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By O. G. Olvera, D. G. Dixon, E. Asselin, L. S. Quiroz

Dissolution rates of chalcopyrite (CuFeS2) were calculated using electrochemical impedance spectroscopy (EIS). The calculated dissolution rate decreased by a factor of 3.2 after the electrode was passivated. The results presented in this work indicate that the reduction of Fe3+ was the rate-controlling step for fresh CuFeS2 electrodes while the transport of cations within the passive film limited the dissolution rate for the passivated electrode. The transfer of cations at the electrode/electrolyte and passive film/electrolyte interfaces did not affect the dissolution rates of the fresh and passivated CuFeS2 electrodes, respectively. The catalytic effect of pyrite (FeS2) on the dissolution of CuFeS2 continued after the passivating treatment. The contact of fresh and passivated CuFeS2 electrodes with different FeS2 particles resulted in increased dissolution rates, due to an increase in the reduction rate of Fe3+.

Jan 1, 2014

By Ian Thomson

OBJECTIVES OF EXPLORATION ? Prove/Disprove presence of potentially economic mineralization ? Keep on budget ? Minimize negative environmental impacts ? Gain a ?Social License to Operate? (SLO) WHAT IS A ?SLO? ? Granted by the local community ? Intangible, informal, non-permanent ? Has to be earned and then maintained ? Defined as ? Ongoing Approval (BSR and AccountAbility) ? Ongoing Approval, broad social Acceptance (Joyce and Thomson) ? Ongoing Acceptance (Nelson, and many others) ?Expression of the quality of a ?relationship?

May 1, 2010

By B. T. Lu, J. L. Luo, T. Yu, C. W. Chen

In this paper, the synergism in erosion-corrosion process occurring in oil sand wastewater transportation caused by the interaction of mechanical and electrochemical factors was experimentally investigated. The erosion-corrosion tests were conducted with A1045 steel in synthetic slurries comprising tap water and silica sand. The material loss due to corrosion-enhanced erosion was assessed with the chemo-mechanical model developed by the authors recently. The results indicate that the material loss produced by corrosion-enhanced erosion at the open circuit potential can be formulated as a linear function of logarithm of corrosion current density. The wastage caused by the erosion-enhanced corrosion was analyzed based on the concept of non-equilibrium thermodynamics. The material loss induced by the erosion-enhanced corrosion is approximately a linear function of overall erosion rate measured in synthetic slurries, indicating that erosion-enhanced corrosion could be reduced by adopting surface strengthening techniques to improve the resistance to the plastic deformation in surface layer.

Jan 1, 2004

By D. C. Fraser, W. J. Scott

"Airborne electromagnetic surveys were flown during 1965 in the Moose River area of Ontario. The systems used were INPUT Mark II and the Canadian Aero Otter. Anomalies indicated by both systems were located on the ground with vertical-loop EM. Two such anomalies were drilled, with no explanation being found in the bedrock geology. Subsequent seismic, resistivity and gravity surveys indicated that the sources of these anomalies lay in the overburden. Current work in the similar geological environment of the Winisk River area has shown that comparable AEM anomalies can still be misleading. The lesson to be, learned from these experiences is that additional geophysical work can help to resolve doubtful cases before drilling decisions are made."

Jan 1, 1973

By S. Balideh

A good understanding of the behavior of rock helps us to make more informed decisions regarding geo-structures. Engineers need accurate equations to calculate the strength and deformation of rock before and after failure. Previous studies explain the failure of rock to ultimate strength, and laboratory tests adequately determine the ultimate strength and deformation modulus of rock. However, there are few comprehensive equations to determine the post-failure strength and deformation of rock. Previous work shows that the post-failure behavior of rock depends on the behavior of the broken rock particles after failure. The following question is then posed: How can the post-failure behavior of rock be determined by the behavior of broken rock particles? In order to answer the question, this study pursues three objectives: (i) to explain the behavior of broken rock at low confining pressure; (ii) to estimate the behavior of broken rock via the extrapolation of scaled laboratory testing; and to suggest a procedure (iii) to outline the post-failure behavior of a rock mass at low confining pressure commensurate with the behavior of broken rock in a rock mass.

