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By J. B. Evans

"THE OPPORTUNITY to participate in a CIM seminarconcerning the direction of mining engineer trainingis perhaps fortuitous as it comes at a time when theengineering schools which have invited inspection byCanadian Accreditation Board of the Canadian Councilof Professional Engineers are examining theirrespective curricula.Currently there exists considerable soul-searching in various engineering schools across Canada where questions such as the following are being posed.- Have we achieved the correct balance between subjects related to technical methodology and subjects devoted to conceptual planning and design?- Should we include ""applied humanities"" in our program? (Whatever ""applied humanities"" might mean!)- Should courses covering pollution control, ecology, economics, technical writing, professional conduct and ethics be offered as compulsory subjects, as electives, or not at all?- Is it a better scheme to have students complete an Arts or Science degree before entering engineering?- Do we place too much emphasis on pure mathematics and sciences with the result that insufficient time is available for instruction in the engineering applications of these subjects?- Should English expression and/ or literature be included in the engineering programs and, if so, should these subjects be presented by the English department or by English lecturers captive to the engineering school? - Is the present program directed primarily at research activities rather than preparing engineers for their future roles in industry? - Should we teach our own versions of mathematics and physics? - Do we have sufficient engineers on the faculty strength or are we overloaded with Ph.D.'s from the pure sciences? - How flexible should the program be, what should the compulsory vs elective course content be, and what freedom of choice, if any, should be given with respect to elective courses? - To what extent should students contribute to faculty decisions?- How far should we pursue computer science subjects and do we need to make our students proficient in computer programming? - How far should operations research and mathematical models be carried in the undergraduate program when the students have limited experience in the real engineering world? - Realizing that an engineer never completes his education, should the undergraduate program cover ""bare bones"" engineering and should instruction in particular disciplines be left to graduate schools and / or industry?"

Jan 1, 1972

By K. Nagy

To support the implementation of its integrated SHEQ Policy, Cameco has undertaken an environmental leadership initiative with the goal of moving beyond regulatory compliance and significantly reducing environmental impacts in five key areas: air emissions, treated water quality and quantity, energy use and greenhouse gas emissions, and waste generation. To ensure environmental leadership becomes routine business practice, it was necessary to integrate the initiative into Cameco?s programs and management systems at the corporate and operational levels. Operations based environmental leadership strategies and action plans have since been developed, as well as a corporate reporting system to monitor Cameco?s environmental performance.

Aug 1, 2010

"In 2008, the Committee for Mineral Reserves and International Reporting Standards (CRIRSCO) and the Russian State Commission on Mineral Reserves (GKZ) entered into an agreement leading towards harmonization of Russian and international minerals reporting systems. The purpose of the protocol is to define an agreed method by which mineral resources and reserves, reported by companies in Russia according to the current Russian classification system, can be expressed in terms that are comparable to the CRIRSCO reporting codes in Russia and elsewhere."

Jan 1, 2003

By P. M. Chapman

Risks to aquatic receiving environments from uranium mining and milling fall into three categories: physical (habitat change), chemical (e.g., uranium, selenium, total dissolved solids [TDS], metals including vanadium), and radiological. Although all categories of risk need to be managed, chemical risks are the most significant and are typically chronic rather than acute. For instance, selenium toxicity is primarily manifested as reproductive impairment due to maternal transfer, resulting in embryotoxicity and teratogenicity in egg-laying vertebrates. Risk is best assessed using a weight of evidence approach focused on ecosystem services. Risk management should be based on both risk assessment and adaptive monitoring.

Aug 1, 2010

By Theophile Yameogo

Much has been said about the methodology of geomechanical design in underground excavations. However, the geological, hydrogeological and geotechnical complexities encountered at the production horizons in the Athabasca Basin commanded for a novel approach in the geomechanical assessment and design of underground openings. Rock mechanics engineers at Cameco McArthur River have been able to establish a practical methodology that goes beyond known conceptual approaches. In this paper, the author describes the original challenges and unique approach in the geomechanical assessment for drifts and chambers development. The example of the successful development of the 510-8225N Chamber will also be presented.

Aug 1, 2010

By Ward G. Wilson

Best practice in the design and construction of soil cover systems for mine waste management has advanced extensively over the past two decades. While significant progress has been achieved, we still have little experience with respect to proven performance for cover systems that must last hundreds of years. Some cover designs appear to be functioning well, while at the same time the performance of many more are now being called into question. This presentation evaluates the integrity of cover systems from both a global and local perspective in relation to the uranium industry within Canada.

