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By Gaston Gendreau

CETTE PRÉSENTATION traitera des différentes phases des opérations de la mine du Mont-Wright depuis ses débuts jusqu'à présent. A une brève description de la géologie du gisement, suivra un exposé des méthodes d'exploitation de la mine et du genre d'équipement utilize.

Jan 1, 1977

By M. D. Vance, G. R. Corbett, S. D. Butt

Surface wave imaging is a relatively new seismic technique that generates subsurface depth images without having to drill boreholes into the ground, and is rapidly becoming a standard tool in non-destructive geotechnical characterization. This paper presents a case study of the application of these surface wave techniques to image shallow abandoned mine workings at the Montague Gold Mines district near Dartmouth, Nova Scotia. This district has numerous steeply dipping narrow vein workings from historical mining activity, and has actively subsiding and collapsing crown pillars. Due to the rugged conditions at the site and the relative narrowness of the openings (often less than 1 m), a surface seismic system was developed that had improved portability and lateral resolution over other available seismic imaging systems. Seismic surveys were conducted over two sites where independent evidence indicated the presence of shallow mine workings. At one site, a comparative gravity survey was also conducted. The seismic data was processed to generate velocity vs depth images. Overall, the velocity images show vertical zones of zero velocity in the same lateral positions where historical mapping, current subsidence and gravity surveys indicate the presence of steeply dipping workings. Further, the velocity sections are consistent with the thickness of the till cover at each site and the possible weakening of crown pillars at one of the sites.

Jan 1, 2005

By K Morrison

Different individuals have calculated the boundary stresses around elliptical openings in an infinite elastic medium for various conditions of loading. With caution, such calculations are useful in indicating stress trends in mining. This paper illustrates an application to caving operations and suggests that abnormal field stress would have an adverse effect. Introduction GELDART and Udd (1), applying elastic theory, confirmed, and set out graphically, the stress distributions on the surface of elliptical openings with axis ratios varying from 1.0 (a circle) to infinity (a crack). The loading conditions varied from uniaxial to hydrostatic, and inclinations for the opening, with respect to the stress axis, varied from 0° to 90°. As most mine openings can be generalized into this elliptical conception, the usefulness of the presentation lies in the fact that given reasonable estimates for the stress ratio, the axis ratio, and its inclination, then the trend in stress concentrations as an opening develops can be readily approximated.

Jan 1, 1964

By M. Grenon

OBJECTIVE ?To link slope stability and financial assessment algorithms into a commercially available mine design software packages to provide integrated global pit optimization.

May 1, 2013

By Shinji Muraishi, Shinji Kumai, Yasutaka Kedo, Takashi Kambe

"Magnetic pulse forming (MPF) is one of the extreme high-speed forming processes. A metal sheet which is accelerated by electromagnetic force is collided onto a mold and fine and sharp details of the product can be obtained. The deformation mechanism of the MPFed metal cannot be understood only by the microstructure observation of the deformed metal. The deformation behavior of the metal should be investigated also by considering the local microstructure change with strain, strain rate and temperature change during deformation. Numerical analysis is an effective method to achieve this requirement. In this study, pure Al and Cu sheets were deformed by MPF. Impact velocity of the metal sheet was calculated by using ANSYS Emag-Mechanical. Based on the obtained impact velocity, the deformation behavior of the metal sheet was reproduced, and local strain, strain rate, and temperature were analyzed by using ANSYS AUTODYN. The relationship between the local microstructure change of Al and Cu sheets and the deformation parameters was examined.INTRODUCTIONMagnetic pulse forming (MPF) is one of the high-speed forming processes using electromagnetic force. Fine and sharp details of the product can be obtained, and springback after deformation is extremely reduced in comparison to the conventional forming processes(Psyk, Risch, Kinsey, Tekkaya, & Kleiner, 2011). Figure 1 shows a schematic diagram of MPF. A metal sheet is placed over the coil in the discharge circuit. The discharge current runs through the coil, and magnetic fieldis producedaround the coil. An eddy current is inducedin the metal sheet. Interaction between magnetic field and eddy current creates electromagnetic force. The metal sheet accelerated by electromagnetic forcecollides ontothe mold. Forming is completed in a few tens of micro-seconds.MPF is suitable for metals with a high electrical conductivity like Al and Cu.The MPFed metal may have characteristic microstructure because of high strain rate deformation."

