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By Linruo Zhao, Qi Yang, Akihiro Sato

TiN coating has a wide range of tribological applications from wear reduction of cutting tools to erosion protection of gas turbine engine compressor components. The performance of TiN coating depends on its microstructure, mechanical properties and adhesion strength which are influenced by the coating deposition process. In this study the effects of cathodic arc deposition conditions on the microstructure, hardness, adhesion and erosion resistance of TiN coating were investigated experimentally. It was found that varying deposition temperature, substrate bias and N2 pressure could derive a processing window in which TiN coating with superior erosion performance can be fabricated.

Jan 1, 2010

By J. S. Scott

"The Quemont property comprises 640 acres lying directly north of and adjoining the Noranda (Horne) mine. During 1926 to 1928, United Verde Extension Mining Corporation sank a shaft 235 feet and did 3,000 feet of development work on the 215-foot level. Between 1929 and 1930, Quemonr Mining Corporation deepened the shaft to 926 feet, and did further lateral work and drilling on the 500- and 900-foot levels. This work was confined to an area close to the south boundary and met with little encouragement.Following a period of idleness a magnetic survey was made in the winter of 1944, followed in the summer of the same year by some 6,000 feet of drilling. The first successful hole was drilled in February, 1945, from the ice of Osisko lake.To the time of writing, 131,000 feet of drilling, surface and underground,have indicated a large tonnage of gold-silver-copper-zinc ore, and although some knowledge of the geology and structure is emerging, it is too early to draw definite conclusions. The following brief description deals only with those structural features that are reasonably well indicated."

Jan 1, 1954

By K. Fujita, T. Kikuchi, Y. Sakamoto

Ceramic fibers were classified as a category 2 carcinogen by The European U legislation. Therefore we developed non-fibrous insulating castable which utilizes n porous aggregate, which is composed of Calciumhexaluminate. Although at beginning we applied alumina cement as binder for non-fibrous insulating castable, kind of formulation had a poor resistance to spalling. We developed non-fibrous insulating castable without alumina cement. This solved a problem which pre\ formulation had a poor resistance of spalling. We applied a new non-fibrous insub castable for reheat furnace in steelworks, then we could achieve good result which condition equivalent to ceramic fiber insulating castable.

Jan 1, 2004

By S. F. Dudka, T. Dang, M. L. Wong

Abstract - The Nui Phao W-F-Cu-Au-Bi deposit is located in one of the poorest regions of northern Vietnam. The deposit is currently undergoing a pre-feasibility study by Tiberon Minerals Ltd., with a view to developing what would be the largest WO3 mine and one of the five largest fluorite mines in the world. The project is being planned in close compliance with World Bank and national guidelines for environmental and social protection. Development of the mine is anticipated to bring the following benefits: remediation of serious pre-existing environmental conditions (natural and anthropogenic heavy metal contamination and acid rock drainage); provision of employment and training, and thereby wealth, to local communities; significant tax and royalty payments to government, which will be reinvested as social spending; and development of municipal and industrial infrastructure to build sustainable post-mining communities. The role of governments at all levels is critical in guiding and facilitating this process. This paper was written prior to development of the mine, and relays the intentions of the developers. Future studies will be needed to evaluate the degree of attainment of sustainable development objectives, both during mine operation and after closure.

Jan 1, 2003

By Andrew D. Lapworth

The use of geological and grade models has been standard practice in mine design for many years now, with a wide range of software available to create and analyze the models. Although geotechnical parameters are also of vital importance for mine planning, there has been very little in the way of commercially available systems for integrating geotechnical data into the mine planning and design process. Sirovision is a new technology based on digital photography for automated, safe and accurate 3D mapping of geological and geotechnical features in rock faces. Datamine has integrated this capability into its product range so that Sirovision becomes an integral part of day-to-day face mapping, mine geology and geological / geotechnical modeling in both open pit and underground mines. This results in improved fragmentation for loading, hauling and processing, and for open pits local geotechnical conditions can be taken into account to improve slope design and control. This paper describes some of the ways that geotechnical modeling can be used to create more refined and cost effective mine designs and then discusses the role of Sirovision in enabling the raw data required for such modeling to be collected quickly, safely and reliably.

