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By B. Yu, Y. O. Oyediran, M. Robart

"This paper presents the latest flotation development testwork conducted in 2015 on the ‘B Zone’ samples from the Strange Lake Alkalic Complex (SLAC). Since the discovery by Iron Ore Company of Canada (IOC), metallurgical development has been under taken by a number of mining companies targeting various value metals, including yttrium, zirconium, niobium, and rare earths.Most recent, Quest Rare Minerals Ltd. (Quest) completed a Pre-Feasibility Study (PFS) in 2013 where the flowsheet was relatively complex and led Quest to explore alternative options. In 2014, the PFS flowsheet was simplified and one of the features introduced was pre-concentration by rougher flotation. The combined rougher flotation concentrate and slimes successfully recovered >90% TREE in 60% mass thus reducing capital cost and technical risks of the downstream hydrometallurgical processes. The latest flotation development testwork focused on achieving a pre-concentrate in which >80% TREE are recovered in 20% mass. Two separate reagent schemes, based on an ester phosphate collector (Clariant 1682) and a benzoylhydroxamic acid collector (Florrea 7510), were developed. Parameters evaluated in the development testwork included desliming, secondary yttrium and zircon collectors, depressants, temperature, conditioning temperature, time, and density, pH, sodium silicate type, cleaning, and flowsheet configuration. Both developed reagent schemes achieved the targeted metallurgy.INTRODUCTIONThe Strange Lake Alkalic Complex (SLAC) was discovered after geological survey and mapping studies by Geological Survey of Canada and Newfoundland and Labrador Department of Natural Resources between 1967 and 1980. Subsequent exploratory drilling programs by Iron Ore Company (IOC) in the 1980s found that the REE and high field strength element (HFSE) mineralization were within the central region of the SLAC which was named A Zone by IOC and later renamed Main Zone by Quest Rare Minerals Ltd. (Quest). Additional exploratory drilling outside the Main Zone by IOC and later by Quest, led to the discovery of B Zone, which was recognized as the most significant deposit of rare earth elements, yttrium, and zirconium in the SLAC. The B Zone Indicated Resources are estimated at 278.13 Mt at 0.93% total rare earth oxide (TREO) and Inferred Mineral Resources are estimated at 214.35 Mt at 0.85% TREO (Oyediran et al., 2014)."

Jan 1, 2016

By Xing-Liang Sun, Xian-Min Han, Zheng-Guo Zhu

The study on the material properties of frozen soils in China was being developed quickly in the past decades of years, because of the increase of the engineering constructed in frozen soil regions on the Qinghai–Tibet Plateau, and numerous research results were achieved mainly about strength and deformation behaviour and constitutive models of frozen soils. Studies have shown that the deformation procedure of frozen soils is irreversible; therefore, it is more appropriate to research mechanical properties of frozen soils by means of damage mechanics theory. In this paper, an elasto-viscoplastic anisotropic damage model is presented by introduction of Perzyna viscoplastic equation into analyzing the deformation of frozen soil. In addition, an anisotropic damage evolution equation is obtained by means of extending non-viscous damage to viscous damage. Triaxial tests at different strain rates are chosen to illustrate the application of this model, and good agreement between experimental data and numerically simulated results is obtained. The calculated results indicate that, under the same conditions, the damage at higher strain rate is less than that at low one. So the phenomena are explained from damage mechanics that the frozen soil has larger elastic modulus and shear strength at higher strain rates, and explained from mechanism that the emergence and development of micro-cracks in the body of frozen soil can be to some extent retarded at higher strain rates.