Aug 1, 2013

By D. L. Griffith

THE realization by metallurgists of the important effect that traces of impurity may have upon the properties of a metal, and their steady demand for purer and still purer metals, have made the special cools for 'trace' analysis of increasing value. In the United States at least, spectrographic analysis is becoming the standard method for determining the impurities in zinc die-casting alloys. The Hudson Bay Mining and Smelting Company, as a producer of virtually pure zinc, uses the spectrograph to control the purity of its products, and-as the electrolytic method is employed here-to control both the impurities in the electrolyte and those 'trace' elements, which, while they do not contaminate the zinc, have a great effect on the plating efficiency. The general plan of the laboratory is shown in Figure l; the housing for air purification, which is on the roof, is indicated by broken lines. One of the chief factors affecting the layout was the easy way in which a spectrographic assay can be spoiled by contamination. To minimize the quantity of dust tracked in, the laboratory was made separate from the general research laboratories, and an office was placed between the two. This arrangement has its drawback because of the traffic through the office, but it has effectively cut down dust. For similar reasons, the available space was subdivided into a number of small rooms, and the air currents in the laboratory were so arranged that dust would be carried where it would do least harm. Air is drawn in at the roof over a 50-kilowatt bank of Calrod heaters, through Annis air filters, by a No. 4 Sirocco fan. Most of it is forced into the spectrograph room, but some goes to the office and darkroom. The air flow is from the spectrograph room, through the plate-measuring room, into the chemical laboratory, where it is exhausted by a No. 1% Sirocco fan on the fume hood. Air can also re-circulate from the plate-measuring room back to the heater. The arrangement is such that the air in the laboratory is maintained at higher pressure than the outside air; consequently, no dirt enters through cracks about the windows and doors. A thermo-regulator holds the temperature constant within one or two degrees; only on the hottest days in summer does the temperature rise enough to affect the focus of the instrument.

Jan 1, 1940

By H. A. Wentworth

The Central Manitoba mining district, as spoken of in Manitoba, refers to that portion of the country lying between lake Winnipeg on the west and the Ontario boundary on the east, and from a few miles north of the Wanipigow (or Hole) river on the north, to a few miles south of the Bird river. It embraces two known mineralized belts; the gold area in the north, extending from the shores of lake Winnipeg almost to the Ontario boundary (in a slightly southeasterly direction) a zone some eight or ten miles wide and perhaps forty miles long, lying (for the most part) north, and parallel to, the Manigotagan river; and the Bird river copper and coppernickel deposits, an area not yet clearly defined, but in general lying immediately north of, and roughly parallel to, the Bird river. To the south of the Bird river is a somewhat differently mineralized area, numerous pegmatite dykes being found, with minerals typically associated with such rocks. More specifically, the known gold deposits are largely segregated in the above belt; (1) around English brook; (2) along the north shore of Wanipigow lake; the Rice lake area (about midway of the belt); and the Long Lake-Bulldog lake area, at the eastern end of the belt. Not all the known gold occurences are found in these segregations, but the density of claim staking in these areas is perhaps an indication of the greater number of prospects found in them to date.

Jan 1, 1925

By A. W. Jacob

THE shatter cut, or burn cut as it is often called, is one in which the centre of the round is almost reamed out by drilling holes so close together that the blasting of a few holes shatters the rock embraced by all of them. The idea of shattering the centre of a face by shooting holes drilled parallel to one another is not new. Some miners have used this method for years past, when drilling quartz or a face near timber. But, they followed the age-old practice of first blasting the cut, then the square-up. It was not thought possible to shoot both together. In the case of machine men, the two largest contributors to silicosis are dust from drilling and dust from blasting. It follows, then, that material reduction of exposure to either constitutes an important step in lessening the incidence o silicosis. It was? the hope of being able to do away with the necessity of the men having to return early to a face, through dust concentrations of 60,000 to 80,000 particles per cubic centimeter, that aroused interest "in the shatter cut at McIntyre. Efforts to this end were successful. Now, with this kind of cut, all holes of a round are shot simultaneously.

