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By S. V. Ulianov, A. Y. Senchenko, E. M. Kurchevskaya

"A process sample of old copper-containing tailings (-2.0+0 mm) from an iron-ore plant was tested in TOMS institute in order to develop a process for copper concentrate production. The study of tailings material composition indicated that -0.2+0 mm fraction was efficient and contained 97.26% of copper. Copper is predominantly concentrated in chalcopyrite which is present both in free form and in intergrowth with ore and rock-forming minerals. Study of chalcopyrite using an optical microscope and Qemscan SEM determined that the most grains surface was covered with oxide films. Additionally, a lot of grains had micropores on their surfaces that indicated a partial mineral leaching. The oxide films did not make it possible to float copper minerals from head material. It was recommended to apply an attrition operation to restore chalcopyrite floatability. In order to increase selectivity a regrinding stage for a primary copper concentrate was introduced to obtain P80 26 um. Taking these recommendations into account a flotation flowsheet was developed to process the old Cu-containing tailings. The flowsheet allowed us to obtain a concentrate with 23.5% Cu content at 71.5% recovery.INTRODUCTIONStudy of material composition is an important prerequisite for development of a minerals processing technology. Mineralogical study contributes to search for an efficient technology to recover valuables and for prospective methods of minerals processing.The use of such up-to-date analysis methods and equipment as Qemscan and Mineral-C7 allows one to determine minerals size, liberation degree, and mineral associations. Mineralogical data can reveal reasons for hard processing of minerals prior to development of the process.The advanced process mineralogical methods used to study Cu-bearing pond tailings indicated several factors that influenced development of the process. The first one is a barren size fraction which is to be removed from the process in order to considerably reduce the costs connected with grinding. The second is the presence of films on chalcopyrite surface; in this context, a preliminary attrition of the material was recommended. The third factor is finely disseminated Cu minerals in sulphide and in the rock, which predetermined selection of particle size for flotation. All these data led to significant decrease in time required to develop the process technology. The developed process flowsheet based on the obtained mineralogical data is present in Figure 1."

Jan 1, 2016

By Michelia Alba, Ronaldo S. Sampaio, Davi S. Braga, Mathieu Dubé

Climate change is pressuring industries and governments for decarbonization commitments, research, testing, and use of best practices to achieve the target of global warming below 1.5/2 °C. As it accounts for as much as 7% of all global CO2 emissions and 7% of energy consumption, the steel sector needs to address this issue with extended efforts. This paper provides information on the key potential of renewable biochar as an alternative fuel for pellet production. It also summarizes the successful application of biochar in a pioneering case study as the main fuel for a Grate-kiln pellet plant in Brazil, as well as the study of its use to replace coke and anthracite as an additive for iron ore pellets and other possible applications in the steel industry in COREM's precompetitive research & innovation program. The final discussion reveals the large quantity of biochar required by the Brazilian and Quebec scenarios for reducing CO2 emissions of iron ore pelletizing plants.

Jan 1, 2023

By H. Fuchs, W. Hilger, E. Prosser

"The Lone Gull discovery of Urangesellschaft Canada Limited was made in 1974 as a result of extensive exploration activities for unconformity related uranium deposits in the Baker Lake area of the Northwest Territories. The structurally controlled mineralization is hosted in Aphebian metasediments and intrusive granitic stocks located approximately 2 km south of the unconformity between the Lower Proterozoic Aphebian and the Middle Proterozoic The/on Formation.The original discovery was made with a helicopter mounted radiometric system during systematic prospection over the unconformity. Diamond drilling was first carried out in 1977 and continued, with an interruption in 1981, to the present. A total of 25,500 metres and 199 holes have been drilled and outlined three ore zones. Preliminary geological reserves are estimated at some 16 million kgs. U30 8 at an average grade of approximately 0.4%.IntroductionUrangesellschaft initially entered exploration in Canada as a participant in joint ventures in 1968, and was incorporated in Canada in 1974 as Urangesellschaft Canada Limited. Subsequently, UG was among the first companies to apply exploration criteria developed from the Athabasca Basin, namely the Middle Proterozoic unconformity over Archean/ Aphebian basement, for selection of exploration targets in the geologically similar Thelon Basin.The Baker Lake area in the Keewatin District of the Northwest Territories was selected from the extensive Thelon Basin because it had the best accessibility (Fig. 1). The hamlet of Baker Lake located close to the geographical centre of Canada, is largely an Inuit settlement with a population of approximately 1,100 inhabitants. The distance from Baker Lake to the Lone Gull property is about 80 km. Baker Lake is connected to the tidewater of Hudson's Bay via Chesterfield inlet and is serviced by scheduled domestic flights several times weekly from Churchill, Manitoba, about 650 km to the south."

