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By W. Petruk

"D. Doyle How large is the beam to which you referred? Are we considering Watts, Griffis the probe of a 1 micron sized particle?& McOuatReply Yes. The beam would be about 1 micron. We could enlarge or reduce it depending on the current in-put.D. Doyle Then chemically bound material we might not see. If you are restricted to 1 micron then you would not be able to separate things smaller than this. Is this not so?Reply We won't be able to analyse it but we will see it as the scanning electron microscope has a resolution down to about 0.1 microns. We should be able to get the general composition of such a grain plus its surrounding grains. We feel we can then make a reasonable estimate if it were as small as 0.1 microns. An accurate analysis would be achieved with grains of 3 and 4 microns.D. Doyle Would this have an application in the hydrocarbon field?Reply The lowest atomic number would be sodium. We wouldn't be able to go below that atomic number. Anything with sodiumor a larger atomic number would enable us to analyse the carbon.M. Fairwether Do you have any policy relating to priorities. For instance areCominco companies going to be limited in the amout of samples permitted to give everyone a chance because quite frankly our company, and I'm sure all base metals companies can hardly wait for the installation of this equipment. I can forsee two years back-log of work in the first month.Reply Quite frankly, I haven't looked at this. At the present time the work is under the START program but I suppose we will have to look at possible changes. Anything under the START program has first line priority.B. Thorndycraft Will the briquetting of samples be automated as well? Pinson MiningReply No, not at this point. Our polish section laboratory is first-class and can turn out 18 polish sections a day which is more thar we can handle.B. Thorndycraft With the capability of this machine to operate in a hands-off manner perhaps it could start to look for the 5 micron gold particle in tailings?Reply I have such a program using a wave-length spectrometer rather than the energy dispersive. The wave-length spectometer is about 10 times as sensitive and would scan the section much faster. A one inch diameter polished section would be scanned in about 7 hours for anything 1 micron or larger."

Jan 1, 1984

By D. B. Stewart

This paper reports on an investigation undertaken to determine the exhaust gas temperatures of operating underground mining equipment. The effectiveness of platinum catalytic purifiers is discussed. From exhaust temperatures, it is concluded that LHD engines are highly loaded, haulage truck engines are moderately loaded and utility vehicle engines are lightly loaded.

Jan 1, 1979

By Karina Forster

Open stope design depends on the ore body geometry, loading conditions and rock mass properties to estimate stope dilution and ground support requirements. Rock mass conditions for design primarily rely upon estimates of well established rock classification systems. Many sources of data exist for obtaining estimates for these rock mass classification values which include core logging, geotechnical mapping, geological mapping as well as linking one classification system to another through the use of empirically derived equations. The extent of mapping coverage can also vary significantly based on the data collection technique. This paper proposes an approach where individual components of rock mass classification systems are collected by the different available data collection techniques. Data from different rock types are also considered separately based on their alteration characteristics and general observation products. Data from the Cameco Corporation Eagle Point Mine is presented and an approach is outlined for obtaining average representative classification values for stope hanging wall characterization. The effectiveness of this approach is demonstrated through the analysis of a data base of hanging wall dilution information.

Jun 1, 2012

By Tatsuya Oki

Tantalum capacitors can be found mounted on printed circuit boards of domestic appliances such as personal computers. These capacitors contain a considerable quantity of expensive metal tantalum and can be detached and liberated from printed circuit boards by impact breakers. In this study, the size and density distribution of the liberated electronic devices were investigated. Then, tantalum capacitors were recovered from other electronic devices using size separation and pneumatic gravity concentration methods. More than 70% of Newton's separation efficiency was obtained for tantalum capacitors. High Newton's separation efficiency could be also obtained for other types of electronic devices such as chip resistors.

Jan 1, 2011

Mirador - Overview ? Located in Andean foothills of SE Ecuador ? Copper-gold porphyry hosted by calc-alkaline Late Jurassic granitic and porphyritic rocks ? 438 MT of 0.61% Cu and 0.19 g/t Au measured and indicated resources (at 0.4% Cu cut-off) ? Additional inferred resources of 235 MT of 0.52% Cu and 0.17 g/t Au ? Initial 25,000 tonnes/day production, expanding to 50,000 in year 6 320 MT of 0.62% Cu, 0.2 g/t Au ore mined at an average 1.4:1 strip ratio over a 21 year mine-life

May 1, 2006

By W. Beres, M. Bielawski

Recent research on the development of erosion resistant coatings has been directed to the finite element modelling of the behavior of coating and substrate, and their interface under the impact of eroding particles. The approach presented in this paper is based on advanced computer simulation techniques using ABAQUS/Explicit to investigate stress and strain at the surface and at the coating/substrate interface of multilayer coatings under single particle impact. It was found previously that solid particle erosion mechanisms are predominantly governed by the kinetic energy of the impacting particles. However, recent modelling efforts revealed that effects of various material models could be also significant. Therefore, different material models representing relevant coating and substrate properties were investigated and the effects of these models on the coating/substrate response were studied. Particularly, differences between elastic, elastic-plastic and brittle cracking model responses were assessed.

