Search Documents

By Victor Dolmage

Introduction Although gold production in British Columbia began in 1859, lode gold was not produced till 1893. Since 1900, the annual production of lode gold has fluctuated between $3,000,000 and $6,000,000. About twenty per cent of this production may be regarded as by-product gold from base metal mining. The remainder comes from a few isolated but important mines, such as the Rossland mines, Nickel Plate, Surf Inlet, Premier, Pioneer, Bralorne, Reno, and Cariboo Gold Quartz, and from several less important mines. All of the above, except Pioneer, Bralorne, Reno, and Cariboo, are approaching or have reached the point of exhaustion, but all are now receiving, under the stimulus of the. present gold-mining boom, drastic resuscitative treatment, with, in some cases, signs of resurrection. Notwithstanding this, however, the main interest at the present time is focussed on the Bridge River and Cariboo fields. Both these fields were discovered in the early 'sixties' and, apart from the Cariboo placer production, both have from time to time contributed small amounts of lode gold; but it is only during the last two years that the real possibilities of these areas were discovered. and that they began to assume the appearance of goldfields of major importance. The two fields are sorme three hundred miles distant from one another and contain deposits of distinctly different types, so that the only reason for including them in one article is the fact that they came into prominence more or less simultaneously and at a time coinciding with, but not otherwise related to, the present gold-mining boom.

Jan 1, 1934

By M. T. Ho, D. E. Wiley

The iron and steel industry accounts for almost 5 % of the total world CO2 emissions. Optimisation of the steelmaking process has led to significant reductions in the energy intensity to the point where it is now close to the thermodynamic limit. Further reductions are not likely to be achieved with efficiency improvement alone and will require the development of novel or breakthrough technologies. This paper will show the costs of implementing CO2 capture at direct atmospheric emission points for a number of iron and steel production processes. These include a conventional process, top gas recycling processes, the Corex and Hismelt smelt reduction processes and the Midrex direct reduction process. Depending on the point source emission, costs of capture with existing chemical absorption technology at iron and steel plants can be similar to capturing CO2 at pulverised coal fired power plants.

Jan 1, 2015

By P. Groleau, O. Tavchandjian, D. Marcotte

In open pit mining, each small mining unit (SMU) is selected for mill processing based on an estimate of its true grade. The estimation is usually done using analyses of cuttings from blast holes within that SMU. One common estimator used for selection is the arithmetic average of within-SMU samples. This estimator is conditionally biased. The effect of a conditional bias is to overestimate the profit really recovered from the deposit. For this reason, a conditionally unbiased estimator is preferable. Increasing the number of samples generally improves the accuracy of the estimation (and diminishes the conditional bias, if present, of most estimators). However, there exists a practical limit where an additional sample does not improve the estimation sufficiently to cover the expense of making the analysis. This limit is specific to each deposit and depends on geostatistical parameters, economic factors, and mining parameters. This study examines how the number of samples affects the recovered reserves and the resulting profit. Also, the effects on optimal profit of varying the different factors are examined. Globally, the number of samples required increases with the selectivity of the operation. For a given ore deposit, the greater the number of SMUs selected for processing, the fewer samples are required and vice-versa.