Jan 1, 2018

By M. Hozayen, Q. Ni, E. S. Radwan, P. Nawrocki, A. Jebbouri

"A major geomechanical study was conducted for one of the UAE onshore oil fields with the purpose of studying reservoir rock properties and stress distribution, based on which a 3D coupled reservoir geomechanical model was built. This model was later used for wellbore stability analysis and for analyzing the effect of fractures on future reservoir production performance, including fracture deformation and permeability evolution occurring due to reservoir depletion and resulting changes in local stress field. The subject of this study was a complex fractured Upper Cretaceous carbonate reservoir characterized by high degree of heterogeneity, both vertically and laterally. Wellbore instability related drilling problems were encountered while drilling the wells in this field. The problems were mainly in drilling the horizontal wells, including breakouts and mud losses. Experimental results of laboratory tests used in this study are summarized in Part I of this paper whereas wellbore stability analysis and formulation of a3D geomechanical model that was built for that purpose is summarized herein.A 3D geomechanical reservoir model was developed, which included natural fractures. The mechanical properties of the reservoir rock, such as Young’s modulus, Poisson’s ratio, UCS, friction angle and tensile strength were populated based on the correlations established in Part I of this paper and the developed model was then used to simulate the 3D mechanical-property distribution and the evolution of the in situ stresses in the field due to depletion from 1983 to present-day. Based on the full field model, mud weight cubes were developed to predict the safe mud weight windows in different drilling directions. In addition, well stability prediction for two planned wells was performed using a 3D near-borehole model. Firstly, the computed stress state and mechanical properties simulated in the full field model were extracted along the well trajectory of an existing horizontal well which was drilled recently and then, a3D near-borehole model was constructed along the well trajectory. The wellbore stability analysis along the well trajectory, including stress state, strain distribution and displacements, was performed to identify the instability events along the well trajectory. It has been seen that the presence of natural fractures is closely related to the recorded borehole instability incidents. The computed plastic strains which indicate the wellbore failure were consistent with the recorded wellbore instability events in the FMI image logs, what provide further verification of the developed model. Then, this 3D near-borehole model was applied to two planned horizontal wells and the wellbore stability analysis for the two wells was carried out.The results showed that drilling vertically in the reservoir is safer than drilling horizontally. However, the drilling mud weight window in the vertical direction is narrow, being as narrow as 18.7 pcf or 0.299 sg locally. Drilling horizontally is less stable towards the maximum far field stress direction than towards the minimum far field stress direction. The mud weight cubes were used to identify the optimal well placement and well trajectory. For planned well trajectories, this technology can also be used to determine the optimal mud weight."

Jan 1, 2015

By S. Steinlechner, G. Schneeberger, J. Antrekowitsch

Due to always getting stricter environmental legislations as well as increasing land filling fees the efforts for treating residues from metallurgy are continuously increasing. In case of filter dusts from metallurgical industry, the high zinc bearing electric arc furnace (EAF) dusts or also dusts from secondary copper industry are important sources for the recovery of secondary zinc oxide. Because of low capacities for secondary zinc concentrates (like Waelz oxide) in primary zinc metallurgy, the upgrade of such concentrates to a quality that meets the requirements of high quality (technical) zinc oxide becomes more and more important. This would open the opportunity to break into new markets and use it for example directly in electrolytic galvanizing. Therefore this paper will summarize possibilities for an elimination of halogens from secondary zinc oxides. Furthermore selective volatilization trials, with a synthetic mixture according to the analysis of Waelz oxide, were carried out to remove impurities to achieve an upgraded product quality.