Jan 1, 2006

By L. Voisin, K. Yamaguchi, D. G. Mendoza, K. Ltagaki

The behavior of arsenic and antimony in the Cu-0 system was thermodynamically investigated to understand their elimination during a blister-making stage in copper smelting. Firstly, the phase relations in a miscibility gap composed of the liquid slag and copper phases in the Cu-0-As and Cu-0-Sb systems at 1523 K were established by a quenching technique. It was found that arsenic and antimony distributed preferentially into the slag phase in the miscibility gap. Secondly, the activities of arsenic and antimony in the miscibility gap of these systems were determined at 1523 K by using a double Knudsen cell - mass spectrometer method. It was clarified that the activity of arsenic in the copper and slag phases showed the negative deviation from ideality while that of antimony in the copper phase a slightly positive deviation. These data obtained in this study suggest a possibility to eliminate arsenic and antimony by means of over-blowing in a converter after discharging the slag.

Jan 1, 2007

By Jaime Meléndez Martínez

Recent interest in unconventional reservoirs motivates our work in laboratory measurements of seismic anisotropy. Seismic anisotropy is the variation in speed of a wave as a function of its direction of propagation. Analyzing anisotropy in unconventional reservoirs is important since anisotropy leads, for example, to differential stresses upon loading and could affect hydraulic stimulation (Reinicke et al., 2010, Zimmermann and Reinicke, 2009); in this sense, laboratory measurements are an important tool to study seismic anisotropy at small scales which can aid in the characterization of larger formations. The purpose of this work is to describe the laboratory methodology used to simultaneously measure ultrasonic P and S-waves in three different directions from a single core sample. Elastic anisotropy of a Proterozoic sedimentary rock from south-west Alberta is investigated. In metamorphic rocks seismic anisotropy is caused by preferred mineralogical alignment or foliation. Assuming a transversally isotropic medium, arrays of compressional and shear piezoelectric ceramic transducers were mounted on a sample trimmed from a core to measure travel times of ultrasonic P-waves and S-waves as a function of confining pressure at directions perpendicular, parallel, and oblique to the plane of foliation (bedding). Results show strong anisotropy agreeing with the assumption of a transversely isotropic medium. Dependence of travel times and hysteresis effects can be observed when pressurizing and depressurizing.

Jun 1, 2012

By M. Jackman

"Froth stability is critically important for an effective separation of fine and ultrafine particles using column flotation. While a desirable froth stability is required to facilitate the drainage of entrained gangue particles for secondary cleaning, excessively stable froths could create problems in separation efficiency and down-stream processing. In this work, we demonstrate that a stable foam was produced using a poly (N-isopropylacrylamide) (PNIPAM) solution at the temperatures below the critical solution temperature. In contrast, very little foam was produced at the temperature above the critical solution temperature (~32 oC) of PNIPAM. We can also tune the foam stability by changing the temperature of wash water. When warm water of temperature of 50 oC was applied, the foam collapsed and diminished. This is probably attributed to the switching of PNIPAM molecules from coiled to a globule conformation as the temperature is increased. Our results indicate that the foamability and foam stability can be tuned by tempartureresponsive PNIPAM. This is the first time that thermo-responsive PNIPAM has been shown to have potential as a modifier of froth stability in column flotation.INTRODUCTIONIn mineral processing, column flotation has become a more prevalent process in the separation of fine mineral particles (typically < 100µm). Traditional flotation cells are sometimes less efficient in selective separation of ultra-fine particles (Kohmuench et al., 2009). The efficiency of flotation columns is dependent on the froth stability at the top of the cell to drain the unwanted gangue particles entrained in the froth. The greater froth height in flotation columns, compared to mechanical flotation cells, gives a longer froth residence time, allowing more of the drainage process to take place before the froth reports to the launderer. Secondary cleaning, by applying a wash water shower to the froth, enhances drainage of gangue particles entrained in the froth, and improves the recovery of the targeted minerals (Finch et al., 2007).While a stable froth is desirable to facilitate drainage of entrained gangue particles, greater amounts of fine particles have been found to contribute to excessively stable froths which could create problems for down-stream processes (Bethell et al., 2012). Operators have tried spraying additional wash water on the froth, and reducing frother dosage to destabilize the froth and to prevent backup at the launderer. The former is sometimes inefficient, and the latter results in unacceptable recovery loss. Currently, the best practice is often the installation of larger froth launderers, adding expensive defoaming agents, and/or using deaeration tanks (Bethell & Luttrell, 2005)."

