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By P. M. Solozhenkin, O. I. Ibragimova, I. P. Solozhenkin

Molecular models of complexes of poorly studied bismuth, gold, and arsenic mineral clusters and reagents were created for use in collector activity forecasting using Chem Bio 3D and ChemOffice2005, with optimization by MM2. The density functional theory approach was used to determine HOMO, LUMO, SOMO, and total energies, atomic charges, and s, p, d- populations for various compounds. The structure-based virtual screening (SBVS) and docking technique was proposed to reduce the vast number of compounds to a more manageable number for selection of potential flotation candidates. The prognosis of collector activity evaluation (PCAE) strategy was proposed as a consistent approach to estimate the interaction between a collector and a mineral cluster as the difference between the total energy and sum of cluster energy and collector energy to search the analogue of butyl xanthate. The negative relationship between PCAE and flotability was shown. The combinations of dialkylamino sulfhydryl collectors can be considered as prospective reagents for gold-bearing sulfide ore flotation. These results were confirmed by experimental data in ore flotation. The increase in recovery of gold and bismuth with the aid of a combination of reagents has been established and additional cyanidation of tailings has been avoided.

Jan 1, 2016

By Ainul Akhtar, Steve Cockcroft, Daan Maijer, Carl Reilly, Lu Yao, Jun Ou

A coupled thermal-fluid flow-multicomponent model has been developed to aid in understanding the melting/dissolution behavior of solid Al-rich Material (TiAl) in a liquid titanium pool produced by an electron beam. The model is capable of accounting for the significant phenomena present affecting heat, mass and momentum transport including thermal and compositional buoyancy and Marangoni forces, Darcy attenuation, evaporation, melting and solidification, and the associated release or absorption of latent heat. The modeling results have indicated the compositional fluid flow driving forces (compositional buoyancy and Marangoni forces) contribute significantly to the melting/dissolution process. The model is waiting for validation against empirical data.

Jan 1, 2014

By W. M. Williams

"Although manganese is a metal virtually unknown to the layman, it is hardly necessary to point out to the engineer the importance of manganese in modern metallurgy, an importance intimately linked with iron (and steel), the basic materials of engineering construction for hundreds of years and certain to remain so for long into the future. World steel production will approach and perhaps reach 1 billion tons/year in the 1980s; with a manganese content between 0.5% and 1 % in ordinary steels, and more in specialty steels, manganese use worldwide will soon approach 15 million tons annually. Manganese was discovered and isolated in Sweden in 1774 by Karl Wilhelm Scheele (who also discovered molybdenum), but the element was only of scientific interest for several decades. By the early part of the nineteenth century, however, manganese oxide had become commercially available and was in use for colouring glass and for the production of chlorine. Commercial application in metallurgy appears to have been limited to the manufacture of crucible (or ""cast"") steel, a highquality product made by carburizing wrought iron, and melting it in small batches to make ingots which could be rolled and used for special applications, e.g. for the manufacture of fine tools or for ""steeling"" the cutting edges of implements such as wrought iron axes and chisels.* However, it was not until Bessemer's epoch-making invention of cheap steel in 1856, and the dramatic expansion of the steel industry thereafter, that manganese assumed the importance that it holds in modern steelmaking."

Jan 1, 1999

By E. Latorre, T. S. Golosinski

ABSTRACT; his paper proposes new methodology to define the pit limits that yield the maximum net present value (NPV) for a deposit, under a given economic scenario and for a given discount rate. The method uses an algorithm that combines dynamic programming and heuristics. It was tested for evaluating deposits with different sizes and various grade distributions. For the discount rate of zero, the results confirm that the economic pit limits are the same as that defined using Lerchs Grossman method. However, when discount rates higher than zero are used, the pit limits differ, yielding a higher NPV.

