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By A. E. Cameron

The theory of atomic distribution of the stranger atoms in the space lattice of the solvent metal has been well developed by Rosenhain. It has long been known that the addition of one metal to another to form a solid solution increases the strength and hardness of the solvent metal. This increase is practically proportional to the amount of added substance up to the limit of solid solubility. To account for this increase in hardness and strength, Rosenhain assumes that the stranger atoms occupy positions on the solvent metal space lattice. Atomic attractions about the stranger atoms will not be the same as in the case of the pure metal, and there will thus be a disturbance of the orderly arrangement of the atoms on the space lattice, or a distortion of the lattice. Such a disturbance would interfere with the ease of slip along the planes and would thus tend to promote strength and hardness. Rosenhain notes that not only may there be a local disturbance of the lattice about the stranger atom but there may well be also a measurable change in the dimensions of the lattice as a whole. The relative amounts of local and general distortion of the lattice will depend upon the nature of the lattice itself. As Rosenhain says, "If the lattice is comparatively soft and flexible the distortion is likely to be largely local. In a stiff lattice, however, local distortion will be resisted and there will be a correspondingly increased general distortion."

Jan 1, 1927

By S. Boisvert

Risk-based Inspection (RBI) addresses the challenges associated with ageing plants by focusing the inspection effort on the process equipments with the highest risk, thereby improving plant safety and reducing inspection costs. The RBI methodology is commonly used in the oil industry through the API 581 standard. Since no such standard exists in the mining and metals industry, BPR-Bechtel has developed one using inspection data from process equipments in CEZinc. Models were developed for various damage mechanisms, such as uniform corrosion and stress corrosion cracking. The equations were organized into a user friendly software that facilitates the implementation process.

Jan 1, 2010

By J. P. Messervey

THE story of the efforts made by the Department of Mines of Nova Scotia in the search for and investigation of mineral resources for the Canadian war effort began in the spring of 1937. During the past five years, however, heavy enlistments in the Active Service Forces by employees of the mining industry of the Province caused a recession in the production of coal, salt, and other essential minerals required to keep industry rolling on a wartime basis. A marked increase was shown during the period in prospecting for 'strategic' minerals, not only by individuals but also by some of the foremost mining companies. The Provincial Government offered encouragement in this field of endeavour by the enactment of legislation whereby the prospector was enabled to secure the maximum area of ground in a prospecting license at a minimum of cost. The labour requirements on the ground staked, however, remained unchanged. The Nova Scotia Department of Mines continued active investigation of minerals vital to the war effort. These included fluorspar, barytes, diatomite, limestone, and coal. Fundamental knowledge concerning the geology and mode of occurrence of these minerals was accumulated and extensive diamond drilling was carried out on the promising occurrences. Work in these fields is being continued.

Jan 1, 1945

By Horace Freeman

"IN THE writer's opinion, the most important industrial re-search problems in Canada concern development of technology for the treatment and commercial utilization of the recent discoveries of v.ast quantities of easily concentrated iron ores in both eastern and western Canada. They exist in both magnetite and hematite forms. The subject is doubly important because of the lack of metallurgical coking coal in Canada. Methods for utilizing our lower grade eastern and western coals for reduction purposes must be developed. We are fortunate in our supplies of oil and gas, which can supply the heat requirements for processing or for thermal electric plants, which are now competitive with hydro-electric plants in the industrial areas. These are among the reasons which have prompted the writer to continue the development of the co-current rotary kiln direct-reduction process outlined •in his report to this Institute at the 1956 Annual Meeting ( 1) in the face of the scepticism which has surrounded the numerous costly failures in 'sponge' or 'direct' iron production. The work involved in bringing the concentrating ores of Canada to the metallic state involves, firstly, concentration of the ores; secondly, preparing the concentrates for reduction; thirdly, reduction of the 'reconstructed' ore; and finally the steel making process. These briefly will be dealt with in order, giving emphasis to the most important of these steps, the reduction process which is the main subject of this paper."

Jan 1, 1959

By L. Chunpongtong

The Athabasca oil sands mineable resource is located in northeastern Alberta, Canada. In oil sands mining, the ore zone is regulated to have a minimum mining thickness of 3 m and a cutoff grade of 7 wt.%. The current algorithm that is widely used to flag ore zones and waste zones tends to overestimate oil reserves and causes low-grade ore to be processed. This paper presents the development of a more complex algorithm that is more representative of the actual oil found during operations and that can prevent low-grade ore from being sent for processing.

