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By P. R. Day, W. K. Webster

"The introduction of large boreholes underground initially involved taking the techniques of open-pit bench blasting to the production stope, but with deeper boreholes and narrower stopes more controlled techniques must be developed in order to maintain good stope walls and prevent dilution of ore or structural damage to pillars due to blasting overbreak. The points discussed are drilling accuracy and drill pattern, the relationship between open-pit wall control and underground mining, the varied explosives products and initiation devices available, and some of the many ways that variations in loading, such as deck charging, etc., can produce desirable results.IntroductionThe use of large-diameter blastholes for underground mining began ten years ago and today they are widely employed in a variety of orebodies and stope configurations. These big blastholes, which range in size from 4.5 to 8 inches in diameter, were originally employed in the same manner ' as open-pit bench blasts; that is, the stope was silled out to full width and all holes were drilled vertical and parallel. This was suitable for competent, massive orebodies, however the popularity of the big drills saw their usage in more narrow stopes, often with poor ground conditions. The dipping orebodies and small drill sublevels resulted in inclined drilling.Today, there is full-ring drilling of 4.5-inch holes. Some 6.5-inch holes are drilled up to 350 feet deep. A 350-foot borehole may contain 6000 to 7000 pounds of explosive. The detonation of this size of charge weight within the confines of an underground stope can have considerable effect on the stability of stope walls and adjacent pillars. Obviously, precautions must be taken to minimize the damage which would result from the large charge weights possible with these big boreholes."

Jan 1, 1982

By Karl J. C. Harries

"10.1. INTRODUCTIONDefinitions are a necessary part of every agreement. Their purposes are to assist the reader in reading and understanding an agreement and to attempt to avert potential confusion and, therefore, disputes. In some circumstances, they may be critical in deciding a dispute. As they are often substantive, they should not be treated lightly.It is far easier and less confusing for a reader to read “the Company” or “the Recipient” than to be faced with “the party of the First Part”, or to see the “Jones Property” than “that part of the property hereinbefore described in paragraph 1.01 hereof”. It is also advisable not to use “-ee” and “- or”, as in payee and payor.One thing must always be remembered: once a word has been defined in an agreement, it will always have the defined meaning unless the contrary is clearly indicated or is required to make sense of a provision.2 It can be confusing for a reader if commonly used words are defined in other than ordinary terms. Unique words that will stand out in the text are more likely to be recognized as having special meaning. It is also good practice to identify defined terms by capitalizing them in the text of the agreement. Boldfacing of definitions is also sometimes used for this purpose but, as boldfacing is not easily identified in handwritten revisions, it can be missed in the press of negotiations, especially when several typists are involved. Lack of consistency in identifying defined terms is not a fatal mistake, but it can create confusion, especially if the reader is new to the agreement or is reading it in a highly technical manner, such as when there is a dispute.If definitions used in the main text also apply to a schedule, they need not be included in both. Omitting them from the schedule makes the agreement look shorter, which to some people is a benefit. If definitions are not repeated, make certain that the schedule clearly indicates that words defined in the main text have the same defined meanings in the schedule3 and are clearly identified as defined words. In considering whether or not to repeat in a royalty schedule definitions appearing in the agreement proper, think of definitions as an aid and a reminder to the reader. Repeating them will help a reader, if only by saving the nuisance of remembering where to find them in the main text and constantly turning to it. All the definitions needed to read the schedule will be right there, so that the schedule is a self-contained document. Just make certain that, if you do repeat a definition, you repeat it in identical terms. If you have to change any defined term to make it fit the royalty provisions, use a different word or phrase as the defined term to warn the reader that he is dealing with a different concept.4"

Jan 1, 2003

By K. Adham, C. Lee

Over the last forty years, a number of specific fluidized bed applications in nickel extraction have been developed for commercial use. Five important processes have gained particular acceptance, namely, sulphide ore roasting, nickel sulphide (matte) roasting, nickel oxide reduction, laterite ore pre-reduction, and nickel chloride pyrohydrolysis. These applications involve different feed materials and process conditions, however, all benefit from fast reaction kinetics and high heat and mass transfer rates in the fluidized bed reactors. They have been studied, tested, and implemented by various nickel producers, who have published their results in many papers and patents. This paper examines the design issues surrounding the application of fluidized bed technology to the above nickel processes. Based on the available data in the open literature, computerized process modelling is used to provide generic flowsheets that illustrate the key features of each process.

