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By J. C. White

"During the early development of the Mattabi Mine in 1970, discussions with the Ontario Government revealed their policy of prohibiting, as much as possible, the development of new, isolated, single-industry townsites. Subsequently, Mattabi located its first housing in the Township of Ignace, which is situated 50 miles from the site of the mine and plant. Over 200 employees now commute 100 miles daily to and from work.This paper describes the experience gained and discusses the advantages and disadvantages of a remote townsite."

Jan 1, 1976

By W. J. Kuit

Since closure in 1968, the Wedge Mine, situated adjacent to the Nepisiguit River in New Brunswick, has been flooding with acidic water containing toxic levels of heavy metals. Cominco Ltd. has undertaken a series of pollution control measures to mitigate the threat posed to the river quality. Included has been a successful treatment campaign in 1976 which discharged in excess of 30 million gallons of high-quality effluent from the accumulated volume of mine water. The sources of contamination have been identified as actively leaching waste dumps. A comprehensive program of permanent corrective measures has been prepared which will culminate in mine backfilling. Once completed, the unacceptable burden of water treatment in perpetuity at a non-producing property will be removed.

Jan 1, 1977

By C E. Gordon Brown

Aircraft utilization, weather and cost data are given for three separate projects north of the sixtieth parallel in the Northwest Territories and the Yukon Territory. These operations, carried out by helicopter-equipped geological and prospecting parties, have cost $24 to $30 per square mile, depending principally on the distance from the base. They provide adequate surface exploration of areas with 40 to 50 per cent rock outcrop. A good one-inch-to-one-mile geological map can be made. T HE exploration of the Canadian northland has been given increasing attention by the mining industry during recent years. In many cases, the initial problem is to make an adequate reconnaissance of a large area where existing geological information is meagre. The Geological Survey of Canada pioneered the use of helicopter-equipped geological parties for mapping at a scale of eight miles to the inch.

Jan 1, 1964

By H. Ranjbar

The Darrehzar porphyry Cu deposit is situated in the Urumieh-Dokhtar magmatic suite of Central Iran. The REE and trace element data suggest that the deposit lies within a continental margin setting. Phyllic and propylitic alteration are pervasive in the area but potassic and argillicalteration are not readily recognized on the surface. This is possibly the result of super gene weathering of the surface rocks or because of an intense phyllic overprint. Poor soil development and abundant outcrop make the area suitable for a case study of lithogeochemical exploration technique for Cu deposits. A total of 262 rock samples was collected over the area and analyzed for 15 elements. The geochemical data cor-relate with the mineralogical composition of the rocks with the phyllic zone being marked by high-er concentrations of Si, Al, K, and by a high sericitization index while Ca, Mg, Sr, total Fe and Mn are more abundant in the propylitic zone. The lithogeochemical study indicates a metal zonation from a Cu + Mo-rich core to a Zn + Pb ± Ag-rich outer zone. Principal component analysis is useful for separating element associations, which in turn reflect the alteration halos. Principal components 1 and 2 depict alteration zoning, where-as 3 shows an association of Cu and Mo, that roughly defines the mineralized area.

Jan 1, 1997

By D. W. Hayley

The rapid expansion of exploration drilling with anticipated production facilities for oil and gas in the Mackenzie Delta region of the Northwest Territories has created a demand for granular construction materials. This paper discusses the technique adopted and experience gained by the authors from several major resource evaluation programs in this remote area. The first part of the paper describes a methodology for deposit identification, logistics of helicopter and ground-based drilling operations and the sampling difficulties which are unique to permafrost: soils. The second part describes the exploitation of a large glaciofluvial deposit at YaYa Lake on Richards Island. Granular construction material is sparse in the delta region relative to projected demand. Exploitable sources of granular materials for aggregates or construction borrow are found in glaciofluvial deposits of Pleistocene age or in outcrops of Paleozoic bedrock. Glaciofluvial landforms can be located by reference to published surficial geology maps coupled with airphoto interpretation. Preliminary assessment of these features in a large region is most economically carried out during the summer months with a drill that is transportable by helicopter. Once prospective borrow pit sites are identified, a detailed ground-based winter drilling program must be undertaken to establish aggregate quality and quantity, and to provide information on natural features which could affect development. The glaciofluvial terrain has been highly modified by the formation of massive ground ice within the gravel deposits. This presents some unique pit development problems which are not encountered in a normal bedrock quarry operation.

