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By R. V. Ramani

"A computer simulation model of a dragline has beer developed for the study of alternative dragline deployment schemes for varying geological and mining conditions. In this paper, the mathematical aspects of the model, the input data and output results are discussed. An application of the model to a coal mine in eastern Kentucky is presented.IntroductionDraglines are very productive machines. To extend their operating ranges, they are operated in several modes such as advance benching, key cut, extended benching and pullback. Unfortunately, these variations result in low machine productivities. Appropriate methods to operate these machines must be developed on the basis of detailed analyses of dragline performance under varying geological and mining conditions. There are several standard engineering procedures for the selection of dragline, and design of a dragline pit (Ramani, Iroegbu and Manula, 1976). However, the complex interrelationship which exists among equipment, methods and natural conditions can be quantified only through orderly and systematic experiments.Computer simulation is well suited to studying these types of equipment selection and method layout problems. Several alternatives can be analyzed in a relatively short time by the modification of input variables. Also, the application of computer simulation models can significantly reduce the manpower and cost required for such analysis."

Jan 1, 1985

By L. J. Heaslip, J. M. Toguri, T. R. Meadowcroft, R. L. Addinall

"""Pilot Plant Operations"" is a final-year core course given to the Metallurgy and Materials Science students at the University of Toronto. This course involves a laboratory study of an industrial project at an industrial site. Details of this program are discussed and reviewed after eight years of experience. IntroductionEducators in the field of Metallurgy and Materials Science have long agreed that ""hands-on"" experience is an important component in the education of metallurgical engineers. This philosophy is reflected in the undergraduate curricula of most metallurgical schools. The major problems encountered with laboratory-associated courses are the requirements for equipment, space and funds for both purchase and maintenance of equipment. For example, consider an exercise in crushing and grinding treatment in a mineral processing laboratory. Such operations require the handling of tons of material and often equipment of large size. The problems of storage of ore, methods of handling and maintenance of equipment are a few of the concerns facing the department. Considering that metallurgical departments at universities are, in general, relatively small, the support to purchase and maintain largescale equipment becomes an annual budgetary concern. In reality, universities today are not geared to operate mini-pilot plant equipment, either in terms of space or personnel.For the above reasons, in 1972an undergraduate core course called ""Pilot Plant Operations"" was introduced to the fourth year curriculum in Metallurgy and Materials Science at the University of Toronto. This course consists of I to 2 full weeks (8 hrs per day) of pilot plant laboratory study at an industrial site on a project of mutual interest with the industrial organization whose facility is being used. The first 5 years of the program were carried out at the pilot plant facility at the Ontario Research Foundation; Stelco's Research Centre in Burlington, Ontario, was used for the last 3 years. The nature of the projects undertaken during the 8-year period is shown in Table 1."

Jan 1, 1980

By Rees J. Llewellyn

High chromium white irons can be formulated to provide required combinations of abrasion and erosion wear resistance, toughness and capability to withstand corrosion attack. As a consequence, they are used widely in casting form throughout the mining/mineral processing industry, particularly as components for slurry pumps and also as mill and crusher liners, laminated wear plates in chutes and hoppers and in valves, nozzles and cyclones. Traditional cast chromium molybdenum and high chromium white irons for wear applications are covered in ASTM A532 Classes 11 and 111 and are also available as comparable proprietary alloys. They rely on heat-treated, hypoeutectic microstructures containing a high volume fraction of very hard eutectic/secondary metal carbides and martensite to provide extremely high wear resistance. The ability to increase the carbide volume fraction and hence achieve higher wear resistance, has been limited because of severe casting difficulties encountered when carbon and chromium contents are raised and hypereutectic alloys with structures also containing coarse acicular primary metal carbides are produced. The limitation has been overcome and cast hypereutectic chromium white iron pump components have established themselves in a wide variety of mineral processing service applications. Comparisons will be made between the microstructures and wear test performance data for the various alloy types and details will be provided of the service performance improvements that have been achieved through the use of hypereutectic chromium white irons.