May 1, 2007

By C. A. Rowland

"Plant owners and operators, plant designers and grinding mill manufacturers are giving much attention to the design and manufacture of autogenous and semi-autogenous grinding mills, particularly the mills that have large diameters and draw power up to 10,000 hp and greater. Reliable designs giving long operating lives are required in today 's ore processing plants.This paper reviews bench-scale and pilot-plant testing to determine first if the ore is suitable .to be ground by these methods and then reviews the data obtained from pilot-plant testing that is used to select the mills and the grinding circuit. The paper then discusses the use of the pilot-plant results to design the mills. The most important pilot-plant data used for mill design are power and the amount of ball charge to be used. The mill size selected is a combination of these factors. Pilot-plant data not only establish power requirements, but can be used in the selection of the type of drive, variable speed or fixed speed, and the operating procedure to be followed. This leads into the mill control circuit to be used. The total charge in the mill, the type of drive and mill discharge arrangements are needed in the calculation of stresses and bearing loads. Conclusions reached from pilot-plant work are used to obtain data for process design, and autogenous and semiautogenous mill design should be part of any test program incorporating either or both of these grinding methods."

Jan 1, 1981

By A. L. Holloway, N. M. Soonawala, L. S. Collett

"Since the late 1970s, a major R&D program has been under way in Canada to assess the concept of disposing of nuclear fuel wastes in deep plutonic rock. Atomic Energy of Canada Ltd . (AECL), a federally-owned corporation, has been given the responsibility of directing this research (Rummery et al., 1983).The Underground Research Laboratory (URL), constructed in a granite pluton 15 km east of Lac du Bonnet, Manitoba (Fig. 1) is a major component of the Canadian Nuclear Fuel Waste Management Program. A diverse geotechnical experimental program is being carried out during both the construction and operating phases of the URL. This program involves detailed geological mapping, rock mechanics and hydrogeology studies, and geophysical surveying, to characterize the rock mass surrounding the shaft, and it has been described by Simmons et al. (1983). As part of the construction-phase program, ground-penetrating radar (GPR) surveys are being carried out during excavation, in an attempt to delineate fractures both ahead of the excavation and behind the walls of the excavation. This paper presents the results of surveys performed during shaft excavation and describes a procedure for plotting the data.Ulricksen (1982) cites examples of radar surveys to evaluate surficial deposits, such as peat, sands and gravels, and cavity detection in subsurface hard rock. Fowler (1981) used radar for fracture and clay vein detection in coal seams.In Canada, pioneering work in GPR has been done by Annan and Davis since the mid-seventies (Annan and Davies, 1976). Their work concentrated on problems relating to permafrost in the Arctic ."

Jan 1, 1986

By S. Wood

"Plastic Filled Valley (PFV) wire rope represents a significant development over the design of conventional wire rope. A sealing thermoplastic is impregnated under controlled conditions of temperature and pressure into a conventional lubricated wire rope to produce a lattice of plastic which surrounds and separates the strands from each other and from the core. Metal-to-metal contact is thereby alleviated and the lubricant is sealed in. The wear resistance, rope breaking load, fatigue resistance and crushing resistance are all increased. The result is a rope which offers exceptional service life.Laboratory tests carried out in Canada and at the University of Stuttgart, in West Germany, confirm the increase in fatigue life. The field trials conducted so far have indicated that the results obtained in the laboratory can be duplicated in the field.IntroductionIn times of double -digit inflation, the consideration given to operating costs throughout industry commands considerable attention. The same can be said of the mining industry. A set of large-diameter wire ropes used on the huge draglines in strip mining can cost in excess of $100,000. Because a machine may use three sets of rope s each year, it is clear that the costs of wire rope can contribute a considerable percentage to any operating budget. As wire rope is a product which is used extensively throughout the mining industry, it would appear timely to turn our attention to any ""Method of Extending Wire Rope Service Life"" in order that wire rope life can be optimized and wire rope costs can be minimized."

Jan 1, 1982

By G. Begin

"The expansion undertaken at Selbaie in 1985 necessitated an adaptation and expansion of the equipment maintenance system. This paper relates briefly the stages of transformation of the maintenance administrative structures, work methods and tools. The maintenance in a mechanized mine requires an expenditure level in the order of 20% of the total operating cost of the enterprise. Thus, the maintenance organization was modified to apply more computerized planning and follow-up, and the role of preventative maintenance was further advanced.IntroductionAs far as maintenance is concerned at Selbaie, the scenario described herein is a resume of the current situation. Although positive results have been obtained, this outline is in no way a detailed account of a fail-proof maintenance system.Once zone A-I was put into production, the expansion the mine experienced in 1985 had a direct impact on the equipment maintenance system. As centralized as it was in the beginning, the system is now partially decentralized.The over-all changes to the maintenance department demonstrate the flexibility required by organizations in new situations. In spite of the exceptional results obtained before the expansion, it became evident that both the maintenance and production sectors would have to be combined. In doing so, a more appropriate coordination of maintenance work could be obtained and the maintenance staff would obtain a more detailed knowledge of the equipment in each sector. In addition, by keeping the general and specialized departments centralized, it was possible to offset the negative effect s of a decentralized system, namely too much manpower."

