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By D. Gagnon, B. Dubreuil, J. -M. Lalancette, D. Lemieux

"The pilot scale extraction of gold with a brine of sodium chloride and bromide at 30 ºC, in an atmosphere of halogens at atmospheric pressure, leads to gold chloride with 95% gold recovery. The use of dilute hypohalites (1 – 3%) instead of free halogens, which is strong enough to oxidize hypobromite into bromine, simplifies the recycling of halogens by electrolysis. With the recycling of water and brine, the regeneration of hypohalites and with a barren solid that is inert and stable. The Nichromet Extraction technology is a green process where the protection of the environment does not preclude profitability.INTRODUCTIONThe use of chlorides for the extraction of gold predates the discovery of chlorine by Scheele in 1774. In the Plattner chlorination process (Christy, 1888) sodium chloride and copper salt were used to promote gold recovery by amalgamation with variable results. The introduction of the cyanide technology in 1889 has led to a general use of this method for gold recovery. In the last decades, a return to chlorine in extractive processes has been noted (Ferron, Fleming, O’Kane and Dreisinger, 2002), mostly because of environmental pressure for non-cyanide technologies.This paper describes a closed circuit proprietary approach (Lalancette, 2009) developed and piloted by Nichromet Extraction Inc. for the extraction of precious metals with recycled mixed halogens; chlorine and bromine from hypohalites. DESCRIPTION OF THE PROCESSThe attack of gold by halogens can vary significantly. The rate of reaction is substantially higher with bromine (Br2) than with chlorine (Cl2), by a factor of more than five, although the oxidation potential of Cl2 is higher than Br2, as shown in Equation 1a and Equation 1b (Latimer, 1952)."

Jan 1, 2012

By J. Gao, H. O. Gekonde, S. V. Subramanian

"The functional role of inclusions at low cutting speeds is to promote ductile fracture in chip formation process, whereas the role of inclusions at high cutting speeds is to prevent tool crater wear by suppressing the tribological phenomenon of seizure at the tool-chip interface. Glassy oxide inclusions are engineered into the workpiece to form a viscous layer in-situ at the tool-chip interface at high cutting speeds. The viscous layer lubricates the tool-chip interface to prevent the seizure. In comparison with the large volume fraction of inclusions needed for promoting ductile fracture at low cutting speeds, the amount of inclusions required for lubricating the toolchip interface at high cutting speeds is very small and is in the range that is typical of clean steels. The chip fracture process at high cutting speeds is aided by strain rate hardening of the matrix, which facilitates chip disposal of relatively clean steel.Inclusion engineering for high speed machining involves the control of the rheology and composition of inclusions to meet target viscosity at the tool-chip interface. The application of thermodynamic models in controlled production of inclusions in steels designed for high speed machining is discussed."

Jan 1, 1998

By M. Feinendegen, Ph. Siebert, C. Clauser, K. Willbrand, M. Ziegler

"Three institutes of RWTH Aachen University collaborate on laboratory tests and numerical simulations of hydraulically driven fractures in igneous rocks. The project´s target is to enhance the understanding of hydraulic induced fractures for deep geothermal energy exploration. Based on the idea of creating new discrete fractures in hot dry rock (HDR) reservoirs, the current project stage deals with this process on a laboratory scale. Especially for this purpose, a new testing facility has been developed and laboratory tests are performed to verify a hydraulic fracture propagation code based on the extended finite element method (XFEM). The testing facility enables us to initiate and propagate fractures in large samples of dense rock under triaxial confining pressures and to monitor the fracture propagation by extensive measurements. This contribution gives a short introduction to the project‘s background and mainly focusses on the test facility, the experimental procedure and exemplary results.INTRODUCTIONThe most efficient technique to increase the permeability of subsurface rock is to initiate and open fractures by applying hydraulic pressure from a packed borehole-section and to inject fluid into these fractures to propagate them. Since its first use in petro industries to enhance the production of wells in natural gas and oil reservoirs, the interest in targeted creation of hydraulic fractures has increased exponentially. As the key technology to the extraction of unconventional gas from shale, hydraulic fracturing (HF) became a major topic in a heated public debate. Based on the fact that a fracture tends to propagate in a direction perpendicular to the minimal principal stress, hydraulic fracturing has become an established tool for estimating geological stress states in almost any depth. Enhanced geothermal systems (EGS) in HDR reservoirs use engineered fractures as a heat exchanging system for a cycling fluid driving a power plant."

