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By Robert B. Parsons

"1984 was an eventful year in the courthouse f or observers 0/ the mining tax scene in Canada. For the first time in a number of years, the Federal Court heard several important tax cases which pertain directly to the resource industries. Tax Notes discusses/our cases that could affect the taxation 0/ operations and investment in the mining sector.Capital Gain or Income?Ever since tax reform, risk-takers in the exploration business have maintained that the taxation of capital gain s is a significant impediment to raising risk capital. It must be akin to rubbing salt in the wound, then, when an entrepreneur sells shares and the Court upholds Revenue Ca nada taxing the gain as ordinary income instead of capital gain. But, this is precisely what happened in the case of The Estate of Murray Watts, et al. v. The Queen.The issue that had to be decided by the Federal Court, Tri al Division, in this case was whether or not the profit from the sale of shares in Hearne Coppermine Exploration s Limited in 1968 was a capital gain, or income subject to tax.Hearne was incorporated in July, 1967. At that time, the three plaintiff s, together with seven other individuals, subscribed for 400,000 shares at 10 a share. The plaintiff subsequently subscribed for an additional 500,000 shares at $1.A pooling agreement was entered into by all ten shareholders regulating the disposition of any o f their shares; any sale required approval of seven of the ten initial sub scribers. It also provided for the sale of their shares 30 days after any public offering."

Jan 1, 1985

By L. C. Lien

Tower crane layout (TCL) is a typical construction site layout (CSL) problem, which is suitable for a wide range of work assignments and site conditions. Tower crane is one of the key facilities for vertical and horizontal transportation of materials, especially for heavy prefabrication units such as steel beams, ready mixed concrete, prefabricated elements and large panel formwork such as machinery and equipment, and a wide variety of other building materials within a construction site. However, it is a difficult combinatorial optimization problem to determine the locations of tower cranes with materials quantity supply and demand for engineers. Swarm intelligence (SI) was very popular and widely used in many complex optimization problems which was collective behaviour of social systems such as honey bees (bee algorithm, BA) and birds (particle swarm optimization, PSO). This study applied a hybrid swarm algorithm namely particle bee algorithm (PBA) based on a particular intelligent behaviour of honey bee and bird swarms by integrates theirs advantages. This study compares the performance of PBA with BA and PSO for a proposed hypothetical construction engineering of TCL with materials quantity supply and demand problem. Results show that PBA performs better performance than the mentioned algorithms on a proposed hypothetical TCL problem.

Aug 1, 2013

By B. Tiryaki, M. Ayhan, O. Z. Hekimoglu

Coal shearers are one of the major sources of dust and fines in underground coal mines. Despite considerable research investigations, no comprehensive in situ investigations coupled with extensive laboratory studies on the effects of drum design on generation of dust and fines have been found. It may be for this reason that many major shearer drum manufacturers persistently employ a certain drum-lacing pattern on current coal shearers, which is believed to cause excessive dust and fines in coal mines. This paper shows how respirable dust and fines are minimized under near-identical conditions when the drum lacing pattern was changed from a triple-tracking to a single tracking arrangement. A series of laboratory trials simulating in full scale the practical cutting action of tools was followed by extensive long-term underground trials during production operations in OAL (Cayirhan) Lignite mine in Turkey. The results are presented and discussed, and recommendations for proper drum-lacing in terms of respirable dust and fines are made.

Jan 1, 2002

By Philippe V. Scheers

Polycrystalline gold, glassy carbon and gold-activated glassy carbon electrodes were compared for the production of hydrogen peroxide by the cathodic reduction of dissolved oxygen. Gold was deposited on glassy carbon by sputtering with a sputter coater and by electrodeposition from a diluted KAuCl4 solution using short potential steps. The sputtered gold particles were not adherent enough, but there were no adhesion problems with the electrodeposited gold particles. The gold coverage of the glassy carbon surface could be varied by applying a different number of potential steps. The overpotential for the electroreduction of oxygen to hydrogen peroxide decreases with increasing gold coverage of the glassy carbon surface, and for gold coverages exceeding about 16 %, the overpotential is close to that observed on polycrystalline gold.

