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By CIM Mineral Resource, Mineral Reserve Committee

The CIM Mineral Exploration Best Practice Guidelines (the Exploration Guidelines) have been prepared to assist professional geoscientists and engineers to conduct consistently high-quality work in order to maintain public confidence. The Exploration Guidelines are meant to assist professional geoscientists and exploration practitioners in planning, supervising, and executing exploration programs. In Canada, there are generally two types of public resource reporting: “Disclosure”, as defined by NI 43-101, is the reporting of technical information to the public and market participants for securities legislation purposes where a Qualified Person (QP) must be involved, and reporting of exploration information for governmental agencies to support obligations under laws including the Mining Acts of each of the Provinces and Territories. The Exploration Guidelines are also relevant where the results will not be publicly reported but are intended for internal company use. While this document is intended as guidance for work conducted or supervised by geoscientists in Canada, many of the practices described herein can be adapted to mineral exploration activities in other countries. The Exploration Guidelines are not intended to inhibit original thinking, or to prevent the application of new approaches that may develop into fundamental components of successful mineral exploration programs. Rather than provide prescriptive solutions to specific issues, they include general guidelines for current professional practice and to demonstrate and defend the merits of new methods. These guidelines do not preclude individuals and companies from developing more detailed guidelines specific to their own requirements. The initial version of the Exploration Guidelines was prepared by the Canadian Institute of Mining and Metallurgy and Petroleum (CIM) Exploration Best Practices Committee and adopted by CIM Council on August 20, 2000. On January 9, 2018, CIM Council formed a new committee, the Mineral Resources and Reserves Committee (CIM MRMR Committee) with a mandate to, among other things, update the Exploration Best Practice Guidelines. The mandate for the committee was accepted by CIM Council on March 2, 2018. The new document was adopted by the CIM Council on November 23, 2018.

Nov 23, 2018

By Peter L. Sheehan, David A. Fawcett, Dennis C. Martin

"Smoky River Coal Limited has successfully completed a major program involving the pattern rock anchoring of a high, steeply dipping footwall slope. The slope dips at approximately 65 to 70 degrees to the north, is benched for the upper 200 feet, is supported with rock anchors for another 240feet, and is unsupported at the pit bottom. In addition to the height and steepness, several structural features including shears, rolls and stratigraphic pinch- outs complicate footwall stability.This paper presents an overview of the project with descriptions of the engineering geology and footwall design, anchor installation, instrumentation and monitoring and a cost summary.IntroductionSmoky River Coal's mines are located in the foothills of the Rocky Mountains near Grande Cache, Alberta, approximately 200 miles west of Edmonton. The Smoky River coal leases were initially developed in the late 1960s and, except for minor shutdowns, have been in continuous operation since 1969 producing a low volatile metallurgical coal, mainly for the export market. Initial coal production was from underground mines; sur face mining started in 1971, and a large surface mine, No.9 Mine, was opened in 1974. Since that time, a number of open pits have been mined within the No.9 Mine area. Surface mining is by conventional shovel-truck method s with the use of a backhoe for mining the narrow pit bottoms.Coal recovery is mainly from the No.4 seam, which has a typical unstructured thickness of 20 feet. The most attractive opportunities for open-pit mining exist in areas of over thickening of the coal seam in the hinge zones of synclines and anticlines and in dip-slope situations. The mining of the more structurally complex pits and steeply-dipping footwall slopes requires that consideration be given to footwall stability."

