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Who is ArcelorMittal Mines Canada ?One of Canada's leading suppliers of iron ore to steel markets around the world ?Past company name = ??Quebec Cartier Mining?? ?Operator of one of North America's largest open-pit mines ?Mont Wright Mines ?Fire Lake Mine ?Largest ArcelorMittal iron ore mining subsidiary ?Annual production of 15 million tonnes of concentrate ?Major expansion program to 24 MT/Y ?Internationally competitive pellet plant ?9.0 million tonnes annually

May 1, 2011

By E. O. Magnusson

THE orebodies of the Preston East Dome mine show a considerable variation in size,? shape, dip, and ground condition. They vary from small and large irregular masses being mined by shrinkage, cut-and-fill, and square set-and-fill mining methods to narrow veins being mined by open stoping. Standardization of mining operations has necessarily been difficult. This considerable variation in mining condition prompted the development of a bonus system which would give more equitable bonus payments through-out the mine than those obtained by the usually accepted methods of calculating mine bonus. PRINCIPLES ON WHICH THE SYSTEM IS BASED Under an incentive bonus system, performance (efficiency) and a price per unit of work done are inter-related. It is in the application of this? principle to working conditions .in the Preston East Dome mine that the system to be described differs from the standard methods of calculating mine bonus. It was found that the method of paying a fixed price per unit of work done, under the 'contract' system, gave satisfactory results in development, less satisfactory results in timbering, and results which were not satisfactory in stoping. Under the fixed price system, bonus payments, in timbering and stoping particularly, were very erratic and did not necessarily represent fair payment for the work done. A fixed price in development is satisfactory because the work done, and the conditions under which the work is done, are uniform. The drilling and blasting cycle is completed in one shift, the size of heading is con-trolled, and a minimum number of holes are required in order to obtain a satisfactory break. The performance possible under these conditions has been found to be confined to a fairly narrow range. By performance in development is meant the efficiency of the working crew as expressed in terms of the two variables of feet of advance per round and pounds of ex-plosives consumed per foot of advance. A change in rock formation, how-ever, may alter to a marked degree the performance possible, quite independent of the skill and energy of the working crew. The changes in working conditions that affect development performance from the standpoint of bonus calculation are usually easily apparent and are satisfactorily met by establishing several fixed prices.

Jan 1, 1944

By Gerald Sanders

Presentation Topics ? We?re Going to the Moon Again? ? What is Lunar Mining ? In-Situ Resource Utilization? ? What Are The Challenges to Lunar Mining? ? What is NASA Currently Doing?

May 1, 2009

By W. W. Muir

"The Baker Mine used a 100-ton per day conventional cyanide leach mill located in northern British Columbia. A production decision was made in early 1980 and the mill was on fine in April 1981.Ore reserves had been estimated at 100,000 Ions averaging 0.9 oz gold per ton and 18 oz silver per ton . Mineralization consists of electrum (Au/Ag) and acanthite (Ag2S).This paper will review plant design and focus on some problems associated with start-up and early operation with the intention of assisting other mine operators by indicating potential problem areas.IntroductionThis paper will discuss operating strategies employed at Baker which improved over-all mill performance. Also included are some ideas which could be steps toward a more efficient operation in a similar setting.Actual dore production by mine life was 37,606 oz gold and 742,117 oz silver.Figure 1 illustrates the relative stability attained over the mine life. Metal recoveries for gold and silver were 92% and 85% respectively.Safety at Baker was of prime importance because of its remote location. Baker received the Mine Safety Association ""Small Mines Award "" in two of its three operating years. At shutdown in late 1983 the mill had operated for over 850 days without a lost-time accident."