Oct 1, 2003

By P. Carlone, A. Astarita, F. Rubino

Cold gas dynamic spray is an innovative technology allowing the deposition of thin metallic layers on a bulk or sheet substrate. Titanium on aluminum deposition is very attractive to the aeronautic industry, due to the enhanced corrosion resistance and wear properties of titanium coating as well as its improved compatibility with CFRP, preserving the reduced cost of aluminum substrate. One main drawback, however, is related to the micro-porosity of the deposed layer, negatively affecting the corrosion barrier performance. In this paper, the effect of selective laser post-treatment on pure grade 2 titanium coatings on AA2020-T3 sheets was experimentally and numerically investigated. Morphological features, microstructure and chemical composition of the treated zone were assessed by means of optical microscopy, scanning electron microscopy and energy dispersive X-ray spectrometry. Microhardness measurements were also carried out to evaluate the mechanical properties of the treated coating. A numerical model of the laser treatment, based on a finite volume scheme, was implemented and solved to simulate the process and discuss the experimental outcomes. Obtained results highlighted the key role played by heat input and dimensional features on the effectiveness of the treatment.

Jan 1, 2015

By Roger Reed

It is well known that the performance and carbon emissions associated with the modern gas turbine engine depend critically upon the properties of the nickel-based superalloys, particularly those used in single crystal form. However, the design of all alloys in current use has been essentially empirical, or at best heavily reliant upon regression/neural network analysis of experimental datasets. In this paper, alloy design approaches [1] are described which are able to identify new alloy composition spaces which are worthy of experimental study. It is shown that a large amount of design data can be generated, which can be interpreted in different ways. Of course, the success of the approach depends heavily upon the accuracy of the underlying sub-models. Estimates of the creep resistance, cost, castability, density and oxidation resistance are made. It is demonstrated that these methods allow quantitative trade-offs to be made between the properties of interest.

Jan 1, 2010

In the last 30 years numerous mining plants have been developed in North America but only a handful of these have required freezing the area where the shaft was sunk. The most recent mine shaft to be sunk using this technique is located on an island off the coast of Louisiana. The project required the input and skills of numerous people in several companies, including the owner, engineers and contractors. The Cote Blanche installation is one of several mines in the area which extract salt from a dome which extends under the Gulf of Mexico. The geology of this area is, however, markedly different from others in the region because there is approximately 460 ft of water logged soil above the salt dome. Because it is not possible to sink a shaft in ground that is this soft, the overburden where the shaft is located must be frozen before excavation can take place. The Cote Blanche mine is a producing facility which was built in 1958 by the Carey Salt Company. The original facility included a 14 ft diameter production shaft and a 7 ft-8 in diameter service/ventilation/escape shaft. This system was installed by The Cementation Company. In 1996 the owner decided to improve both the mine ventilation and production hoisting system by installing a third shaft. This shaft would be designed to extract 650 tons per hour from a depth of 1600 ft and provide 500,000 cfm of ventilation to the mine at a maxium design pressure of 4 in WG. These parameters resulted in a requirement for a 16 ft finished inside diameter concrete lined shaft and a headframe designed as a pressure bulkhead. Because the mine would operate from one level only, the most efficient hoisting system for the application was determined to be a ground mounted koepe running on rope guides. With these criteria fixed Cote Blanche embarked on a program which would see construction start in June 1998 with the first salt produced in February 2001 at a cost of $US18M. The major players in the design and construction were G.L. Tiley & Associates Ltd., BLM Bharti Engineering, Freezewall Inc., Phillips Mining, Geotechnical and Grouting Inc., Don Hart Consulting and Dynatec International.

