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By R. W. Guill

"The Apex Mine is currently scheduled to be brought back into production by Hecla in the first quarter of1990. Its projected productivity rate will be exceptionally high for a small underhand cut and fill mine.The ore mined at the Apex Mine occurs within a pipe-like structure as a series of iron oxides containing both gallium and germanium, plus significant amounts of silver, zinc, lead, and copper.Ground conditions in and around the ore zone have dictated that unique approaches be utilized. To date, these have included a prototype 0.5 cu. yd diesel LHD, and the use of fibrous shotcrete in 4ft by 7ft headings, and the first pneumatically-placed cemented backfill in North America. Above all else, it is the combination of new technologies with a small and dedicated workforce which has allowed for the successful development of this ore body.IntroductionThe Apex Mine is an example of the typical small underground project. It has high grade, but low tonnage and is deposited in poor ground. In such cases, conventional planning and thinking generally results in an uneconomical evaluation and negative production decision. Fortunately, some unconventional thinking was allowed to take place during the planning and evolution of the Apex Mine development. The result now serves as an example of how such unconventional thinking can lead to the type of innovations described below.The job necessitated the development and use of new equipment and materials to execute a highly flexible underhand cut and fill mine design/pneumatic backfill concept, that must be constantly modified as different than assumed conditions become evident in and around the ore zone."

Jan 1, 1990

By Clyde Williams

If you would allow me some liberties, I would re-state the title of this talk as Scientific Research, Our Greatest Resource, because that title would represent more clearly a present-day conception of the metals and minerals situation. It is a subject worthy of careful consideration. Canada and the United States are so similar and interdependent in their national economies that, in the following discussion, examples of conditions in the United States may? be interpreted to apply to Canada as well. Moreover, it is a striking fact that the per capita value of mineral production in Canada and the United States in 1940 was almost the same. Therefore, in the consideration of this subject, I have made no attempt to differentiate between the two countries. The consumption of the world's mineral resources in the last few decades, and particularly during World War II, has been so enormous as to require some form of magic to ensure the continued progress of civilization in the face of a diminishing supply of these resources which are so critically essential. As Dr. C. K. Leith pointed out in 1941, industrial expansion has been so great that, during the first forty years of this century, the world used more of its mineral recourses than in all preceding history. And this did not include the all-out consumption during the succeeding five years of war.

Jan 1, 1947

By M. Dosoudil

"Continuous pressure filtration is a modern process for the mechanical dewatering of flotation concentrates of coal and similar coal slurries. This method will give a lower moisture content than classical vacuum filtration, the improvement lying in the range 5% to 15%. Eighteen coal slurries have been examined in this survey. They are representative of a wide spectrum of filtered slurries. IntroductionDuring the last five years, a number of coal slurries have been tested either in the laboratory or with a pilot plant. The test pressure ranged from one to six bar. The results have been evaluated by mean s of a computer. Determination of the filter capacity and the resulting moisture content and energy consumption has been made with respect to the continuous pressure filter, Amafilter construction-type KDF (Fig. I) . Standard sizes of these filters are 60 m2, 90 m2 and 120 m2.The continuous pressure filter is a horizontal filter with a level tank. Six filter axles are mounted on a rotating main shaft, each with a particular number of elements attached. The elements rotate on their axes and move along a circular trajectory. Periodically the elements submerge into and emerge out of the slurry. A constant air pressure is maintained above the suspension, thus providing the pressure gradient necessary for filtration. The filtrate together with the dewatering air flows through the elements into the hollow axle and out of the filter."

Jan 1, 1987

By J. R. Morris, A. E. Ball, G. W. Kuzyk

"AECL Research has constructed an underground laboratory for the research and development required for the Canadian Nuclear Fuel Waste Management Program. The experimental program in the laboratory will contribute to the assessment of the feasibility and safety of nuclear fuel waste disposal deep in stable plutonic rock.In 1988, AECL extended the shaft of the Underground Research Laboratory (URL) from the existing 255 m depth to a depth of 443 m in cooperation with the United States Department of Energy (USDOE). The project, which involved carrying out research activities while excavation and construction work was in progress, required careful planning. To accommodate the research programs, full-face blasting with a burn cut was used to advance the shaft. Existing facilities at the URL had to be modified to accommodate an expanded underground facility at a new depth. This paper discusses the design criteria, shaft-sinking methods and approaches used to accommodate the research work during this shaft extension project.IntroductionThe Underground Research Laboratory (URL), a major geotechnical research facility, has been developed by AECL Research, 120 km northeast of Winnipeg, Manitoba. The URL is part of the Canadian Nuclear Fuel Waste Management Program (CNFWMP), which is assessing the concept of nuclear fuel waste disposal in a vault deep in stable plutonic rock of the Canadian Shield (Hancox, 1986). The URL provides a representative environment to conduct a wide variety of geotechnical research relevant to nuclear waste disposal. Extensive characterization and monitoring programs were carried out prior to construction and will continue during operation. The operating phase experiments began in 1989 and will continue until the year 2CXXl (Simmons, 1990). Figure I shows the present extent of the URL facilities and the proposed future development."

