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By S. Wood

"Plastic Filled Valley (PFV) wire rope represents a significant development over the design of conventional wire rope. A sealing thermoplastic is impregnated under controlled conditions of temperature and pressure into a conventional lubricated wire rope to produce a lattice of plastic which surrounds and separates the strands from each other and from the core. Metal-to-metal contact is thereby alleviated and the lubricant is sealed in. The wear resistance, rope breaking load, fatigue resistance and crushing resistance are all increased. The result is a rope which offers exceptional service life.Laboratory tests carried out in Canada and at the University of Stuttgart, in West Germany, confirm the increase in fatigue life. The field trials conducted so far have indicated that the results obtained in the laboratory can be duplicated in the field.IntroductionIn times of double -digit inflation, the consideration given to operating costs throughout industry commands considerable attention. The same can be said of the mining industry. A set of large-diameter wire ropes used on the huge draglines in strip mining can cost in excess of $100,000. Because a machine may use three sets of rope s each year, it is clear that the costs of wire rope can contribute a considerable percentage to any operating budget. As wire rope is a product which is used extensively throughout the mining industry, it would appear timely to turn our attention to any ""Method of Extending Wire Rope Service Life"" in order that wire rope life can be optimized and wire rope costs can be minimized."

Jan 1, 1982

By K. K. Feng

"Spontaneous combustion has always been a problem in coal mines and is identified mainly with the mining of low-rank coals. The liability of coals to spontaneous heating is only one of the factors in determining whether spontaneous combustion will occur. However, knowledge of the relative oxidizability of the coal is a useful factor to take into consideration when selecting new coal seams and mining methods for future mine development.Four methods (static isothermal, ignitability, adiabatic and dynamic) have been used to compare the relative liability of Canadian coal to spontaneous combustion and to investigate the mechanism of spontaneous combustion of these coals. Among these f our methods, the static isothermal method is considered to be the best indicator of the susceptibility of various coals to spontaneous combustion. Western mountain coal adsorbs more oxygen and has a higher tendency to undergo spontaneous combustion than the Harbour seam coal of Nova Scotia. It has also been observed that a higher methane content in coal will indicate a lower liability to spontaneous heating."

Jan 1, 1985

By Y. Wong

The quality and quantity of secondary deposits, which include tailings streams and tailings dams, are increasing around the globe. The tailings are already mined, available and liberated to such an extent that the recovery of a valuable product is highly economical in terms of CAPEX & OPEX. The most widely used process for the recovery of these valuable ultra-fine haematite iron particles is the Wet High Intensity Magnetic Separation technique, originally developed by Dr. Jones over 55 years ago. Many of the original machines are still working today. The aim of this paper is to demonstrate the capabilities in terms of grade and yield of using sophisticated magnetic separation modules. All results and figures are obtained from test works, design- and engineering works. Two types of tailings have been identified for processing. Firstly, tailings that have already been deposited in a Tailings Storage Facility, and secondly, live tailings streams from an existing wet iron ore beneficiation plant. In both cases, the technical and practical results are shown along with relevant flow sheets and plant layouts. Finally, this paper highlights the total predicted power- and water consumptions, capital requirements and projected operating expenses. The results show that the operating costs are significantly lower than the mining and processing operations which are required for an equivalent amount of iron ore. The recovery % of iron depends on various factors but is within the 30–50% range, at an equivalent grade to the mainstream product. Another significant benefit is that the magnetic separation process is water positive, meaning that water is released rather than added in the process. The processing of secondary deposits will therefore result in an overall reduction in operating costs, an increase in product yield from a plant, extend the mine life and offer environmental benefits by reducing the tailings footprint and water usage.