Jan 1, 1988

By K. Schimann, H. D. Knipping, J. P. Fouques

"RESUMELe gisement d 'uranium de Cigar Lake, dans la région de l'Athabasca au nord du Saskatchewan, fut découvert en mai 1981 par Cogema Canada Ltée, opérant pour Ie compte de la ""Waterbury Lake Joint Venture"".Le corps minéralisé. qui est dépourvu de toute expression directe en surface, est situé a la discordance entre les met sédiments du wottaston Group (Protérozoïque inférieur ou Aphébien) et les grès de l 'Athabasca (Protérozoïque moyen ou Hélikien), à une profondeur de 410 a450 m.Fin 1984, Ie gisement était reconnu par 105 sondages minéralisés repartis sur une longueur de 1800 m, pour une largeur comprise entre 25 et 105 m. 11 se présente sous forme d’une lentille aplatie de 5 a30 m de puissance, et montre une remarquable continuité d'ensemble. Une ride ou bombement topographique de la discordance est associée au gisement surtoute sa longueur.A l'échelle régionale, le corps minéralisé à est associe à un corridor structural d’orientation est-ouest, a l'intérieur duquel des facies particuliers aténdance blast mylonitique sont développes dans les formations métapolitiques agraphite du socle métamorphique. Il est entouré par un halo d'altération très important, caractériser Ie développement de minéraux argileux alumino-magnesiens (illite-chlorite).La minéralisation est située, pour la plus grande part, dans les grès d'Athabasca, et se compose essentiellement d'uraninite et de sulfo-arseniures de nickel et de cobalt,De nombreux levés géochimiques et géophysiques ont été effectues dans la région de Cigar Lake. Aucune anomalie ne peut être associée directement au corps minéralise, mais la combinaison des données en provenance de plusieurs sources s’est révélée fort utile au niveau de l’interprétation géologique régionale et de la définition des cibles de sondages a l'intérieur des zones reconnues favorables.Le gisement de Cigar Lake présente de nombreuses analogies avec plusieurs des gites classiques de la région de l'Athabasca; il est caractérise en particulier par l'intensité des phénomènes d’altération et la présence de minéralisations extrêmementriches.En 1984, les réserves géologiques globales estimées par géostatistique sur I ‘amas minéralise principal s 'élevaient a 110 000 tonnes d'uranium, aune teneur moyenne de 12.2%, avec une précision de 25% à l'intervalle de confiance de 95%.ABSTRACTThe Cigar Lake uranium deposit, in the Athabasca area of North Saskatchewan, was discovered in May 1981 by Cogema Canada LId., as operator of the Waterbury Lake Joint Venture. The deposit, which is devoid of direct surface expression, is located at the unconformity between the Lower Proterozoic (Aphebian) Wollaston Group meta-sediments and the Middle Proterozoic (Helikian) Athabasca sands tone, at a depth of 410 m to 450 m below surf ace.AI the end of 1984, the deposit had been defined by 105 mineralized holes over a length of 1800 m and a width of between 25 m and 105 m. It has the shape of a flat-lying lens 5 m to 30 m thick and shows a remarkable longitudinal and latera continuity from the information obtained to date. A well-defined bulge of the unconformity underlies the mineralized zone over its entire length.The deposit appears to be controlled by an east-west-trending structure within which a particular rock facies (""augen gneiss"") has developed in the graphitic metapelites of the Wollaston Group. It is surrounded by a strong alteration halo affecting both sandstone and basement, characterized by extensive development of Mg-A I rich clay minerals (illite-chlorite).The mineralization is hosted principally by the Athabasca sandstone, and consists mainly of uraninite and sulfo-arsenides of nickel and cobalt.Numerous geochemical and geophysical surveys have been carried out in the Cigar Lake area, and no specific geochemical or geophysical anomaly can be directly associated with the mineralized body, although there may be locally a good coincidence. However, a combination of several methods proved extre"

Jan 1, 1986

By Julie Dénommé

Today few in business would argue with the idea that we are living in a world that is Volatile, Uncertain, Complex, and Ambiguous. Coined VUCA by the US Army War College, these four words define the ?turbulence? and ?continuous white water? that the business literature has been documenting for the last decade. This VUCA world became even more relevant to business in 2007 when the Institute for the Future fellow Bob Johansen published the idea of transforming VUCA into Vision, Understanding, Clarity, and Agility. We call this VUCA Prime (VUCA'), and place an infinity loop (8) between them to show their dynamic interaction. This paper presents an exploration of the impact of VUCA 8 VUCA' on business and the conditions under which these dynamic forces help to successfully navigate change.

Oct 1, 2010

The construction, commissioning and operation of a continuous pilot-scale selective agglomeration (oil agglomeration) unit are described. This plant has been used to recover fine coal from an effluent stream that is produced by a jig plant which scalps the coal from a New South Wales (Australia) colliery. The reject slurry is extremely fine (66.5% minus 53 um) and has an ash content of approximately 40%. The pilot plant can treat up to 0.3 tonne/h of this slurry, producing average product ashes as low as 9.1% and tailings ashes greater than 80%. The average yield observed was62%, which corresponded to a recovery of coal material of 88%. The operation of this pilot plant yielded data that enabled an economic assessment of this type of processing to be carried out. This study showed that selective agglomeration is an economically viable process for eliminating the substantial losses of coal to tailings ponds and minimizing consequent disposal and environmental problems. A commercial plant has been constructed and commissioned on the basis of the data obtained from this pilot-scale operation.

