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By A. E. Gran

"QIT -Fer et Titane Inc. currently produces and markets four main products: a titania slag named SORELSLAG for the white pigment production, a high purity pig iron known as SOREL-METAL mainly used in the ductile iron casting industry, an ilmenite ore for blast furnace applications called SORELFLUX and high quality steel billets SORELSTEEL employed in the wire rod fabrication. Moreover , QIT also manufactures high quality iron and steel powders labeled ATOMET for the powder metallurgy industry through its wholly owned affiliate. Quebec Metal Powders Limited. The company operates. rock ilmenite mine near Havre St. Pierre and produces its slag and ferrous products from its metallurgical installations located in the Sorel/Tracy region. QIT. born in 1948 from a joint-venture between Kennecott Copper Corporation and New Jersey Zinc Company, was acquired from BP Minerals by RTZ Corporation PLC in 1989 and remains its wholly owned subsidiary ever since.lImenite is a mineral rich in both titanium and iron oxides. QIT's proprietary mineral enrichment and electric smelting processes permit the concentration of the ilmenite ore and the separation of its main constituents to produce a 80% TiO2, slag and a high purity molten iron which is further transformed into iron ingots (pigs), steel billets, iron and steel powders.QIT's ilmenite deposit is located in the Lake TIo-A1Iard area, 43 km inIand from Havre St. Pierre, a community on the north shore of the St. Lawrence River some 960 km from Montreal. The orebody, covering some 542 000 m2, consists primarily of coarse-grained ilmenite (FeO.TiO2) with disseminated fine lenses of hematite (Fe2O3). The worthless mineral (gangue) associated with ilmenite is mainly anorthosite, a complex silicate. QITs mining operations are carried out using conventional open pit methods in a 500 m by 600 m horse-shoe shaped mine with nine benches developed. Primary blasting is performed on a weekly basis during the mining season. Blasted ore is trucked to the crushing station to be broken down to 15 cm and 7.5 cm sizes, respectively, by means of a primary jaw crusher and a secondary cone crusher. Minus 7.S cm ilmenite is then loaded into hopper cars for the 43 km trip to the Havre St. Pierre terminal where it is stockpiled and reclaimed by under-ground conveyor chutes to a ship loading tower at the dock. The crushed ore is shipped to QIT's smelter located in Sorel in 40 000 tonne carriers from April to December."

Jan 1, 1995

By F. W. Gray

A GEOLOGICAL study seeking to determine, for economic purposes, the value of the Sydney coalfield as a source of coal supply. Limitations of the coalfield come under two main heads: (a) Areal extent of the undersea coalfield. (b) The distance from shore at which coal can be mined at a cost of production permitting its profitable sale. Conclusions reached are that the areal extent of seams below the Phalen seam is of. small economic importance, and that non-persistence of these seams in full thickness and quality in the undersea extension of the coalfield will put an end to profitable mining before any limitations connected with distance from the shore-line become operative. With respect to the Phalen seam, non-persistence or deterioration of the seam will become effective in the western part of the coalfield, and less certainly in the eastern part of the coalfield, before operation of limitations by distance from shore. In the central portion of the coalfield, the seam probably persists in commercially workable thickness and quality to beyond the limit of mining set by distance from the shore-line. With respect to the seams above the Phalen seam between the Mountain fault on the extreme western boundary of the coalfield and the assumed termination of the deposition area on the eastern extremity of the field near South Head of Morien, there appear to be only such limitations as arise from engineering approach, distance from shore, sufficiency of strata cover between the sea-floor and the upper coal seams, and quality of the coal (with certain reservations as to the continuity of the upper seams under Sydney harbour and in the Sydney Mines-Little Bras d'Or district). Some of these seams have fragmentary land outcroppings from which their persistence seaward is assumed, and there may be other and still higher seams in the strata column which are entirely submarine.

