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By Deni Côte, Michel Dagbert, Marcel Vallée

"Greater reliability of mineral deposit and reserve estimates can be attained through better quality control of the data and information acquisition, and the estimation processes. This paper reviews the following key requirements:1. greater awareness of the significant figures of both data and estimates, and better understanding of the probabilistic aspects of the estimates, their confidence limits and margins of error;2. greater reliability of the information that supports the estimates, by more explicit and more rigorous methods and standards for data acquisition and for interpretations;3. more quantitative estimations of geological/mineral continuity, based on improved three dimensional sampling patterns and the use of geostatistics; and 4. better integration at the project engineering and mine production stages, of the mineral deposit characteristics and mining method constraints, for more efficient mineral recovery and mine quality control.RÉSUMÉUne plus grande fiabilité des estimations des gisements et des réserves minières requiert plus d'emphase sur le contrôle de la qualité de I ‘acquisition de l'information et du processus d'estimation. Les exigences suivantes sont revues:1. le respect du niveau d'exactitude des données et des estimes en n'utilisant que le nombre approprie de chiffres significatifs des observations et mesures, et en exprimant le niveau de confiance et la marge d'erreur des estimations;2. l'amélioration de fa fiabilité des données par des normes plus rigoureuses pour leur acquisition et leur vérification, et par des méthodes plus systématiques d'interprétation et de modélisation;3. l'estimation plus rigoureuse de la continuité des minéralisations dans les trois dimensions des gisements, par des patrons échantillonnages mieux adaptes awe paramètres géologiquement minéralogiques, et par l'utilisation des méthodes géostatistiques; et4. l'intégration plus poussée, particulièrement lors de la planification de l'exploitation minière, des caractéristiques des gisements avec les contraintes des méthodes d'exploitation, pour améliorer la récupération et le contrôle de la qualité en exploitation."

Jan 1, 1993

By Jared Onyirimba, Jim Viellenave, Hal Demuth, Dale Verran, Chad Sorba, Errol Lawrence, David Bronkhorst

As outlined within the Denison Mines Corp’s (“Denison”) Pre-Feasibility Study ("PFS") completed in late 2018, additional work is required to increase confidence and reduce risk associated with the application of the In-Situ Recovery (“ISR”) mining method at the Phoenix deposit, located on the Wheeler River Uranium Project (“Wheeler River” or the “Project”) in northern Saskatchewan. The successful application of ISR in any geological environment largely hinges on three fundamental requirements, 1) permeability (of the deposit), 2) containment (of the mining solution) and 3) leachability (of the mineralization). Denison has designed several staged technical programs to progressively reduce risk associated with these requirements as the Company advances the Project toward a Feasibility Study (“FS”) and Environmental Impact Assessment (“EIA”). This paper will discuss the scope and results of certain technical programs being undertaken as the Company aims to develop the first ISR mining operation in the Athabasca Basin.

Jan 1, 2020

?Introduction to the Delphi Group ?Why is carbon important to your organization ?Key elements of a carbon management strategy ?Inventory ?Risk & opportunity scan ?Mitigation options and financial mechanisms ?Identify targets and develop policy ?Communication and improvement ?Manage for success

May 1, 2009

By A. Chieregato, C. G. Oñate Salazar, D. Martinelli, D. Peila, M. Barbero

This paper is aimed to confirm the possibility to excavate fractured rock masses by using EPB shields, even in presence of relevant water tables. This verification is based on laboratory test experiences carried out at TUSC laboratory of Politecnico di Torino, where the natural material is tested in order to verify the suitability of a certain conditioning technique in particular conditions. This is due to the fact that every case should be studied apart from existing studies on a certain rock type, as other factors such as fragmentation of the rock mass, natural water content and porosity of the rock can considerably influence the final result of the conditioning process. The most important aspects that allow to consider the conditioning of fractured rock masses as suitable are: possibility to create a plastic paste that can transmit the pressure at the front in a effective way; reduce the permeability of the spoil material in order to reduce the possibility of water leakage inside the chamber and eventually in the tunnel; verify the consistency of the conditioned material for the extraction through the screw conveyors and the belt conveyors. For this research an argillitic schistose rock mass, with some quartzitic and calcareous inclusions, has been studied by using different level of conditioning in order to verify the suitability of an eventual EPB excavation through this formation.

