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By C. B. Webber, W. A. Grell

"Sherritt Gordon's Ruttan Mine is a copper-zinc operation located approximately 600 miles north-west of Winnipeg. Open pit mining began in 1973 at 10,000 Tpd., with a change over to underground mining in 1981 producing 7,500 Tpd. Ore is crushed to -3/4"" followed by rod and ball mill grinding (two ball mills in series), differential copper-zinc flotation, and dewatering. The copper and zinc concentrates are trucked 75 miles to Lynn Lake, where they are shipped by rail to the HBM&S smelter at Flin Flon.This paper describes a method used to predict the effect of grind particle size on metallurgical performance, as well as details on the copper and zinc metallurgical performance due to fine grinding in actual plant operation.Initial statistical studies on historical data (including ore source, head gr3de, grind, etc.) indicated that copper and zinc recoveries increased with fineness of grind, in the range of 50 to 65% -200 mesh.In order to extrapolate beyond 65% -200 mesh, and to develop expected nonlinear relations between grind, Cu concentrate grade, and recovery, the assays of screen fractions of copper concentrate and tailing were used to determin8 the relation between net smelter return (a function of grade and recovery) and grinding cost. The optimum economic grind would be that grind at which the net smelter return less grinding cost reached a maximum."

Jan 1, 1982

By R. J. Enright

Eight mines in canada and three in Australia were visited between September 1987 and Februacy 1988. All mines had encountered problems with sulphide dust explosions and had introduced defence mechanisms to prevent or limit the extent of these explosions. Techniques included dispersion of limestone by various methods, use of water foggers, placing of water and inert stenuning in blast holes, and removal of settled dust to prevent secondary explosions. The techniques were evaluated and it was concluded that certain practices should be modified or discontinued as they were of little value in preventing dust explosions.

May 11, 1988

By Concentrator Staff

"IntroductionA brief literature search will reveal that the information available concerning rod mills and ball mills is quite extensive. This type of equipment is used to treat every element from antimony to zinc. The size and capacity of individual mills, the number of units employed, and the configuration of the equipment within a concentrator add another dimension to the possible scope of this discussion. It would be impossible to treat this volume of material with any degree of thoroughness.It is the intention in this paper to describe the simplest and generally the most typical circuit wherein a single rod mill and ball mill operate in parallel. Some of the subject matter will not be entirely applicable to every installation. However the principles should be generally relevant to most applications.Typical Circuit DescriptionFigure 1 illustrates the arrangement of the equipment associated with a rod-ball mill circuit.Ore is extracted from a fine ore storage bin (1) the capacity of which is large enough to allow .continuous mill operation independently of the mine and crushing plant production schedules. A number of feeders (2) may be employed to control the flow of ore to one or more feeder conveyor belts (3). In larger tonnage operations several such conveyors are employed at least one of which will be equipped with a variable speed control to allow adjusting of the amount of feed reporting to the rod mill. A rod mill feed conveyor (4) accepts all of the ore from these feeder belts for ultimate transfer to the rod mill. This conveyor is normally equipped with a weightometer (5) to monitor the flow rate of ore to the rod mill and ultimately to allow control of this flow. Typically these conveyor belts would be equipped with feed deficiency switches which would give a remote alarm of the fact that no ore is present on the conveyor. The conveyor belts are protected by underspeed monitors which will provide a remote alarm and automatic shutdown of the conveyor in the C'.'~nt that belt slippage occurs. Finally the belts are protected by monitors which will alarm and shut down a belt if it is not running straight in the idlers."

