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By D. Knuutila, G. Goyette, James A. Finch, G. Bartolacci, A. Fortin, Chi Ho Lau, A. Lockhart

"In a COREM-McGill collaborative research and development project, gas dispersion parameters and froth properties were manipulated in a copper flotation plant to study interactions between the collection and the cleaning zones. In this paper, specific work on developing some relationships between operating conditions and froth stability in a rougher column flotation cell of 125 m3 is reported. Froth stability, measured by image analysis, was related to the following process conditions for specific flotation machines in an industrial case study: Gas flow rate, collector dosage, pH, frother type and dosage. Across the range examined, froth stability was improved through a decrease in gas flow rate and/or increasing frother dosage. Metallurgical results (grade and recovery) showed that both gold and copper were dependent on froth stability.INTRODUCTIONMcGill and COREM have over the past two years collaborated in a research and development project to merge gas dispersion parameters, frother analysis (McGill technology), and froth properties (COREM’s imaging system) to study the interactions between the collection zone (pulp) and the cleaning zone (froth). The main goal is to increase knowledge of flotation cell hydrodynamics since it is known to govern the metallurgical performance of the flotation process (Power et al., 2000). In this paper, specific work on developing some relationships between operating conditions and froth stability in a copper flotation circuit is reported.The objective of this work is to study gas dispersion in a large volume flotation column (hydrodynamics) and to measure its impact on the froth. By froth imaging, it is possible to diagnose operational problems on the basis of froth characteristics (Bartolacci et al., 2005a) and consequently, to propose ways of improving process performance by froth analysis (Bartolacci et al., 2005b).Another approach to froth characterization is investigated in this paper. In the same flotation column, a froth stability apparatus (column) was included (Triffet and Cillers, 2004). The mechanical froth stability apparatus is used to link “hard” froth characteristic measurements to “soft” froth characteristic measurements (those obtained by imaging)."

Jan 1, 2008

By K. Wood, R. McIvor, P. Blythe, M. Lavallee

A new analytical approach for characterizing and improving the performance of ball milling is presented. Individual ball mill circuit design and operating variables can be related to overall circuit performance through two distinct parameters for classification and breakage. The ball mill circuit functional performance equation is presented.Total mill x Classification x Test specific x Grinding power draw system efficiency grinding rate rate ratio= Production rate of new product size materialExamples from industrial plants and applications in the research and development field are discussed.

Jan 1, 1990

Burr Mineral Resource has: ?Grade / Thickness / Tonnage ?Dry Caprock ?Low Carnallite ?Low Clay / Insolubles ?Flat & Continuous Deposit ?Proper depth

May 1, 2009

By J. B. Keast

Introduction The last two or three decades have been marked by striking developments in methods of mining and tunnelling. In view .of increased competition and various economic factors, intensive ' mining has been largely practised, and no effort seems to have been spared to increase outputs and lower the cost of production. In metalliferous mining, the compressed-air rock-drill has effected marked savings in this direction, while in coal mining, the coal-cutting machine has revolutionized mining methods and materially contributed to economical working. Yet, for many years, little or no advance was made in methods of handling the rock, or coal, once it had been successfully broken. Loading by hand is, undoubtedly, the most laborious occupation in the whole of mining operations, and it is also the greatest single item that enters into the cost of production. In view of this, the lag of improved handling methods behind the process of winning the rock or coal is rather surprising. The point, however, was appreciated by mining men, and the introduction of various forms of conveyors and loaders is the result. The belt conveyor, the chain conveyor, the shaker conveyor, and the mechanical shovel entered various parts of the field, but it was left to scraping to provide a method of both conveying and loading. From the pure loading point of view, the choice lies between mechanical shovels and scraper loaders. While it is realised that each of these machines has applications peculiar to itself, yet it should be realised that much work which has hitherto been done by mechanical shovels can be done equally effectively with scraper loaders and at a considerable saving both from the point of view of initial outlay and upkeep.

Jan 1, 1933

By H. Sahay

This paper summarizes the history and ore-grade statistics of mining the Ming orebody, and then details the mining methods. Included are raising, stoping, drilling and blasting techniques. Particular attention is paid to ground support, ventilation and pumping requirements.