Jan 1, 1942

By B. Dubreuil, J. -M. Lalancette, D. Lemieux, C. Chouinard

The extraction of gold and silver has been examined via the use of mixed halogens: chlorine and bromine. The reaction was performed in a brine of sodium chloride with a small amount of sodium bromide at 40-50°C, in an atmosphere of chlorine, at atmospheric pressure. The process takes advantage of the very high reactivity of bromine towards gold, while the higher oxidation capacity of chlorine leads to gold chloride as end product with recycling of bromine. Fast reaction rates are observed along with gold recovery at the level of 95%. Chlorine-consuming common elements are removed prior to chlorination.

Jan 1, 2011

Innovation ? In economics a change must increase overall value, customer value, or producer value. ? Innovations are intended to make someone better off, and the succession of many innovations adds growth to the whole economy. ? Innovation may refer to both radical and incremental changes to either products, processes or services.

Feb 1, 2008

Accurate hematite solubility data are required to construct predictive solution chemistry models for complex hydrometallurgical solutions. These data are useful in understanding Fe(III) speciation and precipitation in a variety of hydrometallurgical processes. Hematite solubility data were generated in 10 to 70 g/L H2SO4 solutions and at temperatures from 130 to 270°C, using specially modified titanium autoclaves. These measurements represent an improvement over previous experimental data because of better in-situ filtration of the sample aliquots, the approach to equilibrium via hematite dissolution, and the inhibition of Fe(III) reduction on titanium surfaces. Fe(III) reduction was particularly studied to evaluate the inflationary effect of Fe(II) on hematite solubility measurements. Chromate was found to reliably inhibit Fe(III) reduction on titanium. Finally, the generated hematite solubility data were used to construct a solution chemistry model using the OLI software.

Jan 1, 2006

By Farzaneh Abedini, Narain Hariharan, Lucas C. McFarlane, Nikolas A. Romaniuk, Tiffany Thayne

The use of dewatered mine tailings as backfill material (commonly referred to as ‘paste’ backfill), is the most practiced form of backfill in Canada providing significant environmental benefits by reducing the size of external tailings facilities and improved economics through enhanced resource recovery. Paste backfill operations reuse filtered mine tailings with a cementitious binder and water to create a slurry that is hydraulically transported to refill underground stopes, later forming a structural network of cemented tailings in the mine stopes. Unlike typical structural applications that utilize General Use (GU) Portland cement; modern paste backfill operations maximize strength performance by blending Portland cement with ground granulated blast furnace slag (GGBFS) or other supplementary cementitious materials (SCMs). GGBFS and other SCMs offer key performance benefits and carbon reductions; however, the availability of these SCMs is rapidly dwindling in today’s carbon-constrained economy. This paper examines the development of an alternative binder system that provides similar performance and carbon reduction to that of GGBFS for mine backfill operations. The binder utilizes the chemical reaction between a reactive source of aluminosilicates and available calcium from calcium oxide or calcium hydroxide to replace between 50 to 100% of GGBFS. The performance of the binder is examined with insights into the hydration mechanisms that generate mechanical strength in the cemented paste network. Paste backfill slurries require precise engineering to create a material that maintains flowability during pipeline transport and generates enough strength to meet operational targets once placed in the stopes. Engineering of such slurries requires large amounts of water to be added to the binder-tailings matrix, far exceeding the typical water to binder ratios used in concrete mix designs. This characteristic of paste backfill warrants great emphasis on understanding the hydration mechanisms of the binder used in the paste backfill system. GU cement is typically composed of 50-70% tricalcium silicate and 15-30% dicalcium silicate.  The hydration mechanisms of these compounds consume 4 to 6 units of water to mineralize into calcium silicate hydrate cemented phases that result in compressive strength development. Cementitious aluminate and aluminosilicate phases make up 5-20% of GU cement and aid in secondary performance characteristics such as set time. Certain calcium aluminate hydrate phases such as monocarboaluminate and ettringite mineralize 10 to 32 units of water into their crystalline structure. Hydration products such as ettringite are traditionally avoided in construction applications due to their propensity for volumetric expansion after cement setting, leading to micro-fissures and subsequent strength degradation (known as ‘sulfate attack’). This paper proposes that such hydration products benefit the strength development in paste backfill slurries with the aforementioned characteristics due to their greater potential to mineralize free water. The newly developed calcium aluminosilicate binder is designed to replace 50-100% GGBFS or other SCMs used in paste backfill systems and meet operational strength requirements by providing exceptional hydration characteristics through cementitious reactions. Additionally, the aluminosilicates used have a minimal carbon footprint and a secure supply outlook, thereby allowing mine operators access to a low-carbon binder option throughout the mine’s lifespan.

