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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 I. Raheb, M. Y. Debili

"A set of Al-Co binary alloys (with respectively in weight percent 10%, 20%, 30%, 40%, 50% and 60% Co) have been studied by X-ray diffraction at the as compacted state. The structural evolution according to cobalt addition shows special features as the apparition of fcc cobalt and hcp cobalt beside aluminium in some cobalt compositions of the Al-Co mixtures using only cold compaction without sintering at high temperature. Figure 1 Cobalt is not a common alloying element in aluminium because its solubility is very low [1]. According to the pressure-temperature phase diagram, Co is known to exist in two allotropic forms: a low-temperature hcp phase and a high-temperature fcc phase [2-3]. At room temperature, Co is stable in the hcp form but it transforms to the fcc form when it is heated to above the transition temperature 695K. Powder aluminium and cobalt (99.999 %) were used in the proportions defined according to the required compositions. The total mass of the samples to be elaborated was between 8 g and 10 g. Cold compaction of mixed powder (Al-Co) under an uniaxial load of 10 MPa has been achieved to obtain a dense product (60%)."

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. 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 Z. D. Hora

Air hough diatomite is known in many parrs of British Columbia, deposirs of mineable size have only been found in the area between Kam/oops and Quesnel in the sourh-cenrral parr of rhe province. Ar Quesnel, commercial producrion has continued since 1950 from diatomite lenses up ro 35m rhick. OCCURRENCES of diatomite are reported from many parts of British Columbia, but deposits of mineable size are known only from the area between Kamloops and Quesnel. Only Quesnel deposits have yet reached the production stage. Commercial production dates back to 1950, and up until 1979 approximately 22,700 tonnes of diatomite had been produced. Most extracted diatomite was processed until 1980 by Crownite Industrial Minerals Limited in Quesnel to produce an oil absorbent and animal bedding. Smaller shipments are used to make insulating bricks on the lower mainland. Deposits near Quesnel extend 40 km along the western bank of the Fraser River from Quesnel to Alexandria; most production has come from Lots o. 6132 and 906. Di atomite is present as discontinuous lenses up to 35 m thick. Diatomite beds Industrial Minerals in Canada are of Upper Miocene age and are overlain by plateau basalts. Diatomite consists almost exclusively of Melosira granulara diatoms that are usually very small and mixed with variable amounts of clay, ilt and volcanic ash. In recent years, extensive beds of diatomite were identified near the confluence of the Chilcotin and Fraser rivers. Diatomite in this locale is a part o f the Upper Miocene to Pliocene Chilcotin Group of sedimentary rocks that are overlain by olivine basalt and related luffs. A deposit near Red Lake is situated 50 km northwest of Kamloops. Diatomite beds occur in the Tranquille Series of Eocene age and are similar in composition to those in the Quesnel area. The Red Lake deposit is abo ut 4 m thick but its areal extent is only a few tens of hectares.

Jan 1, 1984

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 M. J. MONEA

Canada's only economic high-swelling bentonite deposit is mined in Wilcox, Saskatchewan, by A vonlea Mineral Industries Limited. The bentonite resulted from devitrified and altered volcanic ash released during the Laramide Orogeny. Volcanic ash was deposited in a pre-Cretaceous basin that was formed by salt solution collapse structures. Sedimentary rocks in the Wilcox area belong to the Snakebite Member of the Upper Cretaceous Bearpaw Formation. Bentonite beds are 61 cm, 46 cm and 30 cm thick; these are separated by 365 cm and 182 cm of shale respectively. Saskatchewan bentonite is used primarily in the oil well industry.

