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By Knud Sinding

Mining firms are widely criticised for their adverse impacts on the environment. At the same time many firms in the industry devote extensive resources, both financial and managerial, to the reduction or elimination such impacts. Very considerable improvements have been made, although these are sometimes overshadowed by a few high-profile accidents, such as the occasional collapse of a cyanide-containing tailings dam. In parallel, much effort is also directed at projecting a positive environmental image, as witnessed by extensive environmental reporting, both on paper and increasingly through web-platforms. Mining projects today almost invariably involve some form of environmental protection. In industrial countries regulations in this area are extremely stringent, as is enforcement. In less well developed countries, regulation and enforcement may be weaker, but firms are in many cases and for a number of reasons committing themselves to high levels of environmental protection, even if they might get away without doing so. Research in the area of environmental performance of mining firms has so far paid much attention to concepts such as sustainability indicators and the sustainability of individual firms. Given the still raging debates about the appropriate way to determine the degree to which any given firm is sustainable (Welford 1995) as well as the usefulness of what will in the final analysis be a value judgement, anyone on the sidelines of the debate will come back to the fundamental issue, how is knowledge that a particular firm has been judged ?sustainable? going to be made use of. This issue remains unresolved, which may explain the lack of progress in formulating a useful definition of a sustainable firm The question addressed in this paper is not so much about what firms are doing on the ground or in any particular case of environmental protection, but more in the subsequent use of these efforts - and by extension - on the overall direction of corporate environmental strategy. The fundamental problem facing all mining firms is that they cannot easily benefit from unilaterally reducing their environmental impact. The firm can of course avoid liability and keep a variety of stakeholders happy and hence experience lower costs of obtaining the [input] resources they need (in a broad sense, not just minerals), but this represents only part of the opportunities available form pursuing an environmental strategy (Reinhardt 2000). The other part, which may have an enormous potential, involves the concepts of competitor management and product differentiation. The logic of keeping stakeholders happy has been most forcefully argued by Pfeffer and Salanchick (1978) who link the behaviour of firms in all domains to their ability to obtain the resources they need, at a cost that is lower than it would otherwise be (Pfeffer & Salanccik 1978). Several varieties of strategy can be included under this heading, including cost reduction and risk management. The alternative logic is to convince customers that they want to pay more for minerals supplied by mining firm X or directly attributable to mine Y, or by making all mineral users pay more. These two strategies, which may be referred to as product differentiation and competitor management, respectively (Reinhardt 2000) are related to the demand side of mineral supply, whereas cost reduction and risk management are related to the supply side. Mining firms have not pursued the demand side very much, if at all. This is probably due to the extreme difficulty of moving mineral products, bulky and unglamorous as they are, away from their

May 1, 2003

By P. M. Shibley

"IntroductionMine drainage, surface. drainage and process liquors are the principal mine and mill effluents. The quantity and quality of these flows varies according to mineralogy, type and scale of mining, the process, tailing disposal, local ground conditions and climate.Typical contaminants remaining after solids sedimentation are colloidal or semi-colloidal particles, acids, alkalis, metals in solution, cyanides and thiosalts. Environmental regulations and guidelines have been issued in detail by the appropriate government agencies and will not be reviewed here. Revisions and additions are being made as our comprehension and abilities increase. Some contaminants of consequence have not been specifically regulated as practical treatment technology has not been identified. Thiosalts fall into that category as do the derivatives of the first stage of cyanide oxidation - cyanates.Most mining activities have present or foreseeable water treatment requirements. Because process economics can be adversely skewed by the environmental factor, the acknowledged objective of every operation must be to identify and anticipate those requirements.The evaluation and selection of water treatment techniques for mine-mill applications is complicated by the fact that most mine-mill effluents are high volume, dilute and chemically complex systems. Treatment processes applicable to most contaminants are: chemical or biological oxidation; neutralization and/or precipitation; liquid/solids separation. Other processes such as ion exchange, electro-deposition, foam fractionation, freeze crystallization and reverse osmosis offer the possibility of selective removal or concentration of contaminents. The latter tediniques, representing a slightly higher level of technology, are less suited to the large, low value flows usually encountered in the mine environment."