Jan 1, 2015

By M. J. Dry, G. B. Harris

"This paper presents basic chemistry and operating conditions for the hydrolysis of ferric chloride into solid hematite and gaseous hydrogen chloride, and shows how this unit operation can be applied in chloride hydrometallurgy to regenerate strong hydrochloric acid and reject iron without also rejecting valuable metals such as nickel, copper and cobalt. Two examples are used to illustrate the hydrolysis technology and compare it to existing technology. The first is the regeneration of spent steel pickling acid, comparing hydrolysis to conventional pyrohydrolysis. The second example is the processing of a hypothetical low grade nickel laterite, comparing the novel chloride hydrolysis route to conventional sulphate HPAL technology.INTRODUCTION Whilst, in many respects, the control and removal of dissolved iron from chloride leach solutions can resemble the manner in which it is done in sulphate systems, chloride chemistry additionally offers the ability to achieve the same objectives in different ways (Harris, 2014). Conventionally, iron is oxidised to its ferric state (if necessary) and then precipitated with a base, usually magnesia where the feed is a laterite and lime where it is a sulphide, since calcium will precipitate sulphate formed during leaching. One method for controlling iron is to form FeOOH, either ß-FeOOH (akaganéite), a-FeOOH (goethite), or a mixture thereof (Fillipou and Choi, 2002). However, if akaganéite is formed, the precipitate will contain a significant chloride component (as high as 7% Cl), leading to chloride losses and difficulty in satisfactorily disposing of the residue. Washing chloride from akaganéite is almost impossible due to the propensity of the solids to undergo peptization. The conventional approach requires the addition of a base, but it is based to some extent on controlled supersaturation precipitation (Demopoulos, 2009), which produces a more uniform and crystalline material and is far more attractive than, for example, the turboaeration process proposed by Great Central Mines in their chloride copper process (Raudsepp & Beattie, 1986)."

Jan 1, 2016

By E. M. De Souza, P. Lausch, D. O. DeGagné, J. F. Archibald

"The potential use of industrial and municipal waste glass as a partial pozzolanic replacement for Normal Portland cement in mine backfill has been investigated. Considerable quantities of glass are currently discarded into landfill sites at high cost to municipal and industrial users with no foreseeable environmental benefits being gained by such disposal. This research study was undertaken to assess the viability of using ground waste glass materials as partial binder replacement of Portland cement fractionswithin consolidated mine backfill materials. The program was implemented to review various factors that could influence successful incorporation of glass waste replacement of cement, these factors being the feasibility of glass waste procurement, determination of process economics and the physical and chemical suitability of ground waste glass materials to generate adequate backfill strength when replacing Normal Portland cement fractions. A series of laboratory assessment trials were established to evaluate backfill component characteristics and mixture strength properties for both standard Portland cement-consolidated and blended Portland cement/ground waste glass-consolidated backfill materials. Side-by-side review of the strength behaviour of various component backfill/cement mixtures was designed to permit comparative evaluation of the capabilities of ground waste glass and Portland cement products as backfill consolidating agents"

Jan 1, 1995

By J. Duriez, L. Scholtès, F. V. Donzé

"Fracture propagation process in brittle rock is investigated by means of numerical simulations performed with an adapted formulation of the discrete element method. The progressive failure mechanism is simulated through the breaking of the bonds making up the cohesion between the elements constituting the simulated medium. The use of appropriate contact laws associated to a near neighbor interaction feature provide the model the ability to reproduce fundamental characteristics of brittle rock behavior such as, for example, high values of the tensile to compressive strength ratio. Great attention is given to accurately describe the properties of the pre-existing joints or faults in the model. A specific joint model gives the possibility to define a tailor-made behavior of the discontinuity surfaces without suffering from discretization bias.Compression test simulations are performed on pre-flawed samples and compared to experimental results in order to validate the numerical approach for describing the initiation and propagation of fractures in brittle rock under mode I+II loading. It is shown that the crack mechanical parameters can greatly influence the fracturing pattern, in particular its frictional properties. Overall, the numerical simulations reproduce fairly well the failure patterns that are obtained experimentally.The discrete model is then used to study mode I+III loading to give an insight into fracturing problems occurring at the scale of the continental crust. The ability of the model to support mechanically the physical modelings performed with wet clay or sandbox is shown. As an example, the model is used to track the development of a twist crack system (wrench fault) through the nucleation and coalescence of microcracks."