Jan 1, 1984

By Bradley Stoughton

The magnetic oxide of iron, F eO4 , contains a theoretically larger amount of iron ( 72.4 per cent.) than any other commercial ore. It is probable that it has originated in many cases by the prolonged exposure of the hydrated oxide, ZF e20 a + 3H20 to heat and pressure which converts it first into hematite, F e20 3, and then into magnetite. It would thus appear as if nature had already done part of the work of removing all the oxygen and that magnetite should be relatively easy to reduce. That it is, in fact, less reducible than either limonite or hematite, is due chiefly to its dense and compact physical structure, which makes it less pervious to the furnace gases, and also to its characteristic action in resisting crushing to a uniform size, with consequent irregularity in reducing conditions within the furnace. The net result is that the magnetic oxide requires more fuel and more time for its reduction in the blast-furnace than any other iron ore of similar iron content and physical condition. There is another very important reason why the smelting of magnetite is more costly than that of hematite, and its treatment viewed with a great deal of adverse prejudice by blast furnace operators, namely, that magnetite decreases the proportion of heat developed by the fuel in the stack of the furnace, and increases the already excessive heat requirements of the heart.

Jan 1, 1924

By A. B. Irwin

Abstract The techniques used in recognizing, recording, and interpreting structures in the Slocan sedimentary ceries in the West Kootenay district of B.C. are presented here in the hope that they will be of use to others working in complexly folded areas. The general pattern of folding in the Central Slocan area is obscured by lack of outcrop over a large part of the country, lack of marker horizons, local complexities of folding, and several systems of faulting. 1t was found necessary to observe and record in great detail all primary and secondary structural features and to analyse those observations on a statistical basis. The determination of bedding tops as well as bedding attitudes proved to be of fundamental importance in determining the pattern of folding. The interpretation of secondary linear and planar structures confirm:; this pattern. Accordingly, the thickness of the Slocan sedimentary series is computed to be several times that formerly postulated. Introduction The data upon which this paper is based were collected largely during the field seasons of 1947 and 1948 when the writer was employed by the British Columbia Department of Mines on detailed mapping in the Slocan mining camp. Additional observations were made by the writer during 1950 when engaged in property examinations for the Geological Survey of Canada. This presentation is largely a condensation of part of a more comprehensive thesis (5) and is restricted to observations and conclusions pertaining to the mapping of complex folds, stripped of any hypothetical discussion. Except for some unique occurrences of primary structures, there are no features or techniques described here which are not presented in standard textbooks on structural geology. It is felt that the major contribution of this paper is the method used in applying these standard techniques to a specific field problem and in interpreting the results.

Jan 1, 1951

By S. C. Ells

Introduction An investigation of the bituminous sands of Alberta was begun by the Mines Branch, Department of Mines, in 1913. This investigation was interrupted during the period 1916-19, but was resumed in 1920. Work completed in October 1924 has included detailed topographical surveys of extensive areas, examination and sampling of principal outcrops, the mining of trial shipments, laying of demonstration pavements, and a study of methods adapted to the recovery of hydrocarbons from the crude bituminous sand. Bituminous sand consists, for the most part, of clear quartz grains, cemented together by petroleum residuum or bitumen. In form the quartz grains are most irregular, varying from sharply angular to smooth, waterworn shapes. The bitumen has a specific gravity of 1.018 and has a penetration of 9.00 mm. (77° F. 100 grams 1 sec.). The percentage of bitumen associated with the sand varies from 5 to 25 per cent. A large tonnage is available in which the percentage of bitqmen is 15 per cent or over. Production Up to the present time, production has been restricted to requirements for experimental .and demonstration work. The total quantity shipped for such purposes has not exceeded 750 tons.

Jan 1, 1925

By Victor F. Hollister

Although none of the deposits discovered to date are of commercial interest, significant Frasch or sedimentary sulphur deposits occur in Nova Scotia in Upper Mississippian Windsor Group evaporites. The evaporite sequence contains anyhdrite and is overlain by impervious shales. It also is •mderlain by locally petrolijerous formations that are potential hydrocarbon sources for reaction with anhydrite to produce sulphur. As well, stratigraphic and structural traps are known to exist in the Mississippian beds. Thus, all requisites for sedimentary sulphur genesis are present. Available hydrocarbon sources are numerous but small; resultant sulphur deposits therefore are probably also small. Evidence suggests, however, that sulphur deposition is not yet complete.