Jan 1, 1977

By A. Motamedi

Indoor localization has gained importance as it has the potential to improve various processes related to the lifecycle management of facilities and to deliver personalized and location-based services. Radio Frequency Identification (RFID) based systems, on the other hand, have been widely used in different applications in construction and maintenance. This paper investigates the usage of RFID technology for indoor localization of RFID equipped movable assets during the operation phase of facilities. The location-related data on RFID tags attached to fixed assets are extracted from a Building Information Model (BIM) and can provide context-aware information inside the building which can improve Facilities Management (FM) processes. The paper proposes a new approach to use received signals from available reference tags in the building attached to fixed assets to locate movable assets. The approach uses signal pattern matching and clustering algorithms for localization. As a result, a user equipped with an RFID reader is able to estimate the location of target assets, without having access to any Real- Time Location System (RTLS) infrastructure. A case study is performed to demonstrate the feasibility of proposed methods.

Aug 1, 2013

By J. W. Matousek

The heat content of the waste slag from a typical smelting operation methods for estimating the thermodynamic properties of smelting slags, to include: -- heats of formation -- heat capacities (specific heats) -- heat contents -- melting temperatures -- heats of fusion The techniques are illustrated with the analyses of a nickel reverberatory furnace slag from Copper Cliff, an iron-making blast furnace slag, and a "lateritic" slag from a ferronickel operation in Colombia.

Jan 1, 2007

By D. Emadi

The ASTM B108 Mould and a Modified Mould were used to cast test bars under a variety of conditions: mould and pouring temperatures, mould coating and tilt. Mechanical properties were determined in the as-cast and heat-treated conditions. The ASTM Mould is less sensitive to casting variables. Enlarging the gating system and adding additional gates to the ASTM mould can improve properties in the tilt position. The reproducibility of properties in as-cast and T6 heat treated bars was investigated.

Jan 1, 2004

By K. Thuro, L. Wilfing, H. Kasling

"In mechanized tunneling, performance prediction is a crucial issue for estimating excavation costs and construction time of a tunnel project. The aim of this work is to compare the calculated parameters by penetration prediction models with the results of penetration tests during excavation by a Tunnel Boring Machine (TBM) at actual tunnel projects. This comparison helps to improve the existing prediction models (Gehring, 1995 and Rostami (Colorado School of Mines), 1997.) and to develop a new, so-called “Alpine Model” (research group ABROCK; Schneider et al., 2012).On-site penetration tests are a common tool to determine performance of a TBM in certain geological environments. During a test, the TBM is operated under defined conditions that allow comparing the results of different projects and machine types. There are two different types of penetration tests in use. The more common type, described by Bruland (1998a), is based on test drives at different thrust levels. The tests in this study are performed as start-stop-tests, meaning that the TBM starts from zero to the maximum possible thrust and reverse with slowly increasing respectively decreasing steps (Frenzel et al., 2012). To gain information about the interaction between TBM and rock mass, a detailed geological documentation including an analysis of the discontinuity pattern and laboratory testing for rock strength characterization are mandatory.Within the last year 16 penetration tests have been performed. The results are thrust- penetration curves (Figure 2) showing that up to a certain penetration rate only crushing occurs (subcritical penetration). From there the desired rock fragmentation process called chipping takes place (Frenzel et al., 2012). These two different fragmentation processes can be described best by a bilinear function as seen in Figure 3. Both, CSM- and Gehring-model, do not fit to the trend of the penetration rates determined during the excavation process as they are using potential or simple linear functions.Another parameter that has to be implemented into the new prediction model is the influence of discontinuities. In case of favorable orientation and spacing, discontinuities reduce the required thrust at same penetration rates. In contrast, unfavorable discontinuity systems can cause blocky faces and hence worse performance than predicted. Besides discontinuities, the toughness of rocks has to be taken into account when predicting the penetration as tough rocks need more energy to obtain complete failure than brittle rocks.Key advantage of these tests in comparison to existing are more data points in less time. By improving respectively extending the existing penetration prediction models with the stated parameters, the penetration prediction for TBMs can be more accurate and also wear calculation can benefit from this approach."