Jan 1, 1991

By Craig H. B. Leitch

"In describing the alteration of porphyry systems, the term ""secondary K-feldspar"" appears to be an oversimplification. A better term would be ""alkali feldspar"" alteration, because in actual fact the replacement feldspars show gradational changes from an albite, which is important in some systems, to an alkali feldspar containing minor orthoclase molecule, to true orthoclase.There are several textural varieties of secondary alkali feldspar present in the porphyry systems studied from British Columbia, Australia and New Zealand. These include, in apparent increasing order of alteration intensity: clear albite (An10); patchwork albite (Ab5-10); chessboard albite (An0-10) "" irregular albite "" (An0Ab100 to Ab90r10); untwinned "" anoralbite"" (Ab90Or-Ab70Or30); and orthoclase (Ab440Or60-Or100)·The exploration significance of these varieties of alkali feldspar is that their gradation in composition, from sodic to potassic, may be linked to a corresponding increase in intensity of alteration. Thus, there is a tendency for more sodic alteration feldspars to characterize weak, sub-economic deposits, or the fringe zones of stronger deposits; the more potassic alteration feldspars may provide an exploration vector toward more highly mineralized zones."

Jan 1, 1981

By C. Hu

A MOS capacitor hydrogen sensor array is reported for hydrogen gas distribution mapping. Si(100) was used as substrate for film deposition. After silicon oxide growing on the silicon surface with dry thermal oxidation, palladium film was sputtered on silicon oxide as hydrogen-sensitive gate material in MOS structure. The 3x3 sensor array was patterned on silicon substrate and packaged in one chip. Sensors' response was test with impedance analyzer. The sensors in array were calibrated in the hydrogen concentration range from 10ppm to 10000ppm. The 2D hydrogen concentration distribution was obtained with the calibrated sensor array.

Jan 1, 2005

By D. Marotte, M. David

"A new exploration procedure is proposed for volcanogenic massive sulphide deposits of the Abitibi belt. ""Samples"" of acidic volcanic rocks (Si02 > 60%) were compiled from the literature. From the 574 samples collected, 322 were used in each of a number of experiments. Forward inclusion linear discriminant analysis performed on the untransformed geochemical data shows a general depletion in Na20 and CaO along with an enrichment in MgO for a ""proximal"" group of samples relative to a ""distal"" one. The percentage of misclassified samples reaches 20% to 30%, but test sets shows good stability.The exploration procedure was applied to the Normetal deposit, where the authors took 160 samples during the summer of 1977. It quickly leads to the definition of targets for more detailed exploration together with a good recognition of the old known deposit.IntroductionVolcanogenic massive sulphide deposits in the Abitibi belt (Quebec) are mainly found in rhyolites or acidic pyroclastics in the uppermost portion of a calc-alkaline volcanic series (Descarreaux, 1972). The deposits are thought to have formed syngenetically by the action of volcanic hydrothermal exhalations during the waning episode of a felsic volcanic cycle (De Rosen Spence, 1976). Alteration pipes of disseminated sulphides are commonly present. Metal deposition from hot springs, initiating convection cells in a submarine environment, may have been the dominant process in ore formation (De Rosen Spence, 1976)."