May 1, 2004

By Theophile S. Yameogo

Les ressources naturelles ont en général été le moteur du développement économique et social des nations. Les pays aujourd?hui développés sont pour la plupart d?anciens eldorado, charbonniers ou pétroliers. D?autres le sont toujours. L?Afrique fait cependant figure d?exception : même en étant comblé de ressources naturelles exceptionnelles, les pays de ce continent croulent sous le poids de la pauvreté et de ses acabits que sont les maladies, la famine, la guerre et l?insurrection sociale. On reconnaît néanmoins qu?il y a des cas particuliers comme le Botswana, la Namibie, l?Afrique du Sud. Face à cette situation, beaucoup de scénarii ont été proposés sans pour autant porté les fruits espérés. Le rapport Brundtland suggère que le développement durable est la clé du succès car elle veille à la prospérité économique, à l?équité dans la société et à la pérennité dans l?environnement. Pour l?Afrique, beaucoup de facteurs doivent être considérés et les solutions se doivent d?être pratiques et éthiques. Le futur ingénieur des mines qui a écrit ce rapport, apporte sa vision de la situation non sans avoir auparavant analysé les faits. Cette démarche, qui se veut avant tout éthique, inclut les aspects sociaux, économiques et politiques. Introduction In the 40s, 50s and the 60s, many economists, among which Harold Hotelling from South Carolina University, thought that developing countries could reach socio-economical success by extracting their natural resources such as oil and minerals. The current economical disaster seems to have contradicted that belief and critics like Davis Graham (Colorado School of Mines) and Michael Ross (University of California at Los Angeles) even suggested that extractive activities stop in Africa. But the experts of the World Bank (Mining Department) and some mining and oil companies are committed to reverse the tendency by implementing a new approach. Considering the principles of sustainable development defined in the Brundtland report (1987), we decided to analyze the possibility of giving the extractive industry a catalytic role in creating a socially, economically and environmentally development in Africa. In other words, can we continue to mine and extract oil in Africa for its blossoming future under the ruling of the sustainable development? In the following, we start by explaining the African socio-economic and political context. After a brief definition of the sustainable development, we explain why, for Africa, some believe in the extractive industry and some don?t. In the end, we draw out conciliatory arguments.

Apr 1, 2005

By A. Akerman, C. P. O’Connor, N. Vayenas

"Stereolithography is a well-known rapid prototyping technique in the manufacturing sector. Essentially, it is a three-dimensional printing process that produces plastic prototype parts from standard CAD files. At present, Canadian mining companies are not fully aware of the potential of rapid prototyping techniques (RPTs) for their production and mine design systems. Mining engineers and geologists attempt to visualize and understand the characteristics and layouts of orebodies on computer models, and in cases where it is decided to develop physical models, the process is time-consuming, based on simplified constructions. RPTs, such as stereolithography, can facilitate engineers and geologists to quickly, and with satisfactory accuracy, visualize sections of orebodies and evaluate alternative ore extraction techniques using 3D solid models.The research discussed in this paper is carried out by the Laurentian University Mining Automation Laboratory (LUMAL) in collaboration with Inco Limited and the Integrated Manufacturing Technologies Institute (IMTI) of the National Research Council of Canada. The main objective with this research is to evaluate the applicability of state-of-the-art RPTs to underground hard rock mining systems. RPTs can play a significant role in accelerating the design and development process of mining systems."

Jan 1, 2006

By S. Fuentes, J. Cáceres

"During the past fifteen years, mines utilizing the block caving method have improved performance and systematically reduced total mining costs.This paper describes improvements in mine design, mine planning, and mine management, including methods enabling the Chilean and international mining industry to ensure cost savings and productivity growth while using the block caving method. These improvements have encouraged the re-evaluation of underground operations at operating and closed open pits, and challenge surface mining applications as the only low-cost mining method. This paper describes a strategy to estimate the optimum open pit to underground transition time during the life of a mine. IntroductionDuring the last fifteen years, block caving mines have experienced huge changes in designs, planning and administration. These changes have permitted operators to drastically reduce costs, improve equipment productivity, and improve overall business performance. As a consequence of this situation, the block/panel caving mining system is challenging actual open pit operations to maximize the net present value (NPV)."