May 4, 2025

By W. E. Cockfield

"The Last Chance claim is about 13 miles north of the village of Nicola and northeast of the city of Merritt; in the south-central part of British Columbia. It lies within Nicola mining division on the northern slope of Swakum mountain; near its summit. It may be reached by means of a branch road from the Kamloops-Merritt highway that leaves the highway at Nicola.The property was originally staked as a copper prospect by Oscar Schmidt in 1916. A number of cuts were driven and a test shipment of 22 tons of ore, averaging 4.6 per cent copper, was made from the surface showings. The property was then optioned to Granby Consolidated Mining, Smelting and Power Company, Limited, who did a small amount of drilling, after which the option was abandoned. The same year an option was secured by Northwestern Mines, Limited, of Spokane, and a SO-foot shaft was sunk. This option also was abandoned and after a number of years the property lapsed, but was re-staked in 1942 as a tungsten prospect along with other claims, and was drilled for the Metals Controller in 1943."

Jan 1, 1954

By Andrukaitis. E.

The increasing use of electronic equipment by the Canadian Forces has increased the importance of electric power. A power source that is packed with energy and yet light, small and durable is the common request of military users. However, this needs to be achieved while also addressing the requirements of safety, reliability and low temperature performance. The potential use of fuel cells in a military environment has become a possibility in several areas in the 21st century. Some examples of power source requirements and the materials related R&D required to give better, higher energy power systems in the future will be discussed.

Jan 1, 2005

By Hongpu Kang

The fully mechanized top coal caving mining method has been the main mining approach for thick coal seams with high output and efficiency in Chinese coal mines. The gateroads for the top coal caving mining faces should be driven along the floor of the thick coal seam with a part of the seam as roof. The support of the gateroads is commonly difficult because of the low strength and broken structures of the coal seams, and the increasingly large section of gateroads meeting the need of greater and greater face coal output. Based on the analyses on the geomechanics properties and production conditions of the top coal caving mining, the influences of the top coal caving mining parameters on the stability of gateroads, including mining thickness and face length, are studied. The deformation and damage features of the rock mass surrounding the gateroads with the top coal seam as roof are investigated, the interaction of the support with the surrounding rock mass, the support theory are studied. The bolting design method and criteria, bolting forms and parameters for the gateroads with the top coal as roof are put forward. The rock bolting components, including bolt bars, face plates, cable tendons, meshes, and steel straps, are introduced. Finally, the gateroad bolting effects are evaluated through a typical case study on the basis of field monitoring data, such as the displacement of surrounding rock mass and the forces along bolts and cables.