Jan 1, 2015

By Masaru Kato

The plated gold being used by the electronics industry can be broadly classified into two categories: soft gold and hard gold. Soft gold is used for circuit metallization and for bonding semiconductor chips, while hard gold is indispensable as the contact material on electrical connectors, electromechanical relays, and printed circuit boards. The traditional baths from which to plate soft gold as well as hard gold contain the cyanide complex, [Au(CN)2]-, as the source of gold, which liberates free cyanide ions during the plating. The free cyanide is not only highly toxic but also attacks photoresists used to delineate circuit patterns and bonding pads. For these reasons, non-cyanide baths are in use to plate soft gold, whereas hard gold can be plated only from cyanide baths at present. In this presentation, the current status of both electrolytic and electroless non-cyanide processes for plating soft gold will be reviewed.

Oct 1, 2003

By P. C. Garg

"IntroductionThe Central Mine Planning and Design Institute (CMPDI) of India, started planning the extraction of thick seams highly susceptible to heating in 1977by the French method of sub-level caving and/or multi-slicing. Nitrogen flushing was proposed for inhibition of heating by the author in one such project - the Kotadih colliery.Inhibition of heating was unheard of in the Indian coal industry before 1977-78. The usual practice was to seal off a district or a part of the mine or the entire mine when spontaneous heating occurred. With very little equipment in a normal bord and pillar district and a low production rate, the financial loss in capital assets and in production did not warrant any serious thought for inhibition of spontaneous combustion. With the planned advent of longwall mining, particularly sub-level caving, with heavy capital investment as well as high production potential, the sealing of a longwall face due to spontaneous heating could not be considered an appropriate solution.Principle of Inhibition of SpontaneousCombustionFrench engineers have established that a fire will not break out when oxygen is 15% or lower in the general body of the air. However, once a fire starts, the percentage of oxygen has to be reduced to 2% - 4% to extinguish it. It is this principle which has been used at Blanzy Coalfield in France to inhibit heating and it is claimed that this has retrieved the integral sub level method of mining. Nitrogen infusion has been used in Frence since 1978 to keep the oxygen content below 14% in the goaf."

Jan 1, 1987

By T. B. Williams

Most geologists have felt the need of a longer base than is ordinarily available when using a Brunton compass or other convenient instrument for taking strikes and dips in the field. To overcome this difficulty a lath or stick with straight parallel sides is frequently used. This accessory adds to the accuracy of the work, but it is a decidedly inconvenient one for the geologist to carry, especially if he be heavily loaded or is travelling on horse-back or through thick brush on foot. The writer has abandoned its use in favour of a sturdy two-foot carpenter's rule. The rule preferred is manufactured by J. Rabone and Sons, Birmingham, England. It is provided with a good level-bubble set in one of the limbs, and a scale, of the protractor type, graduated to five degrees through 180 degrees, attached to the main joint at the middle of the rule. (See Figure 1). For an instrument of its kind it is very accurate, and, in addition to the uses mentioned below, it 'is a handy thing to have around any camp. It is frequently used when plotting roughly in the field and for a protractor when one is not available. When not in use it may readily be carried in the top of the high-boot or legging. Ordinary strikes are measured as illustrated in Figure 1, the compass being held against the rule, which is in a horizontal position. Dips may be measured in a corresponding way by holding the Brunton compass against the extended rule, which is thus used merely as a straight edge. It is usually much more convenient, however, to ? use the rule only for this purpose, in which case one foot of the length rests as a straight-edge against the rock surface. This adaption is shown in Figure 2.