Jan 1, 2015

By J. Olson

"A model was developed to use near-infrared (NIR) analysis of pulverized ore samples to estimate the recoverable gold content for ores from the Barrick Cortez Hills underground mine. Current routing practices use a ratio of the cyanide soluble gold content and fire assayed gold (CN/FA) to classify ores as oxide or refractory. Prediction accuracy of the NIR model was equivalent to the CN/FA ratio. Prediction accuracy was improved by combining the CN/FA ratio and the NIR spectra. Bootstrap validation estimates the root-mean-square error to be 9.92% with an estimated r-squared value of 0.893. This model will allow more accurate estimates of the variability in recoverable gold content throughout this mine. These data will aid in building an improved geo-metallurgical model or in making better informed routing decisions during the production cycle.INTRODUCTION The contained gold of an ore available for cyanidation is often related to subtle variations in the mineralogy. It is difficult and expensive to collect enough mineralogical information in order to predict how the variable mineralogy will impact the metallurgical results and project economics throughout the life of the mine or mill. Near-infrared spectroscopy may be an effective tool to rapidly and inexpensively collect discrete, quantitative mineralogical data for minerals that contain transition metal oxides, metal sulfides with semi-conduction properties, rare earth metals, and some chemical groups having di-pole covalent bonds such as carbonates, sulfates, and various types of clays (Hunt, 1977). Near-infrared spectroscopy can be a powerful tool for geo-metallurgical characterization of deposits where the presence of these minerals has direct or indirect relationships to metallurgical results such as grindability, regent consumption, or recovery. Near infrared spectroscopy is a rapid analysis that measures the intensity of reflected light in the near-infrared spectrum. The ranges for the ASD-Panalytical units used in this study extend through the visible spectrum and into part of the UV spectrum, reporting reflection by wavelength from between 350 nm to 2500 nm. Absorption peaks visible in this range are a result of interactions with outer valence elections or chemical bonds. The location and intensity of the peaks vary depending on the chemical composition and crystal structure of a solid indicating the presence and abundance certain minerals (Hunt, 1977; Clark, 1984)."

Jan 1, 2017

By M. Kunst

The creep behavior of three AJ62 alloys was investigated in a wide range of stresses and temperatures. Multi-level tensile creep tests revealed a distinct primary creep stage and a high stress exponent up to a value of 10. The threshold stress concept which is commonly used in combination with high stress exponents was utilized in the analysis of creep behaviour. This resulted in an effective stress exponent for the AJ alloys indi¬cating dislocation climb as the dominating creep mechanism. In addition, microstructural observations of the lamellar eutectic and of the a-Mg-matrix were carried out using opti¬cal microscopy, SEM and TEM. The creep properties of the alloys are discussed in the context of microstructural parameters such as phase volume-fraction, stability and solute supersaturation.