Jan 1, 2004

By Ralph D. Parker

THE subject matter of this paper will be primarily restricted to the metallic mineral industry, which last year was responsible for almost 60 per •Cent of the total value of Canada's mineral production. It has been written that, in the broad sweep of eternal time, sixty years is as transient as a flicker of lightning in a summer night's sky. In the history of mankind and human endeavour, however, six decades can encompass momentous events and far-reaching •circumstances, all of which affect the lives of men and change the destiny of nations. This observation is con-firmed very positively by a study of our Canadian mining history, from either the broad viewpoint of human progress or the more specialized viewpoint of national economy. The past sixty years have witnessed vast changes in the economic importance of mining in this country's affairs, and also in the technology of the industry. Mining has emerged from the days of rule-of-thumb practice and is now taking on the stature of a highly diversified science.

Jan 1, 1962

By W. L. Ott, J. E. Hawley, C. L. Lewis

"IntroductionTHE APPLICATION of spectrochemical analysis to metals of the platinum group was advocated by Harvey (3) as follows: ""The spectra of the platinum group metals have been studied less than many of the more common metals. The rarity of occurrence of these elements makes the analysis relatively unusual. Potentially, the analysis of this group is an excellent application of spectrographic methods, particularly in contrast to the tedious chemical procedure"".Wichers (8) divides platinum-metal analysis into three broad divisions as follows :( 1) The detection and estimation of these metals in other materials, e.g., ores, where the amounts present are very small.(2) The detection and estimation of impurities in the refined metals themselves ....(3) The analysis of alloys of the platinum metals .....The present paper deals with the second division: analysis of refined rhodium.Research on spectrochemical techniques for determination of trace contaminants in refined platinum metals was begun at Queen's University in 1949, under the supervision of Professor J. E. Hawley. Since 1953, the work has been continued in the Metallurgical Laboratories of Falconbridge Nickel Mines, Limited. Techniques for spectrochemical analysis of refined platinum and palladium have been published ( 4, 5). A technique for analysis of refined iridium has been developed but not yet published."

Jan 1, 1955

By J. T. Chen, S. Winkler, M. J. Worswick, O. Orlov

This paper presents a review of research conducted at the University of Waterloo concerned with the application of aluminum alloy sheet and tube in automotive structures and body panels. The research has focussed on formability prediction and results using a range of damage-based formulations. These models include continuum-level damage approaches and, more recently, a so-called percolation damage approach intended to capture microstructural heterogeneity effects on damage development. This paper presents applications of these damage approaches to simulate formability of experiments considering stretch flange panels. The experiments consider drawbead effects associated with the bend/unbend deformation as the material flows through the drawbead. Recent work on simulating in situ X-ray tomography experiments that capture damage evolution during tensile deformation will also be reviewed.

Jan 1, 2006

By Jean-Sébastien Kroll-Rabotin, Éric Climent, Florent Bourgeois

"Falcon concentrators are enhanced gravity separators designed for concentrating fine and ultrafine slurries. The Falcon UF model is unique in that it is dedicated to beneficiation of ultrafines, one key feature being that it does not make use of any fluidisation water. In a former study, we investigated the physical mechanisms that govern the transport of ultrafine particles (in the range 10 to 80 µm) inside Falcon UF concentrators, and concluded that separation efficiency is governed by differential settling. Initially, we derived and published a predictive model of the partition function under dilute conditions. The present paper proposes an extension of the initial model to concentrated ultrafine suspensions for application to industrial scenarios. The paper discusses how hindered settling has been added into the initial model to account for solid concentration effects. The modified model is tested against experiments carried out with a laboratory scale UF Falcon concentrator from dilute conditions up to 30 vol%. A good agreement between measurements and model predictions is obtained, which confirms that our hypotheses about the physics of separation inside a UF Falcon separator remain valid even at high concentrations.INTRODUCTIONThe Falcon concentrator is a fast spinning bowl that is fed at its centre of rotation. It uses centrifugal force to separate particles that are transported inside a thin liquid film that flows upward along the inclined wall of the bowl (McAlister and Armstrong, 1998). Due to differential settling, dense and coarse particles are concentrated inside the bowl whereas light and fine particles are rejected with the overflow stream. The fast rotation speed of the bowl yields high centrifugal force several hundred times the attraction of Earth. Despite the thinness of the liquid film (between 100 µm and 1 mm with a Falcon L40) where separation takes place, the Falcon concentrator can treat high flowrates (up to 30 L/min). At the bottom of the bowl, an impeller transmits the bowl rotation to the feed, which drains upward by centrifugal force as soon as it hits the base of the spinning bowl (Figure 1)."