Jan 1, 1986

By J. L. Bowlby

The heats of combustion of fuels are determined in the laboratory by means of a calorimeter, usually of the oxygen bomb type. A known weight of the fuel is burned in an atmosphere of oxygen under approximately 400 pounds pressure in a heavy metal container-the bomb- and the heat evolved is imparted to a definite quantity of water. From the rise in temperature, measured by means of a Beckmann thermometer, and other data incidental to the determination, the heat value of the sample can be calculated. On paper, the method appears simple indeed, but in practice the determination of the heat of combustion is one of the most difficult of the various coal analyses. This h as led to considerable investigational work in order to obtain formula: whereby calorific values of solid fuels could be calculated from proximate analysis data al one. The proximate analysis of a fuel consists of the determination of moisture, ash, and volatile matter, with fixed carbon by difference. Sulphur determinations properly belong to the ultimate analysis, but in this section of the country, where the sulphur content of the coal is comparatively high, a request for the proximate analysis of a fuel implies the determination of the sulphur as well.

Jan 1, 1929

By D. Pawelus, J. Butra, R. Debkowski, M. Szpak

Impact of horizontal stresses on stability of underground workings in mines is a very important issue in underground mining. Identification of the initial state of stress in the rock-mass should be one of the main actions taken into account while designing and carrying out the mining activity in underground mines. The paper presents the tests on three dimensional stress pattern in Polish copper mines, owned by KGHM Polska Miedz S.A. Group, carried out in 2012. The research program covered 7 measuring stands in two mines; their average depth was about 1000 m. The main aim was to identify the values and directions of horizontal stresses in order to optimize the extraction and to improve the safety. The overcoring method with the use of CSIRO HI type probe was applied. The paper also describes the measuring technique which was developed for the purpose of specific mining and geological conditions of KGHM mines, taking into consideration the natural hazards encountered there as well as technical and operational capabilities with regard to drilling equipment. The experience gained during the underground measurements and the issue of making such measurements in underground copper mines in Poland are presented in the paper. The stress patterns obtained during the underground measurements are of application importance for the process of designing the spacing of mine workings and improving their stability and mine support selection.

Jan 1, 2015

By J. S. DeLury

The last few years have been eventful ones for Manitoba in connection with mineral development. Perhaps the past year has been the most important of all. It is therefore a suitable time to review the mining situation in the Province. In order to obtain, in the following paper, a proper set ting from which to discuss the trend of recent developments, a brief review of the story of mining will first be given. This will include a summary of a few of the outstanding facts regarding prospecting, discovery, and operations in the several known metalliferous areas of the Province. Following this will come a more detailed description of activities during the past year or two. Special attention will then be paid to the outstanding enterprises, such a~ those associated with the names of Flin Flon, Sherritt-Gordon, and Central Manitoba, names which have been attracting the attention of the mining world to Manitoba. And last of all will be presented a brief summary of mineral production, which, so far, has largely been credited to non-metallics. HISTORICAL To aid a proper comprehension of the recent trend in mining, it is well not to lose sight of the history of development in the different metalliferous areas in Manitoba. This Province seems throughout to have been more or less dependent on mining interest excited by discoveries in the neighbouring province of Ontario. The first interest came as an effect of the Lake of the Woods mining boom, when small adjacent parts of Manitoba were prospected. Several discoveries were made, but no mining industry resulted.