Jan 1, 2015

By Robert J. Uffen

YOU will likely recall the accomplishments of the International Geophysical Year of 1957, with its polar expeditions, the discovery of the Van Allen radiation belts and the spectacular launchings of the first artificial earth satellites. Our know ledge of the exterior of the earth was greatly increased by this international, friendly, cooperative scientific investigation. The Inter-national Union of Geodesy and Geo-physics has now been joined by the new International Union of Geological Sciences in sponsoring a similar study of the earth's interior. The program will extend from January, 1962 until December. 1964, and is known as the International Upper Mantle Project. During the T.G.Y studies of the interior of the earth were relatively neglected, even though the same international •Cooperation in obtaining simultaneous world-wide observations, by similar instruments, is required to locate and study earth-quakes, for example, as it is to study the earth's upper atmosphere. The upper mantle is 1•emote from man, as it extends from a depth of about 10 km. to perhaps 1000 km., but its practical importance is great.

Jan 1, 1962

By A. Taylor

This paper considers mineral processing in zero gravity dry environments typical of asteroids or comets. The electro-dynamic separation technique using pneumatic flow systems is explored. Pneumatic delivery of solids is used because of extreme temperature changes and the possible scarcity of water. The present earth-based process and how it can be modified for these conditions is examined.

May 1, 2001

By J. H. Pee, Y. J. Kim, H. U. Lee, G. H. Kim

The general recycling process of tungsten scrap to produce tungsten raw materials (tungstic acid, ammonium paratungstate (APT) and WO3) have been carried out by the oxidation, milling, sodium-fusion, dissolution, and extraction processes. Many studies on the high temperature oxidation of tungsten scrap have investigated various aspects such as swelling kinetics, fracture resistance, and the effect of alloying composition. However, the accelerating factors on the scrap oxidation rate during oxidation were not considered here. In general, oxidized products were fused with sodium carbonate or sodium hydroxide to produce Na2WO4. Later in the process, solid Na2WO4 was dissolved in water. This process required considerable reaction time and was a costly process. Therefore, the aim of this study was to increase the solubility of solid oxidized products to produce Na2WO4 solution by hydrothermal reflux method. Na2WO4 solution was used to produce CaWO4 and H2WO4 by general chemical reactions with calcium chloride and hydrochloric acid. Ammonia solution was also added to the tungstic acid to produce APT. In this study, the effect of ammonia addition on the APT precipitation process was investigated in detail.