Jan 1, 2011

By Phillip I. Merritt

"IntroductionDuring and since• the war, it has been my privilege to work closely with those in Canada who are responsible for the vital raw materials needed in our co-operative atomic energy programme. The understanding which has developed between our two groups in this all-important enterprise has been a great source of pleasure. We in the United States are aware of the importance of the contribution made by Canada to this project, and we look forward to continuing our mutually advantageous relationship.The impact of World War II, and the decision by Canada, Great Britain, and the United States to join in a programme for the development of atomic weapons, created a sudden and immense demand for uranium minerals. Early in the raw materials programme, it was evident that sufficient raw materials to fulfill war-time atomic weapon requirements could be secured from three sources: the rich pitchblende deposits of the Eldorado , mine at Great Bear lake; the Shinkolobwe mine in the Belgian Congo; and as a by-product of the vanadium industry of the Colorado Plateau in the United States. In the early part of the programme, therefore, our joint efforts were directed toward obtaining immediate maximum production from these localities. The contribution made by Eldorado Mining and Refining (1944), Limited, both in supplying and refining raw materials, was and continues to be of vital importance.In addition, it was also obvious from the first that in this programme, as in any mining enterprise, exploration activities directed•toward the discovery and development of new sources of uranium ore were essential if production were to be maintained over an extended period of time. In order to satisfy obvious security requirements during the war, it was necessary to proceed with this exploration programme, both in Canada and the United States, as secretly as possible. With the end of the war, and the revelation that an atomic weapon had been developed, however, secrecy in exploration was no longer required. The important thing was to get on with a broadened exploration programme."

Jan 1, 1950

By J. E. Dutrizac

"The end of an era in zinc metallurgy took place on July 31, 1976 when the horizontal retort furnaces of the National Zinc Company in Bartlesville, Oklahoma were permanently shut down (1) . For more than a century, horizontal retorting had been the most common method of producing zinc in the United States; it was a thriving industry in many parts of that country, especially in the natural gas belts of Oklahoma and Texas. With the Bartlesville closure, yet another metallurgical process has become an object of historical interest for North American metallurgists. Although shrouded in controversy, the origins of zinc metallurgy seem to date back at least 2000 years. Pyrometallurgical methods with carbon reductants are capable of producing zinc from oxidic zinc ores, but only above the boiling point of the metal. Although slow cooling results in re-oxidation of the zinc vapour by air or carbon monoxide, quenching yields liquid zinc; some form of rapid cooling, either accidental or intentional, was likely used by ancient metallurgists to liquify the metal. Zinc metal found in Athenian objects of the Roman era was likely of accidental origin. The Romans employed brass extensively for coins and ornaments(2) , and this was intentionally produced by the calamine process whereby oxidic zinc ores were added to molten copper under strongly reducing conditions. Zinc appears to have been known in China and India as early as 1000-1300 A.D., and was probably smelted commercially in those countries from the 14th century. Although the early metallurgical procedures were probably inefficient, they were able to produce zinc metal in significant amounts. The large heaps of zinc residues with clay retorts bear testimony to an early smelting industry of impressive magnitude. It is estimated that the heaps at Zawar, India alone represent the extraction of 100 000 tons of metallic zinc(2) In the 1730s the smelting of oxidic zinc ores was developed in England using a vertical retort method. In 1788 a British patent was granted for making zinc from zinc blends (ZnS) by roasting the ore in a coalfired reverberatory furnace, mixing the calcine with charcoal and smelting the mixture with suitable zinc condensation. The English process was very energy intensive, however, and early in the 19th century the Belgians developed a horizontal retort process for the reductiondistillation of zinc that was more fuel efficient. This technique was gradually developed into what came to be known as the Belgian process, the forerunner of the ""modern"" horizontal retort furnace."