Jan 1, 1941

By M. B. McClenaghan

"Abstract - The Matheson area of northeastern Ontario is of great interest for mineral explo­ ration because of its geological similarities with the adjacent Timmins, Kirkland Lake and Larder Lake gold camps. Exploration in the area, however, is hampered by the presence of an extensive and thick cover of glacial sediments. For this reason, till geochemistry has be­ come an important exploration method. The Ontario Geological Survey&apos;s Black River -Matheson (BRiM) reconnaissance till sampling project, carried out between 1984 and 1988, was designed to aid exploration in the Matheson area by documenting the Quaternary stratigraphy and providing a database of till geochemistry. Till samples were collected by backhoe trenching of surface pits in areas of thin drift ( < 5 m) and by sonic overburden drilling in areas of thicker drift. This paper summarizes the results from the shallow till sampling component of the BRiM project.Two hundred and eighty-two surface samples were collected from Matheson Till, the youngest till sheet in the area, which was deposited during the Late Wisconsinan. For each sample, the non-magnetic heavy mineral (>3.3 S.G.) and fine (-250 mesh) till fractions were analyzed geochemically. In addition, visible gold grains were recovered by panning the heavy mineral fraction. Five areas that display multi-element anomalies in both till fractions warrant further investigation: (1) western Egan Township, overlying the Bradley Lake Syenite; (2) around and south of the Munro and Croesus mines, in Munro and Guibord townships; (3) central Garrison Township overlying the Garrison Stock; (4) south of Ore Car Lake in northern Thackeray Township; and (5) southeastern Harker Township. In these areas, Matheson Till has a local provenance and the bedrock sources for these anomalies are nearby in the up-ice (north­ northwest) direction. Due to the fine-grained nature of gold in bedrock deposits in the BRiM area, the small size of most gold grains recovered from till samples (<50 1-1m) and the variable distribution of gold in the heavy mineral concentrate and fine fractions, the fine fraction in addition to the more commonly used heavy mineral concentrate should be used for gold exploration.Surface till samples have been affected by weathering to a depth of s3 m. Weathered till is characterized by a very low carbonate content in the matrix fraction, the absence of sulfide grains in the heavy mineral concentrate and higher concentrations of copper, nickel and zinc in the fine fraction than in the heavy mineral concentrate. As a result of the weathered/ oxidized nature of the surface till samples, the fine fraction is a better sampling medium for base metal exploration."

Jan 1, 1992

By B. K. Gorain

"The Air-Metabisulfite (AMBS) process has been developed to treat complex copper, molybdenum and precious metals (gold, silver) bearing ores using brackish and sea water. This process was able to produce significantly better copper concentrate grades and higher recovery than possible using conventional lime and/or cyanide based processes for certain complex ores with high sulphide gangue minerals. The AMBS technology in now used commercially following a rigorous evaluation process emanating from laboratory curiosity to plant applications. In addition, many projects have embraced this technology at a feasibility level involving various complex ore bodies.This paper presents a summary of the findings from testing the AMBS technology on various ores types. Experiences gained from this successful development from bench to piloting and then to plant applications are also presented in this paper.INTRODUCTIONProcessing of sulphide copper, molybdenum and precious metal ores typically involves flotation of copper bearing minerals while depressing non-sulphide and other non-copper sulphide minerals such as pyrite, pyrrhotite and sometimes arsenopyrite. Though in many precious metal ores, the values are in these sulphide minerals as well. The conventional method employed in the industry to produce a saleable copper concentrate requires depression of these non-copper sulphide minerals using an alkaline pH above 9.5, though 10.5 to 11.5 is more common. Alkalinity is controlled by the addition of a pH modifier. Lime is normally employed as a pH modifier due to its relatively low cost; however, the costs associated with adding lime can be significant and the effectiveness of lime as a depressant could be drastically reduced when the process water supplied to the flotation circuit contains high level of dissolved salts. In some cases, a small amount of cyanide is used along with lime to depress non-copper sulphide minerals especially when its proportion to copper sulphide minerals in the ore is higher than three."

Jan 1, 2016

AGENDA ? Company Overview ? Industry Direction ? Technology to support maintenance ? data access, connectivity, process historian, downtime & production reporting. ? Case Studies Company Overview Corporate Offices Client Base ?16 consecutive years of growth & profitability ?#39 of Top 50 Control Companies (Worldwide) ?470 employees ?TSX: MTK Industry Direction Improved visibility into the business so they can: ? Reduce cost through better understanding of where costs are being incurred and making timely decisions. ? Optimize operations while leveraging existing assets. ? Have a single version of the ?truth? ? Deliver reliably to stakeholders on the demand for increased accountability (safety, environmental, regulatory performance etc?). ? Respond quicker to market conditions in order to out perform the competition ? Best in Class approach. Web is becoming the standard user interface.

