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By F. T. Mooney

Introduction The Flin Flon mine of the Hudson Bay Mining and Smelting Company, Limited, is on the interprovincial boundary between Manitoba and Saskatchewan, about four hundred miles north of the Canada-United States boundary. The orebodies are gold, silver, zinc, and copper replacement deposits occurring as irregular lenses of massive sulphides, arranged en echelon, and irregular masses of disseminated copper sulphides in chlorite. The country rocks are of Precambrian age, dominantly lava flows. Development of the Mine The mine is opened by two vertical main shafts- the North Main and South Main shafts- 3,800 feet apart. The North Main shaft has a depth of 2,210 feet and the South Main shaft is completed for stoping operations to the 3,250-foot level (see Figure 1). These shafts are connected by main haulages driven, on the footwall side of the orebodies, at 520-foot intervals down to the 2,210-foot level. No. 3 (subsidiary) shaft is on the footwall side of the orebodies at a point between the North Main and South Main shafts, 2,400 feet south of the former. It has a depth of 3,250 feet and connects with all main haulage levels- with both Main shafts down to the 2,210-foot level and with the South Main shaft on the 2,750-, 3,000-, and 3,250-foot levels. Other openings tO the mine include B North fan raise, the opening due to the recovery of the open pit sill pillar, and several back-fill raises.

Jan 1, 1949

By G. S. Ospanova

The results of complex processing sulphide copper ore and advantages of recovery of copper by vat and heap leaching, sorption, cementation and electrolytic solutions processing and utilization of waste material after heap leaching of copper for production of building materials were investigated. The combined chemical solvents with the additives of oxidizing agents are developed at the KazNTU. The solvents are inorganic or organic chemical reagents, which form complexes of Cu, Au, Ag, Pt, Ni, Sr, Co etc. Recovery of non-ferrous metals from solutions and purification of industrial waste waters is carried out on the base of using new synthetic and natural sorbents (from local raw materials) which are able to bind ions in both cationic and anionic forms depending on type of ligands and external conditions. Optimum parameters of copper sorption were determined. The developed wasteless technologies of copper extraction from sulphide ores with usage of new non-toxic solvents and accessible sorbents with full recycling of water are tested in pilot scale heap leaching, and are recommended as the ecological, economical and practical alternative to traditional methods.

Jan 1, 2007

By B. Kenney

For SOFCs, composite cathodes comprising an electronically conducting electro¬catalyst (e.g. LSM) and an conically conducting electrolyte material (e.g. YSZ) are considered to improve the electrochemical performance by extending the active reaction zone to regions beyond the electrolyte-electrode interface, as in the case of conventional cathodes. Interpretation of experimental data for composite cathodes, however, is complicated by the mixed conducting behaviour which results in local overpotential distributions throughout the composite cathode. These local overpotentials depend on many factors, such as the composition, particle size, porosity and thickness of the cathode. Reliable experimental data obtained from composite cathodes requires carefully crafted microstructural parameters in order to minimize the overpotential variations. A mathematical model of a composite cathode was developed using coupled differential equations describing transport and consumption of chemical species, oxygen ion and electrons. Simulations under various oxygen concentrations were used to obtain the reaction order of the oxygen reduction reaction. An apparent po2 dependency was then extracted from the predicted Rp vs P02 data. It was found that this p02 dependency can be significantly influenced by the micro-structural parameters of a composite cathode, primarily due to local overpotential distributions.

Jan 1, 2005

By Michael P. Davies

Mine waste facilities, and in particular tailings impoundments, are one of the highest risk aspects of any mining venture. There are far too many recent examples of how real and/or perceived physical or environmental impact from one of these facilities has had enormous economic impact on both the specific project and the overall parent mining company. In many cases, such dramatic impacts have followed a period where a due diligence of the mine had been carried out (e.g. in an acquisition, merger or similar) or an internal or otherwise audit had taken place. Consequently, it is suggested that there is a need for an audit/due diligence framework to assist those processes in terms of assessing mine waste facilities. This paper presents a recommended framework for completing either an audit or due diligence assessment of mine waste facilities under a number of typical scenarios. The framework will be of relevance to reviews carried out prior to mine construction, during operations and for mines that have been in a care and maintenance position and are to be re-opened. Concepts of risk management are introduced as an essential part of the recommended framework. The paper should be of value to current and prospective mine owners involved in stewarding an area of significant risk to viability of their mining venture. The paper should also interest prospective lenders to these ventures.

