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By L. Shasko, M. Hurlbert

As climate change is increasingly perceived as a problem, and fossil fuel based power production options are increasingly limited through regulatory restrictions and public distaste, future options become constricted. Reflexivity and social learning elicited through qualitative and mixed research methods offer important insight into what future power production pathways might be. Given factors of cost, baseload requirements, and energy density, options such as nuclear may be increasingly accepted. This paper explores this literature and possible methods of pursuing the reluctant acceptance of nuclear energy.

Jan 1, 2020

By M. Doucet

The introduction of high-nickel anodes to CCR in 2006 resulted in an increase of nickel in anodic slimes. Removal of the nickel in these slimes to below 3.0% is necessary in order to prevent slag viscosity problems in the subsequent pyrometallurgical step. A lower specification of 0.5% was chosen in order to minimize Ni losses to the slag and to recover this nickel as NiSO4. A 2-stage autoclave process, which was patented by CCR in 1992, was chosen to treat the high nickel slimes. Laboratory and plant?scale tests were performed in 2004 in order to validate the results of this process with the present slimes. These results along with corrosion tests were used to design two brick-lined autoclaves. These autoclaves were installed in October 2006 and successfully commissioned within 8 weeks. A "Design of Experiment" test program was performed in 2006 on an alternative autoclave process that reversed the cycles in the patented process. The effects of temperature and acid content were modeled using the results. The alternative process will be validated with the new autoclaves.

Jan 1, 2007

By J. A. Muñoz

In this work, short and long-term tests were performed using different massive mineral sulfide specimens (chalcopyrite, pyrite, sphalerite, galena, covellite and chalcocite) of museum grade and quartz of analytical grade in an acid medium containing silver ions. After attack, the samples were observed by SEM and products characterized by EDS. Parallel, massive specimens of pyrite (FeS2) and chalcopyrite (CuFeS2) were embedded in an epoxy resin, either electrically isolated or in electrical contact, and treated with silver ions in the presence of bacteria. Finally, massive chalcopyrite and pyrite electrodes were subjected to electrochemical measurements in an acid medium under different experimental conditions (addition of silver ions and inoculation). The results showed that silver deposition takes place preferentially on specific mineral surfaces: chalcopyrite, galena, covellite and chalcocite. The chemical reaction of silver ions with pyrite and sphalerite was negligible at low silver concentration (8 ppm). But sphalerite reacted with silver ions at higher silver concentration (100 ppm). In a mixture of chalcopyrite and pyrite, silver was deposited on the former surface creating new cathodic sites which sped up the electrochemical reactions of chalcopyrite dissolution.

Jan 1, 2007

By Serge Vézina

Environmental issues have evolved considerably over the last two decades. The main contributing factors, to name a few, have been the changing values of our modern societies, the globalization of trade and its linkage to environment, evolution and accessibility of information/communication technologies, better educated populations, climate change, long range transport of toxics and the increasing influence of NGOs and multistakeholders. As well, environmental management of mining operations had to be realigned in order to meet these new realities and to respond to more elaborated regulations oriented towards sustainability. Environmental Management Systems (EMSs) have emerged and have been introduced to meet not only the assurance of conformance to regulations but also to prevent pollution and to apply the continuous improvement of mining processes. EMS models have been developed and certification to international standards (e.g. ISO-14 001) is a common practice. Globalization has imposed challenges and additional requirements to environmental management. Developing a mine in emerging countries implies dealing with international agencies, local communities and a variety of government infrastructures to obtain a ?licence to operate?. This paper presents the structure of our EMS and how we have adapted its implementation to our operations in South America.

May 1, 2003

By Robert D. Brown

"All ten Canadian provinces have now tabled their 1981 /82 budgets . Only the provinces of Ontario, Quebec and British Columbia made more than minor modifications to their tax structures, with both Ontario and Quebec imposing major tax increases. In the past year, the federal budget was also released in the spring. Not so this year: we have that to look forward to in the fall!This month, Tax Notes presents a brief summary of the more significant tax changes introduced at the provinciallevels in the last months.Summary of provincial tax rate changesThe tax changes in this year's provincial budgets were both up and down- but there were far more tax increases than tax cuts.At the corporate tax level, two provinces, New Brunswick and British Columbia, increased their general corporate income tax rate; the former by two percentage points and the latter by one percentage point. Quebec, rather unexpectedly, sharply cut its corporate tax rate on business income, but increased some of its other business taxes at the same time. British Columbia reduced its corporate tax rate on small business income by two percentage points and Saskatchewan by one percentage point."

