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By E. L. Bruce

Introduction The Outokumpu copper mine is situated in eastern Finland, 50 kilometers west of the city of Joensuu or 225 kilometers directly north of the city of Viborg (Viipuri), which is situated at the eastern end of the gulf of Finland (Figure 1). The ore-body was discovered in 1910 by Dr. Otto Trüstedt after two years of careful, scientifically-directed, search. During the early period of development of the mine, the ore was treated locally and the copper re-covered by an electrolytic process. Now the ore is concentrated by tables and by flotation. The concentrates are shipped to Germany for refining. In 1929 the mine produced 150,000 tons of ore from which between 20,000 and 25,000 tons of flotation concentrates containing 20 per cent copper were produced. Profits in 1929 were approximately half a million dollars, but the present price of copper will affect very seriously the profits for 1930. The ore reserves are given as between 7 and 8 million tons (1). The grade of ore is stated to be 4 percent to 6 percent copper, with a little zinc.

Jan 1, 1931

By J. Mcdvcka

Sustainable development has become a driving imperative for the resource industry as it is for the rest of the global business world. Being unsustainable is a risk no business can afford. Yet implementation of sustainable development practices beyond satisfaction of compulsory reporting is still sporadic. The current standard approaches to problem analysis and decision making are too narrow to capture the complexity of the issues at stake. Hence it is necessary to develop innovation in thinking and in doing. Those who search for ways to implement sustainable development use concepts such as Whole Systems Thinking and Eco-efficiency as well as tools like Life Cycle Analysis. Others develop their own instruments. In their effort to innovate they face both resistance and support within their organisation as well as within the industry or the wider context. This paper explores the factors that support, hinder and shape the sustainable development drive of the industry and proposes a comprehensive decision-making framework that links the goal of sustainability with the tools of sustainable development. This exploration is illustrated by a case study used in a doctoral research conducted on an engineering firm providing services to our industry.

Jan 1, 2007

By J. D. Aitken

"DEFINITION OF THE REGIONTHE REGION considered in this paper is bounded on the south by the 60th parallel, on the north by the Beau-fort Sea and Amundsen Gulf, on the east by Archean rocks or by highly deformed Proterozoic rocks of the Canadian Shield (certain weakly deformed Proterozoic strata being regarded as belonging to the Great Plains), and on the west mainly by the Mackenzie and Richardson Mountains.Only the unmetamorphosed strata of the region are considered; that is, the geology of the crystalline basement is ignored.SIGNIFICANCE OF THE REGIONThe region is significant from three points of view -namely, the economic, the scientific and the social. It constitutes 46 per cent of the area of the Western Canada Sedimentary Basin."

Jan 1, 1970

By Alan E. Cameron

WE assemble again today in this comfortable, hospitable Inn to begin this, the 58th, Meeting of our Society. It is just a year ago when last we met but that year was, probably, the most portentious year in the whole history of mankind. In that year, the German 'Atlantic Wall' was broached, the Rhine was crossed, and Germany, as a Nation, has ceased to be. The agony of Europe is over; convalescence may be, probably will be, slow. But blood no longer flows in Europe. Time will heal the sores, cover the scars, regenerate the industries, rebuild the cities, and re-establish the people. True, the war of all wars is not yet over. True, a bloody conflict remains . But, the power of the United Nations now converges on one target. The rain of blood will be heavy. We can hope the storm will be short. The sun is on the horizon. The light of peace 1s in the sky. What of that Peace? Are we ready for it? Have we a 'sure foundation ' for our future world? Are the footings under that foundation broad and substantial? Can we look forward with confidence to a lasting peace and a fruitful life? The United Nations, even as this is being written, are in conference in San Francisco, placing the footings, rearing the foundations for a world edifice. There are bickerings; there are jealousies. The world is tired, and a tired family always squabbles. We can, we must, believe that the decisions they make, the edifices they rear, will be better than anything we each could effect separately. It will be a compromise, probably; it will carry things that will hurt us, just as it will carry things that will hurt others. We can, we must, believe that the good of the whole is a greater good than the good of the part. Each Nation within the United Nations must sacrifice something, each part of each Nation must sacrifice something, each individual within each part of each nation must contribute something, if the whole is to be wholesome. Sacrifice and contribution must be the order of the day if the New World we are about to build is to be worth while. What of Nova Scotia? The world has travelled far in the last year; how far has Nova Scotia gone? Canada has preparations for the Peace under way; what has Nova Scotia done? Is Nova Scotia preparing counter measures for the sacrifices it must make? Is each of us ready to contribute his share?