Jan 1, 1979

By P. A. Witt

"Highland Valley Copper is a conventional truck-shovel mining and flotation concentrator operation located 75 km southwest of Kamloops, British Columbia (Fig. 1).The ore is situated within a porphyry copper deposit and is mined at a rate of 135,000 mt/day from two separate open pits. The nearby mill produces concentrates containing 375 million pounds of copper and 5 million pounds of molybdenum metal yearly. In the Valley pit, head grades are roughly 0.40% Cu at a 0.23% Cu equivalent cut-off. The Valley pit strip ratio currently sits at 0.55:1 with waste quantities made up of separate rock and unconsolidated overburden units. From the mill, concentrates are trucked to nearby Ashcroft and then hauled by rail to ocean port facilities in Vancouver. The mine employs 950 people and is planned to operate until 2009. The operation is a partnership between Teck Cominco (63.9%), BHP Billiton (33.6%), and others (2.5%). Management is shared by the two principal owners and directed by a management committee."

Jan 1, 2005

By Clermont Lavoie, Marc Filion, Marcel Vallée

"Les mineralisation d'or des gîtes de la SOQUEM - Silver Stack dans is canton Bousquet se situent dans une bands de roches pyroclastiques asides du groupe de Blake River, d'âge archéen, dans le même horizon géologique que lee gites aurifères de Thompson Bousquet et Dumagarni situés plus a rest. La propriété a été explores anterieurement a maintes reprises depuis les années 1930, parfois jusqu'aux travaux souterrains, notamment par les groupes Mooshla, Warrenmac et Westwood Cadillac ainsi que par Silver Stack Mines.Ces zones auriferes se situent a l'intérieur de larges halos (jusqu'à 1,000 m x 400 in) de pyrite disséminée (2-5%) dans des tufs a lapilli et des agglomerate acides montrant des concentrations locales de pyrite. La zone 1, découverte en vérifiant par sondage une anomalie E.M., coincide avec une de ces concentrations de pyrite et la teneur en or est ici proportionnelle a la pyrite. Ce secteur se distingue par l'intensité de l'altération en séricite. La zone 2, qui s'étend sur près de 600 m, se situe dans un agglomérat acids, avec une faible teneur en pyrite, et montre de fines veinules de quartz-carbonate.Du point de vue géophysique, aucune methods ne donne des résultats probants: la polarisation provoquée montre de tree grandee anomalies correspondant aux halos de pyrite, tandis que lee concentrations de pyrite détectées par les méthodes E.M. (VLF ou EMH) sont loin d'être toutes aurifères. Les relevés magnétiques aident a établir la structure la où un certain contraste de susceptibilité magnétique est present. Les essais minéralurgiques préliminaires indiquent que la concentration de Bette mineralisation aurifère ne présentera pas de problems majeur."

Jan 1, 1977

By Greg Gosson, Larry B. Smith

"These are heady times for the mining industry, with strong metal prices, investor enthusiasm for the junior explorer and ready access to finance for mineral projects. Many projects were shelved in the past because of technical deficiencies — insufficient tonnes or grade, metallurgical problems, the deposit was too deep or too narrow, or the project was physically or economically under water. With the possibility of sustained metal prices, now is the time for those previously “challenged” projects to be re-evaluated and financing sought for continued development. The question is, do these deposits have reasonable prospects for economic extraction, as required by all mineral resource reporting codes? NI 43-101 defines a mineral resource as that portion of the mineral inventory that has reasonable prospects for economic extraction. However, a mineral resource is not simply an inventory of all blocks above a given cut-off grade. The spatial distribution and geological and grade continuity must also be considered. The qualified person (QP) must consider factors significant to project economics at the mineral resource estimation stage, and not just when qualifying mineral reserves. CIM Best Practice Guidelines for estimating mineral resources require the factors significant to project economics be current, reasonably developed and based on generally accepted industry practice and experience. In establishing the cut-off grade, it must realistically reflect the location, deposit scale, continuity, assumed mining method, metallurgical processes, costs and reasonable long-term metal prices appropriate for the deposit. Variations within the resource model (rock characteristics, metallurgy, mining methods, etc.) may necessitate more than one cut-off grade or economic limit in different parts of the deposit model. There must be sufficient knowledge of the metallurgical characteristics of the deposit, which should be supported by preliminary metallurgical test results."