Jan 1, 1981

By P. E. Walker, M. E. Reed, R. C. Sims, B. Snowdon, D. E. Fallas

An advanced Flash Furnace feed system is the key to improving furnace performance. Clyde-WorleyParsons has developed a revolutionary pulseless pneumatic injection feed system technology, capable of delivering a range of benefits to operators of Flash Furnaces. The solution was created by combining the pneumatic conveying and injection knowledge, expertise and technology of Clyde Materials Handling with WorleyParsons' flash furnace process and operating experience. Optimal furnace burner performance requires the feed material to be presented to the burner as a stable, pulseless and accurately controlled flow, distributed evenly around the burner tip circumference. These simple requirements appear obvious, but are extremely difficult to satisfy in industrial environments and are not achieved by conventional feed systems. Our analysis of existing operating furnaces has identified the link between pulses in concentrate feed rate caused by conventional drag chain conveyors and rapid fluctuations measured in the furnace pressure. These fluctuations occur at a timescale close to the reaction shaft residence time and lead to unwanted instability in the primary furnace reaction zone - the flame. Through the use of the solution created by Clyde-WorleyParsons, it is predicted that the much more accurate control of feed rates achieved can lead to substantial improvements in furnace output, increased oxygen efficiency and better control of the composition of furnace liquids, such as matte, blister or slag. All these improvements lead to significant increases in smelter output and efficiency, and deliver high economic value compared to the cost of the feed system. Clyde-WorleyParsons' solutions can be deployed on greenfield sites or retrofitted, and therefore, have the capability to improve feed control at both new and existing smelters. This paper will discuss the field test work undertaken to date, the impact of findings and the ongoing analysis of linkages between instabilities in the various components of conventional feed systems and furnace pressure stability.

Jan 1, 2007

By K. D. A. Whaley

Abstract -The Captain North Extension deposit consists of five sulfide lenses hosted in cherty and chloritic metasediment that is bounded by quartz-eye rhyolite and laminated rhyolite . Lens 2 consists of sphalerite and galena with silver-rich tetrahedrite in chert. Lens 3 contains massive pyrite, with chalcopyrite and minor gold, gradational to minor pyrite in a chloritic metasediment . The other lenses are unexplored. The sulfides occur as beds, fracture infills, and disseminated grains. Reserves are estimated at 207 555 tonnes grading 7.38% Zn, 2.76% Pb, and 91.81 g/t Ag. The deposit is isoclinally folded, dips steeply west, plunges 50 degrees south, and is faulted out to the north, where drag folding has reversed the plunge. Minor cross-faults contain talc and sericite. High sphalerite but low pyrite abundances result in poor responses to standard electromagnetic techniques. Lens 3, which contains more pyrite than Lens 2, responds better to induced polarization and allows detection. Geochemical anomalies are found in a nearby swamp and stream, but an impervious till cover inhibits the development of soil anomalies.

Jan 1, 1992

By R. Tomás, J. B. Serón, M. Romana

The Slope Mass Rating (SMR; Romana, 1985) geomechanics classification was developed as a sequel of Bieniawski’s Rock Mass Rating (RMR) system, which was almost impossible to use in slopes due to the extreme range of the correction factors (up to 60 points of a maximum of 100) and to the lack of definition of them. A detailed quantitative definition of the correction factors is one of the advantages of SMR classification. During the last thirty years the use of SMR system has been extended to many countries from the five continents and, thus, it is time to review the most interesting developments. Both RMR and SMR are discrete classifications, depending on the values adopted by the variables that control the parameters. This can cause major changes in the parameters value due to small differences in the variables value, with changes in the final rock mass assigned quality. On the other hand, geomechanics quality indexes are extremely biased. To avoid this problem, some authors have proposed continuous functions for SMR. This classification has been also adapted for its application in heterogeneous and anisotropic rock masses, for high slopes, for is application trough stereographic projection and Geographical Information Systems, has been used as susceptibility rockfall parameters and has been included in the technical regulations of several countries. Additionally, some open access computer tools have been developed for the computation of SMR. Consequently, this paper reviews: 1) the most important modifications and adaptations of slope classifications which derive directly from SMR; 2) the use of SMR throughout the world; 3) many significant papers on slopes analysed with SMR all over the world; and 4) future trends in the use of SMR.

