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Recently, renewed interest in the recovery of uranium from leach solutions has necessitated a re-examination of the hydrometallurgy methods used for uranium in the 1960?s to 1970?s. A synthesizing overview of the lessons learned in those decades together with examination of recent developments in this area is warranted. This paper considers uranium recovery chemistry from acid and alkali leach solutions using solvent extraction and resin ion exchange, and provides information on circuit selection and configuration, equipment selection and design, as well as operational considerations. The unique thermodynamics of uranium solvent extraction are also presented and discussed.

Aug 1, 2010

By J. Koike

Mg alloys for structural application have attracted much attention. However, high process cost and poor mechanical reliability are major concerns upon expanding the application to a wider area. In order to break through these barriers, better ductility is desired at lower temperature. Plastic anisotropy and peculiar twin formation appear to play key roles in the deformation and fracture mechanisms of Mg alloys. In the paper, dislocation slip and twin formation are reviewed. The effects of crystallographic texture and grain size are discussed. The results suggest that a good control of microstructure and texture can improve ductility and mechanical reliability of Mg alloys.

Jan 1, 2006

By R. A. S Villegas

The Brazilian government announced in 2007 its plans to reactivate the nuclear program. As a result of this decision, a new nuclear power plant is already being built and there are studies dealing with, among other activities, the building of 4 to 8 new ones until the end of 2030. Such increase on the country?s uranium demand affects INB, the Brazilian state company that?s in charge of uranium supply. This paper describes scenarios predicted to the Brazilian nuclear industry for the next years and the INB plans to meet the country?s needs in terms of uranium exploration and production.

Aug 1, 2010

CI, Data and Data Systems Road Analysis Control Quick and simple manual Analysis Case study Visual relation of analysis

May 1, 2013

By Normand Bédard

This presentation highlights Cambior?s initial approach for recruiting and retaining its international employees, the importance of proper preparation and the support needed to ensure a competent and stable workforce. In general, most of the training and information available for human resources personnel prepares the specialist for handling various aspects of labour relations, recruitment and hiring, benefits administration, employee relocation, etc. This is usually done in a Canadian context. Only recently, has more specialized training been developed to prepare human resources practitioners for the complex issues related to expatriate employees and dealing with human resources issues in other countries.

May 1, 2003

By K. Fujita, T. Kikuchi, Y. Sakamoto

Ceramic fibers were classified as a category 2 carcinogen by The European U legislation. Therefore we developed non-fibrous insulating castable which utilizes n porous aggregate, which is composed of Calciumhexaluminate. Although at beginning we applied alumina cement as binder for non-fibrous insulating castable, kind of formulation had a poor resistance to spalling. We developed non-fibrous insulating castable without alumina cement. This solved a problem which pre\ formulation had a poor resistance of spalling. We applied a new non-fibrous insub castable for reheat furnace in steelworks, then we could achieve good result which condition equivalent to ceramic fiber insulating castable.

Jan 1, 2004

By P. W. Waggitt

ABSTRACT From approximately 1986 until 2000, uranium production was at a historic low. In 2003, uranium mineral exploration surged, despite the global financial crisis; however, the shortage and aging of qualified and experienced operators and regulators might soon become a constraint to this upsurge. This is true for all types of engineers, geologists, other scientists, tradespeople, and technicians. The situation raises questions about how the global mining industry in general and the uranium sector in particular will cope with future staffing needs. In this paper, the author examines the current situation and describes how some organizations are seeking possible solutions.

Jan 1, 2014

By M. Rigaud, K. Sankaranarayanane, X. Zhou

The effect of varying fine alumina/ultra-fine alumina ratio on the Bingham to dilatancy transition in alumina based, self-flowing refractory castables has been studied in detail employing rheological tests and particle size distribution measurements. Analysis of flow resistance and torque viscosity values has shown that Bingham to dilatancy transition is strongly influenced by fine alumina/ultra-fine alumina ratio in the castable, as well as by the nature of ultra-fine alumina. The calculated values of rheological constants and the viscosity coefficient were found to increase at higher fine alumina/ultra-fine alumina ratios.

Jan 1, 2004

By Shamil Shaikhutdinov

CO adsorption on gold particles deposited on well-ordered alumina and various iron oxide films has been studied with temperature programmed desorption (TPD) and infrared reflection adsorption spectroscopy (IRAS). Structural characterization has been performed with scanning tunneling microscopy. Data show that the CO adsorption exhibits a size effect in that small particles adsorb CO more strongly. The effect generally vanishes after annealing to 500 K. For annealed samples, CO TPD and IRAS spectra are nearly independent of the particle size and supports studied. The results indicate that the CO interaction with gold surfaces is essentially similar and involves low coordinated atoms.