Jan 1, 1989

By Paul J. Cascone

This paper will discuss the science behind the development of a unique gold alloy for dental prosthetic applications. The alloy (GOLDTECH BIO2000) contains 99.7% gold providing unquestioned biocompatibility and unsurpassed esthetics. The topics discussed are: (1) How the alloy meets the functional requirements of a porcelain-fused-to-metal dental alloy. (2) How the alloy color affects the esthetics of the restoration and why the color of gold is best. (3) Overcoming the intrinsic malleability of gold when grinding the alloy surface. (4) Preventing the oxide color from interfering with the alloy esthetics. (5) Attaining excellent porcelain adhesion. (6) How the design of the restoration allows for the production of single and multiple unit restorations. Gold 2003

Oct 1, 2003

By Francis Chachula, Niel Erasmus

"In 2002, Titanium Corporation Inc. focused its attention on the development of a process for the recovery of valuable heavy minerals, including zircon and titanium bearing minerals from oil sands froth treatment tailings. The development of a process flowsheet to recover the titanium and zircon minerals from the Athabasca oil sand tailings has evolved through many laboratory, bench and pilot scale iterations.Initial development work focused on so-called ‘beach sand’ material, which is tailings material deposited over a period of time close to the tailings pipe discharge. The derived process flowsheet primarily consisted of gravity concentration stages, which is typical of all mineral sands operations. Titanium Corporation’s business plan calls for the utilization of tailings directly from the tailings pipeline – the process developed around the beach material is therefore risky as it differs from the live tailings in a number of aspects, with the effects on the process unknown. Titanium Corporation successfully obtained an intermediate product through a ‘bulk sampling plant’ coupled directly to an Oil Sands operator’s froth treatment tailings pipeline, during the summer of 2005. Subsequent further processing of this material resulted in poor separation or concentration of the heavy minerals due to a number of reasons. A more effective process flowsheet had to be developed.The newly derived process is basically a marriage between mineral sands technology and oil sands technology that can economically concentrate and recover the heavy minerals and entails the incorporation of a flotation process that takes advantage of the entrained bitumen in the feed to separate the heavy mineral fraction from the quartz gangue This paper will describe the newly derived process as well as the successful results of a subsequent on-site concentrator pilot campaign completed during the 3rd Quarter of 2006."

Jan 1, 2008

By Gianni Bartolacci, Patrice Nadeau, Szatvanyi. Gerard, Carl Duchesne, Claude Chrétien

"Combustion is used throughout the mineral processing industry to produce steam in boilers, to dry concentrates in rotary dryers, and to apply heat treatments in pyrometallurgical furnaces. Tight combustion control is very important in latter type of furnace since the combustion conditions directly affect final ore quality. However, achieving tight combustion control is not straightforward since most of the flames encountered in industry are turbulent non-premixed flames, they are affected by several unmeasured disturbances and are often produced by burning several types of fuel simultaneously, some of them coming from other parts of the plant. A novel method is proposed in this paper to improve process and product quality control as well as to optimize the combustion conditions based on digital flame color images. Multivariate Image Analysis and Regression is to used extract the flame color characteristics from images to predict the solids discharge temperature of an industrial rotary kiln. It is shown that this method yield extremely good 10 minutes ahead forecast of the temperature and should lead to a substantial reduction in product quality variability as well as in fuel consumption.INTRODUCTIONFuel-fired furnaces are often used in the mineral processing industry for various purposes, such as for the production of steam (utility boiler), in conjunction with rotary dryers to dry mineral concentrates or in pyrometallurgical processes for induration, roasting, and so forth. These furnaces are necessary in the supply chain from the mine to the metals, but their operating costs are constantly rising due to the fluctuations in fuel prices. Moreover, these processes are now targeted by the Kyoto Protocol since they are energy intensive and they produce significant amounts of CO2 and other pollutants such CO, NOx and SO2. To achieve both a reduction in operating costs (i.e. fuel consumption) and in pollutant emissions while maintaining or improving product quality, one needs to have a very good control of the combustion process."