Jan 1, 2016

By Denis Landry

"RÉSUMÉAu cours de dix dernières années, la compagnie Maghemite a développé, expérimenté et breveté un nouveau precédé de concentration du minerai de fer à partir de la récupération d'hématite présente au bassin de sédimentation de la Compagnie Minière Québec Cartier.A partir de cette nouvelle technologie de concentration par induction, la compagnie Maghemite produit une poudre d'hématite qui est mélangée avec du strontium carbonate à un ratio de l à 6 en poids. Le mélange homogène est achemine sur un disque d'agglomération, et ensuite incorpore dans la fournaise de la Compagnie Minière Québec Cartier. Le temps de cuisson et la température (l200°C) correspondent exactement aux critères nécessaires pour la fabrication d'aimants de céramique, Grade 5, à partir de la poudre de ferrite.IntroductionMeghemite a débuté sa production de poudre de ferrite au printemps 1986et prévoit une production de 20 000 tonnes par année dans cette nouvelle usine. A très court terrne, une usine sera construite pour la production de cinq à dix millions de Iivres d'aimants permanents par annee et à long terme qu'une usine de fabrication par robotique de moteurs à aimants permanents, utilises dans I'industrie automobile. La poudre de ferrite à base de strontium est une compose ferro-magnétique forme d'une molécule d'oxide de strontium et de six molécules d'hernatite. Ce compose d'hexa fluorite de strontium a une force tres puissante et fournit la source d'énergie magnétique la moins dispendieuse comparée aux autres aimants permanents. L'utilisation des aimants de céramique formes d'hexa fluorite de strontium a connu un croissance phenornenale depuis 1970 pour atteindre un marché de 500 millions de livres par année en 1985.II n'y a aucune autre usine de production commerciale de poudre de ferrite à base de strontium au Canada. Le facteur determinant qui a favorise l'etabilissement a Port Cartier est base sur la réduction de 30% du cout des aimants de cerarnique provenant de notre poudre. Notre debouche majeur se situe aux États-Unis et vise la production des aimants de cerarnique pour les moteurs utilises dans les automobiles, les ordinateurs et les appareils ménagers, L'objectif de cette compagnie est de réduire le prix futur des aimants de cerarnique à environ 30% du prix actuel.L'usine commerciale de production de poudre de ferrite est maintenant opérationnelle. Le financement et la construction de cette usine sont Ie résultat de l'opération d'une usine pilote sur une période de 5 ans afin de récupérer l'hematite d'un haut niveau de pureté provenant de résidus de I'usine de bouletage de la Compagnie Minière Québec Cartier (CMQC) à Port Cartier. La fournaise de CMQC est utilisee pour chauffer les boulettes cornposees d'un mélange de carbonate de strontium et d'hematite d'un haut niveau de pureté en étalant environ 5 tonnes à l'heure de ces boulettes au-dessus du tablier de boulettes de fer dans une des fournaises fonctionnant à environ 450 tonnes à l'heure."

Jan 1, 1987

By V. C. Wittchen, T. R. Yu, J. E. Croxall

"The consolidated rockfill at Kidd Creek Mines is a weakly cemented, minus 15 cm aggregate which posed problems for conventional drill/blast drifting methods. Consequently, lateral access to mineable ore adjacent to backfilled areas was gained by drifting around the fill in shattered rock.In mid-1987, Kidd Creek Mines began to investigate means of mechanically excavating drifts in backfill . The results of this investigation led to a trial program using a Dosco MK-2A Roadheader to excavate the required drifts in backfill.The roadheader was tested at Kidd Creek Mines from July to November 1988, in 28-735 X /C to be used as the top access for drilling and blasting 32-74/ ST. During this period, the roadheader excavated 54 m of a 4.3 m by 3. 7 m arched drift in backfill. Cutting rates over the period averaged 0.8 m/cutting hour as projected with a daily high of 2.0 m/cutting hour.Wood-lagged 2-piece steel arches on 1.2 m centres were chosen as ground support for the trial. Shotcrete will be tested in a roadheader drive for its potential to improve productivity by replacing the steel arches.The trial program included evaluations of point-attack picks, two sizes of cutter motor, 20 MPa (3000 psi) water-assisted cutting, cuttings-removal systems, and environmental control devices."

Jan 1, 1990

By V. G. Minenko, A. L. Samusev

For efficient leaching of gold from sulfide ores and the oxidation of sulfides into sulfates, it is necessary to introduce a substantial amount of oxidant - atomic oxygen, hydrogen peroxide, ozone, potassium or sodium hypochlorite. In this paper, hypochlorite electrochemical treatment is proposed as an effective method of intensification of refractory ore leaching. The objective of the study is to increase the gold recovery from refractory ores with the application of chlorinated solutions that are modified by chemical or electrochemical treatment. The advantages of the use of the modified chlorinated solutions instead of cyanide for gold-sulfide leaching are considered to be the following: a high concentration of the oxidizing agent (hypochlorite ions) in solution helps to achieve a high speed of gold dissolution in the form of chloride complexes; the possibility to produce hydrochloric acid solutions that may be used for the recovering gold by electrolysis; the possibility of the processing of carbonaceous, arsenic-bearing and others kinds of refractory gold ores. The mechanism of the interaction of the modified chlorine solutions with gold-bearing sulfides (pyrite and arsenopyrite) was investigated. The efficiency of the application of chemical and electrochemical leaching method was proved. The main factor that limits the rate of gold dissolution is a high concentration of sulfate ions (SO4 2-) formed in the solution by the oxidation of sulfide minerals. The optimal parameters of chemical and electrochemical leaching method and effective ways to remove sulfate ions were determined. The method helps to increase the level of the gold recovery up to 87% from refractory ores. The intensification of leaching by chemical and electrochemical treatment opens up opportunities for the creation of modern efficient and environmentally-friendly technologies that may be applied for gold extraction from refractory gold ores.