Jan 1, 1989

By Ki-Bok Min, Bona Park

"In spite of the applications of DEM models to emulate the elastic modulus, Poisson’s ratio and strengths of isotropic rock in laboratory scale, extensions to anisotropic rock and larger engineering scale still have many challenges to overcome such as robust verification and validation against observed field case. In this study, a discrete element modeling was performed in order to represent a transversely isotropic rock such as shale, and the upscaled model was applied to foundation and borehole problems using PFC2D. The applicability of the upscaled rock mass model was verified by an analytical solution. The DEM modeling of stress redistribution induced by an applied surface line load compares well with Boussinesq’s isotropic solution and anisotropic solution given by Bray. The borehole model with a circular opening under biaxial stress was compared with both isotropic and anisotropic solutions resulting in good agreement. The abilities of DEM model to investigate the micromechanisms accounting for complex macroscopic behaviors and to predict the macroscopic behavior are discussed.The results demonstrate that DEM modeling has the potential to be applied to anisotropic rock mechanics problems on larger engineering scales such as wellbore stability problems especially in shale formations. Furthermore, the effect of anisotropy modeled through this study may be able to explain failure behavior of anisotropic rock encountered frequently in real cases.INTRODUCTIONAnisotropy is prevalent in various types of rocks, especially in shale that contain a set of parallel bedding planes. These weak planes in various forms are sources of large deformation and low shear strength and contribute significantly to the anisotropic behavior of rocks (Amadei, 1996; Cho et al., 2012; Kim et al., 2012). As elastic and strength behavior of anisotropic rock is substantially different from that of isotropic rock, proper consideration of anisotropy is of great importance. There is extensive of experimental evidence showing the anisotropy of shale. Niandou et al. (Niandou et al., 1997) analyzed the plastic deformation and failure mechanisms of Tournemire shale were highly dependent on the orientation of bedding planes. Cho et al. (Cho et al., 2012) presented various deformations and strengths of Boryeong shale obtained from laboratory experiments. Fjaer and Nes (Fjaer and Nes, 2013) performed uniaxial and triaxial compressive strength tests using Mancos shale, and they observed that the shear sliding along the planes of weakness before the occurrence of a major failure can reduce the strength of anisotropic rock. The recent research has demonstrated that the anisotropy of rock is an important consideration in rock engineering."

Jan 1, 2015

By F. H. Samuel, J. E. Gruzleski, S. Valtierra, H. W. Doty, F. J. Tavitas-Medrano

319-type cast Al-Si-Cu-Mg alloys are commercially important due to their popular use in automotive applications. Artificial aging heat treatments are commonly performed in these alloys to achieve precipitation hardening and, therefore, improve their mechanical properties. The present work was carried out to investigate the effect of conventional (at a constant temperature, as specified by the standard T6 heat treatment regime), and non-conventional multi-temperature and interrupted aging cycles on the hardness, tensile and impact properties of two 319-type alloys (with and without Sr+ Mg additions). The results show that certain multi-temperature aging cycles have a more favourable effect in improving some mechanical properties than conventional cycles.

Jan 1, 2006

By H. Hejny

Given the current status of political discussion in Europe about raw materials issues, the sustainable development of the extractive industry and the reduction of its environmental and societal footprint are among the key topics in this discussion. In this context, the European Commission approved the EO-MINERS project (Earth Observation for Monitoring and Observing Environmental and Societal Impacts of Mineral Resources Exploration and Exploitation). The overall aim of EO-MINERS is to bring into play EO-based methods and tools to facilitate and improve interaction between the mineral extractive industry, authorities, and the society in view of its sustainable development while improving its societal acceptability. Developing generic, standardised and reliable EO-based products to monitor the environmental and societal footprint of mining projects is the way chosen by EO-MINERS to improve this interaction, along with the organisation of tripartite meetings gathering all relevant stakeholders. The project uses existing EO knowledge and carries out new developments on three demonstration sites (Sokolov lignite mining area, Czech Republic, Witbank coal field, South Africa, Makmal gold mine, Kyrgyzstan) to further evaluate and demonstrate the capabilities of integrated EObased methods and tools in monitoring the environmental and societal footprints of the extractive industry during all phases of a mining project, from the exploration to the exploitation and closure stages. It contributes providing reliable and objective information about affected ecosystems, populations and societies, to serve as a basis for a sound ?trialogue? between corporate stakeholders, governmental organisations and societal stakeholders. The project already developed a set of consolidated indicators based upon previous knowledge about mining-related issues along with interviews of national, regional, and local stakeholders. These indicators reflect known environmental and societal issues at mining sites as well as the interest of various relevant stakeholder groups. The process described in the EO-MINERS project ? policy assessment > indicator identification > choice of suitable EO tools able to serve monitoring task > monitoring by EO tools > making available objective information for fair dialogue among stakeholders ? is generally applicable to all stages of a mining project. The key to success will be the right choice of indicators addressing the problem and subsequently the right choice of suitable EO tools and finally the willingness of all stakeholders to find a common solution. To this end, the EO-MINERS project organises site-specific ?trialogue? workshops at each demonstrations site, which aim to provide relevant information in adequate quality to the stakeholders as common ground for discussions. Local stakeholders, including mining companies, regulatory bodies, and community representatives are invited to participate in these workshops where the relevance of the developed EO-based products to environmental and societal impact assessment will be discussed. The presentation will discuss results obtained during these trialogue workshops, as well as the success and difficulties and reluctances encountered. The project will further indicate ways and means how the EO products and other project results may be used for monitoring purposes in all phases of a mine.