Jan 1, 1979

By Stephan Buys, Dan Curry, Chris Rule

"The use of fine grinding (FG) in mineral processing is well established. The application of FG in the South African platinum industry is more recent and it’s use in the recovery of PGM’s from dormant tailings dams is unique. Anglo Platinum uses IsaMill FG technology at their Western Limb Tailings Retreatment project (WLTR) near Rustenburg in the North West Province of South Africa.In December 2003, Anglo Platinum commissioned the first purpose built tailings re-treatment facility for PGM recovery in South Africa. The concentrator re-treats Merensky ore tailings from concentrators that operated early last century. The WLTR facility takes advantage of modern technology, such as FG, to economically recover PGM’s from material historically considered as waste. The WLTR concentrator has a capacity of 4.8 Mtpa, and has been designed to easily expand to 10.8 Mtpa. The flow sheet includes recovery of tailings by high pressure water monitoring, ball milling, rougher flotation, rougher concentrate regrinding and cleaner /recleaner flotation.The rougher concentrate is reground in an IsaMill, which is a stirred mill that operates with inert silica sand grinding media. For this project, Anglo Platinum required a stirred mill of a unit size not previously available. Xstrata Technology and Anglo Platinum collaboratively developed the largest wet, fine grinding mill available; the M10,000, 2.6 MW IsaMill.The use of IsaMill technology was enabling for the WLTR project, as it allowed smeltable concentrate grades to be produced from the oxidised, slow floating tailings. The economics and practicality of fine grinding has fundamentally changed with the M10,000 IsaMill. Flotation is transformed by high intensity attritioning in the inert media environment, and the narrow size distribution of product in open circuit configuration. The use of conventional steel media grinding to improve fine particle flotation is limited due to the oxidation of liberated mineral surfaces inherent in these environments."

Jan 1, 2005

By J. K. Afidenyo, J. Osei-Owusu

"The Obuasi Mine of AngloGold Ashanti Limited has been operating the world’s largest Biooxidation Plant at its Sulfide Treatment Plant (STP) in Ghana, using the Gencor Biox® technology since February 1994. The Biox® technology was preferred to other alternative methods of treating refractory sulfide ores such as roasting, pressure oxidation and nitric acid leaching due to among other reasons, its lower capital and operating costs, reduced technical risk, relatively benign environmental impact and its ease of operation and maintenance in a remote location.STP has since commissioning succeeded in operating this technology successfully but not without some operational problems. The Plant has seen a number of upgrades and modifications in its circuits which were motivated by cost, operational and throughput constraints.The objective of this paper is therefore to highlight the mine’s experience in the treatment of its complex carbonaceous refractory sulfide gold ores with emphasis on plant operations and improvements such as the Biox® reactors expansion, flotation concentrate upgrade project and neutralization circuit modifications. The Biox® Plant operating cost is also discussed.INTRODUCTIONThe Obuasi mine forms part of the AngloGold Ashanti Group of Gold Mines. It is located in the Adansi West District of the Republic of Ghana. The mine is primarily an underground operation, although some surface mining still takes place. Ore is processed by two main treatment plants: the Sulfide Treatment Plant (for underground ore) and the Tailings plant (for tailings reclamation operations). A third plant, the Oxide Plant, is used to batch-treat remnant opencast ore and stockpiles, of which there are adequate tonnages to keep the plant operational until 2008.Though reference is made in this paper to the Tailings and Oxide Treatment Plants, the main focus will be on the Sulfide Treatment Plant."

