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By D. M. Richards

"IntroductionThe Highland Valley Copper partnership was formed in July 1986 as a logical result of a mine with a large ore reserve but a small mill, and a mine with a large, modern mill but dwindling ore reserves. The original partnership of Cominco and Rio Algom was expanded in January 1988 to include Highmont Mining Company. During 1988/89 the Highmont mill was moved 7.5 km to adjoin the Lornex mill, becoming the Highland mill in the process, with a nominal capacity of 130 000 tonnes per day.The mine is located near the town of Logan Lake, 220 km northeast of Vancouver, British Columbia and 55 km southwest of Kamloops. The map in Figure 1 shows the general area. Kamloops is a major service centre and is served by two railways, two major roads and a regional airport. The mine site is situated between 1200 m and 1600 m above sea level on the Thompson Plateau. Principle activities in the area, in addition to mining, are cattle ranching and forestry. Ore reserves at the beginning of 1996 totaled 533 million tonnes at a grade of 0.42% copper and 0.008% molybdenum. Ore is mined from two pits — Valley, 3 km northwest of the mill; and Lornex, 1 km southwest of the mill. With 78% of the reserves, the Valley pit is the focus of activity.In order for Highland Valley Copper to remain competitive with a very low grade ore reserve, it has been necessary throughout the mine’s life for new technologies to be embraced as they become available. These have included such diverse technologies as in-pit crushing and conveying, large mechanical drive trucks, computerized truck dispatch and oneman survey instruments. During the next few years, it is planned to introduce two further technologies that are relatively new to both the world at large and the mining industry in particular. These are namely Global Positioning Systems (GPS) and Geographical Information Systems (GIS), both of which are expected to have a major impact on the way mining is carried out in the years to come."

Jan 1, 1997

By w. w. Milde

"Since its startup in 1975, the Rabbit Lake mill has been modified (0 process both increased tonnage and higher grade ore. Ore initially came from the Rabbit Lake pit . In 1985, a major mill expansion was commissioned to allow treatment of B-zone pit ore, which is mineralogically and metallurgically different fromRabbit Lake pit ore.Mill modifications, and the changing ore characteristics and processing targets which made them necessary, are described. Mill LocationThe mill complex, shown in Figure I, comprised of milling facilities, acid plant, power generation , warehouse and administration offices, is located approximately 1.5 Ian south of the Rabbit Lake pit, and about 8 Ian southwest of the B-zone open pit mine.Original Milling CircuitOre feed to the mill commenced June 10, 1975. The mill was designed to process 1500 tonnes per day , 483 000 tonnes per year with an average grade of O.44OJo Ups and an annual production of 2000 tonnes UPs' Run-of-mine ore was dumped directly onto a 60 em square opening grizzly. Oversize was broken with an Ingersoll-Rand hydrauli c rock breaker. Minus 60 cm ore was fed to a 6 m diameter by 1.8 m long Hardinge semi-autogenous (SAG) grate discharge mill. Mill discharge was screened over a Tyler double-deck vibrating screen, with screen oversize returned to the SAG mill feed chute via conveyor belt. Screen undersize (minus 2.4 mm) was pumped to 51 cm diameter Krebs cyclones in closed circuit with the SAG mill. Cyclone overflow (about 50% minus 74 micron) was thickened to 55% solids in a 30 m diameter neutral thickener .Thickened pulp was stored in two mechanically-agitated wood stave tanks (5.5 m diameter by 6 m high), to which sulphuric acid was added to obtain a pH range of 1.5 to 2.0. The fmalleaching was carried out in five more identical tanks. Sulphuric acid and sodium chlorate were used to maintain a pH of 1.5 and a terminal emf of -450 to -500 mV. Steam sparge was utilized to obtain a temperature of 45°C."

