid solution Al-Mg alloys as a superplastic elongation attributable to the solute drag creep of dislocations. The second-phase particles formed by adding Fe or Si as impurity atoms to the Al-Mg alloys impeded the gliding motion of dislocations, thereby decreasing their hot ductility and resulting in cavity formation. High-temperature tensile tests were performed with initial strain rates in the range of 1×10–3 to 1×10–1 s–1 at air temperatures 673–723 K. The dominant high-temperature deformation mechanism in these alloys was the solute drag creep controlled by the interdiffusion of Mg in Al. In this study, the calculation of critical length, defined by the diffusion-based relaxation of the stress concentration region around second-phase particles, is reported using the Needleman–Rice parameter. An analysis of the impact of cavity formation based on a comparison of the Needleman–Rice parameter and second-phase particle size is also reported.INTRODUCTION Aluminum alloys with high specific strengths are utilized as structural materials for transportation machines to minimize their weight, which consequently maximizes fuel efficiency, environment preservation, and so on (Miller et al., 2000; Heinz et al., 2000; Starke & Staley, 1996; Polmear, 1996; Immarigeon et al., 1995; Burger, Gupta, Jeffrey, & Lloyd, 1995; Ye, 2003). Microstructure refinement by severe plastic deformation (SPD) has been performed on a laboratory scale to achieve a higher strength of crystalline materials (Valiev et al., 2006; Song, Ponge, Raabe, Speer, & Matlock, 2006; Beyerlein & Toth, 2009; Sabirov, Murashkin, & Valiev, 2013; Sauvage, Wilde, Divinski, Horita, & Valiev, 2012). At room temperature, grain refinement strengthens the material, as given by the Hall-Petch relationship (Hall, 1951; Petch, 1953); at higher temperatures, superplasticity can be expected (Sherby & Wadsworth, 1989; Edington, Melton, & Cutler, 1979; Furukawa, Horita, Nemoto, & Langdon, 2001; Langdon, 2006). However, the synthesis of large-size materials by SPD processes is not yet feasible."

Jan 1, 2018

By J. C. White

"This paper was prepared for and presented at a lecture series on ""Materials Randling"" at McGill University. The development of trackless mining at Gaspe Copper Mines, Limited is described, showing the changes in mining method and the part played by the mobile equipment in the evolution of this highly mechanized underground operation. Comparisons of loading and hauling machines are given and an attempt is made to predict some possible future developments.INTRODUCTIONTHE PROPERTY OF GASPE COPPER MINES LIMITED is located in the Gaspe Peninsula of the Province of Quebec, 60 miles west of the village of Gaspe and 25 miles south of the St. Lawrence River. The original discovery of low-grade ore was made at Copper Mountain in 1921. Subsequent exploration revealed the richer Needle Mountain orebodies, and eventually in 1951 the decision was made by Noranda Mines to build the mining, concentrating and smelting complex (Figure 1). Construction and development of the mine was commenced in 1952 and production started in 1955."

Jan 1, 1968

By Jason Palmer

"Water in mining is the commodity that has driven the mining industry for decades. Often used frivolously, modern economic and social pressures are forcing change to use less water and to improve the quality of water and effluents. Used in many processes, water is ultimately consumed in tailings disposal and technologies which can increase the recovery of water are constantly being developed. Filtration and thickening are often seen as competing technologies for water recovery however new cases are developing that show significant advantages can be achieved by combining the two technologies to develop the most effective solution. Supported by case studies this paper investigates the merits of each of the technologies and which strategies of combining the two produce the best outcomes.INTRODUCTIONMineral processing applications generally require water for the processing of ores, whether utilising physical or chemical methods. Water is first added in the milling stage and additional water added as required throughout the circuit. Water losses from the circuit are principally associated with the tailings stream. Optimised water recovery is necessary both because it is a scarce commodity and to minimise the environmental impact.Water recovery is usually accomplished through a sedimentation or filtration processes. Water can be removed from the tailings impoundment by evaporation but this does not improve the mine’s water consumption. The water recovery methodology also determines the water quality; increasing water recovery concentrates solutes in the process water and may create recirculating loads of fine solids."