Jan 1, 2008

Session 1 ? Intro to MiHR ? Business Case for Aboriginal Inclusion ? Overview of the Mining HR Guide for Aboriginal Communities ? Two presentations of Programs featured in the Guide ?? The RAP Program from NWCC ?? First Nations Youth Employment Program PDAC-MM Session 2 ? Presentation from MAC ? Taking up the AFN Corporate Challenge ? Presentation on Mastering Aboriginal Inclusion in Mining About MiHR Who we are: ? National Sector Council for the Minerals and Metals Sector ? 18-person Board of Directors ? 100+ Industry Leaders volunteer on our project committees ? PPP - Funded by HRSDC and industry What we do: ? Identify national HR challenges and opportunities for the minerals and metals industry ? Create national solutions through collaboration, partnerships and Synergy

May 1, 2009

By Kim Wiwchar, Elizabeth Mbaja, Lynne Dang, Jim Furey, Anita Marks

"Suncor Energy Inc., located north of Fort McMurray, Alberta, commenced pilot scale operation using a CPT 4’ diameter flotation column in March 2003. This larger scale trial follows two previously successful flotation column bench scale tests. They included an April 2002 trial with a 2.4” inner diameter column from the University of Alberta and a 20” diameter CPT column in August 2002. The column receives middlings stream feed from one of Suncor’s deep cone separation cells and is operated in parallel with a set of WEMCO flotation cells. The recovery, tails losses, and concentrate quality are being compared between the two systems. The column, to date, has been tested with all types of run of mine ore grades. Variables such as wash water flow and temperature, sparger nozzle size and location, sparger air/water flow rates, and column residence time has been adjusted to achieve better recovery and final product quality.Used in many mineral processing applications, column flotation is primarily used for the final stage of sulphide cleaning and flotation of phosphate or iron ore. As well, mechanical cells are often used in combination with a column to retrofit an operation and to produce a cleaner product.Initial results prove that this is the first successful application of a flotation column in an oilsand application. If viable, it will be an inexpensive process for recovery of bitumen from a middlings stream and able to produce a final product suitable for froth treatment.INTRODUCTIONSuncor’s oilsand is surface mined from the Athabasca Oilsand deposit north of Fort McMurray, Alberta. The oilsand is then mixed with hot process water (HPW) and the bitumen is slurried in a pipeline. Large separation cells as shown in Figure 1 float off the bitumen product, which is then steam or static deaerated and sent to Secondary Extraction for further cleaning. The tails stream from the cell is sent to the Final Tails Pumphouse (FTPH) for processing. The tailings flotation froth product gets recycled to the separation cell oilsand feed. The tailings are pumped from the FTPH to tailings ponds. The middlings stream is drawn off the separation cell approximately 9’ from the froth overflow level. It runs down, by gravity, to the scavenger banks for bitumen recovery. It was from this stream off of the Line 6 Separation Cell that the feed to the Canadian Process Technologies Inc (CPT) flotation column was taken."

Jan 1, 2004

By George P. Demopoulos, Nima Parsi Benehkohal, Marianna Uceda

Lithium-ion batteries (LIBs) find wide range of applications from portable electronics to electric cars and stationary storage or renewable energy. LIB electrode fabrication is done through mixing the active material (Li-ion host) with carbon (conductive component) and polyvinylidene fluoride (PVDF), which acts as a binder. These components are dissolved in N-methyl-2-pyrrolidone (NMP) to form a paste which is then doctor bladed onto the aluminum current collector. NMP is a toxic chemical and the overall fabrication process remains costly. Efforts are made of eliminating NMP by (1) replacing the binder and (2) using a new fabrication method. Of particular interest among these new methods is electrophoretic deposition (EPD). Via the application of DC potential, particles in suspension can be electrophoretically deposited on different conductive substrates in a relatively fast rate rendering EPD feasible for industrial application. A key aspect for successful application of EPD is the formulation of a stable suspension. Within the McGill HydroMET group, we explore the potential of EPD in fabricating LIB electrodes having demonstrated its effectiveness in the case of P25 nanotitania/carbon anodes. The performance of EPD fabricated TiO2/C electrodes is compared to standard PVDF-based electrodes and shown to have comparable charge capacity. This method is now being extended to other electrode materials. In this paper an introduction to the EPD method will be made and subsequently its use in fabricating LIB electrodes will be described. The performance of the fabricated batteries is evaluated via galvanostatic charging/discharging and cycling tests.