Jan 1, 2011

By T. Nomura, N. Saitoh, K. Tamaoki, Y. Konishi

We have developed new recycling technologies, based upon an eco-friendly biotechnology, in order to extract precious and rare metals sourced from end-of-life products and electronics. We have been focusing on the metal ion-reducing bacteria, Shewanella algae and Shewanella oneidensis, that are able to reduce and deposit gold ions (Au(III)) or PGMs ions (Pd(II), Pt(IV) and Rh(III)) into metal nanoparticles at room temperature within 120 min. When processing the aqua regia leachate of printed circuit boards, Shewanella bacteria were able to rapidly and selectively collect gold ions under acidic conditions in the presence of heavy metal ions, proposing a new bio-recovery system for gold. This biotechnological procedure also has the potential to allow the recovery of PGMs from the leachate of automotive catalysts. Shewanella bacteria were also able to successfully perform the complete reduction and deposition of the PGM ions. The ability to collect the PGM ions suggests that this represents a new process for the biorecovery of PGMs from used automotive catalysts. Our proposed biological method enables the rapid and highly efficient recovery of precious and rare metals via separation and concentration utilizing microbial reactions at room temperature.

Jan 1, 2014

By G. Cailletaud, I. Guillot, D. Larouche, R. Martinez, D. Massinon

The precipitation of Al2Cu particles in a 319 T7 aluminum alloy has been modeled. A theoretical approach enables the concomitant computation of nucleation, growth and coarsening, based on an implicit scheme using the finite differences. The equation of continuity is discretized in time and space in order to obtain a matricial form. The inversion of a tridiagonal matrix allows us to determine the evolution of the size distribution of Al2Cu particles at t + dt. The fluxes of solute in-between the boundaries, as well as the ones at the boundaries, are computed in order to respect the conservation of the mass of the system. The main results of the model are compared to TEM measurements. Simulations provide quantitative features on the impact of the cooling rate on the size distribution of Al2Cu particles in good agreement with the TEM measurements. This metallurgical model is integrated into FEA software in order to perform mechanical computations. This kind of multiscale approach allows new perspectives to be investigated in the process of designing cylinder heads. It enables a more precise prediction of the microstructure, its evolution as a function of continuous cooling rates and its impact on the integrity of the structure.

Jan 1, 2015

By Mike McKevitt

We are trying to promote a concept and a change in management?s approach to the iterative process of grade control. This is important as grade control must routinely try and achieve the long term objectives set by the mine plan ??BackgroundBackground ??Factors contributing to variation from planFactors plan ??Basis of OptimisationBasis Optimisation ??Ore Block Optimisation processOre process ??Operating mine examplesOperating examples ??Chain of Mining. ??Intention is to highlight the need for repeatable and consistent materialand material-type classification to remain consistent with the Life of Mine Plan ??We can drill another hole or reWe re-optimise a plan, but once excavated, the final decision has been made ??The grade control decision is the last decision made in the resource exploitation sequence.

May 1, 2009

By M. Phylli Bray

"Mining has the reputation of being a very ""macho"" industry. Recently, wider educational opportunities for women in nontraditional occupations and changes in mine technology have combined to make mining a viable career choice for women also. To benefit from this new resource, the mining industry faces the challenge of developing a different work environment from the one now burdened with sexism. Management supported initiatives are needed to facilitate such a transformation. The same rethinking of gender attitudes might also be extended to mining women in their traditional role as ""wife of"". The assumption that the male worker's wife is an unpaid adjunct is being questioned. It is suggested that women's separate concerns both as helpmate and as part of the mining workforce should be considered when planning for mining into the 21st century.IntroductionI must confess that, during the preparation of this paper, there have been many moments when I questioned my temerity. After all, I am not male, I am not an engineer, and I have never had a position in mine management. But as the wife of a mining engineer and a long-time resident of Northern Ontario mining towns, I do have an interest in the mining industry. This interest has had little to do with the technical and management aspects of the industry. Instead my research has been concerned with the impact the mining industry has on the people involved, particularly women, whether directly as employees or indirectly as wives. As I look toward the 21st century, I believe that the whole question of gender relations in the mining industry is one of the critical management issues smouldering below the surface."

