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By A. H. Anderson

THE travelling grate coking process was developed by Shawinigan Chemicals, Limited, at their Shawinigan Falls plant. The first production unit went into operation a month prior to the outbreak of the war. Since then a substantial part of the coke used in the manufacture of calcium carbide has been produced by this process. In the following will be given a short account of the development work, a description of the process and the equipment, a discussion of the properties of the coke, the economics of the process and its future possibilities. EXPERIMENTAL WORK The carbide industry is a large consumer of coke, one ton of commercial carbide requiring for its production 1,200 lb. This coke must meet certain specifications in order to be acceptable. It should have a low ash content, preferably below 8 per cent, and the sulphur and phosphorus content must not be above specified limits. The size of the coke is also important. If it is too large it has to be crushed before it can be used in the furnaces, and if it is too fine it may have to be screened and briquetted. In addition, it must be dry. Although it was generally possible to purchase coke, including petroleum coke, and coke fines, in the quantities required, it became increasingly more difficult as time went on to obtain coke of a suitable quality at an attractive price. It was therefore natural for us to look to coal carbonization as a means of basing the supply of the fundamental raw material for carbide manufacture on something more solid than the shifting conditions of the coke market.

Jan 1, 1944

By Antonio Segatori, Bjørn Holmedal, Kai Zhang, Trond Aukrust, Knut Marthinsen

"The visual appearance and mechanical properties of aluminium alloy extrusions are strongly dependent on the microstructure and texture of the extruded profiles, where the desired microstructure and texture may depend on the specific applications. In the present work, the evolution of deformation, as well as recrystallization textures during extrusion of AA6xxx aluminium alloys, have been experimentally and numerically investigated. Extrusion trials were performed in a laboratory extrusion set-up, which enabled immediate water-quenching of the profiles at the exit of the die, and thus the possibility to capture the deformation texture prior to post-extrusion recrystallization. The textures and their through-thickness variations were experimentally measured by the electron back-scatter diffraction technique (EBSD, and the deformation textures numerically modelled by coupling FEM flow simulations and crystal plasticity (CP) simulations. Different CP models as well as different choices of model parameters were employed and evaluated for texture predictions. With an appropriate choice of crystal plasticity model and model parameters, the deformation texture can mainly be predicted, although the accurate intensities are hard to reproduce. The corresponding recrystallization textures, either generated through spontaneous recrystallization of the extruded profiles or through post-extrusion annealing, are far more challenging to reproduce with available recrystallization models.INTRODUCTION Extrusion is a widely applied thermal-mechanical process to produce aluminium profiles. The properties of the profiles, for example mechanical, fatigue, fracture, corrosion as well surface appearance, are strongly dependent on the underlying microstructure and texture, and the requirements with respect to these aspects may vary with applications (Ralston et al., 2010; Dumoulin et al., 2012; Donati et al., 2013). Moreover, it is often a challenge to produce extrusions with a consistent and homogenous grain structure and texture along as well as through the cross section of the profiles. It is thus vital to understand and be able to predict (model) how different microstructures and textures are formed and how they evolve during and after extrusion, as basis for controlling the final appearance and properties of extruded profiles."

Jan 1, 2018

By F. Crundwell, N. Steenekamp

"The leaching of sulphide minerals generates a significant amount of energy. There are three systems that might be used to remove this energy. These are: cooling coils, quench water, and flash recycle. Flash recycle is the recycling of slurry from the autoclave to the feed tank. Heat is removed in this arrangement when the slurry at elevated temperature and pressure is flashed to atmosphere, releasing steam. The slurry is returned to the autoclave at lower temperature, resulting in cooling. The cooling is directly proportional to the steam released from the recycled slurry. Design equations and results for the flash recycle system are presented. A fourth proposal for removing heat is to recycle slurry from the back of the autoclave. These four alternatives not only remove the heat, but also have an effect on the leaching efficiency. Amongst the four alternatives, design calculations indicate that the flash recycle option is the optimal solution in terms of leaching efficiency and heat removal, and recycling product from the back of the autoclave is the worst. In spite of its efficiency in terms of heat removal and leaching, the implementation of the flash recycle system is limited to a few operations in the platinum industry.INTRODUCTIONIn considering ways to improve leaching operations, focus is placed on the chemistry, on the kinetics, the agitation and perhaps even on the gas mass transfer conditions. Attention is less frequently placed on the removal of energy from these reactors and how this might limit performance.The pressure leaching of sulphides releases a significant amount of heat. For example, the reaction for the leaching of chalcocite, Cu2S, given by"