Jan 1, 1989

"Syncrude Canada Ltd. operates one of the largest surface mines in the world. The mining operation has two distinct phases: (1) the removal of the overburden, utilizing trucks and shovels; and (2) the mining of oilsand with drag lines and bucketwheels. Both phases combined move approximately 330 000 BCM per day.In support of current production demands and to provide a contingent oi/sand source, Syncrude has developed an Auxiliary Production System (APS) supported by the truck and shovel operation. This system utilizes oilsand sources within the existing mine area on an as-needed basis.The recent increased capabilities of the processing plant to handle a larger volume of oilsand has increased the reliance of the APS system. To facilitate the increased capacity, an auxiliary mine was developed external to the Base Mine operation with a production capacity of4.7 MBCM of oilsand per year.Development of the Northwest Auxiliary Pit began in January 1990, with the first cubic metre of oilsand taken to the plant in June, 1990. The Auxiliary Pit, as designed, has a total ore reserve of 68 MBCM of oi/sand."

Jan 1, 1993

Infrared spectroscopic data collected using HyloggerTM technology is being used to assess the mineral composition of Archean iron ore bedrock and Cenozoic detrital units in Western Australia’s Pilbara region. Analysis of infrared spectra enables quantification of: (1) composite iron mineralogy, (2) composite clay mineralogy, (3) hydrous silicates and (4) carbonate mineral abundances. Stratigraphic and rock mass unit logging of core has identified several detrital and bedrock units recognisable across the Pilbara. However, due to alteration related to mineralisation, weathering and later stage precipitate overprinting, it can often be difficult to assess the detrital-bedrock boundary and the occurrences of specific geotechnical units in the detritals and bedrock, particularly when using non-core drilling techniques and traditional geochemical assays. Infrared spectroscopic data collected concurrently on core from several sites has shown distinct correlation against existing unit subdivisions and associated geochemical parameters. Where infrared spectroscopic data have also been collected on rock chips recovered from reverse circulation infill drilling, these correlations allow robust geological and geotechnical models to be developed based on the typical mineralogical-geochemical signatures. The geotechnical sub-units identified in core can be readily distinguished using the various iron and clay minerals captured by the HyloggerTM technology as opposed to total iron, potassium, and alumina captured by geochemical assays. Further, some of the minerals targeted by infrared spectroscopic analysis (eg gibbsite, white mica, vitreous goethite) and their ubiquitous presence as the products of weathering, assist in recognition of various ancient weathering surfaces and help to define the origin of the material, whether bedrock or detrital. Overall, HyLogging of core and chips allows important mineralogy focussed data to be captured at minimal additional financial outlay. Correlations against geochemical unit identifiers are robust both within deposits and between deposits. Significant improvements in the confidence of geological and geotechnical models are attained.

Jan 1, 2015

By J. C. Kurnia

Presence of fine dust in air causes serious health hazard for mine operators resulting in such serious problems as coal workers? pneumoconiosis and silicosis. Major sources of dust appear of course along the mining face where the minerals are extracted. Proper control and management are required to ensure safe working environment in the mine. Presented here is the use of a computational fluid dynamic (CFD) approach to investigate the flow and dust behaviour in mining tunnels. The objective of this study is to propose and examine various strategies to mitigate dust dispersion from the mining face and reduce dust concentration to a safe level for the operator. In a companion study, the authors investigated various methods for mitigating dust dispersion from the mining face to ensure safe dust concentration levels in the mine tunnel. Among the examined methods, implementation of brattice to direct the flow from the main airway to the mining face is the most effective method to disperse dust particles away from the mining face. The installation of brattice, however, will limit the movement of mine operators and vehicles in the tunnel. Hence, application of a hybrid brattice which is a combination of a physical brattice along with suitable directed and located air curtains is proposed and examined. Based on the CFD simulation results, over a range of parameters of interest, it was found that the physical brattice blocks the ventilation air and directs it to the mine face while an air curtain located along the brattice outlet offers flexibility in keeping the dust away from the operator allowing more freedom for the operator and the equipment. Results of the modelling over a range of parameters of interest are presented and discussed with the goal of managing dust concentrations within safe limits for the operator.

