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By Z. Tang

A collaborative project was performed between NRC Institute for Fuel Cell Innovation and MagPower Systems Inc, to develop a cost effective fabrication process to manufacture the anode for magnesium-air fuel cell with improved performance. A novel fabrication process was developed, which resulted in a porous microstructure with increased surface area, instead of the traditional solid structure. This porous anode greatly increased power density in the magnesium-air power source. This fabrication process is very simple and cost effective. Especially, this process makes it convenient to incorporate different alloying additions, as well as hydrogen inhibitor and electrolyte management additive into the anode. The anode composition was designed so that micro galvanic cells were formed as current is drawn out of the fuel cell, and resulting increased dissolution rate of Mg. It is feasible to incorporate hydrogen inhibitor and electrolyte management additive into the porous anode, and the anode with some kinds of inhibitors exhibited improved electrochemical performance. This paper describes the microstructure and electrochemical performance of anodes with designated porous structure and alloying additions. Furthermore, quantitative kinetics analysis of the obtained I-V curves and electrochemical impedance spectroscopy were carried out to clarify the mechanism.

Jan 1, 2005

The fracture behavior of second phase particles and the role of matrix material on the wear resistances of the three Al-Si alloys containing 8, 17, and 19% Si were investigated using single pass scratch testing technique by applying normal loads between 0,15 and 5,00 N, in ambient air, Optical microscopy and SEM with EDS were used to analyze microstructures and morphologies of scratch tracks of the Al-Si alloys, The results showed that needle-like Si particles fractured under a load of 0.50 N, while block-like Si particles fractured at loads above 3,00 N, The Al-17% Si alloy with large number of needle-like particles (area fraction 16,4%) exhibited the highest coefficient of friction (0,8) and the widest scratch track, The Al-19%Si alloy containing high Si percentage and larger number of block-like particles (area fraction 16%) exhibited the lowest coefficient of friction (0,37) and the narrowest scratch track width. Presence of block-like particles was effective in reducing the amount of material transfer from Al-Si alloy surfaces to the counterface.

Jan 1, 2005

By W M. Cameron

Geophysical studies have extended seaward in recent years, and the important discoveries which have been made have led to a better understanding of geological processes. A present source of certain minerals, the sea will eventually serve as an important source of desalinated water. The continental helves, in particular, represent a potential mineral resource. The expansion of Canadian oceanographic effort that is now underway will eventually lead to the exploitation of the wealth beneath the sea. THE subject of this symposium, which emphasizes the word "geophysics," the specialties of the speakers who are contributing and the nature of the audience at first made me believe that I, a a physical oceanographer, would be out of place. However, I shall undertake to classify myself as a geophysicist, and shall arrange my remarks on my specialty o that they might be of interest to those of you who are predominantly geologists, metallurgists or mining engineers.

Jan 1, 1963

By Stephen Hardcastle

Supplying ventilation in underground metal mines can be one of the most energy demanding services required to support production activities. Consequently, as energy, in the form of electricity or combustible fuels can be expensive and their unit cost is expected to increase, there is significant interest in reducing the overall demands of a mine?s ventilation system through such initiatives as controlling ventilation based upon demand and exploring other power alternatives to the current usage of the diesel engine in mobile mine vehicles. However, determining the benefit of any energy saving technology is complex and not universal applicable across the industry, consequently they have not been widely adopted. For these technologies to succeed they must be strategically applied based upon sound business cases. The intent of this paper is to provide information on some of the prospective control strategies and their potential impact on the power consumption related to supplying ventilation.

May 1, 2007

Phelps Dodge has recently operated a commercial scale, super fine grinding circuit of copper concentrates for use in a medium-temperature pressure leaching process. Two 355 kW vertical stirred mills were installed in series, targeting a grind of 80% passing 7.5 µm and 98% passing 15 µm as outlined in Phelps Dodge's concentrate leaching patent portfolio. This paper details the operation and results of the test program at Bag dad, as well as some of the operating challenges encountered.

Jan 1, 2007

By Hoeve. J.