Jan 1, 2016

Project Located in northwestern British Columbia 70km West of Cassiar Highway Galore Creek Project and Road Access Corridors Designated For Mineral Development in Stikine-Cassiar Land Resource Management Plan (LRMP)Approved in 2000Strong BC Government, local community and Tahltan First Nation Support for Project

May 1, 2006

By T. A. Utigard

To improve recoveries of Ni, Cu and Co in the Inco flash furnace, a new operating concept was investigated. By adding sufficient coke to form a supernatant coke layer, a reducing barrier would form allowing for improved reduction of descending oxidized sulfide mineral particles formed in the flame. The objective of this investigation was to study the kinetic mechanism and efficiency of the coke layer to produce a sulfur deficient matte. The mechanism and rate of carbon reduction of each of the phases formed in the flash flame, i.e. sulfides and oxysulfides were investigated by means of X-ray visualization tests. Graphite-slag reduction was also conducted for comparison purposes. In the case of slag, poor wettability and the formation of a gas film on the surface of the carbon reductant are often blamed for limiting the reaction surface area that ultimately results in poor reaction kinetics. The X-ray visualization tests confirmed that matte and oxysulfide wet coke better than slag and that the rates of reduction of matte and oxysulfide are faster than that of slag.

Jan 1, 2005

By T. Imgrund, A. Bischoff, S. Spürk

"Specific conditions of underground coal mines at great depth, such as high temperatures, high rates of methane inflow and natural ventilation pressure provide considerable challenges for the reliable design of appropriate mine ventilation systems. For decades coal mining in Germany has coped with these extreme circumstances. Based on these experiences appropriate software tools for simulating mine ventilation networks have been developed and continuously enhanced. This paper examines differences in the simulation results and underlying calculation methods of two software solutions. The analysis is based on the comparison of FlowNetTM and VentSim DesignTM (Version 5.1) regarding the accurate prediction of fluid mechanical quantities and their validation with real measurements. A special focus lies on exceptional ventilation scenarios typical for deep coal mines, like gas inflows, fire events and buoyancy effects. The purpose of the comparison is the future utilization of the experiences gained during mining at up to 1,500 m depth for state of the art ventilation design. INTRODUCTION Ventilation is an essential component of mine operations—as providing fresh air to workplaces, diluting and removing explosive, toxic or asphyxiating pollutants and assuring sufficient climate conditions. On the other hand, the costs of ventilation contribute to a large extend to the overall operating costs of a mine, as the share in the energy consumption of a mine may be in the range of 25–50% (Belle, 2008). Accordingly, proper design of ventilation systems has been a task since early times. Consequently software for modelling of ventilation networks has been developed in order to improve efficiency and accuracy of calculations (Maleki, 2018). Compressible flow has not been considered by initial ventilation modelling software tools. In Germany, the consideration of changes in airflow density—depending on pressure and temperature—in the algorithms of ventilation simulation software has been started in 1974 by Duepre & Hofbauer. This development had been continued by the Pruefstelle fuer Grubenbewetterung (Test Centre for Mine Ventilation) and resulted in the release of a computer ventilation software named “Wetter”. The mine inspectorate of the German state of North Rhine-Westphalia, which supervises the major coal mining district in Germany, declared ventilation simulation based on compressible flow being “state of the art” in 1985 (Pollak, 1985). This pronouncement made allowance for assessing the consequences of underground fires and downtimes of main fans based on advanced software solutions."

