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By Scott Beer

What New Technologies Will Drive Economic Improvements? ??Historical ?1060?s: Mainframe Technologies ?1970?s: Mini Computing ?1980?s: Workstation Computing ?1990?s: Personal Computing ?2000?s: Network Computing Internet PDAs Cellular phones ??What?s the next technology improvement? ??What?s next for Mining?

May 1, 2009

By Saravarim A.

"The aim in flotation systems is to control the grade and recovery of the product., numerical method or sampling and analysis is used to achieve this goal. Weakness of measuring instruments, lack of process knowledge, deficiencies in management and data processing in the control of flotation cells, has led the academic and industrial units to use numerical models. In this regard, using the results obtained from the experimental design carried out in the DTP line of Gol Gohar industrial and mining complex, a regression model was developed based on the analysis of variance. To present this model, after variance analysis of factors and interactions, all models were investigated and the final model was created based on 75% of the data. The model was tested with the remaining 25% of the data to confirm the goodness of the fit. The coefficient of determination for training and testing resulted 71% and 74%. Moreover, a feed forward back propagation neural network with different layers and neuron was used to model the results. The best network structure was 6-27-1 and the coefficient of determination for this network was 99% and 98% for training and test respectively. Given the complexity of neural network models and the relatively low accuracy of the regression model, neural network has a priority assuming we have access to a specialist. In addition, the results obtained from neural network can be used as expert systems to control and optimize the flotation cells.INTRODUCTIONThe primary objective of the flotation cell control is to maintain the product's (in this case tailing) recovery and grade, which represents the index for process efficiency and product quality. Continuous estimation of these indexes requires a significant amount of maintenance, and calibration of the continuous analyzers, in order to maintain an acceptable level of accuracy. Weakness of measurement equipment, lack of process knowledge and the general deficiency in management and processing of data in the flotation cell control, will lead industrial units to use smart methods such as mathematical models, regression and neural networks in near future (Panahi, Abdollahzadeh, & Sam, 2010). Artificial neural networks are inspired by the very complex structure of human brain in which millions of nerve cells solve problems or store information by communicating with each other. The duty of neural networks learning. It should be noted that learning in artificial neural networks is limited, and what is practically considered is the computing power of the network. A neural network consists of units called neurons, and has the capacity to handle a set of input data to produce a desired output data set. Each of these input and output data sets can be assumed as a vector (Soltanmohammadi & Noparast, 2006)."

Jan 1, 2016

By Keith Donovan

Why are we here? Improve equipment performance & health ? Eliminate undesirable downtime and expensive secondary damage ? Maximize equipment life, optimize running costs (reduce costs) ? Improve safety and environmental performance ? Capture and consistently apply equipment knowledge ? Improve Proactive Maintenance processes & practices

May 1, 2009

By E. Fiset, T. Hennebel, F. Verbruggen, A. Prévoteau, K. Rabaey

Arsenic (As), bismuth (Bi) and antimony (Sb) are known to affect the quality of copper deposits in copper electrowinning operations. The codeposition of As was previously believed to occur only at current densities far exceeding the range of typical current densities for copper electrowinning. In this study, we investigate the copper electrodeposition on different pretreated stainless steel (SS) substrates from bleed electrolyte in galvanostatic mode at –45 mA/cm². Scanning electron microscopy (SEM) micrographs illustrate that during the initial phases of copper nucleation and growth, the current density was locally increased due to the pretreatments. It was reasoned that the codepostion of As could possibly occur in normal electrowinning conditions, but the risk can be substantially reduced by good SS substrate handling and maintenance practices. INTRODUCTION The presence of As, Bi and Sb is known to have a deleterious effect on the copper cathode quality in copper electrowinnings (Hiskey & Maeda, 2003; Hoffmann, 2004; Xiao, Cao, Shen, & Volinsky, 2012; Xiao, Cao, Mao, Shen, & Ren, 2014; Jafari et al., 2017). They are known to influence both the chemical and physical quality of the copper as they can contaminate the copper (Jafari et al., 2017) and affect the copper deposit structure (Hiskey & Maeda, 2003; Kim, Kim, & Chung, 2009), which contributes to a degraded market value of the copper (Tuddenham, 1984). The incorporation mechanisms of these impurities are believed to occur mainly through slime inclusion (F. Xiao et al, 2012) and electrolyte inclusion (Hiskey & Maeda, 2003). Other studies suggested that codeposition of these impurities is possible by their standard reduction potential being close to the one of copper (Xiao et al, 2014). Hiskey and Maeda (2003) investigated the copper electrodeposition on a copper electrode substrate in Cu electrolytes with a Cu, H2SO4, As, Bi, Sb composition representative for commercial copper tankhouses. The combination of voltammographic techniques and Auger electron spectroscopy showed that As was the first impurity to be electrodeposited from this electrolyte, yet at potentials where the limiting current density of the copper electrodeposition reaction is exceeded. The copper tankhouses usually operate at a current density ratio of 0.3 to the limiting current density in order to achieve tolerable copper quality deposits. The codeposition of As could be considered impossible in this current density condition. However, it is known that during the initial phases of electrodeposition on foreign substrates, a substantial part of the reaction proceeds by growth of individual nuclei where the current density is locally high and diffusion limited (Radisic, Ross, & Searson, 2006). Furthermore, it was observed that copper nucleation on TiO substrates occurred preferentially in the scratched oxide free areas which could serve as parts with high localized current densities (Chang, Choe, & Lee, 2005).

