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By Osamu Inoue, Takashi Yamashita, Takashi Ikemoto

The expansion project in Naoshima smelter and refinery to meet enhancing recycling business of E-scrap was successfully completed in 2016 to have a capacity of 110,000 tpa of E-scrap treatment. Increasing treatment of E-scrap has raised the Ni content of copper anode to 4000 ppm on average, which is double the level of 10 years ago, and to 6000 ppm or more occasionally. The tank house has refined such copper anode to copper cathode with starter sheets. Since most Ni in Copper anode dissolves in copper electrolyte, the Ni content of the electrolyte has increased to 27 g/L and more. Ni accumulated in the electrolyte has increased power consumption during the electrolytic refining of copper, although cathode quality has been controlled satisfactory so far. In order to ensure sustainable operation while growing E- scrap business, the NiSO4 process has been expanded recently so as to recover Ni in the electrolyte more and the pressurized-leaching technology will be introduced to the slime leaching process so as to enhance the capacity of slime treatment and to improve Ni recovery in the near future. INTRODUCTION In recent years, the treatment amount of E-scrap at Naoshima smelter and refinery has increased according to the growth of its recycling business as shown in Figure 1, while impurities from E-scrap have concentrated in copper anode as well. Especially, Ni content in anode has been increasing remarkably since 2012, causing to raise Ni content in the electrolyte as shown in Figure 2. The increment of Ni content in copper anode and electrolyte has adversely affected the electrorefining process, slime leaching process, and NiSO4 crystallization process at the tank house. Such severe conditions provided opportunities to redesign the tank house to establish a robust process to which more Ni is acceptable.

Jan 1, 2019

By I. M. R. Duarte, J. A. Rodrigues-Carvalho, F. R. S. Rosa, A. B. Pinho

"This paper aims to contribute to the knowledge of the mechanical properties of the shales and greywackes which constitute the flysch-type deposits of the Baixo Alentejo Flysch Group, in the south of Portugal. These formations are flysch-type deposits constituted by sequences of usually thick greywacke beds alternating with thin shale beds, which include sometimes intercalations of conglomerate beds. All the sedimentation of these flysch formations was controlled by tectonics. At the same time, should have occurred along with the first Hercynian deformation phase, a low-grade metamorphic event (chlorite zone), that affected these flysch deposits. This study highlights the influence of anisotropy and heterogeneity of these flysch rocks on their physical and mechanical characteristics. The anisotropy verified in some physical properties and on mechanical properties, due to the foliation makes difficult the sample preparation for the laboratory tests. Besides, it induces a scattering of the properties values measured, as for example, the strength and the deformability. The heterogeneity is related to the main features of these geological formations, which are constituted mostly by thinly stratified greywackes and shale beds, which sometimes may affect the results of the laboratory tests making them less representative. The study is made by using both shales and greywackes that constitute these flysch-type deposits in order to evaluate their geotechnical properties, mainly of the shales. Samples of these two rock materials, are tested accordingly a laboratory testing programme, which includes which included mineralogical analysis (X-ray diffraction), physical tests (bulk density, porosity, and void index) and mechanical tests (uniaxial compression, and deformability tests). INTRODUCTIONOne of the factors that most influence the geomechanical behavior of rocks, as well as rock masses is the anisotropy. The word anisotropy comes from two Greek words ""anisos"" (meaning uneven) and ""tropos"" (meaning direction). A body or material is considered to be anisotropic, where the same property has different values depending in which direction it is measured, therefore, an anisotropic material is one whose magnitude of the properties depends on the direction in which these are studied or measured. Otherwise, it is about an isotropic material. However, the fully isotropic materials are quite rare in nature."