Apr 1, 2005

By A. E. Flynn

THERE is at the present time a revived interest in amalgamation, due to the number of mines starting up, usually on high-grade ore, and utilizing this relatively cheap and convenient means of recovering gold, more especially in their initial stages of production. The marked increased use of the amalgamation process has revealed a dearth of amalgamators and there is no doubt the art of amalgamation has stood still for a generation or two and is not readily applicable to the modern practice of milling gold ores. Mill operators of long experience are learning the art for the first time and are giving it intelligent study, and considerable testing and research work is now being undertaken Most millmen consider amalgamation a simple process, and so it is when we have a clean ore with coarse gold, specially when stamps are used for crushing. In treating Nova Scotia ores by stamps and amalgamation, recoveries of 95 to 97 per cent are common and easily obtained. So-called &apos;under-water feed&apos; is almost universally used in Nova Scotia and is quite beneficial. The water is supplied through jets between the dies and below the die surface and maintains this space as a live trap which catches the gold particles before they are overground and spoilt for amalgamation. With this method, the portion of gold recovered in the battery is higher than usual and often amounts to 80 per cent of the total gold in the ore, the remaining 20 per cent being caught on the plate. As a continuous amalgamator, the simple plate cannot be excelled. Some of the modern devices having moving or covered and not very accessible plates, which cannot be readily inspected and dressed to keep them in condition, do not give the best results in service. An exception might be drawn in the case of amalgamation of very heavy ore or concentrate which would bank up unless the plate is carried at such a steep inclination as to weep mercury. Difficulties in stamp-mill amalgamation are encountered when acid water is used or when grease is present. Also, certain sulphides and graphitic and talcose ores give trouble, resulting in poor gold recovery and high mer-cury loss. The older literature on gold milling deals with the common troubles of this type and the old-time amalgamator was well able to take care of day-by-day difficulties. When the difficulties were unsurmountable, the ore was classed as &apos;refractory&apos; and other processes were used.

Jan 1, 1939

By L. A. Homeniuk, R. J. McH. Clark

"The Maurice Bay deposit, the Stewart Island showing, the Fond-du-Lac deposit, the Middle Lake showing and the Nisto deposit are located on the North Rim of the Athabasca Basin. They are probably unconformity-related. These occurrences tend to be small. The Fond-du-Lac and Maurice Bay deposits are the largest and contain 450,000 kg and 650,000 kg of U10 8 respectively.Pitchblende is the main uranium mineral of all the occurrences, except at Middle Lake where autunite predominates. A II of the deposits are overlain and partially hosted by the Manitou Falls Formation of the Athabasca Group, except the Nisto deposit which is entirely within basement rocks, and the Maurice Bay deposit which is partially within the basement and overlying the Fair Point Formation of the Athabasca Group.The North Rim deposits are considered to be genetically similar to the other unconformity-type deposits found in northern Saskatchewan. It is suggested that a mechanical concentration of uranium may have occurred in heavy mineral beach sand type placers. The stability of the uranium minerals may have been enhanced by special local conditions. The fossil placers, after hydrothermal alteration and enrichment, would form the apparently ""rootless"" occurrences of uranium found totally within the sandstones above the unconformity.IntroductionAt least five deposits and showings and one train of mineralized glacial erratics of unknown provenance have been located on the North Rim of the Athabasca Basin from Maurice Bay in the west to Black Lake in the east. Distributed over a distance of 250 km, (Fig. l), they occur near the edge of the Basin, and are probably unconformity-related. The following have been identified from west to east (Fig. 2): The Maurice Bay deposit, the Stewart Island showing, the Isle Brochet train, the Fond-du-Lac deposit, the Middle Lake showing, and the Nisto deposit."