Jan 1, 1945

By Yang Shuxin, Guo Qiliang, He Ping, Lu Lizhi, Yao Rui

"We combined stepwise regression and constrained regression statistical method to obtain the best boundary conditions for the calculation of in-situ stress field in Wushaoling tunnel using finite element method. Our numerical results reveal that: the main geologic factors contributing to the initial background stress are gravity and tectonics; the principal stress values would drop in fault zones; the angle between the maximal horizontal stress and the axis of Wushaoling tunnel is acute; Wushaoling tunnel tends to become stable when this tunnel has 2:1 ratio of the height to its width; the possibility of rock-burst exists under high stress.INTRODUCTIONStress state of engineering region is an important factor affecting the stability of project. Geological disasters in the project area are closely related to their stress environment. Wushaoling tunnel which is 20,050 meters long, lying along Lanzhou-Wuwei segment of Lan-Xin Railway in China, is the key project of Lan-Wu double-track railway. The region surrounding this tunnel is under a high stress environment. Accurate identification of the stress environment of the engineering area and the interaction between geomaterials and geotechnical engineering construction holds significant scientific and practical value for engineering design, construction, and operation.Many scholars explored and discussed the present-day tectonic stress through investigations of tectonic evolution history (Ding, & Lu, 1986), crustal deformation (Zoback, 1992), focal mechanisms (Yang et al., 2003, Xie, Cui, & Zhao, 2004), and so forth. However, the above methods would only provide the approximate direction of the principal stress in a broad region, and could not give the absolute stress values. In-situ stress measurement is one of the primary means to directly gauge the current crustal stress. However, in-situ stress measurement can only be applied in small number limited by measurement conditions."

Jan 1, 2015

By Carlos F. Perucca, Maria Virginia Ramírez A.

"Chile based SQM S.A., exploits potassium chloride rich salts at the Salar de Atacama, in northern Chile. The process includes the solar evaporation of natural brines existing in the Salar salt bed, followed by conventional flotation to recover Muriate of Potash (MOP) for fertilizer use.This paper describes a structured method developed to aid in understanding the metallurgical response of the solar evaporated salts to conventional flotation. The method uses classical metallurgical data analysis combined with laboratory and plant-scale testing, and rudimentary mineralogical studies.As a result of the study, several changes were made to the flotation circuit which produced an operation that is much more consistent and easier to control, and has an increased recovery. An optimized circuit, currently being financially evaluated, has also been conceptually designed based on the findings of this work.INTRODUCTIONSQM S.A. is the world’s largest producer and distributor of specialty fertilizers, iodine, lithium, as well as a wide array of industrial and specialty chemicals. SQM is a public corporation whose shares are traded in the Santiago and the New York Stock Exchanges.SQM S.A. exploits the mineral rights at the Salar de Atacama in northern Chile. Its production processes involve the solar evaporation of natural brines existing in the Salar salt bed, aimed at the recovery of Potassium, Lithium and Boron compounds."

Jan 1, 2004

By W. Rostoker

Packing Experiments The porosity and most of the other physical properties of a coherent mass of any material built up by the packing together of discrete particles will obviously vary with, and be governed by, the manner of association of the particles. The relation of packing to powder metallurgy has been discussed in some detail by at least two authors. Packing Theory Theories of particle packing have been put forward by C. C. Furnas and A. E. R. Westman. Although their approach to the problem is not the same, their conclusions are similar. In the process of packing, they visualize the voids of a uniformly sized material becoming filled with particles of a smaller size, and the voids between these being filled in turn with still finer particles. Obviously, if this process is carried ad infinitum, the resultant mass will have the same density as the constituent particles. In practice, of course, such a density of packing is never attained. In addition, the premise is made that successive particle sizes must fit into the voids left by the immediately larger particles- an assumption requiring definite size gradations and also particle shapes. It remained, then, for theory to correlate relative diameter ratios, and proportions and numbers of sizes of particles, for requisite packed densities. Briefly, the following principles were postulated: (a) For an infinite diameter ratio between largest and smallest sizes, an infinite number of particle sizes in proper proportion is required to give natural density. (b) For a given diameter ratio, there is a maximum number of permissible particle sizes for maximum packed density (Furnas). (c) Provided the particle shape is spherical, or approximately so, the proportions o particle sizes can be calculated. (d) The ratios of successive diameters of particles are in geometric progression.