Jan 1, 1995

By Robert E. McIvor

"Use of the Bond Work Index to size industrial grinding equipment was widely known. Bond also described its application for measuring grinding circuit efficiency. Bond Work Index efficiency also has been used extensively by industry, but until now without concise standard methods, or a formal guideline, for doing so. The Bond Efficiency Sub-Committee of the Industrial Comminution Efficiency work group of GMSG has produced such a guideline, which is appended hereto. It covers the methods and provides examples of how to calculate the Bond Work Index Efficiency of most industrial grinding circuits. Bond Work Index testing equipment and methods are also provided.Comminution is responsible for a major portion of mineral processing plant energy consumption and operating costs. Bond Work Index efficiency provides valuable means, first, for benchmarking one’s plant performance against others in the broad industry, and hence defining the extent of the opportunity for improvement. Secondly, improvements in circuit efficiency with implemented changes can be quantified and monitored as part of continuous improvement efforts. These two important business activities are thus facilitated, and, in the absence of any other accepted method, otherwise would be lacking without the existence and application of this standard for comparison. While often loosely applied in the past by plant metallurgical staffs, the increased precision offered by this guideline provides much clearer definition of both the conceptual and statistical meaning of these measurements. Even a small improvement can be enormously financially important, but only if differentiated by measurement. This guideline was thus intended to provide industry improved means to differentiate comminution circuit efficiencies. Carbon footprint reduction is coincidental, but nevertheless can be substantial.The next steps are: (1) to establish standard reference testing materials and one or more laboratories to serve as bases for reference testing; (2) to establish the accuracy of relative circuit Work Index Efficiency determinations; and (3), to develop and provide a public data base of industrial comminution circuit Bond Work Index Efficiencies."

Jan 1, 2016

By S. Leong

This paper reports on research examining disclosures from mining companies regarding their water usage in the Macquarie and Lachlan catchment areas, both parts of the Murray-Darling Basin in New South Wales, Australia. The objective of the research was to assess whether this disclosure is sufficient to allow communities to determine whether mining companies are complying with mining conditions of consent and abiding by the requirements of their water licencing agreements. These requirements are then compared to the water reporting requirements of the Global Reporting Initiative (GRI) and the Water Accounting Framework for the Minerals Industry (WAFMI). Communities are concerned about whether the mining industry?s use of water will have impacts on their livelihoods and lifestyle and thus require information concerning the quantity of water that will be extracted, how much water will be left for other stakeholders and whether the mining will affect water quality. This is an archival study. It has involved examining relevant publically available information released by mining companies and government regulators and determining if this is sufficient to meet the needs of the local communities. Additionally, it has involved looking at information indirectly provided by mining companies, via the use of intermediaries. Further, information availability concerning basic water accounting and regulatory breeches and whether such information is available at the mine site level has been considered. It is found that while NSW legislation places very little reporting requirements on mining companies, the development consent conditions for new projects and extensions to existing projects are quite significant and should be sufficient to meet the needs of local catchment residents though such information is not always easily accessible for the layperson.

Aug 1, 2013

Partnership with MiHR ? AHRC and MIHR jointly developed Mastering Aboriginal Inclusion for Mining ? Customization specific to mining Mining is unique? ? History of Aboriginal peoples and the land ? Unique community needs ? Effects of Impact Benefit Agreements ? Remoteness of mines ? 1200 Aboriginal communities located w/in 200km of active mines or exploration ? Long term effects of the land

May 1, 2009

By Juan Asalgado

The JORC and NI43-101 codes impose that mineralized material has a reasonable prospect of economical extraction to be classified as Mineral Resource. For deposits close to surface and amenable to open pit mining, it is easy to show reasonable prospect of economic extraction running a Lerch-Grossman optimization. The Lerch-Grossman pit provides a transparent and repeatable way of separating the Mineral Resource (within the pit) from the remainder of the mineral inventory (outside the pit). Deposits amenable to underground mining are more challenging because of the variety of the underground methods. AMEC developed a stand-alone software package that outlines the material which has reasonable prospect of economic extraction for open stoping, block caving, sublevel caving and room and pillar. The software takes a block model file in ASCII and exports a 3D surface outlining the part of the mineralization that has a reasonable prospect of economic extraction, and which the Qualified Person can smooth out manually if required.