Jan 1, 2014

By P. H. Shipway, D. G. McCartney, H. Saghafifar

The microstructural changes during thermal ageing at 650ºC in the interfacial region of Alloy 625 weld overlay on a 2.25Cr-1Mo steel was evaluated. Optical microscopy, scanning electron microscopy in SE and BSE modes, electron probe microanalysis and hardness mapping were used to characterize as-welded microstructure and its changes during thermal ageing and precipitates of interfacial region. Carbon migration across the interface was recognised as a major issue. A region of 300 µm wide adjacent to the fusion line, which was found harder in the as-welded condition decarburized during thermal exposure. Studies revealed that this region transformed to a soft region containing large ferrite grains and micron-sized carbides. In the weld overlay, a 50 µm wide hard band (over 650 Kgf mm-2) adjacent to the fusion line formed and carbide precipitates were observed along grain boundaries. Carbide precipitation mostly occured in the 150 µm wide region close to fusion line.

Jan 1, 2017

By J. L. Jambor, E. J. Reardon, E. C. Appleyard, J. A. Cherry

Since the 1957 initiation of deposition of mill tailings at the Heath Steele mine, New Brunswick, periodic detailed studies of the tailings geochemistry and mineralogy have been conducted, thereby providing a unique opportunity to examine the geochemical evolution of a sulfide rich mine>tailings impoundment. When deposited, the tailings contained about 85 wt% sulfide minerals, 1 wt% to 3 wt% carbonate minerals, and 12 wt% to 14 wt% alumino silicate minerals. Mineralogical examination of samples of the tailings from deep in the impoundment indicates that little oxidation occurred prior to tailings deposition. The mill process-water deposited with the tailings was neutral to slightly basic and contained low concentrations of Cu, Pb, Zn and As. Sampling of the tailings five years after deposition indicated that sulfide-oxidation reactions, occurring near the tailings surface, had decreased the tailings-water pH and increased the concentrations of Fe, S042-, Cu, Zn and Pb (up to 10 000 mglL, 25 000 mg/L, 2.5 mg/L, 200 mg/L, and 4.5 mg/L, respectively). In 1975, ten years after decommissioning, the tailings could be divided into three zones: an upper oxidation zone in which sulfide oxidation is actively occurring, a hardpan layer, 15 cm to 20 cm thick, composed of tailings cemented by secondary Fe minerals, and an underlying reduction zone in which the tailings are relatively tin oxidized (Boorman and Watson, 1976). Chemical analyses indicated the presence of low-pH waters containing very high concentrations of SOi-, Fe, and other metals (up to 63 600 mg/L SO42-, 28 600 mg/L Fe, 10 mg/L Pb, 600 mg/L Cu and 4000 mg/L Zn), suggesting that there was a period of intense sulfide oxidation between five and ten years after tailings deposition. More recent sampling, conducted some 20 years after the end of tailings deposition, indicates that relatively little change has occurred in the last ten years, thereby suggesting that the hardpan layer has provided an impediment to the downward movement of dissolved constituents. Analyses of the tailings solids show increased accumulations of many metals at or near the depth of the hardpan layer. Evaluations of the long-term evolution of the tailings can be enhanced by comparison of descriptions of the tailings with descriptions of the gossan that overlay the massivesulfide orebody prior to mining. At Heath Steele, this comparison suggests that many of the mechanisms controlling the distribution of metals in the tailings will probably persist over geologic time.

Jan 1, 1992

By Eric Johnson

"IntroductionHistoricalCyanidation is a leaching process, in world-wide use, to extract gold (and silver) from ores and concentrates. The process has many inherent advantages on account of its adaptability:a. to any scale of operation;b. to a wide range of ore types and mineral associations;c. to a wide range of physical characteristics of the gold particle size, alloy (electrum) or mineral (telluride);d. to relatively simple plant controls and operating procedures;e. to simple marketing procedures and quick cash return.The basic idea for cyanidation was first described and patented by a German chemist, L. Elsner, in 1846. Some forty years later, J.S. McArthur, a metallurgical chemist and R.W. and W. Forrest, medical doctors, all of Glasgow, Scotland, came to realize the import of the discovery and accordingly, registered patents in Great Britain in 1887 and in the United States in 1889. The keystone of the McArthur-Forrest patent registration was the use of weak (0.05o/o) instead of strong (1.0%) solution.The years 1890-1910 saw much progress in equipment design and the advance from batch to continuous processing to increase efficiency and reduce operating costs.In later years, technological progress followed advances in materials of construction and control systems. Current innovations include large-scale equipment, high-capacity thickeners, belt type filters and Steller, candle-type filters for plants using zinc dust precipitation. As well, environmental protection is increasingly a major concern.The technology of gold adsorption from cyanide solution onto activated carbon has made rapid strides in recent years. This has followed the initial efforts of Potter, Salisbury, Zadra and their colleagues of the U.S. Bureau of Mines Research Station in Salt Lake City, Utah, and the field work of Homestake Mining Company personnel, in Lead, South Dakota."