Aug 1, 2013

By J. J. McDougall

Until quite recently, the coal in the Cape Breton field was won from comparatively thick seams with light cover, and from submarine areas, and the system of mining naturally followed was pillar-and-stall. This sytem permitted of cheap extraction, and enabled production from localities where other methods could not be employed to good advantage. Thus the pillar-and-stall system, applied to conditions as stated, justified its adoption. Our working seams today, however, are practically all under heavy cover, or are moving in that direction, and with this gradual increase in cover came the increased cost of roadway maintenance. At Princess colliery, the system of pillar-and-stall was followed until roof and bottom conditions became such that further operations were unprofitable, and the longwall method was then adopted as an economic necessity. This fact should be borne in mind when operating costs of both systems are being compared. The longwall method is not held as a cure for all difficulties of heavy cover, but through it these difficulties can be overcome with less expense than by pillar-and-stall. The longwall system of mining, strictly speaking, is one by which a seam of coal is totally extracted in one operation. There are, however, many modifications of longwall, and in some cases it is difficult to determine whether certain practices should be classed as longwall or pillar-and-stall, or a combination of both.

Jan 1, 1928

By Theo. Koulomzine

"The property of Consolidated Central Cadillac Mines, Limited, consists of 1,103 acres formerly held by Central Cadillac Mines, Limited, and Wood Cadillac Mines, Limited. Both mines have been partly developed to depths of 565 and 1,000 feet respectively, and from 1939 to 1943 they produced gold, with small amounts of silver and tungsten, having a total value of $2,208,528 from 377,489 tons of ore. The average grade of the ore was $5.85 a ton . Less than 10 per cent of the ore hoisted was discarded by sorting. New development work, carried out since the former Wood property has been purchased by Central Cadillac, has shown that the tonnage indicated by mine workings and diamond drilling exceeds 2,000 tons per vertical foot.The property lies between the claims of Kewagama Gold Mines, Limited, and Pandora Cadillac Gold Mines, Limited, and straddles the Cadillac 'break' for a length of nearly 1 ½ miles. The main workings are 1 3/4 miles east of the well-known O'Brien gold mine.GEOLOGYOutcrops are very scarce, with none at all of the most important horizons, so that the general geology shown in Fig. 1 is deduced mostly from underground workings and diamond drilling. Fig. 2 is a vertical cross-section and Fig. 3 a longitudinal section through the ore zone.The ore lies within a belt of Blake River volcanics which is approximately 600 feet wide and is flanked on the north and south, respectively, by Cadillac and Kewagama sediments. All the formations have a nearly vertical attitude. The Blake River belt consists essentially of well sheared volcanic tulfs, but associated with these in the northern part are a number of bands of iron formation and the central part, to a width of 100 feet, is occupied by talc schists, making the Cadillac fault proper. Intruding the volcanics south of the Cadillac shear zone are dykes of two types- finegrained aplite or quartz albitite, and porphyry; both consist essentially of albite and quartz and are distinguishable only by the grain size. They have the general east-west trend of the formations they intrude."