Jan 1, 1985

By M. Gangal, M. Grenier, D. Mchaina, S. Hardcastle

"Exposure to airborne respirable silica in surface and underground mine operations is known to be the cause of industrial lung diseases. For this reason, silica is a regulated substance and worker exposure must be monitored regularly. Diesel exhaust also contains substances which are potential caricinogens. In an underground setting, diesel particulate may be the main component of what is referred to as respirable combustible dust (ReD). Although diesel particulate or soot is not at present a rigorously regulated substance, new epidemiological data is prompting North American institutes and agencies to regulate diesel soot or RCD exposure. This paper describes a method where by silicaand RCD exposure may be determined using a single personal sample. In this method, an airborne respirable dust sample is obtained and analyzed nondestructively for silica components using an on-filter X-ray diffraction method. Filters are then ashed at 500°C in a muffle furnace over a four-hour period to determine mass loss due to RCD burning. Using on-filter X-ray diffraction analysis as opposed to redeposition of dust samples onto another analytical substrate allows the"

Jan 1, 1992

By B. E. Jones

"The area of uranium deposition is situated within the Churchill Province on the western edge of the Wollaston Iithostructural domain where it underlies the eastern edge of the Helikian Athabasca Formation. The Collins Bay deposit is 6 miles north-northeast of the Rabbit Lake mine. Two principal zones of uranium mineralization are described.The ""A"" zone is a partly eroded, high-grade pod of metal oxide and arsenides sheathed by clay-like minerals. It trends north-northeast and lies under 25 to 40feet of water. Uranium mineralization is localized at or adjacent to the unconformity between the Athabasca Formation and the basement rocks. The basement comprises a granitoid Archean terrain overlain by paragneisses of the Aphebian Wollaston Group. ""A "" zone ore contains phyllosilicates, quartz, pitchblende, rammelsbergite, pararammelsbergite, carbonaceous material, galena, gersdorffite, niccolite, carbonate and a trace of sphalerite.The ""B "" zone lies 6,000 ft south of the ""A "", and subcrops under till cover. It is a partly eroded zone composed of metal oxide and arsenides which occur within variably altered Athabasca Formation. Minerals recognized are phyllosilicates, pitchblende, niccotite, gersdorffite, millerite, carbonaceous material, pyrrhotite, skutterudite and a trace of galena. The Athabasca Formation varies from 90 to 160ft thick. Granitoid gneisses of probable Archean age and paragneisses of the Wollaston Group underlie the deposit. An easterly dipping thrust fault transects its length.The deposit is typical of the ""unconformity-type"" uraniumnickel deposits of the Athabasca Basin. Observed features fit well with the ""diagenetic-hydrothermal"" model for such deposits, as envisioned by Hoeve and Sibbald (/978)."

Jan 1, 1980

By E. Henderson

"This paper outlines the upgrading of a double-drum 2000 hp cage hoist to provide fully-automatic operation from shaft station control panels. The application utilizes programmable controller technology to provide all necessary functions for movement of personnel and material to 22 locations in a 4000 ft shaft.Various functions involving special design considerations such as ""chairing"", ""jogging"", and three modes of ""multi-level calling service"", are outlined. The use of higher level PLC functions to optimize memory utilization and simulate ""elevator service"" required the addition of a comprehensive fault finding software section to aid in troubleshooting.This paper will deal primarily with the automation portion of the project with references made to other pertinent aspects which were prerequisite to automatic operation. It is not intended to deal with every design detail, but rather to provide an overview of what can be done in the area of automation for those considering such an application. INTRODUCTIONEarly hoisting control systems provided only the essential elements of control, leaving many responsibilities with the operator. With advancements in various areas of technology, electromechanical devices were incorporated to enforce slow-down in end zones, control acceleration rates, monitor safety devices, etc. Brake control systems were supplied to allow for ""single-stick"" operator control, regulated deceleration during emergency brake applications, etc.These additions enhanced the over-all performance but were generally confined to speed and current regulation. Some mechanical devices, such as travelling nut limits, etc.; were used to provide ""position"" control to multiple locations within the shaft. These devices, in conjunction with rather extensive relay control panels, did allow for the establislunent of some automatic cage hoists . The hoists were often limited to service from point ""A"" to point ""B""', involving a limited number of levels due to the complexities of the mechanical interfaces employed. Only limited systematic work sequences were possible . .Programmable Logic Controllers (PLCs) were introduced into industry in the mid-70s and have since gained acceptance in mining applications such as pumping, ventilation, ore handling, etc. This technology, being ""software"" based, allows complexities to reside in the program rather than increasing the number of physical control elements. This has opened the door into hoisting systems for automatic loading and hoisting of ore as well as a means to achieve a comprehensive package of automated cage hoisting functions."