Jan 1, 1986

By P. D. Waters

"Mineral deposits are where you find them; they have no allegiance to territorial boundaries. Over the past decade much of the new investment in mining has been outside of continental North America, let alone Canada. The larger Canadian Banks have pursued this offshore business through their multi-national organizations; this reflects both the increasingly international orientation of today&apos;s business environment, and to a degree, the competitive advantage of these offshore developments.The current oversupply situation in mineral markets and the increasing maturity of the Developed World Economy reduces the need for new mining projects relative to growth&apos; in GNP. Those that are brought on stream in the future due to their competitive advantage, will continue to be pursued by lenders and equity investors alike. IntroductionProspects facing those who search for mineral wealth were described rather well more than 200 years ago by a Scottish professor of moral philosophy, who also happens to be the father of modern economics.In search for new mines, Adam Smith wrote in The Wealth of Nations, ""there seems to be no certain limits either to the possible success or to the possible disappointment of human industry"".How true that statement remains today, where we are seeing economic cyclical problems compounded by basic fundamental structural change within the mining industry.Despite the enormous advances in earth sciences during the past two centuries, the rewards of mineral exploration still remain uncertain. Even though a promising orebody is found, ultimate profitability may still depend on the vagaries of the marketplace, where large and unanticipated changes in supply, demand and prices can play havoc with the best of calculations.The Canadian mining industry has had its share of disappointment during the past few years, with savage competition, shrinking demand, declining prices, and disappearing profits. But it has also had some share of success, such as at Hernlo, which now seems certain to provide some of the lowest cost gold production in the world"

Jan 1, 1986

By A. Romero

"Most underground mines require heating or cooling systems to meet health and safety standards in the working areas. In regions where daily or seasonal fluctuations of environmental conditions exist, these systems tend to be over-sized and operate at low average load factors, which increase both investment and operating costs. One possible approach to reduce the temperature variations of the fresh air supplied to the mine, and so reducing the investment in large heating or cooling systems, is to use rock as a thermal regenerator or thermal storage system. Packed rock beds act as thermal inertial units, damping the atmospheric temperature oscillations to provide a more constant fresh air temperature. However, although regenerators exist in some mines, and packed bed rocks have been studied in detail in solar thermal power applications, there is a lack of tools to design new and sufficiently large storage systems of this kind. This work fills the existing gap by presenting a methodology to design and evaluate the impact on the ventilation systems of these regenerators. The method is validated using existing rock bed systems found in the literature and illustrates possible designs for small and large size regenerators in both hot and cold climates.1 INTRODUCTION “ It is quite amazing how often answers to extremely complicated problems can be obtained in this way, by using greatly simplified models of the real situation for the purpose of calculation.” Whiller, A. in private communication to J. S. Stachulak (1989). Motivation Most underground mines located in regions with extreme climatic conditions require the thermal pre-treatment of the fresh ventilation airflows, whether for heating or cooling. Heating commonly is needed in sites with sub-zero temperatures and is usually effected by direct or indirect burning of natural gas or propane. Alternatively, cooling is required in areas with hot temperatures, or in mines with high underground thermal loads where the fresh air at ambient temperature cannot provide enough refrigeration. Thus, when the ambient air conditions cannot provide by itself enough thermal power to ensure safe underground working conditions, a heating or cooling plant is required, which involves a considerable equipment and operation cost."

Jan 1, 2019

By G. J. Heferen, A. Pranowo, N. J. Aslin, P. O. Eriksson

Glencore Technology (GT) has over four decades experience supplying stainless steel cathode plates (“cathode plates”) to the electro-refining and electro-winning industry. Cathode plates are typically the single biggest capital investment in a refinery. Refineries may view cathode plates as fixed asset or consumables depending on their operational characteristics. This paper examines the issue of cathode plate life and the strategies and philosophies used by different plants in the management of their cathode plate asset. Some plants operate with their original plates after more than 20 years. Others accept high turnover and regular maintenance as normal operating practice. Reference data are provided on plate life for various operating plants including benchmark plants achieving best-practice plate life and operating cost. The role of the electrode handling equipment on cathode plate longevity is also examined, including latest developments in Cathode Stripping Machine, robotic copper stripping, and full-automation production cranes. The ability to identify and manage the population of plates in service is also critical for maximising plate life and minimising its overall operating cost. This paper discusses a novel and unique RFID system for tracking and managing cathode plate inventory. INTRODUCTION Permanent cathode plates The adoption of permanent stainless steel cathode electrodes in the electro-refining of copper was the most significant process development since the first commercial electro-refineries were built in the late 19th century. It provided significant improvement over the labour intensive and complicated starter sheet system. Copper grows over the permanent cathode blade for a number of days before being stripped, and the permanent cathode can be returned straight back to cells for the next cathode cycle. Glencore Technology (formerly Mount Isa Mines (MIM), then Xstrata Technology) has been manufacturing permanent stainless steel cathode plates from the late 1970s with the birth of ISA PROCESS™, and the Kidd process that came one decade later. Invented and commercialised by Mount Isa Mines, the ISA PROCESS™ was first implemented into Copper Refineries Limited (CRL), Townsville, in 1978. The KIDD PROCESS by Falconbridge evolved in the 1980s and was first implemented into the Kidd Creek Tankhouse, both operations converting from traditional copper starter sheets.