Jan 1, 1947

By Dwayne D. Tannant

The Adra tunnel near Naramata BC experienced a fire in 2010 that burned timber sets within the tunnel and caused severe spalling of rock from the roof and tunnel walls. The nature of the damage is documented and efforts completed to rehabilitate and open a portion of this tunnel to the public are described. The use of shortcrete and rock bolts is a technically and economically superior support system to timber sets as well as being far more fire resistant.

Jun 1, 2012

By Quin Dennis

Process Optimization ?What is it really? It is NOT ?a larger fan to increase draft through a process ?a larger pump on a wet circuit ?a wider conveyor belt for solid materials ?a larger feed elevator into or out of a process These relieve individual constraints ??bottlenecks??and allow operation to the next constraint in the process ?It is also NOT about automating the operator ?which captures consistency but is not continuous optimization

Nov 1, 2011

By K. C. Armstrong, A. B. Cron, L. A. Melis

"The Johnny Mountain gold mine in northern British Columbia, owned by skyline Gold Corporation, has been in operation since August 1988. Mill operating difficulties at the start of the operation resulted in a depleted cash flow situation and quick improvements were required to generate a self-sustaining financial basis of operation. In October 1988, Melis Engineering Ltd. was contracted to identify metallurgical difficulties, implement necessary modifications, and undertake mill operations and personnel training in order to achieve production targets.This paper presents the operating difficulties which existed at start-up and describes the methodology used to overcome production problems. Metallurgical testing results are described along with the modifications made to the milling circuit to suit ore metallurgy. Plant changes led to the operation of a simple gravity/flotation circuit to recover gold as bullion and in a copper concentrate. Operation of the originally installed cyanidation circuit was discontinued. This contributed to substantial savings in operating costs and virtually eliminated environmental problems. PROPERRTY LOCATION ANR DESCRIPTIONThe Johnny Mountain mine site is located in northern British Columbia along the Iskuit River about 60 km east of Wrangell, Alaska and 275 km north of Terrace, B. C.. A location map is presented in Figure 1 and a site plan is shown in Figure 2. The complex is located on a mountain plateau about 3, 600 feet above sea level. The plateau is flanked to the north by Johnny Mountain and surrounded on the other sides by steep cliffs."

Jan 1, 1990

By J. H. C. Scrimgeour, T. Toong, R. E. Hamilton

"The principles involved in the use and application of mathematical models as an aid to the development of advanced process control computer systems are described briefly. This is followed by a brief survey of known models of this kind for the simulation of mining industry processes.The main part of the paper describes a dynamic model of the flotation process developed by Canadian General Electric. Using flotation rate constants for each species of mineral and gangue, the model provides a numerical solution of the differential equations describing cell behaviour. The cell mode] is used repeatedly as a subroutine in the •over-all-plant model. The features of the cell and plant models are described.Simulation runs from the plant model show stream .assays and other indications of plant behaviour printed typically in 1-to 10-minute steps for several hours of •Operation following typical disturbances such as changes in feed rate or reagent addition rate. The simulation can :Show expected behaviour for both uncontrolled and computer-controlled plants."

