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By V. Prasad, A. Afacan, K. Popli, S. Dubljevic

Froth flotation is one of the most common and widely used separation processes in the mineral processing industry; however, its complexity means that complete understanding of the process has not yet been achieved. A dynamic fundamental model is needed to enhance the understanding of the process and to improve process control. It is challenging to capture all the phenomena involved; hence, we propose a multiscale modeling approach with a framework ranging from macroscopic (equipment scale) to microscopic (attachment, detachment) models along with distribution models for ore particle sizes. Real-time froth properties are obtained using a vision-based sensing system. These measurements can be used for developing a soft sensor for grade using statistical methods such as PCR (principal component regression) and PLS (partial least squares) regression. The fundamental model is updated in real-time using extended Kalman filtering. Attachment dynamics are studied for different particle size distributions. The modeling and soft sensing is tested on batch flotation cell for the pure mineral galena with different particle size distributions using Xanthate and MIBC as collector and frother, respectively. The model, online measurements and soft sensor are useful in developing monitoring methods for froth flotation.

Jan 1, 2015

By Richard Wells

Peabody Energy is the largest pure-play publicly traded coal company in the world. We have been in business 129 years and like most of the coal mining companies in the United States, since 1969 the majority of our safety improvement efforts had been driven by compliance with the various versions of the Federal Mine Safety and Health Act and the supporting federal regulations. In 2004 Peabody Energy management came to the understanding that in order to achieve our goal of zero incidents, that focus must change. This paper will describe the elements of the journey we began at that point to make the transition to a behavior and systems-based approach to safety management and our efforts to win the minds and hearts of our employees. This journey is undertaken with the goal of making safety truly a way of life for all Peabody Energy employees.

Aug 1, 2013

By M. G. Manzone

Approximately two-thirds of the annual 210,000 tons at copper refined by AMAX Inc. at the United States Metals Refining Company in Carteret, New Jersey, comes from a wide variety of copper scrap ranging from low-grade smelter scrap to wirebar-grade material. The equipment and methods used to effect such large-scale metal recycling in an urban area and the measures taken to collect and recover metal values from smelter and refinery byproducts while protecting the environment from pollution are described and discussed.

Jan 1, 1977

By Edward R. Lauer

Energy conservation is an integral part of Canada's energy strategy. We must pursue conservation and energy management vigorously if we are to remain competitive in domestic and world markets, and minimize our reliance on external energy sources. Energy management in industry is discussed from three viewpoints: (l) as a means of directly improving profitability; (2) as a major factor in the supply picture; and (3) as a significant influence on Canada's balance of payments and over-all economic well-being. The Federal role in promoting a voluntary industrial energy conservation program is described.

Jan 1, 1977

By J. R. Fisher

"Uranium may be leached to some extent in situ from the Blind River conglomerate uranium ores by using the products of bacterial activity from the bacterium Thio-bacillus ferrooxidans his paper describes some of the laboratory techniques used to investigate the characteristics of the bacteria, and to utilize their properties in uranium leaching. The application of some of the laboratory results underground at the Milliken mine of Rio Algom Mines Limited are de-scribed, along with the method of uranium recovery from the mine waters."

Jan 1, 1966

By E. Brzychczy

Artificial intelligence techniques are ever more frequently implemented in the modern world. One of their numerous uses is supporting enterprise management. Intelligent techniques and intelligent information technology (IT) systems can be implemented in mining-related issues as well. The author of this article concentrates on supporting the process of planning mining operations by intelligent systems and techniques. The author also underlines the importance of knowledge accumulation in a mining enterprise (especially tacit knowledge) as well as its efficient storing and using. Additionally, the author provides a short description of characteristics of intelligent IT systems and indicates their capabilities in planning mining operations. She presents two solutions, namely: an advisory system which supports the process of planning preliminary works and exploitation works in hard coal mines, and a method of modeling and optimizing mining operations. Finally, the author indicates a few possible future development trends of intelligent systems - the intelligent systems of decision support.