Jan 1, 2019

By H S. Ellis

Flow studies have been conducted on nickel-water suspensions in a 1in.-diam., 42-ft.-long transparent lab-oratory pipeline at concentrations of up to 25 per cent, by volume, and slurry velocities of up to 15 ft/sec. The average size of the nickel powder was approximately 150 mesh (106J.L). Three flow regime were noted. At the highest velocities, i.e., above 10 ft/;sec., where the concentration distribution through the vertical diameter was most uniform, pressure gradients could be correlated with the Durand-Condolios equation (7,8). An intermediate region, i.e., from 7 ft/sec. to10 ft/sec., could be distinguished, the lower velocity limit being that at which nickel particles began to deposit. This region was also marked by decreasing pressure gradients, for a given concentration, as the velocity was reduced. The upper velocity limit in this region was also uniquely defined in that the friction factor for any nickel concentration was the same as that for water. In the third regime, below about 7 ft/sec

Jan 1, 1963

By Martin Bergeron

Producteur d?or de taille intermédiaire Mines Aurizon Ltée Bureau-chef àVancouverMine et projets localisés au Québec2

May 1, 2011

By E. V. Konopleva, H. J. McQueen

Steels in high variety have been providing strength and ductility for more than a century mainly through complex heat treatments following hot shaping. The economical and sustainable goal was a steel with the two operations combined through applying knowledge of dislocations and strengthening mechanisms aided by new mechanical and microstructural techniques. Primary hot reversing-mill rolling produced static recrystallization (SRX) between every pass to significantly finer grain size. Hot torsion showed that with lay-on temperature and rate of reduction suited to gradual precipitation of minor additions of Nb, the austenite grains would become highly pancaked; the existence of very fine subgrains along the grain boundaries (GB) could be deduced from tests on stainless austenite. The HSLA strip had to be water-jet cooled immediately to prevent SRX at austenite GB and ensuring complete transformation to ferrite avoiding grain growth after coiling. Confirmation on old mills and successful product led to the design of more flexible mills for wider range of compositions and products. A significant one was auto bumpers that reduced crash damage. More crack-resisting compositions were developed for strip welding into line pipe for arctic oil transport. Lower metal consumption and easier fabrication has resulted in more sustainable welded bridging.

Jan 1, 2015

By M. B. Kime

"Discrete-element method (DEM) modelling is a powerful tool for studying particulate systems within the mineral processing industry. DEM simulations were conducted to investigate the power draw, load behaviour, and impact energy profile of an experimental ball mill under different milling conditions. The variables considered were mill rotational speed (percent critical speed), ball size, and lifter face angle. The simulation results indicated that the grinding efficiency would be enhanced by using 80% critical speed, 30 mm ball diameter, and 45° lifter face angle. These findings can be useful in guiding actual ball milling tests involving an ore sample.RÉSUMÉ La modélisation par méthode des éléments distincts (MED) est un outil puissant qui permet d’étudier les systèmes particulaires au sein de l’industrie de traitement des minerais. Des simulations par MED ont été menées de façon à étudier le profil de la consommation énergétique, du comportement de la charge et de l’énergie de rupture d’un broyeur à boulets expérimental dans diverses conditions de broyage. Parmi les variables prises en compte figuraient la vitesse de rotation du broyeur (vitesse critique en pourcentage), la taille des boulets et l’angle de coupe de la cornière élévatrice. D’après les résultats de la simulation, on pourrait améliorer l’efficacité de broyage en utilisant une vitesse critique de 80 %, un diamètre de boulet de 30 mm et un angle de coupe de 45 ° de la cornière élévatrice. Ces résultats peuvent se révéler utiles pour les essais concrets de broyage à boulets impliquant un échantillon de minerai."