Oct 1, 2003

By David S. Robertson

"IntroductionCanada has been one of the world's leading producers of uranium since atomic energy first became of practical importance in 1942. Indeed, prior to this time, between 1933 and 1940, Canada produced significant amounts of pitchblende, as a source of radium, from the Eldorado Mine at Great Bear Lake*.Uranium was first reported in Canada, however, in the middle of the 19th Century in the vicinity of Theano Point on Lake Superior north of Sault Ste. Marie. In the early 1900s, uranium-bearing minerals were reported in Quebec north of the St. Lawrence River and in pegmatites in Quebec and eastern Ontario. In 1930, G.A. LaBine and E.C. St. Paul visited an occurrence of cobalt reported by the Geological Survey of Canada in 1900, and brought the Eldorado Mine into production in 1933, as noted above, producing, in the main, silver and pitchblende.In 1942, developments in atomic energy were such that the Government of Canada, at the behest of Great Britain and the United States, requested that Eldorado, which had been closed in 1940, be re-opened to produce uranium for the Manhattan Project. In September, 1943, all discoveries of radioactive minerals were reserved to the Crown and their staking by private interests was banned. In January, 1944, the government nationalized Eldorado and formed a Crown corporation, the present Eldorado Nuclear Limited, to take over the assets. That year marked the formal beginning of uranium exploration in Canada.The Period 1944 to 1948In 1944, the Crown Corporation and the Geological Survey of Canada began exploring for uranium deposits, largely in the areas of Great Bear Lake and Lake Athabasca. In that year, A. W. Joliffe of the Survey visited properties on the north shore of Lake Athabasca near Beaverlodge Lake and recommended that Eldorado acquire claims in the area. In 1946, P. St. Louis and E. Laurum, prospectors working for Eldorado, found the pitchblende veinlets that led to the Ace Mine. Shaft sinking began in 1951, and production, through a carbonate leach plant, began in 1953.Continuing drilling on the Eldorado claims led to the Verna ore bodies, some 6,000 feet northeast of Ace, on which shaft sinking started in 1954."

Jan 1, 1986

By I. H. Redeker

North Carolina is the leading state in the USA in feldspar, mica, and spodumene production. Mixed feldspar, spodumene, mica and quartz are mined from hard rock, open pit deposits and recovered by flotation from the fresh pegmatite type ores. Potash feldspar, mica, clay and quartz are recovered from weathered decomposed pegmatites. The North Carolina State University has a Minerals Research Laboratory in Asheville with trained personnel and flexible pilot plant equipment. The flowsheets for the feldspar, spodumene and mica producing companies and for large phosphate and glass sand flotation plants were developed and tested in Asheville. Examples and problems of pegmatite flotation are demonstrated with flowsheets and slides.

Jan 1, 1981

By C. F. Gleeson

"I HAVE BEEN ASSIGNED the pleasant task of adding a last word in way of summary to this session. I think that the trend set in having a geochemical session at the CIM Annual General Meeting is a good one and I hope it will continue so that members of the mining fraternity can get together on a regular basis and discuss geochemical problems peculiar to our Canadian scene. A series of interesting papers have been presented on what has been considered by many in the past as not only a problem area for geochemistry but even an impossible one. The papers should help dispel some of these fears. Lack of development of geochemical techniques in the Shield has been due to a variety of factors, many of which have been mentioned. However, I feel that one of the main reasons for this lack of development has been timidness on behalf of many people to get out and do the necessary work which helps produce answers to many of the questions asked. New developments and applications of geochemical methods in the Shield will not be done by the faint of heart but by those who have the curiosity, interest, imagination, drive, resources and, most of all, the intestinal fortitude to stick to it and not give up because results or conditions do not meet with preconceived notions. Another element that will be needed by those who will successfully apply the techniques and who will be responsible for new breakthroughs is the systematic approach to sampling and analysis and the integration of geochemical, geological and geophysical results. Erratic sampling patterns - a sample here and a sample there - generally lead to more problems than solutions."

Jan 1, 1971

By Robert J. McCarthy

Many technologies have been adopted over the last half century for the haulage of material from open pit mining operations. Some of the technologies utilized include rail, off-highway trucks, conveyors, and slurry pipelines - each having its unique application and benefits. Over time, truck haulage has become the primary means of surface mine material movement, though recently it has been plagued by problems of tire shortages, high diesel fuel costs, labour shortages, and carbon emissions. This paper focuses on In-Pit Crushing and Conveying (IPCC) as a competitor to truck haulage which has the potential to solve many of these problems. An overview of the available technology is presented along with measures required to overcome perceptional if not physical barriers to implementing this technology in modern open pit mines.