Jan 1, 2006

By K. Muehlenbachs, J. U. Stemler

"Abstract - The Boston deposit is a recently discovered Archean lode-gold deposit located approximately 700 km northeast of Yellowknife, in the southern portion of the Hope Bay volcanic belt. Primary H2O-CO2-NaCl fluid inclusions associated with gold mineralization at Boston are of low salinity (4.6 ± 1.4 eq. wt.% NaCl, n = 182) and contain pure CO2. Homogenization temperatures of liquid-phase inclusions average 270° ± 33°C (n = 141), but some fluid inclusion assemblages contain coexisting liquid- and vapor-phase inclusions that homogenize near critical conditions, suggesting phase separation. In these groups, liquid-phase inclusions homogenized at 299° ± 25°C (n = 24), and vapor-phase inclusions homogenized at 338° ± 28°C (n = 18). These temperatures overlap within error, and a median temperature of ~320°C is taken as representative of trapping conditions within the veins. An approximate pressure of 2-3 kbar was estimated from fluid inclusion isochores at this temperature. Stable isotopic compositions of carbonate minerals from the mineralized zones range from -4.7‰ to -3.1‰ in d13C, and from 11.2‰ to 12.8‰ in d18O; quartz ranges from d18O = 12.8‰ to 14.9‰; and pyrite ranges from d34S = 2.1‰ to 3.5‰. The d18OH2O, d13CCO2, and d34SH2S values of the fluid calculated from these minerals at 320°C are 6‰-9‰, -2.4‰ ± 0.6‰, and 1.5‰ ± 0.5‰, respectively, and are intermediate between metamorphic and magmatic compositions. A unique source for the fluids cannot, therefore, be constrained from these data. Petrographic and geochemical data for the Boston deposit are consistent with data from other Archean lode-gold deposits worldwide, implying that the Boston deposit formed in a similar environment and from similar types of fluids. These results suggest that the Hope Bay volcanic belt may represent a major new mesothermal gold belt in this part of Nunavut. Sommaire - Le gîte Boston a été récemment découvert à environ 700 km au nord-est de Yellowknife dans la partie sud de la ceinture volcanique de Hope Bay, il s’agit d’un gîte d’or filonien d’âge Archéen. Les inclusions fluides primaires de H2O-CO2-NaCl associées à la minéralisation aurifère du gîte Boston présentent une faible salinité (4.6 ± 1.4 eq. pds.% NaCl, n = 182) et contiennent du CO2 pur. La température d’homogénéisation des inclusions à phase liquide est en moyenne de 270° ± 33°C (n = 141), mais certains assemblages d’inclusions contiennent des phases liquides et gazeuses coexistantes qui s’homogénéisent dans des conditions quasi critiques, suggérant qu’elles résultent d’une séparation de phase. Dans ces groupes, les inclusions de phase liquide s’homogénéisent à 299° ± 25°C (n = 24) et les inclusions de phase gazeuse s’homogénéisent à 338° ± 28°C (n = 18). Ces températures se recoupent à l’intérieur des limites de l'erreur de mesure, et nous considérons qu’une température médiane de ~320°C est représentative des conditions de piégeage dans ces veines. Les isochores permettent d’estimer une pression d’environ 2-3 kbar à cette température. La composition des isotopes stables des carbonates dans les zones minéralisées s’étend de -4.7‰ to -3.1‰ pour d13C et pour de 11.2‰ à 12.8‰ pour d18O; les valeurs de d18O pour le quartz varient de 12.8‰ à 14.9; et les valeurs de d34S dans la pyrite vont de 2.1‰ à 3.5‰. Les valeurs de d18OH2O, d13CCO2, et d34SH2S du fluide calculé à partir de ces minéraux à une température de 320°C est de 6-9‰, -2.4‰ ± 0.6‰, et 1.5‰ ± 0.5‰ respectivement, reflétant des conditions intermédiaires entre des compositions métamorphiques et magmatiques. Il n’est donc pas possible d’identifier une source unique pour ces fluides à partir de ces données. Les données pétrographiques et géochimiques du gîte Boston sont similaires à celles d’autres gîtes d’or filoniens ailleurs dans le monde, ce qui implique que le gîte Boston s’est formé dans un environnement similaire à partir des mêmes types de fluides. Ces résultats suggèrent que la ceinture volcanique de Hope"