Aug 1, 2010

By Theophile Yameogo

The rock mechanics literature has documented the challenges, failures and successes of tunneling through weak rocks. Cases usually deal with low RMR rock masses or high stresses in a fractured zone. With the combination of 5MPa water pressure, 14 RMR ground with clay infillings and ground freeze walls, the case of the 510-8225N development drift at McArthur River is certainly much more challenging, especially when high grade uranium production is at stake. The article explains the excavation and the ground control techniques that were used to overcome the challenges of development at the Unconformity in the Athabasca Basin.

Aug 1, 2010

By M. Oliazadeh

The bioleaching of fine low grade copper sulfide ore is described. A sample of ground (> 1 mm) copper ore from Sarcheshmeh, Iran, was subjected to a series of agglomeration procedures and subsequently leached. The best agglomerate was obtained by using lime and sulfuric acid as binders. A column bioleaching test of agglomerated ore was then run for 105 days along with a non-inoculated control column having thymol as bactericide. The results show that about 77.5% of copper was extracted in the bioleaching, whereas the control column achieved only 57% copper leaching.

Jan 1, 2007

By J. Kang

There is increasing demand to utilize aluminium alloy sheets and their spot welds by the automotive industry. While traditional uniaxial tensile tests only determine mechanical properties to small strain, direct measurement of the constitutive behaviour of aluminium alloy spot welds at large strain remains a challenge. A technique was successfully developed using digital image correlation coupled with shear tests to directly measure the constitutive behaviour of an AA6022-T4 spot weld to large strains. The results show that the spot welding process not only decreases the yield strength but also lowers the work hardening rate of the nugget versus the base material. Details of sample preparation, experimental approach and results will be discussed.

Jan 1, 2011

By John Battista

Uranium mining in Australia has a chequered history. This paper reviews the development of the Australian uranium mining industry from the 1930?s to the present day. It outlines the geology of the various deposits and the mining and metallurgical techniques used to extract the uranium. The industry is profoundly affected by government policies and the paper considers the roles of the Federal, State and local governments. The influence of public opinion on nuclear issues and the effects current and historical policies of various governments have had on uranium mining are outlined. Despite heavy restrictions placed on it, Australia?s uranium mining industry has maintained its place as one of the world?s largest producers. This paper also provides an outline of where the industry in Australia may be headed in future.

Aug 1, 2010

By Sergio Bustos

A significant expansion project is under way at KATCO?s Torkuduk In Situ Leaching (ISL) operation to increase uranium production up to about 4000 tU/year. Higher flows and lower uranium concentration are expected in the rich solutions coming from the well fields. Therefore, extra adsorption and elution columns and modified operating conditions are required to deal with the increased demand for uranium transfer from the ISL solutions to the eluate solution, which goes to the uranium precipitation section. Resin adsorption and elution performance have been interpreted and projected by using Mac Cabe-Thiele equilibrium diagrams. The resin load, the adsorption mass transfer coefficient, the adsorption zone height and the eluate concentration have been estimated for the expected changing operating conditions associated to the future mine plan. This information has allowed to improve the present operation results and to define the main process design criteria for the expansion project.

Aug 1, 2010

By C. L. Belyk

There are fifteen accepted types of uranium ore deposits and at least forty subtypes readily identified around the world. Each deposit type has a unique geological model which may also have unique processing implications. Primary uranium production in the past decade has come from a handful of these deposit types: unconformity, sandstone, calcrete, intrusive, breccia complex and volcanic. Processing implications for each of the fifteen deposit types can vary widely between and within different geological models. Some key characteristics of uranium deposits that may have processing implications include: ore grade, uranium and gangue mineralogy ? including clay and carbonate species and content, hardness, porosity, uranium mineral morphology, and carbon content. Processing roadblocks may occur as a result of one or more of these characteristics for any of the fifteen deposit types. Future technological advances and innovative thinking around uranium ore processing could provide avenues for roadblock removal setting the stage for additional and economically-viable uranium production from traditional and non-traditional uranium ore deposits.

Aug 1, 2010

By Kimberly Morrison

Strategically located within the Uravan Mineral Belt District of western Colorado, the Piñon Ridge Project is the first new uranium mill being proposed for construction in the United States in over 25 years. In 1992, dramatic changes to the US regulatory environment for uranium ore processing occurred making regulatory compliance an increased challenge for a new facility. Proposed as a 6.3 million tonne uranium milling operation, the mill will receive ore from a number of mines in the region. The project includes design and permitting of a uranium/vanadium processing facility, tailings cells, evaporation ponds, and ore stockpile pads. The focus of this paper is to provide an overview of the US regulations and how these regulations were applied to design of the mill facilities, as well as provide a status update on the project as the mill license application was submitted to the Colorado Department of Public Health and Environment (CDPHE) in November 2009.