May 1, 2011

By Ross Dimmock

The productivity of a mine has the same goals as the quest to complete a tunnel project both safely and within time. A key aspect to achieving this goal is to excavate and support the working face as quickly as possible, allowing early re-entry to start construction of the next advance in safety. As with tunnels, the use of high performance wet-mix sprayed concrete has increased in mines dramatically over the last few years, and year on year has seen a stepwise increase in shotcrete performance, particularly in the first few hours. Shotcrete early age strength development clearly offers mining teams enormous advantages by allowing early, safe re-entry to the face. This paper illustrates that in the hard rock tunnelling field, modern shotcrete approaches do not cause delays in re-entry, but allow a continuous construction cycle. Furthermore, the paper identifies the most suitable, up-to-date shotcrete admixture and equipment technology available to the mining community to permit early re-entry.

May 1, 2003

By Chris Ryan

Operational excellence along with the need for a capital management strategy demanded an educated budgetary retirement age for haulage fleets, with uniform applicability. Given fleet size and volume of data for the Komatsu 830E fleet within Teck, this unit type was selected for development of a retirement age model suitable for all operations. The model is designed to act as a capital planning and fleet management tool aimed at minimizing costs. Life cycle parameters were examined to facilitate a visual and numerical representation of a fleet over a period of time. Physical availability and operating cost models were developed to obtain an understanding of the life cycle. These models became the drivers behind the fleet-wide retirement model. A wide analysis range of the equipment life cycle was used as it assured that the optimum retirement regime would be accurately captured. Average annual spend, including cost of operating and ownership was measured against the corresponding retirement age. Targeting the minimum within this range yielded the optimal retirement age.

May 1, 2010

By E. Marcotte

"Technology developments and improvements are imperative to maintain a viable mineral processing industry. In order to achieve optimum implementation of technology in processing plants, safety conscious and efficient work forces are required. Effective management methods are required to prevent employee injuries, equipment or environmental damage and process losses. Good leadership also provides for employees to perform their work in the safest and most efficient manners to attain optimum recoveries of the valuable minerals and produce high quality mill products. Equipment and processes must be designed, operated and maintained as required to assure safe and efficient mineral processing.INTRODUCTIONThe Canadian mining industry must contend with many challenges to attain and maintain a competitive position in today's global market. Canadian Mineral Processors play a vital role in meeting the challenges and achieving optimum mineral productivity.Ongoing technology developments and improvements continue to be imperative to maintain a viable mineral processing industry. The efficient implementation of technology developments requires a safety conscious, skillful and productive work force.In addition to technical and human resources, challenges may also include governments, labour unions or environmental advocates who at times may appear to be misguided or unrealistic. Canadian Mineral Processors must not allow themselves to be overwhelmed by these apparent obstacles but must use their demonstrated ingenuity to achieve successful solutions.It should be recognized that the majority of the Canadian work force are, in fact, a potentially talented and skillful people with ambitions to excel. As leaders of people, we must provide the methodology, incentive and direction that will allow our work forces to realize their ambitions. If the potentials of our work forces are not recognized and leadership is not properly exercised much loss will occur. That is, safe effective and efficient work will not be achieved."

Jan 1, 1993

By Angeles Mendoza Sammet

Based on the analysis of issues associated to conflicts between communities and mining companies in Mexico, this paper suggests actions to make mining more sustainable in Mexico. Interviews with key informants and a revision of documental information available on the internet provided information on 15 cases of conflicts in various parts of the country. The issues varied from incompliance with environmental law to assassination of community members opposing mining. The analysis concludes that mining is not sustainable in Mexico. Both mining companies and the Government of Mexico can make changes to improve sustainability. Mining companies could take a proactive approach and engage in consultation with communities before starting operations. Sharing information with communities on environmental management programs and monitoring results can be a way to start building trust and demonstrate environmental commitments. Companies can implement and evaluate CSR policies to ensure that all staff and contractors are trained on them to reduce and/or prevent corruption and violations of human and indigenous rights. Only 3 of the 15 companies had clear social responsibility policies or sustainability targets, but no reports evaluating them. Complying with the law does not make a project sustainable because of corruption, deficient enforcement, and gaps in legislation. The Government of Mexico should address the following points to make mining more consistent with sustainable development. Update the mining legislation to introduce sustainable development principles and consultation. Incorporate the notion of Free, Prior, Informed Consent (FPIC) for Indigenous People (IP) on all applicable Mexican laws or regulations. The government should not grant concessions on protected areas or indigenous lands without extensive meaningful consultation with the public, IP and land owners. Finally, it is vital to increase SEMARNAT?s capacity to review impact assessment reports and inspect and monitor environmental compliance along the life cycle of projects.