May 1, 2002

By Glenn Lyle

CEMI Introduction ? Introduction of the CAF VOD Project ? Who are our partners ? What were the Outcomes What is next

May 1, 2011

In-Country Business Development Agenda ?Siting/Permitting/Operational Planning ?Securing, maintaining, enhancing social license to operate ?Biodiversity conservation and ecosystem services ?IFC Performance Standards ?Environmental, Social, Risk Governance (ESG) ?Climate change plan

Aug 1, 2013

By Chelto. D. Smith

With the pressure on mine and metallurgical managers to take accountability for responsible corporate governance in their operational area, it is no longer acceptable to rely on central departments in the organization to manage safety, health and environmental impacts of the company?s processes. Environmental impacts exist because of the production or mining process. Some of the inputs to the process are natural resources and some of the outputs of the process are the inputs to the environmental control equipment, plant and the environment itself. Environmental management therefore needs to be incorporated in production management to effectively control and reduce the impacts. Many aspects of environmental management are identical to production management and the systems to manage them will likewise be very similar. By examining key components of these two management systems a decision can be made whether environmental management and production management are structurally similar and can be integrated into a combined IT solution.

May 1, 2009

By J. M. Hong, H. K. Zheng, R. Hu, C. B. Zhou

The Jinping-I double curvature arch dam, located in the middle reach of the Yalong River and with a maximum height of 305 m, is the world highest dam of the same type that has been completed. Since the second and third periods of the reservoir impounding, after which the reservoir water level was raised by about 200 m, a significant amount of leakage was observed out of the drainage holes deployed in the lowest drainage tunnel at the left-bank abutment at EL. 1595 m, with a pressure of 0.3 MPa at one typical hole when it was blocked. In this study, a number of analyses including water quality analysis, digital borehole imaging, tunnel geological mapping and in-situ groundwater monitoring were performed to investigate the source of leaking, the leakage passages and the performance of the grouting curtains. An inverse modeling procedure combining the orthogonal design, finite element forward modeling of the transient seepage flow, artificial neural network and genetic algorithm was invoked to further evaluate the permeability of the foundation rocks whose permeability was underestimated in design, using the in-situ measurements of flow rate and piezometric head. The geological structures that lead to the leakage were identified and the seepage flow behaviors in the dam foundation and the left bank abutment were assessed. Given the connectivity nature of the sub-vertically oriented fractures that induce the leakage event, it is found that some of the drainage holes with relative larger amount of discharge could be closed or blocked for reducing the amount of leakage without remarkably increasing the pore water pressure in the foundation rocks.

Jan 1, 2015

By J. C. Loretto

"OPENING REMARKS Yesterday and today we have heard some very interesting papers on operating matters and some of you are probably wondering what we are now doing talking about Communications in Plant Design. Let me tell you! Before the techniques we have heard being discussed can be used, there has to be a properly operating plant. It is certainly a fact that many mineral processing plants achieve only limited success and a number of them can even be said to be failures. Some of you sitting here are probably living with operating problems that are clue to errors in the design.If the histories of these problem plants are examined, it will be found that in many cases, the necessary skills were available during the period of the plant design. There was extensive operating know¬ledge together with a full range of project expertise. Why then the failures? In a substantial number of cases it can be traced to the old, old problem of communications. As plants get bigger, money costs more and smooth startups become more important, it becomes less and less economic to fix up any design errors during plant operations.During our careers in mineral processing, nearly all of us will be involved in at least one plant design and I feel that it is as well if we understand some of these communication difficulties that can lead to a problem plant. There is little point in us being experts in mineral processing if the knowledge we have acquired doesn't somehow get incorporated into the plant.I would, therefore, like to present this short paper that mentions a few of the significant communication problems that can occur during the design of mining and mineral processing plants, together with some thoughts on answers to these problems."