Jan 1, 1929

By D. G. Sinclair

In any discussion on the subject of mine-safety, it is well to honestly face the fact at the outset that mining is a hazardous occupation and that certain inherent dangers attach to the work, which, in spite of the greatest vigilance on the part of everyone concerned, will from time to time exact their toll of in jury or death from the underground worker. Great progress has been made of late years in narrowing down the range of these necessary risks, and, illustrative of what can be done along these lines by concerted effort, it is pleasing to read from time to time of large operating mines running for weeks, months, a year or more, without a single lost-time accident. To achieve any results in the work of accident prevention it is necessary, first, to have a definite goal, such as a no-accident period, be it a week, a month, or a year, to aim at; and, second, to set up definite standards to work by. The legal code of regulations should form the basis of all standards of work at every mine and should, for this reason, cover as far as possible all conceivable phases of operation. This represents the ideal, but in practice it is unattainable, largely because of the many variables that must be considered, due to the divergence in the scale of operations and to differing geological conditions at the different mines. Hence it becomes necessary for the operator who wishes to attain the maximum in the establishment of high standards of safe operation to so amplify the code as to meet the peculiar requirements of his operation.

Jan 1, 1930

By L. Price, R. Hortie

Movement of ore and waste from the Hilton Mines pit is accomplished by truck haulage. With the aim of reducing costs, a study of truck fleet replacement was initiated. The study included on-site short-term tests and longer-term rental purchase agreements for haulage trucks. The operation and maintenance characteristics of different trucks, along with projected haulage conditions, were used to prepare cash flows, from which the most advantageous trucks were selected. The results of the study and implementation of the recommendations gave a cost saving greater than had been estimated. The study also indicated areas where improvements could be made, and resulted in much more attention being paid to road conditions, the training of operators and mechanics, and the development of a practical preventative maintenance scheme.

Jan 1, 1971

By R. L. Brown, E. A. Swanson

THE Buchans ore bodies are located in central Newfoundland, three miles north of Red Indian lake. The townsite of Buchans was named after a Royal Navy Captain who, while attempting to make contact with the Beothuck Indians, camped in the area in 1820. Ore was first found at Buchans by a Mic Mac Indian, Matty Mitchell, who discovered one of the three small orebodies in the bed of the Buchans river. The Anglo-Newfoundland Development Company, which holds mineral rights in the area, developed the orebody, but was forced to give up the venture because of difficulties encountered in separating the various sulphides. The American Smelting and Re-fining Company developed a flotation process which was capable of economically separating and concentrating the various sulphides, and, in 1926, they took a long-term lease on the property.

Jan 1, 1962

By W. E. Roscoe

"Mineral exploration properties are those on which an economically viable mineral deposit has not yet been discovered. Such properties are bought, sold, optioned and joint ventured on the basis of their perceived potential for the existence and discovery of a viable mineral deposit. The intrinsic value of an exploration property is therefore based on the exploration potential. One measure of the exploration potential is the amount that can be justified to spend on exploration for a viable deposit.The appraised value method uses a cost approach to value exploration properties. It is based on the premise that an exploration property is worth the meaningful past exploration expenditures plus warranted future costs to test remaining exploration potential. Results of past exploration work are analyzed in order to retain only those past expenditures that are productive in terms of identifying remaining potential. Warranted future costs comprise a reasonable exploration budget to test that potential."