Aug 1, 2013

By A. P. Craig

"I HAVE BEEN looking forward to addressing this particular audience about Trans-Canada Pipe Lines because you men, more than most, understand the problems of the pioneer. Trans-Canada Pipe Lines qualifies as a pioneer on two counts: it is certainly pioneering a completely new industry in Canada -the long-distance transmission of natural gas -and it has at least a few of the problems that are expected and normal to any pioneering venture.This morning, I’m going to try to give you a sketchy picture of our project and a brief report on its current status and our progress to date; and then a broad picture of Canadian markets for natural gas.The physical characteristics of the Trans-Canada Pipe Lines project have been discussed so often that I am not going to take the time today to quote a lot of statistics on pipe sizes, miles, tons of steel, etc. Suffice it to say that this project, estimated to cost approximately $350,000,000, will be the longest large-diameter gas pipe-line ever built anywhere.Let me try to paint a broad picture of this great national project, using only a few basic 'round' figures.First, it involves exploration for and development of the natural gas fields in Alberta and other provinces -the cost of which will run into hundreds of millions of dollars.Then comes the gathering, stripping, and cleaning of the gas before it can be delivered to Trans-Canada. This will cost close to $100 million.Next we have the Trans-Canada Pipe Lines project for transmission of the gas to Eastern markets -estimated to cost $350,000,000 during the first three to four years and making natural gas economically available to one-half the population of Canada."

Jan 1, 1955

By A. Alfantazi, L. Choudhary

Gold leaching in thiosulfate solution has attracted widespread research interest through the last two decades primarily due to its perceived environmental benefits in comparison to the conventional gold cyanidation technique. However, the data on the corrosion and/or corrosion-induced failures of plant infrastructure materials in the solutions relevant to thiosulfate gold leaching are very limited. Accordingly, this study aims to characterize the electrochemical corrosion behavior of stainless steel 316L in the thiosulfate gold leaching solutions. Electrochemical corrosion response was investigated using potentiodynamic polarization and electrochemical impedance spectroscopy. The morphology of corroded specimens was analyzed using scanning electron microscopy.

Jan 1, 2014

By Balmer Neilly

Early in my term of office it was announced that my Presidential Address would make particular reference to the subject of Mine Taxation in Canada. With this purpose in view there was drafted a Balance Sheet and Earnings' Statement of a Gold Mining Company. This in turn was submitted to the Dominion Income Tax Authorities in Ottawa and to the Minister of. Mines of each of the several Provinces of Canada. The response to the invitation was not as complete as we had hoped it would be, but the figures that were obtained will be presented during the present meeting, and they constitute, I hope, a sufficient basis for extended study and additional enquiry during the year to come ( 1) . In the form letter that accompanied our request to have the submitted earnings assessed, I made the following assertion: "In this work we have three objects in mind. 1.--We will get direct comparison between the different Provinces in Canada. 2.-We will in this way educate our members concerning taxation as it affects the mining industry. 3.-We will publish the details as to how the assessment is calculated by each body, so that a Mine Manager in the most remote district will have a ready reference to guide him in his annual return to the taxing bodies. As things stand, there is no intention of making this a basis for a critical attack on the present rates assessed. It is intended as an authoritative summary of actual conditions as they presently exist".

Jan 1, 1934

By Terry Gerritsen, Sylvain Picard, Bruce MacKay

Virtually all new technologies require a control system. Any intense process has many process variables that react quickly making manual control difficult. Control system design has a significant impact on the success of a plant especially during ramp-up. New technology projects are particularly sensitive to control system design as the process response is unknown. This paper discusses the important factors encountered in the design of a control system for a new technology. Examples are given of successful new technology plant start-ups where tight coordination of the process control system implementation, process design and selection major equipment led to rapid ramp-ups.

Jan 1, 2011

By A. R. Farkoosh

Al-Si based alloys have been recently used by automotive industry for highly stressed engine applications. Due to severe working conditions of the engine parts, existing alloys hardly endure high pressures at high temperatures. This necessitates alloy modifications to enhance the elevated temperature performance. In this study, the effects of trace nickel additions on the microstructural and mechanical properties of A356+0.5Cu alloy have been investigated at different aging conditions. Electron probe microanalysis (EPMA), scanning electron microscopy (SEM) and X-ray diffraction (XRD) are used to study the microstructural changes. Aging curves have been obtained by hardness measurement. It was seen that the presence of additional nickel introduced many complex intermetallic phases within the microstructure which led to improved high temperature mechanical and aging response.