Jan 1, 1989

By J. Elderton

"The combination of A C induction motor and flu id coupling, of either the fixed or variable filling type, constitutes a simple, low cost, highly reliable drive unit, with many applications in the mining field.The paper will, however, concentrate on the variable filling fluid coupling in three principal applications-conveyor starting, infinitely variable speed control for slurry and slimes pumping and dewatering pumps for deep mines. Fluid couplings can be used with standard or custom-built control gear equipment, ranging from the most simple, time-based open loop types, to those having the latest microprocessor techniques.IntroductionThe first industrial applications of fluid couplings included their use in the mining field as hydraulic slip regulators for flywheel generating sets. These installations, usually rated at around 1700 to 2500 hp, were located at mine shafts where the electrical grid transmission lines were not strong enough to cater for the peak power demands of the cage winding cycle. In Canada, the first two significant examples of variable filling fluid couplings for mining were on conveyor drives, at Steep Rock Mines Limited, closely followed by the major iron ore handling term inal on the St. Lawrence River at Sept-Iles. Successful and reliable operat ion of the fluid couplings at these two sites set the pattern for use on many subsequent mining projects throughout the Canadian Continent."

Jan 1, 1986

By R. D. Studer

"The Snow Lake massive sulphide deposits are hosted by Aphebian volcanic rocks of the Flin Flon - Snow Lake greenstone belt, which in this area were deformed and metamorphosed to the amphibolite facies during the Hudsonian orogeny. All the known deposits occur in felsic rocks a short distance below the contact with an overlying mafic rock unit.The Stall Lake copper deposit occurs close to the top of an explosive felsic volcanic sequence. Rocks stratigraphically underlying the deposit have been hydrothermally altered by the mineralizing fluids. The sulphides were probably deposited from submarine volcanic vent(s) on the flanks of a felsic dome. The ore has been tightly folded, flattened and elongated parallel to the northerly trending lineation of the surrounding rocks during the several periods of deformation. Strike lengths of the lenses range from 60 to 300 feet and plunge-to-strike ratios are as much as 15:1.Ore lenses 1 to 4 typically consist of massive coarse-grained pyrrhotite, chalcopyrite and pyrite. A stratigraphically higher lens differs in that it contains fine-grained pyrite and chalcopyrite, with an increase in sphalerite toward its hanging wall. The No.4 orebody has a distinct footwall alteration zone characterized by brecciation and abundant chlorite-staurolite-garnet schist, with minor kyanite, anthophyllite, cordieriteand anhydrite, as well as sulphide minerals. Chemically, the alteration zone is distinguished from the unaltered felsic rocks by Na20 depletion and Mg-Fe enrichment.IntroductionThe Stall Lake copper deposit is located aproximately 4 miles southeast of Snow Lake in northern Manitoba (Fig. 1). The Snow Lake district has been a producer of gold (Rex, Bingo, Laguana and Nor-Acme Mines) and, since the fifties, of copper and zinc from deposits of Hudson Bay Mining & Smelting Co., Ltd . The district is located near the eastern limit of the Flin Flon - Snow Lake greenstone belt, which contains Amisk metavolcanic rocks of Aphebian age."

