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By Mafalda Arias

Most mining and mineral exploration companies? operate in remote locations, in Canada or internationally. Not knowing the cultural imprint of your team and the places where your company is active, may lead to problems. To set the foundation for a better world, it?s important to built trust and relationships inside your global team, within communities and together with stakeholders. Building the ?invisible asset? and developing intercultural awareness is an important part of leadership programs for geologists and engineers on your team, and should be a key component of your Corporate Social Responsibility initiatives. Why is culture important for mining and mineral corporations in their CSR initiatives? Because culture is the foundation of your organizational identity. Understanding the impact of identity, for an organization and for each individual, will provide a description of the experiences and values that affect every work placed interaction, with your clients, with colleagues, with suppliers, with the community of the host country. Each one of us sees and evaluates the world through our perceptions. Through these perceptions we give meaning; how we view and understand our reality which sets the tone for how relationships are built. This is what I call building the ?invisible asset?. Identity, experiences, values and beliefs are invisible commodities, locating them can be as difficult as finding a mine. But if they are not located, the commodity does not have value. Just like in the work we do in our industry. For example when you are working in an underground gold mine and the vein is lost, you keep on working and trying to find the vein; time passes, money is being used and no results. You decide to bring an expert on this type of deposits who gave you directions that allowed you to find the vein. To be a responsible citizen of the world and to set the foundation for a better world, it is imperative to go deep, as deep as your next drilling program, because only there and then, can you develop the cultural sensitivity and the ability to become an agent of change for responsible, sustainable and profitable businesses.

Oct 1, 2010

By F. Bourgeois, J. -S. Kroll-Rabotin

ABSTRACT: Falcon concentrators are enhanced gravity separators designed for concentrating fine particles. The Falcon UF model is unique in that it is dedicated to beneficiation of ultrafines, one key feature being that it does not make use of any fluidization water. We investigated the physics of particle transport inside Falcon concentrators, and concluded that separation efficiency is governed by differential settling velocity. We derived and published a predictive model of the partition function under dilute conditions. We intend to extend the initial model to concentrated ultrafine suspensions for application to industrial scenarios by adding hindered settling to account for solid concentration effects.

Jan 1, 2011

By J. Stiksma, K. Buban, J. Oftsie, R. Kalanchey, S. Sadykov, E. McConaghy

The Kazakhmys zinc refinery in Balkhash, Kazakhstan, which employs the Dynatec Zinc Pressure Leach Process, officially launched autoclave operations on December 27, 2003. The Kazakhmys plant is the world's first greenfields zinc refinery based on Dynatec's two-stage pressure leach technology. Production of zinc was realized on February 9, 2004, when the first cathode was stripped. Currently the plant start-up is ongoing, with progression to two-stage zinc pressure leach operation and ramp-up to full design capacity continuing through 2004.

Jan 1, 2004

By G. V. Fernandez

Sociedad Minera Cerro Verde S.A.A leaches secondary copper sulfides. In recent years, the mine has introduced innovations that have improved the management of mineral crushing, agglomeration, curing, and leaching. The crushing plant, for example, uses the concepts of degree of balance and percentage of time in an operationally balanced state which, displayed in real time, facilitate more intensive and uniform utilization of the crushers. High agglomerate quality is ensured with the correct dose of moisture, which is adjusted to the changing characteristics of the mineral through the use of electrical conductivity measurements. The amount of acid used for curing the agglomerate is also adjusted by using quality control information. Finally, the stockpile irrigation regime is managed using the criteria established by the "Lixiviant Request Rate", which optimizes the addition of leaching solution, creating such benefits as faster recovery, and reduced acid and energy consumption.