Jan 1, 2017

By J. Zhang, T. Oleniuk

It is well-known that Saskatchewan has the world’s richest uranium deposits and advanced processing technologies. Unlike the Saskatchewan deposits, complicated mineralogy is common for other places in the world. Mineralogy dictates the process. Mineral Processing at the Saskatchewan Research Council has been working with the uranium industry worldwide since its inception to develop effective processing technologies to suit the unique mineralogy of each deposit. This paper reviews the research and development of uranium processing technologies in the current major uranium production areas such as Canada, as well as the potential development regions like Argentina and Sweden. Acidic and alkaline leaching processes, as well as by-product recovery technologies are discussed based on mineralogy.

Jan 1, 2020

By M. Bustin, A. Hosseinian, G. Preisig

Hydraulic fracturing and hydraulic shearing techniques are essential for the development of unconventional oil & gas and geothermal resources. Such techniques will also play a key role in the development of CO2 sequestration, and management of high stresses encountered with deep mining. However, the optimal design of hydraulic injections is often limited by continuum treatments of the rock mass without consideration of the influence of the natural fractures present. These may interact with the hydraulic fracture to promote offsets or arrest, or may cause the natural fractures to undergo shear and dilation. Given the limited access to the rock afforded by deep boreholes common to oil & gas and geothermal projects, advanced numerical modeling is critical for understanding key mechanisms and interactions. In this work, we first present a coupled hydromechanical distinct-element model focusing on the propagation of a hydraulic fracture. Normal and shear displacements arising from the generated hydraulic fractures are subsequently integrated into a fracture flow model for detailed analysis of specific flow behaviour and fracture permeability. For this, a scanned 3-D profile of a natural fracture is used to correlate surface roughness to dilation as a function of shearing. Fracture flow is computed at different time steps corresponding to different fracture propagation states and geometries. Modeling results indicate that the opening of a tensile hydraulic fracture is accompanied by millimetre-scale shear displacements associated with slip and wedging between adjacent blocks. This may leads to a mismatch between the upper and lower walls of the fracture if asperities are irregular and strong enough. However, fluid-induced tensile fractures have low Joint Roughness Coefficients (JRC), and associated millimetre-scale shear displacements are too small to ensure a significant offset of asperities that prevent a fully-elastic closure when the hydraulic fracture is depressurized. Injection of proppant is thus critical to keeping hydraulic fracture apertures open. Future work is planned that will see the models calibrated against field data including microseismic event locations, magnitudes and source mechanisms, tiltmeter deformations, stress change, and pore pressures.

Jan 1, 2015

By L. Heber Cole

Introductory During the past few years, salt (sodium chloride) strata have been encountered in western Canada in a number of wells, while prospecting for oil and gas. The ever increasing number of such wells points to the presence of a vast salt basin, the boundaries of which are at present unknown. This basin extends in a northwesterly direction from a point near the United States boundary south of Regina, crosses the Saskatchewan- Alberta boundary northwest of Unity, Sask., and continues with more northerly trend to Waterways and beyond. The beds, as encountered, appear to have a general dip to the southwest of between 10 to 20 feet to the mile and a pitch along the strike to the southeast. Thus one finds the salt strata at Waterways, Alta., at 600 feet below the surface (121 feet above sea level) whereas at Radville, Sask. south of Regina, the top of the salt is at a depth of 6,643 feet below the surface (4,430 feet below sea level). Whether this is a continuous salt basin or a series of separate basins is not yet known. We do know however, that in some of the well~ more than one salt horizon occurs while in others which normally should have encountered corresponding beds, the salt strata are absent. This latter condition, however, may occur only in the southern part of Saskatchewan, where a barren area seems to come in from the southwest. In the northwestern part of the basin, on the other hand, the occurrence of the salt strata seems to be more regular and continuous, and depths at which salt should be encountered in a drill hole in this part of the basin may be predicted with a fair degree of accuracy.