Jan 1, 2019

By M. J. Collins

"Autoclaves were first used in the metallurgical industry in 1893 to recover alumina from bauxite. In the 1940s and 1950s, several high temperature and pressure processes were invented in the laboratory of Professor Frank Forward at The University of British Columbia, in parallel with advances in equipment and processes by the Chemical Construction Corporation. Sherritt Gordon Mines Limited enlisted these groups to help develop the nickel sulfide ammonia leach process that was commercialized in 1954. Autoclave processes that have since been commercialized include high-pressure acid leaching of laterites, zinc pressure leaching, and pressure oxidation of refractory gold feedstocks. RÉSUMÉ En 1893, l’industrie métallurgique est la première à utiliser les autoclaves pour l’extraction de l’alumine dans la bauxite. Dans les années 1940 et 1950, plusieurs procédés à haute température et à haute pression sont inventés dans le laboratoire du Pr Frank Forward de l’université de la Colombie-Britannique (UBC) ; parallèlement, la Chemical Construction Corporation fait de grands progrès en matière d’équipement et de procédés. Sherritt Gordon Mines Limited fait appel à ces groupes pour qu’ils aident la société à développer le procédé de lixiviation du sulfure de nickel dans de l’ammoniaque, commercialisé en 1954. Les procédés de lixiviation en autoclave commercialisés depuis incluent notamment la lixiviation acide à haute pression de latérites, la lixiviation sous pression du zinc et l’oxydation sous pression des matières premières de l’or réfractaire.INTRODUCTION Autoclaves are chemical reactors that are built to contain processes taking place at elevated pressure. They are used in metallurgical refineries throughout the world to take advantage of the increased reaction kinetics and different reaction products that can be obtained in aqueous systems above the boiling temperature at atmospheric pressure. The word autoclave comes from the French “auto” and the Latin “clavis” and literally means self-locking—that is, the core distinguishing feature of an autoclave is that it includes a means for pressure regulation (e.g., a pressure relief valve). Denis Papin (Figure 1a), one of the inventors of the steam engine, was the first to make use of a safety valve to control steam pressure. He is credited with inventing the autoclave in 1679. Papin’s “digester” (Figure 1b) was a type of pressure cooker that was originally used to liquefy bones. Most commercial autoclaves are horizontal, multicompartment vessels with mechanical agitation, as shown in Figure 2a; however, the steam-agitated Pachuca vessels used to leach laterite ore in Moa, Cuba (Figure 2b), are also classified as autoclaves according to the self-locking definition provided above."

Jan 1, 2018

By Kim Le Roux

Cemented paste backfill (CPB) is a relatively new material that is increasingly being used in open stope mining across the world. The advantages offered by this high density tailings backfill include: a lower total cost associated with backfill placement, reduction of excess water underground; and the elimination of the need to process the tailings prior to placement. However, almost all backfill design is based on the performance of laboratory prepared samples since it is difficult to obtain undisturbed samples and conduct in situ testing due to the lack of access to backfilled stopes and the safety concerns in accessible areas. The logistical problems associated with conducting in situ testing and obtaining undisturbed samples of cemented paste backfill (CPB) has lead to the reliance in the mining industry on performance data obtained from laboratory prepared CPB samples. The degree to which these laboratory prepared samples represent the actual in situ condition is not well defined, partly because the influence of the mixing, transport and placement process on the material properties it is not well understood. Therefore, there is a need in the industry to understand how the material properties and hence the performance of the laboratory prepared CPB compares with in situ material. This paper reports the findings of an investigation into the in situ properties of CPB at a gold mine in Northern Ontario. A combination of in situ and laboratory testing, conducted on undisturbed samples, was used to quantify the in situ properties and performance of the CPB. These results were then compared to those of a laboratory based investigation of the same CPB. It is evident from this investigation that the bulk properties of the in situ CPB are different from those of the laboratory prepared CPB. The most significant observed differences are that the in situ CPB has a higher void ratio and a lower degree of saturation than the laboratory prepared material. The implication of these differences on the stability and performance of the CPB will also be explored in this paper. 1

May 1, 2002

By Chuck Edwards

"Cameco operates the high-grade McArthur River uranium mine in northern Saskatchewan, and is constructing the high-grade Cigar Lake uranium mine. Cameco has studied the concept of underground milling of high-grade uranium ore. Compared to conventional milling on surface, the underground milling scheme appears to offer significant cost savings and a lower environmental impact. This paper describes the underground milling scheme, presents process flowsheets and plant layouts, and provides an assessment of potential benefits from underground milling.INTRODUCTIONCameco CorporationCameco is the world’s largest uranium producer, with three operations in Saskatchewan (Rabbit Lake mine/mill, McArthur River mine, and Key Lake mill), two in the United States (Crow Butte and Smith/Highland ISL operations) and two new mines being developed in Canada (Cigar Lake project) and Kazakhstan (Inkai project). Cameco provides uranium fuel refining and conversion services at its Blind River and Port Hope facilities in Ontario. Cameco is part owner (31.6%) of Bruce Power that leases eight nuclear power plants located in southern Ontario. Cameco is the majority shareholder in Centerra Gold Inc., which operates gold mines in the Kyrgyz Republic and in Mongolia.Global Uranium Production RequirementsCentral to Cameco’s view of future uranium supply requirements is the belief that the world is experiencing a nuclear renaissance. This belief is supported by a number of developments, including:•,?Countries representing half the world’s population are now constructing new nuclear power plants. Many countries without nuclear power have begun to plan for it, seeking reliability, clean air and energy independence.•,?Accelerated growth for this industry is also becoming much more likely. In Asia, primarily in China and India, 92 reactors are under construction, on order or planned to help meet rapidly expanding economic needs. Other Asian countries, such as Vietnam and Indonesia, with large populations and rapidly growing economies, are also expected to follow.•,?In the United States the “Energy Policy Act of 2005”, the first energy legislation introduced in over a decade, was signed. This legislation includes provisions recognizing, for the first time at a national level, the clean air contribution of nuclear energy and its critical role in meeting energy security. Upon signing this landmark legislation President Bush stated, “We will start building nuclear power plants by the end of this decade.”"