Jan 1, 2003

By S. Kelebek, E. Yalcin

"Two composite samples of a gold-bearing ore from North Western Quebec (Barry Township) were tested to assess their grindability, recovery by flotation and Knelson concentrator as well as extraction using cyanidation.Work index values (BWi) for two composites were found to be 10.4 and 11.0 kWh/tonne, respectively. Flotation tests involved feed samples for which the particle size ranged from a P80 value of 205 ?m to 53 ?m, which resulted in gold recoveries of 91.8% to 95.8% (at gold grades of 130 to 140 g/tonne). Cyanidation tests indicated gold extraction levels ranging from 94.2 to 97.5%. Higher, recoveries were obtained at finer grind sizes and higher cyanide strengths. However, the grind size had a bigger impact on gold leaching. Gold grade and recoveries obtained with the Knelson concentrator device were lower than those obtained by flotation. Mass recoveries to concentrate products strongly depended on the fluidization pressure used. High gold recoveries can be obtained generally at low water pressures of 3 to 4 psi. Higher water pressures produced more selectivity at the expense of higher gold losses.It can be concluded that the gold ore samples tested have good characteristics due to moderate levels of energy requirement, high gold recoveries and extraction rates attainable.INTRODUCTIONBench scale testing of ore samples is an important step in the long series of metallurgical and economic studies involved in bringing new ore bodies into production (Coleman, 1980). Through a laboratory testing program, the behaviour of an ore in a particular process on a larger scale can be established. In an exploratory manner, this testing can be helpful for classification of ores in terms of “good ore” or “problematic ore” by providing preliminary information on recoverability of target minerals. Potential problems if any can be assessed by further investigation of products (e.g., middlings) obtained as a result of testing. A detailed bench scale experimental program in the metallurgical laboratory can also provide the background work for flowsheet development. Depending on the simplicity or complexity of the ore to be tested and type of details required from a testing program, the amount of samples required in the mineral processing laboratory can vary from several kg to more than one hundred kg depending on how detailed the metallurgical testing program is."

Jan 1, 2008

By John Kazakoff, Andrew Mortimore

"Production at the remote Kumtor Gold Mine in Kyrgyzstan commenced on schedule in December 1996.The ore mined during the first few months of 1997 from the upper benches of the pit did not produce the results predicted by the feasibility study. Low metallurgical recoveries experienced at the time were cause for great concern.It soon became clear the recovery difficulties centred around the preg robbing nature of the ore.Procedures were developed to selectively stockpile highly carbonaceous low recovery ore types. Testing methods were developed in the mill to quante the preg robbing activity of the ore. Preg robbing masking agents were added to the process to reduce the preg robbing activity of the ore.The importance of coconut carbon activity relative to the preg robbing activity of the ore was realized. Every aspect of the performance of coconut carbon in circuit was evaluated and optimized to improve carbon activity.Mineralogical analyses were completed defining the deportment of gold in ore and process tailingsBy year end the recovery difficulties had been overcome and plant design production had been achieved. Process improvements continue through 1998."

Jan 1, 1999

By D. L. Putnam

Snap Lake Mine ?? Complex dyke ore body ?? Underground operation ?? 1.1 million tonnes per annum ?? 1.2 carats per tonne ?? On-site diesel power generation ?? Supply by ice road and air ?? Milestones ? Construction commenced in 2005 ? Commissioning 2007 ? First diamonds August 2007