Jan 1, 2015

By C. J. Simensen, R. Østhus, H. J. Roven, K. G. Skorpen, H. Kalager

"This work encompasses co-extrusion of alloy Al4.5Mg at the core and rapidly solidified Al4.5Mg1Ag forming the surface layer. The goal is to produce a multi-material by co-extrusion having a relatively hard surface as compared to a softer core. At the same time, work hardening in both alloys is expected to be significant due to Mg in solid solution. Precipitation hardening at 160°C is studied by applying solution heat treatments at 560°C. The hardness increased from 80 to 130 VH in the surface material after 236 h. Surprisingly, the Al4.5Mg alloy also shows pronounced aging at this temperature, i.e. from 70 to 90 VH. The relatively high solution heat treatment temperature introduces grain growth in the core, but this is insignificant for the RS surface alloy. Blisters forms at the surface and cracks follows large portions of the interface. However, the tensile ductility is significant in all conditions due to very pronounced work hardening, i.e. for the as co-extruded, T6, under- and over-aged. The elongation at fracture ranges between 40–45% and the tensile strengths 240–275 MPa. The tensile properties increase linearly with the thickness of the RS alloy, i.e. following the rule of mixtures.INTRODUCTION Al-Mg alloys in 5xxx-series are classified as non-heat treatable wrought alloys (Polmear, StJohn, Nie, & Ma, 2017). The formation of the binary ß-Al8Mg5 does not give a substantial increase in the strength of the alloys (Mondolfo, 1976). When a third element like Ag, Cu or Zn are added, G.P.?zones are formed at low temperatures and intermediate, partial coherent phases are nucleated somewhat higher temperatures and finally a ternary, equilibrium phase is formed (Auld, 1968; Cousland & Tate, 1986; Mondolfo, 1976). Both the formation of G.P.?zones and intermediate phases increase the hardness and strength of the materials. An intermediate, hexagonal T´?phase is formed in Al-5 wt%Mg-1wt%Ag, and finally the equilibrium, cubic phase (Al,Ag)9Mg5 is nucleated (Cousland & Tate, 1986; Mondolfo, 1976)."

Jan 1, 2018

By D. Warkentin, T. Yeomans, R. Tavakoli, A. Nacu

"One of the most successful commercial methods of extracting gold from ores involves solubilizing gold as a gold cyanide complex, followed by adsorption of the complex onto activated carbon. The gold cyanide is subsequently eluted from the carbon to produce a concentrated gold solution suitable for electrowinning to recover the precious metals. Stripped carbon is treated in a kiln under a flowing steam atmosphere to reactivate its surface, allowing it to be reused. The aim of this study was to investigate the gold elution using a mixture of sodium hydroxide and isopropyl alcohol in both batch and continuous tests, with the eluates being electrowon on carbon foam cathodes. The effects of various factors, including alcohol content and sodium cyanide addition were studied. The addition of alcohol considerably improved gold elution kinetics, while the presence of sodium cyanide did not have a significant impact on either elution efficiency or kinetics. In all cases, efficient electrolysis was shown to be an important factor in maintaining effective carbon circuit operation.INTRODUCTION Gold dissolved as Au(CN)2- complex during cyanidation is recovered either by cementation with zinc powder, also known as the Merrill-Crowe process, or by adsorption into activated carbon through Carbon-in-Pulp (CIP) or Carbon-in-Leach (CIL) processes. Activated carbon loaded with gold is then eluted and gold is subsequently recovered by electrochemical methods. Conventional elution processes such as atmospheric and pressurized Zadra processes, involve stripping with a cyanide (0.1–0.2% NaCN) and sodium hydroxide solution (1–2% NaOH) at high temperature (90–140°C) over long elution times of 8 to 72 hours. In the Anglo American Research Laboratories (ARL) elution process, the acid-washed loaded carbon is pretreated with a strong sodium cyanide and sodium hydroxide solution (1–5% NaCN and 1–2% NaOH), followed by elution with water at 110–130°C. Solvent-assisted elution processes have also been reported, such methods use varying concentrations of alcohols (methanol, ethanol and isopropanol), ketones, or glycols to enhance atmospheric elutions at temperatures up to 95°C (Muir et al., 1985; Ubaldini et al., 2006; Espiell et al., 2008; Soleimani & Kaghazchi, 2008). The present work investigates the efficiency of isopropanol in the gold elution process, as well as the methodology of evaluating gold stripping processes in the lab setting"