Jan 1, 2016

By S. Beitler

The availability of renewable energy does not meet the demands of consumption. Hence, fossil fuels will continue to be an important energy source, and coal promises to cover the requirements for the coming decades. Because of its high energy content, deep lying bituminous coal and anthracite are important for energy generation. One trend in the future of coal mining is thin seam mining, because thick seams more and more have been exploited. A well-known and approved longwall mining method for thin seams is plowing which has big advantages compared to a shearer because of its compact design. The extraction of those thinner coal seams will become more and more important in coal industry and therefore the plow will receive more attention in future. Most approaches in longwall automation are focused on the shearer and need a more or less intelligent exploitation machine. Therefore those approaches cannot be used for the plow technology. The authors introduce a shield-data-based horizon control (SDHC). The developed approach integrates the shield data provided by the roof support and process monitoring into the horizon control process to keep the plow in seam even if the seam trend changes. This control concept can be used for the shearer as well as for the plow. The basic idea of SDHC for plow application will be introduced in this paper and first simulation results will be shown.

Aug 1, 2013

By J. E. Nesset, F. Rosenblum, J. A. Finch, R. Payant

ABSTRACT Under certain conditions of moisture and oxygen, sulphides can spontaneously self-heat. We tested a hypothesis that galvanic interaction between some sulphides can promote self-heating. Galvanic interaction is controlled by the rest potential difference between sulphides and particle size. A series of binary sulphide mixtures was tested. Individual sulphides and mixtures with low rest potential difference did not self-heat, but mixtures of high rest potential difference did. When testing pyrite-sphalerite mixtures, self-heating increased inversely with particle size, with the fineness of the pyrite governing self-heating, indicating the rate-limiting step is the reduction reaction. The results support the hypothesis that galvanic interaction contributes to sulphide self-heating. A possible mechanism based on hydrogen sulphide as an intermediate product is proposed. The understanding gained will be of interest to those involved in storage, shipping, and disposal of sulphides.

Jan 1, 2012

By Steven W. Wilson, Brigitte Lacouture, Nichola A. McKay

"The Aqqaluk deposit is a lead-zinc ore body that lies immediately north of the Main Pit at Teck Cominco’s Red Dog Mine in Alaska. It is scheduled to begin production in 2011 or 2012. A project team was formed in late 2004 to plan and implement an ore characterisation and metallurgical evaluation on the Aqqaluk ore. The main objective of this program was to facilitate the transition from Main Pit to Aqqaluk ore in the Red Dog concentrator. The program will develop a detailed, spatially-oriented characterisation of the Aqqaluk deposit attributes including lithology, ore geochemistry, bulk mineralogy, ore texture, as well as evaluating the metallurgical characteristics of ore hardness, process water geochemistry, bench-scale floatability and mineral liberation in ground feed, concentrate and tails. Developing correlations between the metallurgical response and the ore characterisation data is key to the emerging science of geometallurgy. This on-going program is a technical due diligence study that aims to reduce the risk associated with processing a new ore and to provide predictive information for mining and stockpile preparation.The test work to date has focused on characterising the five ore zones currently identified in the Aqqaluk deposit, namely: Siliceous (sub-divided to High Zn:Fe and Low Zn:Fe), Vein, Median Plate and Baritic ores. It identified a number of challenges associated with surface oxidation, or weathering, of the core samples and outlined a program for future sample collection and storage. Metallurgical testing evaluated ore hardness by a variety of methods. Preliminary floatability studies have been completed and some initial links have been established between the ore characteristics and the flotation response. Soluble mineral weathering products, the relative abundance of pyrite and marcasite and the iron content in the sphalerite grains have all shown a correlation to mineral recovery.As new core is received, both the ore characterisation and the metallurgical testing will be continued with a view to strengthen the existing correlations and develop new links."

Jan 1, 2007

By L. Chunpongtong

The Athabasca oil sands mineable resource is located in northeastern Alberta, Canada. In oil sands mining, the ore zone is regulated to have a minimum mining thickness of 3 m and a cutoff grade of 7 wt.%. The current algorithm that is widely used to flag ore zones and waste zones tends to overestimate oil reserves and causes low-grade ore to be processed. This paper presents the development of a more complex algorithm that is more representative of the actual oil found during operations and that can prevent low-grade ore from being sent for processing.