Jan 1, 2002

By D. Gorc, T. M. Fraser, Z. T. Nikic, R. Pesalj

"Mount Polley is an alkalic porphyry copper-gold deposit of Lower Jurassic age within the Quesnel terrane in south-central British Columbia. The silica-saturated Mount Polley intmsive complex is assumed to be coeval with volcanic rocks of similar composition in the Nicola Group in which it was emplaced. Other intmsions and some of the volcanic rocks in the Mount Polley area are silicaundersaturated and contain feldspathoids.The Mount Polley deposit is characterized by multiple intrusions that vary from diorite to crowded plagioclase porphyry to monzonite. Intmsion breccias are associated with some of the intmsive phases. Abundant hydrothermal breccias occur on the margins and above plagioclase porphyry intmsions. These breccias provide the main host for mineralization and are associated with the highest concentrations of copper and gold. The breccias are subdivided into four distinct types based on the dominant hydrothermal mineral in the matrix. Actinolite breccia is developed in an elongate zone within the core of the Central zone and grades laterally and vertically into biotite breccia to the southeast. Magnetite breccia is irregularly distributed and is relatively sparse throughout the deposit and albite breccia is dominant in the West zone. Pervasive and vein-related alteration correlates with the breccia types. The core of the hydrothermal system at Mount Polley is subdivided into three zones: actinolite, biotite and K-feldspar-albite. The margins of the core zone are overprinted by a discontinuous zone of calc-silicate minerals. This intermediate zone passes outward into propylitic alteration. Mineralization is most prominent within hydrothermal breccias and is generally present as disseminations, blebs within the matrix and abundant veins. Mineralization is associated with a chalcopyrite-magnetite-bornite assemblage in the core of the deposit passing out into magnetite-pyrite-chalcopyrite. Relatively constant copper to gold ratios suggest that both metals were precipitated under similar conditions.Hydrothermal breccias are genetically related to the emplacement of the crowded plagioclase porphyry melt. Crystallization of the melt was probably accompanied by volatile/aqueous exsolution, forming a water saturated carapace. Decompression of the chamber in response to magma withdrawal, fracture propagation and possible fault movement allowed hydrothermal brecciation to occur at the apex and margins of the intmsion. Alteration and mineralization appears to have been controlled by fluids migrating away from the plagioclase porphyry."

Jan 1, 1995

By D. Vanin

"Conventional single heading track drifting in the hard rock mining industry has not shown any significant improvements in advance rates, despite the advent of modern track jumbos and igh speed muck handling systems .This paper presents Kiena 's experience in using a 7 ft 2 in. diameter larva Mark 6 Tunnel-Boring Machine (TBM) for driving 6000ft of drift.IntroductionKiena Gold Mines is located about 5 miles west of the town of Val d'Or, Quebec, approximately 300 miles north of Montreal. The mine commenced production in October 1981 and has gone through various expansions of ore production with 287 916 metric tonnes in 1982 to reach 453 800 metric tonnes in 1986.Due to the majority of claims being covered by a lake, a grassroots exploration drive of remote areas of the property was required to allow diamond drilling on a yearly basis. High speed sequential excavation methods (SEM) of single heading drifting in the mining industry has not progressed much in the past 20 years despite the advent of electric-hydraulic jumbos, Haggloader and Hagglund type cars. Certain examples of record SEM drifting advances have been performed in the past but only under very specific ground and cost conditions."

Jan 1, 1987

By T. W. Wloder

During recent studies concerning the effects that various surface treatments, surface imperfections, locked-in residual stresses and metallurgical and geometrical notches have upon the mechanical behaviour of metals and, in particular, upon their tension-bending characteristics under impact loads, it became apparent that specially developed methods and samples would be of great assistance in determining the desired data. This paper describes and discusses a number of different types of double-notched tension-bending impact samples which have been considered and examined for this purpose. The types most suitable for exploratory investigations are proposed for application in the study of the _behaviour of metals, their welds, and, in particular, their surfaces, when subjected to various notch-severities, surface imperfections, strain rates, temperatures, and constrained states of stress (i.e. the relations of the three principal stresses). It is expected that the proposed double-notched tension-bending samples and the proposed test methods will also contribute toward further understanding of the cold brittle behaviour and the notch-sensitivities of metals. The possibilities of introducing the so-called impact notch-sensitivity index and relative impact notch sensitivity of metals are discussed. Data obtained on double-