Jan 1, 2015

By T. ?kre, O. M. Dotterud, S. Haarberg, J. Thonstad, G. M. Haarberg

An electrowinning pilot plant has been constructed at Falconbridge Nikkelverk A/S, Kristiansand, Norway. The equipment consists of a mixing tank where the electrolyte composition and temperature are controlled, an electrowinning tank equipped with five cathodes and six anodes of commercial size and design and a dechlorination facility. Electrowinning experiments were carried out in this pilot plant using acid cobalt chloride solution from the cobalt tankhouse. Key parameters were varied to obtain an improved understanding of the cobalt electrowinning process, focusing on the detrimental deposition of cobalt oxide on dimensionally stable anodes. The extent of anode scaling was found to be dependent on the electrowinning conditions. Low pH, temperature and cobalt concentration resulted in less scale being formed, however at the expense of cobalt current efficiency and cell voltage, adversely affecting electrowinning production capacity and energy consumption. When operating at high acidity, pH in the anolyte was higher than in the catholyte, which is believed to be due to H+ ions taking part in the current transport across the diaphragm, migrating out of the bags surrounding each anode.

Jan 1, 2005

By W. Holyk

"Although lead, zinc, copper, and iron sulphides have been known for many years in the Bathurst region, the existence of large massive deposits was not known until the discovery of the Brunswick orebody in 1952. This was followed by the discoveries of the Anacon orebody in 1953 and the American Metals orebodies in 1954. There is no question as to the great importance of these large massive sulphide deposits, and no doubt that other sulphide deposits are to be found. The problem, of course, is where and how to find them.The discovery of the Brunswick and Anacon orebodies is attributed to geophysical work. The original discovery of the American Metals deposit is generally attributed to a regional airborne electromagnetic survey.It is generally stated that the Bathurst area is a geophysical camp, and this is essentially true, but in this highly competitive search for orebodies it is obviously impossible for an individual company to cover the entire area by a comprehensive geophysical survey. Some means other than geophysics must be used to narrow the target. The quickest, cheapest, and simplest method is geological investigations.It has been stated that nothing can be accomplished by geology in the Bathurst region, since the camp is largely covered with overburden. This is true only insofar as detailed work on certain properties is concerned. It is not true of the larger regional picture. Outcrops are scarce, but angular float is abundant, and precedent shows that angular float has moved but a short distance from its source.GeologyAeromagnetic maps published by the Department of Mines and Technical Surveys are the best guides to the geology and structure of the area. These maps supply factual information concerning the underlying rocks. When coupled with field investigations, they are very useful in the interpretation of regional geology and the selection of favourable areas. The discussion of the geology is accordingly centred upon the aeromagnetic maps. The following is essentially a working theory, based on geological facts as best reconciled with all other available information,"

Jan 1, 1949

By E. Benguerel, G. Monteith, L. Centomo, S. Pelletier

In early 2007, it became apparent that with changing concentrate feeds, the magnesium (Mg) load projected for CEZinc starting in 2009 and beyond would quadruple and overwhelm the current Mg process bleed capacity. A project was started, following design for six sigma (DFSS) standards, to select both the optimal process and to evaluate its target capacity for the Mg bleed circuit. The economic and process risks of under or over-designing while Mg reduction efforts were underway at the mines also needed to be evaluated. This paper describes the project methodology, the impact on the plant, and some potential optimizations for CEZinc's basic zinc sulphate (BZS) Mg bleed process.

