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Since 2008 rapid advances have been made in technologies for the sensing and sorting of ores, particularly copper, and copper-related ores. Advances include significant increases in the sensitivity and throughput, specifically in the area of bulk sorting. Such advances were not possible without contemporaneous advances in the understanding of copper orebodies, in particular the understanding and quantification of the heterogeneity required within an orebody to support an effective sort, regardless of the technology deployed to do this. This paper covers fundamental knowledge in the characterization of orebodies and their ores for sorting; relationships between measures of heterogeneity and sorting response; the design of bulk sorting systems that can exploit this heterogeneity to add value to copper operations; and, a quantification of the value that can be generated from bulk sorting at a case study mine. INTRODUCTION Society currently puts increasing pressure on industries to move towards cleaner and more efficient means of production, and the mining industry is no exception. Mining additionally faces other factors increasing the pressure to be more efficient: high-grade and easily accessible reserves have become largely depleted, therefore the mined grade at operations across most commodities, including and in particular copper, is decreasing. Additionally, the grade of new discoveries in the sector continues to decrease (Schodde, 2011). Factor in the high capital cost of processing facilities and the low levels of efficiency of current grinding circuits, and the situation for such mines becomes dire. Sorting, by maximizing the amount of ore extracted while simultaneously reducing the waste content in ore delivered to downstream processes (whether simply transport and crushing, or more sophisticated circuits such as grinding and flotation or leaching) has long been of interest to mining operations and projects struggling with low margins (Bamber, 2012). However, until recently sorting technologies that are both cost effective and effective at such high throughputs have not been commercially available.

Jan 1, 2019

By J. W. Hohn

The precipitation of Fe(III) to form ferrihydrite in the presence of arsenic is the United States EPA's Best Demonstrated Available Technology for treating arsenic-containing hydrometallurgical solutions and waste streams. This technology has been widely adopted throughout the world and developments have been well reviewed. The adsorption and long-term stability of ferrihydrite can be improved by co-precipitating Fe(III) and Al(III) together to form an aluminum-modified ferrihydrite. Arsenate adsorption into ferrihydrite and modified ferrihydrite as a function of pH, Fe/As or (Al+Fe)/As mole ratio, and the initial As(V) concentration is presented and compared. The results of long-term aging of both adsorbents at 70°C for over a year are also summarized.

Jan 1, 2006

By M. M. Helm

Samples sourced from the Goldstrike property in Nevada USA, have been evaluated in terms of their preg-robbing capacity and the physical structure of the graphitic carbon component in the carbonaceous gold ore. The study highlights a wide range in preg-robbing capacity between samples collected from the Betze-Post open pit and Rodeo underground mine. The physical structure of the graphitic carbon was assessed using Raman spectroscopy, and is found to play an important role in influencing preg-robbing behaviour. Differences observed in the physical structure of graphitic carbon are thought to be the result of hydrothermal events that occurred at Goldstrike.

Jan 1, 2011

By A. Roy, T. LeBel, P. Coursol, P. Lind

At the early stage of a mining project, small amounts of concentrates are available for testwork. For gold concentrate or ores containing significant arsenic levels, batch bench scale roasting is often unreliable, leading to highly variable gold recoveries to be used in the project’s financial justifications. With an appropriate bench scale unit using continuous feeding and residence time control for solid and gas phases, reliable numbers can be obtained at small scale with only a few hundred grams per test condition. This paper describes the development of a pilot fluid bed roasting unit by Kingston Process Metallurgy Inc. (KPM) to perform representative trials on gold concentrates containing arsenopyrite, arsenian pyrite and carbonaceous components. Calcines produced under different conditions were characterised by chemical analysis and electron microprobe; the calcine microstructure obtained is described. The most important parameter affecting gold recovery is oxygen content in the roasting atmosphere, with the lowest controlled oxygen level giving the highest gold recoveries. Higher local temperatures in the bed may cause the formation of molten glassy phases which can also reduce the gold recoveries significantly. The impact of roasting conditions in the two inch fluid bed is compared with commercial results obtained in full scale operation.