Jan 1, 1961

By G. E. Norman, A. L. Mckague

"The new smelting process commenced operation in 1978. The pelletizing and sinter plants were replaced with slurry-fed roasters and the blast furnaces with electric furnaces. The existing converter aisle and matte handling facilities remained unchanged.Process DescriptionNickel-copper concentrate is partially roasted in two slurry-fed fluid bed roasters. After gas cleaning, the sulphur dioxide gas is transferred to the acid plant. The roaster product is conveyed to two electric furnaces for smelting to produce a waste slag and furnace matte. The slag goes to the disposal area and furnace matte containing the metal values is processed in the converters for further removal of iron and sulphur.The final matte containing about 75 per cent metal values is shipped to the refinery in Norway.The commercial smelter was designed for 2135 tonnes per day of concentrate, with an availability of 85% . Roasters and electric furnaces were sized at 117 per cent of design, or 1250 tonnes per day on each of two lines. Concentrate storage capacity in the plant is sufficient for two to three days' plant operation.The new smelting process will be discussed under the following headings:Concentrate Slurry HandlingFeed PreparationRoaster OperationRoaster Gas CleaningCalcine TransferElectric Furnace Operation and Process Control Converting and Matte HandlingUnder these headings, process control , equipment changes, and plant performance after three years' operation is reviewed. A brief discussion of accident prevention , and working environment is also included ."

Jan 1, 1984

By J. L. Bowlby

Introduction In the following discussion, boiler-feed and mine waters will be considered from the point of view of the problems arising from the chemical nature of the mineral and gaseous impurities they contain. The theories underlying some of these problems will be reviewed for the purpose of getting a clearer concept of the problems themselves. Certain terms of a chemical nature, necessary to the discussion, will be explained on the assumption that they are not generally familiar to mining engineers. Finally, an attempt will be made to correlate theory and practice, with the abject of establishing certain limits to factors relevant to the problems, and to show that these limits are justified by practical experience. The general problems occasioned by the presence of mineral and gaseous impurities in boiler-feed and mine waters are: (1) Scale formation and corrosion in boiler systems. (2) Corrosion of mine pumps and pump fittings. These will be discussed separately. Boiler Scale Typical analyses of waters available for use in steam power-plants are given in the accompanying Table (Table I). All analytical data are expressed in grains per Imperial gallon. The bicarbonates of calcium and magnesium in the raw waters are shown as normal carbonates in the Table. Substances in the first five rows constitute the encrusting solids. All the waters listed in Table I would be classified as 'very good' in the schedule of classification for boiler waters adopted by the American Association of Railway Chemists in 1887. In spite of this classification, however, the waters contain sufficient encrusting solids to cause serious scale trouble after prolonged evaporation.

Jan 1, 1934

By N Robb

This paper gives an account of the laboratory testing, plant testing and final inclusion of the two-stage sulphuric acid leaching process in the Milliken mill. Operational results for September, 1962, are presented, showing a uranium extraction of 95.5 per cent, with a saving of some 16 lbs. of 100 per cent H~S04 and some 9 lbs. of lime per ton milled. Methods for effecting further improvements in the process are indicated. HISTORY P RIOR to the incorporation of two-stage leaching, the process for the treatment of uranium ores at Milliken consisted of a single-stage sulphuric acid leach, followed by a solution recovery step involving washing in thickeners and two-stage filtration. The thickener overflow solution was subsequently concentrated and purified by ion exchange, and the uranium was recovered, by two-stage precipitation, as ammonium diuranate. Figure I illustrates this flowsheet. For satisfactory extraction of uranium from the. Milliken ore, a high residual acidity, of the order of 40 grams per litre of free acid in the discharge solution, must be

Jan 1, 1963

By Malcolm Scoble, Nick Vagenas, Greg Baiden

Recent advances in underground communications technology have demonstrated the feasibility of teleoperation and automation in underground metal mines. One major challenge lies in the automation of underground mobile machines from surface, with the potential to reduce significantly the need for human involvement in underground operations. This paper reviews the evolution of underground metal mining automation, principally related to the development of teleoperation and automation of mobile mining machines. Examples of prototype systems are given and the associated benefits that have been observed are reviewed.