Jan 1, 2015

By D. B. Dreisinger, M. R. Tavakoli

"Vanadium has been produced from a variety of sources. This metal is known to make aqueous solutions of complex speciation as a function of vanadium concentration and pH. Considering the method of leaching, the impurities in the pregnant leach solution, and the planned vanadium product, different extractants and flowsheets can be applied for solution purification. This paper reviews the purification of vanadium leaching solution using organophosphorus, solvating, and amine extractants. This review focuses on vanadium separation from iron, molybdenum, and uranium, which are often present in vanadium resources such as primary ores, fly ashes, and spent catalysts.RÉSUMÉ Le vanadium est produit à partir de diverses sources. Ce métal est connu pour permettre des solutions aqueuses de spéciations complexes en fonction de la concentration du vanadium et du pH. En tenant compte de la méthode de lixiviation, des impuretés dans la solution mère de lixiviation et du produit de vanadium planifié, divers agents d’extraction et schémas de traitement peuvent être mis en oeuvre pour purifier la solution. Le présent article étudie la purification de la solution de lixiviation du vanadium au moyen d’extractants organophosphorés, solvants et aminés. L’étude cible la séparation du vanadium du fer, du molybdène et de l’uranium, lesquels sont souvent présents dans les ressources de vanadium telles que les minerais primaires, les cendres volantes et les catalyseurs usés."

Jan 1, 2016

By J. W. Senn

A magnesium alloy modeled after commercial alloy WE54 was thermomechanically processed and characterized to understand the mechanisms by which its texture can be randomized, as reported by Ball and Prangnell [1]. Samples were deformed in plane strain compression to prescribed strain levels at temperatures high enough to prevent cracking and then recrystallized. The deformation texture is very similar to that observed after plane strain compression (e.g., rolling) of other Mg alloys, such as common AZ31. However, the texture can radically evolve during recrystallization. Annealing above the precipitate solvus temperature results in a nearly random recrystallization texture where the initially strong basal texture is completely eliminated. Annealing below the solvus temperature produces a recrystallized texture similar to conventional Mg alloys, i.e., a weakened basal texture. If this same material is then annealed above the solvus to promote grain growth, a randomized texture evolves, which is similar that of samples simply recrystallized above the solvus. It is hypothesized that a sort of preferred growth mechanism, whereby grains with random orientation grow faster than those with the original basal texture, contributes significantly to the texture randomization observed in wrought magnesium alloys containing rare earth elements.

Jan 1, 2006

By Gerry Doeksen

The paper deals with three case studies: (a) the handling of wet concentrates (5 to 8 per cent moisture) through feed bins; (b) the handling of the same product in rail cars; and (c) the handling of dry concentrates (less than 0.5 per cent moisture) through feed bins. In each case, the paper discusses the problems of rat-holing. In each of cases (a) and (c), there is a discussion on the consequent extreme variations of feed rates coming from the feeders, making automation of process control difficult to impossible. Currently available bin-flow theory and flow property tests are used as aids in redesigning the bins. The paper concludes with illustrations of the final results after the redesigned hoppers were installed and tested. There is also a discussion on the advantages of the new mass-flow bins on adjacent feeder performance.

Jan 1, 1970

By A. O. Dufresne

A Step which, it is believed, will prove extremely beneficial to the Quebec asbestos-mining industry was taken during 1931, when the asbestos mine operators of the Province assembled to work out a uniform method of naming the products of their mines. The outcome of several meetings was the drawing-up of a classification which defined, limited, and designated anew the numerous grades of asbestos marketed. It entailed no drastic departure from the existing processes of grading, nor any revolutionary changes in methods of testing, but aimed rather to perfect existing methods. The classification proposed has been accepted by all operators in the Province, who, from January first of this year, began introducing the new nomenclature. Unless one is conversant with the properties and mode of occurrence of chrysotile asbestos, with the unique milling methods devised for its recovery, and with the history of the development of their technique, he may not readily understand the basis of the new classification. For information on these and other data concerning the industry, the reader is referred to a recent publication, Chrysotile Asbestos in (Canada, by James Gordon Ross, issued by the Mines. Branch of the Department of Mines, Ottawa. The object of this paper is to present briefly some of the phases in the evolution of the classification of Canadian chrysotile asbestos, in the hope that the recent effort to standardize the marketable products of one of Canada's most important non-metallic mineral industries will open a field for discussion, fruitful in new ideas and constructive suggestions. The necessity for the grading of asbestos results fundamentally from the fact that the price per ton depends on the length of fibre. At all times in the history of the industry, the very limited available supply of the longer grades, as well as the requirements of the trade, have caused relatively very high prices to be paid for fibre over half an inch in length, while for the shorter grades the price decreases rapidly, and at a rate which bears no proportionate relation to the length of fibre.