Jan 1, 1973

By Claude Hubert, Alex C. Brown, Pascal Marquis, D. M. Rigg

"Numerous studies of the Bousquet mining district, Abitibi, Quebec, mainly following the successive discoveries of new gold deposits over the past two decades, have led to a broad range of genetic hypotheses for their gold deposition. A compilation of petrographic, structural, and geochemical data indicates that the gold deposits are composed chiefly of pyritic schists derived from felsic and mafic volcanic and volcaniclastic protoliths, and of auriferous massive pyrite hosted by pyritic schists of felsic affinity. The deposits are typically located within zones of local pyrite enrichment and advanced-argillic alteration which are in turn enclosed within much larger zones of disseminated pyrite included in regional-scale, commonly anastomosing, zones of sericitic alteration.Overprinting relationships between three sets of folds and foliations indicate that the host-rocks of the gold deposits have retained the imprint of three successive generations of ductile deformation resulting from regional dynamothermal metamorphism. Sericitic and advanced-argillic alteration, together with massive sulphide deposition, are interpreted to have taken place prior to the onset of the ductile deformation, based on observations 1) of altered fragments of wallrocks which are enclosed within massive sulphide bodies and were thus preserved through regional metamorphism, 2) of the syntectonic deformed pyrite, and3) of the syn-tectonic porphyroblasts of andalusite, garnet and plagioclase. The orebodies are oblate to prolate, and the pyrite-gold mineralization is typically vein-type, distributed in foliation-oblique and foliation-parallel veins. The gold-bearing structures postdate all foliations, and are associated with retrograde alteration assemblages that are pseudomorphic after pea~-metamorphic porphyroblasts in host-rocks, and with cataclasticfabrics that overprint syn-metamorphic pressure-solution features and annealing fabrics in pyrite.Retrograde gold-bearing assemblages indicate a chemical disequilibrium between the ore-forming fluids and their host rocks. This disequilibrium rules out the possibility that gold was remobilized from its own host, and suggests, instead, that the ore-forming fluids and their metal contents had an allochtonous source. Stable and radiogenic isotope analyses indicate that the fluids had a metamorphic origin, and that the associated alteration took place after the culmination of the Kenoran orogeny."

Jan 1, 1990

By K. Barr, F. Grenier, J. Hettinger

"To reach the Hemlo Gold Inc. objective of becoming the lowest cost, safest Canadian gold producer while causing no environmental damage, management embarked from its inception on a strategy to build an organization which would foster employee involvement wherever possible. This paper describes the organizational structure and how various innovative concepts have been implemented.BACKGROUNDThe Golden Giant Mine in the Hemlo area of North Western Ontario is owned by Hemlo Gold Mines Inc. 50.1% is controlled by Noranda. The mine commenced operations in March 1985 at a modest production rate. After it reaches full production by the end of 1988, with completion of underground development work, the mine is expected to operate at 3000 t/d and produce in excess of 300,000 ounces of gold per annum. This makes it one of the three largest producing gold mines in North America.Two other companies, Lac Minerals and Teck-Corona, operate mines on either side of the Golden Giant Mine. Noranda Geco Division is located 55 kilometers to the north at Manitouwadge. The majority of Hemlo Gold's 270 employees live in Manitouwadge where a mix of accommodation was constructed and made available for purchase by employees. Bus transportation is provided to and from the workplace with modern coaches. The housing and transportation policies were implemented prior to start-up and designed to help attract and maintain good employees.As shown in Figure 1, the operation is divided into five operating and support departments with each reflecting a high degree of departmental control and responsibility. For example, the mill department is responsible for all aspects directly relating to the milling complex including safety, operation, mechanical maintenance, assaying, instrumentation, and environmental control. Similarly, the mine department is responsible for all phases of operation, mine engineering, geology, and maintenance of underground mobile equipment. The plant department is responsible for maintenance of hoisting plants and conveyances, underground stationary equipment, all site electrical services, surface buildings, housing and yard maintenance. Efforts are made at every level of the organization, from departmental organization to individual job assignments, to ensure responsibilities are clear and that they encompass complete functions."