May 1, 2007

By T. Grammatikopoulos, SGS Canada Inc.

"The Nechalacho rare metal deposit, located in the Northwest Territories, Canada, is currently being taken through Feasibility Study by Avalon Rare Metals Inc. QEMSCAN analysis and supplementary electron microprobe analysis were utilized to identify and quantify the mineralogy of the deposit, and determine REE distribution among the minerals. QEMSCAN mineralogy was performed to provide textural information on the mineralization, determine the variability of the ore and identify REE domains, and the liberation and association of the REE minerals. The sample matrix consists predominantly of silicate minerals. The REE minerals include allanite, monazite, synchysite, columbite, fergusonite, and bastnaesite. Zircon is present in considerable amounts and is a REE carrier. Fergusonite and zircon account for most of the HREE, and monazite, allanite, synchysite and bastnaesite the LREE. QEMSCAN mineralogical data is extremely valuable in assessing the mineralogy of the ore. The data are implemented to define the mineralogy of the ore body, support metallurgical test work, and predict recoveries and grades.INTRODUCTIONThe term rare earth elements (REE) is used to describe the 15 lanthanide elements or metals and, more recently, the metals yttrium and scandium, which display similar physical and chemical properties.Economic and potentially economic REE deposits form two main groups, a more commonly occurring “light rare earth element” (LREE) group containing lanthanum, cerium, praseodymium, neodymium, and samarium and a less commonly occurring “heavy rare earth element” (HREE) group which, in addition to the LREE, contains elevated concentrations of the more valuable REE, europium, gadolinium, terbium, dysprosium, holmium, yttrium, erbium, thulium, ytterbium, lutetium and scandium. The first group is hosted primarily by carbonatites and the second by highly alkaline (Na + K > Al) silicate igneous rocks. The LREE are produced mainly from bastnaesite, monazite, etc., while HREE are produced almost exclusively from low-grade secondary ion adsorption clay deposits in which the REE are adsorbed onto the surfaces of kaolinite and halloysite, clay minerals produced by the weathering of granite and sediments. HREE are also found in fegusonite, zircon, xenotime, etc but are not produced presently from these minerals. China is responsible for 97% of the World’s production of the REE, mainly from the giant Bayan Obo, carbonatite-related deposit and from the clay deposits mentioned above.Quantitative automated mineralogy is increasingly being applied to ore deposits. It helps users to understand and improve mineralogical parameters for geological and metallurgical purposes. Data include textural characterization, to quantification and distribution of ore and gangue minerals, liberation and association of the REE minerals. The data can be used to define mineralogical domains and predict the metallurgical response of the ore (Gunning, de Souza, & Grammatikopoulos, 2009)."