Jan 1, 1932

By Staff

One hundred thousand miles of flying over the North country without a single air casualty; much of it over virgin territory probably never before visited by white men; some of it over regions that abound with possibilities for minerals; all of it effective, for exploration and the establishment of bases and supply-stations, and for the carrying of men and their tools and provisions- this, briefly, is the record of Northern Aerial Minerals Exploration, Limited, a Canadian company organized Jess than nine months ago, which has been functioning, without interruption, during spring, summer, and now into winter. Our planes have ranged from the Alaskan boundary on the west to the Labrador coast on the east, and from the Transcontinental railway north to the Arctic circle. Our prospectors, carried on trips of hundreds, and occasionally thousands, of miles, have gone over large sections of country which were never before explored, and at the end of the prospecting season the Company finds itself in possession of several groups of important gold claims, which look most promising. In addition to this, we have been in contact with deposits of almost every known mineral.

Jan 1, 1929

By R. S. Adhikari

The changes in defects patterns or in element condition index during visual inspection of bridges are primary concerns for inspectors. This paper presents a new approach for change detection of defects in bridges by identifying changes in texture patterns through spectral analysis of digital images. The commonly used method for change detection is image differentiation. This subtraction method requires images to be of same size, scale, and rotation. However, no two images are same in real practices. Thus, image registration is required to align images and to produce change maps. This process is tedious and it is difficult often to achieve a good registered image. But, the change detection task can be readily modeled in frequency domain for texture patterns discrimination and also for quantifying their properties. This paper proposes a novel approach for change detection by transforming digital images into Fourier spectrum. In new coordinate system, 1-D signature functions can be drawn which facilitates easy comparison of textures in different directions. The proposed methodology provides useful tools for comparison of inspection history graphically and quantitatively. In practice, expensive sensors are used to detect subtle change in defect patterns. The proposed method can be used to detect any subtle change in defect patterns using digital images at much lower cost.

Aug 1, 2013

By P. H. Jennings

Commercial tellurium commonly contains heavy basemetal impurities such as lead, copper, iron, etc., as well as selenium and oxygen. The base metals may be removed by vacuum distillation or by zone melting. Vacuum distillation is a convenient method for treating moderate quantities (~ 100 kg.) for the production of a material having a total content of heavy metals in the 10-30 ppm range. By zone melting, it is possible to lower all the heavy metal impurities tm below the limits of spectrographie detection. Neither vacuum distillation nor zone melting is effective for the removal of selenium, but treatment of molten tellurium with hydrogen converts selenium to hydrogen selenide. This procedure is too s low to be considered except as an adjunct to zone melting. In the course of air-melting, many of the more easily oxidized impurities form a dross and may thus be readily removed. Substantial refinement with respect to iron, tin, chromium, aluminum, sodium, silicon, magnesium, calcium and manganese can be achieved in this way. Although tellurium can be electrodeposited from either acid or alkaline solutions of the dioxide, various factors militate against successful electro-refining, amongst which may be mentioned the brittleness of cast tellurium anodes and the tendency for the metal to be deposited in dendritic form, even at low current densities.

Feb 1, 1966

By P. H. Jennings, J. C. T. Farge

Commercial tellurium commonly contains heavy base-metal impurities such as lead, copper, iron, etc., as well as selenium and oxygen. The base metals may be removed by vacuum distillation or by zone melting. Vacuum distillation is a convenient method for treating moderate quantities ( 100 kg.) for the production of a material having a total content of heavy metals in the 10-30 ppm range. By zone melting, it is possible to lower all the heavy metal impurities tm below the limits of spectrographie detection. Neither vacuum distillation nor zone melting is effective for the removal of selenium, but treatment of molten tellurium with hydrogen converts selenium to hydrogen selenide. This procedure is too slow to be considered except as an adjunct to zone melting. In the course of air-melting, many of the more easily oxidized impurities form a dross and may thus be readily removed. Substantial refinement with respect to iron, tin, chromium, aluminum, sodium, silicon, magnesium, calcium and manganese can be achieved in this way. Although tellurium can be electrodeposited from either acid or alkaline solutions of the dioxide, various factors militate against successful electro-refining, amongst which may be mentioned the brittleness of cast tellurium anodes and the tendency for the metal to be deposited in dendritic form, even at low current densities.