Jan 1, 2011

By V. P. Mehrotra, D. W. Fuerstenau, A. -Z. M. Abouzeid

The use of pulverized coal for electric power generation results in the production of vast amounts of fly ash. One potential use for waste fly ash is the production of pellets for lightweight aggregates. This paper is concerned with the role of the physical and chemical characteristics of two different fly ashes in governing their agglomeration or pelletization behavior and their strength characteristics. In batch balling experiments, fly ash pellet growth was found to be extremely sensitive to the amount of moisture added. One ash (Mohave) exhibits marked pozzolanic activity whereas the other (Jim Bridger) does not. The pozzolanic activity has a very pronounced effect on pellet growth kinetics, moisture requirements, and the effect of various additives on growth kinetics. Slow drying under ambient conditions produces strong pellets from Mohave ash whereas Jim Bridger ash pellets lacking in pozzolanic activity are weak. Rapid drying at high temperatures results in weak pellets because water necessary for hardening is driven out of the pellet. Steam curing enhances pellet strength. Locked-cycle pelletizing experiments exhibit expected oscillation in pellet production rates and attendant fluctuations in pellet green strength.

Jan 1, 2004

By M. J. Scoble, H. L. Francis, D. F. Salter, G. R. Baiden

Intelligent ore delineation refers to the ability reliably to characterize the geological setting of a mineralized body and its grade distribution. This necessitates using all available geological information in a timely and efficient manner, such that effective geological control is achieved. The importance of geological control is paramount to improving the efficiency and competitiveness of underground mines. As a result, the development of new geosensing tools designed to provide more reliable and timely information should be a priority. However, as the sensing tools advance then so, too, must the decision support system in order to allow the full benefits of these tools to be achieved. One potential system considered able to provide this architecture is ’true 3D-GIS’ (Geographical Information System). GIS promises to provide a seamless data flow and to connect information currently unavailable to the underground mine operations by bringing together previously disparate and spatial data sets in a visually effective and timely way. This paper considers the potential revolution GIS offers over the flow and use of data in mining by focusing on the integration of geosensing data and GIS to facilitate intelligent ore delineation.

Jan 1, 2000

By S. Setayeshgar

The identification of potential accidents on construction sites has been a major concern in the construction industry and it needs a proactive safety plan to reduce the risk of accidents. There are no efficient methods for checking if safety measures are taken properly on construction sites. Consequently, workers on site are not given enough awareness about dangerous areas. In addition, construction sites are dynamic and on-site situations are changing in terms of permanent and temporary structures and facilities. This information can be represented using Building Information Modeling (BIM). This paper proposes the integration of BIM and safety risk analysis by considering the risk levels associated with the work spaces of different construction tasks. Work spaces are generated in a BIM model according to the Work Breakdown Structure (WBS) of the project, reference objects in the BIM, and the schedule and resources of the task. Each work space is assigned to one or more tasks or functions, e.g., work spaces for specific tasks, shared spaces (paths), storage spaces, or spaces prohibited to workers. The assignment of work spaces is based on the workers, equipment and materials involved in the task. All the work spaces are associated with a specific duration according to the schedule of the project. Then risk evaluation of the construction site is applied in order to evaluate safety risks based on their severity and the degree of exposure of workers. For example, work spaces for storing hazard materials and for heavy construction equipment have higher risks than other work spaces. The results of the risk evaluation can be visualized in a 4D BIM model.