Jan 1, 2004

By Daniel Hodouin, Claude Bazin

"This paper examines the economic advantages of tuning the operation of a differential Cu-Zn flotation circuit as a function of metal prices. Three operating strategies are considered in the analysis: 1) the operation of the circuit at planned copper and zinc concentrates grade with maximum recovery of both metals; 2) the operation of the Cu circuit at maximum copper smelter return per ton of ore and of the Zn circuit at a maximum zinc smelter return per ton of ore; and 3) the operation of the circuit at maximum copper and zinc smelter return per ton of ore. The second strategy tunes the copper circuit independently from the zinc circuit, while the third strategy tunes both circuits simultaneously IntroductionMetal prices play a very important role in the mineral industry (Malhotra and Dowling, 1991). In many cases, metal prices can be the basis for the GO/NO GO decision of a mining project (Malhotra and Dowling, 1991; Apostolides, 1983; Davis, 1996). This direct impact of metal prices on company revenues is highlighted in many annual reports. The 1995 Noranda Annual Report indicates that a variation of 10% of the copper price impacts its yearly revenues by $25,000,000. Some mine operators claim to mine stopes as a function of metal prices (Liimatainen, 1996; Hartman, 1992). This impact of metal prices is also recognized by mill operators that seek strategies to tune ore processing circuits to maximize revenues from the concentrate they sell to smelters (McKee, 1991; Barker et al., 1989; Hales and Ynchausti, 1994; Cipriano et al., 1995). In many cases the problem of tuning the operation of an ore processing circuit is complicated by the fact that the ore contains two or more valuable metals which have to be recovered into separate products. The Agnico-Eagle (Robitaille and Cousin, 1995) and Barrick East Malartic (Pelletier, 1996) Cu-Au mines are examples, as well as the Cu-Pb-Zn Brunswick mine (Shannon et al., 1993) or the Cu-Zn Louvicourt (Whiteway, 1995) and Selbaie (Wright, 1995) mines."

Jan 1, 2000

By G. Hausen, H. Micka

"Modern signal and power electronics made adjustable-speed AC drives technically feasible and reliable and economically attractive. Cycloconverters are discussed as a proven technology for mine hoists. \IntroductionUntil rather recent technical and commercial advances in power and signal electronics, DC motors were used almost exclusively for applications requiring continuously adjustable operating speeds and torques. More recently, the significantly higher efficiency and the accordingly lower operating costs of AC motors gained importance. An effective and efficient speed control of AC motors requires the control of AC voltage and frequency. Table 1 shows typical applications of adjustable-speed AC drives.CycloconvertersOf particular interest to the mining industry are cycloconverters for hoist drives. The cycloconverter represents by far the simplest, most efficient and most economical means of converting a constant-voltage, constant-frequency supply into an adjustable-voltage, adjustable-frequency supply as required for the speed control of AC drives operating in the frequency range to half of the utility frequency.Cycloconverters feeding synchronous motors or induction motors are ideally suited for slow-speed direct-coupled drives."

Jan 1, 1988

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 Abdelkabir Maqsoud

Different management options and rehabilitation strategies are available for mine wastes that produce acid mine drainage (AMD). One of them consists in building a cover with capillary barrier effects (CCBE) on the tailings to limit the availability of oxygen, an essential component of the chemical reactions leading to the generation of AMD. Prior to cover construction, a monitoring strategy must be established to evaluate the response and performance of the cover system. The key parameters to monitor should include matric suction and volumetric water content in the CCBE, oxygen flux (and/or oxygen concentration) through and below the cover, and the main meteorological parameters for the impoundment. In this paper, different techniques available to measure the targeted parameters are described and their main properties are given. Recommendations (based on existing cases) on the location and the number of monitoring stations and on the measurement frequency for each monitored parameter are also proposed.

May 1, 2007

PERSPECTIVE ?Natural resources exploration, extraction and beneficiation is complex and challenging: ?Input costs rising, complexity increasing, rising stakeholder management needs, regulatory compliance issue, etc. ?With increasing costs and complexity of managing operations are we simply getting less bang for our buck?

May 1, 2013

By H. M. Lewis

The current status of the international zinc market is summarized, and a supply /demand outlook is presented for the next five years. A number of technical problems facing the industry are outlined. Introduction ZINC has sometimes been called the unknown metal. Considering that on a world basis it ranks third among non-ferrous metals in production and consumption, zinc retains a certain modesty. It has no distinctive colour like copper, lacks the low density of aluminum or magnesium and is not always easy to identify as a product. The 'spangle' of galvanized steel is probably zinc's most distinguishing feature. The purpose of this article is to develop an over-all review of zinc. Starting with the current position of the metal, the major factors that will shape its future will be described so that an assessment of the outlook for zinc can be made.