"In the unconformity-type uranium deposit at Midwest Lake, mineralization is associated with extensive host rock alteration, which affects the metamorphic basement as well as the overlying Athabasca Group sandstones. Host rock alteration is manifested by (I) transformation of clay minerals [kaolinite into illite and chlorite (sudoile)]; (2) bleaching due to removal of hematite from the lateritic paleoweathering profile and the overlying red bed, Athabasca Group sandstones; (3) loss of coherence of the sandstone resulting from corrosion of quartz cement; and (4) in the immediate vicinity of high-grade ore, development of a clay envelope due to residual enrichment of clay minerals caused by massive dissolution of quartz. Clay mineral transformation and bleaching are the most prominent and the most widespread alteration effects, forming haloes that extend for several kilometres along the strike of the mineralized structure and also constitute distinct alteration pipes that rise f or several hundred metres above the unconformity to be truncated at the present top of the bedrock.Although the two haloes are largely congruent features, cross-culling relationship s indicate that clay mineral alteration represents an earlier phase in the history of the deposit than the large-scale bleaching that gave rise to the superimposed bleaching halo.Because clay mineral alteration and bleaching are intimately tied to the mineralization and extend well beyond the limits of the actual orebodies, host rock alteration may be used as an ore guide in exploration and drill-hole evaluation. In this application a third hydrothermal discharge centre was identified, as yet untested for are, which is located between the hydrothermal centres associated with the two known orebodies of the deposit.It is estimated that host rock alteration may enlarge a potential drill-target by a factor 10 - 20X. Information on the configuration of bleaching haloes can be obtained from systematic core logging, whereas diagnostic clay mineral alteration is readily identified by means of automated, quantitative XRD techniques."

Jan 1, 1984

By Dennis Z. F. Mraz

"Because rock salt and pot ash formations contain particles capable of elastic deformation, the material has usually been compared with various rheological models containing elastic elements. Extensive laboratory testing of salt and potash samples resulted in various theoretical conclusions based on conditions quite different from those in a deep mine. It is felt that sufficient data have now been collected from underground measurements and observations to demonstrate the inelastic behaviour of salt masses in a deep mine. The conditions in deep salt strata can be defined as near hydrostatic, because the acting pressures are very high compared to the negligible elastic limit of the salt. The pressure field and creep around the single opening is a function of its shape, size and age. The same factors, together with extraction, determine the behaviour of the mining a rea. The application of the correct analytical method in mine design can significantly improve the excavation techniques and predetermine the long-term behaviour of openings."

Jan 1, 1973

By V. A. James

The new electrolytic copper refinery situated at Copper Cliff, Ontario, has been in operation for over a year and a half. This plant is operated by the Ontario Refining Company, Limited. The associated companies behind the enterprise are the International Nickel ?company of Canada, Limited, the American Metals Company, Consolidated Mining and Smelting Company of Canada, Limited, and Ventures, Limited. The plant was an outgrowth of the rapid development of copper resources in the nickel-copper ores of the Frood and other great mines in the Sudbury district, and of the desire to have all primary production units grouped together as compactly as possible. Starting anode furnace operations in June, 1930, and electrolytic refining on July 1st of that year, after a record-breaking construction programme completed in only fifteen months, the plant soon settled into its stride and the usual starting-up difficulties were .rapidly overcome. The rated capacity of the plant, namely, twenty million pounds of refined copper per month, has, of course, never been reached, due to depressed business conditions and latterly to the world copper agreement limiting production. It may be said, however, that the present installation has proved its ability to produce in excess of its rated capacity, and with relatively minor additions to plant and equipment that capacity can be doubled. Owing to the severity of the winters, when temperatures of from 20 to 40 degrees below zero are to be expected, the building of this refinery involved a number of problems in insulation, layout, ventilation, etc., which were rather unusual in copper-refinery construction.

Jan 1, 1932

By S. K. Dimitrov

?Ellatzite Med? is one of the biggest mining companies in Bulgaria, processing about 12,000,000 t of ore per year. Waste materials left after extraction of copper concentrate are deposited in tailings dam ?Benkovski 2?. The hydraulic structure is built according to the downstream method, through hydrocyclonization where the downstream batter and the body of the wall are formed by the separated coarse sand particles of the separated tailings. In connection with the prolonged concession of Ellatzite Med and the enlarged capacity of Benkovski 2, the tailings dam has expanded on to the surrounding terrain. To guarantee a normal hydrocyclonization and build up of a tailings wall during waste deposition from the ore mill, the technological scheme of the hydraulic transport system of Benkovski 2 has been changed.

