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By A. Tylczak, C. Norman, C. Shook, S. Loif

"There are a lot of good reasons to manage energy use at mining operations. Optimizing process energy use reduces operating costs. Tracking energy use can help identify unplanned process changes or malfunctioning equipment early, which allows problems to be corrected promptly.Sacré-Davey Engineering in Vancouver has performed over 50 Energy Management studies for various industries including: mining, pulp and paper, oil and gas, etc. Energy Management programs can be used to identify energy reduction opportunities, assess project feasibility, complete equipment selection trade-offs, as well as to monitor and manage energy costs. Benefits of energy management programs are reduced energy costs, reduced maintenance, and increased plant automation. Additionally, energy management can provide access to utility incentive funding and quantify savings which can greatly improve the return on investment of potential projects.Energy management studies are funded by many Utility programs across Canada. There are various programs available for existing plants energy audits, project feasibility studies, new plant design reviews and energy monitoring and targeting, etc. There are capital incentives available which can significantly reduce payback period.This paper discusses how energy management can be used to support mill/mine operations groups, maintenance programs, as well as expansion or green field projects. This paper will also provide an overview of Canadian Utility companies programs and how they can assist mining companies.IntroductionThere are a lot of good reasons to manage energy use at mining operations. Optimizing process energy use reduces operating costs. Tracking energy use can help identify unplanned process changes and identify malfunctioning equipment early, which allows problems to be corrected promptly."

Jan 1, 2015

By Mark W. Booth

THIS paper deals with the subject of inbye power as the mechanical . engineer sees it, and invites discussion, particularly from the electrical engineer. At the outset, it will be necessary to clear the ground a little by some definite statements. In this question of compressed air versus electricity for the transmission of power and driving of machinery in underground workings, we must see that there are definite fields that compressed air on the one hand, and electricity on the other, can fill to much greater advantage than the other, and in which there can be little or no direct competition, at least for the present. It is under conditions where these fields overlap, and as to where the line must be drawn between the two, that the respective merits of each must be considered. Steam was the first means used to transmit power from the surface of a mine to drive underground machinery, and so long as distances were short and means possible to ensure fairly efficient use of the steam, and where the fire hazard was not in evidence, it gave fairly efficient service. I have in mind an instance during my own connection with the mines-a duplex pump at the shaft bottom at Princess colliery, driven by steam, and which used the steam compound and condensing; and, but for the mechanical difficulties, it was a not inefficient proposition. The steam was taken direct from the surface boiler-plant through a line down the shaft, and used directly at the pump, being in effect a straight conversion from coal to steam to work done. It was the mechanical arrangement, and failure of the pump in that direction, that led to its removal and replacement by something better in the way of an electrically driven turbine pump. Given modern mechanical arrangements, such as a steam-turbine drive on a high-speed turbine pump, and all other parts made in accordance with best practice in the art of steam generation and use, a steam-driven unit fully as economical would have been obtained. But the central electric supply station, and all that that means or promises (not always the same), turned the scale against steam.

Jan 1, 1936

By Robert B. Parsons

"This month, Tax Notes focuses on two features which can potentially ""dress up"" a new issue of common shares to make the shares more attractive to investors. Attaching warrants to a share issue is a relatively common practice, and recent years have seen an imaginative variety of different kinds of warrants, some of which can be subject to somewhat different tax treatment . A less common financing strategy which certainly deserves some consideration involves the possibility of utilizing ""Share Purchase Tax Credits "" in conjunction with a new share issue.IntroductionPrevious subjects covered in Tax Notes have dealt with flow-through shares and other tax angles which can make equity issues more appealing to potential investor s. Two other techniques which can add zest to a new stock issue involve the utilization of warrants and ""share purchase tax credits"" (or SPTCs). This article takes a brief look at the better known subject of warrants and the lesser known matter of SPTCs.Of course, this paper presents only a relatively general summary of the income tax implications of warrants and SPTCs, and is not intended to be a definitive commentary on all of the detailed and complex tax issues that might be relevant in the circumstances."