Jan 1, 2016

By Norman Orr, J. W. Gregg, Jack Wahl

The Pembina Cardium pool is a low permeability, stratified, solution-gas drive reservoir. Water-flooding has proven to be an effective means of pressure maintenance for all areas of the pool in which an economic rate of water injection can be maintained. The majority of water injection wells in the pool are converted oil well~ with capacities greater than 100 millidarcy-feet. If the average injection rate per unit of capacity can be in-creased the lower capacity areas of the pool can be economically flooded. Theory, laboratory work, and two . early miscible-flooding projects with-in the pool suggested that average water injection rates for converted wells could be increased two to three-fold by the initial injection of natural gas liquids and natural gas. How-ever, these two early projects received volumes of natural gas liquid!:' and high-pressure natural gas which would be economically prohibitive for routine stimulation. Area D, one of the Five-

Jan 1, 1962

By A. H. Lang

"The Cordilleran region of western Canada includes most of British Columbia and the Yukon and pares of Alberta and the Northwest Territories. The western part of this region was for about 50 years the principal mineral producing area of the Dominion. It lost this distinction in 1907 when production from the mines of the Canadian Shield took the lead, but it continues to provide about 15 percent of the total Canadian production. In 1945 the total mineral production of British Columbia and the Yukon was valued at $65,302,900, of which about 80 percent was derived from metals.This paper is intended to serve as an introduction co the more derailed Cordilleran papers. Part I includes a brief synopsis of the complex geology and diverse types of mineralization in the region and Parr II collates the main structural principles exemplified in the derailed papers, and draws some conclusions regarding the application of this information to prospecting."

Jan 1, 1954

A semi-automatic device has been constructed that can be used to check the solution strength of cyanide solutions. It consists of a wheel on which a gold-foil-bearing glass slide is mounted. The wheel moves the gold foil through the solution under test and intercepts a light beam. As the gold foil is attacked by the cyanide solution its light absorption diminishes. The successive in-crease in transmitted light intensity is recorded and gives a measure of the gold dissolution rate. Curves have been obtained to show the effect of cyanide concentration and oxygen content on dissolution rates. Details are presented of the construction of the unit, and some practical operating procedures are outlined. 0 NE of the important, although often neglected, factors in the extraction of gold by cyanidation is the actual dissolving strength of the cyanide solution. This depends in a

Jan 1, 1964

By A. E. M. Warner, P. J. Mackey

Copper metal is produced in large or small tonnages in almost all countries of the world—handling raw materials in the form of either as-mined or milled ores, custom concentrates, or other custom materials including scrap and recycled copper. The scale of operations and type of technologies used around the world varies widely. There is a certain concentration of both mining and smelter-refinery production as a total of ten countries produce some 80% of world mined copper, while ten countries—mostly different ones— produce about 80% of smelted and refined copper. As a result, international copper trade is significant. The present paper takes the reader on a virtual tour of the copper plants throughout the world with a focus on smelter facilities. Operations and technology employed at each plant visited are discussed including a brief historical sketch. Future trends identified during the world tour are also discussed. The present authors considered sufficient time was required for a thorough study tour and settled on eighty days—the same as that for the celebrated fictional story of world circumnavigation in the 1870s. INTRODUCTION The celebrated French writer Jules Verne published his book “Around the world in 80 days” in English in1873 and it is the story of Phileas Fogg and his French valet Passepartout circumnavigating the world in 80 days in the fall of 1872 on a £20,000 wager (equivalent to over 2 million pounds today) from the exclusive Reform club in London. This is an interesting period for copper as it started trading on the London metals Exchange in 1876 and the start of global copper production chains started to take off at this time with the rapidly increasing electrification of the world. The production chain includes mining, mineral processing, smelting, refining and fabrication. Since 1880 annual world copper production has increased by over 150 times from 154,000 tonnes in 1880 (nominally considered as smelted copper—essentially the only route at the time to marketable copper) to over 23 million tonnes today (including total refined copper of 19 million tonnes of smelted copper including scrap and 4 million tonnes by solvent extraction-electrowinning), in tandem with increased electricity usage, along with significant transportation usage and for manufactured products (Figure 1).