Jan 1, 1999

By R. T. Jones

"Technical publications in the field of mining and metallurgy have existed for a long time. Recent developments in electronic publishing on websites make it possible to disseminate information more widely and cost effectively than before. Professional societies have an opportunity to serve their members and their industry by publishing high-quality peer-reviewed papers on their websites as well as in printed form. Older publications can be scanned, and optical character recognition can be used to provide searchable text. Various business models exist around this process. This paper outlines the approach used by the Southern African Institute of Mining and Metallurgy (SAIMM) to provide free open access to their journal papers and conference proceedings, as well as the work being done by OneMine.org to collect technical papers from a number of international societies and make them available to subscribers via a large database. An approach is outlined that should be of benefit to authors, readers, and society at large.INTRODUCTIONGeorgius Agricola (1494-1555) was not the first writer on the subjects of mining and metallurgy, but is well known as the author of De Re Metallica (‘of things metallic’ or ‘on the nature of metals’), a book that documents and illustrates the observations he made in the course of his extensive travels in the 1500s. Agricola wrote extensively about mining methods and metallurgical processes that were in place in the Middle Ages. The original Latin version of De Re Metallica was published in 1556, the year after Agricola died. It was translated into English by Herbert Hoover, a mining engineer and later President of the United States, and his wife Lou Henry Hoover, a geologist and classicist. The English version of De Re Metallica was published in 1912."

Jan 1, 2012

By M. C. Makepeace

"It is the objective of designed experiments to obtain more information for less material and process cost than can be obtained by traditional experimentation. In this paper, the fundamental concepts on which the statistical design of experiments is based are briefly re-viewed according to the following outline: The Experiment The Design The Analysis Two simple 2"" factorial experiments are presented as examples."

Jan 1, 1967

By J. W. Baker

"The Kerr-Addison mine is on the northeast shore of Larder Lake in the township of McGarry, District of Timiskaming, Ontario. It lies just south of the highway leading to the town of Kirkland Lake, 25 miles to the west.The property was first staked in the summer of 1906, by a party of prospectors led by a Dr. Reddick of Ottawa. Subsequent assessment work resulted in the erection of a 20-stamp mill in 1908. Gold from this mill was used in the first gold coins to be minted in Canada. The operation did not prove successful, however, and mining was suspended. In 1914 a consider-able amount of underground development was undertaken by the Associated Goldfields Co., without success.In 1936 Kerr-Addison Gold Mines Co. carried out large-scale sampling from four adits driven into the hillside at the mine. Results were not satisfactory, but it was decided to drill one last deep diamond drill hole from surface. The hole cut a wide section of gold ore. With this encouragement, further development outlined a large tonnage of ore, and a 500-ton mill was put into production in May, 1938. In 1939, its first full year, the mine produced 54,480 ounces of gold and 2,732 ounces of silver. By 1955 the mill had been expanded to a rate of 4,549 tons daily, and in this year 427,193 ounces of gold and 23,490 ounces of silver were produced.From 1938 to the end of 1955 the total production, from 17,473,797 tons milled, has been 3,607,462.74 ounces of gold (0.2064 ounces per ton), and 182,278.56 ounces of silver, with a total value of $131,073,037."

Jan 1, 1949

By M. N. Bassim, W. W. Tennese

"Concepts of linear elastic fracture mechanics were applied to study two cases of failure, namely an equalizing beam from a tandem rear axle of a highway tractor unit and the main beam of a flat bed trailer. In the first case, the presence of a crack, initiated by stress corrosion cracking followed by significant fatigue crack propagation produced a state of stress which was sufficient to produce brittle failure. Calculation of the fatigue life agreed with the number of cycles that the structure experienced before final fracture. In the second case, it was demonstrated that a combination of low temperature and high loading rate was sufficient to cause brittle fracture.IntroductionFailure analysis of engineering components has generally been carried out without the benefit of fracture mechanics. It is generally understood that real structures inevitably contain internal or surface flaws which under an applied load, may propagate to fracture. Fracture mechanics relates the applied stresses to the crack size in specified geometries. Since its introduction approximately thirty years ago, fracture mechanics has evolved as a design philosophy which can be used to develop fracture-safe designs. It can be also applied in analysis of failures, to ascertain if sound design and fabrication methods have been used."