Aug 1, 2013

By A. L. Mackie

Arsenic is a highly toxic element and a known human carcinogen. It is often a contaminant in mine water discharges, particularly from gold mining and roasting operations, and has been found at concentrations as high as 4 g/L. Increasingly stringent controls on the concentration of arsenic allowed to be discharged into the environment cannot always be met by current treatment processes and thus enhanced technologies are required to achieve low treated effluent concentrations at reasonable costs. A novel two-step physicochemical treatment process was developed and tested at the bench-scale using synthetic mine water solutions (SMWs) in order to reduce arsenic concentrations in treated effluent to exceed current discharge regulations. The process includes chemical coagulation with ferric sulphate and ballasted flocculation for enhanced solid-liquid separation. The SMW contained 59 ± 2 mg/L arsenic with a slightly alkaline pH. The effect of arsenic speciation on the process was tested by using either arsenite, As(III), or arsenate, As(V), in the SMW solutions. Tests were performed at cold temperature (3 ± 1 °C) to ensure the process? efficacy year-round in northern climates. Arsenic in As(V) SMW solutions was removed to a final total concentration of 0.0054 ± 0.002 mg/L, almost half the current recommended allowable drinking water concentration of 0.010 mg/L. As(III) was removed to a concentration below the Metal Mining Effluent Regulations? (MMER) current limit of 0.50 mg/L, to 0.32 ± 0.06 mg/L, with double the coagulant dose used in Stage 1 for As(V) removal. Oxidant addition at a concentration of 5 mg KMnO4/L in Stage 2 resulted in final total arsenic concentrations of 0.017 ± 0.002 mg/L and pH adjustment with lime in Stage 2 resulted in 0.0415 ± 0.0007 mg As/L in treated As(III) SMW. Both of these modifications to the process reduced arsenic concentrations to below proposed new MMER limits (i.e., 0.10 mg/L). This two-stage treatment process was shown to reduce arsenic concentrations to well below current treatment guidelines while reducing or eliminating chemical oxidant demand.

Aug 1, 2013

By E. M. Stiles

Introduction The papers that follow deal with recently completed major improvements in practices at the Sullivan operations in Kimberley. The papers have been prepared by members of the Consolidated Engineering Staff and outline the construction programme which has been in progress for the past three years, entailing an expenditure of some millions of dollars. Four major operational changes have been brought about in the mine and concentrator. They are: (1) A change in backfill procedure for filling stopes below the 3900 level. (2) A 12,000-ton,per-day sink-float plant at the concentrator. (3) A new haulage system from the mine to the concentrator. (4) A completely new crushing plant and ore storage facilities located underground. A brief outline of the background and history leading up to this overall project will be given to show how each started as an independent betterment and how they were finally co-ordinated into one major programme. The first of these, namely, the necessity for backfilling stopes below the 3900 level, was the most pressing problem. All filling to date bad been done above the 3900 level, where mining was carried on in an irregular pattern of open stoping. Stopes below the 3900 level were first opened in 1940 and are being worked on a regular pattern of panel sub-level open diamond drill stopes. The two areas are separated by a sill pillar traversing the entire length of the vein at the 3900 level elevation.

Jan 1, 1950

By R. Bonifaz, R. Subiabre

The Chagres Smelter, part of the Anglo American plc group, situated 80 Km north of Santiago in Chile, completed a series of operational improvement in 2005 resulting in an optimum capacity in its operational units. At present the Chagres Smelter has developed an operational strategy which seeks to reduce bottle-necks in the production process. In this way we have managed to lower operational cost, decrease energy consumption and maximize the capacity of the Acid, Oxygen, and Smelting, Converting, Refining and Casting units. A constant review of international benchmarks together with continuous staff improvement and the latest smelter technology have combined to place Chagres among the finest smelting works in the world. In response to environmental challenges, we have studied various options for investment that will yield a suitably profitable business to benefit both Anglo American and Chile. The most relevant technical indicators are: energy consumption=6,3 GJ/ton fine copper (1st in the world), intensity of smelting rate in Flash Smelting unit of 6,900 ton of copper concentrate/m2 of furnace area (1st in the world) and to be one of the top five smelters in achieving the lowest direct cash cost .