Jan 1, 2015

By Yan Jie

A series of production technologies are described for gold recovery from complex gold concentrate blended with copper concentrate treated in the SKS smelting process comprising: 1) Feed preparation and proportionate feeding of complex gold concentrate and copper concentrate; 2) SKS smelting gold recovery operation and process control technology developed based on reaction mechanism, process simulation and slag formation optimization study; 3) a dry-process quenching arsenic collection technology developed during de-bottlenecking severe restriction of SO3 in the off-gas on As collection system by suppressing and eliminating SO3 in off-gas as a result of optimizing SKS smelting process conditions and spraying caustic soda absorbent so as to reduce off-gas dew point temperature; 4) electrorefining of impure anodes; 5) technology for recovering such precious metals as Au, Ag, Pt, Pd, etc. from high-Sb copper anode slime produced as a result of gold recovery from complex gold concentrate by using SKS smelting process. INTRODUCTION Gold concentrate resources in China are mainly found in Shandong province, Henan province and the Inner Mongolia Autonomous Region, etc. Currently, recovery of gold is based on pre-oxidation (roasting) cyanide leaching process. This process produces a large amount of cyanide-containing wastewater, cyanide leaching residue and relatively high SO2-bearing flue gas during production, which can cause increasingly more serious environmental pollution issues. Besides, this process route suffers from a relatively low precious metals recovery (70–80%) found when treating refractory gold concentrate and carbon-bearing gold concentrate. These issues have severely restricted the development of the precious metals processing industry in China.

Jan 1, 2019

By Dillon. Patricia

Business Growth ?Coal ?Targeting 30 million tonnes by 2013 compared to 19 million tonnes produced in 2009 ?Expanding Energy Business unit (Oil Sands) ?Copper -Strong growth potential for existing operations and development projects ?New gold strategy recently launched ?New markets for zinc Need to retain existing and attract new employees to support growth Engaged Employee ?Has a positive attitude towards the organization and its values ?Is a person who is fully involved in, and enthusiastic about, his or her work Engaged employees are more likely to stay with the organization.

May 1, 2010

By Teresa Sikora

For over 40 years the Institute of Innovative Technology EMAG has specialized in the development of systems and equipment for laboratory and on-line monitoring of coal quality parameters, as well as the implementation of these systems and devices in mines and power stations. Some of these systems, based on advanced radiation detection techniques such as ?-ray backscattering (ALFA-06 and ALFA -06/T systems) or dual energy ?-ray transmission measurement (ALFA-06/2E ash meter), and also the ALFA-06/3E system applying microwave technology for the measurement of moisture, have had numerous applications in Poland. At present, over 100 systems and devices are used in Polish hard and brown coal mines. For over 10 years, EMAG has been specializing in the development of systems and devices, based on natural gamma measurement technology. An on-line ash meter, RODOS and RODOS Ex, based on measurement of natural gamma radioactivity of coal, has been developed and put into operation. This technique has been also used in developing the portable ash meter WALKER and laboratory analyzer GAMMA NATURA. The paper briefly presents features of the above-mentioned devices, their limits and their obtained accuracy, but in particular refers to the laboratory analyzer, GAMMA NATURA, as the first such device in the world, and presents the results of ash and moisture content measurement in hard, brown coals and potassium salts. The possible applications and advantages of the device in coal mines are discussed. The paper also presents the implementation results of the portable ash meter, WALKER, and the on-line ash meter, RODOS, that is used underground in coal mines.

Aug 1, 2013

By A. P. E. Dirige

The stability design of cemented backfills is normally conducted using conventional approaches. Analytical or numerical models, backed by trial-and-error methods, are the primary means used to describe or predict the support performance of backfills during mining. The stability of paste backfill free-standing faces is a major concern due to potential consequences to production, ore dilution and safety. Available analytical or mathematical models are developed based on assumptions of the failure modes that may occur when vertical fill faces are exposed during adjacent mining. Numerical modeling serves to provide an understanding of backfill strength and deformation behaviour. Such approaches offer inherent limitations and generally result in conservative designs. In this paper, centrifuge physical modeling was conducted not only for performance evaluation studies, including stability analysis, but to develop an understanding of the strength and deformation behaviour of paste backfill exposed faces when the adjacent ore zone is removed. The failure mode and mechanics of failure observed in the centrifuge model of a given prototype situation are discussed in detail. Centrifuge model results were compared to numerical modeling and it was concluded that a sliding block failure mechanism that resembles a circular slip appears to be the predominant failure mode.