Jan 1, 2016

By Bertrand Wolfman, William E. Stanley

"This paper reviews the traditional mine accounting systems, including ""custodial accounting"" and unit costing, and then suggests that the use of flexible budgets represents a more suitable method of reporting costs in order to assist the mine manager in improving productivity. Examples of various applications are given to show that the result is a clear reporting structure.Custodial Accounting is Emphasized in Traditional SystemsTraditional mine accounting has been mainly concerned with the accuracy of financial reporting to ""head office"" for the use of the directors and the company's bankers and shareholders. This is often called custodial accounting and it represented the main purpose of accounting when first developed in Europe hundreds of years ago. This important development permitted the establishment of enterprises which were separated from their owners because they could rely on accurate financial reports of management's stewardship.As custodial accounting is fairly broad and historical in nature, it is often not very useful to the mine manager for ongoing monitoring of performance of mining, milling, maintenance, and other support and staff groups. In spite of the considerable investment in accounting staff and computer support, many accounting systems have not been upgraded so that they accurately reflect workplace performance on a weekly or monthly basis.Budgets are Often FixedMany mines today also still emphasize fixed budgets. Thus, the mine plan which is set in the fall of one year is converted to a monthly tonnage and detailed dollar budget for periods of up to sixteen months in the future. The only certainty in this plan is that actual events will differ; timing, mix of mining methods and production volumes will differ on a monthly basis.Unfortunately, the fixed budget has no capability to reflect these operational changes. It is frozen for the full year. The result is that actual results will inevitably be compared to an outdated target."

Jan 1, 1982

By Francis Dakubo, Courtney Young, Avimanyu Das

"Hydrometallurgy of copper ores typically involve acid leaching followed by solvent extraction and electrowinning (SX/EW). EW is the final purification stage in which a voltage is applied across two electrodes causing the copper ions to reduce and deposit on the cathode. Applied voltages are near 2 volts with current densities around 300 amps/m2. In this study, research was undertaken to decrease the energy consumed in the EW process. To do this, various cell designs were constructed and tested in which a membrane was used to separate the cathode and anode compartments with concentrated solution from SX serving as catholyte and raffinate from SX serving as anolyte. Therefore, copper in the concentrated solution would be deposited on the cathode while ferrous in the raffinate would be oxidized to ferric at the anode. Because it is assumed that ferric acid leaching is used, resulting ferric would be recycled to the leaching process. A positive side effect of the envisioned process would be the elimination of oxygen evolution at the anode and thus the prevention of acid-misting. After a cell design was selected, it was used to test a number of variables: flowrate, concentration, temperature, ion-exchange membrane, and applied voltage. Following experiments in which variable ranges were determined, statistical modeling was conducted using STATEASE software. Optimal results indicate the voltage can be decreased to 1.5-1.7 volts with current densities of 300-400 amps/m2. Significant reduction in the energy consumption was accomplished by reducing the applied voltage. Furthermore, current efficiencies and copper production rates was increased by application of the membrane.INTRODUCTIONLeaching of copper ores is achieved using mostly sulfuric acid. The copper pregnant solution is contacted with an organic solvent or resin adsorbent which picks up copper ions as in Equation 1:"