Jan 1, 2007

By Jos. Kalbhenn

MR. G. G. BOWSER: Mr. Kalbhenn's paper is an excellent one and is a concise description of a very interesting piece of work. It is well known that a great deal of preliminary study was given to this job before the final plans were made. It is due to this thorough preparation .chat the work progressed so satisfactorily, smoothly, and safely. The ideas carried out in the construction of the hardwood pack, timbered compartment, inclined raise, loading chute, and steel-boomed room, all contributed to a successful conclusion of the work. The extra care in being certain that the compartment shafts were well timbered was especially necessary on account of the difficult blasting conditions. In other words, the foundations .of this job were well and truly laid. The blasting in this work was very difficult due to the nature of the Strata. Working under an ever precarious roof condition and completing .this job with only two lost-time accidents is a record of which to be proud. The shaft men engaged on this work are also due for praise. I regret I did not visit this work while it was in progress. It was not in lack of interest. This, however, more or less proves that the blasting end .of this job went along with practically no trouble. I have seen the nature of the rock, as I made several visits to the tunnels while they were being put through from the Phalen to the Harbour seam. According to figures in Mr. Kalbhenn's paper, the explosives consumption works out to 1.61 pounds per cubic yard of rock in the solid, or 0.8 pounds per ton. The explosives consumption in the tunnels ran from 2.86 to 3.46 pounds per cubic yard or an average of 1.58 pounds per ton of rock. Of course, the rock in the shaft was blasted in the most economical way possible, as far as powder costs are concerned, as the face advanced at close -wright angles to the strata and gravity was acting with the explosive. The tunnels were driven nearly 'end on' the strata and bottom holes had to be lifted, and I believe there was some re-drilling of ribs left in the floor. I would like to congratulate Mr. Kalbhenn on his very fine paper.

Jan 1, 1944

The AG/SAG circuit discharge P80 is now increasingly referred to as the ?Transfer Size? or T80 for short. From the literature it is apparent that in circuit design some approaches to the sizing of AG/SAG mills as well as the ball mills that they feed use this parameter. This paper reviews whether the use of the T80 is appropriate in this context. In the course of the review examples of AG/SAG discharge size distributions measured from range of operating circuits are used to illustrate the arguments made.

Jan 1, 2012

By Etienne S. Bieler

Mr. Chairman, Ladies and Gentlemen, I come to you tonight distinctly as a physicist, not as a geologist or a mining man. My experience in applied geophysics has been short, and I do not doubt that many of you have a much larger acquaintance: with the subject than I have. A little over a year ago, the firm of Alderson, MacKay & Armstrong decided to investigate the possibility of developing a new method of electrical prospecting suitable to our northern Quebec and northern Ontario conditions, and asked me to take up the work. A preliminary survey of existing literature convinced me that the field of induction methods was most promising. I wish to give you some account of the work carried on last summer in the Rouyn district in this connection with the very able assistance of Mr. H. G. I. Watson. Geophysical methods of prospecting can be divided generally into four classes: magnetic, electrical, gravitational, and seismic. Each class depends on the existence of a definite property in which the valuable mineral to be discovered differs materially from the surrounding rocks. In the four classes, the property will be, respectively, magnetic permeability, electrical conductivity, density, and elasticity. By far the largest differences occur in the case of electrical conductivity, where it is not rare to find ratios of the order of several millions, or even billions, between ores, sulphide ores especially, and the surrounding rock. Hence the sensitiveness and delicacy of electrical methods. Of these four classes, only two, the electrical and the magnetic methods, have been put to extensive practical use in the discovery of metallic ores. The other two classes are important mainly in connection with oil detection.

Jan 1, 1928

By K. Baris

Methane (CH4) present in coal seams, generally known as Coalbed Methane (CBM), Coal Mine Methane (CMM) or Coal Seam Gas (CSG), is a major energy source, as it is the primary constituent of natural gas. At the same time, released methane is a potent greenhouse gas (GHG) and a major safety hazard in underground mining operations. Therefore, a considerable effort has been undertaken to develop coal bed methane extraction and utilization technologies that can achieve both environmental and safety benefits. Countries with significant coal reserves and gassy seams, i.e., USA, Australia, Canada, China, India, Poland and Germany have developed mature methodologies and practices to extract, before and during mining, and utilize significant amounts of methane from coal seams. Nevertheless, on a global scale, methane recovery remains untested and many technical and economic challenges require urgent attention. The research presented in this paper, sponsored by the United States Environmental Protection Agency (EPA), is focused on the Zonguldak Basin, the only hard coal region in Turkey. The basin is known to contain very gassy coal seams and consists of three major regions: Armutcuk, Zonguldak and Amasra. Among the three, the Amasra coalfield is considered as the most favorable for CBM recovery, as it comprises of deeper coal seams and where a private company, Hema Enerji A.S. (Hema) is already developing coalbed methane production facilities. This study aims at developing a reservoir model to predict the potential CBM recovery from the CBM-2 well, the only producing CBM well drilled by HEMA Enerji A.S in the Amasra coalfield. History matching was utilized to model the 15-day production data and uncertainty analysis was performed to estimate the optimum values for the reservoir parameters. The produced model yielded an average production rate of 143 m3/day for 10 years. The total amount of CH4 to be produced during this period was 0.53 million m3. Furthermore, the total amount of GHG to be avoided was estimated at 6585 tCO2e.