Jan 1, 1989

By V. Feldman, I. Holl, J. Zampini

"The Renard Mine, 100% owned by Stornoway Diamonds, is located approximately 250 km north of the Cree community of Mistissini and 350 km north of Chibougamau in the James Bay region of north-central Québec. The project benefits from a large and growing resource, good mining conditions, strong social acceptance, a modest environmental footprint, and the development of direct-to-mine road infrastructure. Construction began on July 10, 2014; following the completion of a 946 million CAD project financing transaction. Now completed, the mine is the first diamond mine in Québec, and one of only six in Canada, employing approximately 500 people. First ore was delivered to the plant approximately 5 months ahead of schedule on July 15, 2016. Commercial production was declared on January 1, 2017. In general, the project ramp up has been characteristic of a type 1 McNulty curve. One of the challenges during production ramp-up was a redesign of processed kimberlite dewatering (replacing the dewatering centrifuge with two stages of hydrocyclones and a dewatering screen). A processing opportunity captured by Stornoway was the design and installation of an ore sorting facility which rejected free waste rock from the valuable host rock; kimberlite. Through tackling both challenges and opportunities, Stornoway has realised and is now exceeding their original design tonnage.PROJECT DESCRIPTION Stornoway Diamond Corporation (Stornoway) was established in 2003 resulting from to a plan of arrangement between Northern Empire Minerals Ltd. and Stornoway Ventures. In 2011, Stornoway acquired 100% interest of the Renard Mine. The construction of the Renard Mine began in 2014 and achieved full production in 2017 [1, 2]."

Jan 1, 2019

By Patrick Chabot

Ce document présente une méthode hybride de long trou favorisant une méthode de minage initiale par chambre-magasin et complétée par une méthode de minage long trou. Cette méthode a été adaptée suite à plusieurs facteurs tels qu?une géologie complexe, une rareté de mineur d?expérience et un haut taux de roulement de main d?oeuvre spécialisée. Cette méthode a permis d'excellents résultats par rapport à la dilution. De plus, la récupération de pilier à haute teneur par forage long trou sera expliquée. Cette méthode permet aussi de récupérer le minerai qui est resté accroché dans les chantiers chambre-magasins. Introduction : La mine Géant Dormant est une mine filonienne d?or située à environ 80km au nord de la ville d?Amos au Québec. Elle est en opération depuis 1988 et à la fin de 2007, elle a produit près de 885 000 onces d?or à partir d?environ 2 400 000 tonnes de minerai pour une teneur moyenne d?environ 11,5g /t Au. Cette mine est la propriété d?IAMGOLD Corporation depuis l?acquisition de Cambior par cette dernière au mois de novembre 2006. Elle emploie 151 employés permanents et environ 41 entrepreneurs.

Feb 1, 2008

By G. Avramovic-Cingara, H. J. McQueen

The microstructure of commercially pure aluminum was investigated by using polarized optical microscopy (POM), orientation imaging microscopy (OIM), and transmission electron microscopy (TEM) techniques. Specimens were deformed in torsion at 400°C and equivalent strain rate of 0.1 s-1, to various strains of 0.2, 0.5, 1, 4, and 6. The results indicate that POM can usefully reveal grain and subgrain structures over a large field in aluminum. TEM is most suitable to study dislocation substructure and evolution of subgrains. While TEM microscopy and OIM are capable of resolving individual subgrains, OIM can not reliably distinguish subgrains with small misorientations, particularly in samples with low strain. On the other hand, the OIM technique is very useful in the analysis of many regions surrounded by high, medium, and low angle boundaries (HAB, MAB, LAB). Various misorientation maps were studied using different data processing methods. The analysis revealed that the subgrain size is relatively insensitive to strain. The fraction of low LAB ( < 5°) decreased and HAB (>15°) increased conversely with increasing strain, whereas MAB (5-15°) remained stable. The development of an increasingly bimodal grain boundary misorientation distribution is consistent with the predominance of dynamic recovery (DRV) in the evolution of microstructure, combined with geometrical dynamic recrystallization (gDRX), now called grain-refining DRV.