Jan 1, 2011

By Lorna Ortiz-Soto

A series of titiania- and silica-supported Au, Pt and Pt-Au catalysts prepared through different synthetic routes have been investigated in terms of their structural properties, adsorption of CO, and catalytic activity for the selective catalytic reduction of NO by propylene and the oxidation of and CO. Catalysts prepared by incipient wetness impregnation from individual Pt and Au precursors, exhibited characteristics very similar to those of monometallic Pt catalysts. This behavior is consistent with a model in which the two metals remain segregated due to their miscibility gap, and only Pt participates in the adsorption of CO and the reactions under consideration. In contrast, catalysts prepared from a Pt2Au4(C=CtBu)8 organo-bimetallic cluster precursor exhibited different behavior both in terms of CO adsorption and their catalytic activity for the three reactions examined. The combination of the kinetic, spectroscopic and structural characterization data suggests that in this case Pt and Au remain intimately mixed in the form of Pt-Au bimetallic particles, and that the presence of Au modifies the behavior of Pt.

Oct 1, 2003

By W. Kempson

"Mining Companies have producing assets in increasingly diverse portions of the world. It is not uncommon that the owner, the design team, the mine contractors and the operators are all based in different countries. While these assets are always subject to the regulatory requirement of those countries there have not been international standards available to review and evaluate these assets. This becomes particularly important when considering safety critical items such as tailings dams, vertical shaft systems and autonomous vehicles to highlight a few. The work currently being completed in ISO ensures these standards will be available and will be generated by and subscribed to on an international basis, thus removing the potential for patriotic partisanship and ensuring safe and predictable systems are installed. This paper will discuss the benefits of the international standards, the structure of the teams and working groups who are generating these standards as well as the process by which the standards are generated. This will allow insight into the creation of the standard and will aim to demonstrate the “neutral” and technically strong manner in which the generation of these standards is achieved. In addition, the paper will discuss the standards which have been produced in the last five years as well as the current standards which are in place. The finale will discuss upcoming work and the timelines in which it is anticipated these will be completed. INTRODUCTION Mining Companies have producing assets in increasingly diverse portions of the world. While these assets are always subject to the regulatory requirement of those countries, there have not been international standards available to review and evaluate these assets. This becomes particularly important when considering safety critical areas such as vertical shaft systems, tailings dams and autonomous vehicles to highlight a couple. The work currently being completed in the International Organization for Standardization (ISO) ensure these standards will be available and will be generated by and subscribed to on an international basis, thus removing the potential for patriotic partisanship and ensuring safe and predictable systems are installed. The ISO/TC 82 – Mining was founded in 1955. This was an active committee until it was thought that the standards at the time were adequate and the Technical Committee was put on “Care and Maintenance”. In 2012 countries lobbied ISO to pull this committee from dormancy and restart it, this happened in in the same year."

Jan 1, 2019

By John D. Lupton

This paper will discuss the benefits and advantages of using 3D survey data in stope analysis. Obtaining detailed 3D survey data of underground mine progress and production is a challenge. It is almost impossible to ?see? around corners, underneath overhangs, or deep into dark, dusty, humid underground voids. Thus, valuable ore can remain permanently encased in backfill. Without the benefit of 3D survey data, underground mines have the difficult task of meeting grade quotas without the benefit of knowing exactly what has been mined. Lack of this data usually results in unfavorable month end Reconciliation factors, where grades must be adjusted to match grades assessed by the Mill.

Apr 1, 2005

By Theophile Yameogo

The rock mechanics literature has documented the challenges, failures and successes of tunneling through weak rocks. Cases usually deal with low RMR rock masses or high stresses in a fractured zone. With the combination of 5MPa water pressure, 14 RMR ground with clay infillings and ground freeze walls, the case of the 510-8225N development drift at McArthur River is certainly much more challenging, especially when high grade uranium production is at stake. The article explains the excavation and the ground control techniques that were used to overcome the challenges of development at the Unconformity in the Athabasca Basin.