Jan 1, 1970

By Xiao min Zhou, Yan Xu, Hongzhen Liang, Xiaonan He

"With the increase of shaft excavation depth, the thickness of the shaft lining increases sharply. It is difficult to reduce thickness of lining effectively by improving high-strength concrete performance. The concept of the New Austrian Tunneling Method (NATM) is that surrounding rock plays a certain role in tunnel support. The solution should be to find the correct relationship between shaft lining thickness and rock strength, which is related with the interaction between the surrounding rock and concrete lining. The plane strain mechanics model is introduced to calculate lining thickness. Shaft lining design of Cixi Colliery in China is completed with the mechanics-based method proposed in this study. The lining design is verified through numerical simulation and field monitoring. The simulation results show that the maximum mises stress is located at the inner edge of the shaft lining. The increase of lining thickness cannot effectively reduce concrete grade. The monitoring results indicate that a lining design thickness of 900mm with C60 concrete, is safe and reliable in the shaft over 1000metres.This analytical design method can well be referenced in similar deep shaft projects.INTRODUCTION The New Austrian Tunneling Method (NATM), thought to have helped revolutionize the modern tunneling method, is the most extensive design philosophy and construction principle in today's tunnel engineering. It began to attract attention in the 1960s based on the work of Ladislaus von Rabcewicz, Leopold Müller, and Franz Pacher in Austria[1]. NATM was originally developed for tunneling in depth and in high situ-stress conditions in the Alps. The history of sequential excavation was reviewed, which highlights the progress of tunnel design and construction in Europe after NATM[2]. Structural conditions were introduced into the equilibrium of tunnels in NATM, and the additional force was estimated to stabilize the excavation of the tunnel[3].From the perspective of applied mechanics, there was no accuracy theory to explain the interaction between the tunnel structure and the surrounding ground. Numerical calculation is an effective means to study the basic mechanism of tunnel excavation[4].Based on two-dimensional modeling approaches in the past, such as NATM and other derivatives, a three-dimensional model was studied to"

Jan 1, 2019

By M. Barati, K. Ebrahimi-Nasrabadi, P. W. Scott

"The conversion of cryptocrystalline magnesite to caustic magnesia was studied experimentally at temperatures of 400–1,200°C and for calcination times of up to 8 h. A differential thermal analysis– thermal gravimetric analysis showed that decomposition begins at temperatures as low as 340°C and is completed at 600°C. Specific surface area, iodine adsorption number, crystallite size, and loss on ignition were measured to characterize the product quality. It was found that high-quality caustic calcined magnesia can be produced in a narrow temperature (600–650°C) and time range (1–4 h).RÉSUMÉ La conversion de magnésite cryptocristalline en magnésie caustique a été étudiée de manière expérimentale à des températures de 400 à 1200 °C et pour des temps de calcination atteignant 8 heures. Une analyse thermique différentielle – analyse thermique gravimétrique montre que la décomposition commence à des températures aussi basses que 340 °C et qu’elle est complète à 600 °C. La surface spécifique, l’indice d’adsorption de l’iode, la taille des cristaux et la perte au feu ont été mesurés afin de caractériser la qualité du produit. Il a été trouvé qu’une magnésie caustique calcinée de grande qualité peut être produite dans un petit écart de température (600 à 650 °C) et dans une période de temps variant entre 1 et 4 heures."

Jan 1, 2015

By W. M. Goodwin

"IntroductionIN THE preceding paper we have learned about Canada's resources of metallurgical coal. There is an adequate amount in Nova Scotia, a very large reserve on the eastern flank of the Rocky mountains, and a strictly limited supply on the Pacific coast. Added to these is an unknown quantity of coking coal in the Peace River district, at present rather isolated but possibly capable of industrial development in the future.The chief use of metallurgical coal is to make iron and steel. For this, an adequate supply of iron ore is required. So we should now scan the Canadian supply of iron ore, the possibility of its increasing use at home, and the probable markets abroad.Trade in iron ore tends to be international, as is the case with many other raw materials. The present tendency with iron and steel, in contrast, is to keep its manufacture within national boundaries, and there is no evidence that this will change much in the years to come. We should keep these two points clearly in mind when considering the disposal of iron ore from Canadian mines. We should remember, also, that the modern blast furnace and steel plant has such a large output that a correspondingly large population, reasonably compact, is needed to consume its products.Large Ore Supply in East, Small in WestCanada has now four major iron ore fields, well situated to serve adequately the eastern half of the country. Wabana .and Labrador are well placed to serve overseas markets and plants on the eastern seaboard and eastern interior of the United States and Canada."