Jan 1, 1948

By A. Ignatieff

This is the first in a series of Coal Technology Reviews being prepared in accordance with a recommendation voted by the Coal Division in session at the Jubilee Meeting, Vancouver, April, 1948, that the Department of Mines and Resources be requested to arrange for publication by the proper Government authority of a Quarterly Review' of Coal Technology, for distribution among those concerned in the production and use of coal in Canada. This recommendation was subsequently endorsed both by the Council of the Institute and by the Dominion Coal Board. Further reviews (or digests) will appear at intervals in the Bulletin, or will be published and distributed by the Board which, meanwhile, has undertaken to distribute reprints of Mr. Ignatieff's review.-En. * * * The fields in coal mining technology which are considered to demand most attention and study at the present time are reviewed under the headings appearing below. Mechanization In the light of the growing shortage of skilled miners and the necessity of mitigating constantly increasing mining costs, interest continues to centre in mining methods and applications of mechanization chat will produce the maximum reduction of man power. The growth of strip or open-cut mining, also, is a consequence of this trend. Mechanization at the face attracts most attention and the trend is toward developing and adopting machines capable of cutting and loading the coal in one operation instead of having the separate operations of cutting, drilling, blasting, and loading. In Great Britain, where longwall mining is? the general practice, the A.B. Meco-Moore machine still receives much attention, and accounts describing its performance over reasonably long periods have appeared in the technical press.

Jan 1, 1948

By Richard N. Zimmer

This paper discusses the installation of corrugated steel linings in bored raises at Inco's Thompson Mine. The procedure for the installation of these linings is outlined and the relative advantages are compared with conventional methods of ground support. Future trends in the use of corrugated steel products are then discussed.

Jan 1, 1978

By Gregg W. Morrison

"The Craigmont copper-iron skarn deposit is adjacent to the southern margin of the late Triassic Guichon Creek batholith in south-central British Columbia. Host to the ore are sedimentary and volcanic rocks of the western calc-alkaline belt of the Upper TriassicNicola Group. In the mine area, the Nicola Group rocks are a stratigraphically complex sequence, at least 1800 feet thick, which have been subdivided into Basalt, Rhyolite, Carbonate and Clastic Sediment units. All the units strike and dip parallel to the margin of the Guichon Creek batholith and are within the batholith contact aureole. However, only the Clastic Sediment unit is in contact with the batholith.Most of the skarn and ore is within the Carbonate unit and more specifically within an Interbedded facies that consists of lime sandstone, lime siltstone, quartzo-feldspathic siltstone and argillite. The Interbedded facies and the adjacent barren Massive Limestonefacies are interpreted aspart ofa carbonate reef complex. The distribution of skarn and ore within the Interbedded facies suggests that the facies boundary was a physical and chemical barrier that resulted in concentration of metals adjacent to the Massive Limestone facies.Two stages of skarn formation have been recognized at Craigmont. In Stage I, ore-bearing magnetite-rich and actinolite-epidote-magnetite skarns developed both in basaltic rocks and in Fe-bearing siltstone and argillite of the Interbedded facies, while barren grossular garnet-epidote-calcite-pyrite skarns developed in Fe-poor rhyolitic bands within the Interbedded and Massive Limestone facies . In Stage ll, massive, barren grandite garnet skarn replaced mineralized Stage I skarns in the vicinity of diorite plugs. and specularite ore formed in brecciated Stage I skarn and clastic rocks away from the plugs. Theformation of Stage I skarns required no addition of material, only redistribution and concentration of elements already present within the Interbedded facies. However, the concentration of Cu in Stage lore requires a mechanism for more efficient leaching of Cu from the host rocks, an anomalous concentration of Cu at the site of the Stage I orebody or an additional input of Cu from an external source. The formation of Stage II skarn and ore requires only remobilization and recrystallization of Stage I skarn and ore.Copper and iron are the only elements in economic concentrations in the ore and chalcopyrite is the only significant copper-bearing mineral. Chalcopyrite is disseminated and interstitial to magnetite in Stage I mineralized skarns and is interstitial to specularite in the matrix of Stage II breccia ores. Chalcopyrite also occurs with pyrite as stringer ore in bleached • sediments and rhyolite tuffs in the stratigraphic footwall of the main orebodies.The Craigmont deposit has more features in common with Cu-Fe deposits hosted in metavolcanic and metasedimentary rocks than it has with typical skarn deposits associated with porphyry copper deposits. The orebody is more likely a product of concentration of metal contained within the Nicola Group rocks than of the mineralizing event that produced the . Highland Valley Cu-Mo porphyry deposits in the central part of the Guichon Creek batholith ."

Jan 1, 1980

By D. M. Rippley

THE St. Lawrence Seaway Project ranks with the greatest engineering undertakings of all time. A summary of major materials going into the construction of this project, shown in Table I, will assist in an appreciation -of this fact. These data relate to Seaway construction only, and it should be remembered that two large-scale power projects are in the construction stage on the St. Lawrence river concurrently with construction of the Seaway. A project of such magnitude as the Seaway would attract widespread interest even if it were being constructed in a remote area. The fact that it is located in a heavily populated and developed section of both Canada and the United States has done much to enhance this interest, and in many ways complicates the problems confronting the engineer in the design and construction phases. Many consider the St. Lawrence Seaway to be a new idea that has developed within the past decade - such is far from the fact, because the St. Lawrence River canal systems have existed for more than a century, and the Seaway Project is but a new, larger, and more efficient version of a continually expanding facility.