Jan 1, 1984

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

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 R. R. Irrinki

Abstract -The Key Anacon deposit consists of four sulfide zones called, from south to north : Key Anacon No. 1, Key Anacon No. 2, Key Anacon No. 3, and Key Anacon Copper Zone. Massive sulfides of zones 1, 2, and 3 are underlain by rocks correlated with the Nepisiguit Falls Formation and are overlain by matie volcanic rocks correlative with the Boucher Brook Formation. In contrast to zones 1, 2, and 3, narrow northwesterly-trend.ing, copper-rich fracture zones occur within the Patrick Brook Formation. Sulfides in zone 2 occur as three mineralogical associations, namely: pyrite-chalcopyrite, pyrite-sphalerite-galerta, and pyrrhotite-sphalerite-galerta. The distribution of lithologies and en-echelon patterns of the three sulfide lenses of Key Anacon No. 2 zone are the result of F1 and F2 folding. Zone 2 is the most promising economically, with proven reserves of 1.11 million tonnes grading 0.2207o Cu, 3.47% Pb, 8.41% Zn, and 96 g/t Ag; the zone is open below a depth of 427 m.

Jan 1, 1992

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 Deborah McCombe

"and Bill Roscoe, Consulting Geologist and Principal with Scott Wilson Roscoe Postle AssociatesMineral property valuations are carried out for a variety of reasons, such as mergers and acquisitions, non-arm’s length transactions, initial public offerings of stocks, support of audited financial statements, fairness opinions, determination of vendor considerations, litigation, expropriation, income tax matters and insurance claims.The CIMVal Committee was formed in 1999 to review and advise on approaches to the valuation of mineral properties. CIMVal is a special committee of CIM formed on the recommendation of the Mining Standards Task Force of the Toronto Stock Exchange and the Ontario Securities Commission.After solicitation of views and consultation with various interested parties, the CIMVal Draft Standards and Guidelines for Valuation of Mineral Properties were released for comment in February 2002 and were finalized in February 2003. CIMVal’s objective was for the standards to be used by the mining industry in general and to be adopted by Canadian securities regulators and Canadian stock exchanges. To that end, the standards contain many of the definitions and concepts of National Instrument 43-101, Standards of Disclosure for Mineral Projects, which came into force in February 2001.The intent of the CIMVal Standards and Guidelines is that mineral property valuations be carried out by appropriately qualified individuals and that all relevant information be fully disclosed. It consists of two parts: standards, which are mandatory in the valuation of mineral properties, and guidelines, which elaborate on the standards and provide guidance and recommendations for the valuation process and for reporting."

Jan 1, 2003

By Raj Thamburaj

"Over the last few decades, the emphasis on affordability and reduced cost of ownership has necessitated the development of innovative processes to carry out repairs in aero engine components. Conventional weld and braze repairs have evolved into advanced, sophisticated processes using state of the art knowledge in lasers, robotics and materials technology. This paper illustrates past and present scenarios in an attempt to illustrate progress that has been made in this area. The problems encountered in the past have been detailed along with the solutions that have been developed and commercially implemented to address these issues. Apart from technical progress, this presentation also addresses the progress made in business approaches and in Certification/Regulatory issues surrounding aero engine repair. Progress in Technology Repair technologies have also been the embryo from which new and revolutionary manufacturing technologies have evolved as well. Electron Beam Free Forming and LENS are examples of how a completely new manufacturing concept can evolve what was originally only a process to join metals. The current and future potential of these spin offs is discussed providing examples of application. While several problems have been solved over time with the implementation of advanced repair technologies, the demands of the industry have created new challenges. The paper describes these issues, outlines potential solutions and discusses the future of repair technologies in terms of the far reaching influence it is sure to have in design, manufacturing, maintenance management and life extension. Progress in Business Trends.Business approaches to repair and maintenance have also gone through considerable change with the introduction of ""Power by the Hour"" and other similar arrangements between the companies responsible for engine overhaul and the end-users. Program Based Logistics (PBL) is yet another innovation to provide a win-win situation for the repair service provider and the end user. This paper traces the development of these business initiatives and highlights successful applications. Progress in Repair Certification, Regulatory Issues.Understanding of the issues surrounding certification of repairs has also evolved with time and regulatory issues have been clarified considerably. Procedures for analysis and testing are much clearer and ""Check Lists"" are being drafted for certifying repairs on various engine components. The PMA phenomenon has added yet another dimension to the issues regarding certification and these are discussed as well."