Aug 1, 2013

By T. K. Bose

According to the Intergovernmental Panel on Climate Change (IPCC), the average global temperature has risen over the last century. If this trend continues over the next century, the IPCC projects a significant increase in temperature and a rise in sea level. The changes in climate could adversely impact human health, agriculture, water resources and ecosystems. Most national and international agencies have concluded that our use of carbon-rich fuel is responsible for global warming through the greenhouse effect. In the future, the situation may get worse if the increased need for energy in countries like China, India and Brazil is fulfilled by burning fossil fuel. Advanced natural gas-fuelled vehicles have the potential to reduce carbon monoxide and reactive hydrocarbon emissions substantially compared to gasoline vehicles. Further environmental benefits can be realized by using a blend of natural gas and hydrogen. Such an approach will help create an infrastructure for an eventual transition to hydrogen.

Jan 1, 2005

By D. Furrer, M. Dallaire

The arrival of Image analysis in the last 20 years has changed the world of quantitative metallography. Many standard measurement techniques which were previously manual can now be done with fully automated systems. This reduces subjectivity and operator fatigue and therefore enhances the quality of the statistical results. In many laboratories, Titanium Alloy microstructures continue to be evaluated by traditional methods, where quality of results is subject to operator fatigue and level of experience. Advances in Camera technology have tremendously improved image acquisition. One can often see clearly at 500x what can not be observed at 1000x, allowing for a larger area to be analyzed, without the inconveniences associated with very high magnification objectives. Powerful and versatile Image analysis software combined with a high precision motorized stage gives access to a multitude of applications, which were extremely challenging or impossible until now. Image Analysis tools such as Multilayer Grab, which reconstructs an uneven image into one plane of focus (ex. Observation at high magnification of texture resulting from etching) and Mosaic which builds an image from a number of fields of view (ex. Reconstruction of very large grains at low magnifications) expand even further the power and flexibility of IA systems. This presentation will describe how automated methods are applied to the point count method and grain size measurement. We will show how cameras and software work together to permit quantitative measurements of primary alpha and prior beta microstructures, as well as lamellar alpha plate thickness in titanium alloys.Automated and semi automated quantitative measurements of various Titanium microstrures have been assessed, using the Clemex Vision PE. Examples of the methods and steps used are presented.

Jan 1, 2006

By D. H. Flather, J. W. Hendry, K. Drover

Black Hawk Mining Inc. has completed a comprehensive program on the prediction and management of acid rock drainage (ARD) at their Keystone Gold Mine (Keystone) near Lynn Lake, Manitoba. The program, initiated in 1994, followed a phased approach utilizing initial acid-base accounting (ABA) results and subsequent laboratory kinetic testwork to define site-specific sulphide oxidation and neutralization consumption rates in waste rock. Net acid generating waste rock at Keystone was defined through the kinetic testwork as waste rock yielding a net potential ratio (NPR) of less than two. A preliminary waste rock management program based on blending of potentially acid generating and acid neutralizing waste rock was advanced. Subsequent refinement of the management program followed the analysis of over 1580 ABA samples collected from individual blast holes during the initial bench development phase of the Keystone pit. Uncertainties in actually achieving adequate blending within the dumps at a mining- scale resulted in the development of a revised waste rock management program based on segregation. Recognizing that any successful management plan requires that the ARD characteristics of the waste rock be identified prior to in-pit blasting, the extensive ABA database was utilized to develop a rapid characterization scheme. By implementing a characterization scheme based on total sulphur concentrations and fizz rating, waste rock could be quickly segregated without delaying the natural flow of ore from the pit. Interestingly, it also became apparent that gold values were strongly correlated with total sulphur, such that traditional fire assays were supplanted with a simple and more cost-effective total sulphur determination. The program highlights the importance and benefits of collecting and exploiting data beyond that necessary to acquire appropriate development permits.

Jan 1, 2000

By J M. Gibbs

Craigmont Mines Limited mine 50,000 tons of ore and waste per day from the open pit at Merritt, British Columbia. An electric-powered "down-the-hole" drill, a diesel-powered rotary drill and two electric-powered rotary drills have been used. All primary drilling, as a result of cost and operating experience, is now performed with two electric-powered rotary drills. Trials with various loading techniques have increased the amount of AN-FO and decreased the amount of commercially prepared slurries used for primary blasting. Approximately 95 per cent of the primary blasting is accomplished with AN -FO, mixed at the hole. Introduction THE Craigmont mine is located near the village of Merritt, B.C., 240 miles northeast of Vancouver. The concentrator has been in production since September of 1961. Craigmont is a combined open-pit and underground operation. To date, slightly more than 95 per cent of the mill feed has been mined from the open pit. As underground development proceeds, the ore requirements from the open pit will decrease. The average milling rate from September, 1961, to April, 1964, was approximately 4,900 tons per day.