Jan 1, 1982

By P. L. Lehoux, R. F. Lopes

"Unanticipated low recovery or extraction of gold from heap leachable are can often be attributed 10 phenomena such as non-uniform percolation (channelling) of solution through heaps, excessively slow percolation rates due to densification of ore during stacking on the pads and parasitic or competing reactions of the cyanide solution with undesirable elements or geochemical ""impurities"" in the ore. The nature and causes of these phenomena are discussed in this paper, and it is suggested that geotechnical and geochemical expertise can contribute significantly to a better understanding of the relationship between laboratory results and actual field performance of the leaching process. Recommendations are made for bench-scale metallurgical testing to be complemented by geochemical and geotechnical laboratory evaluations, to ensure more successful heap leach projects. IntroductionHeap leaching is a simple, low-cost method of recovering metals from low grade ores which has now come into widespread application particularly for gold and silver metals in the United States.The heap leach process involves percolating a lixiviant (leaching agent) solution through broken or crushed ore (Chamberlain and Pojar, 1984). In the case of gold a dilute sodium cyanide solution is used and crushed ore is ""heaped"" on specially prepared impervious pads.The potential for use of heaping leaching methods for northwestern Ontario gold deposits was discussed by Beard (1983), who suggested that the use of this extraction technique in Canada should grow significantly for low grade ores as well as for small high grade deposits which cannot justify the installation of a new mill or the use of remote custom milling facilities. Two other potential situations for lise of a heap leaching extraction method are : as a low capital cost cash generator in the opening phase of a larger new project, and as a low cost output augmenter to complement a milling operation."

Jan 1, 1989

By D. A. Mackie, J. E. Rider

"Good belt conveyor design is the most often neglected detail in the engineering of a plant. This results in downtime from spills or jams and premature failure of equipment components. Careful layout and component selection will result in better operation, a cleaner plant and therefore lower maintenance costs.IntroductionDespite the availability of many excellent sources of data on conveyor design, such as the Conveyor Equipment Manufacturers' Association (CEMA) Manual, ""Belt Convyors for Bulk Materials"" , there continues to be repetitive errors made in design. Why? Certainly, there is no substitute for experience, but largely, classical errors in belt conveyor design is rather elementary and so the temptation to have the work done by relatively inexperienced designers is great. What that does is develop "" experienced"" designers who become incompetent through no fault of their own. It is hoped that this paper will supplement available design data, help those who are "" put into"" a design situation to better cope with their predicament, and ease the lives of plant maintenance personnel."

Jan 1, 1990

By T. Yalcin

"This paper describes the development of a process flowsheet designed to provide high dewatering rates and to bring about savings in tailing disposal costs. The flowsheet comprises a hydrocyclone, a settling cone and a thickener arranged in closed circuit. The mill tailing, after pulp density adjustment, is fed to the hydrocyclone which yields two products. The underflow product is sent to the settling cone for further dewatering. The overflow product, together with the settling cone overflow, goes to the thickener which, with the aid of flocculants, gives a clear effluent and a relatively dilute underflow. The latter combines with the original mill tailing to form the hydrocyclone feed. Solids finally leave the system in the settling cone underflow which can reach pulp densities of up to 78%, making it suitable for direct disposal or for use as mine backfill.Some discussion is included for the selection and sizing of equipment required for this process. INTRODUCTIONDewatering is an essential process for the disposal of mill tailings which forms an added burden in milling practice, often with little or no return. It is, therefore, desirable to conduct this process as economically as possible. One way of reducing costs would be to increase the rate of dewatering so that savings can be made in the size of dewatering unit s which would lead to lower capital and operating expenditures.A common method of dewatering mill tailings is gravity sedimentation which is frequently carried out with the aid of flocculation. In most cases, flocculation greatly enhances the sedimentation process, but only until a pulp density of 50% to 55% is reached in the settled material.Centrifugal sedimentation in hydrocyclones can provide high pulp densities rapidly, but does not result in a clear effluent.This paper outlines a suitable combination of gravity and centrifugal sedimentations that results in an over-all high rate of dewatering. The system developed produces a material of high pulp density while at the same time giving clear effluent."

Jan 1, 1989

By J. J. Jonas

The categories of interpass time encountered in hot rolling are characterized. These are shown to fall into three broad categories: short (in rod rolling); intermediate (in strip processing); and long (in plate schedules). The effects of interpass time on recrystallization and carbonitride precipitation are described, and particularly on the interaction between these two mechanisms. The interactions, in turn, determine the final microstructure produced as well as the mechanical properties.