Jan 1, 1978

By G. A. Kosick, C. A. Harris

"Metallurgy at the Polaris Mine is approaching an impasse, with lead and zinc concentrate grades and recoveries approaching their theoretical maximums. In an effort to increase productivity, plant throughput and operating material costs became a major focus of milling personnel.one method of increasing plant throughput was to minimize flotation circuit upsets by; standardizing operating strategy, decreasing control action response time of operators, increasing training of operators, and providing a more available decision support system for operators.To achieve these goals, Polaris personnel decided to utilize expert system technology to develop a real-time process controller for the flotation circuit which would be capable of justifying its actions to operating personnel.This paper describes the procedures followed in constructing the first process controller in the mineral industry which is based on the principles of Artificial Intelligence.IntroductionThe Polaris Concentrator was constructed in 1980 on a barge in Trois Rivieres, Quebec and towed to its present location on Little Cornwallis Island, North West Territories, about 1450 kilometers from the North Pole. The plant presently treats about 2,800 MTPD of new feed with average feed grades of 3% Pb, 13% Zn and 5% Fe. Current production averages 36,000 tonnes of lead concentrate and 220,000 tonnes of zinc concentrate annually.In an effort to increase the efficiency of the concentrator, the decision was made to implement an innovative control system on the flotation circuit. This system would embody and utilize heuristics ""rules-of-thumb"" gained from operators to make on-line process decisions. It would also justify these decisions on a demand basis."

Jan 1, 1988

By Syamujulu. M

Subsequent to the unbundling of the Zambia Consolidated Copper Mines (ZCCM) and the privatization of its constituent parts, the Konkola Copper Mines (KCM) represents a third of the original conglomerate. Now run by private hands as a sub group of Vedanta Resources Plc of India, KCM is strategizing on how best to deal with the operational issues of the organisation to resolve some of the difficult, logistical, environmental, mineralogical and metallurgical problems being encountered to tum them into opportunities as the company turns around. This paper reviews the options being put in place to provide appropriate solutions and strategies including the treatment of the highly siliceous low energy copper belt concentrates in its mining operations in Zambia.

Jan 1, 2007

By Terry Keough

Contents for discussion ?Current liner technology ?Innovation of magnetic products ?Development of magnetic wear liners ?Installation and change out method ?Uses and capabilities ?Internal wear liners ?Summary Vulcanized rubber ?Many of you are familiar with using vulcanized rubber to provide wear protection on mining equipment. For years, this was the standard for most mining equipment, and mines spent a lot of money fabricating and lining steel equipment.

May 1, 2010

By K. G. Chipman

IN 1936, the Department of Mines and Resources was formed by the amalgamation of the former Departments of Mines, Interior, Indian Affairs, and Immigration. In the amalgamation, the Geological Survey and the Topographical Survey became the major divisions of the Bureau of Geology and Topography, which is a part of the Mines and Geology Branch which, in turn, is a part of the Department of Mines and Resources. The Topographical Survey was formed by combining the former Topographical Division of the Geological Survey and the air and ground mapping sections of the former Topographical and Air Survey Bureau of the Department of the Interior. The latter organization, previous to 1933, had been known as the Topographical Surveys Branch of the Department of the Interior. The amalgamation of 1936 definitely placed on the Topographical Survey the responsibility for the original mapping required for the development of our natural resources. The war has brought upon us the situation where all work has had to be in the furtherance of the war effort. With decreased staff and limited appropriations, the mapping on those scales which are directly concerned with the natural resources has been confined to the search for oil and strategic minerals. The reconstruction period will produce a different situation, with different problems. The past is behind us and it is necessary to prepare for the future. First, we should consider briefly a few general principles in the making and using of maps, then take stock of what we have, see what the needs are, and consider how we are to meet these needs.