Jan 1, 1998

By G. A. Sutton

"At the San Manuel mine (Arizona, USA), in-situ copper leaching of a copper porphyry deposit was carried out from 1986 to 1999 during underground and open-pit mining. In 1993–1994, well¬field testing of the supergene zone, composed primarily of chrysocolla and copper-rich clay minerals, led to estimates that 52% of the acid-soluble copper (ASCu) could be recovered during in-situ leaching; however, the actual recovery from zone 6, which had the longest leach history, was approximately 42%. Comparing drillcore assay data from holes drilled before and after leaching also indicated an approximate recovery of 42%. The discrepancy between the predicted (52%) and actual (42%) recovery is probably related to several factors, including difficulty maintaining fluid saturation, channelling effects, and gypsum precipitation. ¦ KEYWORDS Copper oxides, in-situ leaching, Modelling, Porphyry, Solvent extraction and electrowinning (SXEW), Well-to-well RÉSUMÉ À la mine San Manuel (Arizona, États-Unis), on a procédé de 1986 à 1999 à la lixiviation in-situ de cuivre d’un gisement porphyre cuprifère pendant l’exploitation minière souterraine et à ciel ouvert. En 1993 et 1994, des essais effectués dans des champs de captage de la zone supergène, composée principalement de chrysocolle et de minéraux argileux cuprifères, ont abouti à des estimations selon lesquelles on peut récupérer 52 % de cuivre soluble dans l’acide (ASCu) pendant la lixiviation in-situ ; toutefois, la récupération réelle dans la zone 6, qui affiche l’histoire la plus ancienne en matière de lixiviation, était d’environ 42 %. La comparaison des données d’analyses de forage obtenues à partir de trous forés avant et après la lixiviation indiquait également une récupération approximative de 42 %. La différence entre la récupération prévue (52 %) et réelle (42 %) réside probablement dans plusieurs facteurs, notamment la difficulté à maintenir la saturation des fluides, les effets de canalisation et la précipitation du gypse. ¦ MOTS CLÉS d’un puits à l’autre, extraction par solvant et extraction électrolytique (SXEW), lixiviation in-situ, modélisation, oxydes de cuivre, porphyreINTRODUCTION in-situ copper leaching at the San Manuel mine, Arizona, USA (Figure 1), began in 1986. It was recognized that some of the copper oxide resource was not economically recoverable by conventional open-pit and heap leach methods using solvent extraction and electrowinning (SXEW) and a high stripping ratio would be required to access part of the resource. At the time, in-situ leaching was becoming popular in the uranium industry, but the approach was virtually unknown in the copper industry, especially at a large scale."

Jan 1, 2019

By Henri-Loui Jacob, Suzie Nantel

"Depuis la fin des annees 1800, la province de Grenville represente pour Ie Quebec une source importante et diversifiée de minéraux industriels. Le Ministère de l'Énergie et des Ressources du Québec, dans Ie cadre de I'entente auxiliaire Canada-Québec, et les compagnies minieres y ant multiplié, surtout depuis 1983, leurs travaux d 'exploration, de cartographie, et d'évaluation pour les minéraux industriels. Ces travaux ant conduit ala découverte et ala mise en valeur de gisements de granite architectural, de graphite, de dolomite et ant aussi permis de repertorier des gîtes et des indices prometteurs de wollastonite, de silice, de calcite. de dolomite, de silicates d'alumine et de terres rares. Les gisements récemment découverts sont actuellement exploités au sur Ie point de l'être et les gîtes et les indices les plus prometteurs ant été jalonnés.ABSTRACTSince the late 18oos, the Grenville Province in Québec has been an important and diversified source of industrial minerals. The Ministere de l'Énergie et des Ressources du Québec, under the Canada-Quebec Mineral Development Agreement, and the private sector have put an emphasis on exploration, mapping and evaluation programs in the Grenville Province for minerals, particularly since 1983. These programs have led to the discovery and the development of deposits such as architectural granite, graphite and dolomite, and have also led to inventories of occurrences and prospects of wollastonite, silica, calcite, dolomite, alumina silicates and rare earths. The deposits discovered lately are presently being quarried or will be in the near future. The most promising occurrences and prospects have been claimed."

Jan 1, 1990

By B. K. Choi, G. E. Kim, S. Noh, T. K. Kim

Oxide dispersion strengthened (ODS) steel has been developed as the most prospective core structural material for next-generation nuclear systems because of its excellent high strength and irradiation resistance. In ODS steel, finely dispersed nano-oxide particles with a high number density in the homogeneous grains can be very attractive to achieve superior mechanical properties at high temperatures, and these favorable microstructures can be significantly changed using process parameters during the mechanical alloying procedures. In this study, the effects of mechanical alloying times on the microstructure of 10Cr-1Mo ODS martensitic steel were investigated. Pre-alloyed powders with Y2O3 powder were mechanically alloyed for various milling times using a high energy horizontal ball-mill apparatus (model: symoloyer CM20). Powder properties such as the mean particle size, size distribution, and crystallite size were evaluated. Uniaxial hot pressing was employed to consolidate the milled powders. The results of a microstructural observation after the MA and UHP processes indicated that the homogeneity of the martensitic structures was considerably increased with the longer milling time. It is thus concluded that the mechanical properties of the ODS martensitic steel are greatly dependent on the mechanical alloying times.