Jan 1, 2017

By Derek H. C. Wilton

"The Cape Ray Fault Zone of southwestern Newfoundland contains two notable electrum/ base metal sulphide quartz vein lode occurrences hosted by two contrasting lithological units, viz. a graphite schist horizon and a granite. The two occurrences, although in proximity, are not in direct contact, but, based on geochronological, geochemical and isotopic evidence, they were apparently deposited from hydrothermal fluids generated as a vapour phase from the magmatic progenitor of the Windowglass Hill granite.This paper provides further evidence, from REE and background A u and Ag data, for the magmatic origin of the hydrothermal fluids. Wall rocks to the electrum-bearing quartz veins in both the schists and granite have experienced a LREE depletion probably due to leaching by Cl-bearing solutions. Gold and silver contents are typically low in all rock types but there is a slight elevation in gold concentrations in those units in contact with the Window glass Hill granite. The granite also has the relatively highest gold and silver contents of any unit in the region.IntroductionThis paper presents the evidence from rare earth element (REE) and gold/silver concentration data for the magmatic origin of hydrothermal fluids responsible for deposition of the Cape Ray electrum deposits of southwestern Newfoundland. The two deposits occur in the Cape Ray Fault Zone (Fig. I) within the Windsor Point Group and Window glass Hill granite. The larger occurrence is called the Main Shear Showing and consists of a deformed quartz vein horizon, which extends for - 6 km, within the late Devonian Windsor Point Group. This unit is an intermixed ignimbrite and mafic tuff sequence with associated schists (metasediments) and gabbros. The host rocks to the mineralized quartz veins are interleaved graphite, chlorite and sericite schists. Basal ignimbrites within the Windsor Point Group have been dated, by Rb/Sr isotopic methods, at 377 ±21 Ma (Wilton, 1983a). The basal ignimbrites also have enriched REE patterns, an elevated initial Sr ratio (0.709) and a peraluminous-siliceous nature which suggest they resulted from the partial melting of continental crust (Wilton, 1984)."

Jan 1, 1985

By E. Krause, V. G. Papangelakis, S. Garg, R. Mahadevan, E. Edwards

"Bioleaching uses iron and sulfur-oxidizing bacteria to extract base metals from sulfide minerals. As bioleaching involves breaking the iron-sulfur bonds by ferric attack, the biologically mediated rate of iron oxidation is recognized to play a key role in influencing the overall kinetics. In this study, we investigate the catalytic ability of an indigenous AMD culture for oxidizing Fe(II) in solution. This culture was subsequently adapted on pyrrhotite tailings (0.6% Ni) by gradually increasing the solids loading. Results from this study show that such an adaptation reduces the initial lag phase in the biotic oxidation of Fe(II), thereby allowing for a higher Ni extraction when compared to experiments with an un-adapted culture at a similar solids loading. The use of adapted cultures also helps to reduce the residence time for bioleaching of Ni from pyrrhotite tailings. INTRODUCTIONAs the world demand for pure base metals grows; the mining industry is increasingly faced with the burden of processing lower grade ores and mining waste streams in order to recover the occluded metal VALUES ((Watling, 2006). The extractive metallurgy of nickel from sulfide minerals focuses on using a combination of mineral processing, pyrometallurgical (smelting) and hydrometallurgical techniques to extract Ni from its ore bodies.Pyrrhotite (Fe1-xS) is commonly found in association with pentlandite and chalcopyrite in sulfidic Ni ores, such as those found in Sudbury, Ontario, and in Russia, e.g. Norilsk. The vast majority of this pyrrhotite needs to be removed using mineral processing techniques, in order to minimize the Fe and S contents of the concentrates that proceed on to smelting. If all pyrrhotite were left in the concentrate, much more slag and SO2 would be produced, and the smelter throughput would be limited. Beneficiation of Ni sulfide ores leads to the rejection of unwanted constituents as mining wastes, which may still contain extractable amounts of Ni (Edgar Peek et al., 2010)."