Jan 1, 2005

By B. McLaughlin

"The Penna shaft is the deepest single-lift shaft in North America. Agnico-Eagle started sinking the Penna shaft in 1995 with a hoisting plant capable of hoisting 1800 t/d from a 2240-m deep shaft. Exploration success at depth led to the replacement of the existing double drum hoist by another double drum hoist capable of hoisting 7000 t/d. The use of another double drum hoist, instead of a Blair multi-rope winder, to hoist 24.5 t skips was only made possible by lowering the safety factor.This paper describes recent experiences at Penna and in South Africa, and examines the possibility of extending the double drum hoisting system to a depth of 3 km. IntroductionThe original Penna production hoist was a 4.88 m (16 ft) diameter double drum and single clutch machine. Béliveau (1996) and Scott (1996) have described this hoisting plant. In 1998, a decision was made to increase mining capacity from 1800 t to 4500 t of ore per day from the shaft bottom. Final capacity had to include an allowance of 1800 t of waste per day for future capital projects. While daily capacity was to be 6300 t, it would, by taking into account the different rock densities, be equivalent to hoisting 7000 t of ore.The steps taken to lower the safety factor were presented by McLaughlin and Scott"

Jan 1, 2004

By A. A. Beland, R. J. Dawson, S. Shewchuk

"Shovel buckets, scraper blades, dipper teeth, mine car wheels and hammermills are examples of equipment which require routine maintenance due to abrasion. Service life can be extended by the use 0/hard/acing and buildup materials. Mining and milling applications are described and field welding procedures discussed.A high-stress abrasion test used to select hard/acing and buildup materials/or hammers in a hammermill is described in detail. Field tests of the selected alloys confirmed their performance, and maintenance records showed a significant saving in down time and cost.The relationship between the abrasion resistance of the alloys and their hardness, work hardening, composition and microstructure is summarized. IntroductionLarge volumes of ore are handled daily by the mining industry. The abrasive nature of most ores results in extensive wear to both handling and processing equipment. If such wear is neglected it may cause lost production time and also, in extreme cases, require the complete replacement of expensive equipment. The well-planned maintenance of components subject to abrasive wear by means of buildup materials and hard facing can result in substantial economic benefits. Such benefits can , however, only be realized through the correct choice of welding process, consumables and deposition methods available to maintenance personnel. Hardfacing MethodsHardfacing is applied by a variety of methods; the three most widely used being arc welding, oxyfuel gas and thermal spraying. Table 1 summarizes the major processes used within each method. Filler metals in the form of rod, wire or powder are necessary to fulfill the individual requirements of each process. The filler rods are available in the cast form or, in the case of ductile metals or alloys, as wrought rod or tube. All types are supplied bare or flux covered. Wire is supplied in two forms, drawn flux cored and drawn solid. Powder filler metals are available in many metals or alloys; they may be simple mechanical mixtures or prefused and atomized alloys made to a specific size range and shape for optimum results for each applicable process."

Jan 1, 1980

By F. J. Alcock

THE Magdalen islands have recently been attracting attention as a possible source of manganese. As early as 1880 small masses of manganese oxides were known to occur in the soil and at least one attempt was made to develop them. In 1939, after the outbreak of war, interest in the possibilities of the field was again aroused and during the winter of 1939-40 claims were taken up by two groups of Toronto interests. The islands also contain large quantities of gypsum. During the summer of 1940, the writer mapped the islands geologically, giving particular attention to a study of the manganese occurrences. For a base-map, the chart of the islands was enlarged to a scale of half a mile to an inch. Additional roads were added from traverses carried out in connection with the geological work, and form lines with approximate 100-foot intervals were put on from barometer readings. The geological map is the first that has been prepared of the islands. Previous Work In the summer of 1880, James Richardson of the Geological Survey of Canada studied the rocks of the islands and his r~port concerning them appears as Part G of the Report of Progress, 1879-80. In 1903, J. Obalski, Inspector of Mines for the Department of Lands, Mines and Fisheries of the Province of Quebec, visited the islands, chiefly to investigate the occurrences of manganese and gypsum, and his notes are found in the report on mining operations in the Province for that year. Around 1890, Robert Chalmers of the Geological Survey paid a visit to the islands, and his observations, which chiefly concerned the surface geology, appear in the Annual Report of the Survey, Vol. VII, 1894, Part M, p. 94. The next geological work was carried out by John M. Clarke, Director of the New York State Geological Survey. Clarke paid many visits to Gaspé peninsula between the years 1900 and 1920, collecting fossils and gathering h1s~orical data, and extended his investigations of Gaspé county over to the Magdalens. His Observations on the Magda/en Islands is included in the New York State Museum Bulletin 149, seventh report of the Director, 1910.