Aug 1, 2013

By E. W. Mountjoy

THE Exshaw formation is a thin but very persistent black shale unit generally well exposed along the easterly scarp faces of the fault blocks comprising tl1e front ranges of the Rocky mountains. It is over lain by the Mississippian Banff shales and silty shales and underlain by the massive Palliser Limestone formation of late Devonian age. The Exshaw continues eastward under the plains of Alberta and on into Saskatchewan, with little change until it reaches the surface of the Palaeozoic-Mesozoic unconformity. During the summer of 1953, the writer was working- with a field party under Dr. J. L. Usher in the front ranges of the Alberta Rocky mountains. This party, sent out by the Mobiloil Company, conducted a geological survey of Devonian rocks between the towns of Banff and Jasper. The writer helped to describe and map these Devonian rocks and obtained first-hand information concerning the Exshaw shale and its relationship to the underlying and overlying sediments. Additional information was obtained from reference material and from a number of geologists whom the writer has consulted. Grateful acknowledgment is offered to them, to the Mobiloil Company for releasing field information, and to F. W. Beales and W. P. Hancock who helped edit the original paper for publication. Information from areas north and smith of that studied and from bore holes on the prairies is referred to. Localities mentioned may be found in Figure 1.

Jan 1, 1956

By S. K. Kawatra, S. J. Ripke, T. C. Eisele

It was determined by the authors that the water that remains in the filter cake after filtration in iron ore concentrators can contain several hundred times greater concentrations of calcium ions and other cations, due to surface chemical effects carrying the ions along with the water. Filter cake from two plants was analyzed. The water retained in samples of magnetite concentrate filter cake in Plant 1 contained 5088 ppm calcium and 5995 ppm magnesium, while the Plant 2 filter cake contained 231 ppm calcium and 119 ppm magnesium. These levels were dramatically elevated compared to the water that was removed from the concentrate by filtration for recycle to the plants (9 ppm calcium/15 ppm magnesium for Plant 1, and 11.9 ppm calcium/9.3 ppm magnesium in Plant 2). In addition to possible effects on agglomeration performance, the presence of these cations also affected the efficiency of filtration. In order to reduce the effects of these cations on filtration in Plant 2, carbon dioxide was injected into the slurry before it entered the filter press. This was found to increase filtration rates by up to 23.7%. Comparison of the results from the two plants shows that the concentrations of cations present in the filter cake will vary greatly from plant to plant, with correspondingly large variations in their effects on plant operations.

Jan 1, 2004

By M. L. Jeremic

The design of the long-hole sublevel mining method was originally based on the traditional assumption that the principal load was due to the weight of the overlying rock, and that the horizontal stresses are equal to one-third of the vertical stress. However, as mining progressed, the virgin lateral stress was found to be equal to or greater than the vertical stress. The virgin stress in the rock mass is not uniform throughout the folded orebody and adjacent strata. From detailed investigations, three basic patterns of virgin stress in ore panels have been inferred: uniform, bent and twisted. Stresses induced by stoping are up to three times greater than original stresses in the rock mass; they cause heavy ground conditions and make extraction of ore difficult. In the last ten years, the original mining system has been modified several times in order to destress the ground and improve the extraction of ore.

Jan 1, 1978

By M. G. Rylatt, G. M. Popplewell

"Production from Canada's first diamond mine is planned for the last quarter of 1998. The climatic conditions and the variation in kimberlite types to be treated have lead to the development of a compact and flexible processing plant.High kimberlite moisture contents and winter temperatures below -40°C have dictated a process flowsheet with limited in-circuit storage to reduce materials handling difficulties. The latest developments in High Pressure Grinding Roll technology will be used to liberate the valuable diamond, reduce diamond breakage, and increase fines production to reduce the amount of material for down stream processing in the Heavy Medium Separation section.A varying heavy mineral concentrate yield has lead to the development of a final Recovery section that will incorporate Attrition Milling and Wet High Intensity Magnetic Separation for concentrate reduction. The latest developments in diamond X-ray sorting will be used to produce a final diamond concentrate for mechanical sizing, weighing and packing.Fine tailings thickening will utilise Deep Bed Compression type thickeners. This relatively new technology can produce;i) high underflow densities at low flocculant dosage rates, andii) clear overflowswith a smaller thickening area than conventional high-rate thickeners."