Jan 1, 1954

By I. Clauzier

"A new method of managing electricity to reduce costs andimprove profits is discussed. Before taking steps to better manage electricity, it is essential to understand the terms peak demand and energy and their effect on an electrical bill. Knowing how electricity is presently used in the plant is the important first step. This goes beyond knowing how much electricity is used at each time of day, the individual contribution of every plant process to the total plant load must be known. At this point, each process is ranked according to importance to production in order to identify possible savings opportunities. These improvements can then be implemented by simply improving operations or in some cases, through the use of an automatic control system. IntroductionIn today's competitive environment, controlling costs is becoming increasingly important. All costs associated with operation must be controlled in an effort to improve competitive position. Electricity is a cost component that can and should be managed.Although the term management can mean different things to different people, the intent is always the same: to make the best possible use of existing resources, whether labour, equipment or electricity.The simple approach to managing electricity presented in this paper consists of four steps.I. Understand Peak Demand and Energy. It is essential to understand the terms, peak demand and energy and their effect on your electrical bill.2. Know Your Present Electrical Use. The present use of electricity in the plant must be known. This goes beyond simply knowing how much is used at each time of day, to accurately knowing how each process is contributing to the total plant electrical load, and ultimately to the electrical bill.3. Identification of Savings Opportunities. With this information, energy savings opportunities for reducing the electrical bill and improving profits can be identified.4. Implementing Improvements. Having identified areas of potential savings, improvements can then be implemented in order of their significance. This could be a matter of simply improving operations, or in some eases may mean the use of an automatic control system.These four steps can result in significant dollar savings."

Jan 1, 1987

By M. Fiset, D. Belley

"In a country with a cold climate like Canada, the cost of replacing worn parts of snowplow equipment such as blades, is enormous. A great number of these blades, with different mechanical properties, are available, but few studies have been made to facilitate their selection according to the optimum ratio of wear resistance to cost. To attain this objective, laboratory tests have been developed to correlate test results with those obtained from various road service conditions. The test materials, 1080steel in different states, 1090steel and D2 tool steel were chosen to cover a large range of hardness as well as different microstructures. Comparison of the wear resistance of the test materials relative to a standard revealed, in general, a good correlation between the results of laboratory cement wheel tests and those from the road tests. Scanning electron microscope wear scars of laboratory and road test specimens were compared to determine if similar removal material mechanisms were active. IntroductionThe correlation between wear tests in service and those performed with the aid of laboratory equipment is of considerable interest. As a matter of fact, when correlation exists, it allows one to evaluate the performance of a material more easily and at a lesser cost.Several authors have been interested in simulating various wear circumstances, especially abrasive wear. In particular, the simulation of wear on implements working the soil, has been tried by several researchers. The test using the rubber wheel seems to be the one giving the best correlation if the soil is rather sandy and its moisture content is low.However, little work has been done concerning wear on the plates, skids and blades attached to trucks used for levelling and snowplowing; such equipment being used to keep roads clear in northern countries. Now each year, companies introduce new steels by claiming that the y are superior in performance to their predecessor s and invariably they demand a higher cost. The study presented here was undertaken with the goal of making a more judicious choice of these steels by simulating their behaviour in the laboratory. Moreover, the examination of abraded surfaces in situ and in the laboratory have also allowed us to compare the respective wear mechanisms."

Jan 1, 1988

By M. Ghiani, P. Carbini, R. Ciccu, C. Del Fà

"This paper is concerned with the problems inherent in the efficient and economical processing of the fine fractions of a coal from the Sulcis basin (Sardinia, Italy) whose characteristics are typical of low-rank coals occurring in the Mediterranean region. Three different techniques, based upon surface properties, are examined. Flotation can be very efficient from both a technical and economic point of view, provided care is taken in the modulation of the flotation pulp. Interesting results have been obtained with oil agglomeration and this method could be economically feasible. Finally, electrical separation has proven a viable technique, although it entails preliminary drying.Besides discussing the problems encountered in the experimental research, some significant results of general validity are also given. They demonstrate that cleaned products can be obtained with fairly interesting recoveries, thus opening the way to advanced research aimed at setting up the most suitable technique for industrial application. IntroductionAs a result of the oil crisis, which caused a major upset in world energy supplies, the last ten years have seen a revolution in the energy policies adopted.In particular, the status of coal, which seemed destined to decline in view of the availability of liquid fuel, has had to be re-examined. The need to meet energy demands under improved reliability conditions and controlled prices through a broader and more flexible diversification of sources of supply has evoked, especially in highly industrialized countries, a renewed interest in coal. The result has been a consistent increase in demand and production as well as investments in new mines and the reinforcement of the infrastructure.This turn of events has also lead to a re-evaluation of young low-rank coals, hitherto considered uneconomical and thus neglected, because of their low heat value. In fact these coals, which have a high ash content, may also be relatively highly contaminated with sulphur. The above drawbacks, which still today preclude the widespread use of these coals, are bound to create even greater problems in the future as increasingly restrictive environmental control imposes, without exception, recourse to cleaner fuels."