Jan 1, 2014

By Rénard Chaigneau

Quality during induration Drying ??40% of energy ??Drying velocity = f(1/radius2) ??Size versus risk of condensation ??Flow is important (minimise fines)Oxidation ??IOC Fe2+ typically 0.04% ??Important to minimise Fe2+forLow Temperature Disintegration ??Tight size distribution is key13

May 1, 2011

By Arsenio Enriquez, Adrian Deneys, Ryan Walton, Jenny Esker

NOx emissions at the Rio-Tinto Kennecott Copper (RTKC) smelter, near Salt Lake City, Utah, are regulated to a compliance emission limit at the Main Stack of 15.9 kg/hr on an annual rolling average. The paper discusses RTKC efforts and improvements, particularly related to the anode furnace operations, since the Smelter modernization in 1995 to comply with the air quality approval limit. This includes replacement of gaseous ammonia to Steam-Gas Refining (SGR) system during the copper reduction stage, upgrade anode furnace oxygen-fuel burner from Praxair’s Stabilized Jet (S-J) to Jet Lance (J-L) technology, development and implementation of operational best practices and continuing to investigate and evaluate NOx control technology and strategy in the industry. In early 2016, changes to Praxair J-L Burner technology on both anode furnaces, utilizing wider lance spacing, was adopted and further improved NOx emission levels well below the compliance limit. INTRODUCTION Since the establishment of the Clear Air Act in 1970, the Environmental Protection Agency (EPA) has been regulating emissions of nitrogen oxides (NOx) to reduce impact on public health and the environment (USEPA, CAA, USEPA, NAAQS). As a requirement of the Clean Air Act, the EPA evaluates the standards for NOx and criteria pollutants on a periodic basis and as a result, standards have been revised and ultimately reduced over time (USEPA, CAA, USEPA, NAAQS, UDAQ, SIP). To remain competitive with changing regulations and in conjunction with Rio Tinto environmental standards for continuous improvement, the RTKC smelter has been motivated to research and implement NOx control strategies. NOx health and environment impacts NOx refers to a group of seven compounds including the most common, nitrogen dioxide (NO2). (USEPA, NO2). The EPA enforces both short-term (1-hr average) and long-term (annual average) standards for NO2 to protect against associated respiratory system impacts. Short-term exposure of elevated NO2 concentrations can aggravate respiratory diseases and lead to symptoms such as coughing, wheezing or difficulty breathing while longer exposures may contribute to the development of asthma and potentially increase susceptibility to respiratory infections. (USEPA, NO2) Additionally, NOx is necessary in the formation of ozone and particulate matter less than 2.5 microns (PM2.5). Ozone concentrations can negatively impact lung function and in some cases, contribute to chronic obstructive pulmonary disease. (USEPA, Ozone) The particles associated with PM2.5 can reduce lung capacity and aggravate heart conditions. (USEPA, PM2.5) For all NOx related pollutants, children and the elderly are generally at greater risk for the health effects. (USEPA, NO2, USEPA, Ozone, USEPA, PM2.5)

Jan 1, 2019

By J. Cayouette, C. Bolduc, P. Blatter

"The LaRonde mill was commissioned in 1988 and began treating ore from the Penna shaft in 2000. The mill has been expanded to accommodate 7,500 t/day, but ramped down to 6,000 t/day since the deep extension began. The process recovers gold, silver, and base metals. In 2008, the Goldex plant began trucking gold-pyrite concentrate to a treatment plant feeding pulp to the LaRonde mill, increasing gold output by 40,000 oz. In 2009, the high-grade Lapa ore processing facilities were annexed to the LaRonde plant, increasing gold output by 120,000 oz. This paper outlines the metallurgical considerations related to the treatment of different ore types.RÉSUMÉ Le concentrateur de la mine LaRonde a été mis en service en 1988 et a commencé à traiter le minerai du puits Penna en 2000. La capacité du concentrateur a augmenté afin de permettre le traitement de 7 500 tonnes de minerai par jour, capacité qui est retombée à 6 000 tonnes par jour (tpj) depuis le début de l’extension en profondeur de la mine. Ce procédé permet de récupérer de l’or, de l’argent et des métaux communs. En 2008, l’usine de traitement Goldex a commencé à transporter par camion du concentré de pyrite et d’or vers une usine de traitement alimentant en pulpe le concentrateur de LaRonde, augmentant ainsi la production d’or de 40 000 onces. En 2009, les installations de traitement du minerai à haute teneur de Lapa ont été annexées à l’usine de traitement de LaRonde, augmentant la production d’or de 120 000 onces. Cet article passe en revue les considérations métallurgiques liées au traitement de différents types de minerai."