Jan 1, 2016

By M. Maldonado, P. Olivares

"A submersible sensor for real-time gas holdup measurement in the collection zone of industrial flotation machines is introduced. The working principle is based on the generation and measurement of a pulp flow using a gas-exclusion cell immersed in the aerated slurry. The gas exclusion cell consists of a variable-area open vertical tube designed to be filled only with pulp by preventing gas bubbles entrance. The higher density of the fluid column within the cell generates a downward flow of pulp; the rate of this flow is proportional to the gas holdup outside the cell. The gas holdup measurement is achieved by tracking the velocity of the pulp flow leaving the gas-exclusion cell, using a magnetic flowmeter. Construction details of a prototype and its testing in two- and three-phases are discussed.INTRODUCTIONFlotation process optimization consists of finding and maintaining operating conditions that maximize flotation performance measured in terms of recovery and grade. The selective separation of mineral particles proceeds in two interactive zones where different and simultaneous phenomena take place: in the collection zone, the valuable particles are separated by collection on the surface of bubbles, while in the froth zone, the bubble-particle aggregates are gathered, drained to remove entrained particles, and taken into the concentrate stream. The cell overall performance, which can be determined from proper stream sampling, is a function of the recoveries in the individual zones. These zone recoveries cannot be independently measured nor calculated from operating variables. Progress in the assessment of these recoveries has been slow because on-line and reliable sensors to measure properties of the drastically different dispersions existing in both zones are not available.In the case of the collection zone, it has been demonstrated that the recovery of hydrophobic particles on the surface of bubbles, considered as a process with first-order kinetics, correlates with the bubble surface area flux (Finch et al., 2000; Hernandez, et al., 2003; Lopez-Saucedo et al., 2012). Bubble surface area flux (bubble area generated per unit time and cell cross-sectional area), is a variable affected by gas flow rate, bubble size distribution, and frother type and concentration. Gas holdup (volumetric fraction of gas dispersed in the slurry) is also affected by the same variables, and as such, carries information on the interacting variables that define the performance of the process. Therefore, a correlation between gas holdup and bubble surface area flux was expected and demonstrated (Finch et al, 2000), and since gas holdup is easier to measure as no bubble size is required, it has the potential to be the basis of a cell control and optimization strategy if a continuous sensor is available."

Jan 1, 2016

By D. F. Sangster, P. J. Hood, G. A. Gross

"Some results are presented of an integrated geological and geophysical study of Precambrian magnetite-quartz iron-formation in the Kapiko Iron Range north of Nakina, Ontario. Detailed geological and topographical mapping was carried out in conjunction with detailed geophysical investigations such as vertical magnetic field, vertical magnetic gradient, hammer seismic, horizontal-loop electromagnetic and magnetic susceptibility surveys. In addition, oriented drill cores were obtained for magnetic polarization studies.Vertical-force magnetic anomalies within individual rock units showed a strong positive correlation with topographic relief. Moreover, magnetic intensity was found not to be quantitatively proportional to the magnetite content in the rocks, due to the presence of high remanent magnetization of the magnetite. Also, the remanent polarization direction was sub parallel to the plunge of the fold structure and mineral lineation in associated rocks.Vertical magnetic gradient measurements were found to be more accurate in locating buried contacts between magnetite-quartz iron-formation and country rock than the vertical magnetic force data.An in-situ magnetic susceptibility meter was used to measure the magnetite content of iron-formation, and the measurements were subsequently compared with vertical-force magnetic results.The results of the EM survey were inconclusive; some magnetite-rich zones produced anomalies in the out-of-phase component. whereas others did not. The reasons for such inconsistencies are not yet apparent.Longitudinal seismic wave velocities measured parallel to the bedding in magnetite-quartz iron-formation ranged from 10,600 ft/sec. to 14,500 ft/sec. The seismic velocity appears to increase with an increase in deformation of the rocks."

Jan 1, 1966

By Noel Billette, Jean-Luc Chouinard

"An analysis of the number of industrial injuries shows that the mining sector is particularly affected, since mining is one of the most dangerous industrial activities in Canada. This has led to numerous inquiries, and supports the need for an in-depth study aiming at the identification of factors responsible for these accidents. One possible factor often pointed at is the small crews incentives and this paper presents a scientific approach applied to check a potential link between bonus and accidents at two mining companies located in northwestern Quebec.The data required to do so were the accidents, the salaries and the number of hours worked at each mining site by the hourly paid personnel for the period from June 1979 to January 1982. The analysis of the results derived from the initial information shows different behaviours of the frequency rate vs the bonus rate at these mines. The number of days lost per accident is independent of the bonus rate at both mine sites, as shown by Khisquare tests on contingency tables.IntroductionA wide variety of opinions has been pinpointed by a survey of the literature related to individual or small crew incentives and industrial accidents in sectors of activity where it applies. In addition, various formulae of mining contracts take place in the industry on one part, and statistics from this sector indicate a high accident frequency rate on the other part. These fact s have lead to this scientific investigation which does isolate the direct impact of the bonus on workers' accidents. This study was undertaken with the full support of the Quebec Metal Mining Association.The conclusions of this preliminary phase of the researchproject are presented for two mining complexes in northwestern Quebec. The procedure is somewhat similar to the approach of the Belmoral Commission, with the underlying assumption that bonus has a direct impact on accidents."