Jan 1, 1941

By K. Meyer

"INTRODUCTIONThe David Bell Mine Concentrator started production in April 1985. A staff of twenty-seven people operate and maintain the concentrator. The crew is grouped into the following main areas.16 Operators6 Assaying/Metallurgy/Refining/Clerical4 Maintenance people2 SupervisionOperating highlights of the following unit processes will be discussed in detail:Screening and ThickeningPre-aeration and CyanidationCarbon-In-Pulp Gold AdsorptionCarbon Handling andGold RecoveryFor a complete description of the concentrator, refer to the papers by: (1) C.V. Sibbald, Teck-Corona's Hemlo Mill, October 1984, (2) R.A. Ford, The David Bell Mine at Hemlo, From Exploration to Production, November 1987. For operating details of the grinding circuit and effluent treatment plant refer to papers by: (3) T.G. Smith, SAG Mill Experience at The David Bell Mine, October 1988, ( 4) AN. Veltmeyer, The Effluent Treatment Plant of The David Bell Mine, January 1989.TRASH AND CARBON SCREENSTrash ScreenThe vibrating trash screen is inclined at 5 degrees and is clad with a 28 mesh stainless steel cloth which is changed monthly during the SAG mill liner replacement/inspection shut down. Other screen openings and configurations have been tried and the screen has been by-passed to change the cloth ""on the fly"". These attempts resulted in fibres (usually wood) to report to #1 Carbon-In-Pulp (CIP) tank, where the fibres are trapped in the CIP launder screens, and downstream carbon handling screens causing serious blinding problems. The trash screen in a Carbon-In-Pulp (CIP) or Carbon-In-Leach (CIL) gold mill removes fibres before they:are reground in the ball millsaturate with gold bearing leach solutionplug launder screens in CIP or CIL tanksplug carbon circuit pipe screenstherefore the trash screen is best placed ahead of the thickener."

Jan 1, 1989

By C. J. Brown

Controlling the level of impurities in copper refinery electrolytes is essential to achieving acceptable cathode purity. Purge of electrolyte is not an entirely satisfactory solution since the cost of neutralization, waste disposal, and replacement acid can be appreciable. The APU® process utilizes ion exchange resin to sorb sulphuric acid while rejecting metal salt impurities. Extensively employed for recovery of waste pickling and anodizing acids since 1977, the system is now being used at several refineries for removal of contaminants such as antimony, bismuth, iron, and nickel. The purified acid, which is recovered from the resin by water elution, is recycled back to the refinery tank-house, while the metals are typically recovered from the de-acidified by-product solution by precipitation.

Jan 1, 2005

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 K. Loutet, A. Guenkel, K. Nikolaisen