Aug 1, 2013

By D. R. E. Whitmore, J. M. Harrison

There are five logical stages in the search for orebodies in virgin territory, namely: (1) reconnaissance inventory of geology, and related investigations; (2) development of broad concepts as a basis for selecting regions of potential mineral deposits; (3) assessment of criteria leading to specific localities within these regions; (4) geo-physical and geochemical studies that will delineate small anomalous areas; and (5) stripping, drilling or other means of locating ore. In addition, the development of new means of extracting mineral resources and the finding of new uses play a vital role in our mineral industry. The continued growth of this industry will be largely governed by our ability to develop or to adapt new concepts and techniques, and to produce a greater number of scientists and engineers. It should always be remembered that more than one-third of Canada's exports are dependent upon our ability to find, develop and economic-ally exploit new orebodies.

Jan 1, 1967

By L. M. Dwarkin

Introduction Avital factor in the success of any coal mining operation is the method of roof support employed. A coal seam in? place has been described as the filling in a geological sandwich and the process of mining as the art of snatching the filling from the midst of the sandwich. The difficulty of this task can be appreciated -in the realization of the tremendous weight bearing on a coal seam due to overlying strata; a weight that can exert pressures of several thousand pounds per square inch. Over the years that mining has been carried on, methods have been evolved by arduous trial and error, making possible the successful extraction of billions of tons of coal. However, these time-proven methods are not enough. The constant demand for faster and cheaper production, the necessity of mining under increasingly difficult conditions, and the requirement for higher standards of safety, call for ever better and more efficient roof support. A recent and very promising development in answer to this need is that of Roof Bolting. Roof Support in General Before proceeding to the subject proper, a brief discussion of the older roof support methods is of value in illuminating the difficulties involved and the problems to be solved.

Jan 1, 1951

By K. H. Concannon, K. I. Hindle

"The use of simulation modeling in the primary metals industry (including mining, smelting, and metals processing) is expanding as significant cost-benefits can be realized by companies employing capital intensive processes. The economic scale and complexity of operations found in this industry is well-suited to applications using this ""what-if' computer modeling technique, ranging from proof-of-concept projects to testing facility design or configuration, and determining resource requirements. More recently this technique is being used to support on-going planning and scheduling for operations using the simulation as the engine to derive the best schedule. With increased computer processing capability, deterministic models are now being developed to capture the workings of a production system or conversion process, allowing real-time monitoring and scheduling of these operations. This paper presents a sample of some recent discrete-event simulation modeling applications that demonstrate the capability and benefits of this technique in the primary metals industry. These include the use of simulation to support the long-range planning of underground mining operations; the modeling of a metals supply chain network that employs a multi-modal distribution system; the scheduling of a metals coil finishing process using a deterministic simulation model; and a more detailed description of the use of simulation to model furnace and converter aisle activities within a smelter operation in Northern Canada."

Jan 1, 2007

By J. Pontt

Gearless mill drives (GMD) offer high performance for torque and speed control for grinding mills and have been applied successfully in modern concentrators for wet grinding with mill diameters from 34 to 40-feet. It is considered a mature technology. However, recently, some large GMD?s have presented unexpected failures in stator and rotor subsystems. The phenomena involved in such failures has shown a complex nature and surprised users and manufacturers. The manifestation of such failures has been observed as mechanical damages to certain components of ring motors. This paper presents a discussion on the electromagnetic forces that can generate stresses in the electrical ring motor that can produce failures and outages. Guidelines for further research and contributions to improved reliability of GMD?s are proposed.