Jan 1, 1929

By T. Yameogo

Many ideas, tools, technologies, and methodologies are believed to have staked their claims on the future of mining. For example, automation is strongly positioned as the platform within which mining will be practiced. A subset of automation ? intelligent mining ? will add some smart interactions between machines, technologies, the rock, and the environment. The future also calls for an improved approach to sustainability and corporate social responsibility. Mines of the future are dreamed of to be more ethical and more balanced. They will boast optimized designs, integrated value and supply chains, produce less waste, recycle and reuse, and will require less energy to operate. Then, what about the people that will operate this optimized ecosystem? How is the education system teaching the operators of the mines of the future? What kind of a future should mining education foresee to prepare the workers appropriately? In recent years, the shortage of skilled labor for mines around the world has created a tough competition to attract, retain, and train the very people without whom mining will cease to exist. In Australia, Canada, and the United States in particular, the war for talent has resulted in higher-than-usual labour costs. Such costs have dented the unit costs of many mining businesses. Concomitantly, mining contractors? and consultants? prices have increased to reflect the escalation of labour costs across the value chain. From labourers to engineers, from juniors to seasoned professionals, the increase in compensation is unprecedented. Yet, the shortage is still hurting the industry, and the high calibre candidates continue to be rare gems. The industry has been implementing aggressive solutions that include the increased hiring of skilled immigrants, the training and recruitment of minorities, and the retaining of near-retirement experienced employees. Public relation campaigns about the benefits of embracing careers in mining are also common. The CIM has also devoted a ?M4S? section to its pan-Canada meetings to educate the public, especially the youth, about the importance of the mining industry for Canada. Moreover, mining associations and universities are enticing students? enrolment through scholarships and financial support. Still, the balance between quantity and quality of workers can be discussed. This paper intends to discuss the present state of mining education as an essential part of the future of mining. The authors brush the picture of the education of miners, technicians, and engineers, against the backdrop of the technology-advanced mines of the future.

Aug 1, 2013

By Wei Ye, Lei Li, Xianjian Guo, Feng He

The purpose of the paper is to study the smelting process of copper concentrate with high Cu/S ratio produced in Africa or other areas around the world and theoretically analyze the influence of slag type on the smelting process. The paper has compared the processes used successfully in smelters, including CAPEX and OPEX and other factors, to provide reference for the industry to select the best process under specific conditions. INTRODUCTION At present, a great amount of copper concentrates with high Cu/S ratio, with chalcocite being the major source of copper, have been produced or are about to be produced in the Copperbelt in Africa and other countries in the world. The copper concentrate is usually high in copper (~30–55wt.%) and low in sulfur (~10–15wt.%). The conventional processes of smelting-converting and roasting-leaching-electro-winning for treating this type of concentrate is high energy and materials consumption such as electric power\fuels\flux et al. The direct-to-blister (one-step) smelting process can be considered favorable due to a reduction in processing steps. Up to now, there are four copper smelters in the world operating with the direct-to-blister smelting process. There certainly are problems in the process such as high copper content in the slag, strict operation requirement of slag cleaning electric furnace, etc. Except technical issues, the impact of factors on economical aspect such as power and material cost needs to be considered comprehensively in process selection. In this paper the technical issues of direct-to-blister smelting process, including slag treatment process, were analyzed and the comparison to the conventional processes and economic analysis of direct- to-blister smelting process to treat high Cu/S ratio concentrate were done.

Jan 1, 2019

By Timothy D. Dreger

In the spring of 2009, Suncor Energy Inc. technical personnel saw an opportunity to improve planning 0and mining of overburden material in order to address aggressive construction goals and increased mining complexity. By tying together current and historical equipment performance, geological model information, and material observation in the field new operating elevations for the shovels were developed. At the same time, methodology of recording and reporting overburden movement through the Modular Mining DISPATCH system was changed. The result of this first stage of improvements was an increase in construction-grade material available at the face. The personnel involved realized that other opportunities were available to build on the initial successes and establish processes that would stand up to attrition and experience levels. A cross-functional technical team was assembled to identify ways of further improving workflows around overburden mining. Some of the opportunities realized include greater alignment between planning, reporting and operations as well as development of reporting tools that help steward Mine Operations to the plan. All of which have resulted in Suncor meeting or beating its forecast overburden targets. The cross-functional technical team continues to seek out new and better ways of doing business so Suncor can continue to deliver on its commitment of outstanding performance and results.