Jan 1, 1986

By G. W. H. Norman

The surficial Archæan rocks of the southern gold belt of western Quebec are constricted near Kewagama lake by granite masses to the north and south. This divides the belt into natural eastern and western parts. This paper deals with the eastern part, extending from Malanie to Haig township. In this section the Keewatin-Timiskaming rocks have a length of about 70 miles and end abruptly against garnetiferous gneisses of the Grenville terrain. In the western half of the section where exploration has been under way since the early twenties, there are sixteen mines that are or have been in operation, and eleven prospective mines. In the eastern half where exploration has been carried on since the early thirties, six prospective gold mines are under development, one· of which, Louvicourt Goldfields, is at the initial production stage. Of the sixteen properties in the western half that are operating or have operated, all, except the Golden Manitou, which is a base metal mine, and the old Green Stabell from which there was a small production of copper, produce gold. Of the eleven prospective mines in the western half nine have gold. New Bidlamaque has gold and copper and one, East Sullivan, has copper-zinc ore. Since production began in 1927 gold, silver, zinc, copper, and lead having a total value of about $10,000,000 have been produced from the mines of the eastern section of the southern gold belt of western Quebec.

Jan 1, 1954

By Robert D. Brown

"Important tax changes, many of them of direct interest to the mining industry, were contained in the budgets brought down by federal and provincial finance ministers across Canada this spring. This month, Tax Notes presents a brief summary of important tax changes introduced at the federal and provincial levels in the last few months.IntroductionIn the March 1980 issue of the CIM Bulletin, Tax Notes surmised that the short-lived 1979 budget proposals of the former Conservative government offered a unique glimpse of budgetary changes that might be unfolded in 1980. Scene II of this ""now you see it-now you don't"" drama opened on April 21, 1980, when Finance Minister Allen MacEachen, in an ""economic statement""' reintroduced a selection of tax proposals taken from the ill-fated Conservative' budget of December 11, 1979, but refused to bring forward major new proposals in tax and finance.Mr. MacEachen proposed a 5% surtax on federal corporation income tax to apply in the 2 years from January 1, 1980 to December 31, 1981, as a slightly modified version of the same surtax proposed by former Finance Minister Crosbie in his December budget address. Mr. MacEachen also reintroduced a number of technical amendments which would affect the taxation of mining income in certain instances. In addition, a large number of other tax proposals suggested in the previous Conservative budget were also reintroduced, although there are some notable omissions."

Jan 1, 1980

By C. Sideco

"Concentrate drying at the Sullivan Concentrator goes back to 1937 when the original coal-fired dryer was put into operation. This was a second hand 8' dia. x 56' long Struthers-Wells rotary dryer that came from the phosphate plant in Warfield, B.C.In 1962, replacement of the old dryer was seriously considered. The shell and the auxiliary drive mechanism were badly worn and needed replacing. In April 1963, the new 8' dia. x 65' long fuel oil-fired Struthers-Wells dryer went in operation at an installed cost of $174,000.In 1965, it was apparent that a major rebuilding of the dust collecting system would have to be done. A study was carried out and a Ducon Dynamic Gas Scrubber was installed. The system went in operation in November 1966 and has fully met expectations.In the same year, the zinc dryer was converted from fuel oil to natural gas. The conversion has resulted in savings in fuel cost of 12 to 15%.Frame No. 1Zinc Dryer PerformanceDryer Make - Struthers-WellsDryer Size 3/4 8' dia. x 65' long Drum Drive - 100 HPSpeed of Rotation - 5 RPMFeed Rate - 50-65 TPHFeed Moisture - 10-12%Discharge Moisture - 4-6%Dryer Inlet Temperature - 1600-1800°F Dryer Outlet Temperature - 200-250°F Stack Gas Volume - 25,000-40,000 CFNDust Collecting Efficiency - 99.75-99.98% Duet Loss in Stack - 50-300 lbs./day"