Jan 1, 1990

By M. Vaccarini

In this paper a possible methodology to supplement a predictive control approach is reported. The benefits deriving from the application of a predictive control on complex buildings lay on its capability of adapting in advance to the conditioning needs of indoor environments. In fact, the mere reactive control is usually affected by response delays, mainly determined by latency intrinsic in systems and by the massive nature of buildings, which slows down their response to changeable inputs. Hence, systems are too often solicited at their maximum power to recover against comfort deficiencies, and high consumptions are had. This paper reports on the application of a predictive approach to the Passeig de Gracia (PdG) metro station in Barcelona, which is a considerably high energy demanding building and where ventilation systems are used to control both comfort and air quality. Although an extensive simulation for estimating energy savings obtainable through that approach is currently ongoing, in this paper we detail the several components which make up a ?predictive control framework? and we perform a preliminary demonstrative simulation. In particular, the whole setup is formed by: a detailed model of PdG, which simulates the station?s ?real state?; a control model, which optimizes a given cost-function; probabilistic predictive models to infer the future state of the systems, given the assumptions on the control actions by the control module. The outcomes of this paper show that the procedure is applicable and preliminary results over a short simulation horizon of half a day are reported.

Aug 1, 2013

By Mario E. Rossi

Geostatistical conditional simulations are becoming increasingly popular as tools that provide models of uncertainty at different stages of a mining project. They have been used as grade control tools in daily operations, to assess the uncertainty of minable reserves at the project?s feasibility stage, and to assess mineralization potential in certain settings. Other applications include assessment of recoverable reserves, resource and reserve classification, and drill hole spacing optimization studies. All large-scale applications of conditional simulations intend to benefit from the ?correct? (or ?accurate?) characterization of uncertainty, adequately describing the variability observed from the data and its impact on the final objective. The objective of this paper is to compare the ad-hoc ?uncertainty model? provided by a traditional classification scheme with the probability intervals resulting from a conditional simulation model. It is argued that the uncertainty model derived from the use of classification schemes is of little practical use to the mining company or operation. The paper emphasizes differences in uncertainty based on the size of the mining unit considered and the extraction method, and local geological differences. Most importantly, it discusses confidence intervals for these mining units, as compared to the relative precision envisioned by a typical classification scheme. The application described in this paper is taken from a medium-sized Cu open and underground mine in northern Chile, and it demonstrates the impact of several variables on the resulting conditional simulation models. It also compares a more ?traditional? resource classification scheme applied, and the wide difference in local confidence intervals for each mining unit.

May 1, 2001

By J. P. Mogan, E. D. Dainty, K. Katsuyama

"The Volvo BM 861 U articulated truck is one of the few underground diesel units manufactured by an organization which shares the same corporate roof as the engine manufacturer. As a consequence, the unit has provided an opportunity for the characteristics of the entire system- turbocharged aftercooled engine, transmission and exhaust scrubber- to interact to minimize emission levels. The performance of the components of the system, as evaluated by full-scale dynamometer testing, is summarized. The over-all effect of the various innovations was a 38% reduction in the recommended ventilation level over that of the bare engine.IntroductionThe Mining Research Laboratories of Energy, Mines and Resources Canada is required, as part o f the certification service of the Canadian Explosive Atmosphere s Laboratory, to test the exhaust emissions of diesel engines, and to recommend appropriate amounts of fresh ventilating air to minimize the risks to health of underground personnel working with, or in the vicinity of, such diesel engines. Volvo BM AB of Sweden made application for the certification of the BM 861 U truck during a period in which EMR personnel were engaged in a number of research projects concerned with improving the environment in dieselized mines. One such avenue of research was the venturi or high-energy scrubber; as the BM 861 U was equipped with this type of scrubber , EMR and Volvo BM agreed to cooperate in a considerably more extensive investigation than would be normal for a certification application. The outcome of some of this research is summarized in this paper."