May 1, 2008

By Dave Bulled, Khiratt Husain

"The use of High Pressure Grinding Rolls is gaining significant interest as a replacement for SAG milling in the comminution of hard rock ores because of the potential for reduced costs in terms of energy and grinding ball consumption. Estimation of expected energy consumption for fullscale operations has conventionally involved the testing of a few fairly large samples in pilot scale HPGRs. This paper describes the development of a small-scale batch test method for determining a work index for HPGR of a large number of samples that can be used to show the variability of the ore as an integral part of a geometallurgical approach to circuit design and production forecasting.The test equipment that was developed comprises a hydraulic press with adjustable pressure operating on small batches of ore in a locked cycle test procedure. A work index measurement was determined that links the specific energy consumed in the test to the breakage achieved such that the index can be used to predict comminution energy requirements.The measurements were calibrated against laboratory scale HPGR equipment to develop a model for design and forecasting that includes crushers, HPGRs and ball mills in a complete comminution circuit.INTRODUCTIONEstimation of the expected energy consumption for full-scale HPGR operations has conventionally involved the testing of a few fairly large samples in laboratory and pilot scale machines (Danilkewich, 2006). With the financial input of five mining corporations, SGS Lakefield Research has developed a small scale test capable of providing relevant information on the variability of energy consumption and size reduction from drill core samples. It is our intention that the values measured in the test will be scaled up, through benchmark comparison with pilot sized and full sized HPGR units, to allow plant design and throughput forecast on a block by block basis of the mine plan using a new CEET program. CEET® (an acronym for Comminution Economic Evaluation Tool) is an advanced grinding design and performance predicting tool that uses energy relationships to model the performance of SAG / Ball mill circuits."

Jan 1, 2008

By A. M. Childs, R. F. Mather, K. R. Rawling

"The challenges encountered in the design and construction of mines and their process facilities today are becoming more intense and the engineering more competitive. The need to incorporate new techno1ogy to compensate for ever rising costs is always present, but its application in the harsh environment of Northern Canada increasingly requires the inclusion of new proven methods and innovative approaches to arrive at economically attractive projects.This paper deals with the development of the process design for the Cullaton Lake Gold Mine in the Northwest Territories. Particular emphasis is given to the interaction of the imposed construction and testwork schedules, and their effect on certain process decisions.The challenge that faced the project team may be defined by the following factors:1. A schedule which required that metallurgical testing, engineering, and procurement and delivery of all equipment and construction supplies should be complete within a period of ten months.2. Transportation of all personnel, equipment and supplies to the site by airlift, as no road was available or affordable.3. A six week period when transportation to the site was impossible.4. The extremes of temperature beyond the tree line in the Northwest Territories.5. A complete lack of infrastructure in the area."

Jan 1, 1983

ABSTRACT Understanding process histories and worker exposures in nickel production operations is critical in determining the role nickel compounds play in respiratory cancer incidence. As part of a series on Vale Canada’s (previously known as Inco) nickel processing operations, this paper includes descriptions of Ni electrolytic operations at refineries in Port Colborne, Ontario (1922–1984), and Thompson, Manitoba (1961–present). Industrial hygiene measurements, by area and personal sampling, of workplace aerosols at these operations are reported.

Jan 1, 2014

By Ann Lamontagne

Le parc à résidus de l?ancienne mine Dunraine contient des résidus générateurs de drainage minier acide. Le concept proposé pour la restauration du site est d?utiliser le fort potentiel alcalin des boues rouges, résidus d?aluminerie, afin de neutraliser les résidus miniers. En appliquant une certaine quantité de boues rouges à la surface du parc, on provoquera une neutralisation de l?acidité. De plus, les alcalis contenus dans les boues rouges vont provoquer la précipitation de minéraux stables (sulfates tel la jarosite). La précipitation de ces minéraux provoquera la formation d?une couche indurée qui rendra difficile la circulation de l?oxygène et de l?eau. Bien que ce concept ait été vérifié en laboratoire, ce sont là des hypothèses qui restent à vérifier dans des conditions réelles d?exposition. Les principales questions soulevées par l?utilisation des boues rouges, mis à part le contexte géochimique, est le contexte technico-économique. En effet, le transport de quantité importante d?un matériel argileux humide présente un défi économique important. Outre le défi économique, la manipulation et l?épandage de ce produit sur des parcs à résidus constituent également un défi important. Cet article présente les conclusions d?une étude technique sur le transport, la manutention et l?épandage de boues rouges sur un parc à résidus situés en Abitibi : le site de Dunraine.