Jan 1, 2019

By A. G. Roach

Introduction The plant described in this paper is located at Coniston, Ontario, the smelting centre of the former Mond Nickel Company. Coniston is situated some eight miles east of Sudbury on the main line of the Canadian Pacific railway and on the Toronto-Capreol branch of the Canadian National-railways. The plant is now under control of the International Nickel Company, as a result of the merger of the two companies in 1929. The smelter proper includes four 50-in. by 240-in. blast furnaces and five 13 ft. by 30 ft. converters, and has a capacity of about 65,000 tons of ore charge per month. As accessories to the smelter there are a mill, where some 10,000 tons per month of low-grade ores are concentrated, and the sintering plant, which is the subject of this paper. The present 6-unit sintering plant replaces a former 4-unit installation. Here, fine ores, concentrates, and flue-dust are sintered on Dwight-Lloyd machines, the sinter produced being charged into the blast furnaces. At the time of writing (1931), only the concentrator is operating at capacity, due to present world conditions.

Jan 1, 1932

By Pierre O'Dowd

"The southern Abitibi Belt is the major source of gold in Quebec. Although the northern part of the belt is quickly being developed, the area under study will not be downgraded in the near future because it still contains more than 75% of the known reserves in the belt.Gold is found in a variety of geological environments which are part of a small number of distinct structural patterns. For the exploration geologist, outlining such patterns might be easier and more productive than defining, when it is possible, the exact genetic nature of the gold mineralization.Exploring in the right place has always been one of the main concerns of explorationists. This paper briefly describes the various favourable geological settings, and outlines areas, types of structure and lithologies of high potential for gold exploration in the southern Abitibi Belt.IntroductionThe southern part of the Abitibi Belt is a profilic mining area for precious and base metals (Lulin 1990). Although mineralizing processes and controls of polymetallic deposits are well known and understood (Lydon 1984), almost every gold occurrence is a unique case and numerous models have been proposed (Roberts 1987; Hodgson and McGeehan 1982; Hodgson 1990).This study does not define new genetic models for the formation of gold deposits, neither is it meant to elaborate on the existing ones. A genetic approach, is by definition, theoretical and, to some extent, universal. It helps geologists define types of targets and exploration tools but does not outline or quantify target areas. To tentatively summarize the complexity of a genetic approach, a brief discussion on the various genetic models in vogue in Abitibi and the problems related to their use in exploration can be found at the end of this paper."

Jan 1, 1991

By A. McLean, M. Barati

In this paper, examples are presented of pyrometallurgical research and associated teaching activities during the past century within the Department of Metallurgical Engineering, now the Department of Materials Science and Engineering, at the University of Toronto. Throughout these years, pyrometallurgical research has been characterized by recognition of the importance of the interdependence of measurements and models as well as the development and application of sensors, for the generation, validation and practical implementation of new knowledge. The important role played in the delivery of lectures and participation in joint research by Adjunct Professors with strong backgrounds in the pyrometallurgical industry is described. Projects conducted in close collaboration with the industrial sector and opportunities for students to obtain practical experience working as teams on a "round-the clock" shift basis within an industrial pilot plant environment are outlined. These activities, together with the involvement of students in poster competitions and the presentation of papers at society conferences and technical meetings, are still vital elements in the development of pyrometallurgists equipped with the appropriate professional skills for subsequent employment within academia, government laboratories or the industrial sector.