Jan 1, 1981

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 A. J. Smethurst, S. B. Hearn, S. Boskovic

"The problem of crud in solvent extraction is well known and can be a major handicap and operational issue. Colloidal silica can cause a number of problems including interfering with flocculation, initiating crud formation in solvent extraction (SX), decreasing SX extraction kinetics and increasing SX phase disengagement times. Flocculation can be utilized to remove some of the troublesome particulates but colloidal silica does not flocculate well and presents a different problem requiring innovative chemistry to solve. Coagulants can assist by facilitating the removal of this colloidal silica by promoting the agglomeration of the particles to a size which can be more readily settled or flocculated in solid/liquid separations. This is achieved when the coagulants bind to the surfaces, displacing water and destabilizing the colloids, whereupon they bind to each other which facilitate their amenability to conventional flocculation.INTRODUCTIONSilicate minerals are abundant in the upper layers of the Earth’s crust, and there are few mineral deposits without significant levels of gangue silicates. Silicate minerals include the pure silicas, such as quartz and other silicate containing minerals such as clays, chlorites, feldspars, as well a vast number of less common silicates.During the acid leaching of ores, two types of fine silica particles are released in solution from the dissolution of the host mineral. The first consists of partly depleted silicates, and the second is colloidal silica, which forms in solution. It is this second type which has the potential to cause crud formation as well as poor solution clarities, slow filter rates and excessive flocculant usage (Figure1)."

Jan 1, 2016

By P. D. Duever, P. J. Readyhough, P. L. Silveston

"The Plastojrost apparatus, developed by Ritter and Juranek in the 1960s has been modified primarily, to automatic temperature control. A limited investigation of carboniferous and cretaceous coal samples showed that both coals undergo the same changes when coked in the Plastofrost unit. Dilatometer plastic range and total dilatation correlated well with the Piastofrost plastic range for the carboniferous Appalachian coal, but not for the cretaceous western Canadian coal. Work to elucidate the characteristics of some western Canadian coals using the Plastofrost is in progress. IntroductionCoke quality is critically affected by the properties of the plastic phase in the coal-to-coke transformation. Since these properties exist in a coke oven and are not measurable, they are approximated by standard laboratory tests, such as free swelling index, plastometry, and dilatometry. Of particular interest to us is the anomalous behaviour of western Canadian coals of cretaceous origin. By many predictive methods, these coals should not produce coherent cokes. When coked in pilot scale test ovens, in fact, they produce cokes of good stability. They typically make up 20% of Japanese coking coal blends and are also used in South Korea, Mexico, Brazil, and several European countries. This anomalous behaviour has been studied in our laboratory<8.9.1O). Plastic properties or rheological tests examine just the external ramifications of the coal-to-coke transformation. To understand the process, however, microscopic examination of the coal and coke seems to be needed. The Plastofrost unit has been shown to be a convenient means to this end."

Jan 1, 1987

By Bruce C. Smart

"Very little attention was given to the regulation of uranium mills by the Atomic Energy Control Board prior to 1974. The ore grade treated by Canadian mills in the past was in the order of 0.08 - 0.3% U and it was not difficult to keep the exposure of workers well below regulatory limits. Furthermore, uranium milling has also been substantially free of occupational illness because environmental control has been generally satisfactory (l).The discovery of higher grade ore bodies in Canada has resulted in higher radiation levels in one mill and this has partly contributed to a need for increased radiation monitoring in the mill. In addition, as greater insight is gained on the effects of radiation, the implementation of the ALARA principle is being stressed at all mills.The concept of ALARA was emphasized by the ICRP (International Committee for Radiological Protection) in 1977 and stands for '""as low as reasonably achievable'"". It is based on the premise that no proven threshold for potential effects of radiation exists and that the actual individual exposure should therefore be kept as far below the regulatory limit as possible, economic and social factors being taken into account."

Jan 1, 1982

By R. J. Grant, D. W. Scott, M. A. Cooper, E. R. Shannon

"The Brunswick No.12 site concentrator processes 10,500 tonnes per day of a complex lead, zinc, copper and silver ore producing four concentrates by differential flotation. Research over the years has led to increased understanding about the mineralogical and flotation characteristics of the ore. A pilot plant study conducted at Lakefield Research, primarily designed to investigate the technical feasibility of semi-autogenous grinding, provided an opportunity to test recent theories about grind size,, reagent schedule and flowsheet configuration.A fundamental approach was taken with each of the unit processes involved in grinding and flotation. Basic operating and metallurgical criteria were established in each area and a step-by-step implementation program initiated in the plant.Significant improvements in metallurgical and financial performance have been realized through the application of basic grinding and flotation principles using conventional milling equipment and without major capital expenditure. Current operating practice is detailed and metallurgical advancements cited.INTRODUCTIONBrunswick Mining and Smelting operates one of the world's largest lead and zinc mines near Bathurst, New Brunswick. Brunswick is a publicly traded company with majority ownership held by Noranda Minerals (63%). In addition to the No. 12 underground mine, the company operates a lead smelter and phosphate fertilizer plant in Belledune, N.B. and maintains a 25% interest in a joint venture with Noranda Minerals' Heath Steele mine near Newcastle, N.B. Through the four operations, a total of 2000 people are directly employed with fixed assets totalling Cdn$187 million (BM&S, 1991)."