Jan 1, 1988

By George R. White

"The Phalen Colliery, the Cape Breton Development Corporation's flagship, is now producing thermal and metallurgical grade coal in Eastern Canada's Sydney Coal Field. The colliery is a drift mine operating under the waters of the Atlantic Ocean. Improved mechanization, including a 2200 tonne per hour cable conveyor, and the introduction of modern retreat longwall mining methods as part of the Phalen concept are now paying off in better productivity and low operating costs. Geological conditions within the coal field are consistent with plans for ever greater outputs in the 1990s. Although much of the current production improvement is related to uprated machine capacity and simplified mines planning there is potential for even further development in the areas of maintenance, process control and engineering. Human resource development will also be a key factor. These programs are now well under way and Phalen Colliery is poised for top results in the 1990s. Comparison of the CBDC's top producer with similar operations elsewhere in the world, quantifies that potential.IntroductionAn exciting new mining project which has recently started production on Canada's East Coast has been conceived and designed to be one of the most modern and productive coal mining operations in North America.As with all mining operations, the business is basically that of material transportation. Daily, the product is transported many kilometres from the underground face to the surface and then to washing facilities. Men, materials and equipment are transported to and from the surface and the operating faces and services, such as electrical power, ventilating air, fresh water, discharge water, communications and compressed air are supplied throughout the operation to cover operating requirements. On all accounts the operation has been designed to take advantage of the latest proven technology."

Jan 1, 1990

By J. A. Vonhof, R. O. van Everdingen

Since 1949, a total of 59 disposal wells have been installed in Canada to inject liquid wastes from refineries, mining operations and chemical plants into subsurface formations at an ever-increasing rate. Well depths range from around 600 feet to almost 5,500 feet; injection rates range from 0.5 (U.S.) gpm to more than 1,000 gpm for individual wells; wellhead injection pressures range from a slight vacuum to over 500 psi. Apart from strictly technical considerations of well design, the geological, hydrodynamic and hydrochemical conditions at the disposal site have a strong bearing on the safety and success of such operations. Prevailing hydrogeological conditions in large portions of the country do not allow safe subsurface disposal.

Jan 1, 1973

By J. Groppo, W. Zhang, R. Honaker

"The flotation of monazite is depressed when using hydroxamic acid as a collector in the presence of calcium ions which may exist due to the dissolution of minerals such as calcite. Minor dosages of sodium hexametaphosphate (SHMP) were found to effectively depress calcite, whereas the flotation of monazite was not impaired in single mineral flotation tests. However, in a mixed mineral flotation system, monazite flotation was depressed significantly. The mechanism of hydroxamate adsorption on monazite and calcite, the depression mechanism of calcite on monazite, as well as the depression mechanism of SHMP on calcite and monazite were studied using micro-flotation, electro-kinetic, and adsorption tests. Findings indicate that the adsorption of hydroxamate on monazite was due to chemisorption while adsorption on calcite was a result of physical interaction. SHMP significantly increased the negative charges of calcite surfaces which depressed the adsorption of the hydroxamate anions on the calcite surfaces due to an elevated electrostatic repulsion force. When calcium-rich minerals such as calcite are mixed with monazite, the calcium ions dissolved from the mineral surfaces specifically adsorb onto the phosphate oxygen sites on the monazite mineral surfaces thereby causing depressing effects. The addition of SHMP to suppress collector adsorption on the calcite surfaces interacts with the calcium species that were specifically adsorbed onto the monazite surface, which prevents hydroxamic acid adsorption onto the rare earth oxygen sites due steric hindrance and results in the flotation depression of monazite. INTRODUCTIONAs one of the commercial rare earth ores, monazite has been widely exploited to produce additives for catalysts, batteries, alloys, etc. Because of the complexity and the fine nature of some monazite ores, methods such as gravity, magnetic, and electrostatic separation to treat beach sand monazite fail to produce satisfactory concentrates, suggesting the use of floatation is warranted (Cheng, Holtham, & Tran, 1993). The primary associated minerals of monazite ores include ilmenite, quartz, zircon, rutile, sillimanite (Dixit & Biswas, 1969; Pavez a& Peres, 1994, 1993). Using sodium oleate as collector for monazite has been reported in many studies (Cheng et al., 1993; Dixit & Biswas, 1969; Pavez & Peres, 1994, 1993). Several investigations have reported maximum floatability of monazite occurring at pH values between 8 and 9 (Cheng et al., 1993; Dixit & Biswas, 1969). A study conducted by Pavez and Peres (1994) compared the use of hydroxamate and sodium oleate for the treatment of a monazite ore and found that hydroxamate significantly improved the grade of rougher concentrate."