Jan 1, 2012

By L. R. Wilkinson, W. J. Howarth, G. J. Wenk

Over a period of three years, a cooperative program in Australia has resulted in the development of radioisotope immersion probes for the on-stream analysis of mineral slurries. Two basic probe types are now available on a commercial basis - fluorescence and absorption probes - and within each type there are a number of variations so that optimum sensitivities can be obtained for elements with atomic number greater than titanium (22), thus covering most metals of interest to modern metallurgy.

Jan 1, 1973

By G. V. Fernandez

Sociedad Minera Cerro Verde S.A.A leaches secondary copper sulfides. In recent years, the mine has introduced innovations that have improved the management of mineral crushing, agglomeration, curing, and leaching. The crushing plant, for example, uses the concepts of degree of balance and percentage of time in an operationally balanced state which, displayed in real time, facilitate more intensive and uniform utilization of the crushers. High agglomerate quality is ensured with the correct dose of moisture, which is adjusted to the changing characteristics of the mineral through the use of electrical conductivity measurements. The amount of acid used for curing the agglomerate is also adjusted by using quality control information. Finally, the stockpile irrigation regime is managed using the criteria established by the "Lixiviant Request Rate", which optimizes the addition of leaching solution, creating such benefits as faster recovery, and reduced acid and energy consumption.

Jan 1, 2007

By W. S. Hegler

Introduction The San Antonio mine is on the north shore of Rice lake, thirty miles east of lake Winnipeg and 120 miles northeast of the city of Winnipeg. Since production was started in 1932, about 2,000,000 tons of ore have been mined. Currently in progress is an extensive development programme which involves 11,500 feet of crosscuts, 3,800 feet of raises, 1,753 feet of shaft sinking, and 160,000 cubic feet of slashing, all in footwall waste rock. It is the purpose of this .paper to indicate the necessity for this work and to describe the methods employed to carry it out. Where unknown factors are as prevalent as they are in the average Canadian gold mine, a definite answer cannot be given as to what is the most economical and efficient system for mining dipping deposits. At San Antonio, the host rock for the orebodies, locally termed basalt, occurs as a sill some hundreds of feet in width and dipping at approximately 45 degrees from surface to an unknown depth. It may be assumed that it continues well below the lowest depth established to date by diamond drilling. At present, a vertical winze (No. 3 winze) hoists the ore from the 2,360-foot level to the 1,600-foot level, on which it is hauled about 900 feet to No. 3 shaft, also vertical, and there hoisted to the mill bins on surface. To maintain ore reserves at a five-year figure, at full production, additional deep exploration was required immediately. It was decided to sink No. 4 winze, a vertical opening of the same size as the other operating shafts, to provide ten additional levels (17 to 26) at 150-foot intervals, with additional depth to allow for an underground crusher installation and usual loading-pocket facilities for three-ton skip-hoisting. The winze was bottomed at 1,753 feet below the collar, at a depth of 4,117 feet below surface, and is the deepest man-sized opening in Manitoba.