Jan 1, 1986

By Gaétan Bourdages

A clarification technology used by municipalities to produce high-quality drinking water, polish sewage treatment plant effluent and handle combined sewer overflows has recently found new applications in the mines and iron and steel industry. This patented process, known as ACTIFLO®, utilizes microsand in a ballasted flocculation process to enhance the settling characteristics of suspended solids, increasing the efficiency sufficiently to achieve a clarifier footprint that is smaller than the one of a conventional clarifier. ACTIFLO® rise rates vary from 40 to 170 m/h with a total system hydraulic retention time of about 10 minutes. The result is a clarification system so compact that a full-scale system can operate as a trailer-mounted unit for temporary applications or as a permanent installation in facilities with space limitations. This paper explains the process and presents case studies in which this innovative technology was used at mines and steelmaking facilities to meet compliance requirements.

Feb 1, 2008

By L. Nastac, Y. Xuan

"The metal-matrix-nano-composite (MMNCs) in this research work consists of an A356 alloy matrix reinforced with 1.0 wt. % SiC 50 nm diameter nanoparticles that can be dispersed within the molten alloy matrix via ultrasonic stirring technology (UST) and induction melting and stirring processing. The necessary ultrasonic parameters to achieve the essential cavitation for adequate degassing and refining of the A356 alloy as well as the optimum fluid flow characteristics for uniform dispersion of the nanoparticles into the A356 alloy matrix have been investigated in this study by using computational fluid dynamics (CFD) modeling with a magneto-hydro-dynamics (MHD) model and an UST cavitation model.The MHD model accounts for turbulent fluid flow, heat transfer and solidification, electromagnetic field as well as the complex interactions between the solidifying alloy and nanoparticles by using ANSYS Maxwell and ANSYS Fluent Dense Discrete Phase Model (DDPM) and a particle engulfment and pushing (PEP) model.INTRODUCTIONAluminum matrix nanocomposites can offer outstanding properties, including low density, high specific strength, high specific stiffness, excellent wear resistance and controllable expansion coefficient, which make them attractive for numerous applications in aerospace, automobile, and military industries field (Bozic, 2010, De Cicco, 2009, Elshalakany, 2014, Goh, 2006, Jia, 2013 and 2015, Liu, 2014, Reihani, 2006, and Su, 2010).As shown in literatures (Aki, 1999 and Mussert, 2002), it is highly advantageous to use nano-sized ceramic particles to produce metal matrix nano-composites (MMNCs) since similar ductility and higher strength with the metal matrix can be achieved. Currently, there are several fabrication methods of MMNCs, including mechanical alloying with high energy milling (Chen, 1997) , ball milling (Filho, 2003), nano-sintering (Groza, 1999), spray deposition, electrical plating, sol-gel synthesis, laser deposition, etc. The mixing of nano-sized ceramic particles is normally lengthy, expensive, and energy consuming.Ultrasonic Stirring Technology (UST) has been extensively used in purifying, degassing, and refinement of metallic melt (Jian, 2005, Khalifa, 2008, Eskin, 2002, Xu, 2004, and Meek, 2006) mainly because introducing the ultrasonic energy into a liquid will induce nonlinear effects such as cavitation and acoustic streaming. SiC nanoparticles are widely used as reinforcement particles due to their relatively good thermal and chemical stability. Ultrasonic vibration can improve the wettability between the reinforced nanoparticles and the metal matrix (Lan, 2004, Cao, 2008, and Yan, 2011), which will assist to distribute the nanoparticles more uniformly into the metal matrix. Ultrasonic cavitation in liquids causes high speed liquid jets of up to 1000 km/h. Such jets press liquid at high pressure between the particles and separate them from each other (Hielscher, 2005)."