Aug 1, 2013

By J. Bourgeault

Modem civilization is indebted to that most ancient of the skilled crafts - the art of stone working, as the one consistent means whereby the dim un-recorded past has conveyed to our modem schools of science volumns of facts, written in characters of imperishable stone. Although left, centuries ago, to ruin and decay, architectural examples of the ancient building crafts still remain to the glory of the old master-builders, whose accomplishments in that remote age continue to influence and inspire their modem successors. Present-day architects and builders will leave to posterity just as faithful a record of our modes of living and of the methods now adopted for protection, as if it had been made by written word; and our craftsmen have profited greatly, in meeting modem requirements, by taking advantage of the indurance and utility of stone. Stone in all ages and stages of the world's civilization and development has been the material chosen by the masterbuilder, the one material possessing qualities that render it most desirable in affecting the artistic ideals of each period. It perfects the science of architecture through its durability and thus renders possible the study of man's workmanship in stone throughout periods of civilization of which we have no specific written account. Other materials have been used for the construction of man's habitations, but none have withstood the test of time, nor have established the credit of designer and builder so well as stone. _All other materials fall into ruin and decay, leaving neither mark nor monument for the enlightenment of mankind.

Jan 1, 1925

By L. M. Oshinowo

The incorporation of advanced analysis tools, such as CFD, into the process plant design process has become possible through advances in commercially available computational fluid dynamics software and faster computers. Multiphase modeling is now typically employed in the design phase of process plant design at Hatch. The multiphase models include Lagrange-Euler and Euler-Euler treatment of the multiple phases. Additionally, mixture models with interface-sharpening algorithms are applied to the prediction of free-surface flows in complex geometry. CFD is applied to applications where traditional design rules are not applicable. The additional rigor of CFD modeling in 2D and 3D allows process engineers to come closer to realizing true virtual plant design. The objective of this paper is to outline the benefits and pitfalls in the application of multiphase modeling for rigorous design. Several application examples in the hydrometallurgical field will be presented.

Jan 1, 2005

By S. H. Logan

The present discussions throughout the civilized world on the subject of gold for monetary purposes may seem due to general economic conditions during the past year. But for some years previously a small group of authorities had warned the world against the continued disregard of an equitable distribution of existing gold reserves, and had urged the necessity of keeping the supply of new gold equal to the monetary demand, which, according to world production and trade figures, increases on the average about 3 per cent per annum. In 1927, Sir John Aird, the President of The Canadian Bank of Commerce, stated that the United States could spare a billion dollars of the supply it then held, 4 ½ billion dollars. About a year and a half ago the Professor of Banking and Currency in the University of London, Mr. T. E. Gregory, said, "If the world finds it impossible to modify its habits so far as to make an organized effort to economize gold seem less Utopian, it must be prepared to pay for its bad habits, in this and other respects, by a possible loss of material welfare." These clear-cut statements were not heeded, perhaps for one reason because most countries were in the flush of prosperity, and making such great demands upon the mining fraternity for industrial materials as to distract attention, at least to some degree, from gold mining. Now the world knows it faces serious problems, first, of making? fully effective its present monetary reserves, which, although badly distributed, are as a whole ample for the needs of the present, and secondly, of preventing a shortage in the supply of new gold, one that may come within the next few years if the present sources of supply are not enlarged, and if there is no marked change in the technique of gold production.