Jan 1, 2005

By H. R. Banks

IF you have ever travelled in the valley lying between the Selkirks and the Rockies in the East Koorenay district, you will have noted that the former mountains are rounded and massive, while the serrated peaks of the latter, fingering into the sky, bring an entirely different. picture. These two mountain ranges, with the comparatively level valley between, serve splendidly to introduce the subject for discussion. It is rather strange that, despite the fact that wear is undoubredly the greatest force with which human ingenuity bas to contend, it has come in for very little study from the stand point of pure science. Empiricism has been the sole ally in the fight for improvement! That we may have a clear understanding as to what we mean by wear, I would include in the term the breaking dawn of ail solid matter, from the natural wearing dawn of the mountains previously mentioned, to the hale in the mill pipe-line, which forces one to shut-down-usually at some un-earthly hour-to carry out a repair. It seems a far cry from mountains to mill launders or pipe-lines, but, magnified sufficiently, most of the materials with which we have to deal would show surfaces not unlike those we see around us. The progressive steps of wear, or ?erosion' as our geological friends would prefer to term it, are exemplified in the two ranges of mountains and the valley between. True, the wearing dawn by natural forces is a slow process. The aeons which have passed since first these mountains were formed seem endless. The natural forces pitted against them seem puny in the light of the interminable rime that has been needed to effect the changes. But here, as in the case of the materials with which we are dealing day by day, the combination of many forces ultimately brings about that condition which we describe as 'worn out'. In the case of the mountains, it is when they are finally levelled into plains, and in the case of equipment which we use, it is when that equipment will no longer serve its purpose.

Jan 1, 1943

By Juan Asalgado

The JORC and NI43-101 codes impose that mineralized material has a reasonable prospect of economical extraction to be classified as Mineral Resource. For deposits close to surface and amenable to open pit mining, it is easy to show reasonable prospect of economic extraction running a Lerch-Grossman optimization. The Lerch-Grossman pit provides a transparent and repeatable way of separating the Mineral Resource (within the pit) from the remainder of the mineral inventory (outside the pit). Deposits amenable to underground mining are more challenging because of the variety of the underground methods. AMEC developed a stand-alone software package that outlines the material which has reasonable prospect of economic extraction for open stoping, block caving, sublevel caving and room and pillar. The software takes a block model file in ASCII and exports a 3D surface outlining the part of the mineralization that has a reasonable prospect of economic extraction, and which the Qualified Person can smooth out manually if required.

Oct 1, 2009

By J. S. Stachulak

"IntroductionInco Limited operates nine underground mines on the rim of the Sudbury Basin. These operation s are situated near the city of Sudbury, 589 km west of Montreal, and 363 km north of Toronto. The ores are mined primarily for nickel and copper, and the principal minerals are pentlandite, chalcopyrite , and pyrrhotite. Total ore production from underground is in excess of 51 000 tons per day.The total volume of fresh air supplied to the nine mines is six million cu.ft/min. There are 50 main fans in operation at these mines, powered by electric motors totaling 11 200 kW (15 000 hp).The trend in metal mining during recent years towards mechanization and high-tonnage production methods has greatly increased ventilation requirements. The now of air must quickly dilute and carry away diesel exhaust fumes, dust created by mining operations, and the fumes of the explosives used in blasting. Mechanical ventilation is required to obtain the necessary volume and control, as natural ventilation pressures alone are, for the most part, inadequate and unreliable. In the event of a mine fire or other needs, close control of ventilation is essential.There are two unique heating systems presently in operation at Inco: Creighton Natural Heat Exchanger and Stobie Ice Stopes."

Jan 1, 1991

By O. Garg

This paper summarizes the computer applications in open-pit mine planning at the Iron Ore Company of Canada (IOC). A brief history of the use of computers at IOC is given, and a description of the existing facilities is outlined. The following systems are discussed: storage and retrieval of geological data; geotechnical data analysis; long-term grade and tonnage forecasting; ore grading; and open-pit mine design. Justification for using computers in open-pit mine planning is given, and possible future areas of application are considered.