Jan 1, 2012

By W. Griffith

"While oxalic acid precipitation practices are commonly applied on purified rare earth elements (REEs) pregnant leaching solutions (PLS), few efforts have been reported using oxalic acid (OXA) to recover REEs directly from untreated PLS. High oxalic acid demand is the most significant issue in all these direct oxalic precipitation (DOP) practices. Preliminary research on DOP of REE from a dilute PLS originating from an acid bake followed by water leaching was conducted. At 75°C, the oxalic acid demand was between 12 and 18 times the stoichiometric requirement for complete REE precipitation. Conducting DOP at 25°C had superior REE recovery but the product purity and filterability declined. Between 75°C and 100°C, REE recovery increased with increasing temperature. When sodium hydroxide was used to adjust the pH during DOP, in the range of 0.5 to 1.5, higher pH benefited REE recovery. Using ammonium hydroxide in place of sodium hydroxide, the REE recovery was reduced by close to 5%. Sodium chloride addition to the PLS was also investigated and the results showed that at both 75°C and 25°C, the REE recovery was enhanced substantially. At 25°C, when the oxalic acid addition was controlled at 4.7 times the stoichiometric requirement, the overall REE recovery reached 95% with the addition of 240 g/L NaCl. Other reagents such as KCl, NH4Cl also showed significant enhanced REE recovery at the same oxalic acid addition. The addition of sodium sulphate appeared to largely enhance the precipitation of LREE but inhibited the formation of HREE oxalate. All results indicate the formation of rare earth double salts may play an important role in REE DOP sulphate media.INTRODUCTIONThe conventional routes for recovering rare earth elements (REEs) from a sulphuric acid pregnant leaching solution (PLS) involves an initial purification step for removal of iron, aluminium for example by precipitation through neutralization, followed by precipitation of REEs as hydroxide, oxalate or carbonate salts, or by bulk solvent extraction for REE recovery (Xia, 2013). Another route was used by Bayan Obo in their historical flowsheet, where the PLS was first subjected to double sulphate precipitation, then the remaining REEs, mostly heavy rare earth elements (HREE), were recovered by oxalate precipitation (Li, 2011)."

Jan 1, 2016

By A. E. Flynn

Introduction The purpose of this paper is to record the results of researches on anhydrite that have been undertaken at the Nova Scotia Technical College during the last two or three years. The work was carried out in the Mining Department of the College, and several investigators were engaged on the work from time to time. Messrs. R. E. Hanson and K. M. Ed devoted their mining theses to the investigation, and Messrs. J. C. Hall and G. W. Baker were engaged on the work during the summers of 1928 and 1929, respectively. The writer was responsible for the initiation and direction of these researches, which were made possible by the financial assistance of the Department of Mines of the Province of Nova Scotia. Nova Scotia is the leading Province in Canada for gypsum production, its output being about a million tons per year, or over 80 percent of the production for the whole of Canada. The commanding position of Nova Scotia in this regard is due to the abundant supply of gypsum and its proximity to areas of intense utilization in the eastern United States. The resources of gypsum are contained in a total area of 627 square miles of gypsiferous rocks, so that an enormous reserve of this mineral is available. Present operations are confined to the highest grade and most easily worked deposits close to water transportation.

Jan 1, 1930

By H. J. McQueen

The irregular history of Mg wrought products is briefly described. The temperature and strain rate dependence of microstructural evolution, flow stress and ductility of Mg alloys in hot working, are described. The flow curves rose rapidly to a peak stress which was lower as temperature T rose and strain rate e declined and above 300°C the curves extended into plateaus until failure. Clearly grains not oriented for slip undergo mechanical twinning in the initial stages (a 0.15) at all temperatures. Basal slip proceeds in suitable grains and in the twins. The stress concentrations at grain and twin boundaries lead to slip on non-basal systems and to the formation of subgrains with greater dynamic recovery (DRV) at higher T or lower e. With increasing strain, misorientation builds up resulting in dynamic recrystallization (DRX) first at twin intersections and later at grain boundaries which have become quite serrated. Even after extensive straining at high temperatures, the new grains are found mainly along the boundaries of the original grains, leaving their centers with only basal slip except when nucleation at twins leads to completion of DRX throughout a grain. Despite similar shear modulus and melting point to Al, hot mechanical forming behavior of Mg alloys differ due to differences in crystal slip systems, twinning, and second phases. Moreover, the influences on forming of alloy additions (solutes, segregation in casting, dispersoids, precipitation) and impurities are not as well catalogued as for Al. Despite the benefits from dynamic recrystallization, varied grain orientation effects, heterogeneous substructures and the resulting stress concentrations result in considerably lower ductility for Mg alloys at the same stress level as for Al materials. Application of these theories to extrusion, rolling and forging and the effects on product properties are surveyed.