May 1, 2011

By Y. Kocaefe, D. Bhattacharyay, D. Kocaefe

The carbon anodes used in the electrolytic production of aluminum are made of petroleum coke, recycled anodes and butts, and coal tar pitch. Due to technological advances in the aluminum production technology, aimed at increasing production and decreasing energy consumption and greenhouse gas emissions, better quality anodes are required. Presently, the anode quality is evaluated by visual inspection and the analysis of a small core taken from 1.5-2% of the anodes produced. The visual inspection is susceptible to human error and limited to surface imperfections. The analysis of cores takes time, and therefore, it is difficult to determine the existence of a problem and intervene at the right time. In addition, the core does not represent the whole anode due to the non-homogeneity of anodes. A validated online anode quality control system can highly improve the situation. In this article, an electrical resistivity measurement method developed for this purpose is presented.

Jan 1, 2014

By Denni Nikols, Farrukh Z. Khan

"Highvale Mine, located at Wabamun, Alberta, produces thermal coal for TransAIta's Keephills and Sundance generating plants. Overburden stripping in the mine is conducted by draglines which normally operate on top of the overburden bench. In certain areas oj the mine, however, these overburden benches are susceptible to slope failure. In these areas, due to safety considerations, the draglines are utilized in the less productive chop-cutting mode, supplemented by mobile equipment where the bench height exceeds the dragline chop-cutting limit. This paper proposes maintaining the draglines in their normal digging mode through areas of unstable or jailed overburden, by utilizing a dragline carried toe buttress 10 ensure adequate bench stability. The data requirements and methods of slope analysis to design a toe buttress across an unstable highwall area are examined in rigorous detail. INTRODUCTIONLocationHighvale Mine is owned by TransAlta Utilities Corporation and operated under contract. It is Canada's largest coal mine with an annual coal production in excess of II million tonnes. The mine is located approximately 80 km west of Edmonton on the south shore of Wabamum Lake (Fig. I) and production is currently provided by three pits 02. 03 and 04 (Fig. 2). The entire coal production is consumed at the nearby Sundance and Keephills power generating plants.ScopeThe mining operation at Highvale Mine has had occasional slope stability failures of its high wall overburden bench. This paper examines one such failure which occurred in the summer of 1983 at Pit 03. In addition to an investigation of the failure, Terracon was asked to recommend mine operation procedures which would minimize the impact of these slide zones on dragline productivity. A method of removing the failed material by utilizing the dragline in its normal digging mode is designed. The method's advantages and disadvantages as well as the required support procedures are reviewed."

Jan 1, 1989

By Ian S. Thompson

"Exploration properties form a continuum from grass roots to those with favourable geology, geochemical and/or geophysical anomalies, mineralization, showings (prospects), and finally to those with defined mineral deposits. Often properties exhibit a composite of these categories.The most problematic to value are properties or deposits that are not economically exploitable at the time of the valuation, due to a lack of exploration, insufficient grade or tonnage, poor mining conditions, or the imposition of socioeconomic, environmental, or legal constraints.Various acceptable methods of valuing the range of all such mineral properties or deposits are reviewed. Some inappropriate methods are also discussed.BIOGRAPHYIan S. Thompson is President and Principal of Derry, Michener, Booth & Wahl Consultants Ltd. (DMBW), an independent consulting practice, specializing in exploration, ore reserve estimations, engineering and valuations of mineral properties.Mr. Thompson is a graduate in Honours Geological Sciences from the University of Toronto with over 35 years Canadian and International experience in mineral exploration and development, including the discovery of base metal. gold and uranium deposits.DMBW is affiliated with DMBW, Inc. in Colorado, and works with independent engineering and financial groups in North America, Europe, Australia and Africa.Mr. Thompson is a national member of CIM; the Associations of Professional Engineers of Ontario and British Columbia; The Geological Association of Canada; The Society of Economic Geologists; The Prospectors and Developers Association of Canada and the BC and Yukon Chamber of Mines.INTRODUCTIONThis paper is presented in response to the request of the Mineral Economics Society of the Canadian Institute of Mining and Metallurgy for a Review of Approaches to Valuation of Mineral Properties, as recommended by the TSE/OSC Mining Standards Task Force.Exploration properties with undeveloped mineral resources range from grassroots acreage without exploration history, to those containing mineralization (or a mineral resource) that is insufficiently explored, to well explored deposits which lack either continuity, or sufficient grade/tonnage, or have poor mineability or metallurgy, such that they are not currently exploitable at the time of the valuation. This does not imply that they do not have value."