Jan 1, 2006

By K. Mayhew, R. Bruce, A. Heidel, G. P. Demopoulos

"Teck and Aurubis are working together to commercialize a technology for the processing of copper arsenic sulphide concentrates that is economic and sustainable with regards to the environment and community. The pressure hydrometallurgical approach is a desirable option as mineral extraction and arsenic fixation can take place in a single autoclave vessel. A test work program was carried out where a range of copper concentrates with varying arsenic grades was processed under CESL leach conditions. This paper discusses the stability character (in terms of arsenic) of the resulting residues and their mineralogy. The basic ferric arsenate sulphate phase (BFAS; otherwise known as type 2) was identified as the main arsenic carrier. All CESL residues demonstrated high stability (<1 mg/L As) through a range of aggressive (pH and ORP) environmental leach conditions.INTRODUCTIONArsenic deportment and control in the copper industry needs an integrated approach involving each stage of the value chain, i.e. exploration, mine operation, refining process and mine closure. Teck Resources Limited (Teck), Canada’s largest diversified mining company and Aurubis, Europe’s largest copper producer, have formed a partnership to advance the application of CESL copper-gold technology for the development of high arsenic bearing copper resources (Bruce et al., 2011).Among the options for arsenic control in the metallurgical treatment of copper concentrates is the precipitation of ferric arsenate, which is widely accepted as the most suitable method for stabilizing arsenic (Ferron and Wang, 2003). The pressure hydrometallurgical approach to processing arsenic bearing copper concentrates is a favorable option as mineral extraction and arsenic fixation can take place in a single autoclave vessel. Under CESL pressure leaching conditions (150 °C, 1380 kPa) high copper extraction and arsenic (V) fixation is possible.Within the pressure leach autoclave, arsenate and ferric iron react to form scorodite type phases. The precipitate formed under CESL conditions is dependent on the Fe (III) /As (V) ratio and the tenor of cations and anions, particularly excess sulphate (Gomez et al., 2011a). Previous studies on CESL residues have found arsenic to be present as crystalline scorodite (FeAsO4.2H2O) (Bruce et al., 2011), basic ferric arsenate sulphate (BFAS: Fe(AsO4)1-x(SO4)x(OH)x·(1-x)H2O, where 0.3<x<0.7), and/or arsenate adsorbed on to hematite (Gomez et al. 2011b). Although not a focus of previous work, scorodite was the predominant precipitate formed when the concentrate Fe/As was <1.5 (Mayhew et al., 2010), and BFAS was the predominant precipitate when the concentrate Fe/As was >10 (Gomez et al. 2011b)."

Jan 1, 2012

By L. H. Van Loon

INTRODUCTION THE property of Madsen Red Lake Gold Mines, Limited lies between Russet and Faulkenham lakes in Baird and Heyson townships, district of Patricia, Ontario. It is about six miles south west of the town of Red Lake, with which it is connected by an all-weather road. All orebodies found to date at the property are silicified lenticular bodies which lie within tuff beds. The ore bas a specific gravity of 2.95. It consists of mica and chlorite schist, silicified and containing a considerable amount of disseminated carbonate, and mineralized with pyrite, pyrrhotite, magnetite, arsenopyrite, and chalcopyrite. Of these, pyrite, in coarse to fine disseminated grains, is by far the most abundant. Pyrrhotite occurs in ?the gangue material as medium to fine disseminated grains. A very small amount of arsenopyrite, in small crystals, is associated with the pyrite, and small grains of chalcopyrite occur in both gangue and pyrite. Although some of the gold present in the ore is quite coarse, a good deal of it is extremely fine.