Jan 1, 2017

By Sabry A. Sabour

Metal price is among the key variables in the open pit optimization and the economic evaluation process. The common approach to handle metal prices in open pit mine planning is to optimize the ultimate pit and the mining schedules using a fixed, flat metal price. In this respect, metal price is assumed to be known with certainty throughout the entire mine life, which in some cases can reach 80 years. Given the volatile nature of metal markets and the metal price cycles, the conventional pit optimization approach may generate sub-optimized mining plans, which results in either extra costs to mining projects or lost revenues, or both. Long-term operational decisions such as future pit expansions, beyond the currently optimized limits, cannot be handled using the pit optimization approach based on flat metal prices. There is a growing interest in the mining industry to model and manage such market uncertainty in the pit optimization as well as the project evaluations in order to maximize the value of mining operations. In this paper, the author will outline a practical approach to optimize the ultimate pit taking into account the volatility and variability of metal markets. The proposed approach uses a combination of the pit optimizer of the commercial MineSight package and a simulation-based economic modeling real options valuation approach employing the least-squares Monte Carlo algorithm. MineSight pit optimizer employs both the floating cone for initial optimization exercise and the standard Lerchs-Grossmann algorithm. In this paper, Lerchs-Grossmann option will be used to generate the pit shells. Real options valuation approach used in this study is based on generating multiple metal price scenarios. Metal price uncertainty is modeled using stochastic metal price models such as the geometric Brownian motion and the mean-reverting process. The mining operational scenarios corresponding to the simulated metal prices are then optimized using the least-square Monte Carlo approach. The objective is to maximize the discounted cash flow value of the project while incorporating the operating flexibility to revise the operating status of the open pit with time as new information becomes available. The focus of this work is on the practicality of the proposed uncertainty-based pit optimization approach and the difference it can make to the technical operational mining decisions. A case study of a hypothetical open pit poly-metallic mine is provided. The deposit contains copper, gold and silver grades. The run of mine ore is sent to the process plant that produces copper concentrate with copper as the main metal and gold and silver as the by-products. Four uncertain variables are considered here include copper, gold, silver prices and foreign exchange rate. Both copper price and exchange rate are modeled using the mean-reverting process while gold and silver prices are modeled using the geometric Brownian motion. The case study is performed using both the conventional flat price pit optimization approach and the proposed uncertainty-based one to compare results.