Jan 1, 2015

By Ian E. Efford

The paper gives an assessment of Canada&apos;s energy supply-and-demand position, the current situation and projections into the future, as well as a review of some alternative energy futures for Canada. The main elements of Canada&apos;s energy strategy for the period 1977-1990, with particular reference to the role of energy conservation, are discussed, leading in to the development of the national energy conservation program.

Jan 1, 1977

By Jehan Rondot

Des quartzites très pars ont été dêcouverts au cours de la cartographie de la region du lac des Martres, étape de l&apos;étude géologique de la region de Charlevoix. On distingue quatre groupes métasédimentaires, tons con tenant des niveaux de quartzite dans an moins deux domaines géologiques différents, c&apos;est à l&apos;ouest, clans le domaine gneisso-charnockitique que se situent les quartzites du groupe des Martres. Quartzite et gneiss à grenat et sillimanite, en banes épais, constituent la formation de La Galette. A Pest, dans un environnement gneisso-granitique, les deux groupes métasédimentaires de Saint-Siméon, et de La Malbaie comprennent, par contraste, des bancs pen épais et de compositions variées. Les niveaux de quartzite dépassent rarement 50 m d&apos;épaisseur. L&apos;autre groupe metasédimentaire, celui de Saint-Tite des Caps, recoupé de nombreuses intrusions charnockitiques et granitiques, ne possède que de minces niveaux de quartzite. La pureté et la grande épaisseur des quartzites de La Galette suppose une histoire complexe qui se termine par des depots continentaux de climat aride, par opposition aux depots marins des autres groupes. D&apos;autre part, la presence de ces quartzites an sein de roches Presque anhy¬dres et de haute temperature que sont les charnockites leur confère des caractéristiques de fusion sans decrepitation. Parmi la multitude de depots de quartzite qui existe clans le monde, peu sont de qualité supérieure. Or, de par sa composition chimique, le quartzite de La Galette se compare avantageusement à ceux des meilleurs gisements des Etats-Unis, de l&apos;Europe de l&apos;Ouest et de l&apos;Afrique du Sud. D&apos;accès facile pour l&apos;exploitation, les gisements ne sont qu&apos;à une trentaine de milles de Baie Saint-Paul ou de La Malbaie, sur le Saint-Laurent. L&apos;utilisation en metallurgic prévue pour le quartzite de La Galette comprend la production de silicium, de ferro¬silicium et d&apos;autres alliages de silicium. La composition du quartzite est en outre appropriée pour la production de carbure de silicium et de silicate de sodium. Les fines peu¬vent être utilisées pour la fabrication du verre et comme matière de charge.

Jan 1, 1977

By G. W. H. Norman

"The La Corne molybdenite-bearing veins, discovered in 1915, lie halfway between Amos and Val d'Or near the southwest corner of La Corne township, Abitibi county, Quebec. The Molybdenite Reduction Company, which carried on operations during 1927 to 1930, sank a 200-foot inclined shaft to develop the property and produced about 22 tons of concentrntes from a 30-ton mill during 1929. Hollinger Consolidated Gold Mines, Limited, carried on further underground exploration in 1930. The Molybdenite Corporation of Canada drilled a part of the property in 1938 to 1939 and produced 1 ton of concentrates in 1938. Wartime Metals operated the property from 1942 to July 15, 1945. At this time the mill was enlarged to treat 200 tons daily. Molybdenite Corporation of Canada since July 15th, 1945, have continued the operation of this property and have revised the mill flow-sheet in order to produce both a bismuth and a molybdenite concentrate.The production for the period 1942-1946 is as follows:Total molybdenite production from the mine in the 1942 to 1946 period was about 4,127,400 lb.The La Corne deposit occurs at the northwest contact of a small mass of biotite granite with biotite schist. The form and extent of the biotite granite mass is concealed by a wide sand plain that extends northwest and west from the deposit and overlies bed-rock except in four small outcrop areas. These are spaced 1,000 and 2,000 feet apart along a narrow strip extending 5,000 feet south from the mine. The outcrops suggest that the granite must be at least 1,500 feet wide and 3,000 feet long northeastward. Where exposed in the mine workings the contact dips 70°N.W., but is not a sharply defineable feature due to the presence of numerous granite dykes and tongues in a zone of biotite schist 100 feet wide along the margin of the granite. The biotite schist in the few outcrops that flank the north and south sides of the granite strikes northeast and dips 60° to 70° S.E."