Jan 1, 2019

By J. Shahabpour

"Abstract - Breccias with angular and rounded clasts of a late-mineralization, ""barren"" hornblende porphyry dike set within a comminuted matrix consisting of rock fragments and quartz, cemented by quartz and K-feldspar of hydrothermal origin is observed in diamond drill cores from the Sar Cheshmeh porphyry copper deposit. Studies of age relationship between vein types, phyllic-altered clasts and the breccia groundmass suggest that the brecciation is a late event. The breccia clasts record evidence of hydrothermal reaction between the clasts and fluids responsible for the brecciation.Formation of bornite, in the breccia clasts of the originally barren hornblende porphyry dike, and in the breccia matrix, along with the scarcity of bornite in the Sar Cheshmeh deposit itself suggest involvement of fluids which are later and of different composition from the fluids responsible for the known mineralization at Sar Cheshmeh. These later fluids may be related to a later plutonic event and suggest the possibility of a later, and concealed deposit."

Jan 1, 1994

By Doug Milne

Linking Classification Systems with each other Similar Parameters between systems Different Rock Mass Properties Rock Mass Classification parameters and geology Different sources of data Commonly Used Rock Mass Classification Systems Q? = Q with SRF = 1.0 RMR? = RMR with no joint orientation correction RMR76 = 9lnQ + 44 RMR?76 = 9lnQ? + 44 RMR76 = RMR89-5 RMR?76 = GSI = RMR89-5 MRMR = ??MRMR

May 1, 2013

By Nader Golchinfar

The V-shaped breakout zones around excavation boundary have been captured by a variety of numerical methods such as FEM and DEM methods and failure criteria such as linear Mohr-Coulomb and non-linear Hoek-Brown failure criteria. Diederichs (2007) used Hoek-Brown parameters in his spalling parameter approach; however, it is convenient to use the Mohr-Coulomb failure criterion in numerical modeling because the material parameters can easily be determined from triaxial tests. It is shown in this study that when peak and residual strength parameters as well as dilation angle are properly defined, the brittle Mohr-Coulomb failure criterion can be used to model depth of failure near underground excavations satisfactorily.

Jun 1, 2012

By K. S. Fraser, H. J. H. Pieterse

"A pressure oxidation plant to pretreat refractory sulphide ore at the Goldstrike plant in Nevada, was commissioned in early February 1990. The plant, with a nominal capacity of 1363 t/d, was commissioned over a one-week period and achieved design capacity and availability within ten weeks an unusually short period for a plant of this complexity.The pressure oxidation process is conducted under elevated temperature and pressure conditions, and in a corrosive environment. These conditions demand that the process and engineering design of the plant be carried out in a much more sophisticated and detailed manner than is normally required in a conventional gold plant.This paper provides an account of the process and engineering design of the Goldstrike pressure oxidation plant with special emphasis on the design of the vessels, slurry pumps, piping, valves, and control systems.BackgroundLocationThe Goldstrike property is located in Eureka County in northcentral Nevada on the Carlin geological trend. The mine is approximately 40 km northwest of the town of Carlin which is situated on Interstate Highway 80. The minesite is located 1700 m above sea level in the Tuscarora Mountains.Initial Goldstrike OperationsShallow, low-grade mineralization was discovered by diamond drilling in the Goldstrike area in the 1960s. A heap leach operation was established in the mid-I970s by the previous owners. The Post deposit was discovered in 1982. Gold production by mining and heap leaching reached I t/a (40 000 oz/a). American Barrick purchased the property in 1987 and started an aggressive program of deep drilling. This led to the discovery of the Betze and Deep Post deposits and established sufficient reserves to justify an initial 4100 t/d mill and a 5 500 000 t/a heap leach operation"

Jan 1, 1992

By S. Torres, J. Álvarez, R. Castillo, R. Fuentes, C. Sandoval, R. Parra, Myakalwar A. K., M. Velázquez, J. Yáñez, D. Sbarbaro