Jan 1, 2015

By Greg Gosson, Larry B. Smith

"These are heady times for the mining industry, with strong metal prices, investor enthusiasm for the junior explorer and ready access to finance for mineral projects. Many projects were shelved in the past because of technical deficiencies — insufficient tonnes or grade, metallurgical problems, the deposit was too deep or too narrow, or the project was physically or economically under water. With the possibility of sustained metal prices, now is the time for those previously “challenged” projects to be re-evaluated and financing sought for continued development. The question is, do these deposits have reasonable prospects for economic extraction, as required by all mineral resource reporting codes? NI 43-101 defines a mineral resource as that portion of the mineral inventory that has reasonable prospects for economic extraction. However, a mineral resource is not simply an inventory of all blocks above a given cut-off grade. The spatial distribution and geological and grade continuity must also be considered. The qualified person (QP) must consider factors significant to project economics at the mineral resource estimation stage, and not just when qualifying mineral reserves. CIM Best Practice Guidelines for estimating mineral resources require the factors significant to project economics be current, reasonably developed and based on generally accepted industry practice and experience. In establishing the cut-off grade, it must realistically reflect the location, deposit scale, continuity, assumed mining method, metallurgical processes, costs and reasonable long-term metal prices appropriate for the deposit. Variations within the resource model (rock characteristics, metallurgy, mining methods, etc.) may necessitate more than one cut-off grade or economic limit in different parts of the deposit model. There must be sufficient knowledge of the metallurgical characteristics of the deposit, which should be supported by preliminary metallurgical test results."

Jan 1, 2003

By M. L. Joy

The heat pipe is a self-contained, passive structure that uses a liquid-vapour fluid cycle to provide high thermal conductance . Through the proper selection of working fluids and container materials, heat pipes have been operated at temperatures ranging from less than -300°F to more than 3,000 °F. The passive nature, high efficiency and configuration flexibility of the heat pipe are presented. The application of McDonnell Douglas Astronautics Company Cryo-Anchor® heat pipes for foundation and support stabilization in permafrost regions is discussed. Using the proven Cryo-Anchor technology base. a proposed application of heat pipes in a cold -region mine ventilation system heat recovery heat exchanger is presented. Information obtained from the development of an air-cooled heat pipe steam condenser provides the technical basis for large -scale heat pipe applications.

Jan 1, 1978

By S. G. Enns, E. W. Yarrow

"Situated about 200 km southeast of Juneau, Alaska, within the lower Stikine River region of northwestern British Columbia, the Galore Creek porphyry Cu-Au deposits are hosted by Upper Triassic to Lower Jurassic alkaline volcanic rocks and comagmatic syenite intrusions. Early and late breccias are also locally important host rocks for mineralization. Of the twelve identified Cu-Au deposits, the most important are the Central zone, Southwest zone and the Junction deposits with a combined resource of 284 million tonnes at 0.67 % Cu.The composition of the intrusive rocks is predominantly silica-undersaturated, alkaline, and metaluminous. Four intrusive suites are identified from field, petrographic and petrochemical data. Variation within suites or lineages can be explained by alkali feldspar fractionation. An oscillation between porphyritic and equigranular intrusions is suggested by the sequence of different intrusive lineages. The youngest intrusive phase is silica-saturated.A complex succession of intrusive and hydrothermal events is demonstrated at Galore Creek, with the most intense alteration and mineralization developing early in its history. In the Central zone, early Ca-K-silicate alteration, dominated by garnet, biotite, Kfeldspar, and anhydrite grades outward into K-silicate alteration. Both are locally overprinted by retrograde sericite± anhydrite± carbonate (SAC) alteration. The most intense Ca-K-si/icate alteration, a magmatic-hydrothermal breccia, and an early syenite intrusion are all coincident with copper mineralization in the core region of the Central zone. However, higher grade mineralization in the zone, exceeding 1 % Cu with more than 0.5 g/ t Au, is typically associated with intense biotite-rich, K-silicate alteration primarily hosted by altered volcanic rocks. The highest gold grades, commonly exceeding 1 g/t, are associated with bornite-rich mineralization situated in the northern and southern parts of the Central zone.Mineralization in the Southwest zone occurs as disseminated chalcopyrite within a late, diatreme breccia and adjacent K-feldspar porphyry. In the other satellite deposits, disseminated chalcopyrite and bornite occur in volcanic rocks with alteration that is similar to the Central zone."