Jan 1, 2007

By K. Parameswaran, A. Veek, A. Fernandez, P. Safe

ASARCO LLC (Asarco) Hayden Copper smelter, in Hayden, Arizona, has operated continuously (except for minor labor and economic curtailments) since 1912. The current plant configuration comprises INCO flash smelting, Peirce Smith (P-S) converting and fire refining/anode casting. In order to comply with the U.S. Environmental Protection Agency (EPA) 1-hour National Ambient Air Quality Standards (NAAQS) for sulfur dioxide promulgated in June 2010, the Hayden smelter had to increase overall sulfur fixation from approximately 95 % to 99+ %, requiring a retrofit of the existing converter department and upgrade of associated emissions controls systems. The Converter Retrofit Project (CRP) involved replacing the five existing 13’ diameter Peirce-Smith converters (2 blowing, 2 hot standby) with three new 15’ diameter Peirce- Smith converters (1 blowing, 1 hot standby) to allow for more effective process gas capture using the existing acid plant contact section. Significant upgrades were made to the acid plant wet gas cleaning section and converter primary gas handling system to improve capture performance, reliability, and sludge handling. In addition, a new tertiary gas capture system was installed to further minimize fugitive emissions from the converter aisle. The existing furnace tapping ventilation ESP was replaced with a new baghouse to enable at least 50% SO2 removal using high-surface-area dry lime injection, which was also implemented on the existing converter secondary gas baghouse system. The first two converters and all gas handling system improvements were started up in April 2018, and the third converter was brought online in November 2018. This paper presents the regulatory context; genesis and rationale for CRP; detailed description of the project; challenges during commissioning; system improvements implemented, and design considerations made, and systems performance and process optimization achieved since startup.

Jan 1, 2019

By Tim Edwards, Richard Triglavcanin, Ian Arbuthnot, Darren Colwell, Brad Garraway, Ken Roberts

"In the mineral processing industries, there is an increasing need to design thickeners which are able to produce high density underflows usually referred to as “paste”.The behaviour of a flocculated suspension in compression needs to be well understood in order to arrive at a reliable thickener tank configuration (i.e. diameter, cone angle and depth) for a required paste result.As a suspension approaches paste consistency, it’s fluid characteristics change markedly. It develops a high yield stress, and may have an increased tendency to form agglomerates, which lead to a phenomenon known as “rotating beds”, “donuts”, or “islands”. These characteristics present challenges to the designer of the rake mechanism.The subject paper addresses the requirements for designing a paste thickener, covering the following topics:o Testwork for thickener sizingo Design of rake mechanismso Suspension rheology and effect on designo Case studiesTESTWORK AND SIZING FOR PASTE THICKENERSThickening slurries to the maximum possible density (paste) is becoming increasingly common. Applications such as Autoclave feed thickeners, paste backfill and some counter current washing (CCD) circuits are all examples of potential paste thickening applications. The principle of paste thickeners is that the compression zone is much deeper than on either high rate (HRT) or high compression (HCT) units; generally 3 metres or more. As the compression zone gets deeper, theunderflow density for a given flux rate (tph/m2) increases, as a result of two factors:1. Longer bed settling time. Settling flocs move relative to one another and release interstitial fluid when they are in compression. Increasing bed residence time achieves higher density underflow as more fluid is removed.2. The nett weight of the bed creates a compressive force on the settling flocs. This force increases with depth, so that the flocs at the bottom of the bed experience the highest compressive force. This represents the driving force to expel interstitial fluid and hence increase bed density."