Jan 1, 2016

By W. G. Miller, J. D. Scott, D. C. Sego

ABSTRACT: As part of an overall study of properties and processes influencing consolidation of oil sands fine tailings resulting from different extraction processes, self-weight consolidation tests were per-formed. Fourteen 2 m and 1 m high standpipe tests were instrumented to monitor the rate and magnitude of consolidation of seven fine tailings materials. Tests provided valuable information about the variation of consolidation related to differences in fine tailings material properties that result from a change in bitu-men extraction process (caustic versus non-caustic). In addition, the effect of adding a coagulant to caustic fine tailings was measured. Test results are presented and discussed in terms of consolidation rate long-term volume decrease, compressibility, and downward drainage. Non-caustic fine tailings had fasterinitial consolidation, which is important in tailings ponds for reducing storage capacity and returning decant water at a faster rate to the extraction plant. Similar results were obtained for caustic fine tailings with a coagulant addition. However, long-term settlement of the different fine tailings appears to con-verge to a similar value over time because it is then governed by effective stress.

Jan 1, 2011

By C. H. Bertoni

"The Superior Province of the Canadian Shield is the largest gold producing area within Archean greenstone rocks in the world, with total production of over 140 million ounces of gold. One hundred and fifty-five mines have individually produced more than 8,000 ounces, although only a relatively limited number of deposits (33) produced more than one million ounces of gold. The output from these 33 deposits accounts, however, for 85% of total gold production. The majority of grades (68%) ranges between 0.10 and 0.30 ounce per ton, and there is no linear relationship between grade and tonnage.Development of new gold mines reflects the history of gold prices. However, the response to the latest increase in gold prices was not as marked. It is concluded that gold deposits are becoming increasingly more difficult to find and new exploration techniques are urgently required.IntroductionWith most of its production coming out of the Superior Province, the Canadian Shield is the largest producer of gold from Archean greenstone rock s in the world. In total gold production, the Superior Province is surpassed only by the paleo-placers of Witwatersrand and the placers of the USSR (Anhaeusser, 1976). There has been no attempt so far to compile the historical production of the Province as a whole in a single document. The aim of this work is to fill this gap, not only for the convenience of having a complete list of gold producers, but, more importantly, as a basis on which to study the tonnage and grade characteristics of these deposits."

Jan 1, 1983

By B. W. Clyburn

"Coals from the Corporation's Lingan and No. 26 mines are classified as high-volatile A bituminous, with a very low inherent ash and containing a/l essential properties to provide metallurgical coal, with the exception of a high sulphur content. Only through proper cleaning at low specific gravity can the pyritic sulphur fraction of the coal be liberated to an extent where final sulphur meets coking standards. This first section of the paper deals with the operation of a Dutch State Mines heavy-media cyclone circuit to achieve an actual separation in the region of 1.30 specific gravity. A discussion of the parameter of control which must be applied along with an appraisal of the results obtained is included in the paper.IntroductionVery high fluidity and unusually low ash are the outstanding characteristics of coal from Devco's mines in the Harbour seam of the Sydney coal field.However, sulphur content, mainly pyritic, ranges from 1 to 2.5070. To obtain the low and consistent sulphur level required in metallurgical coking coals, preparation at low specific gravity is required .Metallurgical coke is used as the fuel in an iron blast furnace. Its sulphur content largely determines the quantity of slag required to remove it and therefore influences furnace productivity and unit costs.Typical data on the various coal properties of importance in the production of coke are included in Table I. Necessity of Low-Gravity SeparationThe design of any coal preparation plant requires the study of washability properties of the coal to be treated to determine the quantity and quality of coal produced at a given specific gravity along with the difficulty in accomplishing that separation.Their low ash content allows the important washability aspects of Harbour seam coals to be represented by sulphur! specific gravity curves (Fig. I). This particular example indicates that a yield of 54.5% is attained, at a sulphur content of 1.20%, for a perfect separating device operating with a 1.29 S.G. cut point.Material rejected from this separation still contains usable coal, which is recovered as middlings by separating at a higher gravity."

Jan 1, 1980