Jan 1, 1952

By Guoqiang Lan, Jun Song, Bin Ouyang

Rare-earth pyrochlores, commonly exhibiting anomalously low lattice thermal conductivities, are considered as promising topcoat materials for thermal barrier coatings. However the structural origin underlying their low thermal conductivities remain unclear. In the present study, we investigated the phonon properties of a group of RE pyrochlores, Ln2Zr2O7 (Ln = La, Nd, Sm, Gd) employing density functional theory and quasi harmonic approximation. Through the relaxation time approximation (RTA) with Debye model, the thermal conductivities of those RE pyrochlores were predicted, showing good agreement with experimental measurements. The low thermal conductivities of RE pyrochlores were shown to largely come from the interference between the low-lying optical branches and acoustic branches. The structural origin underlying the low-lying optical branches was then clarified.

Jan 1, 2015

By Habib Zughbi, Paul Zulli

"A key step towards sustainability in iron and steelmaking is to optimise the use of raw materials and energy consumption, and consequently minimise CO2 emissions. Models based on a Process Integration (PI) approach play a key role in evaluating various scenarios and the impact of introducing changes in raw materials and operational conditions on the overall energy consumption and CO2 emissions. BlueScope uses a PI based comprehensive model for its Port Kembla Steelworks (PKSW), called the Integrated Steelworks Energy and Emissions Model (ISEEM). ISEEM is tightly coupled to the configuration of PKSW. It is based on mass and energy balances as well as thermodynamic relationships. ISEEM is a steady-state model and is used to predict overall and detailed unit-by-unit energy consumptions and CO2 emissions. It is also used for plant-based scenario modelling. This paper investigates the impact of major changes to PKSW configuration, including the shutting down of a blast furnace and cokemaking battery, on the energy consumption and CO2 emissions of the plant. It discusses some of the issues involved in updating the model and some identified opportunities."

Jan 1, 2015

By J. S. Fox

Major-element data for unaltered, unmineralized felsic host rocks from a number of stratigraphically simple, massive volcanogenic Zn-Cu(-Pb) sulphide deposits of low metamorphic grade have been compiled. The petrochemical affinities of these host rocks have been determined (by standard means and by discriminant analysis) and compared. This comparison indicates that volcanogenic deposits in felsic terrains are not restricted to the classical calc-alkaline rock association as previously thought, but can actually be hosted by rocks showing a range of iron content. There is a positive correlation between differentiation trend and are tenor. Zn-Cu ores usually have iron-rich felsic hosts (most Canadian Shield deposits); Pb-Zn -Cu ores have iron-poor felsic hosts (Japanese, Iberian and Tasmanian deposits). This parallels the antipathetic relationship between iron content and background lead levels evident in young, unmineralized, island arcs as well as in many older belts. Correlations between differentiation trend on one hand and massive ore mineralogy and the relative proportions of various rock type (including rhyolite, quartz-porphyry and coarse pyroclastic rocks) on the other are also evident. It is concluded that the recognition of a calc-alkaline differentiation trend cannot be used as a prospecting guide, as has previously been proposed. However, in view of the above correlations, the recognition of a given trend may aid in the formulation of an effective exploration philosophy.

Jan 1, 1979

By D. Yuan, L. Yan, M. J. Collins, P. Kalanchey, I. M. Masters

ABSTRACT Pressure oxidation tests have been conducted by Sherritt for a refractory gold-silver project in China. The feed contained 39 g/t Au and 970 g/t Ag; the major gold-bearing minerals were pyrite and arsenopyrite. Because the feed contained a significant amount of silver, which can be refractory to cyanide leaching after pressure oxidation due to the formation of argentojarosite, the test program included investigation of methods to enhance silver recovery. The “lime boil” process proved successful and was incorporated into the flowsheet. Gold extraction from the lime boil product solids was 95–98%; silver extraction was up to 94%.