Jan 1, 2012

By L Gill

The four basic types of electric motors -squirrel-cage, wound rotor, synchronous and D.C. -are de-scribed, with particular reference to speed-torque characteristics. The three classifications of squirrel-cage motors, C.E.M.A. B, C and D, are compared, and methods of selection for specific drives are outlined. Wound rotor and synchronous motors are covered from the viewpoint of construction details, methods of operation and control required. The application of these motors to crushers, conveyors and ball mills is described and reasons for their selection are given. The application of D.C. motors to haulage equipment and mine hoist drives is included, and the basic principles of a variable voltage drive are illustrated. Efforts have been made through-out to provide specific examples of motor selection, with particular reference to the mining industry. THIS paper will attempt to answer the question -"which motor should be used for a specific drive?" Although it is impossible to cover the complete subject of electric motor application here, we hope to give some idea of the types of motors available and why certain types are used on specific applications.

Jan 1, 1963

By A. P. Yovanovic, P. Bonadia, M. N. Moraes, C. F. Matos

"The magnesite flotation operation of Magnesita Refractories, in Brumado – Brazil, has four parallel ball mills working in closed circuit with hydrocyclones to grind the ore for the reverse flotation of silicates in mechanical cells. The modification proposed here opens the circuit for three of the ball mills so that their products are collected together to feed a high frequency screen. The oversize of the screen feeds the fourth ball mill in closed circuit for secondary comminution. The product reports to dewatering and flotation. The undersize undergoes desliming and subsequent flotation operation. According to pilot tests performed, the modification on the magnesite flotation operation will promote a 20% increase in the productivity, 8.5% increase in mass recovery and a 26% reduction in water consumption. The gains are due to the fact that the silicates in the feed are concentrated in the smaller particles (<100µm) with over grinding in the existing closed comminution circuit, making it impossible to take advantage of this natural selectivity. The combination of open circuit, more selective milling, and the high frequency screen, ensures high efficiency particle size classification. This renders the process more effective, both to the screen undersize with its high contents of silicates and fines, and to the screen oversize, which is almost without fines and has a higher magnesite grade. This situation allows for the setting of specific parameters for the flotation of both the primary milling undersize and the secondary milling product.INTRODUCTIONMagnesita Refractories, with its operations site in Brumado, is the largest producer of high purity dead burned magnesia (DBM) in Latin America. The magnesite ore is extracted from an open pit mine, named Pomba, after which it is crushed and handpicked. Due to the presence of disseminated silicate the ore has to be ground and concentrated by means of reverse flotation, before feeding the high temperature kilns for sintering and conversion to DBM.The magnesite flotation unit has an impact crusher to reduce the size of the feeding ore, which is transported to the mills by conveyor belts. The milling operation is composed of four ball mills in closed circuit with hydrocyclones. The closed circuit generates a high circulating load with excess fines, which is detrimental to the selectivity of the desliming and flotation operations, reducing both mass andmetallurgical recovery.In the current scenario, the capacity of the flotation plant is insufficient to meet the demand of the DBM kilns, forcing the operation to work with high purity ores in order to attain the highest possible mass recovery in the concentration process. This is not an ideal situation as it requires the mining site to work with higher stripping ratios.The objective of this work was to improve the magnesite flotation unity to increase its productivity. After a detailed analysis, the milling was identified as the limiting process, which made the authors to focus on this operation."

Jan 1, 2016

By E. Swartzman

"DURING 1951, experimental cleaning studies on both fines and larger sizes of certain Canadian coals were conducted on a relatively large scale in two pilot plants in the United States, large enough to be considered as small commercial units, and in one commercial plant in Canada.One of the pilot plants was a wet washer of a type which apparently has never been .used in Canada, nor has any Canadian coal been tested in it before. In the other pilot plant and in the commercial plant, dry cleaning equipment was used. The commercial plant is the first of its kind to be employed in Canada, and this type is used only to a limited extent in the United States.Fine-Coal Cleaning ExperimentsTest PlantsHydrotator and Hydrotator-Classifier combination pilot-plant with a capacity of about twenty tons per hour. This is a classifier type washer adapted for cleaning fine coal as well as certain intermediate sizes. The Hydrotator deals with that portion of a coal retained on approximately a 24-mesh Tyler sieve, whereas the Hydrotator-Classifier deals with the minus 24-mesh fines."