Jan 1, 1985

By J. A. Abols, P. M. Grady

Recovery via gravity is one of the oldest mineral processing methods available. Unfortunately, the use of gravity techniques for gold recovery has been in decline for the past century as more effective chemical processes such as flotation and leach/CIP have been developed. Recently, with the push towards more sustainable environmental outcomes, the benefits of gravity separation have become more apparent. While gravity as a unit process is not usually capable of achieving as high a recovery as flotation or whole ore cyanidation, a combination of gravity devices alone or in conjunction with these processes can offer significant advantages to the operator. This paper reviews the range of gravity devices available, their application and the results that can be achieved by maximizing gravity through the use of a combination of gravity recovery devices. Three case studies are provided.

Jan 1, 2005

By E. O. Abrokwah

Directionally solidified (DS) Rene 80 Superalloy was tested in thermo-mechanical fatigue (TMF) over the temperature range 500-900°C and plastic strain levels from 0.2 to 0.8% using a DSI Gleeble thermal simulator. Thermo-mechanical testing was carried out on the parent material in the conventional solution treated and aged condition (STA), as well as gas tungsten arc welded with an IN-738 filler, followed by solution treatment and ageing. Comparison of the base TMF unwelded alloy with that of the welded and heat treated alloy showed that varying crack initiation mechanisms, notably oxidation either by stress assisted grain boundary oxidation, or associated with grain boundary MC carbides fatigue crack propagation along grain boundaries and creep deformation were operating, leading to different "weakest link" failure initiation points.

Jan 1, 2011

By Marcel Labbé

La largeur de l?armature peut être modifiée selon les besoins du client entre 48 " et 64" de largeur totale, donc 2 sections de 24" à 32". Ceci permet à l?opérateur d?effectuer le démantèlement de l?équipement pour le déplacement dans les endroits restreints. Le déménagement d?un niveau à un sous-niveau devrait se faire dans un quart de travail de 8 heures. L?option de largeur permet au client de choisir un équipement adapté à son environnement de travail (1). La largeur de la table de forage peut être modifiée selon les besoins du client entre 48" et 96". Cette particularité permet une meilleure stabilité, et plus de précision dans le forage (2). Il y a 4 pattes hydrauliques à chaque coin pour la stabilisation lors de forage (3). La table de forage a 360° d?angle de forage sur 3 côtés du transporteur. La table peut sortir de chaque côté du transporteur de 40 ½" à partir du centre du transporteur pour faciliter la mise en place de la foreuse dans les endroits difficiles d?accès. La plage de forage est considérablement agrandie. Cette caractéristique qui fonctionne hydraulique, permet à l?opérateur de forer sans être obligé de changer la position du transporteur pour des changements de trous. Tous les types de foreuse peuvent être installés sur cette table de forage (4). Sa petite dimension lui permet d?accéder, par des monteries de 30" de diamètre, à des sites de travail de 2,5 mètres de hauteur et largeur. C?est un équipement adapté aux gisements filoniens. Ce genre de gisement est de moins en moins rentable pour les compagnies minières. La mécanisation des ces gisements va permettre de les rentabilisés en augmentant la productivité et la santé du travailleur, en réduisant la dilution (5). Les manettes de contrôle de la foreuse, les mouvements de la table de forage ainsi que le déplacement du transporteur ont été installés selon les recommandations d?un ergonome. Des recherches ont été effectuées par ce spécialiste sur les cas d?accident survenus avec l?utilisation de ce genre d?équipement. Il a déterminé les positions le plus confortable que l?opérateur doit prendre pour éviter les douleurs prolongées (6). Le système de roulement est composé de 4 roues pleines installées sur 4 planétaires de 9000 à 15000 livres de capacité munis chacun d?un moteur hydraulique. Des freins ont été installés sur les planétaires pour assurer la sécurité de l?opérateur et faciliter le positionnement du transporteur lors du forage. Des roues rétractables peuvent être installées pour faciliter l?accès sur rail (7). Ce transporteur peut être alimenté par une puissance électrique plutôt que par une puissance pneumatique. Cette puissance électrique est fournie par un Power Pack qui transforme l?énergie en puissance hydraulique. Ce type d?alimentation est employé lors du forage de développement, mais il peut aussi être utilisé pour le forage long trou. Cet avantage permet au client qui a un problème de pression d?air d?utiliser l?électricité. Par contre si vous utilisez l?électricité mais que dans un secteur isolé le gros courant électrique n?est pas accessible vous pouvez utiliser votre équipement en utilisant la puissance pneumatique. Le changement d?alimentation énergétique se fait facilement (8). Cet équipement est construit pour effectuer 4 types d?activités : forage de développement de niveau et sousniveau avec l?installation d?un bras porteur, forage et pose de câbles d?encrage pour soutènement de terrain, forage de production long trou et forage de monterie ascendante et descendante. L?avantage est que vous investissez dans un seul équipement au lieu de 2 ou 3. Cet avantage vous fait économiser dans votre budget d?équipement. En plus cet équipement est construit pour de dure travaux et ne contient aucun système électronique (9).