Jan 1, 1981

By Michael K. O’Leary, William D. Coplin

"Risks from political instability and government policies restricting equity ownership, local operations and transfers of payments affect the profitability of foreign mining ventures. More than seat-of-the-pants judgments and old-boy networks are required to anticipate these risks and to take actions appropriate to offsetting them. A system for making political forecasts, called the Prince System, and a series of charts relaying risk s to a production of key minerals will be presented.IntroductionFirm s with extractive operations outside their home country do not have to be told that political stability and government decisions play a big role in the success o f their operations. The takeover of copper firm s in Chile during the Allende administration in 1971 and the recent decision by Venezuela to reduce Reynolds Metals equity share in a smelting operation from 50% to 28% are two examples of hundreds of events that have determined the profitability of extractive operations over the past decade. Both risks and opportunities for international firms seeking to produce and market raw materials are heavily affected by political conditions. While news of political events travel much faster than in the past and host governments are more clever in shaping the risks as well as the opportunities, politics has always been part of the mining business.What has changed is the need to be more systematic in approaching the assessment of political conditions and how it affects business. The increasing costs of extractive operations, the need for long-range planning, the importance of financial arrangements and the world-wide scope of man y firm s' activities require that the assessment be updated continuously and be comparable across different countries and different types of investments. Political risk analysis, the assessment o f macro-political changes and specific governmental decision s on the operations of extractive industries needs to become as systematic and integrated into corporate decision -making as economic analysis has become over the past two decade s."

Jan 1, 1983

By Victor Rudenno

"Previous methods have employed statistical analysis to model future mineral resources. The method presented in this paper uses Zipj's Law to determine the size and grade of tin deposits still to be discovered. The law is applied independently to both known deposit tonnage and grades. A probability distribution for both 'tonnage and grade is computed/or those deposits still to be located and then, by applying a correlation between tonnage and grade, a distribution of the probability of metal content discovery is obtained.By considering an economic cut-off in metal contained in a deposit, the probability of economic success for the next tin discovery is computed, both for a world discovery and for the special case of Tasmania, Australia. The results indicate a probability of 11-37% on a world-wide basis and 18% chance of economic success in Tasmania.IntroductionIn the past , most attempts to determine the probability of success in finding an economic mineral deposit have relied on the accumulation of statistical data. These data are then used to predict a suitable frequency distribution to assess the probability of finding a deposit of a given size and grade (Singer,1975).The method not only relies on one having sufficient data, but also on the assumption that the data are not biased and that the distribution (usually log-normal) is a correct one. The method presented in this paper, to analyze tin deposits, uses Zipf's Law, which has been recently applied to oil, uranium, lead-zinc and gold deposits by Folinsbee (1977) and to Western Australian gold deposits by Rowlands and Sampey (1977). Tapp and Koniuszko (1978) have applied Zipf's Law to mineral distribution patterns in the Northern Australian orogenic provinces, which has enabled them to make predictions with a relatively small data source."

Jan 1, 1981

By Jiachen Wang

Longwall top-coal caving mining is one of the major mining methods for extracting thick coal seams in China. The top-coal caving longwall mining was began to use in the 1980s in China, and got the rapid development. The development of the top-coal caving mining technology in China, the achievements and the theoretical aspects progress of this method are described in detail in this paper. And the main technical model of China's top-coal caving mining is introduced in this paper. This paper also introduces the application of large-cutting-height mining in China and the technical level it has reached.

Aug 1, 2013

By G. E. Norman, R. E. Michelutti

"One of the major objectives of Falconbridge has been and continues to be, to minimize the impact of its operations on the environment around its Sudbury operations.The approach to achieving this objective and the results, are discussed under the following topics .I . Sulphur Dioxide Emission Improvements.2. Effluent Treatment Improvements .3. Effect of the Envrionmental Improvements.Sulphur Dioxide Emission ImprovementsHistoryThe rejection of pyrrhotite in the concentrators is one method of reducing the amount of sulphur to the smelter and therefore the sulphur dioxide emissions. In the 1950s and 1960s, Falconbridge developed the capability to remove 54% of this pyrrhotite. Numerous attempts were made to increase this amount by treating the pyrrhotite for recovery of nickel and in some cases elemental sulphur. Processes tested and operated were: hydrometallurgical pilot plant, roast-leach commercial operation and nickel-iron refinery. None of these processes proved to be commerically successful for both technical and economic reasons. Falconbridge therefore redirected its efforts to reducing sulphur emissions by improving its smelting process under The Smelter Environmental Improvement Project. A major component of this project was the installation of a sulphuric acid plant to recover the S02 in the roaster off-gases."