Jan 1, 1995

By P. A. Tichauer

Arbitration is a flexible method for dispute resolution that gives control to the disputing parties while still maintaining a clear and well-structured decision making process. It responds to the desires of the parties for a resolution that is fair, binding and enforceable and is guided more by pragmatism, efficiency, effectiveness and equality than by a need to comply with the legal procedures and practices of any single country or jurisdiction. Arbitration is particularly well suited for the resolution of disputes pertaining to international commercial agreements which are often present in the metallurgical sector. This paper provides a simplified outline of the features and advantages of arbitration as well as commentary regarding certain prerequisites in order for arbitration to be binding and enforceable.

Jan 1, 2015

By John C. Luck Jr.

"DEVELOPMENT of oil emulsion mud dates back to the early days of rotary drilling when oil was added to the drilling mud solely for the purpose of freeing stuck drill pipe. After the drill pipe was freed, and drilling resumed, this oil was considered a contaminant. Efforts were made to remove the oil but some of it remained and was emulsified with the drilling mud, thus forming a mechanical emulsion.During the late 1930's, operators found that adding crude oil to drilling muds seemed to alleviate 'sticky-hole' problems and so oil was allowed to remain in the mud. This practice was adopted when it was found that faster drilling rates and longer bit life were obtained. These observations led to the development of emulsion drilling muds. During the past five years their application has become more widespread because of the lower fluid losses obtained, greater lubrication qualities, faster penetration rates, and generally better hole conditions.An emulsion may be defined as a two-phase system consisting of a mixture of either finely divided oil droplets in water or of finely divided water droplets in oil. The surrounding liquid is known as the continuous phase. The emulsifiers reduce the interfacial tension, making the droplets tend to repel each other so that they remain dispersed and stabilized. These emulsions are classified as oil-in-water or as water-in-oil, depending upon whether water or oil, respectively, is the continuous phase. Briefly, close inspection shows that they consist essentially of globules of• the one liquid suspended in a continuous mass of the other liquid. Oil emulsion muds are usually of the oil-in-water type. Two basic types of emulsifiers •commonly used in Canadian muds are soaps and lignites."

Jan 1, 1954

By F. W. Gray

Summarized Foreword This paper is one of a series arranged by Institute Divisional Committees for the Fiftieth Anniversary Meeting, reviewing the experience of the major mining and metallurgical industries during the life of the Institute. The viewpoint is national and broadly technical. Geology is stressed on a continental scale without regard for provincial boundaries. The boundary between Canada and the United States is, however, so decisive a factor in our coal-mining economics and our political evolution that mention of its implications cannot be avoided. The Laurentian Shield in Canada makes the occurrence of coal deposits a geological impossibility between the St. Lawrence Lowlands and the Great Plains. All but five per cent of Canadian coal resources occur west of Winnipeg. The utilization of this ninety-five per cent of our coal wealth has to date been a consequence of transcontinental railways' development, and the small fuel needs of thinly populated wheat farming and cattle-raising territory, in what- to judge from the development of mixed farming and greater population density of Manitoba- is merely an initial stage of agricultural intensification and accordant population growth. There is no useful purpose in measuring coal resource against consumption rate in the West as a whole, because the resource is but partially known, and it is difficult to believe that industrialism based upon coal utilization is in any but its infant stage of growth. Canada west of Winnipeg possesses, moreover resources of petroleum and natural gas, which, together with the power-potential in the long watershed of the eastern slope of the Rocky mountains, give to population centres such as Calgary and Edmonton a choice of energy resources that is almost an embarrass des riches.

Jan 1, 1948

By Hiwa Salimi, Foley. Stephen R, Loghman Moradi

Common water-miscible organic solvents including DMSO, DMF, methanol, ethanol, acetone and THF in combination with HCl and low concentrations of H2O2 were investigated for dissolution of gold. THF showed the best result demonstrating that gold powder could be completely dissolved in 1.5 hours in 1.0 mol/L HCl and 0.2 mol/L H2O2. No complete gold dissolution was observed for the rest of solvents even after 24 hours. The rate of gold dissolution was measured by dissolving gold wire in THF/HCl/H2O2 mixture. The rate of gold dissolution in optimised condition was 75 g m-2 h-1 at room temperature and significantly increased to 590 g m-2 h-1 by raising the temperature up to 60 oC. Although a THF/HCl/H2O2 mixture showed a slower dissolution rate in comparison with aqua regia, however the applied conditions are considerably milder which is highly promising for gold leaching in an industrial scale.