Aug 1, 2013

By Mike Power

Geophysical techniques have played a pivotal role in northern kimberlite exploration since the initial discovery at Point Lake in 1991. In the Slave Craton and surrounding regions, there are definite contrasts in physical properties between kimberlite intrusions and surrounding bedrock. Kimberlite commonly displays higher magnetic susceptibility, distinctive remnant magnetism, low electrical resistivity and lower density than surrounding rocks. In addition, the distinctive geometry of kimberlite pipes is reflected in geophysical responses which further facilitates target discrimination. There has been an evolution in geophysical exploration strategies over the past 12 years. Helicopter total magnetic field and electromagnetic (HEM) surveys have proven to the most cost-effective means of conducting first pass investigations in prospective areas. During the early 1990's, total magnetic field and frequency domain electromagnetic surveys were virtually the sole techniques employed during follow-up surveys. Inevitably, the initially high rates of kimberlite discovery declined in the areas surrounding the original finds. Marginal magnetic and EM anomalies were all that remained to be tested and this spurred interest in the improvement of existing interpretation algorithms and in the application of additional complementary techniques to reduce the exploration risk. Gravity has become a popular third survey following the deployment of the Falcon (TM) airborne gravity gradiometer system by BHP Billiton in 1999 and improvements in ground techniques. Ground penetrating radar (GPR) has proven to be particularly useful in delineating kimberlite pipes following drill discovery and in exploring for kimberlite dykes in settings where indicator mineral trains indicate such targets are likely. Seismic methods have been tested for both reconnaissance and delineation but remain underemployed. Given the high cost of drilling in the North and the proven success of geophysical techniques in reducing exploration risk, it is likely that an increasingly diverse range of geophysical techniques and innovative interpretation techniques will continue to be applied in kimberlite exploration.

May 1, 2003

RISKGATE is an interactive online risk management system developed by the Minerals Industry Safety and Health Centre (MISHC; University of Queensland) to assist the mining industry in implementing continual improvement in management of major unwanted events, and so maximising health and safety performance. A comprehensive body of knowledge has been compiled from diverse mining industry experts for risk management of tyres, collisions, fires, isolation, strata underground, ground control open cut, explosions, explosives, manual tasks and slips/trips/falls. This paper presents an overview of the body of knowledge captured from diverse mining industry experts for the management of unwanted strata incidents, and explosions in the underground environment. This knowledge is divided into a series of initiating events within both topics (as listed) with further degrees of classification based on design, operation, and management concerns. Strata Underground Initiating Events: Explosions Initiating Events Loss of strata control at longwall face Fire or ignition in a sealed area Loss of strata control in outbye roadways Fire or ignition in an unsealed goaf area Loss of strata control in roadways under development Fire or ignition in an extraction face Loss of control of overburden and caving behavior Fire or ignition in outbye Loss of pillar system stability Loss of control of goaf edge in pillar extraction Fire or ignition in a development panel or first working Loss of strata control in shafts The system guides the user in generating substantive and leading edge controls to assist industry stakeholders in the design, management and reporting of organisational and regulatory compliance requirements. From a broader industry perspective, RISKGATE provides an environment for knowledge capture and knowledge exchange to drive innovation and best practice in the identification, assessment and management of risk. By capturing operational knowledge from industry experts, RISKGATE provides a cumulative corporate memory at a time of high personnel turnover in the coal industry.

Aug 1, 2013

By S. Caron, M. Bourassa, J. Châteauneuf, L. Tardif

"Since many years, the Yvan-Vézina gold plant custom mills and processes different ore types that show different behaviors. Because of this, cyanidation control is more complex than for a typical milling operation. In 1992, a Cyancor™ on-line « free cyanide » analyzer has been installed for monitoring and optimizing cyanidation. This implementation significantly reduced cyanide consumption for the overall cyanidation process. In order to further reduce cyanide costs, an automatic control strategy has been implemented to decrease fluctuations of« free cyanide » from their set points.This paper outlines the major steps of the project: process control audit, control strategy development, implementation and running-in period. Control strategy features include data filtering modules, adaptive PID algorithm and set points management modules are also presented. Finally, the strategy efficiency is illustrated with load-disturbance responses.IntroductionLocated in northwestern Quebec, the Yvan-Vézina plant has an average capacity of 1300 t/d using carbon-in-pulp technology. In 1991, the Yvan-Vézina gold plant was processing three types of ores (Beauchemin, Mouska and Silidor mines) and a pyrite concentrate (Beliveau mine). A cyanide reduction program was then undertaken to reduce « free cyanide» fluctuations <6>. To reach this objective, the optimum cyanide concentration was determined for each ore, a continuous monitoring method with the Cyancor™ on-line analyzer was developed and a tighter control of cyanide addition was applied. These modifications to the leaching practice significantly reduced cyanide consumption.After a while, it was observed that regulation of « free cyanide » concentrations could still be improved by the use of an automatic control strategy. Yvan-Vézina and CRM began collaborating in 1995 to develop and implement such a strategy. Results show that main disturbances of the circuit (e.g. ore mineralogy and pulp feed rate) can be significantly overcome in order to reduce their effects on the leaching operation."

Jan 1, 1998