Jan 1, 1949

By G. Van Weert, O. Wang

"As part of a general review of processing double refractory ores through Barrick Gold’s autoclaves / CIL facility at Goldstrike, blanking the preg robbing native carbon in the process solids with hard (m.p. 55 - 60 º C) paraffin wax was studied, specifically in relation to pressure oxidation. The improvement in CIL gold extraction was found to depend on the wax addition point, with hot, dry contacting of the ore in the presence of wax - prior to POX - yielding the largest, most consistent improvement in gold extraction.INTRODUCTIONDouble refractory gold ores present two barriers to gold extraction. The first is generally a physical barrier: the gold is encapsulated or dispersed in a matrix which is impervious to the gold lixiviant. In most cases, including Carlin Trend, NV, deposits, this involves a pyrite or arsenopyrite matrix, although minor gold may also be dispersed in competent silica (quartz) or iron oxides. Gold can be rendered accessible by oxidative destruction of such sulphide matrices. At Goldstrike this is practised by roasting and autoclave oxidation (Thomas, 1994). It is the latter route to which this paper refers.The second barrier refers to the actual gold recovery. Gold may be extracted from the pressure oxidized solids with cyanide, forming a gold cyanide complex. One characteristic of this complex is that it adsorbs on graphitic surfaces. This is taken advantage of on a large scale by gold millers, who use manmade activated, i.e., graphitized carbon particles to remove the gold from solution during leaching: the Carbon-In-Leach, or CIL process. The gold cyanide bearing carbon particles are larger than the ore solids and can be separately recovered by screening. Goldstrike uses the CIL technology to recover gold. The second barrier becomes problematic when the ore naturally contains graphitic orcarbonaceous material, hereafter referred to as native carbon (versus the man-made activated carbon). This material may also adsorb gold cyanide in competition with the activated carbon. Since the native carbon is ground with the ore it is much smaller than the activated carbon. Any competition between the two carbons may produce a loss of gold from the pregnant leach liquor to the process tailings. This phenomenon is called “preg robbing”. Goldstrike ores come from the Carlin trend, which is known for the occurrence of native carbon (Adams & Burger, 1998; Schmitz, Duyvesteyn, Johnson, Enloe & McMullen, 2001; Tretbar, 2004)."

Jan 1, 2012

By A. Saigal

A finite element analysis based investigation using DEFORM software was undertaken to model the extrusion of 15% alumina and 15% silicon carbide reinforced aluminum metal matrix composites. The study dealt with predicting the extrusion load as a function of ram displacement and initial billet temperature. The finite element simulation was also used to determine the maximum extrusion load, temperature distribution, maximum temperature, strain rate, velocity and stress distributions in the billet during the hot extrusion process. The constitutive equation used was of the type: Z = E exp(Q RT) = A{sinh(ao-)}" where Z is the Zener-Hollman parameter (temperature compensated strain rate), s is the strain rate, Q is the activation energy, R is the gas constant, T is the absolute temperature, a is the flow stress and A, a and n are constants. Based on the work of Davies et al and McQueen and Konopleva, the values of Q (KJ/mol), a (MPa-1), n and A for aluminum 6061 composites reinforced with 15% alumina and 15% silicon carbide used are 181, 0.024, 4.15 and 1.33x10'2 and 233, 0.052, 2.60 and 1.26xl0'4, respectively. Even though the individual parameters are quite different, it was found that the predicted maximum extrusion load, temperature distribution, maximum temperature, strain rate, velocity and stress distributions are quite similar and differ by no more than 1-2 percent between the two composites indicating that the deformation behavior is primarily controlled by the matrix material and is not a function of the type of reinforcing ceramic particulates.

Jan 1, 2004

ABSTRACT Inco’s Iron Ore Recovery Plant was operated by Inco from 1955 to 1980 near Sudbury, Ontario. As exposures to specific nickel substances have been associated with adverse respiratory endpoints it is important to understand processes giving rise to such substances. This manuscript discusses the process and equipment, the propensity for aerosol formation, and operational procedures used by Inco in roasting a pyrrhotite concentrate, reducing the nickel in the formed oxide, leaching the nickel in ammoniacal solution, purifying the resulting solution, making green or black NiO, and producing iron oxide pellets. Industrial hygiene measurements are also reported.

Jan 1, 2013

By R. Lowery

TODAY, man uses, at will, the land, the water, and the air to transport himself and his goods everywhere across the face of the world. He no longer thinks with wonder of the magic of conquering these elements - he takes his mastery of them for granted. He is, however, constantly striving to squeeze more and more efficiency from each mode of transport. Man's first method of transporting himself and his goods was, obviously, himself; then he acquired his first beast of burden - woman. Most other two-legged female animals carried their young around clinging to their fur. Human mothers were, generally speaking, furless and their offspring less 'Prehensile, and so slings and other trappings were invented to carry young children. Man's inventive genius soon adopted these devices for carrying other burdens, and for countless centuries woman carried all in order that man could walk unencumbered except by his weapons. Later other ?beasts of burden were trained and used, including dogs, horses, oxen, camels, etc. Man also discovered quite early that he could drag along the ground more than he could carry on his back.