Jan 1, 2015

By Technische Universität Braunschweig, K. Saksl, J. Furste, P. Eschenbacher, F. Brunke, D. Wolter, M. Kohnke, C. Siemers, J. Kiese, M. Schlemminger

"In general, titanium alloys combine outstanding mechanical properties with corrosion resistance and biocompatibility and are, therefore, used in many challenging applications. Nevertheless, for special products, well-tailored properties are required which might not be achievable by a specific design so that new or modified alloys are needed. In this overview paper, alloy development strategies performed at the Institute for Materials of the Technische Universitat Braunschweig are discussed at different examples, namely, (1) oxidation-resistant, microstructural-stabilized and cold-workable alloys for exhaust applications, (2) aluminum- and vanadium-free, medium-strength and cold-workable alloys for implants and osteosynthesis applications and (3) free-machining alloys by the addition of particles with low melting points for non-safety critical light-weight constructions to replace heavier steels, e.g. in automotive applications. A special focus is set on the alloy development techniques and the analyses carried out to achieve well-balanced properties by the optimization of the alloy compositions. INTRODUCTIONTitanium belongs to the allotropic metals and can therefore exist in two different equilibrium lattice modifications. Pure titanium crystallizes at 1668°C in a body centered cubic (bcc) structure called ?- titanium which at 882°C transforms to a hexagonal close packed structure (hcp), the a-titanium. A martensitic ?-to-a-transformation is possible at large cooling rates. This thermally induced hexagonal martensite is called the a'-phase. The transformation temperature named ?-transus-temperature (T ?) can be influenced by alloying elements (Peters & Leyens, 2002).For titanium alloy production typical alloying elements are aluminum (Al) and oxygen (O), both a-stabilizers shifting the ?-transus temperature to higher temperatures, whereas tin (Sn) and zirconium (Zr) only show a limited influence on the ?-transus temperature. The ?-stabilizing elements are subdivided into two groups: Niobium (Nb), molybdenum (Mo) and vanadium (V) stabilize the ?-phase between the melting point and room temperature and are therefore called isomorphous -stabilizers. Elements like copper (Cu), iron (Fe) or silicon (Si) also stabilize the ?-phase to lower temperatures but undergo a eutectoid reaction during cooling. ?-titanium then dissociates to a-titanium and an intermetallic compound. Consequently, these elements are called eutectoid ?-stabilizers (Boyer, Welsh & Collings, 1994)."

Jan 1, 2016

By Damien Gaboury

"Two practical methods for correlating two or more diamond-drill core intersections, using a stereographic projection software are presented. The first may be used to establish if two or more vein intersections are correlative, based on their core angles and diamond-drillhole attitudes. The second method allows prediction of main vein attitudes from numerous intersections, based on a spherical density contouring projection. The methods are suitable for: (1) correlating veins in complex orebodies; (2) ascertaining lateral continuity of ore for reserve estimations; (3) demonstrating the hidden complexity of an orebody; and (4) correlating and interpreting various planar elements.IntroductionModern mineral exploration relies on diamond- drill core data and on the ability of geologists to interpret them. Drill core generally yields unoriented information, unless an expensive orientation device is used. As a consequence, strike and dip of planar elements such as lithological contacts or mineralized veins cannot be determined easily. This is particularly true for blind deposits (covered by thick overburden) and complex orebodies, where field data cannot support drilling interpretations. Such a problem has been addressed previously using two and three diamond drillholes and several solutions were proposed based on trigonometry, and geometric and stereographic projections (Mead, 1921; Wisser, 1932; Fischer, 1941; Stein, 1941; Bucher, 1943; Gilluly, 1944; Addie, 1962; Mills, 1963; Lyons, 1964). However, these solutions are time consuming and not relevant to present day computerized data plots."