Jan 1, 1966

By B. D. H. Knights, M. A. W. Bryson

Flotation of PGM ores, specifically UG-2, presents a number of technical challenges. These centre on the prevalence of chromite. Subject to over-grinding, chromite is primarily recovered to the flotation product through entrainment. This is of unique concern as it must be kept below a threshold for downstream smelting, with significant operational and monetary penalties being imposed should it exceed this concentration. A number of strategies have been developed to maximise PGM recovery in the presence of this unwanted contaminant. Specialised flowsheets form a vital basis and advanced control algorithms further enhance PGM recovery while minimising the recovery of chromite. Advances in Mineral Processing Science and Technology Proceedings of the 48th Annual Conference of Metallurgists of CIM Sudbury, Ontario, Canada Edited by

Jan 1, 2009

By D. Seo, P. Au, S. Yandt, N. Tsuno, A. Sato

Nickel-base single-crystal superalloys are used for gas turbine airfoil applications due to their excellent high temperature properties. A good understanding of the mechanical response of these alloys under different temperature and loading conditions is essential for modeling their behavior. In this study, the low cycle fatigue behavior of CMSX 2 oriented with the loading axis along [001] was investigated under zero-compression strain-controlled loading at 1100°C. The experiments were performed with or without a two-minute dwell (hold) in compression. The microstructure before and after testing was analyzed to understand the deformation characteristics including the effect of dwell.

Jan 1, 2010

By R. Neumann, O. Gomes, S. Gaydardzhiev

"Phosphorus in iron ores is considered as a deleterious component to iron making reflecting in cold shortness of the produced steel. The present study investigates the phosphorus migration pattern resulting from thermal treatment of an oolitic-type iron concentrate with and without additives. To this end focused mineralogical and microscopic observations were performed. The results have shown that roasting with alkaline additive drives phosphorus outside the hematite hosting mineral, however it remains evenly distributed inside the volume of the oolites. It penetrates inside the newly formed cementing phases of Al- Na-Si-Fe-type and also fills the interstices between the crystals. Other than phosphorus, aluminum, calcium and iron tend also to migrate towards the amorphous-type cementing phase. Finally, the possibilities for P removal by means of magnetic separation and acid leaching of the roasted concentrate were evaluated. The obtained final product presents a standard iron concentrate suitable for steelmaking with its phosphorous being dropped from 0.71% to 0.05% and iron grade of a nearly 66% being reached. INTRODUCTIONSignificant proven reserves of iron ores are still not exploitable due to lack of an economically viable and efficient technology for removal of phosphorus. Among them are the oolitic iron ores with high phosphorus which are estimated to nearly 377 billion tons (Hernandez et al., 2012). Phosphorus is a deleterious component giving a cold shortness to steel and often is penalized if exceeding 0.07%. Most of the high-P iron ores are considered refractory since phosphorus is finely disseminated and is evenly met as phosphate groups inclusions inside the limonite structure. Studies on inclusion of phosphorus in artificially synthesized goethite have shown that it is adsorbed as [HPO4]2- groups bridging the adjacent iron ions (Parfit et al., 1975). The high-phos iron ore originating from Lisakovsk deposit, Kazakhstan presents a similar mineralogical issue because the quantity of P, met as solid solution, is substantially higher than the one in P-containing minerals. A potential reason for that is the ore body formation process from the slow deposition of iron-rich precipitates together with clastic erosional sediments in rivers. There is significant quartz and clays inside and around the oolites. The deposit contains about 1.7 billion tons of measured and indicated reserves at 35–41% iron and 1.1 billion tons of inferred ore have been delineated possessing nearly the same chemical composition (Golubovskaya, 2003; Kokal et al., 2003)."