Oct 1, 2009

By T. Gerritsen, T. Plikas, K. Ochoa, M. Loveless, R. MacRosty, J. Reichart, R. Pula

Sidewall accretion in a smelting furnace plays an important role in furnace integrity as it provides protection to the sidewall cooling elements and thereby extends the furnace campaign life. The extreme thermal and mechanical stresses in the furnace and changes in the slag chemistry can cause the sidewall accretion to melt or break away decreasing the lining protecting the cooling elements. Thin accretion is highly undesirable as it increases the risk of exposing the cooling elements to the molten bath and in the worst case may lead to a failure. Therefore, monitoring the sidewall accretion on an operating furnace is extremely important to manage furnace integrity and to support safe furnace operation. Operators often generate estimates for sidewall accretion and refractory thickness using either copper cooler temperatures or heat load into the cooling water circuits. Multivariate statistical models, on the other hand, have the capability to consider all the process measurements simultaneously to provide a more reliable estimate. This paper describes the application of multivariate statistical models for sidewall integrity monitoring on a Flash Converting Furnace (FCF) and also discusses the online implementation of these models as the Sidewall Accretion Monitoring System. INTRODUCTION Rio Tinto’s Kennecott Utah Copper (KUC) smelter located near Salt Lake city, Utah operates a Flash Smelting Furnace (FSF) and a Flash Converting Furnace (FCF) to produce high-grade matte and blister copper respectively. Since the commissioning of smelter in 1995, several improvements were made to these furnaces to increase their efficiency and operational safety. At present, Kennecott smelter is known to be among the lowest-emission and highest energy recovery copper smelters in the world. Since the smelter start-up, Kennecott has invested in several advanced furnace monitoring practices to evaluate the integrity of the furnaces and improve their campaign life. An example is their temperature monitoring system installed for the smelting and converting furnaces, which continuously monitors the furnace sidewall temperatures and notifies the operators during temperature excursions. During an investigation on the converting furnace, it was revealed that there were frequent temperature excursions in the settler sidewall area towards the reaction shaft end of the furnace that caused significant furnace downtime. The reason for the sidewall temperature excursions was not clearly known.

Jan 1, 2019

Situation Brands & Employment Value Propositions of mining sector firms are perceived negatively Competitive labour market is generally not aware of the diversity of mining careers Jobs requiring unique skills & experiences are no filled Traditional means of generating awareness to attract candidates is not aligned with how youth (for example) uses technology throughout the recruitment process Gobal economic downturn

May 1, 2009

By E. L. Martheleur

A general expression for the electric power generated or consumed in a direct-current circuit is obtained by multiplying the reading of a suitable voltmeter connected across the terminals by the reading of an ammeter connected in the circuit. by the reading of an ammeter connected in the circuit. When alternating currents are considered, the product of the volts and amperes as obtained for direct currents does not generally represent the true energy involved; it is greater than this true energy and should be multiplied by a certain factor which may have any value between zero and unity, according to the conditions of the circuit. This factor is called the power-factor of the system, and expresses the ratio of the true energy over the apparent energy. For a three-phase system the expression of the apparent energy is [\/ 3 x E x I; ] while the expression of the true energy, that is, energy suitable for mechanical work, is [v? 3 x E x I x cos A.] The total current of a circuit corresponds to the reading of an ammeter connected in the circuit; it is the resultant of two currents. The first of these is in phase with the voltage, and is that portion which really produces mechanical work; the second is always in quadrature with the voltage, that is it may lead or lag the voltage by 90° according to the condition of the circuit. This second current does not produce any sensible work, and for this reason is sometimes called wattless current or reactive current.

Jan 1, 1924

By L. Bichler

Lightweight magnesium alloys are gaining in popularity for applications in the automotive and aerospace industries, Their use, however, remains limited due to their relatively low strength and creep properties. Lost Foam Casting (LFC) is a new casting process and the strength of foam cast magnesium alloys has not been investigated in great detail thus far, In this research, magnesium alloy AZ91 E and three new alloys were cast by the LFC process to study the effect of varying aluminum and manganese content on the alloy's tensile properties, The study reveals, that the tensile strength of the magnesium alloy is closely related to the relative amount of aluminum in the system. Formation of ß-Mg17Al12 phase was seen to significantly affect the yield strength and ductility of the alloy, Furthermore, formation of manganese intermetallic compounds was seen to effectively increase yield strength of the base alloy, Individual alloy morphologies were analyzed via optical and SEM techniques.