Jan 1, 1972

By S. Zador

"IntroductionIn the past decade, metallurgical and mining companies have shown an increased interest in the licensing of technology. When licensing technology, it is usually to the benefit of the parties, to have at least some of the technology to be licensed protected by a patent.This paper is intended to bridge the gap between the engineer in the field of mining, metallurgy and mineral processing who is interested in exploiting an invention commercially, and the patent agent or intellectual property lawyer whom he/she might retain to prepare a patent application and then prosecute the application to obtain a granted patent. It is also intended to encourage the inventor or a small business concern to consider the value of patents in the sale and licensing of technology. The lawyer may subsequently advise and assist the inventor in licensing his/her invention.A brief outline of some of the basic features of the patent system follows. The nature of the information, which the patent professional requires from the inventor to enable him/her to draft a patent application, will also be considered in general terms. Furthermore, various types of licenses which may be drawn up between a licensor of specific technical information and a licensee, will be listed and briefly discussed. No attempt, however, will be made to give a comprehensive and detailed account of the above aspects; the interested reader should consult legal publication and reference books, and patent professionals for further specific information.A granted patent is a document which describes an invention and how to practise it. The claims of the granted patent, figuratively speaking, fence off the intellectual property the inventor regards as his invention. The Commissioner of Patents, representing the Government, grants to the inventor or his assignee the exclusive right of making, constructing and using the invention, and selling it to others to be used, for a limited period of time, in exchange for disclosing the invention to the public. Thus, a patent prevents others from practising the claimed invention but it does not, necessarily, bestow the right to the patentee to practise his own invention. The term of a patent now in Canada and in most of the developed countries of the world, is 20 years from the date of filing the patent application. In the United States the patent term is still 17 years from the date of issuance of the patent. In Canada, the term was changed to 20 years in the new Canadian Patent Act which came into force on October 2, 1989. Any patent application filed prior to that date or granted before it, retains a 17 year life, commencing at the time of grant."

Jan 1, 1991

By S. Avalos, J. M. Ortiz, W. Kracht

Semi-autogenous grinding mills are intensive energy consumers. Current models base their energy consumption inference on operational variables and feeding ore characterization. While they provide adequate design guidelines, they are not suitable for real-time energy forecasting dealing with gaps in operational dataset and up/downstream process bottlenecks. This work explores the capability of Gated Recurrent Units to learn the semi-autogenous grinding mill consumption behaviour. Gated Recurrent Units are trained to forecast different time-support consumptions under a time-series operational dataset. The results show high performance on small supports (30 minutes) to capture local variability and long-trends while larger time supports (8 hours) can only capture time-trends but not local variability. The proposed technique seems promising for further research and implementation on real mine cases since the input variables are low-cost and easy to obtain. INTRODUCTION Current changes in the Chilean energy matrix (Román-Collado, Ordoñez, & Mundaca, 2018), from fossil fuels to renewable energies, have impacted different industries and particularly the mining sector. Solar energy incorporation into greenfield/brownfield projects will help reducing costs and will lead to rethink foundational paradigms (production and processing strategies) (Pamparana et al., 2017). Also, integration of new space-time predicting tools together with automated real-time updating models are some of the main challenges in the geometallurgical framework (Ortiz et al., 2015; van den Boogaart & Tolosana-Delgado, 2018). Those contexts encourage and demand the development of tools capable of predicting the energy consumed by mining systems, being comminution the greatest energy consumer with an average close to 50% of the entire mine consumption (Cochilco, 2013). In comminution, the semi-autogenous grinding mill (SAG) represents the largest energy consumer (~10 nominal each SAG). Theoretical and empirical energy consumption models (Jnr & Morrell, 1995; Morrell, 2004; Silva & Casali, 2015) base their inferences mainly on feed/product size distributions, SAG sizing, bearing pressure, feed hardness, water addition and grinding charge level, and commonly assume steady-state and work isolated from up and downstream processes. While those techniques provide adequate design guidelines, they are not suitable to predict hourly, daily or even weekly energy consumptions on interconnected comminution circuits where upstream/downstream bottlenecks lead SAGs to operate below designed regimes. Forecasting energy consumption is required by short-term energy management, medium and long-term planning energy consumption, designing the nominal capacity of renewable energy sources, among other. Also, when models are input-sensitive and some of those input measurements are expensive and/or time consuming, model robustness suffers when real-time predictions are required.