Jan 1, 2016

By Zhiwei Wang, Chunsheng Qiao

"Aiming at the problems of the existing calculation methods for the support pressures of shallow tunnels in layered jointed rock strata, by using OAT (orthogonal array testing strategy) and DEM (distinct element method), 12 influencing factors including the thickness of the weathered overburden, and the states of the rock joints were considered. Then, the classification of the loosening zone was analysized. On this basis, by using the DEA (data envelopment analysis) theory, quantitative analysis on the influencing factors was conducted. By analyzing the influence of the key factors, a prediction formula of the boundary of the ringent trumpet-shaped loosening zone was established. According to principles of stress transformation, the formula of support pressures of the loosening zone which could considering the key factors were deduced. Finally, a practical case was introduced and studied to verify the proposed method.INTRODUCTIONIn recent years, various urban subway tunnels are increasingly carried out through jointed rock strata in many cities. Rock masses are discontinuous mediums with fissures, fractures, joints, bedding planes, and faults. The frequency of joints, their orientation with respect to the engineering structures, and the roughness of the joint have a significant importance from the stability point of view. However, there is a lack of understanding about the influence of the joints on the stability of tunnels. Therefore, how to measure the degree of the joints’ influence is a problem that needs to be solved.For the calculation of the support pressures, until now, many research results were focused on soil ground (Bierbäumer 1913; Terzaghi, 1943; Peck, 1969; Sabatini et al., 1999). In terms of site tests and model indoor tests, by measuring strut loads and calculating earth pressure based on strut spacing, the results proposed by Peck (1969) and Tschebotarioff (1973) have been widely used in practice for designing excavation support systems under sand (drained) and clay (undrained) soil conditions. Note that, it is unclear whether these findings could be extended to rock strata. For numerical simulations, how to simulate the states of the rock joints is a key problem that needs to be solved."

Jan 1, 2015

By G. M. Hutt

Introduction The major development of industrial minerals in Manitoba has been in building materials. 'The building-stone industry is developed far beyond the needs of the Province, and the well known Tyndall limestone is marketed over a wide area throughout the other provinces to Canada. Similarly, gypsum and gypsum products are produced in excess of local requirements and are exported to adjacent provinces. The crushed-stone, sand and gravel, limestone, and lime industries are sufficiently developed to supply the needs of the Province and, notably in the case of lime and lime-stone, there is a surplus for export to the adjacent provinces and to the United States. The manufacture of common brick is well established, but for face-brick and other clay products the Province is dependent largely on importations. Production of silica-sand will increase as Canadian markets become available through recognition of the utility value of the Black Island sand as foundry-sand and for other purposes. There is some possibility of the export of feldspar, of lithium ore and concentrates, and perhaps of salt. A considerable part of the Province has not been seriously prospected for industrial minerals and it may be expected that, as time goes on, other deposits of non-metallic minerals will be discovered and opened up, especially as the prairie provinces become more industrialized. At the present time, there is some activity in the southern part of the Province based on gas and oil indications. Whatever may be the outcome of this work, it should yield valuable information concerning the geological structure of the area.

Jan 1, 1934

By Alex MacEachern

Air is the gaseous substance that envelopes the earth and forms its atmosphere. It is remarkable in the constancy of its composition; for while this is being continually changed as the result of the respiration of men and animals, and by addition of gases arising from organic changes and the products of combustion, it is ever being brought back to normal and the proper balance restored by the processes of plant and vegetable life. Nature sees to it that the air in which we live and breathe is kept purified. This does not apply to the air in a coal mine, where there are no natural forces to change and make use of the different gases formed or evolved, and where mechanical ventilation is the only effective means of keeping the air pure. The atmosphere consists of oxygen and nitrogen, not in the combined state but merely mixed. By volume, the composition is: oxygen, 21 percent, nitrogen, 79 percent, there being included with the latter small quantities of such substances as water vapour, carbon dioxide, nitric acid, ammonia, ozone, argon, neon, and organic gases. Of the two principal gases which form air, oxygen alone supports life. When air is inhaled into the lungs the oxygen is absorbed by the blood, which carries it through the body to nourish and energize it. Exhaled air consists of water vapour and about 4 per cent carbon dioxide, with from 16 1/2 to 17 per cent oxygen and 79 per cent nitrogen; the oxygen alone having been drawn on to any considerable extent.

Jan 1, 1930

By Mihaita Matei

An adaptive approach to control the deformation in tube hydroforming process is presented. This requires: the use of an existing non-linear FE software (ABAQUS) that incorporates a user material model (VUMAT), the development and implementation of an adaptive control strategy to coordinate the internal pressure and the axial load so as to prevent fracture and wrinkling failures (knowledge-base controller) and the application of the developed adaptive simulation approach for finding the optimal loading path required to hydroform a defect-free part with as uniform thickness distribution as possible (user's load subroutine (VDLOAD). In order to validate the approach, the case of conical hydroforming and the case of bending followed by hydroforming component is discussed.