Jan 1, 1997

By L. C. DeCory

"Concrete is a common denominator to the building process and portland cement is an integral and necessary component of concrete. The cost of portland cement is nominal and its cost comprises, in most instances, a small portion of the total cost of ""put-in-place"" concrete.The domestic demand for portland cement in Canada is projected to be slightly less than 11 million short tons in 1980. In order to achieve this projected goal, stabilization or lowering of the cost of put-in-place construction is necessary. This enhancement of the cost of building can be achieved by:(1) improving the building process;(2) refining and improving design techniques; and(3) developing improved and economical concrete products.Some of the techniques and materials that will lead to building cost stabilization include systems building in its broadest sense, slipforming, precasting, prestressing, computer design, lightweight aggregates, fibrous concrete and integration of building components."

Jan 1, 1973

By The Staff

Introduction It is the purpose of this paper to discuss a number of the metallurgical improvements in the technology of copper-nickel ore treatment which have been introduced during recent years in the plants of ?the International Nickel Company of Canada, Limited. In common with other ore treatment processes, the procedure for extracting nickel and copper is changing almost continuous! y. These changes are necessitated by reason of changes in ore grades and characteristics, rising material and labour charges, and the constant drive to maximize metal recovery and to minimize production costs. It is not possible to present a comprehensive list of all the changes made, and only a selected number of the improvements in the milling, smelting, and refining operations are covered. It should be clearly understood that some phases of the procedures described have been pioneered by others in kindred fields and due acknowledgment is given to their foresight and efforts. Articles have been published over the years describing the operations of the International Nickel Company plants and the reader is referred to the Engineering and Mining Journal, Vol. 130, No. 9, November 10th, 1930, and to the Canadian Mining Journal, Vol. 58, No. 11, November, 1937, and Vol. 67, No. 5, May, 1946. Other references are the Transactions of this Institute, 1932, 1938, and 1946; Metals Technology, American Institute of Mining and Metallurgical Engineers, February, 1938, and Canadian Chemistry and Process Industries, April, 1940.

Jan 1, 1948

By John Postle, Maureen Jensen, Marcel Vallee, Bernie Haystead, Dan Hora, Graham Clow

The Committee's proposed standards establish definitions and guidelines for the reporting of Exploration Information, Mineral Resources and Mineral Reserves in Canada and are identified as the "CIM Standards" and referred to as such hereafter in this document. To provide additional clarification to Qualified Persons (QPs), guidelines have been included with the respective definitions. The CIM Standards are applicable to all minerals including industrial minerals, diamonds and other gemstones. Reserve definitions for bitumen, natural gas and oil are not included in these Standards. The CIM Standards are not intended to cover mineral inventory estimates that will be reported to government agencies.

Jan 1, 2001

By D. A. Pirttinen

The promotion of improved coal quality for thermal generation can benefit our national economy. The construction of electric generating facilities in Canada is expanding at a rapid rate to satisfy the demands of a rising population and new uses for electrical energy. With remaining economic water power resources in the process of development, generation from thermal sources continues to grow. The increase in thermal capability has been somewhat arrested by a de-pressed economy, widening of inter-provincial and state transmission networks and decisions to exploit certain water resources before high capital investment is further in-creased by rising construction costs. The introduction of extra high volt-age transmission lines will further delay thermal generation planning, but in due course, when the effects of restrictive factors have been dissipated, steam-electric generation from fossil fuels will rise to considerable proportions. In time, nuclear sources will contribute a growing share to thermal power, but, it is doubtful if nuclear participation will ever displace conventional fuels for steam rising, unless it can be adapted to operate efficiently for variable outputs in peaking service. It appears certain that fossil fueled

Jan 1, 1961

By G. W. Govier

The origin and limitations of the conventional and empirical equation for the interpretation of the results of back pressure tests on gas wells are discussed. Difficulties in data interpretation arise from many causes, including Jack of flow stabilization, uncertainties in connection with the friction calculation, and the effect of turbulence near the sand face in the reservoir. A procedure is developed to ac-count for the turbulence effect. This is based upon the theoretical equation for laminar steady state flow and current knowledge of turbulent steady state flow. The procedure involves the expression of the equation for combined laminar-turbulent steady state flow in terms of a turbulence contribution factor. This factor. is shown to be dependent mainly upon the flow rate per unit of pay thickness and the reservoir permeability. The method of interpretation permits the use of judgment based upon the theory and present day under-standing of laminar-turbulent flow and is considered an improved method

Jan 1, 1961