Jan 1, 1985

By A. Esterhuizen, S. Essack, H. Joubert, N. Fowler

Tenova Pyromet has developed innovative technologies for copper smelting and electric slag cleaning furnaces. Based on client feedback and requirements, innovative designs have been developed to address key design areas and improve furnace reliability, operability and hygiene. These developments include the NovaLance™ lance system to prevent lance bending on top submerged lance furnaces, the SlagFlo™ slag tapping flow control device to better control bath levels and tapping rate for granulation, and an electrode seal for improved sealing directly onto the electrode casing to allow water-cooled electrode components to be located above the furnace roof. The potential application and benefits of these innovative designs are discussed. INTRODUCTION Tenova Pyromet has a long history in the engineering and supply of innovative electric furnace and related equipment for the base metals and platinum industries. Recently Tenova Pyromet has used its furnace equipment design experience to engineer innovative solutions for top submerged lance (TSL) furnaces, and potentially other furnace technologies. These equipment design solutions are developed to address specific operating challenges and operator requirements. Three of these innovative equipment developments are discussed in this paper. First the NovaLance™ lance technology to prevent lance bending during operation in TSL furnaces, such as used for primary copper smelting, is described. Lance bending has been identified as a significant problem for TSL furnace operators as it causes down time and affects furnace availability. The SlagFlo™ device to control the slag flow rate during tapping has been developed based on specific requirements in the mineral wool industry. The SlagFlo™ device can be used to control slag bath levels in primary smelting, converting and slag cleaning furnaces for base metals including copper. In addition, it can be remotely activated for the safe closing of slag tapholes located upstream from a water granulation system. Finally, Tenova Pyromet developed an electrode seal that seals directly onto an electrode surface. This is a special requirement related to base metals and platinum electric smelting and slag cleaning furnaces where furnace operators prefer to keep the water-cooled electrode equipment above the furnace roof. The seal can be used to seal directly onto the potentially hot and uneven surface of Söderberg, pre-baked and graphite electrodes.

Jan 1, 2019

By D. Schleiss

Reduced access to knowledgeable workers is creating challenges for operations. We are doing more 4D Operations - dirty, dull, dangerous, and distant. Personnel costs in these environments are high, and it is not always possible to get the people where you need them. Integrated Operations is a strategy to integrate people, process, and technology for faster and better decision making. Adopting an integrated operations approach can help to relocate personnel, improve collaboration, and align objectives to deliver reduced costs and improved performance. In this paper, the authors will highlight the required infrastructure to enable an Integrated Operations platform. Key decision points for enabling this technology for both Greenfield projects and existing mines will be discussed. Furthermore, the benefits and improved return on investment that result from deployment of an Integrated Operations strategy will be presented.

Jan 1, 2014

By J. R. Kadambi, E. Kucukal, J. Furlan

"Hydrocyclone separators are used in various industrial applications, including mining milling and tailings systems, in order to separate or classify solid particles and liquid droplets from multiphase systems. The flow within a hydrocyclone commonly used in the mineral processing industry was investigated numerically and experimentally using Particle Image Velocimetry (PIV) and refractive index matching techniques. The computational simulations were performed using a commercially available CFD package, STAR CCM+. Two turbulence models were used in the numerical calculations: the k-? model and the Reynolds Stress Model (RSM). In both cases, the first order discretization scheme was unable to resolve the flow characteristics accurately due to the high levels of numerical dissipation. PIV measurements were taken at various spatial locations along the cyclone. Both the numerical simulations and PIV data demonstrate that tangential velocities tend to increase when going radially inward from the cyclone wall towards the vortex finder, and reach a maximum value before they begin to decline rapidly and eventually become zero at the wall. The results also demonstrate the utility of non-axisymmetric approaches in cyclone flow simulations for a greater understanding of the fluid mechanics. The computational results were validated globally using pressure and flow rate readings at the boundaries and locally by comparison to the PIV velocity vector maps and profiles. The comparisons demonstrated good agreement between the two models.IntroductionHydrocyclones are devices used to separate and classify solid particles or liquid droplets from liquid-solid or liquid-liquid systems. Versatile in application, they have been widely used in many industrial applications including the food, oil, power generation, chemical and mineral processing industries since 1891, when the first hydrocyclone was introduced by Bretney (Park, 2003). Hydrocyclones have a relatively simple design with no moving parts, which leads to an efficient separation process."