Jan 1, 2014

By Brian A. Ferguson, Raynald O. Vezina, Marielle Gaudet, Raoul R. Boissonneault

"Kiena has been committed to developing a fresh management and employee relations approach since the commencement of production in 1981. The functional organizational structure encourages joint participation and commitment on the part of all employees to common goals in safety and production. The results over the last four years have been extraordinary. Kiena won the John T. Ryan Canada Trophy for 1983 for its safety record and has experienced a steadily increasing productivity through the application of new mining equipment and technology in the hands of a well-trained and motivated team of employees.This paper serves to highlight the fact that productivity, safetyand technical innovation are closely linked to employee participationand involvement which are likely to be the key to theCanadian mining industry&apos;s survival in the years ahead.This presentation follows up on an earlier unpublished paper, given at the 84th Annual Meeting of CIM in Quebec City in April, 1982, which discussed the philosophy and the planning which took place before implementation of the management and employee relations system at Kiena. This present paper reviews and expands on material given in the earlier work. IntroductionThe mining industry, which has always been considered as rather conservative in its approach, has experienced with some regularity, cyclical periods related to metal prices. These cycles, previously foreseeable to some extent have become less coherent over recent years during which time the industry has had to face fierce international competition. The issue to productivity is without doubt the major concern of the mining industry in Canada today and it represents the greatest challenge facing us during the present decade. Developments that have been made in mining technology over the precious two decades have failed to completely produce the significant advancements in higher over-all productivity that were expected."

Jan 1, 1987

By R. Tomás, J. B. Serón, M. Romana

The Slope Mass Rating (SMR; Romana, 1985) geomechanics classification was developed as a sequel of Bieniawski’s Rock Mass Rating (RMR) system, which was almost impossible to use in slopes due to the extreme range of the correction factors (up to 60 points of a maximum of 100) and to the lack of definition of them. A detailed quantitative definition of the correction factors is one of the advantages of SMR classification. During the last thirty years the use of SMR system has been extended to many countries from the five continents and, thus, it is time to review the most interesting developments. Both RMR and SMR are discrete classifications, depending on the values adopted by the variables that control the parameters. This can cause major changes in the parameters value due to small differences in the variables value, with changes in the final rock mass assigned quality. On the other hand, geomechanics quality indexes are extremely biased. To avoid this problem, some authors have proposed continuous functions for SMR. This classification has been also adapted for its application in heterogeneous and anisotropic rock masses, for high slopes, for is application trough stereographic projection and Geographical Information Systems, has been used as susceptibility rockfall parameters and has been included in the technical regulations of several countries. Additionally, some open access computer tools have been developed for the computation of SMR. Consequently, this paper reviews: 1) the most important modifications and adaptations of slope classifications which derive directly from SMR; 2) the use of SMR throughout the world; 3) many significant papers on slopes analysed with SMR all over the world; and 4) future trends in the use of SMR.

Jan 1, 2015

By Colin Lindsay

"The Collahuasi copper mine, located at an altitude of 4300 meters above sea level in northern Chile, commenced operations late in 1998. The mine is currently the 4‘h largest copper producer in the world and comprises an open pit, a 60,000 tpd sulphide concentrator, a 15,000 tpd oxide heap leach and SWEW plant and a 200 km concentrate pipeline to a port facility.Constructing, commissioning and operating a mine at high altitude presents unique challenges in terms of the performance of both equipment and people. It is important that these be recognized and carefully considered during the feasibility study and the detailed design stages and the success of the Collahuasi project is largely due to this. The plant design incorporates a number of features aimed at mitigating the problems of altitude and the construction methodology also took into account the particular site conditions.This paper discusses the Collahuasi project team’s approach to planning for the remote location and also some of the problems experienced during construction, commissioning and operation.INTRODUCTIONThe Collahuasi mine is located in northern Chile, some 250 km to the south-east of the port of Iquique and 15 km from the Bolivian border. The mine facilities lie between 3800-4300 m above sea level on the Altiplano, the central plateau of the Andes mountains, and cover a total of approximately 95,000 hectares. Although the area is arid, it experiences an average of 150 mm of precipitation annually and weather conditions can be extreme. Temperatures during the day range between -3 to +11 º C and are generally below 0ºC at night, sometimes as low as -20°C. High energy winds are common and humidity is low. Much of the precipitation occurs during the winter as snow but there also occurs a period during the Chilean summer known as the “Invierno Boliviano’’ (or Bolivian Winter) which is characterized by severe electrical storms and rain."