Jan 1, 2005

By Manqiu Xu, Joe Holmes, Peter Wells, Peter Langlois, Germain Labonté, Jim Barrett

"The flowsheet for the Voisey’s Bay mill had to meet the challenge of processing an ore containing high pentlandite and chalcopyrite values in a largely pyrrhotite/troilite matrix. In the 1994-97 period, circuit development focused on making a high-grade copper concentrate and a relatively low-grade nickel concentrate. However, in 1998 a circuit with copper concentrate, high-grade nickel concentrate and a Ni/Cu middlings concentrate was specified. Following a three year project delay, work resumed on the flowsheet in 2001, and the target for the overall grade of the nickel concentrate was raised from 14% to 20% nickel. To achieve this target triethylamine tetramine (TETA) and sulfite pyrrhotite depressants were used in an all lime circuit. It later became evident that, with appropriate selection of collector and adjustment of the circuit by the addition of a scavenger on the scavenger cleaner, it would be possible to approach the grade of concentrate required without the use of pyrrhotite depressants. The recycle of water and the contained thiosalts was also proven to be instrumental in raising the grade.Construction and commissioning of the mill were fast-tracked with start-up of the mill in September 2005 some six months ahead of the original schedule. Ramp-up of both throughput and metallurgy was faster than any other recent nickel installations with tonnage being limited mainly by concentrate dewatering due to the higher than initially planned ore grades.INTRODUCTIONNickel was discovered in the vicinity of Voisey’s Bay by Chislett and Verbiski working for Diamond Field Resources in 1993 and the Ovoid deposit was delineated in the winter of 1994/95. By the end of 1995 the Ovoid had been well explored and at that time was thought to have a reserve of at least 30 million tonnes with an average grade of 2.83% Ni and 2.0% Cu. Drilling to the east of the Ovoid had indicated the presence of significant mineralization. In June of 1995, Inco Limited bought a 25% share in the Voisey’s Bay Nickel Company (VBNC) which was a subsidiary holding company set up by Diamond Fields. Inco also bought 8% of Diamond Fields and negotiated the right to sell all the nickel produced from VBNC for twenty years as part of this agreement. In April 1996, Inco bought the 75% of VBNC shares that it did not own."

Jan 1, 2007

By Vu Van Dong

Resource estimation is the science of determining the amount and quality of a given material in the ground that has the potential to be mined at a profit. This is because during this time computers have become more widely available and more powerful and software packages have become more comprehensive and user friendly. Over the past three years The Mining Geology Company with the support from Vinacomin Group has developed the Coal Geological Modelling and Reserve Estimation ? VMG system. The VMG system enables the geological and mining engineer to start at the reserve estimation for the mine design and planning. The VMG system enables the national and international standards (NI43-101, CIM-Canada; SAMREC Code, Africa, and JORC Code, Australia) and user friendly with menu driven thereby permitting the engineer with minimal computer training to rapidly learn and utilize the system. Geological and mining data input through digitized map files and drill-holes information files stored in the database that is an integral part of the VMG system with the main function for collection, validation, and recording, storing and processing of data will include both ?primary? (observation and measurement) and ?interpreted? data. It is recommend that data be stored digitally, using a documented, standard format and a reliable storage medium that allows for easy and complete retrieval of the data. The coal reserve estimation through standard polygon methods with the increased use of these mathematical techniques (geometrical modelling, geostatistical method, least square method, ?) over the last ten years corresponds, to some degree, to a decrease in both the amount of the coal deposit mapping and, in particular, coal seam structural interpretation and modelling, and permit rapidly evaluation of coal seam and overburden quality and quantity. The understanding of the relationship between the coal mineralization of interest and the likely related complicate geological processes and structure that govern its emplacement and geometry within the geological framework is essential to the establishment of the geological controls for coal mineralization. System outputs includes: drillholes summary reports, stratigraphy, cross-sections, isopach maps, structure, contour maps, premining and post mining topography maps, and 3D perspective view on coal seam structure.

Oct 1, 2009