Jan 1, 1952

By L. W. Krahenbil

The programmable Logic Controller (PLC), at its present stage of evolution, is now considered as a mature control system. The PLC combines the solid-state reliability of hardwired logic and computer control systems with the simplicity of a relay ladder logic. Relay symbolic programming through a function-oriented keyboard provides a means which plant personnel can easily become accustomed to work with. In a large coal facility, it is shown that the control engineer can provide improved control flexibility with the advanced capabilities of the PLC.

Jan 1, 1979

By J B. Maughan

Gas and oil seeps have been known in Quebec for more than one hundred years. These occur in three main areas which contain sedimentary rocks with a total thickness estimated to vary from 6,000 to 20,000 feet. The strata in these areas are similar in many respects to those in producing areas of southwestern Ontario and the Appalachian basin, and the prospects for finding and developing commercial reserves of oil and gas in Quebec would therefore also appear to be favourable. Little of the exploratory drilling to date has been con-ducted in a systematic manner, and most of the drilling has utilized improper or inadequate equipment. Many wells have also failed to adequately test and fully evaluate the principal zones of interest. Relatively high drilling costs have hindered systematic exploration; however, with improved portable equipment, it is expected that future wells can be drilled with greater efficiency and at less cost. Most of the mineral rights in Quebec are held by the Provincial Government, and acreage can still be leased in large blocks on favourable terms.

Jan 1, 1964

By Ray Holmes

This paper describes one approach in our search for greater stope efficiency and lower costs. The uppers technique with wagon drills in cut-and-fill stopes was commenced, on an experimental basis, in our Sudbury mines in 1961. To date, the method has developed into an accept-ed production operation. This technique minimizes the intermittent aspects of the drilling, blasting, mucking and filling operations associated with other cut-and-fill methods. However, studies show that not all cut-and-fill stopes are suitable for uppers, the governing factors being ore width, dip of the orebody, and ground conditions where large areas of unsupported back remain stable for ex-tended periods of time until rockbolting can be accomplished. Introduction F ALCONBRIDGE Nickel Mines Limited operates seven mines within a radius of 30 miles of the city of Sudbury, Ontario. These mines extend in depth from 1,500 to 6,300 ft. The ore consists of brecciated, massive and disseminated sulphides, and the ore minerals consist primarily of pentlandite, pyrrhotite and chalcopyrite. Widths are generally irregular and vary up to 150 ft. The ore dips at between 35 and 90 degrees.

Jan 1, 1965

By S. Jain

Construction industry is considered as labour intensive, having shortage of skilled labour, unsafe with large number of industrial accidents. Construction industry requires high technology automation products (Robots) for improving productivity, safety, quality etc. Robots are developed by various countries in different areas like demolition, earthwork, bridge, tunnels, road work, underwater works, trenches and piping, maintenance etc. however they are still not used to their full potential by construction industry. Hence in this paper, the authors propose a ?model for adoption? of robots in construction industry. This model considers how a construction firm will adopt full scale robots like manually controlled machine, tele-controlled machines, computer controlled machines and cognitive robots and assimilate them through various stages.