Jan 1, 2006

By C. Díaz, A. D. Dalvi, C. E. O'Neill

"Roast-reduction smelting (RRS) of nickel concentrate, combined with flash smelting of copper concentrate, was one of the process options that Inco considered as a means of meeting its 1994 sulphur dioxide abatement target at its Copper Cliff operations. RRS involves deep roasting the nickel concentrate in fluid bed roasters. The roaster off-gas is treated in a sulphuric acid plant, and the low sulphur calcine is reduction smelted with coke in an electric furnace to yield a sulphur-deficient matte. The latter material is converted to Bessemer matte in Peirce-Smith converters, with minimal evolution of sulphur dioxide, and the converter slag is reverted to the electric furnace. Excellent nickel and cobalt recoveries (Ire obtained. This paper discusses the development of RRS, including extensive commercial scale testing at Inco's Thompson Smelter, and its key operating parameters. IntroductionReduction of sulphur dioxide emissions has been a long-standing endeavour at Inco. At the company's Ontario Division, as shown in Figure 1, sulphur dioxide emissions were reduced from about 2 million to 685 000 tonnes per year over the period 1970-1985. Most of this impressive improvement was the result of a sustained research effort which led to increased rejection of pyrrhotite from the ore during milling while maintaining an acceptable nickel recovery. Between 1970 and 1985, the combined grade of the separate nickel and copper concentrates feeding the Copper Cliff Smelter increased from about 10070 to about 'lIJ0J0 Cu +Ni and the combined S/(CU +Ni) ratio decreased from about 2.8 to 1.65."

Jan 1, 1994

By B. C. Legg, G. L. Tiley

"Many of the ore bodies presently being developed are in remote locations and are, or will be, served by electrical power supply systems of limited capacity.The largest single components of the electrical systems of an underground mine are usually the production hoist drives; the power demands of these drives vary continuously throughout each hoisting cycle.Before 1970mine hoists were driven by either wound rotor induction motors or DC motors in conjunction with motor generator sets.Static Power conversion equipment now costs less to purchase and install and is claimed to be more efficient than motor generator sets. On the debit side, however, it can adversely affect the hoist motors, it operates at relatively low power factors, and it produces harmonic currents.This pa per discusses the effects of static equipment on both DC motors and AC power systems, and evaluates the relative consumption of the three classes of drives."

Jan 1, 1993

By Ray Mason

Marathon PGM Corporation?s PGM-Cu Project in Northwestern Ontario (Figure 1.0) serves as a case study to describe the process involved in advancing a deposit from grass roots exploration to the completion of several feasibility studies and the parallel commencement of environmental permitting. Through the following examination of historical exploration activities, it is clear that these activities are directly related to economic stimulus, mostly measured by downturns in the mineral industry. Other factors that influence the success of exploration advancing to feasibility and new mine development includes the ownership of the mineral claims, which also changes under these economic influences and the crucial role of interactions between the Company, the Crown and First Nations. The Marathon PGM-Cu deposit is hosted within the Eastern Gabbro Series of the Proterozoic Coldwell Complex, which intrudes and bisects the much older Archean Schreiber-Hemlo Greenstone Belt. The sub-circular complex has a diameter of 25 km and a surface area of 580 km2 and is the largest alkaline intrusive complex in North America (Walker et al., 1993). Mineralization at the Marathon PGM-Cu deposit is part of a very large magmatic system that consists of at least three cross-cutting intrusive olivine gabbro units that comprise the Eastern Gabbro Series of the Coldwell Complex (Figure 3.2.4-3). In order of intrusion, the three gabbroic units consist of (1) Layered Gabbro Series, (2) Layered Magnetite Olivine Cumulate (LMOC) and (3) Two Duck Lake (TDL) Gabbro. The relative size and abundance of the gabbroic units decrease in the order Layered Gabbro Series>TDL Gabbro>>LMOC. Late quartz syenite and augite syenite dikes cut all of the gabbros but form a minor component of the intrusive assemblage.