Jan 1, 1997

By Oliver Hall

This paper sketches the mining at Noranda as it would be sketched to a visiting engineer. It does not follow quite the usual form, but is presented somewhat along the lines of a conversation. TO give the mining at Noranda its proper perspective, it is necessary to sketch the whole picture and outline: 1. History 2. Metallurgical Problems 3. Exploration 4. Mining Methods 5. Mining Details 6. Filling 7. Pillar Extraction 8. Costs HISTORY Noranda is a relatively young enterprise, with much of the personal character of its founders woven into it. The name Noranda is an abbreviation of Northern Canada and the name has been a happy one for an enterprise based on northern resources, tenacity and courage. The discovery credit goes to Ed. H. Horne. This intrepid prospector returned again and again to his sulphide discoveries on the shores of Osisko lake and, in 1922, after ten years of prospecting, succeeded in interesting S. C. Thomson and H. W. Chadbourne in his discoveries. The early exploration by L. K. Fletcher, from 1922 to 1925, for Thomson and Chadbourne, indicated promising, but somewhat perplexing, ore conditions. Mr. E. Hibbert and Mr. H. L. Roscoe rook on the task of preparing the mine for production and building a smelter in 1926, and this difficult task in this isolated area made steady progress and the smelter was blown-in in December, 1927.

Jan 1, 1937

By C. R. Edwards

"Equity Silver Mines Limited, Canada's largest silver mine, has designed, built and operated a leach plant to reduce the levels of antimony and arsenic in its silver-gold-copper flotation concentrate. The orebody contained deleterious antimony and arsenic minerals in such proportions that the economic long-term sales contracts necessary to obtain project financing could not be procured. Construction of the leach plant therefore allowed development of the mine to proceed. Although the plant took some time to reach design throughput and product specifications, due to the complex and unique nature of the operation, these goals were successfully met and surpassed. This paper describes the physical plant and/or process technology modifications made to mold the main processes-concentrate leaching and filtering, autoclaving and filtration of by-products, and crystallization of salt cake-into an effective, economic operation.IntroductionEquity Silver Mines Limited, a member of the Placer Development Group, owns and operates an open-pit silver mine and related facilities located 37 kilometres southeast of Houston in north-central British Columbia. The mine occupies a 44 I-hectare (1089 acre) site at an elevation of 1300 metres (4265 feet) on the Nechako Plateau. Producing a copper concentrate containing high values of silver and gold, it is the largest silver mine in Canada and one of the largest in the western world. Equity stresses open communications, positive motivation, and production with safety, and achieved the best mine safety record in western Canada in 1984."

Jan 1, 1985

By C. Stamberg, W. McGuire, R. C. Carlson, L. W. Vollmer

"The selection of materials and pre-cautionary measures for handling natural gas and condensate containing aqueous hydrogen sulphide are presented. Based on the results of a pilot production test and laboratory studies, together with several years . of operating experience, it was found that the behaviour of materials in sour gas environments can be predicted sufficiently accurately for engineering purposes.The selection of proper materials is essential for preventing sulphide-stress cracking. Where high strength materials are not required, low car-bon steel is used. Components requiring high tensile strength and hardness characteristics should be made from K-monel or properly heat-treated carbon-manganese-molybden-um and AISI 4140 steels. Welded connections are a potential source of sulphide-stress cracking. Consequently high quality welding and strict inspection are suggested as the most economical precautionary measures available.A maintenance program based,. where possible, on visual inspection of equipment and/or test spools located at strategic points should be used to follow weight loss and putting corrosion in sour gas environments. If severe weight loss or pitting corrosion is encountered, inhibitors have been found to be an effective deter-rent."

Jan 1, 1960