Jan 1, 2012

By Weiren Lin

The Mw 9.0 Tohoku-Oki, Japan earthquake occurred on 11 March 2011 produced a maximum coseismic slip of >50 m near the Japan Trench. To investigate why the plate boundary fault between the subducting Pacific Plate and overriding North American Plate which caused the earthquake had such unprecedented large coseismic displacement and slipped to the trench, Integrated Ocean Drilling Program Expedition 343 called Japan Trench Fast Drilling Project (JFAST) drilled three boreholes at Site C0019 through the earthquake fault about one year after the earthquake. Borehole C0019B dedicated to loggingwhile- drilling (LWD) penetrated ~850 meters below seafloor (mbsf) at a water depth of approximately 6890 m. The plate boundary fault is located at ~820 mbsf in the borehole and has been identified as the slip zone during the Tohoku-Oki earthquake. Borehole wall resistivity images obtained from LWD show that drilling induced borehole breakouts are available in a wide depth range above the fault but are not available below the fault. Breakouts are reliable indicators of the orientations of current maximum and minimum horizontal stresses and can also be used to constrain the horizontal maximum and minimum stress magnitudes. As results of breakout analyses, the maximum horizontal stress orientation highly varied in the upper part of the borehole, but has a clear preferred orientation in a northwest – southeast direction in the deeper part just above the fault. This orientation is approximately parallel to the direction of the Pacific Plate subduction. Stress magnitude constraints indicate that the post-earthquake stress states in the hanging wall are either in or close to the normal faulting stress regime. By inferring the pre-earthquake stress state and comparing with the constrained post-earthquake stress state, a significant coseismic stress change was interpreted. The stress change suggests an active slip of the frontal plate-interface consistent with coseismic fault weakening and a nearly total stress drop.

Jan 1, 2015

By Christoph Müller

Information exchange for mine process optimization is essential. Today, modern mining equipment uses the IREDES standard to exchange production plans and reports for easy management and storage. To gain further benefits from process optimization, a mine wide access to real-time information is needed as e.g.: The current status of a machine, operational details etc. Presently, real-time data exchange systems are developed by machine producers. Each machine producer uses its own way of gathering, managing, and storing production data. These proprietary mining processes increase the complexity of cross platform data exchange and management for mines which involves machines produced by different vendors. Casting and unifying the data requires much effort. For this purpose, ?IREDES On-line? currently is being introduced. The standard defines an open, web based method for the exchange of volatile real time machine information. Two different principles are used: Web Services for cross platform information exchange within the IT world and the optional OPC UA for use with automation and process control systems. With such a standard information from machines of different vendors may be managed by using one common platform without spending the effort for dedicated interface development. Additionally, information management and storage will become straight forward since all the data are of the same format. The IREDES On-line standard utilizes the latest IT technologies as well as the knowledge and experiences gained from the previous IREDES standard. The paper explains the benefits, the use, as well as the technical design of the standard and gives application examples from the practice.

Oct 1, 2009

By A. Djebara

Today, indoor air quality, especially in manufacturing industries, is of great interest due to the use of new processes and advanced materials such as those containing nanoparticles. Manufacturing processes generate aerosols (dry or wet) which can be detrimental to occupational health and safety and to the environment. Controlling metallic particle emissions during machining processes should limit their formation at the source, and thus minimize the risk of exposure; this at-source reduction requires the characterization of the particle emitted (size, nature, concentration, etc). The metrics normally used in characterizing fine and ultrafine particles include the mass concentration, the specific surface and the number concentration. Most of these metrics are affected by the size, the geometry and the density of the measured particles. Information about the form and the real size of the particles is thus very important. A procedure for collecting and characterizing fine and ultrafine metallic particles was developed and applied to the study of particles emission during the machining of aluminum alloys. It was found that metallic particles emitted during the machining of aluminum alloys are of various shapes and sizes, and this information must be taken into account when characterizing these particles.

Jan 1, 2011

By L. Henry Smith, David C. Arthur

"The Williams Mine is Canada’s largest gold producer, with annual production of 450 000ounces from 2 300 000 tonnes of ore. Highly mechanized and automated underground mining practices are employed in order to achieve and maintain high levels of productivity and minimize costs.The mine ventilation system is modified to include a new vent raise and variable pitchvane-axial fan. This addition allows several fan installations underground to be decommissioned. A substantial net savings in installed horse power is achieved.Heating costs associated with under-ground ventilation air are a significant portion of mine operating costs. Air heating costs are substantially reduced by recovering heat from upcast exhaust air, minewater and compressor cooling circuits. This waste heat is used to supplement propane fired air heating systems for underground ventilation air. An additional benefit is the availability of a heat sink for summer cooling of the compressors.System design, energy savings data and payback calculations are presented."