Jan 1, 2019

By L. T. Raevskaia

We discuss the stability problem of a piston of the reversible axial-piston pneumatic motor called DAR-14M. We performed the full analysis of stress and deformation characteristics of the piston near a resonant frequency with the help of FEM ANSYS. We estimated the own frequency of the piston analytically for the given motor, this estimate was confirmed numerically in the model analysis FEM ANSYS. It was also shown in harmonic analysis that loaded piston end behaves very different in comparison to the unloaded end. As expected, maximum deformation was found in the area of the holes of the bearing shaft, indicating an optimization necessary in that region of the motor.

Aug 1, 2013

By W. L. Stuewe

The Dominion Steel and Coal Corporation requires enormous quantities of bricks each year for its Sydney steel plant operations. Clay brick of all types are purchased, while silica brick is made in the Company's plant at Sydney. A description of this plant was given in a paper presented by H. B. Gillis and F. C. Morrison at the 1938 Annual General Meeting of the Institute. The rock used to make silica brick was for years obtained from a quarry at Leitches Creek, about eighteen miles from Sydney. Due to the gradual deterioration of this deposit, the Corporation was forced to look for other sources of supply. In 1945, the problem was presented to the Nova Scotia Department of Mines and, through the efforts of Dr. A. E. Cameron and Mr. J. P. Messervey, an examination was made of a silica-rock deposit some six miles northwest of Yarmouth, N.S. Preliminary samples proved satisfactory, and arrangements were made with the Department of Mines to ship to the steel plant at Sydney a fifty-ton car load for the purpose of further testing. Brick made from this sample shipment stood up very well in the furnaces. At the same time, two hundred and fifty tons of silica rock from a deposit at Lac Bouchette, Que., were purchased from the Industrial Silica Corporation, and brick made from this rock also was found suitable for our requirements. Comparative transportation costs, however, led to a decision to open the Yarmouth deposit. The silica rock, or quartzite, of this deposit outcrops at Chegoggin point along what is known as the 'Pembroke shore', a northerly trending section of the coast-line at the extreme southwest of the Province, in Yarmouth county. The country here is fairly flat, with elevation averaging about twenty feet above high tide, and is for the most part mantled by a growth of brush and some scrub trees, chiefly small fir. Bed-rock is generally concealed beneath three to four feet of clayey soil, but scattered outcrops of the quartzite indicated that a band of this rock, some 260 feet wide, extended inland in a northeasterly direction from Chegoggin point at least to Utleys lake, a distance of about three miles.

Jan 1, 1947

By I. Kylmakorpi

In non-ferrous metal smelting, when the concentrate entering the furnace contains high levels of moisture, energy requirement for heating and drying increases and large volumes of exhaust are produced. To solve this problem, rotary dryers and flash dryers using direct heating, and also steam dryers using indirect heating have all been used for drying concentrate. The focus of this paper is to present the development and current applications of the Kumera Rotary steam dryer. The advantages of this technology are numerous, including reduced heating requirements, environmental friendliness, operation reliability and minimum maintenance needs; making it a top choice for drying concentrate.

Jan 1, 2008

By Frank Lemy

This paper presents an application of digital face mapping in an underground mine. Based on photographs it was possible to construct discontinuity maps, which were used to characterise the rock mass. The results were compared favourably with values obtained through scanline and area sampling mapping for the same site. The case is made for digital mapping as a safe, fast, and efficient way to characterise rock mass structure for engineering purposes.

May 1, 2001

By A. F. Laurin, A. L. Dorr

"Because of its wide areal extent, its numerous lithological facies and its high degree of metamorphism, the Quebec portion of the Grenville province has only partly been explored and prospected. Rock types that are economically among the most interesting in the Grenville are those of mafic and ultramafic compositions, because of their great potential for coppernickel and chromium-platinum. The peculiar mode of occurrence and the distribution of these igneous masses in which copper-nickel mineralization is known to occur indicate' two common geological features: (1) aerial photographs and/or topographic maps strongly' suggest close spatial (and possibly temporal and genetic) association of most of these mineralized mafic and ultramafic intrusions with circular structures; (2) when plotted on a large-scale map comprising the Quebec portion of the Grenville, these circular structures fall along two lines which could correspond to major tectonic features. Even though the genetic links among the mineralized mafic-ultramafic masses, the circular structures and the linear features are not yet fully understood, their associations are believed to be empirically valid and should therefore be used as geological tools by those interested in exploring the Grenville for copper-nickel and possibly chromium-platinum deposits. It should be noted that these mafic and ultramafic bodies do not appear to be spatially related to anorthosite complexes."

Jan 1, 1971