Jan 1, 1931

By China University of Mining and Technology, P. Zhang, C. Zhou, C. Duan

"Recovering pyrite from the gangue with high sulfur content is of great significance for both economic development and environment protection in China. Due to the global water shortage and high cost in wet separation processes, it is urgent to explore more efficient energy and water conservation method in mineral processing field. This study has proposed an innovative method based on density difference for fine pyrite enrichment by vibration fluidized bed. In this study, the total sulfur content (TSC) of the gangue sample is 19.18%, and the pyrite is disseminated with fine granularity in the gangue which should be crushed for dissociation. The combination and dissociation experiment of -6mm gangue shows that the dominant density of -6+3mm, -3+1mm and -1+0.5mm comminuted material is +2.9g/cm3. Based on the analysis of characteristic, the effects of various factors on the separation performance were experimental studied. The results show that gas velocity, vibration intensity and bed height all have the significant effects. With the increases of superficial gas velocity, vibration intensity and bed height, the separation performance all presents a decreasing tendency. Additionally, the TSC of -6+3mm, -3+1mm and -1+0.5mm materials are respectively up to 37.94% , 35.43% and 30.61% at the optimum conditions, which are the 1.72?1.90 and 2.29 times as much as the TSC of raw material, respectively. This study demonstrates the vibrated fluidized bed can recovery pyrite from the gangue effectively.INTRODUCTIONWith the increasing mining and separation of coal, the yield of gangue has a further growth tendency, which has become one of the largest reserves of industrial waste (Querol et al., 2008). However, many harmful elements, such as S?NOx and Hg, is existed in the gangue leading the serious damage to the soil and environment (Hao, Yun, Zhanyuan, Sen, & Song, 2013). In addition, the economic would be suffered from the loss resulting in the occupied of arable land caused by the accumulation of gangue (Yeheyis, Shang, & Yanful, 2009; Zhou, Liu, Yan, Fang, & Wang, 2012). Therefore, the government has put forward the policies of ""green mining"" in China (Xing & Gao, 2009; R. Zhang, Ai, Zhou, Ju, & Zhang, 2015; Zheng, Du, Li, Qiu, & Yang, 2015). Among different research areas of coal utilization, extracting the useful minerals has become one of hot topics (Ledin & Pedersen, 1996; P. Patra & Natarajan, 2003; Partha Patra & Natarajan, 2004). At present, many researchers has devoted to the desulfurization of coal all over the world. As result, the sulfur element, which is mainly existed in the presence of pyrite, would transferred in the tailings, namely the gangue. Meanwhile, the pyrite is important raw materials to produce rubber, paper, textile and match. Consequently, recovering the pyrite from the gangue is not only suitable to the requirement of ""green mining"", but it could turn the waste into the treasure having the important significance."

Jan 1, 2016

By R. Roufail

Mineral exploration is in a race to employ drilling technology that can perform the exploration and drilling investigation in a fast and inexpensive manner. After an extensive study of the available drilling technologies in the market, coiled tubing was chosen as a tool to be employed for mineral exploration due to its flexible mobility and ease of operation with a minimum number of personnel. Since coiled tubing technology is primarily used in the oil and gas industry, it was important to re-design the coiled tube rig to drill hard rocks in a fast and feasible manner. The main requirements were to drill the smallest feasible hole diameter and go as deep in the ground as possible, in the shortest reasonable time. The drilled rock particles, cuttings, are to be collected and analysed at the surface for their metal mineral contents. The process also needs to be repeated multiple times at different locations for mapping, without the need to change the tube on the rig due to failure or potential failure. The focus of the new designed coiled tube, for drilling and mineral exploration, is three fold. First is to increase the rate of penetration in drilling by designing a small high speed turbo motor. Second is to determine the controlling parameters of cuttings transport to effectively lift the cuttings to the surface for analysis and third is to minimize the overall weight of the rig for manoeuvring and prolong the life span of the coiled tube string. In this paper, a small downhole turbo motor, 5cm outer diameter, is designed to achieve a rotation speed of up to 10,000 rpm to fit on a small bit, coiled tube drilling assembly. The motor design utilised multiple finite volume and finite element analysis softwares for fluid flow study and fluid structural interaction analysis. The paper is also introducing the concept of a flow slurry loop that is designed to lift the cutting particles to the surface for mineralisation analysis. The controlling parameters of the cuttings transportation are the particle?s physical properties such as size, density, concentration and shape, as well as the rheological properties of the carrying fluid, drilled hole angle, as well as the fluid flow rate and flow dynamics within the annulus gap between the coiled tube and drilled hole. Such parameters are addressed via experimental work as well as numerical analysis. The paper is also presenting the selection and testing procedure of the material type for the coiled tube string. The tube needs to be light in weight for overall rig weight and its transportability. The tube is also required to drill several dozens of investigation holes before failing due to fatigue. A fatigue bending machine is designed to test the endurance limit of candidate materials for coiled tube strings and a performance index methodology is followed for material selection of the optimum material. The coiled tube rig is designed to be light in weight for transportation and relocation. It is also required to speed the drilling operation with the minimum footprint and reclaim the drilled rock particles for mineral composition analysis at the surface.

Aug 1, 2013