Jan 1, 1996

By T. Boyd, K. McTaggart, J. Qiu

"Hudbay Minerals’ Flin Flon process plant produces a copper concentrate and zinc concentrate from the three ores it processes: 777, Reed and Lalor. Unlike many Cu-Zn ores, the average Zn: Cu ratio in feed is around 2:1, whereas, in many Cu-Zn separation plants the Zn: Cu feed grade is substantially higher than 2:1. The lower Zn: Cu in plant feed is a challenge for limiting Zn recovery to the Cu concentrate. While total recoveries of Cu and Zn at Flin Flon are very good; selectivity is the key challenge and small changes in ore or plant, can result in quite variable Zn recovery to Cu concentrate, and accordingly, Zn recovery to Zn concentrate. Magnetic conditioning has been shown to be selective between the two paramagnetic minerals chalcopyrite and sphalerite. Statistical testing of magnetic conditioning was undertaken at Flin Flon with the objective of increasing Cu recovery to Cu concentrate without increasing the Zn recovery to Cu concentrate - in effect increasing Cu-Zn selectivity. This has been achieved elsewhere with magnetic conditioning with the probable mechanism being an increase in fine chalcopyrite recovery, and a reduction in entrained, ultrafine, non-activated sphalerite to Cu concentrate. The results did indeed show an increase in Cu recovery to Cu concentrate of 0.8% to high confidence, but the decrease in Zn recovery to Cu concentrate was not to high confidence. This is effectively an increase in Cu: Zn selectivity in the Cu circuit – higher Cu recovery with no change in Zn recovery. However, while there was an increase of 1% in Zn recovery to Zn concentrate with magnetic conditioning, the variability in this parameter meant that this increase, though larger in magnitude than the Cu result, was not to high confidence."

Jan 1, 2019

By Dale Scott

"The Aggregate Resources Inventory Program was initiated 10 produce reports which assess the aggregate resources of municipalities designated under the Pits and Quarries Control ACI, 1971.Each report consists of three copies accompanied by a text. The text describes the local mineral aggregate resources, extractive activity and characteristics of the ""Selected Deposits"". The first map shows the known sand and gravel resources and their quality. The second map indicates selected sand and gravel resources of primary, secondary and tertiary significance. The third map indicates both bedrock resources and bedrock areas suitable f or extraction. These maps and the text are prepared in a formal suited for use by planning personnel.Recently, the Aggregate Resources Inventory Program has undergone evolutionary changes. New sources of data are being utilized in the inventory reports; in particular, detailed field assessment by inspecting, sampling, drilling and backhoe pitting. Liaison and joint assessment with district and regional Mineral Resources staff of the Ministry of Natural Resources, and personnel of the Ministry of Transportation and Communications, are key components of the Program.Twenty-two reports were available to the public as of December 1980, with a further thirty-six awaiting publication. Our present production rate is 3.5 reports per month. The reports appear to be well accepted by the municipalities and have proven effective in conserving prime aggregate resource areas.IntroductionThe urbanization of Southern Ontario has resulted in a major increase in the production of industrial minerals, such as sand, gravel, clay, shale, gypsum and stone, for use as cru shed aggregate, building stone, lime and cement.Although mineral aggregate deposits are plentiful in Southern Ontario, they are fixed-location, non-renewable resources. The potential for extractive development is usually greatest in urban fringe areas where land-use competition is extreme. Comprehensive planning and resource management strategies are required to make the best use of available resources, especially in those areas experiencing rapid development. Such strategies must be based on a sound knowledge of the total mineral aggregate resource base at both local and regional levels."