Rapid analytical assessment in copper mining industry is a limiting factor for operational purposes and for the improvement of processes. The present work aims to review the analytical assessment in the copper industry utilizing emerging spectrochemical techniques such as laser induced breakdown spectroscopy (LIBS) and UV-Vis-IR Hyperspectral Sensing. LIBS is a plasma based spectroscopic method where the sample surface is irradiated by high power laser. The light emitted from the plasma contains atomic -molecular spectral information and can be detected using a simple CCD based spectrometer. UV-Vis-IR Hyperspectral Sensing is produced by the reflection of light from the sample’s rough surface in all directions and it can be collected by using an ellipsoid or paraboloid mirror arrangement. The electromagnetic radiation emitted by the samples in the UV-Vis, NIR and MIR region can be used for molecular characterization. The spectrometer splits different wavelengths through a CCD arrangement in 2D spatial and spectral dimensions, thus a hyperspectral cube of data is generated. Chemometric techniques such as principal component analysis (PCA), K- nearest neighbors (KNN), support vector machine (SVM) among others, can be applied to LIBS and Hyperspectral data for better classification and quantification purposes in copper ores. Real- time determination of elemental and mineral species used for online processing control will help to achieve the copper industry 4.0. INTRODUCTION The demand for copper mineral resources is intensely growing with the increase in population, per capita GDP, the development of new technologies and the increase in global living standard. With the rise in consumption of copper, it is important to optimize mining and metallurgical processes tending to the copper industry 4.0 (Ge, Song, Ding, & Huang, 2017). The real-time analytical assessment in the mining and metallurgical processes is a crucial part for allowing the global improvement in mining industry. The features considered for better analytical assessment are the instrumental automation and interconnection, real time results, low cost, quality in terms of accuracy and precision. Furthermore, improving recovery (extraction), timing and quality of final products avoiding environmental impacts. Some elements such as Cu, Fe, Ag, Au, Mo, S, As, Pb, Zn are important to be determined in the process control. Additionally, rapid mineral identification of few species such as CuFeS2, Cu4FeS5, FeS2, CuS, Cu2S, MoS2, Cu3AsS4, FeAsS, among other can be challenging.

Jan 1, 2019

By B. Rivard, D. Francis

A layered Archean magma chamber is exposed at the base of the Yasinski segment of the La Grande greenstone belt. This intrusive complex lies beneath a sequence of mafic volcanics and is underlain by granitoid basement which is crosscut by a swarm of gabbroic dykes. The gabbros of both this complex and the dyke swarm of gabbroic dykes. The gabbros of both this complex and the dyke swarm define a pronounced Fe-enrichment trend. The volcanic patterns of the La Grande and Eas tmain greens tone belts, however, define a series of iron depletion trends which originate in the iron enrichment trend of the gabbroic intrusives. These patterns suggest that the gabbros produced in the intrusive complex may serve as parental liquids for some of the lava suites of the James Bay greens tone belts.

Jan 1, 1984

By E. L. Chanturiya

The research and characterisation for compositional, physicochemical, structural, electrical and flotation properties of various pyrite samples for a copper-zinc sulfide ore was carried out. Various methods were used during the research, such as optical microscopy, X-ray diffraction, electron probe micro-analysis (EPMA), phase emission analysis, routine chemical analysis, auger electron spectroscopy (AES), scanning electron microscopy (SEM), back-scattered electron images (BSE), potentiometry, and instrumental neutron-activation analysis, flotation. Analysis of obtained results established the interrelation between impurity structures and concentration of electric charge carriers in minerals, Butyl xanthate sorption and flotation yield of pyrite. The research concluded that pyrite samples differ by morphology, micro defects of structure, concentration of donor and acceptor impurities (Co, As, Sb, etc.) and conductivity parameters (thermo-electrical force, specific resistance and concentration of charge carriers The peculiarity of pentagon-dodecahedral pyrite is the high concentration of electric charge carriers (electrons) and the more negative surface potential (by 25–75 mV) in comparison to cubic pyrite. The surface of cubic varieties is more active, therefore it is oxidized in alkaline lime medium much faster, than the surface of pentagon-dodecahedral varieties. This phenomenon is caused by high reaction ability, irregular jointing and defects of cubic pyrite. This promotes the increase of calcium ion sorption on its surface and the decrease of Butyl xanthate sorption. According to this, an increase in alkalinity (lime medium) from a pH of 10.0–11.5 leads to an increase of gold content reporting to the tail of bulk flotation. Gold content is increased from 0.58 g/t (?? 9.5) to 1.9 g/t (?? 11.6), which represents an increase in gold recovery of 24.68 to 79%, respectively.

Jan 1, 2016