Aug 1, 2013

By Catharine E. G. Farrow, David H. Watkinson

The Ni-rich Epidote Zone of the Fraser Mine at Sudbury is characterized by alteration assemblages rich in epidote, actinolite and magnetite which are roughly concentrically zoned and up to hundreds of meters in length. These zones form discrete areas within the igneous Footwall Breccia below the Sudbury Igneous Complex. The assemblages grade from epidotized Footwall Breccia matrix,through actinolite-bearing rocks with few vestiges of original Footwall Breccia textures, into the most intensely altered rock, a magnetite-rich facies. Pentlandite, pyrrhotite and pyrite are the dominant sulfdeminerals; chalcopyrite is minor. The strongest geochemical differences compared to original Footwall Breccia occur where epidote and actinolite dominate the alteration assemblage (EPDZact facies). The most intense alteration facies are typifed by low Cu/(Cu+Ni) values of <0.1. Strong positive correlations exist between Ni and Co, Cu and Au, and among Ir, Os, Ru and Rh. Chondrite-normalized Ni - PGE -Au - Cu plots display an overall increase in all elements from the least to the most intensely altered facies except for Au and Cu. As the proportion of actinolite increases in the EPDZact facies, the chondrite-normalized profles fatten considerably due to low Au and Cu contents. Abundances of Ni, Ir, Ru and Rhalmost ubiquitously increase with degree of alteration. In contrast, Cu, Zn, Ag and Au contents are low in almost all facies. It is suggested that saline hydrothermal fluids moved through the Epidote Zone formation and became more oxidized as they reacted with the Footwall Breccia and with footwall units, including ultramafic rocks. As this trend continued, magnetite-rich zones eventually developed. The occurrence of calcite locally in these magnetite-rich zones suggests that the pH of the fluid increased, causing Cu solubility to drop as activity in the hydrothermal system waned. Sudden changes in fluid composition such as this may have been due to an influx of fluid from bounding ultramafic rocks. Hydrothermal activity was focused along the margins of footwall ultramafic units. Individual hydrother-mal cells may have formed in the Footwall Breccia along pre-existing structures or sulfde concentrations. Metals may have been scavenged from sulfide-bearing Footwall Breccia and possibly Sublayer rocks. Nickel and some PGE were deposited in the Epidote Zone, whereas Cu, Au and Ag continued out-ward into the footwall where they were deposited as Cu-rich footwall veins. Copyright © 1996 Canadian Institute of Mining, Metallurgy and Petroleum.

Jan 1, 1996

By Catharine E. G. Farrow, David H. Watkinson

Abstract-The Ni-rich Epidote Zone of the Fraser Mine at Sudbury is characterized by alteration assemblages rich in epidote, actinolite and magnetite which are roughly concentrically zoned and up to hundreds of meters in length. These zones form discrete areas within the igneous Footwall Breccia below the Sudbury Igneous Complex. The assemblages grade from epidotized Footwall Breccia matrix, through actinolite-bearing rocks with few vestiges of original Footwall Breccia textures, into the most intensely altered rock, a magnetite-rich facies. Pentlandite, pyrrhotite and pyrite are the dominant sulfide minerals; chalcopyrite is minor. The strongest geochemical differences compared to original Footwall Breccia occur where epidote and actinolite dominate the alteration assemblage (EPDZact facies). The most intense alteration facies are typified by low Cu/(Cu+Ni) values of <0.1. Strong positive correlations exist between Ni and Co, Cu and Au, and among Ir, Os, Ru and Rh. Chondrite-normalized Ni - PGE - Au - Cu plots display an overall increase in all elements from the least to the most intensely altered facies except for Au and Cu. As the proportion of actinolite increases in the EPDZact facies, the chondrite-normalized profiles flatten considerably due to low Au and Cu contents. Abundances of Ni, Ir, Ru and Rh almost ubiquitously increase with degree of alteration. In contrast, Cu, Zn, Ag and Au contents are low in almost all facies. It is suggested that saline hydrothermal fluids moved through the Epidote Zone formation and became more oxidized as they reacted with the Footwall Breccia and with footwall units, including ultramafic rocks. As this trend continued, magnetite-rich zones eventually developed. The occurrence of calcite locally in these magnetite-rich zones suggests that the pH of the fluid increased, causing Cu solubility to drop as activity in the hydrothermal system waned. Sudden changes in fluid composition such as this may have been due to an influx of fluid from bounding ultramafic rocks. Hydrothermal activity was focused along the margins of footwall ultramafic units. Individual hydrothermal cells may have formed in the Footwall Breccia along pre-existing structures or sulfide concentrations. Metals may have been scavenged from sulfide-bearing Footwall Breccia and possibly Sublayer rocks. Nickel and some PGE were deposited in the Epidote Zone, whereas Cu, Au and Ag continued outward into the footwall where they were deposited as Cu-rich footwall veins.