Jan 1, 1956

By J. O. G. Sanderson

Introduction In this paper it is proposed to review the history of petroleum geology in western Canada, to discuss some of the main events which have affected its progress, to mention its relationship to the petroleum industry, and, finally, to appraise its present status and possible future importance. It will be useful first to consider the meanings of the terms petroleum geology, petroleum geologist, and the petroleum geology of a terrain. Petroleum Geology. - In simplest terms, geology is the science of the earth. Hence petroleum geology is the science of that portion of the earth that encloses pools of petroleum. The systematic delineation and study of stratigraphic geology began about 1820. The systematic development and study of petroleum geology started about 1910. It is a relatively immature branch of geology. Petroleum Geologist. - This term may be applied to a fully qualified geologist who is engaged for a time, be it a job, a contract, or a lifetime, in the work of finding and developing deposits of petroleum and related substances. No man may properly be called a petroleum geologist who is not first a fully qualified geologist.

Jan 1, 1946

By A. J. Stapleton

"The Copper Mountain mine of Gaspe Copper Mines, Limited was brought into production in January, 1968.This paper describes the organization, scheduling and control of maintenance of large open-pit equipment, including 8-cu.yd shovels and 85-ton electric-wheel haulage units. The facilities for repair as well as maintenance are also described, including repair shops and field repair equipment. Maintenance costs are discussed and particular reference is made to tire inspection, records and costs."

Jan 1, 1969

By T. Adamcewicz

The province's lignite resources lie mainly in the south, extensions of the much larger deposits in Montana and North Dakota. Because of planned additional capacity, conventional steam power generation will probably remain as the dominant resource usage for many decades. Conversion of coal to other energy forms is receiving emphasis and in the future will compete with steam power generation in terms of quantities used.Economic deposits, minable by present-day technology, have been generally defined. Because a large percentage of the total lignite resource is in seams containing multiple partings, future extraction will become much more difficult and capital intensive.Increased public involvement will ensure that the impacts of future coal mining and usage operations are compatible with environmental and social objectives.

Jan 1, 1982

By Mark W. Booth

THE Dominion Steel and Coal Corporation, as a coal mining concern and as a steel industry, has much pumping to do, and the conditions are as varied as it is possible to make them. We are faced with handling large quantities of water at low heads, and small quantities of water at high heads. We have fresh water, we have salt water, and we have highly acidulous water (see Table II). Our pumping problems are concerned chiefly with mechanical reliability, continuous, reliable operation, first cost, and operating cost. The Corporation is actually expending more than 15 per cent of its power consumption at the mines in pumping water, and at the steel plant about 17 per cent; that is to say, 16 per cent of the Corporation's entire power consumption goes into pumping water ( see Table I). We are pumping out of the mines 2 ½ tons of water for every tan of coal that is produced. At the Steel Plant, we are pumping 188 tans of water for every ton of steel we produce. (See Tables III and IV). The mine is pumping at high heads, up to as high as 1,400 feet in one lift ; in the Steel Plant it is, fortunately, at lower heads, 250 feet or 110 lb. being the general maximum. It behooves us, therefore, to look into the question of efficiency. In whatever direction we can gain something, it will be worth while. The centrifugal pump is not an adaptable machine. That is, a pump designed for some particular location and purpose will not always work efficiently if installed in some other place and used for some other purpose. It must generally be designed for the particular job it has to do. Reciprocating pumps are not so sensitive. We have Cameron plunger pumps that can be set up almost anywhere in a mine and they will work, but for big jobs they are apt to be clumsy and the driving power becomes a factor- which is, in fact, the controlling factor in deciding the type of pump we use. One disadvantage of the a.c. induction motor, however, is that its speed cannot easily be controlled. At its rated speed and output, it is a highly efficient machine, but, with any change in these, its efficiency goes all to pieces.