Nov 1, 2002

By S. Nikolic, O. O. Kehinde-Philllps, O. T. Djamgouz, D. H. Rousell

"A bulk mining method is employed at the Lockerby mine resulting in the formation of large muck-piles. If these muckpiles remain in the stopes for some time they may agglomerate to the extent that the muck cannot be removed by a scooptram. A laboratory investigation was undertaken with sulphide material from the mine in order to detemine the time that oxidation begins and the flowability of the material as a f unction of several factors. The laboratory results are applied to the conditions in the muck-piles.The time of the beginning of oxidation of the material decreases as the sulphide composition, water content and availability of air increases. Oxidation is retarded by the addition of a copper sulphate solution instead of water. The unconfined yield force (strength} of the material increases with an increase in the sulphide composition, water content and time. The material ceases to be free-flowing before there is visible evidence of oxidation and this suggests that oxidation actually begins earlier and that agglomeration is also due to the capillary action of water.Broken ore should be removed from the stope prior to the time a muck-pile ceases to be free -flowing-perhaps as early as two days f or high-grade ore and 5 days f or low-grade ore. In order to control dust, 1.4 weight per cent of a 5 per cent solution of copper sulphate should be added 10 the muck-pile rather than water. This inhibits oxidation and increases the time that a muck-pile remains free-flowing."

Jan 1, 1984

By N. Wachgama, J. P. T. Kapusta, R. U. Pagador

The Thai Copper Industries smelter (Thai Copper) is located some 200 km southeast of Bangkok near the MapTaPhut deep sea port in one of the industrial centres of Thailand. Although construction of the complex started in the mid 1990s, the smelter, acid plant and refinery were completed in 2004. Thai Copper is a state-of-the-art copper smelter processing imported concentrates with a total yearly capacity of 165,000 tonnes of cathodes. It employs the El Teniente Technology where concentrates are blended and smelted continuously in a primary smelting reactor to produce high grade matte or white metal. The white metal is converted in batches to blister copper in Hoboken siphon converters equipped with Air Liquide Shrouded Injector (ALS I) Technology for sonic injection of oxygen enriched air. Final refining is carried out in two anode furnaces prior to anode casting and electrorefining. Thai Copper and Air Liquide Canada executed a technical assistance agreement in late 2005. Pre-commissioning of the shrouded injectors took place in July and November 2006 while hot commissioning occurred in December 2006. This paper presents the major technical aspects of the joint commissioning, including the establishment of operating practices specific to shrouded injection converting. Preliminary results of this first commercial implementation of ALSI Technology in copper converting are also provided.

Jan 1, 2007

By Kimiz Dalkir

Some things to keep in mind? ! What is your role in knowledge management? ! What knowledge-related challenges are you facing today? ! How does important knowledge get shared in your organization? ! Can you name factors that enable/block innovation and organizational learning in your work context? A brief history of KM? ! Top-down / imposed ! Rigid / bureaucratic ! Slow deployments ! Expensive ! Unpopular: empty libraries, info-junkyards, low adoption rates ! Problems measuring success ! The result: traditional KM is not the answer

May 1, 2003

By G. Begin

"The expansion undertaken at Selbaie in 1985 necessitated an adaptation and expansion of the equipment maintenance system. This paper relates briefly the stages of transformation of the maintenance administrative structures, work methods and tools. The maintenance in a mechanized mine requires an expenditure level in the order of 20% of the total operating cost of the enterprise. Thus, the maintenance organization was modified to apply more computerized planning and follow-up, and the role of preventative maintenance was further advanced.IntroductionAs far as maintenance is concerned at Selbaie, the scenario described herein is a resume of the current situation. Although positive results have been obtained, this outline is in no way a detailed account of a fail-proof maintenance system.Once zone A-I was put into production, the expansion the mine experienced in 1985 had a direct impact on the equipment maintenance system. As centralized as it was in the beginning, the system is now partially decentralized.The over-all changes to the maintenance department demonstrate the flexibility required by organizations in new situations. In spite of the exceptional results obtained before the expansion, it became evident that both the maintenance and production sectors would have to be combined. In doing so, a more appropriate coordination of maintenance work could be obtained and the maintenance staff would obtain a more detailed knowledge of the equipment in each sector. In addition, by keeping the general and specialized departments centralized, it was possible to offset the negative effect s of a decentralized system, namely too much manpower."

Jan 1, 1990

By Barbara Kirby

Mining Industry Human Resource Council Who we are: National Sector Council for the Minerals and Metals Sector 18-person Board of Directors Over 100 Industry Volunteers PPP - Funded by HRSDC and industry What we do: Identify national HR challenges and opportunities for the Canadian mining industry Create national solutions through collaboration, partnerships and Synergy

Oct 1, 2010