Jan 1, 1979

"Projections of demand for Alberta coal indicate a quadrupling of current production rates to some 70 million tonnes/year by the end of the century. About half of this output-comprised of subbituminous coal-will be required within the province, primarily for generation of electric energy. The remainder-roughly 70 per cent high-volatile bituminous (hvb) steam coal and 30 per cent medium- or low-volatile bituminous (mvb/lvb) metallurgical coal-will be exported, principally to Pacific Rim and Western European countries. Direct employment in mining and coal processing is projected to increase from the present ca. 3000 to at least 12,000 persons.This paper presents separate forecasts for subbituminous, hvb and mvb/lvb coal production in the period 1982-2000; notes a number of possible developments that could substantially modify these forecasts; and briefly discusses attendant infrastructure requirements. Attention is drawn to potential shortages of qualified manpower and to threatening inadequacies of transportation facilities.IntroductionDespite the dislocations triggered by the 1973 'oil crisis', energy budgets of Western industrial countries are mostly still in the very early stages of the anticipated transition to greater reliance on coal. Shift s to coal are still more often only talked about than being implemented; and the public policies which are essential for timely development of facilities for producing, transporting and using coal are in many instances not yet even broadly formulated, let alone enunciated.In these circumstances, long-range projections of coal demand and supply-even if restricted to internal requirements- are subject to greater uncertainties than usually afflict such forecasts.On the demand side of the equation, these uncertainties arise ultimately from linkages between a need for coal and the availability and pricing of OPEC oil. The current surplus of oil on world markets, which has recently forced substantial reductions of posted prices, is undoubtedly a transient phenomenon that is unlikely to have any long-term impact."

Jan 1, 1982

By V. Fiedler, H. Lachmund, R. Bruckhaus

"After producing some 50 million tonnes of crude steel the two BOF vessels at Dillinger Hüitte steel plant had to be replaced in 2000/01 due to large deformations. The new vessel design was optimised after a number of theoretical evaluations.Refractory investigations were carried out as well as temperature measurements of the shell to provide a basis for selecting a suitable steel grade. This was found in a DH-GTS development - P420M HT - with high strength at elevated temperatures and excellent weldability and made it also possible to build the vessel without any cooling system.After putting the first vessel into operation the metallurgical results showed no remarkable improvement compared to the old vessel, and were therefore not satisfying. With the help of cold model investigations the arrangement of the tuyeres was modified to improve the flow conditions and the interactions between oxygen jet and the heterogeneous plume of the bottom stirring gas. Further optimisations were obtained by a variation of lance tips and a newly developed lime addition model."

Jan 1, 2004

By John C. Loretto

"The paper identifies two of the main problems encountered in recent hydrometallurgical plants for the recovery of gold and silver: firstly, the plant recovery is lower than anticipated from the testwork; secondly, the metallurgical accounting figures cannot be reconciled.The principal reasons for the plant recovery being lower than the testwork are discussed, together with solutions that can minimize these problems both during the design stage and during the plant operation after the problems have manifest themselves.The reasons for the difficulties in metallurgical accounting are analyzed by reviewing the various components of the plant figures. Recommended solutions are given for minimizing this problem and the realities of obtaining accurate figures are discussed.IntroductionThe start-up over the last few years of new hydrometallurgical plants for the recovery of gold and silver has brought to the surface again a number of problems. Most of the problems have existed for some time and they manifest themselves mainly in two ways. Firstly, the plant results do not agree with the metallurgical testwork figures; secondly, the metallurgical accounting figures do not balance.Metallurgical TestworkThe plant results not agreeing with testwork figures are mainly due to:a) testwork samples not representative of the eventual plant feed;b) misinterpretation or misunderstanding of testwork ;c) plant losses;d) plant design not allowing testwork results to be achieved;e) operating deficiencies."

Jan 1, 1982