May 1, 2010

By N. Kubo

Sumitomo Toyo Copper Smelter and Refinery was commenced in 1971, and its production capacity of sulfuric acid was 550tpd at the beginning. In 2001 Toyo Copper Smelter and Refinery projected to expand its copper production capacity to 450,000tpy, and now the project is still in progress. To achieve this expansion project, 4,000tpd of sulfuric acid production capacity is necessary to the acid plant. So as a part of this project, the construction of the new converting and absorbing line and the improvement of the existing converting and absorbing line were carried out from 2001 until 2005. Then the production capacity of these 2 lines has already reached the target, 4,000tpd of sulfuric acid. Moreover, at the design of the new line, we adopted several latest technologies and materials in order to construct the world's leading acid plant. Basing on the operation performance of the new line, we have improved the existing line in 2005. Both of these 2 converting and absorbing lines are working quite well and contribute to big energy saving and excellently stable operation. Cu2007

Jan 1, 2007

By J. Pepin

When using alternating current submerged arc welding (SAW) to produce pipes from microalloyed linepipe steels, it is critical to balance penetration depth and deposition rates, in order to minimize the number of weld passes while still maintaining good heat affected zone (HAZ) microstructures and properties. A series of bead-on-plate (BOP) submerged arc welds were performed on X70 steel, using different waveform variable settings (i.e., balance, offset and frequency). Weld bead cross-section profile deposition and penetration areas were measured, and both Vickers hardness and Charpy V-notch impact testing were performed. Both single electrode and tandem electrode welds were evaluated.

Jan 1, 2011

By Charlie Harper

Open Pit Mining of Golden Band Resources? EP Gold Deposit Golden Band Resources Inc. (GBN:TSX-V) is Saskatchewan's newest Gold Producer. Located in the La Ronge Gold Belt of northern Saskatchewan, GBN has over 875 km2 of claims with 12 known gold deposits and 4 former producing mines. Production has begun at the Roy Lloyd Mine (Bingo Deposit), to be followed initially by our EP and Komis properties. Development of the underground infrastructure at the Roy Lloyd Mineis continuing and on schedule. Production from these deposits will feed our centrally located and 100% owned Jolu mill. We have our provincial environmental permits in place, and we have an established infrastructure including a 400 tonne-per-day mill, year-round road access, and access to grid power. Construction of the grid power line and the above ground tailings facility are now complete.

Nov 1, 2011

By Hassan El-Shall, Ayman El-Midany, Patrick Zhang

Bench and pilot scale testing results suggest that significant improvement in dewatering characteristics of fine particles could be obtained by the addition of fibrous materials. Case studies involving flocculation and dewatering of wastes from phosphate, bauxite, and kaolin processing plants are presented in this paper. Several dewatering techniques were investigated, including sedimentation thickening, filtration, centrifugation, dewatering on screens, and seepage-induced dewatering and consolidation. Advantages and limitations of commercial application of some of the developed techniques arc discussed.

Jan 1, 2004

By Geoffrey Gilbert

Rossland is in the West Kootenay district; 5 miles north of the International boundary and 4 miles west of Columbia River at Trail. The first claim in the district was located in 1887; but there was little activity until 1890; when the showings that later became important were staked and development began. Production increased rapidly from 1; 800 tons in 1894 to a peak of 360; 000 tons in 1903; and averaged 286; 000 tons for the next 13 years. It declined sharply in 1917; and continued to decline until the closing of the main mines in 1928. Between 1933 and 1941 leasers mined a further 137; 000 tons. Total output has been about 6; 200; 000 tons; with average recovery of 0.47 oz. gold; 0.6 oz. silver; and 1 per cent copper. The total value was $82; 500; 000; of which aboµt three-quarters was in gold; the camp still leads the province in total gold produced. Ninety-eight per cent of the tonnage came from a small compact area worked by four inter-connected mines : the Le Roi (39 per cent); Centre Star (25 per cent); War Eagle (24 per cent); and Josie (10 per cent); all now owned by the Consolidated Mining and Smdting Company of Canada; Limited.

Jan 1, 1954

By K. Eklund, T. Ahokainen

The Flash Smelting process is the most used production method for primary copper in the world. The basic idea of the Flash Smelting is to utilize the thermal value of sulfidic concentrates and melt the reaction product, in controlled conditions, without a need for external energy. This basic principle is utilized both in matte smelting and in Direct-to-Blister Flash Smelting Processes. In this paper, the behavior of normal (CuFeS2) concentrate of FSF-process is compared to the behavior of high grade feed material produced by Outokumpu Concentrate Upgrade Process with the aid of computational fluid dynamics (CPD) simulation using add-in subroutines developed by Outokumpu Technology. Results consist of the information concerning the behavior of the suspension, reaction efficiency and other parameters concerning the reactions of the feed material. It will be shown that, using the Upgrade Process, the throughput of copper from the Flash Furnace can be almost tripled.