Jan 1, 2013

By Trevor Harris, Martin Harris

"This paper evaluates the effect of grind size on the flotation performance of a platinum ore from the UG2 reef of the Bushveld Igneous Complex, in South Africa. The study was conducted on the Mintek Flotation Pilot Plant Facility, located in Johannesburg, and represented a thorough evaluation of the application of the flotation modelling methodology developed jointly by the University of Cape Town and the Julius Kruttschnitt Mineral Research Centre at the University of Queensland through the AMIRA P9 Project. A simulation model of the pilot plant data was successfully implemented, providing a set of circuit modelling parameters that appeared to be both consistent and well correlated to measurable characteristics of the ore and the pilot circuit operating conditions. The findings indicate that the methodology that was used could well provide a useful framework for developing optimisation criteria for industrial flotation circuits in combination with appropriate feed grind size and regrind size targets.INTRODUCTIONIt has long been recognised that the size distribution of an ore is one of the most important factors in the determination of the performance of a flotation process. It therefore follows that the optimisation of a flotation plant cannot be considered without due recognition of the interdependence of this process with the process of comminution. There are numerous qualitative guidelines for the selection of an optimum grind target for a particular operation. Mineralogical analysis can readily provide information on liberation as a function of grind, and the desirable particle size range for optimum mineral flotation is well established in both theory and practice (see for example Trahar, 198 1). For some operations, meeting these two criteria simultaneously is relatively simple. For the majority of operations, such mineralogically “easy” deposits, if they ever existed, have long been exhausted, and the optimum grind represents a highly complex compromise between liberation and overgrinding of both desirable minerals and gangue. This is particularly true for circuits that include regrind stages, where both primary and secondary (and sometime even tertiary) grind targets must be specified. As has been pointed out in a recent paper by Bazin and Hodouin (2001), there is little or no information in the literature to assist plant engineers in the selection of optimum grind targets for complex ore deposits, so current practice is primarily based on rules-of-thumb and experience. This problem is further compounded by the fact that once grind targets have been selected for a particular operation, the assessment and adjustment of these targets based on plant surveys is extremely difficult, time consuming and expensive, and is often not attempted unless the plant significantly underperforms relative to expectation. It is therefore clear that the development of a practical quantitative approach to this problem is a high priority for flotation research and development studies."

Jan 1, 2002

By M. B. B. Research Council of Alberta Crockford

Introduction Kootenay strata of Lower Cretaceous age contain much of the highest rank coal produced in Alberta. These strata outcrop in the foothills and mountains of southwestern Alberta and southeastern British Columbia, and the economic value of the coal seams contained in them was evident to the earliest explorers, who refer co them in their journals. Lacer, investigation of the .coal measures was undertaken by prospectors and by a succession of geologists, most of whom were in the employ of the Federal government, but some acted for private interests. Surveys by these men proved chat foothills and mountain regions hold immense quantities of high-grade coal within easy reach of transportation facilities, and their conclusions have accelerated the development of the coal-mining industry m Alberta. Among geologists who have contributed much to our knowledge of the region are J. M. Dawson, G. M. Dawson, R. C. McConnell, D. B. Dowling, J. D. Mackenzie, B. Rose, J. R. Marshall, B. Rose, J. R. Marshall, B. R. McKay, J. A. Allan, and J. L. Carr. The present paper is to a great extent a compilation of the work of the above men and of several others who have investigated the area lying between Bow river and Crowsnest pass. Space does not permit a list of all the sources of information so chat only chose of prime importance are given in the text. Data for the map and ?cross-sections of Figure 1 were taken from the following published maps of the Geological Survey of Canada: Cascade Coal Basin, Pub. 933; Canmore, Maps 322 and 323; Upper Elk River and Upper Highwood Rivers, Pub. l980; Blairmore, Pub. 1584; Southfork Coal Area Map l03A; and of the Research Council of Alberta: Highwood-Elbow Area, Map 20; and Ribbon Creek Area, Map 21. In some cases, the cross-sections have been simplified or otherwise altered, and for these revisions the writer cakes full responsibility. The stratigraphic sections of Figure 2 have been taken from published reports of the above mentioned organizations. The area covered in this paper is shown in Figure l. It is wholly within Alberta, and reaches from township 5 to township 27 and from range 1 co range 11, west of the fifth meridian. Its location is about fifty miles west of both Calgary and Lethbridge. Topography of the area ranges from foothill on the east to mountainous on the west. In this paper' the foothill region is considered to be chat which lies immediately east of the most easterly mountain ranges, such as Livingstone and Highwood. There are two principal coal mining districts in the area, one served by the main line of the Canadian ?Pacific railway and centring about Canmore, the other by a branch line of che same railway and centring about Bellevue, Blairmore, and Coleman.

Jan 1, 1949