Jan 1, 1996

By André Chagnon, Michel Malo, Benoît Dubé, Chantal Pelchat

"Abstract- In the southern Gaspé Appalachians, gold mineralization is spatially associated with the Acadian dextral strike-slip Grand Pabos-Restigouche fault system. Two different structurally-controlled gold prospects, the Lac Arsenault and the Saint-André-de-Ristigouche, are described to unravel the genesis of gold mineralization in this part of the Canadian Appalachians.At the Lac Arsenault gold prospect, gold mineralization consists of Au-As-Pb-Zn-Cu-(Ag) polymetallic fault-filled quartz veins with laminated textures emplaced in brittle-ductile sinistral X shear fractures. Mineralized veins are hosted by Middle Ordovician graywacke of the Arsenault Formation, belonging to the Dunnage Zone, the Early Paleozoic oceanic domain of the Appalachians. Terrigeneous rocks of the Arsenault are regionally metamorphosed at the lower greenshist facies and the mineralized veins are included in a zone of Fe-carbonate alteration.The Sb-Au-As mineralization of the Saint-André-de-Ristigouche gold prospect, in the southwestern Gaspé area, comprises extension veins in the extension direction emplaced in brittle conditions. Mineralized veins are hosted by calcilutite and laminated silty and argillaceous limestone of the Early Silurian part of the White Head Formation, which belongs to the Gaspé Belt, the Middle Paleozoic successor basin in the Gaspé Appalachians. Metamorphic grade of the White Head Formation in the southwestern Gaspé area is very low, but the gold mineralization is included in a zone of hydrothermal propylitic alteration which includes two Cu-skarn mineral occurrences. The Lac Arsenault gold prospect has many characteristics of "greenstone-hosted quartz-carbonate vein" deposits whereas the southwestern Gaspé area, which includes the Saint-André-de- Ristigouche gold prospect, shows affinities with the geological setting of sediment-hosted gold deposits (Carlin-like deposits). The two gold prospects are controlled by the Grand Pabos- Restigouche fault system but they were not emplaced at the same level in the crust. Acadian strikeslip fauting played a major role in their respective genesis in providing channelways for ore-bearing fluids. The recognition of the analogy of the geological setting of the southwestern Gaspé area with that of Carlin-like mineralization gives new ideas for exploration in the area and elsewhere in the Appalachians.Résumé - Dans le sud des Appalaches de la Gaspésie, on trouve des minéralisations aurifères spatialement associées au système de failles de coulissage dextre acadien de Grand Pabos-Restigouche. Deux indices très différents, Lac Arsenault et Saint-André-de-Ristigouche, sont décrits pour évaluer la genèse des minéralisations aurifères à contrôle structural de cette partie des Appalaches canadiennes. Au Lac Arsenault, la minéralisation aurifère comprend des veines polymétalliques à Au-As-Pb- Zn-Cu-(Ag) en remplissage de failles. Ces veines à texture laminaire se retrouvent dans des zones de cisaillement fragiles-ductiles senestres de type X. Les veines minéralisées sont encaissées dans les grauwackes d’âge Ordovicien moyen de la Formation d’Arsenault appartenant à la zone de Dunnage, le domaine océanique du Paléozoïque précoce des Appalaches canadiennes. Les roches terrigènes de l’Arsenault sont métamorphisées régionalement au faciès inférieur des schistes verts et les veines aurifères sont dans de larges zones d’altération dolomitique (Fe-carbonate).Dans le sud-ouest de la Gaspésie, la minéralisation à Sb-Au-As de Saint-André-de-Ristigouche est dans des veines d’extension comprises dans la direction d’extension et mises en place dans des conditions de déformation fragile. Les veines minéralisées sont encaissées dans les calcaires argileux et les calcilutites de la partie silurienne de la Formation de White Head qui appartient à la ceinture de Gaspé, le bassin successeur du Paléozoïque moyen des Appalaches de la Gaspésie. Le degré métamorphique des roches du White Head est très bas, mais"