Jan 1, 2016

By C. M. Anson

This paper describes the progresses used in the manufacture of steel wheel-centres, tyres and axles at the works of the Commonwealth Steel Products Co., Newcastle, N.S.W., Australia. The plant is adjacent to the Northern railway and consists of three main buildings, namely: the foundry, the forging and rolling shop, and the machine shop. The foundry contains a 6-ton Heroult electric furnace, together with all necessary mechanical appliances for moulding. Reheating furnaces, steam hammers and tyre rolling mill are installed in the forging shop. The machine shop contains lathes, boring machines, and hydraulic presses. Until this plant commenced operations all wheels used in Australia were imported, previ.ous to the war, from England and Germany, and latterly from England only. Besides being of great benefit to the country in that there is now a domestic source of supply of these articles, there is also the advantage of retaining the home market; and in addition, a small portion of the population are now engaged in highly technical occupations requiring a great degree of skill. The plant began to operate in October 1919, and by 1921 was in a fair way to meet the domestic demand for those articles of railroad equipment which it manufactures.

Jan 1, 1925

By Jean-Jacques Bouillon, Michel Jébrak, Stephane Faure

"Le gisement polymétallique (Cu-Zn-Au-Ag) des Mines Selbaie est forme par un réseau de filons encaisses dans une séquence de pyroclastites felsiques du sill on Harricana-Turgeon. Les minéralisations sont encaissées dans le tuf de Selbaie, situe sous une épaisse séquence d'ignimbrites Iitées. Ce gisement se distingue des autres gites archéens par une chronologie atypique des minéralisations: les veines de chalcopyrite, de sphalérite et de galène recoupent un amas exhalatifpyriteux stérile. Un vaste halo d'altération hydrothermale a chlorite et mica blanc est associe à cette minéralisation.La mise en place des veines minéralisées est associée à une phase d'extension NNW-SSE. Le complexe volcanique subit, par la suite, trois phases de déformation. Une compression, orienté N-S, développe une schistosité à peine pénétrative et un réseau de fentes de tension. Une réorientation des contraintes locales selon une direction WNW-ESE conduit au chevauchement de I' écaille d'andésite et de tonalite de Brouillan. Un réseau conjugue de failles normales cassantes est associe au relâchement des contraintes."

Jan 1, 1990

By T. P. R. de Jong, H. Harbeck

"This contribution reports recent mineral sorting experience and lists the opportunities of the newest generation of automatic sorters with a special focus on electromagnetic detection and Xray transmission. With the available sensor resolutions and actuator systems that are available today sorting of minerals down to 2 mm size and up to 250 mm lump size is technically feasible. In industry, ore as well as coal is still hand-picked and current automation potential only utilised in a handful of specific applications. Recently a number of technological developments took place that may increase sorting potential, save mill costs and lead to lower overall tonnage costs.They are:??High speed and high resolution sorting systems based on X-ray transmission imaging??High speed on-line image processing and further development of advanced data processing??Modular multi-sensor automatic sorting units (using one or more sensors such as colour, electromagnetic and X-ray in a single device)??Sensitive electromagnetic sensors for sorting based on differences in magnetic susceptibility and electric conductivityThe above enables compact dry separation, insensitive for moisture fluctuations and at high separation sharpness, as well as “electronic” high gradient magnetic separation for larger particles. Besides conventional X-ray transmission (XRT), dual-energy XRT (DE-XRT) is now being redesigned to meet the requirements of the mining industry. The mentioned technologies provide automatic dry separation of minerals and rock as alternative for conventional processing."