Jan 1, 1984

By C. -M. Katsari, G. N. Anastassakis

"Copper is considered one of the most important industrial metals because of its properties (conductivity, malleability) and variety of uses. Approximately 70% of the global copper is used for various electrical applications, with a significant part of copper originating from recycling, since copper can be recycled and re-used countless times, without any loss of performance and difference in the quality of recycled copper in comparison to that from ore. Copper recycling significantly contributes to natural resources conservation, waste minimization, energy saving, and overall cost reduction. Approximately, 35% of the globally produced copper originates from recycled copper.The objective of the current work is to investigate the recovery of copper from electric wire scraps using wet shaking table as an alternative to air separation methods that prevail over the wet ones in recycling processes. The tests were carried out using feed of correspondingly high- and low-grade in copper. In the first case, the wire scraps had been subjected to shredding only, prior to tabling separation; in the later, the low-content tailing of prior air separation was used as feed ?n table separation.In regard to testing, the following factors were examined: table tilt, water flow-rate, and reciprocating speed. The results of the tests clearly denote that copper wire separation from plastic polymer is feasible, as in most cases, table separation resulted in heavy products of high purity in copper and high recovery, and tailings of very low copper grade. The results of the current work clearly denote that wet tabling can be applied efficiently for the separation of recycled copper wire from plastic, as an alternative to air separation methods, as well as for the recovery of copper from the low-grade tailings derived from air separation methods."

Jan 1, 2016

By John E. Udd

The stability of a rock mass is influenced by the presence of discontinuities. In assessing stability, it is required that one should know the frictional and cohesive properties of these contained weaknesses. In the study performed by the authors, a number of samples of diamond drill core containing open discontinuities were tested in shear. The results obtained were compared with values which resulted from back analyses of instabilities in the field.

Jan 1, 1979

By Trevor McGiddy

"Australia's prosperity relies significantly on income generated from exports of resources and agricultural products. In 1989-1990, coal was Australia's most valuable export commodity, contributing. A $5.7 billion or 14% of all export income.The abundance and quality of its coal resources and the proximity of Australia to the rapidly developing economies of Southeast Asia were significant factors that encouraged export-oriented growth and investment and will continue to do so. On the other hand, the 1980shighlighted the sensitivity of the industry to international changes in supply and demand, currency and socio-political forces.Following many years of disappointing returns for investors, mainly as a result of falling Australian dollar coal prices, resolve will be necessary to maintain competitiveness with resource-rich nations. In recent years, operators, unions and governments have begun to embark on a long overdue rationalization of domestic issues in a bid to increase productivity and reduce costs.The nature of mining operations is also changing; deeper surface mines and the growth of longwall mining will require the development of new technology and skills. Other challenges emerging from the international environmental debate will require that Australia responds appropriately to demands for cleaner fuels, energy efficiency and environmental responsibility.The future development of the Australian coal industry will therefore be influenced by its own ability to become more efficient and mature in the production of quality coal products and through rational international response to environmental questions."

Jan 1, 1992

By C. F. Hews, P. N. Calder

"MIROC and The Mining Industry The Mining Industry Research Organization of Canada (MIROC), incorporated in 1975, is a non-profit organization sponsored by member companies from within the Canadian mining industry. The Canadian mining industry is a world leader in technological development and in organizational and human resources development. A prime objective within the industry is to retain this leadership and also improve its competitive position worldwide.MIROC is dedicated to support the objectives of its member companies and their common interest, and the objectives of the industry. In this context: MIROC's mission is to encourage the formulation of ideas to improve mining technology and methods by any source, and to foster the development and testing of promising initiatives in progressive steps from the early stages of conceptual and feasibility research through manufacture to delivery of new technology to the mining industry. In so doing MIROC plays an important role in the development of individuals skilled in mining research. Management ApproachMIROC's research program is driven by member companies who have interests throughout Canada. The board of directors approve projects that are acceptable to its members. While MIROC's basic research funding is provided by its member companies, about 30% of its annual research budget is now derived from royalties generated from previous research activities."

Jan 1, 1994

By T. H. Patching, M. W. Mikhail

"The gas sorption and emission characteristic of coals are important to the planning and conduct of mining operations. Methane drainage from coal strata can also provide a supply of fuel in certain circumstances. Gas emissions have also created hazards during the handling and transport of coals and the release of gas also appears to be related to the yield of fine sizes during mining and processing operations.This paper summarizes studies at the University of Alberta on the permeability and gas emission of certain bituminous coals. Permeability of 'solid' samples was found to be drastically reduced by confining pressure. An emission index, .P, which has been related to outbursting behaviour of coals, has also been related to the proportion of fine s in cleaning plants. Gas sorption isotherms are dependent on temperature, moisture content, the gas involved and the type of coal and can be approximately expressed by the Langmuir or the Freundlich equations. Sorption values in sections taken across a given seam were similar but considerable differences were found in . P indices in the different coal layers of a seam.IntroductionThe emission of gases, especially of methane, from coal has been a subject of great interest (and sometimes a matter of life and death), to those who dig and handle coal since it was first mined from underground pit s. Many studies and investigations have been carried out on gas occurrences and emissions but our knowledge of the precise mechanisms of gas sorption, desorption and flow from coal is still incomplete. It is the purpose of this paper to review the principal factors involved in these processes and to briefly rep ort some of the results that have been obtained by studies in the laboratories of the Department of Mineral Engineering, University of Alberta, and Coal Research Laboratory, Edmonton, CANMET"