Jan 1, 2008

By M. D. Gerst

The degree to which copper will continue to be in an integral part of the world economy in the future will depend largely on the dynamics of global economic development, the primary and secondary copper resource stock, technological change, and potential environmental constraints. We have characterized the copper cycle of 1994 for all of Earth's regions and for the planet itself (T. Graedel et al., Environmental Science & Technology, 38, 1242-1252, 2004) and recently updated that cycle to year 2000. In this paper, we compare various features of the 1994 and 2000 cycles. The three largest-using regions, Asia, Europe, and North America, all increased their absolute rate of copper use between 1994 and 2000, and all increased the per-capita rate of copper use as well. Globally, the use of copper increased by about 32%, from 11.7 to 15.3 million metric tons, while population increased by only 8%. Various changes are seen in scrap trade, finished products trade, and other parameters of the cycle. We conclude by considering how the rates of technological change and growth in demand, especially in Asia, may influence the copper cycle in the years ahead.

Jan 1, 2007

By P. M. Pearson

This paper describes the principles ()f systems engineering and their application to the various transport problems confronting the mining industry. The organization of mining operations into sub-system design problems is explained.

Jan 1, 1970

By A. Perucho, J. P. Harrison, A. Bedi, L. Alejano, L. Lamas, A. Sofianos, A. M. Ferrero, R. Migliazza, R. Olsson, J-F. Mathier

"In 2010, the Eurocode for Geotechnical Design, EN-1997-1:2004 (CEN, 2004), informally known as Eurocode 7 or EC7, became the Reference Design Code (RDC) for geotechnical design – including rock engineering design – within the European Union (EU). EC7 is one standard within the comprehensive Structural Eurocode suite, which as a whole has been also adopted by a number of other countries beyond the EU. EC7 is thus becoming a key design standard for geotechnical engineering worldwide.As part of the Structural Eurocode suite, EC7 requires designs to adhere to the principles of Limit State Design. However, it is not clear that current rock engineering design practice can satisfy this requirement. In addition, evidence is accumulating that EC7 is currently difficult to apply to, and may even be inappropriate for, rock engineering design. These issues may be due to the fact that the development of EC7 to date took place without any formal input from the international rock mechanics and rock engineering community.In early 2011 under the auspices of CEN (Comité Européen de Normalisation / European Committee for Standardisation), EC7 entered a formal period of maintenance which was aimed at improving the applicability and ease-of-use of the Code. This maintenance cycle will conclude in 2020 with the publication of a revised version of EC7.This paper describes a number of critical aspects for rock engineering in the context of EC7, inparticular the following:– the history of the Structural Eurocodes and the concepts they embody;– the nature of Limit State Design and the challenges and opportunities it poses for rock engineering design;– the formal means by which the Structural Eurocode maintenance cycle proceeds;– the plans currently being developed for improving EC7 with regard to rock engineering design and construction;– the unique and vital opportunity for the entire international rock mechanics and rock engineering community to comment on the Code and make suggestions for its improvement."

Jan 1, 2015

By Tony Breuer

Can international development NGOs and the mining industry find common ground and work together in the Third World? The Canadian Hunger Foundation/PARTNERS in Rural Development (CHF-PARTNERS) has, over the past forty years, implemented more than 800 rural community development projects in some 38 countries of Africa, Asia, and the Americas. Working with or for the Canadian mining industry offers both opportunities and risks. We can help a mining company ensure that the workers, their families and communities share adequately in the economic and social rewards from a mining operation in their area. We can contribute to the provision of sustainable livelihoods when an operation winds down. The company?s reputation as a good corporate citizen can be enhanced. On the other hand, mining companies and NGOs have generally very different values and missions. The risk of misunderstandings from conflicting motives and work practices is correspondingly high. Both partners must state their values and expectations clearly at the start of collaboration. The NGO must ensure that the company abides by acceptable ethical standards. It must not directly or indirectly subsidize a private company from its charitable donations. The mining company must satisfy itself that the NGO has the capacity, resources and experience to produce the results expected.

May 1, 2001

By Nelson C. White

This paper summarizes the present state and future prospects of the potash industry, with special reference to its impact on production in Saskatchewan.