Jan 1, 1982

By Dale Scott

"The Aggregate Resources Inventory Program was initiated 10 produce reports which assess the aggregate resources of municipalities designated under the Pits and Quarries Control ACI, 1971.Each report consists of three copies accompanied by a text. The text describes the local mineral aggregate resources, extractive activity and characteristics of the ""Selected Deposits"". The first map shows the known sand and gravel resources and their quality. The second map indicates selected sand and gravel resources of primary, secondary and tertiary significance. The third map indicates both bedrock resources and bedrock areas suitable f or extraction. These maps and the text are prepared in a formal suited for use by planning personnel.Recently, the Aggregate Resources Inventory Program has undergone evolutionary changes. New sources of data are being utilized in the inventory reports; in particular, detailed field assessment by inspecting, sampling, drilling and backhoe pitting. Liaison and joint assessment with district and regional Mineral Resources staff of the Ministry of Natural Resources, and personnel of the Ministry of Transportation and Communications, are key components of the Program.Twenty-two reports were available to the public as of December 1980, with a further thirty-six awaiting publication. Our present production rate is 3.5 reports per month. The reports appear to be well accepted by the municipalities and have proven effective in conserving prime aggregate resource areas.IntroductionThe urbanization of Southern Ontario has resulted in a major increase in the production of industrial minerals, such as sand, gravel, clay, shale, gypsum and stone, for use as cru shed aggregate, building stone, lime and cement.Although mineral aggregate deposits are plentiful in Southern Ontario, they are fixed-location, non-renewable resources. The potential for extractive development is usually greatest in urban fringe areas where land-use competition is extreme. Comprehensive planning and resource management strategies are required to make the best use of available resources, especially in those areas experiencing rapid development. Such strategies must be based on a sound knowledge of the total mineral aggregate resource base at both local and regional levels."

Jan 1, 1982

By S. R. Izatt

The use of MRT, a highly selective separations technology, has long been demonstrated to be a cost effective, efficient, and environmentally sound process for extraction of a wide range of anions and cations that are commonly found in copper electro - refining and electro - winning circuits, as well as in environmental treatment operations. This paper provides an update of commercial MRT applications in the copper industry. Several recent installations and test programs are reviewed including recovery of bismuth from tank house electrolyte, and from chloride matrix selenium reduction solution which is generated in the anode slimes treatment process. Recovery and refining of platinum group metals originating in the anode slimes is also discussed. Various other base metal and other target separations of interest to the copper producer are also reviewed. The recovery products are high purity metal salts which can be marketed directly or readily reduced to metal.

Jan 1, 2007

By Pierre Boulanger

This paper describes a generic technology for modeling in real time the various operations of surface mines. Based on various sensor fusion techniques and high-speed network, a virtual reality model of a mine capable of representing not only static infrastructures but also mobile equipment such as trucks and excavators is created. The modeling technique deal with a wide range of sensors such as survey data, satellite pictures, ore concentration, machine condition indicators, video, sound, real-time GPS locator, range sensor, etc. The model created allows for every piece of information to be displayed in context allowing for a better temporal and spatial correlation of events by mine operators, planners, and supervisors. Syncrude, a Canadian mining company located in northern Alberta, is planning to use this technology, not only to understand oil sands mining processes better, but also to give decision-makers better access to the timely, accurate information from the field that they need to make informed decisions.

May 1, 2001

By Muhammad Zaka Emad

ABSTRACT: Sublevel stoping mining methods with delayed backfill employs cemented rockfill (CRF) as a backfill material. It is used in underground mines to achieve ground control and reduce wall slough. In addition CRF serves to reduce development waste and provides a working surface for mining the upper levels. Efforts to optimize CRF practices have been published. This paper presents a detailed review of CRF practices in open stoping mining systems with reference to case studies. A new methodology is suggested in a simple stepwise approach, which can be adopted for site specific conditions. The need of laboratory testing and quality control program is discussed based on the published literature.

May 1, 2013