Jan 1, 2005

By Hans Chr Andersen

Almost every form of iron ore and carbon material has been used as a raw material in the production of pig iron in electric reduction furnaces. Experience derived from the operation of the large 33,000-kva. Tysland-Hole furnaces, however, indicates that production results are very much influenced by the raw material conditions. The author presents the principle pattern of the metallurgical structure of the interior of an electric pig iron furnace. On the basis of this, he discusses the variations of electrical and metallurgical conditions for the process which will take place with changing raw materials. The formation of a coke bed underneath the electrodes, and its influence on the furnace operation, is illustrated. Quality and grain size of the coke added to the charge will influence the build-up of the coke bed and will thereby also affect the electrical re-''Elektrokemisk A/S, Oslo, Norway. resistance and reduction potential in the furnace.

Jan 1, 1963

By R. J. Enright

Eight mines in canada and three in Australia were visited between September 1987 and Februacy 1988. All mines had encountered problems with sulphide dust explosions and had introduced defence mechanisms to prevent or limit the extent of these explosions. Techniques included dispersion of limestone by various methods, use of water foggers, placing of water and inert stenuning in blast holes, and removal of settled dust to prevent secondary explosions. The techniques were evaluated and it was concluded that certain practices should be modified or discontinued as they were of little value in preventing dust explosions.

May 11, 1988

By H. P. Jacobi

"The last 25 years have seen tremendous economic pressure placed upon the base metal processor. Industry has responded with technological innovations that have contributed to significant reductions in capital and operating costs. Major changes in processing machinery and philosophy are highlighted for the main unit operations of a base metal mill. Changes in our attitudes on what is environmentally acceptable are also discussed.INTRODUCTIONNewton's law of motion paraphrased states that nothing will change unless there is a pressure to do so.Aase metal processing as a primary commodity related industry has been under severe economic pressure over the last 25 years. This has been brought on by over capacity from new operations in the L.D.C. 's, through material substitution in a host of traditional base metal applications and generally reduced world-wide economic activity. In addition to shrinking markets our collective environmental consciousness has raised effluent standards and workplace hygiene and the employee's as well as government's economic expectations of how much ought to be derived from ''nature's riches''.Industry has responded with technological changes which, it was hoped, would counteract the cost squeeze in which it found itself.I would like to briefly enumerate the major changes, as I see them, that have taken place in the main unit operations that form the normal processing chain for base metals.While the following paper will mention several brands of products, I would like to emphasize that these are the ones that I am most familiar with and is not to say that they are the only manufacturers which have contributed to changes. In fact it ls fair to say that all makers of mining and processing equipment have made improvements to their products, to a greater or lesser degree; they have had to, to still he in business in 1986."

Jan 1, 1987

By Joseph L. Fournier

Suncor Oil Sands employs delayed coking technology in converting bitumen into synthetic crude oil. Currently up to 10,000 m3 of delayed coke (coke) is produced per day as a byproduct of the upgrading process, of which up to 9,000 m3 per day is placed in dry storage on Lease 86/17. A review was completed to examine the case history of leachate potential experiments from the dry storage of coke and the environmental relevance of coke leachate studies conducted over the past decade. The review included an evaluation of the potential impacts of environmental conditions within the location of coke storage, including precipitation pH, as well as daily and annual ozone trends. Coke leachate potential has historically been characterized using standard leachate testing protocols (i.e., TLCP, SPLP) together with other studies that have employed strong acids and oxidizing agents in the extraction fluids. The present paper highlights prevailing conditions in the Athabasca Valley air-shed with emphasis given to ambient ozone (oxidizers), as well as precipitation pH and acid input deposition rates, and will demonstrate that TCLP / SPLP tests lack the intended environmental relevance relative to the conditions under which coke is stored.

May 1, 2011

By Elaine Ellingham, Francis T. Manns

"Abstract -The Orostar and Scadding were two small gold mines owned and operated by Orofino Resources Limited. Conventional statistical treatment indicates an identical arithmetic mean grade of 0.22 oz/T Au for both mineable reserves. Further, the deposits are both shown to have cut weighted average reserve grade of 0.21 oz/T. Orostar mined out at 0.206 oz/T and Scadding at0.156 oz/TAu . The combined exploration and development database contained 1394 fire assays, more than enough for statistical confidence in a normal distribution. Therefore this study was initiated to determine, if possible, why the mill head grades were lower than the averages and to experiment with several methods to determine whether a reliable statistical mill head grade estimation method would emerge. Despite the identical reserve grades, distinct differences in the grade distribution histograms are present. By studying the arithmetic and log-normal grade distribution s, with some attention to South African practices, this paper reports on those differences which may account for the considerable divergence in the mill head grades. Furthermore, this study casts considerable doubt on the industry standard method of cut weighted averages.The global mill head grades of the two deposits have been derived from the arithmetic average grades by graphic means. This precise method of mill head grade prediction, if applied to complex orebodies, could permit selective grade control and result in direct cost savings by allowing the operator to detect false value stopes, benches or levels and emphasize reliable regions of not only gold mines, but also uranium or base metal deposits."