Jan 1, 1968

By Hervé Toubon, Matthieu Davrinche, Jim Corman, Mamane Bello Boubacar Kinassa, Pierre Amadieu

Orano Mining maintains a significant level of Innovation and Development Research for its sites in Canada, Niger, Kazakhstan, Mongolia, and France. This effort is formalized within the six major thematic programs below, which include more than one hundred affiliated R&D projects:  Geological understanding, tools and methods for exploration  ISR technology (geology, modeling, mining development tools)  Mining technology (SABRE)  Ore treatment and processing (in particular via our Centre for Innovation for extractive metallurgy, CIME)  Environment (radiochemistry, modeling, tools and methods for remediation)  Digital Mine (sensors, transmission, database, and data modeling) This paper describes the main actions of these six programs, their stakes, and their progress. There is no single path leading to innovation but fostering an innovative context and a structured project approach are essential ingredients to successful development and industrial deployment. As a result, Orano Mining has, over the years, developed a disciplined methodology for R&D portfolio and project management. This methodology, presented here, targets a reduction in time to implementation while valuing both the expertise and the work in project mode.

Jan 1, 2020

By John H. McKillop

Industrial minerals production in Newfoundland in--creased in gross value by a total of 175 per cent during the ten-year period from 1954 to 1964. The Province accounts for all of ?Canada's fluorspar production and contains one of the most important fluorspar districts in North America. It is also the only producer of pyrophyllite in Canada, and quite recently has become an important producer of asbestos fibre. Limestone, gypsum, brick shale, sand and gravel also ?Contribute appreciably to the expanding industrial minerals phase of the Province's rapidly growing mining industry. Geological diversity characterizes Newfoundland's industrial minerals: Pyrophyllite deposits were formed by contact metamorphism of predominantly volcanic Proterozoic rocks. Fluorspar deposits are fissure-filling veins having the characteristics of typical epithermal deposits. Chrysotile asbestos production comes from one of the Island's serpentinized ultrabasic belts. Limestone is produced at three localities; two of them in the extensive carbonate rocks of the west coast. Gypsum production comes from a thick evaporite (gypsum and anhydrite) sequence in the Carboniferous rocks of the St. George's Bay area. Introduction

Jan 1, 1965

By J. Wickens

"Campbell Mine is dedicated to quality management in the form of a Continuous Improvement (CI) Operating Philosophy. This paper discusses that philosophy, why and how it is being implemented in the milling facility, and some of the challenges experienced to date. Examples of mill CI team projects and results are described. This paper describes practical experiences for those who are considering or are in the process of adopting a CI operating Philosophy.INTRODUCTIONCampbell Mine is 100% owned and operated by Placer Dome Canada Ltd. The mine is located in Balmertown, Ontario approximately 300 km northeast of Winnipeg, Manitoba. Campbell Mine has produced over s,000,000 ounces of gold since commencing operation in 1949. The operation is profitable and continues to be a major contributor to the gold production of Placer Dome Inc.At Campbell Mine, the concept of Continuous Improvement (CI) is being implemented to make further improvements to safety, quality, productivity, and subsequently profits. CI is not a ""program"". It is a way of doing business that concentrates on improving the system rather than finding fault and being resigned to the status quo.CI focuses on involving all employees in the decision making process and tapping their expertise to improve every facet of the business. In the past, many solutions were simple ""band-aid"" fixes treating the symptom, only to see the problem resurface again. With CI, solutions endeavour to address the root cause of problems and eliminate them permanently. Another primary goal is to eliminate unilateral decisions that benefit a small group but have a negative effect on the whole system."

Jan 1, 1995

In this study, flotation of fine galena, chalcopyrite and pyrite was performed after grinding with different extent of oxidation-reduction condition adjusted by grinding media. Sodium dithionite and iron ions were added in mill to simulate pulp potentials and iron oxidation species produced by grinding media, respectively. The types and quantities of the metal oxidation species on mineral surfaces were determined by EDTA extractions, while the surface electrical properties of minerals and interaction of different types of metal oxidation species were studied by zeta potential measurements. It was found that the nature and concentration of the absorbed metal oxidation species were dependent on oxidation atmosphere controlled by the iron amount of grinding media. These species interacted with each other and had an important role in determining flotation of fine galena and chalcopyrite as well as activation of fine pyrite by lead and copper.

Jan 1, 2006