Aug 1, 2010

By Z. Manafi

Bioleaching of a copper sulfide ore containing "activated pyrite", using a mixed culture of mesophilic bacteria, was studied. This type of copper ore had been found unsuitable for flotation because it produces a concentrate containing relatively high iron concentrations and, therefore, a low copper grade. Microscopic observations showed that pyrite particles had been activated by the formation of a thin film of chalcocite. Hence, a bioleaching process was considered as an alternative to treat this ore. Following shake flask and acid consumption tests, column tests of the crushed ore (75% -12.5 mm) were initiated and the effects of culture medium, agglomeration, and irrigation type on copper recovery were studied. The results showed that all the columns containing bacteria had copper recoveries around 90% compared to the abiotic control column with a recovery of 50%. It was concluded that bioleaching could be successfully utilized to process copper ores containing activated pyrite.

Jan 1, 2007

By L. Haavanlammi

The Outokumpu HydroCopper® process is a chloride based atmospheric leaching process alternative that can treat a variety of different concentrates. Chalcopyrite and other copper sulfides can effectively be leached under atmospheric pressure in strong, aggressive chloride solution using copper (II) ions as oxidant. Impurities are removed from the solution as carbonates and ion exchange. Copper is precipitated from the purified pregnant leach solution as copper (I) oxide, which is filtered and reduced by hydrogen gas to metallic copper powder, which is melted and cast into copper product. Sodium chloride solution from copper (I) oxide precipitation is decomposed in a chloralkali electrolyser, to products of which are circulated back to the process. The process has been designed for copper concentrates and is a fast and economical way to produce copper wire rod directly from concentrate. The process can efficiently handle impurities like arsenic and mercury, which can be harmful in the pyrometallurgical processes. The process has been tested in the laboratory and 1 ton/day demonstration plant scale and it has been proven to be commercially viable. The process has been designed to meet the strictest directives for emissions. Other environmental factors are carefully considered to obtain the highest possible eco-efficiency.

Jan 1, 2007

By A. Bhowmik

Uranium Refining is the process in which undesirable neutron absorbing elements such as Boron (B), Gadolinium (Gd), Cadmium (Cd), Europium (Eu), Samarium (Sm) and other heavy metals (Fe, Ni, Co, Ca, Mg etc.) are removed to make it nuclear pure. At present, Uranium refining is carried out by solvent extraction process by using organic based solvent e, g. TBP diluted with Kerosene. The above process generates lot of nitrate bearing liquid waste and degraded organic. In order to eliminate use of hazardous organic and ammonia for Uranium refining altogether, a new process has been developed. In the new process, Yellow Cake is dissolved in nitric acid and uranium peroxide hydrate is precipitated selectively from the solution leaving all the impurities in the solution by using commercial grade hydrogen peroxide at a pre-defined pH, U conc., temperature and stoichiometric quantity of hydrogen peroxide under mild agitation. The precipitate is filtered and washed with DM water to obtain nuclear pure product meeting purity standard as per ASTM C ? 753-99.The product is spray dried and calcined to obtain uranium oxide. The process eliminates use of organic, flammable, toxic chemicals, consumes less quantity of nitric acid and uses environfriendly chemical hydrogen peroxide. The process is simple and can be integrated in the mill. A patent application is entering national phase in several countries including CANADA and abstract/full paper is available in WIPO publication no: WO/2009/013759.