Jan 1, 1993

By V. Chatain

The environmental assessment of historical mining sites contaminated with various inorganic species, as also the determination of remediation targets require a better knowledge of pollutant-bearing phases. The objective of this paper was to investigate the operational fractionation of arsenic (As) in an As contaminated (ca. 3 wt%) soil collected from a gold mining site in France, where mining activities and smelting processes of gold ores took place until 2004. Single and sequential chemical extraction procedures were performed to evaluate the potential mobility of As according to the fractions to which it was associated in the contaminated soil, and also the part of As sorbed onto soil particles. These procedures used provided information on the nature of As fixation processes in the mining soil studied. Results showed that As appeared mainly sorbed (ca. 72%) with iron on the soil particles, in particular amorphous iron oxyhydroxides. These results confirmed a potential risk of arsenic mobilization under acidic and/or reducing conditions, which frequently occur in mining environment. This research evidenced the importance of the knowledge of As-bearing phases to better predict the mobility of this pollutant and in turn improve the management of As contaminated sites.

Aug 1, 2013

By M. Gauthier, A. C. Brown

"Monometallic zinc mineralization associated with marbles of the Grenville Supergroup in the Mont-Laurier Basin of Quebec is found to be stratiform and to occur (1) within limited zones of dolomitic marble and (2) more precisely along contacts between these marbles and adjacent metaclastic units. Massive sphalerite with accompanying pyrrhotite and pyrite is the prime exploration target, and commonly gives rise to good geochemical anomalies, but generally weak and ambiguous geophysical responses. Disseminated sphalerite in dolomitic marbles may signal proximity to interesting massive mineralization, although, due to weathering, this broadly disseminated mineralization may not be detected easily on outcrops. It is concluded that the western and possibly the eastern margin of the Mont-Laurier Basin constitute favourable areas for continued exploration.IntroductionThe Grenville Supergroup marbles of Ontario, Quebec and New York State host numerous occurrences of zinc mineralization (Fig. I) , several of which have been periodically mined since the beginning of this century (Fig. 2). The Balmat Edwards district of New York is the giant of this depo sit-type, with the production since 1915 of some 20 million tons of ore grading 10% zinc, and acknowledged current reserves of approximately equal tonnage and grade. At present, there is renewed interest in the potential for similar mineralization throughout the Grenville Supergroup, and this paper outlines some of the geological, geochemical and geophysical guidelines that may be employed in the search for new ore. The geologic guidelines are derived especially from lithologic and stratigraphic features which survived intense, multiphase deformation and metamorphism.Although major portions of the extensive Grenville Supergroup hold potential for zinc mineralization, the present study is confined to a known zone of mineralization in the Mont-Laurier Basin of Quebec. Concurrently, we are compiling information on the regional metallogeny of the basin so that our conclusions can be applied to areas of similar Grenville Supergroup host-rocks elsewhere."

Jan 1, 1980

By A. Burduk

The traditional approach to managing information flow between a mine underground and overground, applied in copper mines of KGHM Polska Miedz S.A., is mostly based on exchanging spoken information using the mine telephone network and printed documentation. This way of information flow significantly influences effective use of time of a shift foreman employed at a mining division. In order to minimise multiplication of significant information generated as paper documentation, a concept of an IT system module to input basic data concerning operation of the mining division was developed. The idea is based on computer software that permits inputting data in the underground and their immediate sending to the overground. The above-mentioned solution will permit significant reduction of administrative work time that each foreman has to do on each shift. The time saved on filling forms and communication will permit the foreman and the other workers involved in information flow to spend more time for execution of their basic duties. In the case of the supervision employees working in the overground, the IT system will allow all the interested persons to be informed directly, with no necessity to transfer the information on the situation in the given mining division by turns from one to another. On the other hand, saving time on administrative works will permit the foreman employed in the underground executing more detailed inspection of workplaces in his subordinate mine division. Thus, availability of the foreman for the mining division operation will be improved. KEYWORDS

Aug 1, 2013