Jan 1, 2007

By J. R. D. Gravel, D. A. Poland

"The induration of iron ore pellets has always utilized prefired pellets to protect the pallet cars from the environment of the induration furnace. This paper presents the process used to obtain superior upper sidewalls. These heat resistant castings are used on induration pallet cars, and their life improvements by as much as 400% is a significant step towards the reduction of the prefired (or hearth layer pellets.) The benefit to the industry in the removal of the hearth layer is improved overall productivity. IntroductionThe Iron Ore Company of Canada (IOC) operates with production facilities located in Labrador City, Newfoundland and Sept Iles, Quebec. It has recently been acquired by North Limited, an Australian based resource oriented company. Prior to its acquisition, IOC has examined several methods of operational cost reductions. One of these was an examination of indurrating pallets. Pallets are composed of numerous assemblies and sub-assemblies. The examination of the upper sidewalls began as an intent to increase the operational life of the component. The anticipated net effect was to be a reduction in the overall pallet maintenance cost. All of the components and assemblies have undergone a severe scrutiny. IOC has found that the success of the project has depended upon not only the technical competency of all parties involved, but also upon the ability to share risk, to be innovative, and to find a partner with whom the development can proceed without fear and yet with accountability. IOC has found in Cast Steel Products (CSP) such a partner in the field of pallet development. This paper will undertake to explore the progression into the arena of partnering between IOC and CSP. CSP and IOC met in the fall of 1994. The work of re-engineering the pallets began with an initial order for 36 pallets in March, 1995. The work on the upper sidewalls involved segregation of the effect of alloy development versus physical geometry development. The nature of partnering between the two companies allocated alloy development to IOC and physical geometry development to CSP, yet no advancements were made in either area without the close co-operation or the involvement of both partners."

Jan 1, 1999

By Jonathan Matthews

Efficient and effective management of mine tailings is essential for continued successful development of Alberta?s vast oil sands resources. Syncrude Canada Ltd. continues to research novel tailings management techniques in an effort to improve production efficiency and environmental sustainability. During the summer months of 2001, Syncrude Canada Ltd., in collaboration with members of the Canadian Oil Sands Network for Research and Development (CONRAD), conducted field-scale trials of thickened tailings technology at Syncrude?s Aurora mine, north of Fort McMurray, Alberta. This paper provides an overview of the test program including discussion of objectives, test configuration, and program observations. 0Data collected during the field trial indicate that substantial swings in feed slurry composition challenge effective thickener operation. When coarse mineral solids dominated slurry composition, thickener rake torque rose to unmanageable levels. It was determined that the end-of-pipe depositional characteristics of thickened oil sands slurry were generally consistent with present understanding of oil sands tailings slurries. After shear, thickener underflow product exhibited very shallow beach angles and a limited capacity to keep coarser particles in suspension indicating that stacking of ?paste-like? thickener underflow product from a conventional thickener is not practical in an oil sands setting unless process adjustments can be made to increase the underflow density and/or preserve the initial high yield stress of the underflow during transport and deposition. These technical challenges notwithstanding, Thickened Tailings technology offers considerable promise for recovery of warm water from oil sands process tailings.

May 1, 2003

By T. R. Kostecki, K. V. Jessu

"Roof bolts are subjected to axial stresses, shear stresses, or both. Axial and shear stresses were compared between roof bolts machined with two and three slots. Shear stresses perpendicular to and at an angle to the shear planes were evaluated by analyzing a three-slot instrumented roof bolt, performing laboratory tests on two- and three-slot roof bolts, and conducting in-situ test analyses. Threeslot bolts appear to provide a complete bending strain profile, requiring no prior knowledge of the estimated shear-plane orientation. Minimum displacements occur in roof bolts installed perpendicular to rather than at an angle to the shear planes.RÉSUMÉ Les boulons d’ancrage dans le toit d’une mine sont sujets à des contraintes axiales, des contraintes de cisaillement ou les deux. On a comparé les contraintes axiales et de cisaillement de boulons d’ancrage usinés avec deux ou trois fentes. Les contraintes de cisaillement perpendiculaires et à angle aux plans de cisaillement ont été évaluées en analysant un boulon d’ancrage de toit à trois fentes, en effectuant des essais en laboratoire sur des boulons d’ancrage de toit à deux et à trois fentes et en effectuant des analyses de tests in situ. Les boulons à trois fentes semblent fournir un profil complet de résistance aux contraintes de flexion, sans avoir besoin de connaître l’orientation estimée du plan de cisaillement. Des déplacements minimums ont lieu dans les boulons d’ancrage de toit installés perpendiculairement, plutôt qu’à un angle, aux plans de cisaillement."

Jan 1, 2016