Jan 1, 1954

By Warwick Bullen

A hypothetical economic model has been developed for diamond projects in the Canadian Arctic using data from recent exploration and mining projects. The model reflects economic conditions as it applies to the diamond mining industry in the Canadian Arctic at the present time. The economic model captures pre-production expenditures, production data, and post-production costs. Before- and after-tax cash flows are derived from the data along with the relevant economic criteria. From the corporate perspective, the model provides guidance as to the minimum size and/or in-situ value per tonne requirements of targets being sought in order to ensure economic success and probable exploration and development expenditures. From the government perspective, the model provides an indication of income and mining tax revenues that can be expected from a particular diamond project. The model shows, on average, diamond projects in the Canadian Arctic are expensive to explore for and develop, but are economically robust. They generate great economic return for mining companies and significant amounts of tax revenue for governments. The fact that diamonds can be transported directly from the mine site by air makes them particularly attractive targets for mining companies that operate in the Canadian Arctic.

Apr 1, 2005

By A. Warczok

The computer simulator of slag cleaning in an electric furnace is based on a set of mathematical models describing heat liberation, the rate of slag reduction and gravitational coalescence of matte and metallic copper inclusions. The simulator consists of a mass and heat balances as a frame, in which the kinetic equations of the slag reduction and phase separation are incorporated. Friendly user-screen interface allows for dynamic control of process parameters in real time together with simulation of typical operations, such as furnace charging with liquid slag, solid reverts and coke, tapping out of the slag and matte, motion of electrodes and control of the transformer. The batch, semi-continuous or continuous process can be simulated. The process parameters are displayed and continuously recorded for further analysis. The computer simulator is a powerful tool for process optimization, training of furnace operators and the design of new slag cleaning installations.

Jan 1, 2007

By S. N. Dixon

"Maximizing the value of each tonne of processed ore is the goal for all operations. Cyanidation processing of gold-copper ores has been challenging since its first use in 1889. The current practice treats a bleed or the total flow of mill solution to recover copper as copper sulfide (by sulfidization, acidification, recycling, and thickening), or to recover the cyanide (by acidification-volatilizationneutralization). The process presented uses the adsorption of copper cyanide by carbon and the selective elution of copper from carbon to concentrate copper into a smaller stream. Copper contained in the smaller stream is precipitated as copper cyanide.RÉSUMÉ Toutes les exploitations ont pour objectif commun d’optimiser la valeur de chaque tonne de minerai traité. Depuis sa première utilisation en 1889, la méthode de traitement par cyanuration des minerais aurifère et cuprifère s’est révélée complexe. La pratique actuelle traite la saignée ou le débit total d’une solution de traitement du concentrateur pour récupérer le cuivre sous la forme de sulfure de cuivre (par sulfuration, acidification, recyclage et épaississement), ou pour récupérer le cyanure (par acidification, volatilisation et neutralisation). Le procédé présenté dans cet article utilise l’adsorption sur charbon actif de la solution de cyanure de cuivre et l’élution sélective du cuivre depuis le charbon pour concentrer le cuivre en un plus petit jet. Le cuivre contenu dans ce plus petit jet est précipité sous forme de cyanure de cuivre."

Jan 1, 2017

By Ham. Y. M.

The corrosion behaviour of Al-B4C metal matrix composites immersed in 2500 ppm boron-containing H3B03, 0.5 M K2SO4, and 3.5% NaC1 solutions was investigated. Effects of B4C particle volume fraction on the corrosion behaviour of composites were studied using potentiodynamic polarization and electrochemical impedance spectroscopy techniques. Scanning electron microscopy was employed to study the surface morphology of the material before and after corrosion. Results show that all materials investigated are more corrosion resistant in 2500 ppm boron-containing H3B03 than in other solutions. No appreciable corrosion was observed in boric acid and sulfate solutions in contrast to an obvious pitting in NaC1 solution for both base alloy and composites. The preferential pitting sites are the interfaces of Al/Fe intermetallics for the base alloy, and the A1/B4C interfaces for the composites. Increasing the volume fraction of B4C particles in the composite decreases its corrosion resistance of Al-B4C composites.

Jan 1, 2011