Jan 1, 1951

By L. Van Wyk, J. Fernandez, J. Suarez, L. J. Diaz, A. Uria, D. Breeuwer

"Ventilation is an essential component of any underground mine, playing a vital role in ensuring the health and safety of workers, and a mine’s continuous operation. At a time when mining companies are increasingly having to move to deeper underground operations in pursuit of high-grade ore-bodies, the search is on for more efficient ventilation systems that will allow mining to be carried out at even deeper levels whilst ensuring the protection of workers and the maximisation of productivity through temperature management and the lowering of energy costs. Mining companies today are looking for innovative ways to deliver new technologies and procedures to enhance their mine’s profitability. Energy consumption by mine ventilation systems is higher than ever due to stringent specifications of underground equipment (primarily combustion engine emissions), air quality standards and mining at deeper levels which all require more powerful ventilation systems. With energy costs associated with operating ventilation systems being a mine’s second-highest cost of production after labour, finding the optimal ventilation solution is critical to a mine’s performance. Proper fan design remains a major factor in reducing capital expenditures (CAPEX) and operational expenditures (OPEX), which means that there are compelling reasons for making use of comprehensive factory testing at full power before fans are dispatched to site to simulate the mine’s current and future design requirements, and thus verify the fan’s effectiveness in ‘real’ conditions.INTRODUCTION A primary mine fan is considered the heartbeat of the entire mine ventilation system, drawing fresh air from the surface and providing a safe environment for miners. A ventilation system’s lack of performance often leads to a reduction in acceptable air quality levels for underground working operations and can potentially have an adverse impact on production rates."

Jan 1, 2019

By M. Kuyumcu

After German reunification the mining industry in former East Germany was profoundly restructured. Beside privatization of profitable companies the public sector took over responsibility for the mining operations to be shut down. Therefore state-owned companies cope with technical, ecological, and social challenges. The rehabilitation and reclamation has to rededicate former mining areas to new use and provided new jobs as well. In the lignite mining districts there are around 100,000 ha of mining area, a mining caused disturbance to the groundwater balance and to the system of surface water bodies of approx. 390,000 ha. They are called the largest landscape construction site in Europe. In addition to the results and diverse experience achieved over the past 23 years, a description will follow of our new challenges and of an outlook on remaining tasks. This article will describe the financing, as well as aspects of the jobcreation policy arising from lignite industry remediation.

Aug 1, 2013

By P. Babak, E. Insalaco, O. Babak, P. Henriquel

"Detection of outliers is an important primary step in geomodelling. Geological datasets often contain errors due to problems such as measurement device limitations and recording glitches. In this paper, a robust Mahalanobis distance–based approach is successfully applied to particle size distributions of the Joslyn lease, an oil sands development site near Fort McMurray, Alberta, Canada. Automatic outlier detection and geological review were combined. Outliers from the Mahalanobis distance approach were compared with their respective core photographs to determine if laboratory measurements and facies classification were correct. A checking procedure for laboratory technicians is proposed.RÉSUMÉ La détection des valeurs aberrantes constitue une étape primaire importante de la modélisation géologique. Les ensembles de données géologiques contiennent souvent des erreurs en raison de problèmes tels que les limitations des instruments de mesure et des pépins d’enregistrement. Dans le présent article, une méthode robuste basée sur la distance de Mahalanobis a été mise en oeuvre avec succès aux granulométries du bail minier Joslyn, un site de sables bitumineux en développement à proximité de Fort McMurray, Alberta, Canada. La détection automatique des valeurs aberrantes a été combinée à une étude géologique. Les valeurs aberrantes de la méthode de la distance de Manalanobis ont été comparées avec leurs photographies respectives de carottes de forage afin de déterminer si les mesures en laboratoire et la classification des faciès étaient correctes. Une procédure de vérification pour les techniciens de laboratoire est proposée."