Jan 1, 1944

By Jay Tuttle

THE spiral stoping method of mining was first seen by the writer at the Granby Consolidated Mining, Smelting & Power Company's Hidden Creek mine, at Anyox, British Columbia. Where the method received its name, or by whom it was named, is a question, but it was employed by the Granby Company at their Phoenix mine, in the Boundary district, B.C., as early as 1901-02 after they had tried unsuccessfully other methods at that large, law-grade property. its adoption there was suggested by two miners, John and Steve Swanson, then working at Phoenix, who had previously been employed in the hard iron-ore mines of Michigan and Wisconsin, where they had learned this system of mining. The method proved successful at Phoenix and also, later, at the Company's Hidden Creek mine at Anyox, where some 40,000,000 tons, or more, of ore was mined in this manner during a period of about thirty-five years.

Jan 1, 1939

By C. Allen, V. Hensel, J. S. Stachulak

"Vale has been actively evaluating new technologies to curtail diesel emissions. This paper discusses the selection, installation, operation, and evaluation of the MANN+HUMMEL SMF®-AR diesel particulate filter system to reduce diesel particulate matter emissions in underground mines. The system uses a sintered metal filter element, an iron fuel-borne catalyst with an onboard dosing system, an electric heater that uses onboard power, and a sensor-based control unit. More than 6,000 h of testing demonstrated that the system represents a breakthrough in the successful control of soot emission from light-duty vehicles with differing soot emission levels, exhaust temperatures, and duty cycles.RÉSUMÉ La compagnie Vale évalue activement de nouvelles technologies pour réduire les émissions de diesel. Le présent article discute du choix, de l’installation, du fonctionnement et de l’évaluation du système MANN+HUMMEL SMFMD-AR de filtrage des particules de diesel pour réduire les émissions de particules de diesel dans les mines souterraines. Le système utilise un élément filtrant en métal fritté, un catalyseur à base de fer dans le carburant avec un système de dosage intégré, un élément de chauffage électrique qui utilise l’alimentation incorporée et une unité de contrôle avec un capteur. Plus de 6 000 heures d’essais ont démontré que le système représente une avancée pour réussir à contrôler les émissions de suie des véhicules légers avec différents niveaux d’émission de suie, différentes températures d’échappement et différents cycles opératoires."

Jan 1, 2015

By Jun Xiao, Xiaodong Li, Chunming He, Daixiong Chen

"Benzohydroxamic acid with double dentate can react with copper to form cyclic hydroxyl oxime acid copper chelate, indicating a good selectivity for copper oxide minerals flotation, especially for malachite. The flotation results of the pure malachite mineral show a strong synergistic collecting effect between hydroximic acid and xanthate at a ratio of 3.5:1, achieving a malachite recovery of 95.5% when certain sodium sulphide is used as a sulphidizing agent in the optimal pH range. Thanks to the synergistic collecting effect, the flotation recovery of malachite of a real refractory ore flotation ,can reach over 92% under the optimum condition, a 12% higher than the recovery achieved with the conventional collectors. In industrial application, the flotation of the copper oxide minerals is improved , leading to a high efficiency utilization of copper oxide resources.INTRODUCTIONBeneficiation of copper oxide ore is one of the recognized challenges in mineral processing industry. Copper oxide ore is a vital component of copper resource in the world, which has abundant reserves. Majority of sulphide deposits has oxidized zone on the top, and some deposits are oxidized to become the large and medium-sized oxide deposits (Willam & Chavez, 2001). Most copper oxide ores have problems in processing such as high slime consumption, poor floatability, complex ore property and low flotation recovery, so it is of great significance in beneficiation of copper oxide ores to develop an efficient collector, especially for malachite (Fu & Gu, 1997; Wen, 2010; Riet, Kier & Elford, 1980). At present, sulphidization-xanthate flotation is the most important method for treating copper oxide ore. In recent years, due to the decreasing ore grade, the utilization of refractory copper oxide ore draws more and more attention (Zhou, 2003), except for sulphidization-xanthate method, chelating flotation method (Lu, 2009), chemical beneficiation method (Lenormed, Salman & Yoon, 1979), microwave radiation flotation method, hydrothermal sulphidization-flotation method (Mao, Wen & Fang, 2014) and ammonia leaching of sulphide precipitation-flotation method (Lekang, Stevik & Bomo, 2003) have occurred."