Jan 1, 2016

By J. Bigu, M. G. Grenier, S. Hardcastle

"This study was undertaken in a belt conveyor drift of an underground hard rock mine. The conveyor transported ore or waste from a crushing operation located upwind from the drift sampling locations. A 250 m section of this drift was selected and several types of measurements were taken. Average respirable concentrations in the drift were 0.43 mg/m3 and 0.19 mg/m3 for total and silica dust, respectively. From the respirable dust concentration profile along the drift, it may be possible to estimate the contribution from extended sources such as dust produced by the belt and return idlers.The airborne dust in the drift had an average mass-median aerodynamic diameter of 4.2 micron. A continuous dust monitor showed that the crushing operation produced fairly high dust concentrations (sometimes greater than 4 mg/m3) over short periods of time.IntroductionAirborne dust in the respirable range is known to be the cause of various forms of lung ailments . In underground mines, respirable dust sources are created at many stages of production. All mining operators are responsible for de signing and establishing means of reducing airborne dust. In some cases, sources of dust are well defined and suppression methods are standard.In the case of interest here, the airborne dust cloud was formed from the contribution from many sources, which may be either discrete or extended. At the experimental site, the discrete or point sources were the crushing operation and the belt conveyor transfer point (tail pulley). These sources may be controlled by proper dust capture and scrubbing systems as well as dilution ventilation. Examples of extended dust sources in the area include dust produced by the re-entrainment of settled particles along the drift. Ventilation air movement and vehicular traffic both contribute to this phenomenon. Dust produced by the conveyor is another example of an extended dust source. Caked deposits on the return strand and idlers as well as the transportation of dry material on the belt, can be major contributors. Proper wetting of roadways and muck as well as proper belt cleaning techniques can help reduce these emissions. The cleaning apparatus, used on the belt where these experiments were conducted, is shown in Figure I. These and other belt cleaning techniques are described in more detail elsewhere."

Jan 1, 1987

By D. G. Champion

"A comparison of diesel engine power ratings with in-service capability, and the selection of unit size and total number of units are discussed in the paper. Engine specific fuel consumption and its evaluation in relation to manufacturers' tolerances and equipment load factors is reviewed along with the suitable plant layout. The potential for heat recovery is discussed in connection with simple and operable recovery systems f or exhaust and cooling circuits. Maintenance standards as related to improved reliability and reduced fuel and operating costs are also outlined. IntroductionDiesel generators are used in Canadian mining operations to provide electrical power for "" base- load"" requirements in some instances and for ""stand-by"" or ""emergency"" power in almost every producing mine in the country . There are over 300 mines in Canada of which only a handful have to generate their own electricity. Only one or two mine s enjoy access to a hydroelectric site. Consequently, the diesel engine is the principal prime mover because of its high efficiency relative to other prime movers in the size range in question.The author has been associated with several “base-load” plants in addition to participation in numerous projects requiring emergency diesel generators. Records indicate that engine performance in term s of reliability and efficiency lags behind other industries where the diesel engine is used more extensively, such as the shipping industry which is able to make a more prudent selection of original equipment and enjoy easy access to highly skilled operating and maintenance personnel. It is hoped that the contents of this paper will be of value to Canadian operators of diesel generators, in the generation of prime power or applications for back-up power."

Jan 1, 1986

By D. W. Euler, B. J. Clauzier

"Implementation of an effective energy management system will reduce energy costs without impacting negatively on production.The energy management system must be designed to complement the operation and be integrated with the organization. It must be reliable and easy to use but most important, it must have an accurate and timely feedback reporting system to allow the operation to take appropriate action.Falconbridge Limited was one of the first three companies to be awarded the energy monitoring demonstration program in May 1987. The program is sponsored jointly by the Ontario Ministry of Energy and Ontario Hydro.This paper describes the approach taken by Falconbridge Limited to implement the Onaping Area Energy Management System.IntroductionThe objective of the project was to implement an effective energy management system, capable of reducing energy costs without impacting negatively on production.Energy management systems must be designed to complement the operation and to be integrated with the organization. The system must be reliable and easy to use, but most importantly, it must have an accurate and timely feedback reporting system to allow the operation to take appropriate action."