"The INCO SO2/air process was patented by INCO in 1985. Well over 80 mining operations worldwide are using this process to oxidize cyanides to cyanates in the tailings from gold, silver and copper mining operations. The sulphur dioxide (SO2) for this process can be supplied either as liquid SO2, SO2 gas or as a sulphite-based salt. The majority of SO2/air operations have used sulphite-based salts as the ‘SO2’ equivalent probably due to low capital cost. Liquid SO2 has also been used frequently, but due to concerns with safety and availability, this option is often not preferred. The solid salt sodium meta-bisulphite (SMBS) is commonly employed, but its cost is an order of magnitude higher than that of sulphur. Due to the high cost of SMBS, the increased capital cost for a sulphur-burning SO2 gas plant (green field or retrofit) usually has a pay-back of less than three years. In addition, a SO2 gas plant offers potential for significant heat recovery from the sulphur burning process. In terms of safety, the SO2 gas plant only requires the storage of relatively benign sulphur and the site inventory of SO2 will be limited to the plant gas volume. Therefore, a SO2 gas plant will not trigger the Canadian Environmental Protection Act (CEPA) E2 Regulations or the US Clean Air Act Section 112(r) accident prevention regulations, as may be the case for liquid SO2.Most existing mining operations using ‘SO2’ are gold operations, but in recent years there has been an increased interest in larger sulphur dioxide gas plants for hydrometallurgical facilities that employ leaching of cobalt/manganese minerals or precipitation of manganese/iron (e.g. Tenke Fungurume and El Boleo).This paper focuses on the production of sulphur dioxide gas generated on site and on demand for the use in hydrometallurgical processes. The capital and operational costs of a SO2 gas plant is compared to conventional process alternatives using sulphite-based salts or liquid SO2."

Jan 1, 2016

By R. H. O. Wagner

"This paper describes the bench testing, pilot plant studies of alternative flowsheets, to determine the feasibility of gold recovery, by carbon in pulp extraction, in the Schumacher Mill gold flotation tailings. The economics were calculated based on pilot plant recoveries and actual industry operating costs.The economics of the carbon in pulp treatment of the gold flotation tailings were not justifiable. The economics of desliming the gold flotation tailings followed by carbon in pulp treatment were marginal, but favourable. INTRODUCTIONPamour Porcupine Mines, Limited is a gold, silver and copper producer located in Timmins, Ontario. In 1983 the head grade of Pamour's gold ores averaged nine one hundredths of a troy ounce of gold per short ton.Pamour operates two area mills to concentrate the gold ores. Free milling gold ores are processed at the Pamour One Mine mill, whereas the refractory carbonaceous gold ores, and complex gold, silver, and copper sulphide ores, are processed through the Schumacher Mine mill.The complex Schumacher mill feed ores do not all react favourably to flotation methods, consequently this study was commissioned to investigate the feasibility of the carbon in pulp cyanidation of the Schumacher mill gold flotation tailings. These tailings contain ten to fifteen percent of the gold in the mill feed. During the study period, the average grade of the Schumacher mill flotation tailings was nine one thousandths of a troy ounce of gold per ton, or one quarter of a gram of gold per metric tonne."

Jan 1, 1984

By Iann Bouchard

Introduction à l?abrasion et l?érosion Avec le temps, tout solide va éroder et user les métaux les plus durs; de plus, la Corrosion va aussi laisser une couche mince et faible d?oxydation qui sera rayée du substrat. Solutions et guide de sélection Les polymères de Henkel Loctite® peuvent: ? Réduire l?abrasion par glissement ? Protège contre les agents corrosifs ? Prévenir la cavitation ? Augmenter l?efficacité ? Réduire la turbulence ? Résister aux hautes températures?

Feb 1, 2008

By Louis Cabot

A pilot plant of the Modular Gold Processing Unit (MGPU) was designed, installed and operated, over a 8 months period, by RSW-Béroma, at the Granada Mine located near Rouyn-Noranda, Quebec. A description of the project geology, plant set up as well as exploitation results, including productivity and profitability curves, are given for a small scale mining operation in comparison with larger ones. Copyright ã 2001 CIM

May 1, 2001

? Founded In 1953 ? Mining growth of 83% since 2007 ? We produced over 1 million ounces of Au in 2012 ? We Forecast of 20% Au production in 2013-2015 ? We have paid a dividend 31 years consecutively. Terry Reid ? 1992-93 Electrical Technical, College ? 1994-95 On the job placement College ? 1998 ? Licensed Millwright, ? 2005-12 ? Maintenance Reliability Planner ? 2012- Present Business Process Owner