Jan 1, 2001

By Fathi Habashi

"A process is proposed for the treatment of phosphate rock for the recovery of uranium and the lanthanides. The process assures the production of phosphatic fertilizers without polluting the environment with radioactive material.IntroductionWhile many processes for uranium recovery from phosphoric acid produced by the H2S04 route are known and utilised commercially, little is known about uranium recovery from phosphoric acid produced by the HN03 route1. Advantages of the latter route are both the elimination of the gypsum disposal problem, and the possibility of radium disposal in a controlled way2. Further, the lanthanides originally present in the rock can be recovered if the nitric acid route is used; they will be mostly lost in the gypsum produced by the sulphuric acid route3. In the present work a scheme for the recovery of uranium and the lanthanides from phosphate rock without interfering with the normal route for fertiliser production is proposed using HN03 as a leaching agent. Attention was also given to uranium decay products and their separation so that they might not contaminate the fertiliser4. Further, an attempt was made to defluorinate the leach solution in order to upgrade the fertiliser and at the same time recover the fluorine5. Rapid analytical methods for the determination of uranium, radium, and lanthanides in phosphate rock were developed6,7."

Jan 1, 1997

By P. Klossek

It is estimated that China accounts for 94% of the world supply of rare earths (Roskill, 2011). This fact, together with the impact of China?s export policy, poses a substantial risk to the security of the rare earth supply as well as a rare earth price risk. This situation has motivated an increase in the number of rare earth projects under development, i.e., there are currently more than 440 worldwide (Technology Metals Research, 2012). However, economically and environmentally acceptable processing technology to produce tradable products from rare earths (e.g., separated rare earth oxides) is not freely available on the market at the moment. In this respect, a lot of research and development has been initiated on this topic, in academia as well as in industry. Using a proprietary model and scenario-based analysis, we studied the impact that the development of rare earth processing technologies would have on the rare earth market and the economic feasibility of rare earth projects mentioned before. The analysis showed that this impact varies depending on the technology type (e.g., technology can affect project production volume, cost structure or both) and the legal context of the invention (e.g., free or limited by patenting availability of a new technology). The effect of a technology which influences project production volume is not the same as of a technology which changes project cost structure. The impact of a patented processing technology differs from the impact of a processing technology which is freely available on the market. In the case of a new technology which is limited by patenting, its impact depends on the market position (?producing?, ?next-coming?, or ?not producing? project) of the patent holder. The paper contributes to existing research by studying the dependence of the expected micro- and macroeconomic impact of rare earth processing technology developments on the properties of a new technology (e.g., costs, legal framework etc.). By this means, the paper adds to existing knowledge and attempts to make the rare earths market more transparent and predictable from a perspective outside China.

Aug 1, 2013

By Paolo Toscano, Dave Hall

"This paper discusses the project history, process design and layout of the Rainy River Gold Project mill. The circuit consists of a 55 x 83 primary crusher, 15 MW SAG mill and 15 MW ball mill. Both mills are twin pinion with LSS and VFD drives. A pebble crusher is located in the process plant with bypass and stockpile options. Gravity concentration followed by 30 hours of leach residence, carousel CIP, carbon recovery, cyanide destruction and tails disposal in a 1,428 hectare tailings management area (TMA).The Rainy River Gold Project is located approximately 65 km northwest of Fort Frances in north western Ontario. The project is scheduled to be commissioned and reach commercial production in mid-2017. Expected cost is $US877M and is comprised of an open pit mine, process plant, tailings management area and supporting infrastructure. The process plant is designed to produce gold/silver Dore’ bars.The project has been developed on the following timeline:• 1967 – First exploration• 1994 – 17 zone discovered• 2004 – 433 Zone discovered• 2005 – Rainy River Resources Ltd. purchases property • 2006 - ODM zone discovered• 2007 - Cap Zone discovered• 2008 - First NI-43-101 Resource completed• 2012 - PEA completed & Intrepid Zone discovered• 2013 - New Gold acquires Rainy River Resources• 2014 - Updated feasibility study completed & Environmental Assessment report submitted• 2015 - Detailed Engineering >95% complete, EA approved and construction commencesThe property is accessed by provincial highway 600 and is within 17 km of 230 kV power line and railway sidings. Key project criteria are summarized as follows:"

Jan 1, 2016

By Stephen G. Mlot

Technical Study Work ?Technical study work enables informed decisions: -Obtain a higher price for a quality asset -Minimize expenditure on a project that won?t provide adequate returns -Optimize expenditure on a project to capitalize on the potential return

May 1, 2013