Aug 1, 2013

By G. D. Markland

"The Moose Mountain mine is located in a belt of Precambrian volcanic rocks situated 20 miles north of Sudbury, Ontario. It was the first iron mining operation in the Archean iron-formations of the Canadian Shield.The ore is believed to have been formed in an environment of active volcanism, being part of a pyroclastic and volcanic series where only the iron-formation and chert qualify as chemical sediments. The volcanic environment, subsequent regional tectonics and metamorphism produced orebodies which differ from the main sedimentary iron ranges of the world in such features as continuity, grade, structure and metallurgical characteristics. The orebodies occur as relatively small lenses which have been complexly folded, faulted and intruded by acidic and basic dykesAlthough the basic mining and beneficiation methods are simple, detailed geological control in exploration, planning and operation has been necessary to apply detailed selective techniques to the large-scale open-pit methods necessary in profitable iron mining.The milling and pelletizing processes are sensitive to minor variations in ore grade, grain size, fabric and mineralogy. Although detailed correlations of geological information and mill performance are still not entirely satisfactory, general working relationships have been determined with simple testing procedures. These are of in-creasing use in forecasting production and in ore-blending processes.The application of geology to mining and milling operations at Moose Mountain represents a departure from general practice in iron ore operations."

Jan 1, 1966

By Hao Zhang

Site inspection is an important component of safety management system. In current practices, the inspectors evaluate the safety condition on a construction site with the assistance of a standardised checklist. However, the checklist emphasizes on evaluating the implementation of safety management system, but provides limited task-specific check items for assessing whether the individual construction tasks are conducted under safe condition and in a safe manner. To address this issue, the research presented in this paper aims to provide safety practitioners with comprehensive and taskspecific safety information to promote effective risk identification and facilitate strategic risk control during site inspection. Specifically, this research first builds a project-specific safety information database, which stores potential risks and control measures for each construction task. The research team then develops a mobile decision support tool to retrieve information from the database and support safer decision-making on site. The tool supports users in two ways: one is to provide daily risk checklists and risk control strategies to guide step-by-step inspection alongside the project schedule; the other is to let users input any safety-related keywords during the safety inspection process and the tool returns relevant safety information by applying text mining algorithms. It is ongoing research. This paper presents an overall research framework and discusses the progress in developing safety database and data retrieval concepts. The outcome of the project will help enhance safety management practices and reduce possible risky working conditions on a construction site.

Aug 1, 2013

By Paul Hammond

Abstract The Allard Lake ilmenite deposits, which are currently being developed on a large scale, occur as a series of dykes or lenticular, flat-lying bodies within the northeastern part of a large, oval shaped anorthosire mass of Precarnbrian age which lies with its long axis paralleling the gulf of St. Lawrence. The Lac Tio deposit, discovered by Kennco Explorations, Limited, in 1946, is the largest body of titanium ore of its type now known in the world. It contains upwards of 112,000,000 short tons of ilmenite ore averaging 32 per cent TiO2 and 36 per cent Fe. The ore is an aggregate of ilmenite with oriented microscopic blades of hematite. The deposits appear to be high temperature, late magmatic injections containing only a small amount of volatiles, and bear a genetic relationship to the anorthosite rocks in which they occur. * * * Introduction Recent developments on the ilmenite deposits in the Allard Lake district of Quebec indicate the probability of a major industry, and one which may make Canada the world&apos;s greatest producer of titanium pigments and, ultimately, of titanium metal. The presence of ilmenite in this district was first reported by the Quebec Department of Mines following a reconnaissance shore-line geological survey in the year 1941. The ensuing report by Retty describes the occurrence of a number of small ilmenite lenses about the shore of Allard lake and&apos; along two smaller lakes in the vicinity. These showings were later staked by Toronto and Montreal interests who carried out a certain amount of development work, and were described in more detail by Longley for the Quebec Department of Mines. The claim groups were later optioned by Kennco Explorations, Limited, Canadian subsidiary of Kennecott Copper. None of the deposits in themselves constituted a sufficiently large body of ore to warrant the major construction expenditures necessary for their exploitation on a profitable basis. The surrounding anorthosite areas, however, were considered favourable for the possible occurrence of other ilmenite deposits

Jan 1, 1949

By D. W. R. George, J. L. Stewart

Developments in the last decade, which have contributed to increased productivity and decreased coke rates in the iron blast furnace, are reviewed. Future progress in blast-furnace practice is also considered.

Jan 1, 1966