Aug 1, 2013

By I. S. Thompson

"Exploration properties form a continuum from grass roots to those with favourable geology, geochemical and/or geophysical anomalies, mineralization, showings (prospects), and finally to those with defined mineral deposits. Often, properties exhibit a composite of these categories.The most problematic to value are properties or deposits that are not economically exploitable at the time of the valuation due to a lack of exploration, insufficient grade or tonnage, poor mining conditions, or the imposition of socio-economic, environmental, or legal constraints.Various acceptable methods of valuing the range of all such mineral properties or deposits are reviewed. Some less appropriate methods are also discussed."

Jan 1, 2002

By J. E. Sepulveda, R. Morrow

"The Linear Wear Theory provides a reliable framework for the assessment of grinding media performance at full scale. This theory can be applied for analyzing grinding media consumption rates in any given grinding operation as well as the evaluation of alternative grinding media products, based on actual operational data, correcting for conditions like ore hardness, feed and product sizes, mill power and circuit throughput; all of them unrelated to the grinding media intrinsic quality attributes. A series of Moly-Cop Tools 3.0 applications have been developed to facilitate the calculations involved. Moly-Cop Tools 3.0 is available, free of charge, to all interested parties through the corresponding author.INTRODUCTION Mineral grinding circuit operators recognize the significance of grinding media (balls) consumption on the cost structure of any full scale grinding facility. The effective cost associated with this essential consumable depends on two factors: delivered price and durability (quality) of the grinding media. When evaluating alternative grinding media varieties, there is a well accepted evaluation criterion by which a given media type is considered to be “cost-effective” when its unit application cost – normally expressed in $/ton of ore ground – is shown to be lower than that of a nominal reference condition: Grinding Media Cost = Ball Price x Ball Consumption (1) ($ /ton ground) ($/ton balls) (ton balls/ton ground) Under this criterion, an alternative, higher-price grinding media product could be “cost-effective” if its associated consumption rate is sufficiently lower than the reference media, enough to yield a lower grinding cost, as dictated by Equation 1. For the proper application of the above criterion, evaluators must rely on representative indicators of grinding media quality, ideally independent of most mill operating conditions. In each particular case, ball price is always a known component; however, it is not so evident how media performance (quality) differences amongst alternative product types could be assessed with a reasonable degree of accuracy and precision."

Jan 1, 2014

By Mario Bergeron

L'exploration géologique pour les EOP (EOP: platine, palladium, iridium, osmium, ruthénium, rhodium) requiert avant tout des méthodes appropriees à la mesure de ces élémenIs. L'approche analytique choisie doit tenir compte de plusieurs facteurs, les plus importants étant: le type de materiel analysé, sa representativite, la sensibitite de la methode et les cotits reliés à son utilisation. Dans cette optique, plusieurs démarches ana/ytiquessont possibles, toutes requérant une étape de préconcentration. L 'une des plus adéquate consiste à effectuer une préconcentration par fusion plombeuse suivie d'une analyse par émission au plasma, cette procédure permettant de mesurer Ie platine, la palladium et Ie rhodium à des couts compétitifs (15 $/échantillon). Advenant 10 presence de teneurs appréciables de l'un ou plusieurs de ces éléments, une préconcentration par fusion au sulfure de nickel suivie d 'une analyse par activation neutronique assure alors la mesure de tous les EGP ainsi que celie de l’or (90 $/échantillon). Il est important de noter que Ie nickel, ades teneurs superieures à 4%, interfère au cours de l'étape de préconcentration par fusion plombeuse, ce qui se traduit pas sous-dosage des concentrations en platine, effectivement presentes dans l'échantillon. Ainsi, les géologues à la recherche d'EPG dans des environnements géologiques riches en nickel devraient s'assurer que l'analyse utilise, au cours de l'étape de préconcentration, une fusion au sulfure de nickel.

Jan 1, 1990