Jan 1, 2007

By E. Poiate, P. R. Cabral, A. V. N. Santos, P. V. M. Costa, C. S. Amaral, A. M. Costa

This paper discusses the design of underground salt caverns, opened by solution mining, for the production of brine and storage of natural gas under high pressures. The caverns are located in the salt basin in Maceio City, Alagoas State, at the northeast region of Brazil. Special attention is given to the geomechanical structural design of the caverns using computer codes specially developed for the simulation of excavations in salt rock formations, considering validated constitutive creep laws under different initial stress states and temperatures. The behavior of sedimentary rocks intercalations presented in the salt layer is simulated using elastic-plastic models. The excavation of the caverns by solution mining is also simulated starting from a geostatic initial equilibrium state of stresses, with a unique formulation only implemented in these computer codes, without the need of the application of boundary stresses to the model in order to develop the initial state of stresses. These computer codes have being used in the design of several clusters of caverns for brine production used as raw material of Poly Vinyl Chloride (PVC) of the Chemical Industryin Brazil. These computer codes and methodology were also applied to the design of the underground conventional potash mine in the state of Sergipe, overlying tachyhydrite and carnallite with very high creep strain rate. They have also been used in the design of the pre-salt oil wells through thick layers of stratified salt rock in Santos Basin, for the exploration and production of the pre-salt reservoirs in Brazil. The constitutive creep equations implemented in the codes are based on a double mechanism creep law. The creep constants adopted in the simulation are taken from a previous investigation carried out on an experimental panel of the potash mine, considering the stratified geology with different salt rocks of the basin where the mine is located. These constants were also obtained by lab tests under different confined and differential stresses and temperatures.

Jan 1, 2015

By Donald A. Cranstone

"This paper provides a bird's eye view of the pattern of gold discoveries since 1823, the year of Canada's first gold find, up to 1983. Within this 160-year period, more gold was discovered in Canada during the last ten-year period (1973-1982) than during any previous decade. The record suggests that the potential for further major gold discoveries is high, which bodes welt f or the future of Canadian gold mining.IntroductionCanada has an impressive history as a gold producer. Since 1921 we have occupied second or third place among the world 's gold producing nations, after South Africa and most of the time the U.S.S.R. Canadian gold production over the last hundred years has added up to some 6 per cent of all-time world production.The sharp rise in the price of gold in the 1970s led to a surge of gold exploration, which in turn resulted in the discovery of significant quantities of gold in Canada. How do these recent discoveries rate in comparison with those of the more distant past? For example, are the quantities of gold in notable discoveries of recent year s, such as Hemlo and Detour, in the same league with the amounts of gold discovered around 1910 in the Porcupine and Kirkland Lake district s of Ontario? Can the combined gold content of the recent discoveries be likened to that o f the almost 40 major Canadian gold deposits, along with numerous smaller ones, discovered in Canada during the 1920s and 1930s? What are the implications of the more recent gold discovery record for future rate s of gold discovery in Canada?This paper attempts to glean answers to such questions from an overview of the period that begins in 1823, the year of Canada's first gold discovery. Gold deposits come in two major types: placer deposits and lode deposits in solid rock . Placer gold is distributed in sand and gravel. Gold in solid rock occur s mostly in gold ore filling fissures."

Jan 1, 1985

By David Penswick

Despite anecdotal evidence to the contrary, the mining industry is not in decline. Rather, the world?s largest mining companies are among the most consistently profitable companies in any industry. In many cases, profitable mining companies have been built around a few large scale, long life mines. These criteria for success ? size and long life ? have led to the current preference for deposits that can be exploited using open pit methods. However, developments in the science of block caving have resulted in this mining method achieving costs and productivities that are competitive with the largest open pits, while achieving widespread applicability. One implication of the low costs and widespread applicability of block caving is that some current open pits are possibly too deep.

May 1, 2003