Jan 1, 1990

By Bennett McLaughlin, Gille Brousseau, John F. Cook

"La Mine Bousquet commenced operations in October 1979. Mining has been by underground methods from two main zones which dip steeply to the south , Sub-level stoping methods with following fill are used.The orebody and immediate country rocks are sericitic and highly schistose. The intensity of schistosity varies significantly and poor ground conditions prevail, especially within the orebody,Initially few mining problems were encountered but in May 1981, significant damage occurred. A system of stabilizing pillars was introduced with improved support systems. Predevelopment in ore and pre-drilling of blastholes were reduced with extra footwall development.Damage has continued to occur on a regular basis particularly during the spring thaw. Generally, the adverse conditions have been successfully overcome.IntroductionMost of the mining problems that have been experienced at Bousquet have been caused by poor ground conditions . This pa per describes these conditions, considers the cause and describes the ways in which the conditions have been dealt with . Despite the problems, Bousquet is a successful operation which in 1983 produced 95,000 ozs of gold from 514,000 tons of ore."

Jan 1, 1985

By D. Kao, J. Gogal, S. Humphrey, T. Byrne, M. Davoodi

"High total and dissolved uranium values were noted in the process water at the Cigar Lake Operation (CLO) during early production start-up period, whereas significant levels of dissolved uranium had not been observed previously at similar operations. The excess dissolved uranium resulted in higher demands on the water treatment plant, along with higher operating costs, environmental risks and some unrealized revenue potential. A species balance indicated that uranium was leaching into solution in the grinding, dewatering, and storage circuits under normal operating conditions. Jet boring, water recycle, ball milling, and the use of Pachuca tanks for ore storage results in a highly oxidative environment, which is favourable to leaching.This paper will outline the testwork performed to identify the conditions under which the uranium leaches into solution and to determine required conditions for uranium precipitation. Maximum uranium leaching was found to occur under normal operating conditions (pH ranging from 7.0 to 8.5); testwork indicated that both lowering and raising the pH can significantly reduce the uranium leaching. Analytical results combined with the batch scale testwork indicate that the uranium solubility is associated with carbonate species in the ore. Uranium precipitation was maximized at pH values greater than 10.5 or less than 6, corresponding well to carbonate leaching and precipitation values from literature. Higher precipitation efficiencies were noted at high pH ranges.As a result of this work, a pH control system has been implemented in the Pachuca storage vessels and thickener prior to water treatment plant on a trial basis. Caustic soda is recommended for pH control due to ease of operation, economic viability and material requirements and downstream constraints."

Jan 1, 2016

By W. A. Plachner, Schiller E. A., S. P. Santiago

"The Monkman Coal Property is located in the Northeast Coal Block of British Columbia. It is divided into the Duke Mountain Block on the north east and the Dip Slope on the west. Together, these areas cover 39,503 ha of coal licences.The property is underlain by Jurassic and Lower Cretaceous marine and continental sedimentary rocks. Economic coal measures are contained within the Gates Formation. Exploration of the property began in the early I970s, with drilling commencing in 1975. To date, 255 holes have been drilled and nine adits have been driven to recover unoxidized coal samples.The property has a geological resource potential of 2.8 billion tonnes of medium and high-volatile bituminous coal. Medium-volatile bituminous reserves, totalling 68.9 million ROM tonnes at an over-all strip ratio of 6.3:1, have been identified in three pit areas in the Duke Mountain Block.Construction start-up will commence when sales contracts are arranged. The clean coal will be exported via the Ridley Island Terminal at Prince Rupert.IntroductionThe Monkman Coal Property is located in the Northeast Coal Block of British Columbia in the southern port ion of the Peace River Coalfield. The coal field encompasses a strike length of 250 km of Lower Cretaceous coal-bearing strata in which 13 companies have identified several billion tonnes of resources and several hundred million tonnes of reserves. Currently, two companies with contracts are in the construction phase, and are scheduled to produce coal by early 1984. Quintette Coal Ltd. has a contract with Japanese steel mills to supply annually 5.0 million tonnes of metallurgical and 1.5 million tonnes of thermal coal. Teck Corporation (Bullmoose property) has a contract to supply 1.7 million tonnes of metallurgical coal annually."

Jan 1, 1983

By J. C. Botham, T. D. Brown

"Coke is the most costly item in steelmaking via blast furnaces . Recent innovations in cokemaking have been directed toward reducing this cost while simultaneously improving coke quality and expanding the range of coals used in the process. It is also important to meet increasingly stringent environmental legislation.Improvements in coke quality have been achieved by novel blend selection procedures, by charge density control using both selective pulverization and partial briquetting, and by the use of modifying additives.The Canadian Carbonization Research Association provides a focus for Canadian cokemakin g research which has demonstrated these technologies in a series of pilot-scale experiments."

Jan 1, 1980