Jan 1, 1998

By T. E. Morimoto

Summary The Research Council of Alberta has made a series of tests with the cyclone washer to investigate the influence of the following operating variables: underflow apex diameter, .specific gravity of medium, pulp ratio, density distribution of the feed, and size analysis of the feed. The results obtained for all the variables studied, except size analysis of the feed, are included in this paper. The tests were made with smaller underflow apex diameters and lower specific gravity .suspensions than have been recommended by Cerchar for the sharpest separations. However, what is considered to be sufficiently good cleaning was accomplished with a suspension of 1.30 specific gravity and an underflow to overflow diameter ratio of 0.56. It was found that the sharpness of separation was not affected appreciably by variations in specific gravity of suspension or underflow apex diameter provided that the density of separation was within the normal range of washery operation. Cyclone performance was not too adversely affected by decreasing the pulp ratio. The minimum figure which gave reasonable separation was 4 to 1. The tests with various density distributions of feed revealed .that the degree of washing difficulty had no detrimental effect on the .sharpness of separation given by the cyclone. Introduction A major problem of the bituminous coal industry today is that of reducing the ash content of the finer sizes (minus 1/4-inch) of coal. This problem is particularly acute in Alberta, where, because of tectonic movement subsequent to deposition, the coals have been rendered friable, and bands of impurities have been intimately mixed with the clean material. As a consequence, most Alberta coals, as mined, contain a large proportion of fines and have a high inherent mineral-matter content. The advent of mechanized mining and stripping operations ?has further aggravated this problem.

Jan 1, 1952

By J. R. Rau

While refuge chambers are common place in most underground mining projects, there are different philosophies as to what life support systems are to be considered and how these systems are to be applied. Case studies in the underground mining industry have examples of emergencies where the external compressed air and power supply to the refuge chamber were compromised due to proximity of services to the fire location. In 2005, The Department of Industry and Resources, Western Australia, drafted guidelines that listed specific requirements for refuge chambers which included a secondary life support system that would operate independently of external sources. The objective of this document is to examine what critical life support systems are essential for safe entrapment in the event of an emergency and to examine considerations for their application.

Aug 1, 2013

By Keith Donovan

Why are we here? Improve equipment performance & health ? Eliminate undesirable downtime and expensive secondary damage ? Maximize equipment life, optimize running costs (reduce costs) ? Improve safety and environmental performance ? Capture and consistently apply equipment knowledge ? Improve Proactive Maintenance processes & practices

May 1, 2009

By Robert A. Creaser, David R. Lentz

Abstract - The Moss molybdenite deposit, which was mined during both world wars, is hosted in late Grenvillian granitic pegmatite dikes. These dikes are locally aplitic, and intrude the late tectonic Onslow syenite (probably correlative with the ~1090-1070 Ma Kensington suite), which is in turn intrusive into the 1170-1155 Ma Chevreuil intrusive suite of southwestern Quebec. A Re-Os model age of 1053 ± 4 Ma (8.3 ppm Re) was obtained for molybdenite from a pegmatitic veinlet within an aplitic phase of the dike. A much younger Re-Os date of 860.9 ± 9.2 Ma (6.9 ppm Re) obtained previously from a pyrrhotiteand pyrite-rich metasomatic vein might reflect Os diffusion during slow cooling of the Grenville province, because this age is consistent with K-Ar dates reported from the region. Alternatively, the similarity between these younger dates may be fortuitous, and may instead relate to sampling issues for molybdenite. The Mo-rich granitic dikes at the Moss deposit are similar to other Mo-rich A-type pegmatite-aplite granitic dike systems that formed immediately after the peak of the Ottawan orogeny (1070-1090 Ma), and possibly are more closely related to the Kensington suite than previously thought.

Jan 1, 2005

By C. E. Baltzer, W. H. Harper

"This study has been developed to illustrate the trend and pattern of distribution applying to the quantities and costs of the fossil fuels used, and the related amounts of electricity generated, in the thermal segment of the Canadian electric utility industry.Traditionally, Canada's requirements for electric energy have been preponderantly met by hydraulic power. The need for augmented supplies of thermally generated power has mainly developed since the close of World War Il-in an era that has seen drastic decline in the production of indigenous coal and buoyant expansion in the supply of oil and natural gas. Although coal currently is faced with serious competition from the fluid fuels, the utility industry in particular promises an advancing market for coal, because of its abundant resource, at prices less likely to show sharp increase. For Canada as a whole, this trend has been progressive since 1959, and, unbelievable as it may now seem, the extent of the advance by 1975, particularly in Ontario and the Prairie Provinces, may well be as much, or even more, than the present rate of consumption for all purposes.The text and the tables and charts are arranged to focus attention on: the growth of thermal genera ting capability; the historical trend in consumption of fuel and the related production of electricity; patterns of distribution by types of fuel and thermal capacity; the relationship of steam to other sources of thermal capacity; and the quantities, costs and related percentages of electricity generated by types and kinds of fuel used, both regionally and provincially."