Jan 1, 2003

By R. S. Adhikari

This paper presents an innovative computer vision method for condition assessments of bridges with multiple defects in bridge elements using digital images. This work utilizes 3D model of existing bridges and overlays digital images on 3D model to simulate on-site visual inspection. The analysis of element condition index (ECI) of bridges requires information about the severity and extent of defects in elements. In general, ECI is evaluated manually during routine bridge inspection considering the severity of dominant defects. The evaluation of ECI with multiple defects needs to be addressed with consideration of dominant defect as well as the interaction among defects. However, Image-based quantification techniques largely depend on geometry of objects (i.e. shapes). Shape vectors of a given object change as they are translated, rotated, and scaled with different magnitudes. This work considers shape preserving algorithms such as, affine and projective transformation for proper image alignment. Semi-automated approach for detection and quantification of concrete distress such as cracks and spalling are considered for the defects analysis. The proposed methodology ensures the consistency in reporting ECI and eliminates the shortcoming of traditional approaches.

Aug 1, 2013

By Marc C. Bétoumay

Workplace safety, health, climatic conditions and rising oil prices are aspects that are important to the mining industry. The need for cleaner energy for underground mine vehicles is requiring serious consideration. A number of alternate energy systems offer clean solutions to diesel emissions while maintaining the current liberty of vehicle movement. This watershed article provides a broad comparison of cleaner diesel and alternative energies for underground production vehicles. Most alternate energies and clean diesel have already been tested in underground production vehicles. There are no technology gaps that would prevent the development of commercial alternative energy power plants, but in the case of alternate energies, second and third generation versions will be required to fully test for safety and operation viability. Full regulatory development is also required and could be done in parallel to power plant testing. Vehicle operation and maintenance manpower would be the same for alternate energy application as for clean diesel. Capital cost for alternate energy power plants will remain higher until the medium term. Owing to significant ventilation savings possible with alternate technologies, operating costs would be reduced.

May 1, 2011

By Nick Vayenas

This paper discusses the application of a commercially available state-of-the-art PC discrete-event simulation modeling software, called Promodel, for simulating a typical underground mine hoist system in the Sudbury mining region, in the province of Ontario in Canada. The reasons for using Promodel as a two-dimensional simulation development tool is its simplicity in use and its capabilities to provide enough flexibility to meet the modeling requirements of a mine hoist system. General information of a mine hoist system was collected for building the model. Example of the model?s output is also presented. The application of Promodel in underground mining offers a powerful, two-dimensional simulation environment in an affordable price for mining engineers to analyze and study operational problems. This hoist simulation model is an intuitive demonstration of the mine hoisting elements and the operational logic of the hoist, based on which optimization of the entire mine system materials flow can be considered as part of a mine cycle management feasibility study.

Oct 1, 2009

By Thomas E. Shumka

ASTM E2905 describes a two-part standard for electromagnetic methods for preparation and examination of ring gear teeth in the mining sector for SAG and Ball Mill ring gear drives, including pinions? particularly on the addendum, dedendum, and root areas. This practice addresses the need to detect surface breaking flaws electronically and to have the ability to accurately size any surface breaking cracks found on cast and forged SAG and ball mill ring gear and pinion teeth faster and more effectively than other methods. Eddy-current surface arrays are seeing increasing use throughout the industry for the detection of surface breaking flaws in conducting materials. Example applications include examinations of pipelines, bridges, engines, aerospace structures, and any conducting material for surface breaking flaws including cracks. In addition, model-based methods are being used to size cracks accurately found in the addendum, dedendum, and the root of SAG and ball mill girth gear teeth. As visual interpretation of a surface breaking discontinuity on gear teeth is the normal analysis, the colors and 3D images that are provided with this technique, help with visualization and therefore are absolutely invaluable in such circumstances. This practice will help to standardize the use of this nondestructive testing approach.

May 1, 2013