Jan 1, 1998

By Masami Nakamoto

Controlled thermolysis of gold(I) thiolate complex, [C14H29(CH3)3N][Au(SC12H25)2], at 180 °C for 5 h under an N2 atmosphere produces novel gold nanoparticles passivated by alkyl groups derived from the precursor complex, the TEM photograph of which shows spherical particles with average diameter 26 nm. Since Brust et al. reported the two-phase reduction of AuCl4 - by NaBH4 to afford monodispersed gold nanoparticles passivated by alkanethiolate ligands (1), plenty of preparative investigations on gold nanoparticles (2,3) and its surface modification (3,4) have appeared, because of their potential applications in microelectronics (5). However, those preparative methods generally involve the reduction of AuCl4 - by reducing agent NaBH4 in the presence of suitable organic stabilizers such as alkanethiol (1-4), phosphane (5), quarternary ammonium salts (6), surfactants (7) or polymers (8). On the other hand, O?Brien et al. recently reported the preparation of organically capped gold nanoparticles at 190 °C, where tri-n-octylphosphine oxide and/or n-octadecylamine are used both as a reaction medium and as a passivating ligand (6), but this procedure also needs NaBH4 as reducing agent. Our strategy of novel preparative method of gold nanoparticles is the combination of reductive elimination of thiolate ligands and simultaneous attachment of organic moiety on the growing nuclei. Gold(I) thiolate complexes with ammonium cations were useful for our preparative method. We now report the controlled thermolysis of gold(I) thiolate complexes, [R(CH3)3N][Au(SC12H25)2] and [R(CH3)3N][Au(SC6H4-p-R?)2] (R= C14H29, C12H25; R?= C8H17, CH3), under an N2 atmosphere, where the powder of gold(I) thiolate complexes completely melts to afford the precursor liquid and then the liquid gradually decomposes. In spite of no use of reducing agent and solvent, reduction reaction is thermochemically induced to afford novel gold nanoparticles passivated by alkyl groups rather than by alkanethiolate ligands. Figure 1a shows a typical transmission electron microscopy (TEM) image of gold nanoparticles prepared by thermolysis of [C14H29(CH3)3N][Au(SC12H25)2] at 180 °C for 5 h, indicating a controlled growth of spherical gold nanoparticles. As shown in Fig. 1b, these spherical gold nanoparticles display the size distribution ranging from 5 to 50 nm. Although the particle size is larger than that of thiol-derivatized gold nanoparticles (less than 5 nm) prepared by NaBH4 reduction (1-3), the aggregation of gold nuclei is smoothly regulated and the growth of core gold is limited to be 26 nm in average diameter in spite of thermal procedure.

Oct 1, 2003

By Gaston Gendreau, Marcel Allard

"Sidbec-Normines Inc. est une société formée de trios partenaires soient: Sidbec, British Steel Corporation et la Compagnie Minière Quebec Cartier. L'objectif de l'opération minière est d'exploiter à ciel ouvert le gisement d'hématite spéculaire de Fire Lake et de produire au concentrateur de Lac-Jeannine, près de la ville de Gagnon, 6 million de tonnes de concentré pour alimenter l'usine de bouletage de Port Cartier.Le présent exposé a pour but de fa ire ressortier les caractéristiques d'une opération dont la mine est située à plus de 100 km du concentrateur, d'en faire ressortir les particularités touchant le transport du personnel et du minerai. En plus, on traitera de l'importance dans une telle situation d'une organisation efficace dans la gestion des services et de l'opération (atelier, concasseur, entrepôt, etc.).IntroductionSidbec-Normines Inc . a entrepris l'exploitation minière du gisement de Fire Lake, le 1er janvier 1977. Le but de l'entreprise est de produire annuellement six millions (6 000 000) de tonnes de concentré d'hématite (oxide de fer) titrant 66% Fe au concentrateur de Lac-Jeannine a partir d'un minerai d'une teneur moyenne de 33% Fe, extrait de la mine de Fire Lake. Ce concentré est ensuite achemine à Port-Cartier et alimente I'usine de bouletage.Les installations minières de Sidbec-Normines sont situées a trois endroits différents : la mine à Fire Lake, le concentrateur à Lac-Jeannine et l'usine de bouletage à Port-Cartier. La mine de Fire Lake se situe à 83 km de la ville de Gagnon et à 100 km du concentrateur de Lac-Jeannine. Une route provinciale relie la ville à la mine et au concentrateur. Le minerai est acheminé de la mine au concentrateur par chemin de fer et le concentré est transporté par train sur une distance de 309 km à l'usine de bouletage de Port-Cartier."