Jan 1, 2006

By Joey R. Kish, Shooka Mahboubi, Hatem S. Zurob, Gianluigi A. Botton

The kinetics of the Cr2O3-based scale oxidation and volatilization were studied in the presence of water vapour (H2O). A commercial Cr2O3-based scale forming Type 310S stainless steel was examined at the ambient pressure (0.1 MPa) and 550ºC in relatively low and high H2O containing environments of air- 10% H2O and air- 70% H2O, respectively. The increase in the partial pressure of H2O (pH2O) from 10% to 70% resulted in transition of the oxidation and volatilization kinetics from the parabolic rate law for air-10% H2O to the paralinear rate law for air-70% H2O. The kinetics transition was attributed to the increase in the Cr loss rate from the base scale after coupons exposure in air- 70% H2O. The significant role of the Mn alloying element in the base scale protectiveness was also discussed in the context of the Cr2O3-based scale stability.

Jan 1, 2017

By Donald P. MacKinnon

"This paper is a commentary on selected trends within the transportation industry.In general, innovations are taking place within all modes of transport (road, rail and water) serving the industrial minerals industry which will affect future distribution patterns, methods and costs. Significant technical innovations in the transportation of solids by• pipeline will also appear, perhaps in the near future, permitting the transport of specific commodities, including some industrial minerals. However, the timing and magnitude of the commercial exploitation of solids pipelines are heavily dictated by marketing factors and distribution system logistics, as well as by the innovations likely to take place within competitive modes of transport. Competitive technological developments will include increased ship capacities, improved bulk-handling facilities, larger and specialized bulk-handling rail equipment, unit trains, containerization, larger ""off-highway"" vehicles and greater inter-modal integration. Equally significant are some ""soft-ware"" techniques such as the growing interest in total distribution cost concepts. However, the impact of the developments will not be spread uniformly over all Canadian industrial minerals."

Jan 1, 1967

By T. Richard Davies

This paper primarily deals with the application of wearfacing materials and their role within a well-established preventive maintenance welding program. Some examples are shown, as well as a synopsis of possible benefits and a compendium of methods and materials.

Jan 1, 1979

By Bruce Macdonald

Operational monitoring of slope stability can be achieved by space based InSAR monitoring platforms. Natural and man-made rock slopes are monitored using a novel stack-based InSAR method that exploits both persistent point scatterers (PS) as well as coherent distributed scatterers (DS) such as areas of pavement and sparsely vegetated surfaces. The new method, Homogenous Distributed Scatterer (HDS)-InSAR identifies InSAR targets by using adaptive multilooking of statistically homogenous pixel neighbourhoods combined with thresholding the differential temporal coherence of each target candidate with respect to its surroundings. HDS-InSAR preserves PS and therefore forms a direct generalization to our proven DualScale-PSI method. The density of HDS exceeds that of PS by more than an order of magnitude often providing essentially continuous coverage over urban and industrial landscapes featuring a mix of infrastructure with mostly bare soils or rock surfaces. The improved coverage enables better definition of surface motion and underlying geology, which will lead to superior interpretation of the geophysical mechanisms causing the surface deformation, e.g. through improved integration with 3D deformation modeling. We illustrate the performance of our new HDS-InSAR method compared to DualScale-PSI using displacement results from Vancouver, Canada; Bingham mine, USA; and the Palabora mine, South Africa.

Jun 1, 2012

By J. W. Scott, G. G. R. Falkenberg

"The Syncrude project is an integrated complex designed to mine, extract and upgrade bitumen from the Athabasca tar sands to produce 129,000 barrels per day of synthetic crude oil. This paper provides a brief general description of the location, history and geology of the tar sands and the overall organization and structure of the project. The major emphasis and the bulk of the detail presented deals with the extraction plant; a material handling and mineral processing installation designed to treat 312,000 tons per day of tar sand feed.History of the Tar SandsThe Athabasca tar sand deposit was recorded in 1788 by Peter Pond, however the first serious geological mapping and exploration did not begin until 1915. Little interest was taken in the deposits until the Second World War, when the governments of Canada and Alberta conducted an extensive exploration program. In addition a number of pilot plants were sponsored during the 1940 -1950 decade. The hot water separation process was successfully demonstrated on the pilot plant scale during 1948 -49, and was established commercially in 1967 in the G.C.O.S. plant. The Syncrude plant, due to come on stream in April 1978, also employs the hot water separation process."

Jan 1, 1978

By J. K. Atherton

If the metals sector is to contribute successfully to sustainable consumption we must adopt principles and practices which address the entire life cycle of the materials we produce. Progress must be founded on a sense of shared responsibility for the resources we utilize and the materials we create - it is this integrated approach which lies at the heart of materials stewardship. Materials stewardship means mining and metals companies producing materials in a responsible manner and then working with others, beyond their site, to ensure that the downstream material flows and applications are managed properly to create maximum societal value. In September 2006 ICMM published &apos;Maximizing Value: Guidance on implementing materials stewardship in the minerals and metals value chain&apos;. This document takes a practical view presenting structured guidance as well as good practice case studies. In the publication, materials stewardship is described in terms of the range of activities that can be undertaken to ensure that all parties work collectively toward the responsible use of metal and mineral resources. This paper introduces the materials stewardship concept as set out in `Maximizing Value&apos; and describes the business case for implementation as well as the ICMM framework for promoting materials stewardship.