Jan 1, 2004

By Alan E. Cameron

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

Jan 1, 1945

By M. H. Rana

"A survey of our knowledge in the field of rock mechanics is presented from the viewpoint of applications in the mining industry. Aspects of rock mechanics of special interest to the industry are enlarged upon, with emphasis on the avoidance of over-generalization. The relationship between fundamental and practical rock mechanics is discussed, and the need for cooperation between the university and industry to further our knowledge of -useful rock mechanics is emphasized. An attempt has been made to establish the scope of rock mechanics, as applied to problems in the mining industry. This is brought about by projecting rock mechanics as a tool to be intelligently used rather than magic, capable of producing ""miracles."" Continued education is important for individuals engaged in the application 0f rock mechanics in the mining industry. The scope of this education is discussed from a viewpoint of better communication between industry and the education and/or re-search establishments engaged in this work.Finally, the dangers of over-emphasis on rock mechanics are mentioned, but a justification of the in-vestment in rock mechanics programs in mines is also presented."

Jan 1, 1966

By P. H. J. Mercier, M. Couillard

Aberration-corrected scanning transmission electron microscopy (STEM) allows for the nano-scale exploration of materials at unprecedented resolution and sensitivity. In this paper, we combine this approach with electron energy-loss spectroscopy (EELS) and energy dispersive X-ray spectroscopy (EDX) to analyze the carbon distribution in residual solids found in solvent-diluted bitumen product extracted from Alberta oil sands. Major components of these contaminant solids are ultrafine clays. Biwettable clays have been associated with the formation of solid-stabilized water-in-oil emulsion, which are known to increase the content of both water and mineral solids in the final bitumen product. We demonstrate that the residual solids present in bitumen product contain carbon intermixed with mineral particles of various size and shape. By probing the carbon content at the nanometer scale with the high chemical sensitivity of EELS, we provide direct evidence of carbon intermixing with clay platelets. This clay-organic association at the nanometer-scale will contribute to the biwettable, hydrophobic character of the platelets, and will therefore play a crucial role in the bitumen extraction process

Jan 1, 2014

By R. Tremblay, M. Burrows

"In the summer of 1990, pilot scale testing of a Jameson cell was carried out at Falcon bridge Limited, Kidd Creek Division. The Jameson cell is self aspirating and has fewer mechanical parts, thus it has a lower operating cost compared to conventional cells. This lower operating cost combined with positive pilot scale results, justified the evaluation of two full scale cells in the plant. The plant test had two mandates:1. Gain a thorough understanding of the cells operation and design constraints.2. Develop a flow sheet to replace three divisions of copper cleaner flotation.This paper provides an overview on the installation, commissioning and evaluation of the two Jameson cells acquired. The current status of the test program is also discussed.IntroductionThe Falcon bridge Limited-Kidd Creek Division concentrator is located in Timmins, Ontario. The concentrator, commissioned in 1966 and expanded in 1978, consists of four parallel grinding and flotation divisions utilising small cell (60 ft3) technology. With increasing pressure to maintain low operating unit costs a series of studies were undertaken to assess the impact of new technologies in the flotation circuits. The goals of the project were to improve productivity through increased metallurgical performance and/or reduced operating costs.One of the technologies investigated was the Jameson cell designed by Dr. Graeme Jameson of the University of Newcastle and marketed by MIM Holdings Limited, Australia. This style of column technology was chosen based on its potential for reduced capital and operating cost versus large conventional cells.The success of pilot testwork in 1990 led to the installation of two production sized Jameson cells beginning in October 1991. The units were to be used to confirm pilot results and determine equipment requirements for flotation modernisation. This paper will discuss the results and experiences Kidd Creek has had with the Jameson cell from pilot scale through installation and commissioning of the plant units."

Jan 1, 1993