Jan 1, 1982

By James McManus

The original analogue instrumentation at Lornex Mining Corporation to optimize the throughput by controlling the power drawn by the semi-autogenous mills was found to be inadequate because of the frequent changes in ore type. Although the trunnion bearing pressure of the mill was a crucial control criterion, it was not utilized in the original control scheme. After several plant tests of different types of analogue controllers were unsuccessful in finding any control equipment suitable for this application, it was concluded that a digital process control computer was required. Computer control strategy to optimize the grinding rate by controlling the power and the bearing pressure of the semi-autogenous mill was developed and a Fox 2 /30 computer made by Foxboro was selected. After six months of experimentation, it was found that the throughput was increased substantially by computer control.

Jan 1, 1978

By E. Burdukova

Rheological measurements have found a wide array of applications in mineral processing research. Rheological properties of mineral suspensions are highly dependent on the mineral surface properties as described by DLVO theory, and the relationship between these properties and inter-particle interactions is well established. In this paper, rheological properties of mineral suspensions are used to study the differences in behaviour of isotropic talc and anisotropic zirconia minerals as a function of varying properties of the suspension medium, such as pH and polymer dosage, specifically carboxymethyl cellulose (CMC). It was found that the rheological tests when carried out in parallel with electrophoretic or point of zero charge measurements, clearly reveal differences between behaviour of the suspensions of isotropic and anisotropic minerals. These differences are further accentuated with the addition of carboxymethyl cellulose (CMC).

Jan 1, 2006

By R. W. Lawrence, O. Lopez

Many gold deposits in the world have not been developed clue to the presence of copper and other base metals which can cause metallurgical and environmental challenges clue to the formation of base metal cyanide complexes. SART technology (sulphidization-acidification-recycle-thickening) can resolve these issues by recovering copper as a high grade sulphide concentrate, recycling the associated cyanide back to the gold leach, and eliminating the downstream environmental liabilities. Project economics can be improved substantially, leading to a positive re-evaluation of new and existing gold-copper projects. Some aspects of the design and operation of two recently commissioned SART plants will be discussed.

Jan 1, 2011

By Jessica E. Heuchan

An industry survey has been conducted by the Queen's University Mining Engineering Department of 30 Canadian mining organizations to determine how effectively newly graduated mining engineers meet the needs of the industry. The principal objectives of the survey were to evaluate, and thus provide focus on change for, curricula being taught at Canadian mining engineering schools in service of the industry's needs; to provide feedback on current industry expectations; and to reinforce contacts with the industry as a means of providing future collaboration. A strong focus of the survey was placed upon industry's perception of the special attributes of engineering hires and applicability of student academic training to meet their industrial requirements. In providing this detailed summary of corporate responses, a clearer understanding of the mining industry's expectations of engineering training at Canadian colleges and universities has been gained.

May 1, 2003

By G. F. Colborne, A. Thunaes

"When the Canadian uranium milling plants went into operation during the early 1950's, they utilized flowsheets developed at the Radioactivity Division of the Federal Mines Branch in Ottawa. Since then, numerous process improvements have been made by the Mines Branch, by the operating companies themselves and by other research organizations. This paper will consider uranium milling technology from the standpoint of a new mine operator charged with the responsibility for the design of an economic flowsheet, and will indicate the range of process elements available to him and the testwork required to enable an intelligent decision to be made."

Jan 1, 1968

By S. P. Narayan

The hot deformation behavior of Pure Mg and Mg-0.29Ce alloy were studied by isothermal hot compression tests in the temperature range of 250 - 500°C and strain rate range of 10-3 - 102 s-1 in a computer-controlled 50kN servo hydraulic universal testing machine (UTM). The results show that the flow stress of Mg pure and Mg-0.29Ce alloy increases with strain rate and decreases after a peak value, indicating dynamic recovery and recrystallization. Process efficiency was increased by nearly 10 to 12% by addition of Ce in Mg. Mg pure exhibits instability zones between 250-275°C at 10 ? 102 s-1 and 400¬500°C at 101 ? 102 s-1 temperatures and strain rates respectively, rest is the safe deformation zone. Wherein, Mg-0.29 Ce exhibits two low efficiency zones from 250 ? 300°C at 10-2? 10° s-1, 400 ? 500°C at 101 ? 102s-1 and high efficiency zone at 450 ? 500°C at 10-3? 10-1s-1. 4D process maps were generated for the above said alloys which illustrate contours of power dissipation and instability in the 3D space of strain rate, temperature and strain.

Jan 1, 2011