Aug 1, 2010

By Saeid Akhavan

Accumulative roll bonding (ARB) is a severe plastic deformation process for achieving ultrafine grains in metallic sheets without changing the sample dimensions. In this study, ARB process was carried out on 5083 aluminum alloy sheets up to 6 cycles. In this process, the surfaces of the strips to be joined are roughened and cleaned and then stacked. After stacking, the specimen is roll-bonded by rolling using a 50% reduction. The rolled specimen is cut into two halves, and the above-mentioned procedure is repeated for several times. Microstructural characterizations were analyzed by transmition electron microscopy (TEM). Tension and Vickers hardness tests were performed on produced sheets for evaluating their mechanical properties. In order to clarify the failure mode, fracture surfaces after tensile tests were observed by scanning electron microscopy (SEM). The results indicated that at the early stages of ARB process, grains were subdivided by deformation induced boundaries. After several ARB cycles, lamellar structure elongated in the rolling direction contains lamellar boundaries was formed. With increasing the strain, mean spacing of lamellar boundaries decreased. Finally, continuous recrystallization resulted in a microstructure covered with small recrystallized grains with an average diameter below 100 nm at the end of four cycle. The tensile strength and hardness of the 6 cycle ARB processed 5083 aluminum alloy sheet increased about two and three times of the initial values, respectively. Results indicated conformity between mechanical evolutions and microstructural changes during ARB process. Fracture surfaces observations showed that failure mode in ARB processed aluminum is shear ductile rupture with elongated small dimples.

Oct 1, 2011

By J. Donnelly, A. V. Deev

Substitution of coal and coke by renewable carbon (charcoal) is a low-risk and low-capital path to 50% or more reduction in net CO2 emissions by the steel industry. However, the high cost of charcoal and its low availability in most countries are barriers for the implementation of this approach. Development of an efficient wood carbonisation technology (slow pyrolysis) capable of producing large-volumes of charcoal from low-cost wood feed (e.g. wood wastes or forest residues) is an essential step towards the use of renewable carbon by the iron and steel industry. This paper provides a summary of the progress made over several years of R&D covering: (1) development and piloting of a new energy efficient slow pyrolysis process for production of charcoal from woody biomass at a competitive cost to the PCI coal, (2) techno-economic evaluation of the process. The main feature of the process is that the material undergoing pyrolysis is heated spontaneously without the supply of heat or air to the reactor. This makes it possible to carbonize large volumes of small-sized wood (e.g. wastes and residues) in a single reactor unit and capture high calorific value pyrolysis by-products

Jan 1, 2015

By Saeid Akhavan

Accumulative roll bonding (ARB) is a severe plastic deformation process for achieving ultrafine grains in metallic sheets without changing the sample dimensions. In this study, ARB process was carried out on 5083 aluminum alloy sheets up to 6 cycles. In this process, the surfaces of the strips to be joined are roughened and cleaned and then stacked. After stacking, the specimen is roll-bonded by rolling using a 50% reduction. The rolled specimen is cut into two halves, and the above-mentioned procedure is repeated for several times. Microstructural characterizations were analyzed by transmition electron microscopy (TEM). Tension and Vickers hardness tests were performed on produced sheets for evaluating their mechanical properties. Moreover the texture parameter of the ARB-ed samples was calculated using their XRD patterns and the related equation. Additionally, the texture evolution during the ARB process was demonstrate by analyzing the measured pole figures and orientation distribution functions (ODF) and skeleton lines. The results indicated that at the early stages of ARB process, grains were subdivided by deformation induced boundaries. After several ARB cycles continuous recrystallization resulted in a microstructure covered with small recrystallized grains with an average diameter below 100 nm at the end of four cycle. Texture analysis revealed fiber textures have been discovered with continiuose of the ARB process cupper. Brass, S and dillamor textures identify which their differences are in intensity of ARB process. Results indicated conformity between mechanical evolutions and texture evolutions during ARB process.

Oct 1, 2011

By E. M. De Souza

"A scientific testing program, sponsored by the Mining Industry Research Organization of Canada (MIROC), was undertaken on the surface and underground facilities of Inca's Crean Hill Mine to investigate the effectiveness of using dry drilling with a dust control system.The surface test work consisted of the monitoring of advance rates and bit life white a series of 165 mm holes, wet and dry, were drilled at both mine air (0.69MPa) and high pressure air (1.72MPa). The results, based on statistical evaluations of field data, indicated that penetration rates can be increased by an average of 24% when drilling dry with high air pressure and by approximately 27.5% when drilling dry with mine air as compared with wet drilling under the same conditions. Dry drilling also has the effect of reducing button wear by approximately 69% using high pressure air. The underground test work employed a dust collection system developed for use with large diameter holes (165 mm) and high pressure drilling. The testing program has indicated that an average increase in penetration rate of 35% can be achieved when dry drilling in rock (waste) and of 49% when dry drilling in ore with high air pressure. Although preliminary dust monitoring did not indicate any appreciable increase in dust concentration during dry drilling, further dust monitoring is still required.A comparative cost analysis has indicated the potential for reduction in drilling costs when dry drilling is utilized. Further testwork is to be conducted to develop a reliable dust collection system for underground production."

Jan 1, 1992