Jan 1, 1986

By B. D. H. Knights, M. A. W. Bryson

Flotation of PGM ores, specifically UG-2, presents a number of technical challenges. These centre on the prevalence of chromite. Subject to over-grinding, chromite is primarily recovered to the flotation product through entrainment. This is of unique concern as it must be kept below a threshold for downstream smelting, with significant operational and monetary penalties being imposed should it exceed this concentration. A number of strategies have been developed to maximise PGM recovery in the presence of this unwanted contaminant. Specialised flowsheets form a vital basis and advanced control algorithms further enhance PGM recovery while minimising the recovery of chromite. Advances in Mineral Processing Science and Technology Proceedings of the 48th Annual Conference of Metallurgists of CIM Sudbury, Ontario, Canada Edited by

Jan 1, 2009

By R. R. Rogers

Introduction The subject of cathodic protection is not new. In 1824 Sir Humphry Davy, in publishing the results of his investigations for the British navy, pointed out that copper could be protected from sea-water corrosion by connecting it electrically with zinc or iron. Since that time much work has been clone in this field, particularly in the protection of metals from the action of sea water, neutral brines, and treated and untreated waters. Special mention should be made of the successful protection of underground pipe-lines which formerly were badly corroded by the water in the ground. So far, magnesium alloy and zinc anodes have been the most popular. However, fairly recent work has indicated that aluminium anodes will give good service under certain conditions. The principle of cathodic protection has been applied extensively in coating steel articles with zinc and in cladding aluminium alloy sheet with pure aluminium. A valuable discussion of the fundamentals and applications of cathodic protection recently was presented in the Corrosion Handbook. A useful list of references was included in the article.

Jan 1, 1949

By H. M. Roscoe

Fifty per cent. increased lump coal production and at the same time a reduction of from 20 to 40 per cent. in explosive consumption. These results were achieved by the use of the rock-dust cartridge method of stemming shots in the Ruhr coal mines, as announced by Dr. Alfred Stettbacher in the September 1923 number of the Explosive Engineer. Immediately, the explosive and the coal-mining industries on this continent became intensely interested. Considerable experimental work has been carried on in a number of American and Canadian mines during the past year, by which our engineers have become assured that the use of rock-dust cart-ridges for stemming shots increases the efficiency of explosives and promotes safety in coal mines.

Jan 1, 1924

By Francis Breton, Lei Pan, Kun Liu

"Effects of Fe, Cu and Mg minor alloying elements on creep properties of 8xxx aluminum conductor alloys were investigated by conducting compressive creep tests at 100 ºC under a constant load of 69 MPa. The microstructural evolution was studied using an optical microscope and electron backscatter diffraction technique. The creep properties were characterized by the primary creep strain in the first stage and the minimum creep rate in the second stage of creep deformation. Results showed that additions of all three minor alloying elements (Fe, Cu and Mg) demonstrated a beneficial effect on the creep resistance but individual alloying elements exhibited different impacts on creep properties. The additions of Fe and Mg showed a strong impact on both the primary creep strain and minimum creep rate, while the Cu addition displayed a favorable effect on the primary creep strain but no impact on the minimum creep rate. Microstructure observation revealed that with increasing Fe contents, the volume fraction of fine intermetallic dispersoids gradually increased while the subgrain size and misorientation angle became smaller, providing strong barriers to the dislocation and grain boundary movements. The addition of Cu moderately reduced the subgrain size and misorientation angle and in combination of solid solution strengthening it promoted the retardation of the creep deformation during the primary stage.INTRODUCTIONThe 8xxx aluminum conductor alloys offer significant advantages such as low density, high conductivity to weight ratio and low price over copper conductors and become an attractive candidate in electrical engineering and building wiring (McQueen, Chia, & Starke, 1986; Birol, 2009; Engler, Laptyeva, & Wang, 2013). The mass resistivity of aluminum conductors is one-half of copper conductors. Thus, only one-half the weight of aluminum is required for equivalent capacities. Therefore, this unique property coupled with a relatively low price of aluminum offers significant economic advantage to develop aluminum conductor alloys for electrical applications in the electrical wire industry."

Jan 1, 2016