Jan 1, 1992

By A. I. A. Salama

The CANMET Western Research Centre (CWRC) has developed a hydrocyclone model simulation of dewatering and fine particle separation circuits. The simulation is based on an existing empirical model. Utilizing a cyclone manufacturer’s published data, some modifications have been developed and integrated into the model. Feed stream characteristics, cyclone mechanical dimensions, and operating conditions are used in the CWRC modelling simulation. The computer results are presented in 3D graphs and corresponding 2D maps showing the cyclone mass recovery, percent solids by mass in underflow and overflow, and cut size as functions of the cyclone apex diameter and cyclone throughput (i.e., inlet pressure or pressure drop). Results of the computer simulation have been used in the economic feasibility and design of several dewatering circuits in oil sand plants.

Jan 1, 2003

By L. Betteridge, A. Marks

"An OK 300 cu. ft. Skim - Air cell was installed at the HBM&S concentrator in Flin Flon in 1987. Since that time, 3 additional OK Skim - Air cells have been installed in HBM&S concentrators. The cell treats a coarse 70% solids slurry with a residence time of 2.5 minutes. The product from the cell (a unit cell type application) is a final grade copper concentrate with high precious metal values. Since its installation, the cell has improved gold recovery by 10 - 15%. Process variables such as circulating load, pH, froth depth, feed size, and reagent additions all have an effect on the operation of the cell. Maintenance on the cell has been minimal. Initial operating problems involving level control have been significantly reduced and operations are now relatively trouble free. Although very successful at Flin Flon, site specific operating circumstances will determine the suitability of this cell. INTRODUCTIONHudson Bay Mining and Smelting operates four concentrators in Northern Manitoba. Three treat copper-zinc ores, the fourth mills a copper-nickel ore. The Flin Flan concentrator operates two circuits in parallel which treat copper and zinc ores from the Trout Lake and Callinan mines. Both circuits in the Flin Flan mill have Skim-Air cells integrated into the grinding circuits.The Trout Lake cell was installed first and had a payback period of a few months. Required modifications to the cell were made to enhance its performance. These included changing the discharge valve size, tuning the level controller, and installing an insert into the rubber valve sleeve to increase its wear life. The payback period on the Callinan cell was significantly reduced because these modifications were completed prior to its installation.The cells produce a final grade copper concentrate and since their installation gold and silver recoveries to the final copper concentrate have increased significantly. Operating parameters such as coarseness of cell feed dictate the metal recoveries and froth depth determines the selectivity of the cell and therefore the grade of the concentrate.The Skim-Air cell can be suitable in applications where a final product is generated. However, when a bulk concentrate, which requires further separation, is produced, the coarseness of the product may not make it amenable to conventional flotation.The Flin Flan mills Skim-Air cells have worked exceptionally well with little maintenance required."