May 1, 2001

By P. Cicmanec

Mining activities in the territory of Slovakia have a long history. Mining techniques have developed rapidly in the last centuries. This paper deals not only with mining history, but also with underground brown coal mining, magnesite mining and other mining activities at present and sustainable developments of the mining industry in the Slovak Republic. This paper looks forward in the context of mineral raw materials in Europe (Global Europe, 2012).

Aug 1, 2013

ABSTRACT This paper details the work of RISKGATE, the largest Australian Coal Association Research Program (ACARP) occupational health and safety initiative to date. The program is an interactive online risk management system developed to maximize health and safety performance in the coal mining industry by implementing continuous improvement in managing major unwanted events. The comprehensive knowledge base covers tires, collisions, fires, isolation, strata control underground, ground control open cut, explosions, explosives, manual tasks, and slips/trips/falls. All major Australian coal mining companies contributed topic experts to this broad industry initiative: nine coal mining companies, more than 80 experts, and more than 400 days of individual time for knowledge-capture workshops.

Jan 1, 2014

By Jacob W. Young

A casual reading of the geological literature extant to-day would give one the impression that carbon is an element which by some chance or another always existed at or near the surface of the earth, and was never of a magmatic origin. The carbonaceous matter in shales is said to be of vegetal derivation; petroleum is stated to have been derived from vegetable matter or from marine animal bodies; if carbon or bituminous matter is found in igneous rocks or associated with metallic ores, the statement is made that deeply buried carbonaceous sedimentaries were undoubtedly the source from which such carbon or bituminous matter was derived. This, I do not consider a reasonable or common sense view of the matter. Carbon is one of the elements of which the earth is composed. In the table giving the periodicity of the elements it comes sixth in the order of increasing atomic weights. It is an element formed like all the rest were formed, and must be as common to the interior of the earth as the rest of the eighty-odd elements so far discovered. The spectroscopic analysis of light from the sun, and the stars, shows the presence of carbon in the sun and in the colder stars. Thus with carbon, an element, found throughout the universe as well as on the earth, it is entirely reasonable to consider it as present in the interior of the earth with the other elements. Such being the case, the magmatic origin for the various forms of carbon in rocks and ores is a rational and logical conclusion. If but a small fraction of thought and effort was made along these lines, which is made in fostering the idea of the organic origin of the carbon found in the earth's crust, untold advances in this phase of geological science would result.

Jan 1, 1925

By J. Bélanger, B. Semlali, M. Grenon

RÉSUMÉ La conception des fosses ainsi que l'évaluation des ressources géologiques et des réserves minières sont désormais réalisées entièrement à l'aide d'outils informatiques spécialisés. Cependant, plusieurs analyses, pourtant essentielles à l'évaluation de la viabilité du projet, sont réalisées en parallèle sans véritable optimisation ni synergie avec l'ensemble des données disponibles. Cet article présente deux approches permettant d'intégrer certains types d'analyses aux modèles de blocs miniers. Ces approches permettent de quantifier la broyabilité du massif rocheux ainsi que d'étudier la stabilité des pentes minières à même les outils d'optimisation et de planification minières. Cette méthode permet dès l'étude de faisabilité d'un projet minier de maximiser les données disponibles, menant ainsi à une approche plus intégrée en conception minière. De plus, ces approches sont flexibles et permettent d'évaluer rapidement plusieurs scénarios, tout en laissant la possibilité de bonifier le modèle et de revoir la conception tout au long du projet minier.

Jan 1, 2010