Jan 1, 1965

By R. Hans

Removal of toxic anions from aqueous solution was studied using a Magnetic Ion Exchange (MIEX) resin which is a polyacrylic, strong base resin. Gravity based settling is made more efficient due to the magnetic nature of the resin which is advantageous over conventional ion exchange resins. In addition, the magnetic microspheres of MIEX have larger surface area in comparison to conventional ion exchange resins. Over the years MIEX has been successfully used and has gained significant popularity for efficiently removing dissolved organic matter from wastewater and groundwater. In the present study the efficiency of the MIEX resin was tested for the removal of chromium(VI), molybdenium(VI), vanadium(V) and arsenic(V) anions. Effects of pH (2-10) and temperature (25oC-55oC) were examined. In general, low solution pH values were favorable for anion uptake by MIEX. Except for chromium(VI), the metal ion uptake was significantly increased by the increase in solution temperature. The adsorption data were analysed on the basis of chemical speciation and heterogeneous kinetic models.

Jan 1, 2014

By Duanyou Li, Qing Xiao, Zhiwang Wang, Xiaoqing Gan

"Seepage is a major cause of earth-rockfill dam failure. Numerical simulation of infiltration process, distribution of drift, flow velocity and direction after the impoundment can guide seepage control and evaluate its effects. A double field coupling model is established based on soil consolidation theory and the interaction between the seepage field and the temperature field. The simulation is implemented under the situation of core wall setted, core wall not setted, and core wall setted with concentrated leakage. The results indicated that the saturation line height was significantly reduced due to impervious core wall, and the temperature distribution is uniform above the saturation line. If concentrated leakage occurs, temperature distribution of dam was significantly changed, which is consistent with theoretical inference.INTRODUCTIONEngineering seepage field distribution must be calculated in seepage control design, optimization, and correction of new engineering construction of earth dams, as well as in seepage monitoring and evaluation of existing earth-rockfill dams. The aim of calculation is to identify the important parameters in seepage field, such as the coefficient of permeability, seepage flow, pressure, head, and allowable seepage slope, for effectively implementing seepage control design, correction, safety assessment, and anti-seepage reinforcement. These seepage parameters usually can be obtained by in-situ test and back-analysis based on reliable monitoring data.In order to obtain reliable monitoring data and reflect the earth-rockfill dam seepage state and change process, appropriate monitoring technology and monitoring method is necessary. The traditional seepage monitoring method is through site inspection and sensors (e.g., osmometer, piezometric tube and measuring weir) that buried in the structure and its foundation. However, there are still some disadvantages:"

Jan 1, 2015

By N. Geoffroy, E. Benguerel, G. P. Demopoulos

In the late 1990s, a chemical process to remove mercury and selenium from weak sulphuric acid solutions was patented and implemented in the CEZinc refinery in Valleyfield, Quebec. The CEZinc process comprises two stages. In the first one, sodium sulphide is added to the weak acid solution in order to precipitate the soluble mercury. The solution is then treated with sodium dithionite in order to reduce the selenium to elemental form. Because of recent changes in the composition of the industrial solution, a project to study the background chemical reactions was started. In this paper, a review of the background chemistry is presented on the basis of several eh-pH diagrams on one hand, while on the other experimental results are reported dealing with the reaction of selenium (IV) species with either dithionite, sulphide or a combination of the two. According to this work, elemental selenium enjoys a wide pH-eh range stability with selenium sulphide being metastable. Selenium (IV) in single metal synthetic solutions was found to be reduced - to elemental state - at ambient temperature down to ppb range with dithionite as long as the stoichiometric ratio (dithionite/selenium) was in excess of two and the pH < 1.7. Under these conditions the reaction was very fast reaching completion within one minute. Sodium sulphide proved equally effective in reducing selenium (this time as selenium sulphide) to ppb range from single metal solutions. However, in mixed Se-Hg solutions deviations from this "ideal" behaviour was observed resulting in higher levels of residual soluble selenium left in solution.