Jan 1, 1966

By P. G. Hallof

The exploration staff of Campbell-Chibougamau Mines Limited has used past experience to delineate several areas of geologic interest under Lake. Chibougamau. Du• ring the winter of 1964-65, a reconnaissance induced polarization survey was carried out on the lake. First, several lines were surveyed over the known mu1.erahza-tion at the Henderson mine; the grid was then extended into the areas of interest. Several anomalous zones were located and drilled; one, of these proved to be of economic interest.

Jan 1, 1967

By Ashley Tews

In 2005, we automated a forklift-based Hot Metal Carrier to be capable of typical metal transfer operations around a smelter. The project was highly successful and the vehicle has demonstrated hundreds of hours of live autonomous operations to thousands of people from industry and the public. As a result of the exposure and success of the project, we have expanded its focus to demonstrate how various technology components can be utilised to gain benefits in other areas of industrial operations. These include asset tracking, vehicle usage analysis, pedestrian detection and infrastructure profiling. Each of these components was derived from the core autonomous vehicle technology suite and has shown a high potential for improving safety and efficiency of vehicle-related operations, and improved diagnostic processes for measuring deformations of bakes and furnaces. The autonomous vehicle project and its extended technologies are described in this paper.

Aug 1, 2013

By M. Mezbahul-Islam

Thermodynamic modeling of the Mg-Cu-Ni system is carried out as a part of multi component thermodynamic database for Mg alloys. This system is being modeled for the first time using the modified quasichemical model, which considers the presence of short range ordering in the liquid. The thermodynamic descriptions of the binaries Mg-Cu, Cu-Ni and Mg-Ni have been extrapolated to the ternary Mg-Cu-Ni system using Toop geometric model. The constructed database has been used to calculate and predict thermodynamic properties, isothermal sections and liquidus projections of the Mg¬Cu-Ni system, which showed very good consistency with the experimental data.

Jan 1, 2011

By Warren A. Sheaffer

THE chief uses for copper are as a conductor of electricity and as the chief component in brasses and bronzes. For such uses, the copper must be of very high purity. H the impurities are zinc, iron, lead, arsenic, or antimony, they can be removed to a great extent by fire-refining. H, however, gold, silver, nickel, or cobalt are present, electrolytic refining is necessary. Electrolytic refining must be preceded by fire-refining and hence all impure copper must be fire-refined. The electrolytic refining of copper is most efficiently carried on when the impurities in the anodes are at a minimum. Some of the impurities tend to deposit with the copper at the cathode, while others remain in solution, decreasing the conductivity of the electrolyte and thus increasing the voltage necessary for refining. Since these dissolved impurities must be removed by continuous purifications, the amount of impurity in the anode copper should be reduced by furnace refining to some predetermined limit. Anode furnace operation aims to reduce these impurities to a minimum beyond which the cost of further furnace refining would exceed that of removing the remaining small amounts of impurities from the electrolyte. The anodes should have a fine-grain internal structure because any pieces of metal becoming detached from the anode during the electrolytic refining are inconvenient to remove from the cells and may cause short-circuits. Impurities tend to disrupt such a structure and thus form zones of weakness during corrosion. When the impurities are reduced to a satisfactory mini-mum, the anode, due to having a fine-grain structure, will corrode uniformly over the entire surface area exposed to the electrolyte. Oxides of the impurities may be volatile, in which case they pass off as flue gases, or they may form viscous slags having a lower specific gravity than molten copper, thus permitting their removal by skimming. Some impurities can be oxidized by introducing air into the bath. Due to the large solubility of oxygen in molten copper, oxygen is distributed uniformly throughout the bath and thus comes into intimate contact with all impurities. The oxides which are insoluble in molten. copper are removed either as flue gases or as slag.

Jan 1, 1942