Jan 1, 2007

By David A. Orava, Richard C. Swider

"The technical knowledge and practical experience accumulated by industry and others in abating acid mine drainage (AMD) is being proactively applied at every phase of the mine life cycle. This paper traces the mine life cycle from exploration to post closure monitoring and maintenance, and reviews AMD abatement measures that have become an integral component of exploration and mining activities.Attention is increasingly being given to evaluating AMD potential as part of exploration work, and studies related to project feasibility and design. Mining, mineral processing, and waste management options are selected taking into consideration their suitability to inhibit AMD. These inhibition measures are typically committed to in closure plans submit-ted at the permitting stage. Mines are operated and decommissioned, often progressively, as planned and in accordance with environ-mental protection policies."

Jan 1, 1996

By K. Ihara, R. Akiyoshi, Y. Takaki, S. Kang, H. Shishido

"Tensile tests and scanning electron microscopy-electron backscattered diffraction (SEM-EBSD) analysis were performed in an Al-Mg-Si alloy to clarify the effect of annealing and cold-rolling reduction on the texture formation. The hot-rolled specimens were cold-rolled with the reduction of 58-75%(CR1), followed by annealing at 773 K for 5 min(IA). The secondary cold-rolling(CR2)for the IA specimens with the reduction of 33–66%, followed by the solution heat treatment(ST), were performed. Focusing on the CR1 and CR2 specimens, the average r-values increased with higher primary and lower secondary cold-rolling reduction, respectively. This was considered to be due to the increase of r-values measured in the direction of 45 degree with respect to rolling direction, caused by the formation of the ß-fiber components (Brass {011}<211>, Copper {112}<111> and S {123}<634>) with high density. Based on the texture analysis of annealed specimens it was suggested that the high density of the ß-fiber components after IA and the small amount of stored strain energy of CR2 introduced by the lower cold-rolling reduction remained the ?-fiber components even after solution treatment.INTRODUCTION Al-Mg-Si alloys have been applied to automobile body applications, due to their excellent paint-bake hardening (age-hardening) and corrosion resistance compared to other aluminum alloy. On the other hand, the mechanical properties and deep drawability of Al-Mg-Si alloys are inferior to those of steels. Thus, it is important to improve the mechanical properties and deep drawability in order to expand the application components. One of the best methods to improve the deep drawability is to increase the Lankford coefficient (r-value). Previous studies reported that the increase of the average r-value ( ) improves the deep drawability. The relationship between the r-value and texture of the alloy is also well known. Inoue et al. reported that the ß-fiber components, such as Brass ({011}<211>), Copper ({112}<111>) and S ({123}<634>), increase the r-value measured in the direction of 45o with respect to the rolling direction. r"

Jan 1, 2018

By P. R. Geoffroy

Extensive and Intensive Prospecting As often pointed out, the search for new ore deposits may be carried on along two widely divergent lines. It may be either extensive or intensive. By extensive prospecting we mean a search for mineralized outcrops conducted over large and more or less virgin tracts of land, followed by a test of the practical value of any discovery made, the test being limited to the immediate vicinity of the outcrop. Extensive prospecting, was, in fact, the only policy known to the early prospectors. of the American continent and is still the rule in the remote sections of the Canadian Shield and in the African wilderness. It can be further characterized by the lack of emphasis placed on geological and other technical means as an aid to the search for ore. However, very little virgin ground is left, nowadays, for a man or a company to test their luck, and whatever is left is so remote from the necessary means of development that any new discovery will require considerable delay and expenditures to be amenable to profitable mining. On the other band, a great many of the favourable and still unexplored areas (and this is particularly true in Canada) are overburdened to such an extent that outcrops of bed-rock are extremely scarce and extensive prospecting is nearly impossible. Intensive prospecting, to the contrary, must be understood as a detailed search for ore carried on over limited areas in districts already known to be mineralized and covering regional structures whose relation to mineral deposits bas been estahlis.hed with a fair degree ot certainty. The search for deep-seated deposits in the vicinity of successful mines is a perfect example of intensive prospecting. As a matter of fact, the majority of the geologists employed by the mining industry are engaged in some kind of intensive prospecting.

Jan 1, 1950