Jan 1, 2008

By E. A. G. Colls

PART I.-GASES IN INDUSTRY INTRODUCTION THE part played by gases in industry can be considered from at least four distinct viewpoints, viz: (1) As air to support combustion and life and do various kinds of work (2) As fuel, or as essential to certain chemical processes (3) As sources of danger from explosion or fire ( 4) As hazards to man&apos;s health The present paper deals with gases only insofar as they are sources of danger, or are hazards to health. It may be noted, however, that, in point of tonnage, air is one of the most important materials handled in any industrial plant. In the operations of the Consolidated Mining and Smelting Company, for example, 138,000 tons of air are handled daily, the only material exceeding this figure being water. The United States Bureau of Mines has listed no fewer than seventy-four gases and vapours that, under certain conditions, may be considered as ex-plosive or dangerous (poisonous). The commonest and most important of these are as follows : Carbon monoxide Methane Acetylene Hydrogen Oxygen Hydrogen sulphide Benzol vapour Ammonia Petroleum vapour Carbon disulphide Hydrochloric acid gas Cyanogen Carbon oxysulphide Chlorine ` Fluorine (and fluorides) Acetone vapour Acetic acid vapour Water gas Natural gas Gasoline vapour Coal gas Producer gas Ether vapour Nitrogen oxides

Jan 1, 1940

By Karl J. C. Harries

"4.1. INTRODUCTIONThis chapter, although divided into four parts, deals with only two principal topics. The first briefly describes and discusses some common types of property interests and considerations relating to them and the second deals with entering upon privately owned lands and obtaining the consent to do so.It should be noted that the terms “mining rights” and “mineral rights” are used interchangeably. As so used, they include the right to exploit the minerals and dispose of them for the benefit of the owner/lessee. This is relatively common in common law jurisdictions. In some jurisdictions, the two terms have distinct meanings, with “mining rights” referring to the right to work or exploit the minerals and “mineral rights” referring to the minerals themselves.Finally, it must be mentioned that the comments in the Introduction and §§ 4.2., 4.3. and 4.4. are based primarily upon Ontario law and Ontario’s mining and real property systems of registration. They have been included for illustrative purposes.4.2. LICENCES, CLAIMS, AND LEASESIn most jurisdictions, there are several basic types of interests that can be obtained from the state for mining purposes and that are of interest to the explorationist, as opposed to the operator. Different jurisdictions will have variations of these and possibly some extra ones that will address special purposes or local concerns. In virtually every jurisdiction, privately owned property rights are obtained through negotiation between owner and acquiror.Exploration or prospecting licence. This licence grants to the holder the right to prospect over a large tract of land and the exclusive right to acquire mining claims within that tract for the term of the licence. Such licences are usually negotiated documents requiring a minimum expenditure during the first year (often secured by a deposit or surety bond) and minimum annual expenditures thereafter to continue the licence in force up to its full term. The term will rarely exceed four years. The number of claims permitted to be staked will be limited in some way, possibly as to a maximum aggregate area or a maximum number of claims per annum. It is normal for the holder to have to drop part of the licensed area each year, so that the area shrinks annually, although exploration expenditure requirements will usually increase.These types of licences are usually used by governments to encourage exploration of otherwise unattractive or remote areas, such as the far northern parts of some of Canada’s provinces. They do not grant any real property interest in the area for which they are issued, and they will be subject to any claims or property rights that exist in the area. They are contracts with the state that grant certain exclusive rights in return for commitments to carry out work. They may or may not be specifically authorized by statute."

Jan 1, 2003

By M. B. Mansur, A. S. Guimarães, A. J. M. Santanilla, D. C. R. Espinosa, J. A. S. Tenório, R. A. Pini

The separation of Ni and Co from sulphate medium containing Mn, Mg, Cu and Ca was carried out by solvent extraction. The object of this study was to investigate the synergistic effect using phosphinic acid (Cyanex 272) and carboxylic acid (Versatic 10) and their mixtures in kerosene. The extraction percent of each metal ion was found to increase with increasing pH and extractant concentration. Co was preferentially extracted over Ni under the same extraction conditions. The separation factors of Ni/Co increased with the use of the synergistic systems investigated.

Jan 1, 2014

By R. D. Brown

Manitoba has now joined Ontario and Quebec in providing for new incentives and lower tax rates for the mining industry. A single rate of tax (to replace the former two-tier royalty), an investment tax credit and a relatively straightforward set of rules for calculating taxable mining profits are the main features of new mining tax legislation announced by Manitoba&apos;s Finance Minister Donald W. Craik in his May 15, 1979 budget address. On introducing amendments to reform The Metallic Minerals Royalty Act, the Finance Minister indicated that the new tax regime is intended to restore the Manitoba mining tax system to a competitive position in Canada, and should result in renewed investment in the province&apos;s mining industry. 1n this regard, the government could be right-there is little question that the new tax regime will produce greater incentives for the mining industry than the two-tier royalty system introduced by the New Democratic government in 1975. The proposed changes, contained in Bill 57, would largely be effective January I. 1979.

Jan 1, 1979