Aug 1, 2010

By Charlie Graham, Helen Shang, Ashley Scott, Andrew Hall

"Approaches to Energy Recovery• Upgrading for electricity generation - steam turbines• Direct extraction- process improvement or space heating- support medium for animal or plant growth– fish or microalgae• Heat pumps- space heating/coolingWater Energy Grades• High (150+ °C) - electricity Generation• Medium (26 to 121 °C) - direct extraction• Low (5 to 18 °Celsius)- use of heat pump is required• Temperatures between zones will depend on circumstances for best use."

Jan 1, 2012

By T. Haubold, K. Ortner, T. Jung, D. Roth-Fagaraseanu, C. Mattern

Application of integrally bladed disks (blisks) is of increasing interest in compressors of aero engines. Blisks are preferred due to their potential for size and weight reduction, for increased performance and for reduced manufacturing costs compared to conventionally bladed disks. Erosion of the blisk aerofoils in service reduces engine performance, and can result in short shop visit cycles. This significantly increases the life cycle cost of these components, particular when considering that eroded aerofoils can't be exchanged easily for blisks during refurbishment. Shop visit cycle times can be extended and maintenance costs can be reduced through the application of an effective protective coating. The ongoing development of an erosion resistant coating and deposition process suitable for coating complex blisk geometries is described here. The coating is a multilayered W /TiB2 system exhibiting superior erosion resistance compared to known single- and other multilayer concepts. A modified sputter process is used to enable coating even of blisk geometries with shadowed surface to competitive recurring cost.

Jan 1, 2006

By M. H. Ali

Codelco, a multi-process primary copper producer, is undertaking a full life cycle inventory (LCI) of all its commercial products based on copper and molybdenum. During this work, many questions have surfaced regarding the contribution of process unit design to specific aspects of a product's LCI and, more importantly, how such designs could be improved using a life cycle perspective. Management strategy efforts were undertaken to improve the LCI footprint, however it was found that the corrective actions were almost impossible to apply at the operation level in plant, given the ongoing timing pressures of extractive mining, and costs saving priorities. Additionally, it was found that most of the important comparative differences between operations had structural reasons. In this circumstance, the LCI practitioner group from 1M2, and the environmental managers from Codelco, decided to shift its efforts to place the critical LC1 aspects to the design process of future developments. Hatch Associates has developed unique tools in their Sustainable Plant Design (SPD) package that compliment and enhance LCA methods; these effectively drive sustainability into the heart of the design process. By using LCA and SPD in a project design phase, you cannot only address potential hotspots, but also decide on materials, location and size of certain facilities to optimize for energy efficiency. Moreover, you can avoid the shifting of environmental burdens upstream or downstream within the plant and finally it is extremely useful in identifying opportunities for greenhouse gas reduction.

Jan 1, 2007

By Z. S. Abisheva

The Zhezkazgan copper sulfide ore deposit in Kazakhstan contains both rhenium and the rare osmium isotope "osmium-187" (187Os) in the high isotopic purity of 99.4 ± 0.2%. This isotope is believed to have originated as a result of the disintegration of one of the rhenium isotopes, according to the reaction: 187Re75 ?> 1870576 + B- + v~ (where B is a 13-particle, v~ is a 3-disintegration antineutrino). The distribution of osmium and rhenium in metallurgical byproducts produced during the recovery of copper from these ores has been studied and process flowsheets for the processing of rhenium and osmium-containing byproducts have been developed.

Jan 1, 2007

By V. M. Robb, F. Walraven, L. J. Robb

"The old Albert Silver Mine is a polymetallic deposit comprising concentrations of CuPb- Zn-Ag-U-F within a set of sub-parallel quartz-hematite veins which occur within the fine-grained apical phase of the 2050 Ma old A-type Bushveld granites. Mineralization occurs as an early pyritechalcopyrite- arsenopyrite-galena-sphalerite-(argentiferous) tetrahedrite paragenesis followed by a later, more oxidized assemblage comprising chlorite-hematite-fluorite-pitchblende. Accumulation of metals appears to have taken place at the interface between a coarse-grained porphyritic granite and an overlying fine-grained phase: veins occur in the latter and represent leakage of magmatic fluids from the differentiated, water-saturated, subjacent granite.Mineralization processes in the Bushveld granites are believed to be related to long-lived circulation of dominantly magmatic fluids stimulated by the high heat productive capacity of the host rocks. Endo- and exogranitic tin-tungsten and base metal mineralization formed during an evolving hydrothermal system that lasted for several hundred million years, forming innumerable small- to mediumscale polymetallic deposits. At the Albert Silver Mine, unroofmg of the cover sequences at circa 1600 Ma to 1700 Ma resulted in the incursion of lower-temperature, high-f02 meteoric fluids which remobilized the earlier sulfides and introduced the paragenetically late U-F mineralization."