Jan 1, 1944

By R. Hamilton

"Louvicourt mine began operation in 1994. It is located in northwestern Quebec, 20 km east of Val d’Or. The mine is owned by Aur Resources (30%), which operates the mine, Teck/Cominco (25%) and Novicourt (45%). By the end of 2002 there were approximately 280 employees working on the site, including contractors. Production averages 4300 tons per day, working a massive sulphide body located between 415 m and 920 m underground.Maintenance expenses represent 27% to 29% of the operating costs, and the maintenance personnel represents 34% of the total workforce (including electrical, mechanical and concentrator maintenance staff). Considering these figures, in addition to capital costs and indirect costs, such as energy (electricity, fuel, gas, etc.), it is worthwhile to pay attention to how things are done in order to protect such investment. Every task performed to help understand the impact of Louvicourt’s practices must to be seen as an investment in the reliability of its operation."

Jan 1, 2003

By Hassan Ghaffari

? HPGR Process/Overview ? HPGR vs. SAG ? The Manufacturers ? Mine Operations using HPGR ? Projects by Wardrop/Tetra Tech ? Economic Benefits ? Questions Main Operating Parameters ? Press Force (N/mm2) ? Roll Speed (m/s) ? Moisture Content (%) ? Feed Particle Size Distribution Specific throughput M* = throughput/D*L*V (ts/hm3) Flake thickness/strength in balance with the compressing force (floating roll situation)

Aug 1, 2013

By Yves Breau, François Robichaud, Jacques McMullen, Pierre Pelletie

"The Expert System implemented at the East-Malartic mill controls a copper flotation circuit while taking into account the profitability of the operation. Treating a copper gold ore, the flow sheet integrates a flotation step followed by cyanide leach circuit. The Expert System calculates the actual net smelter revenue of the flotation circuit, accounts for the operating cost of the cyanidation circuit and defines optimal metallurgical operating targets to optimize the overall economics. To be realistic, probability factors and circuit diagnostic analysis are integrated in the operating target selection. The Expert System has proved to be successful, robust and flexible. It resulted in a copper concentrate grade increase of 1% while maintaining recovery. The use of the expert system also gives plant personnel good training procedures and promotes interaction with mill operator.INTRODUCTIONThe East-Malartic mill is located close to the town of Malartic in North Western Quebec, Canada. The mill was first commissioned in 1938. The flowsheet at that time was a straight cyanidation circuit. The original mill operated in that mode up to the discovery of the Bousquet 2 orebody in 1989 which consisted of a massive copper sulphide ore averaging 0.7% copper and 7 g/mt of gold. Bousquet 2 ore processing required a mill retrofit. Grinding capacity, gravity and copper flotation circuits were inserted prior to the cyanidation circuit in order to achieve 3,200 mtpd capacity at expected recoveries.In 1993, control of the flotation circuit was deemed critical in order to maintain the flotation performance and to reduce cyanide consumption since the copper sulphide contained in the Bousquet 2 ore is a high cyanide consumer (50% bornite). (McMullen, 1999) As a result, the implementation of advanced control strategies in order to increase the metallurgical profitability of the plant and to reduce the operating variability between operators was the most rational alternative. In 1994, Corem was chosen to perform the plant audit and to write the first set of rules. The on-line control strategy was started up in 1995. In 1996 and 1997 the Expert System was shutdown because of an extreme change in the ore coming from the milling of Bousquet #1 ore and the departure of the projects engineer. In 1998, the system was restarted and the results were impressive. Furthermore in May of 2001 a patent was issued for the control strategy. (Breau, 2001)"

Jan 1, 2002

?General Facts:Barrick?sFirst Mine in Peru Production started in November 1998 ?The Facilities:Open Pit, Primary and Secondary Crusher Valley Fill Heap Leach PadMerrill Crowe PlantRefinery Environmental Facts: High Rainfall - Average Annual Precipitation of 1,200 mm (47 inches) Rainfall Events: Common 20mm daily events High Altitude Site - Elevations range from 3900 to 4250m. Steep topography - Terrain ranges from 3:1 slopes up to cliffs. Water Issues: Sediment Control - Open Pit PAG Encapsulation - Waste Dump Stormwater control - Leach Pad Erosion Control Techniques ? Offsite impacts mitigation Social Issues: 11 communities surrounding the property Town of Huaraz

May 1, 2003