Jan 1, 2011

By L. A. Wrigglesworth, A. S. Dadson

The orebodies of the Giant Yellow-knife mine occur in zones of schist, in an assemblage of typical Precambrian greenstones which form part of the Yellowknife Greenstone Belt. One of the most interesting problems at the mine concerns the fold-like attitudes assumed by the schist zones. The internal structure of the zones and orebodies provides much evidence of folding. A logical conclusion would be that the zones represent a single horizon which has been folded and drag-folded in the ordinary course of mountain building. However, surface mapping, and correlation of certain marker horizons, in underground work, indicate a homo-clinal succession of steeply dipping flows. If this concept of the geology is correct, the zones must cross-cut the regional strike at a small angle and, in the over-all aspect, the regional dip at a large angle. A mechanical interpretation of the zone structure is presented as a suggestion for the present until new evidence is found.

Jan 1, 1959

By L. Heber Cole

Introductory During the past few years, salt (sodium chloride) strata have been encountered in western Canada in a number of wells, while prospecting for oil and gas. The ever increasing number of such wells points to the presence of a vast salt basin, the boundaries of which are at present unknown. This basin extends in a northwesterly direction from a point near the United States boundary south of Regina, crosses the Saskatchewan- Alberta boundary northwest of Unity, Sask., and continues with more northerly trend to Waterways and beyond. The beds, as encountered, appear to have a general dip to the southwest of between 10 to 20 feet to the mile and a pitch along the strike to the southeast. Thus one finds the salt strata at Waterways, Alta., at 600 feet below the surface (121 feet above sea level) whereas at Radville, Sask. south of Regina, the top of the salt is at a depth of 6,643 feet below the surface (4,430 feet below sea level). Whether this is a continuous salt basin or a series of separate basins is not yet known. We do know however, that in some of the well~ more than one salt horizon occurs while in others which normally should have encountered corresponding beds, the salt strata are absent. This latter condition, however, may occur only in the southern part of Saskatchewan, where a barren area seems to come in from the southwest. In the northwestern part of the basin, on the other hand, the occurrence of the salt strata seems to be more regular and continuous, and depths at which salt should be encountered in a drill hole in this part of the basin may be predicted with a fair degree of accuracy.

Jan 1, 1948

By Erwin L. Zodrow

"IntroductionThrough an extensive coal sampling project in the Sydney coalfield of Nova Scotia during 1981 - 1984 involving a majority of the mineable coals (Zodrow, 1985, Fig. 1), a sizeable inventory on trace, minor and major metals was established. In this paper, results of studying the inventory are summarized, concentrating mainly on the relationship that exists between metal variations and thickness of coal channel samples (i.e. trends) and on explaining the trends in geochemical and sedimentological terms. As an over-all conclusion the Everglades peat of Florida is proposed as a modern-day analogue to Upper Carboniferous peat swamp development that took place in the Sydney Basin.Data InventoryFor this study 17 channel samples were cut , 8 cm to 14 cm channel width and 8 cm to 10 cm depth, from 10 successive coals which in stratigraphically descending order are as follows: Point Aconi (3), overrider Lloyd Cove (2), Lloyd Cove (2), Stubbart (2), Harbour (4), Backpit (I), Phalen (,I), Shoemaker (1) and McAulay (I), where bracketed values signify the number of channel samples cut from a seam (Zodrow, 1985, Fig. I). Each channel sample was subdivided by 15 em incremental length yielding a total sample size of 137 for analysis. By appropriate modern techniques these samples were analyzed to determine concentration levels for 32 chemical elements and ash content, the average results of which are presented in Table 1.Tests were also made for Pd, Pt, Ga, Nb, Cd, Cs, Sm and W but their concentration levels in many instances hovered on the lower detection limits that were used and on this accounts are excluded from discussion. Ashing, when necessary for the determination of concentration levels, was done for 12 hours at a temperature not exceeding 450°C. Concentration levels for the elements are reported in reference to whole-coal or whole-coal equivalents and discussed on this basis. In the course of the analyses, lower detection limits received careful attention."

Jan 1, 1986