Jan 1, 1994

Overview of Presentation Why Enter Agreements with First Nations Making it Win-Win ?The Principles The Process Making the Process Work Resource Agmts Defined Resource Agreements are legally binding agreements between a resource company and the First Nation(s) whose Aboriginal or Treaty rights may be impacted by the activities of the proposed project

May 1, 2009

By H. Soltanzadeh

This paper summarizes semi-analytical and closed-form solutions that can be used to assess the poroelastic stress changes induced within a porous formation (reservoir) during a pore pressure change. Further, solutions are presented for the stress discontinuities at the interfaces between reservoirs and the rocks that surround them. When used in combination with rock failure criteria, these solutions enable relatively simple analyses of the potential for induced fracturing or fault reactivation within a reservoir or the rock immediately adjacent to it. The latter, in particular, is useful for assessing if the hydraulic integrity of the surrounding rock (i.e., the bounding seal) will be affected by a pore pressure change. The use of the approach presented in this paper is illustrated with an analysis of a pinnacle reef with dimensions and properties representative of reefs in the Zama oil field, northwestern Alberta, Canada. Scenarios of pore pressure decrease (during historical production operations) and pore pressure increase (during several years of acid gas injection operations) are analyzed, for three different idealizations of reservoir properties and geometry (two plane strain and one axisymmetric). These results suggest that that the potential for induced fracturing is not significant at any point within the reservoir or the surrounding rock for both the production and injection scenarios that were simulated. Similarly, fault reactivation was not predicted for the reservoir or any of the points that were analyzed in the surrounding rock. However, fault orientations having the greatest potential for reactivating during historical production operations were identified; thus, illustrating a means of using geomechanical models to focus geological characterization efforts on the features that are most critical to acid gas containment.

May 1, 2009

By Leroy C. Stewart

Owing mainly to the use of ethylene dibromide in the production of tetraethyl lead for gasoline treatment, there has been a tremendous increase during the past decade in the demand for bromine. In the United States, production, derived mainly as a by-product from the treatment of brines from salt wells, rose steadily from about two million pounds in 1924 to nine million pounds in 1931. In 1936, production amounted to between 20 and 21 million pounds. Much of the increase during the past four or five years has been due to the operation of the Ethyl-Dow Chemical Company's plant, which extracts bromine directly from sea water. The process employed by the Ethyl-Dow Company is somewhat similar to that in use on salt-well brines at their plant at Midland, Michigan, but whereas these brines contain around 1,300 parts per million bromine, sea water contains only 65 to 70 p.p.m.-about as much as the waste effluent in the brine process. By intensive research, however, a process was developed whereby a very considerable percentage of the bromine content of sea water could be recovered, and at a satisfactory operating cost. In its essentials, the process consists in liberating the bromine from the sea water by treat-ment with chlorine, blowing the bromine out of the water by a current of air, and finally absorbing it in a solution of soda-ash.

Jan 1, 1938

By M. Oliazadeh

The bioleaching of fine low grade copper sulfide ore is described. A sample of ground (> 1 mm) copper ore from Sarcheshmeh, Iran, was subjected to a series of agglomeration procedures and subsequently leached. The best agglomerate was obtained by using lime and sulfuric acid as binders. A column bioleaching test of agglomerated ore was then run for 105 days along with a non-inoculated control column having thymol as bactericide. The results show that about 77.5% of copper was extracted in the bioleaching, whereas the control column achieved only 57% copper leaching.

Jan 1, 2007