Jan 1, 2015

By Claude A. Jr. Seger

Introduction This paper presents in detailed form the results of settling tests that were published in a few preliminary notes in the April 1949 issue of the Bulletin (p. 166). Carborel is the trade name for sodium carboxymethyl-cellulose and aluminium carboxymethyl-cellulose produced by the reaction of monochloroacetic acid on the alkali cellulose to form an ether. The water-soluble sodium carboxymethyl-cellulose has been known in Europe for several years as sodium cellulose glycolate and has been marketed under several trade names. These cellulose ethers, however, are relatively new in North America, where the name carboxymethyl-cellulose is often abbreviated to C.M.C., or they are referred to as cellulose gum. The particular grade of Carboxel used in the settling tests in the mill of Chesterville Mines, Limited, is the high-viscosity sodium carboxymethyl- cellulose known as Carboxel H.V. It is a white, fluffy powder and is hygroscopic, although not deliquescent. Carboxel solutions in water are colourless, odourless, and resistant to beat and light. They are stable to alkalies, but are precipitated by acids when the pH is reduced below 4.0, and also by solutions of soluble lead, iron, copper, aluminium, and chromium salts. Solutions of Carboxel exhibit the properties of hydrophilic colloids.

Jan 1, 1949

"Acid resistant brick lined autoclaves and related vessels are utilized in pressure oxidation for the recovery of gold, copper, and other metals. The combination of the corrosion resistant membrane, acid resistant brick, mortar and steel shell is a composite system that requires a sophisticated stress analysis. In order to obtain meaningful results both the model and physical properties of the materials must be carefully selected. Evaluation of the calculated results requires an understanding of both the failure mechanisms of ceramics and experience with the performance of existing lining systems.INTRODUCTIONAcid brick lining systems are used in pressure oxidation autoclaves and related vessels to provide thermal and mechanical protection for corrosion resistant membranes that are applied directly to the interior of the vessel shell. The acid brick and mortar must be resistant to the process conditions and must provide a mechanically reliable structure.The construction of lined vessels incorporates a wide range of materials that can include the carbon steel vessel, austenitic weld overlay, lead lining, organic membrane, ceramic brick, mortars and other alloy components. The physical properties of the materials can vary by orders of magnitude and when combined in the construction of the lined vessel create a complex composite structure. The materials may be bonded together or act independently of each other. Stresses are induced into the lined vessel include pressure, thermal expansion, chemical expansion and mechanical loads.The complexity of these systems makes it is very difficult to account for all of the variables in the structural analysis of lined vessels. Historically calculations were simplified and designers primarily relied on experience with previous applications.The greatly improved tools for Finite Element Analysis (FEA) available today allow for detailed calculation of the stresses imposed on the vessel shell and lining. Koning & Lauzon (2004) presented a paper on design fundamentals including a discussion on the application of FEA methods at Pressure Hydrometallurgy 2004 in Banff. When a designer carefully constructs a model and selects the correct materials properties for the calculations, meaningful and useful results can be achieved."

Jan 1, 2012

By H. E. Pawson

Giant Yellowknife is located 600 air miles north of Edmonton on the north shore of Great Slave Lake in the Northwest Territories. In its 24 years of operation some 7,730,000 tons of ore have been treated to yield $175,000,000 worth of gold.The gold ore occurs at irregular intervals throughout a fold-like sericite schist zone cutting Precambrian rocks. The ore is characterized by 40 to 80% quartz - carbonate and about 10% pyrite and arsenopyrite. Considerable amounts of stibnite and antimony sulpho-salts are also present. Gold is finely divided in the native state existing in complex association with the sulphides. In most instances stibnite is barren but minor values are evident on occasion. Visible native Fold, quite prevalent in the early operating years, is, practically non-existent today. It was readily apparent from mineral dressing investigations conducted in .1944 that Giant ore would be difficult to treat. By 1948 a flow sheet had been established and operations began. In the ensuing years, changing ore characteristics necessitated modifications to some process steps and complete abandonment of others. By 1962 the major metallurgical problems were solved and all that remained was the refining of operating performance to its highest level.With one or two exceptions today's operation follows the practice established by 1962 (Fig. 1 - Flowsheet).

Jan 1, 1973