Jan 1, 1991

By J. K. Armstrong, C. Feyerabend

"As mines are constantly growing and expanding, so do the challenges for emergency response teams. They have to keep up with the pace set by current and future production techniques. Although mines have now reached depths of several kilometres and their dimensions and complexity are that of an entire city, mines rescue still must be able to reach the most remote areas within the mine in a swift and safe manner. The duration of breathing apparatus and physical human capabilities are limitations. Therefore, alternative methods have to be explored to extend the time under oxygen for mine rescue teams without putting additional stress on the team members. To address this global trend, Dräger, Goldcorp and PAUS have partnered to develop a mine rescue vehicle that allows mine rescue teams to travel for an extended period of time through a contaminated atmosphere without the use of breathing apparatus, thus extending the range of their mission. By applying currently available techniques, the safe expansion of mine production can be ensured, giving mine rescue teams the ability to respond to accidents in a safer and faster way. INTRODUCTION With the reduction of easily accessible natural resources, there is a global trend toward searching for higher ore grades underground and/or continually expanding mines underground to extend their lifetime. While in some areas this trend has just begun, in other countries mines are reaching depths or horizontal dimensions that pose extreme challenges (Codelco, 2016). These challenges include safety relevant topics, such as rock stability, heat and seismicity, but also more basic issues such as distances to the working face, which can become crucial considering the cost to develop a new shaft or decline. To overcome this, there is a growing interest in collaboration among various stakeholders to drive the development and support of deeper mines and tackle the complexity of underground mining. This is evidenced by the fact that several industry and research groups and networks have formed, e.g. the I2mine project in Europe and the Ultra-Deep Mining Network by the Centre for Excellence in Mining Innovation in Canada. Due to commodity pricing and the trend toward renewable energy, metal/non-metal mining will be the driving force behind this development."

Jan 1, 2019

By W. R. Cowan

The Caledon Outwash is a large deposit of glaciofluvial gravel and sand located 55 km north west of down town Toronto. For the most part it was laid down in a meltwater channel fronting the Paris Moraine about 14,000 years ago. Applying the braided bar model of Eynon and Walker (1974) the principal facies present are imbricated coarse gravels (bar corefacies); crudely stratified, imbricated bar top sandy gravels; and trough crossbedded side channel sands and gravelly sands. Of lesser importance are crossbedded bar front gravels, shallow braided stream facies gravels, and stoss side facies sands and pebbly sands (rare). Lithologically these deposits are characterized by FIGURE I. Geological relationships of Caledon Outwash. Industrial Minerals in Canada up to 95% Ordovician limestone and siltstone in the gravel fraction. A siltstone content of up to 34% requires that beneficiation be carried out for the production of better quality aggregates. Resources remaining are estimated to exceed 500 million tonnes in 3000 ha of the most suitable part of the deposit. Present production is about 4.5 million tonnes per year, shared by several producers.

Jan 1, 1984

By R. E. MacAfee

THERE have been great changes in the design, capacity, and pressure of steam generating units over the past fifty years. If we go back as far as 1890, the plants then existing were largely horizontal return tubular boilers, hand-fired, with the boilers supported on the brick sitting which was com-posed of red brick with, probably, a refractory lining one brick thick in the combustion chamber. About this time, the water tube boiler began to supplant the H.R.T. boiler and, where new plants were being constructed of any size, water tube boilers were largely installed. In those days, say from 1890 to 1905, a 250 h. p. water tube boiler was considered a large unit. These boilers were largely the straight tube type and were set with the first row of boiler tubes three to six feet above the grates. The brick setting was a combination of red brick and fire-brick. The fire-brick lining in the furnace proper was usually 9 in. thick and in the first pass 4 1/2 in., while the rest of the setting was entirely red brick. These units were largely hand-fired and were expected to produce about 100 per cent rating as a maximum. It may be well at this point to define rating, which is the evaporation of one boiler horse power per hour by each ten square feet of heating surface in the boiler. A boiler horse power is the evaporation of 34.5 pounds of steam from and at 212°F. Consequently, a boiler containing 2,000 square feet of heating surface is rated at 200 h. p. and the evaporation at 100 per cent rating is 200 X 34.5, which equals 6,900 pounds of steam per hour from and at 212°F.

Jan 1, 1939

By Dominic Fragomeni

"The mineral processing industry has had a long history of innovation that is recognized but not often celebrated. These include significant advances in mineral measurement, testing, comminution, mineral separation and process control technologies that have transformed mineral assemblages into ore.This presentation presents some of the major mineral processing innovations and the impact they have had on our industry. As we look to the future, it is critical that we innovate and change. We will explore some examples of the next developments and how they can be catalyzed in the face of risk management, lower metal price cycles, resource constraints, inertia and the challenge of short term value delivery."

Jan 1, 2017