Jan 1, 2016

By H. G. Rushton, A. S. Romaniuk

"The opening chapter of this volume, by A. Ignatieff, places in perspective Canada's coal resource base as part of the world scene. This chapter will focus on the Canadian scene.Units of measurement in this report are in the International System of Units (SI) as approved for official use by the Canadian Standards Association and Metric Commission Canada. These units have been adopted by the Mining Association of Canada and the Coal Association of Canada. To assist with the shift to metric units these two associations have published ""Metric Practice Guide for the Canadian Mining and Metallurgical Industries"", 1978(1J, Appendix ""A"" lists some useful conversion factors along with SI prefixes. The last official assessment of Canada's coal resources and reserves was done by the Department of Energy, Mines and Resources and presented in Report ER 79-9 ""Coal Resources and Reserves of Canada"", published in December 1979 and authored by H.U. Bielenstein, L.P. Chrismas, B.A. Latour and T.E. Tibbetts(2). The Geological Survey of Canada has a continuing project concerned with coal resource assessment as does CANMET, whose concern is with coal reserve assessment and coal quality. As well, Alberta's Energy Resources Conservation Board (ERCB) has a continuing assessment program for coal in Alberta and publishes an annual reserves report, the current issue of which is cited as reference No. (3). The difference in resource and reserve terminology as used by EMR and ERCB has a major effect on derived tonnages for Alberta. This difference will be discussed later. In 1982 the Department of Energy, Mines and Resources produced a map titled ""Canada-Coal""<4J which outlines coalfields and illustrates coal import and export movements for the years 1981and1980. A copy of this map is contained in the map pocket of this publication. Two other resource assessment reports are noteworthy, the first is ""Coal Resources of Southern Saskatchewan: A Model for Evaluation Methodology"", by J.A. Irvine, S.H. Whitaker and P.L. Broughton<SJ which is one of the major outputs of a joint federal-government study of southern Saskatchewan's lignite deposits. (Another output from this same study' is the Geological Survey of Canada's SASCO file, a computer processable file holding borehole and coal quality data.) The second is ""Deep Coal Resources of the Interior Plains, Estimated from Petroleum Borehole Data"", by G.D. Williams and M.C. Murphy(6) which identifies coal resources from nearly 4,000 petroleum exploration boreholes distributed uniformly over an area spanning Manitoba, Saskatchewan, Alberta and British Columbia."

Jan 1, 1985

By David Humphreys

It is difficult to overstate the importance of China to the future of the world mining and metals industries. In a remarkably short time, China has risen to become the world?s largest producer and consumer of steel and its second largest consumer of non-ferrous metals such as copper and aluminium. It is currently the world?s largest buyer of copper on international markets, the second largest buyer of iron ore, and the third largest buyer of alumina. At the same time, it is the world?s largest or second largest producer and exporter of tin, lead, zinc, magnesium and a host of minor metals and industrial minerals, as well as a fast-growing exporter of coal.

May 1, 2002

By L. Li, K. Jiang

China is the world largest producer and consumer of zinc. Beijing General Research Institute of Mining and Metallurgy (BGRIMM) is one of major research and engineering institutes for nonferrous metallurgy in China. This paper (presentation) introduces the development of China’s zinc smelting industry, key production processes and main producers. The process research and development are reviewed as well as BGRIMM’s R&D activities in the last decade. China&apos;s refined zinc production was 4,829kt in 2012, accounting for 38.6% of world production. Primary production was 4,722kt. There are around 150 refined zinc producers in China. The traditional fluid bed roasting - leaching jarosite is still a dominant process for primary production and its production accounts for about 60% of country&apos;s total production. However, the direct leaching process is gaining market share. Seven direct leaching plants with 330kt/a capacity, including autoclave leaching and the Outotec direct leaching, have been put into production by June 2013. Five autoclave leaching projects with 590kt/a capacity are in the pipe line and are expected to be commissioned in 2014 and 2015. To cut the production cost and improve smelter economics, process research to optimize the production flow sheet, to improve the iron removal and to enhance the recovery of co-existed rare metals were carried out. The development trends of China’s zinc smelting industry from the view of cutting production cost, improving energy efficiency, increasing comprehensive utilization are discussed accordingly.

Jan 1, 2014