Jan 1, 2010

By F. Mackay, S. A. B. da Fontoura

"The theoretical solution for a viscoelastic well was presented by Gnirk and Johnson in 1964. From this an exercise was executed to validate the numerical simulation of a cemented salt well. The exercise comprised the geomechanical behavior through time of a cemented salt well, this was achieved using a finite element commercial software. This simulation showed the accuracy of the theoretical solution for viscoelastic materials such as salt rock. The theoretical solution presented elastic and viscoelastic analytic equations for the tangential and radial stresses. The equations for the elastic material (casing and cement) and for the viscoelastic material (salt rock) are presented here: Where equations 1a & 1b are the radial and tangential stresses of the elastic material; equations 2a & 2b are the radial and tangential stresses of the viscoelastic material; and a, r and b are the geometrical parameters explained in Figure 1. These equations are function of Pb, a stress time dependent factor that comes from the Burgers model of viscoelasticity. This is well explained in Gnirk and Johnson (1964) and for the sake of simplicity is not disclosed here. Po is the stress at section A-A’ dependent of the depth h."

Jan 1, 2015

By A. B. Rossetti

"THE MISSION TO Offshore Scotland was in my opinion a very worthwhile venture, as it indicated the scope of the offshore oil and gas business and how we might exploit it to the fullest here in Nova Scotia - if our offshore fields eventually become producing fields. The writer was able to attend a considerable number of lectures and as a result gained some valuable know-how on the engineering design, financing and operation of the North Sea oil industry. There are many new fields of technology that had to be developed to overcome the North Sea's hostile environment and a great deal of the same technology will have to be developed to win oil and gas from our continental shelf. The visit left me with several impressions, which in the main are:(1) The high order of investment required to develop offshore oil. The investment ranges from 10 to 20 times that required for a similar output on land. Each barrel of oil costs on the average of about $2,- 500 per barrel per day.(2) Because of the high investments required, before the first oil is produced the field must be brought into production at the earliest possible date and initial lead time from decision to production is less than four years. In the British Petroleum field, working at a depth of 450 feet will require an investment of $900,000,000 to develop a production of 400,000 bbl per day. (3) The size and complexity of equipment required is beyond anything ever imagined. Problems which must be overcome are such factors as water depth, wind velocities, wave height, wave period, long periods of darkness, low temperatures, distance from land, and fog."

Jan 1, 1973

By Warnett Kennedy

"GENUINE CONCERN for the environment is a built-in attitude of mind. If you do not have it by age 40 you probably never will. Some people speak the jargon of 'environment' and 'ecology' for political reasons, others because it feeds their need and bias toward attitudes of moral indignation or dissent. Others pay lip-service for purely business reasons. Complete reactionaries equate conservationists, ecologists and environmentalists as either 'commies' or 'pinkos'. Their real credo is the old saying, ""Where there's muck there's brass."" Those who have genuine concern for good environment are not only romantics like Thoreau but realists who sense the danger to our planet if human greed is rampant and unchallenged. The cities are in real trouble. Almost 75 per cent of the population already live in and around cities. Even mining men live in cities or bring up their children in the new 'instant' towns. The ecology of cities is the concern of all. Our distinguished guest Stewart Udall, in his book ""The-Quiet Crisis,"" quoted Thoreau in 1859 as having written ""each town should have a miniature wilderness park, a primitive forest of five hundred or a thousand acres where a stick should never be cut for fuel, a common possession forever."" Mr. Udall will be glad to know that this advice was taken in at least one instance known to me. I refer to Stanley Park in Vancouver. It is a primitive forest of 1000 acres right inside our small downtown peninsula. It remains unmanicured. This month we celebrated the completion of a seawall of 4%, miles along its perimeter. The construction of this wonderful walkway started in 1910. We are very, very proud of our park."

Jan 1, 1972