Jan 1, 1957

By O. A. Carson

"IntroductionTHE ZINC-BASE die casting alloys in common usage contain approximately 4 per cent aluminum as the major alloy element. In addition, they contain about 0.05 per cent Mg .and may• have a small amount .of copper. These are usually the only •elements intentionally present.Small amounts of some impurities have been shown to have a deleterious effect on the properties of these alloys and therefore the impurities are kept low by starting with '99.99%' zinc.The reasons for holding the aluminum content at 4 per cent are not clear. Some statements appear in the literature that higher aluminum increases the brittleness, but probably the chief reason was the relative price of zinc and of aluminum when 4% alloys became firmly established. At that time, aluminum was three to four times the price •of zinc on a weight •basis. Recent prices, roughly equivalent per lb., make aluminum considerably cheaper than zinc on a volume basis and suggest that increased aluminum content would result in a decrease in the cost per piece due to the lower density of the alloy.Little information could be found in the literature and, therefore, it was decided to determine some physical properties of the higher aluminum zinc-base alloys made from high-purity zinc."

Jan 1, 1953

By Matt Manson

Renard?1-10 kimberlite pipes and ?Lynx-Hibou?kimberlite dyke system within ?Foxtrot?property 50/50 JV with SOQUEM, Stornoway operator 2001: Discovery of the Renard kimberlite pipes 2003: Discovery of the Lynx-Hibou kimberlite dykes 2006-2007: Bulk sample program 2008: First 43-101 Resource and Preliminary Assessment 2009/2010: Updated 43-101 Resource

May 1, 2010

By B. Dubreuil, J. -M. Lalancette, D. Lemieux, C. Chouinard

The extraction of gold and silver has been examined via the use of mixed halogens: chlorine and bromine. The reaction was performed in a brine of sodium chloride with a small amount of sodium bromide at 40-50°C, in an atmosphere of chlorine, at atmospheric pressure. The process takes advantage of the very high reactivity of bromine towards gold, while the higher oxidation capacity of chlorine leads to gold chloride as end product with recycling of bromine. Fast reaction rates are observed along with gold recovery at the level of 95%. Chlorine-consuming common elements are removed prior to chlorination.

Jan 1, 2011

By P. E. Cavanagh

Introduction A comprehensive study of the economics of processes for smelting iron ores has been made by the Ontario Research Foundation on behalf of the Ontario Research Commission. This survey has included investigations of all processes in commercial use, and proposed processes which are still in the experimental stage. The two main objects of this work were to discover (l) whether any known processes would be particularly suited to present and future Canadian conditions, and (2) whether any new process would be of assistance in solving the present scrap shortage in Canada. The future prospects of the Canadian iron smelting industry have changed radically in the past ten years. For nearly twenty years before 1939 no iron ore was mined in Canada. The ore used was imported, mainly from the United States and Newfoundland. The economics of iron blast-furnace smelting always force the location of blast furnaces near the source of coal for making high-grade metallurgical coke, and near the market for iron and steel, rather than near the iron ore. Blast-furnace installations in Canada are confined to the north shores of the Great Lakes with ready access to United States coal and ore and the major Canadian markets, and to Nova Scotia near the coalfields of that Province. This distribution of primary smelting capacity naturally results in relatively high prices for iron and steel in the West, the North, and in Quebec.

Jan 1, 1948

By William Petruk

Image analysis studies were performed on mill products from pilot-plant and laboratory tests that had been conducted to determine the effect of grinding media on the selective flotation of two zinc-lead-copper ores. It was found that, when the ores had been ground to the same degree of fineness with flint pebbles, ceramic pebbles or ore fragments (autogenous grinding) as with steel balls, there generally was increased sphalerite, chalcopyrite and galena liberation in the flotation feeds, depending on the textures of the minerals. The increased sphalerite liberation fully accounted for the improved zinc recoveries that were obtained when steel balls were replaced by either pebbles or ore fragments. The increased chalcopyrite and galena liberation accounted for part of the changed technical efficiency of concentration, but other factors, probably changes in oxidation and reduction of iron and in consumption of oxygen, also contributed.

Jan 1, 1977