Aug 1, 2013

By Robert Marchand

_ North-western Quebec _ Bousquet mining district _ 21 M oz mining camp _ 100,000 t/yr (400 t/d) _ Shrinkage : 52 % _ Longhole : 40% _ Development : 8% _ 5 days/week _ 120 employees _Discovered in 1936. _12 changes of ownership. _Exploration & development : 1987 _Commercial production : 1990 _Shaft deepening : 1995 _Internal shaft : 1999

Oct 1, 2001

By J. G. Schofield, C. G. Tan, R. J. Ord

"Most electric furnaces in the nickel and copper smelting industries are still fitted with conventional electrode holders which consist of water-cooled electrical contact clamps and a pressure ring. The water cooling exerts a significant cooling effect on the electrode column. The importance of controlling the temperature of the Soderberg electrode paste at the contact clamp area is examined, using in-plant experience and computer simulation of the paste melting and baking process. In addition to the effect of water-cooling, the effect of other variables, including the mantle air temperature, the electrode current, the furnace freeboard temperature and the electrode slipping rate are discussed. Ways in which the variable heating conditions in the paste melting zone can be controlled are outlined.IntroductionIn most non-ferrous electric smelting operations, the breakage of Soderberg electrodes is an infrequent, isolated occurrence. Occasionally, however, a rash of breakages may be experienced on a particular furnace for what appears to be no obvious reasons. The extent of the breaks may not exhibit a uniform pattern; sometimes the break may be less than half a metre above the electrode tip; at other times it may be at or just below the roof level. The latter type of break is, of course, the most dangerous since it is closest to the non-baked, weak portion of the electrode paste column. No matter where the breaks occur, they result in abnormal furnace power, charging and tapping conditions and loss of production while the new electrode section is slipped and baked. On a six-electrode furnace, breakage on one electrode has the immediate effect of reducing the total furnace power by one-third. On a three-electrode furnace, the effect is more drastic, one half of the power being lost."

Jan 1, 1995

By R. F. Tylecote

"The closure of the iron and steel making plant at Consett in Durham in 1980 marked the end of an era-a long era in the world's iron and steel making history. Iron had been smelted in the Tyne-Wear area of the United Kingdom since before the Roman period, but apart from evidence of smithing in the Roman period, the historical evidence for iron production on a large scale dates from the 14th century.The paper describes sites in the area that first worked the bloomery process and then, in the 16th century, as did most of Europe, graduated to the blast furnace process. The main emphasis is on the early introduction of coal to iron making at the end of the 18th century and the use of the steam engine to render integrated sites possible.IntroductionIron has been smelted in the Tyne-Wear area of the United Kingdom since before the Roman period, but apart from clear evidence of smithing in the Roman period, the historical evidence for iron production on a large scale dates from the 14th century. Like many other countries, the United Kingdom benefitted from the visits of foreign observers, such as Jars, Svedenstierna, de la Houliere and Dufrenoy, who left detailed records. In modern times, information gained from excavations of iron and steel making sites has supplemented the historical record.Natural ResourcesUp to the end of the 19th century, the industry was wholly dependent on its own resources. Iron ore, limestone, wood, coal and water power were all found a short distance away from the main valleys of the Tyne and Wear. The main sources of iron ore were the coal measures, with rider ores from the lead vein s in Alston and Weardale, and carbonate ores from shale horizons in the Carboniferous limestone. Good coking coal was available from West Durham and reasonable coal from the Tyne valley and Northumberland limestone. Limestone was plentiful."

Jan 1, 1983

Agenda ? Where?s Victor ? What work was done to get approval to spend $982m ? a brief history ? Some project facts ? The triple bottom-line accomplishments to date ? Construction A Brief History of Victor ? 1960?s ? first sampling in area ? 1980?s ? stream samples and Victor kimberlite discovered ? 1990?s ? test / bulk samples ? 1999 / 2000 ? large bulk samples ? 2000 / 2003 ? technical evaluation through to Feasibility Study, permitting process

May 1, 2006

By Dean Gerhardt

Why the need for proactive loose detection? ?? Past history of ground falls in Saskatchewan mines prompted research into new techniques for ground control. ?? Traditional tools for ground assessment (i.e. visual inspection, sounding with scaling bars) are not proactive and can often be time consuming. ?? Need existed for a system that was non-evasive, time efficient, and could be managed by a single operator. Ground Penetrating Radar (GPR) immerged showing the greatest potential.

May 1, 2008

By Mehmet F. Taner

"The East Sullivan Stock (ESS) is a small, composite felsic alkaline pluton of presumedlate Archean age in the Val d’Or mining district. Three main facies have been distinguished: mon-zonite sensu stricto, porphyritic monzonite, and green trachytic porphyry. This monzonitic group ofrocks is of relatively homogeneous composition with high abundances of Na2O, K2O, Ba, Sr, Rb, Zr,Mo and LREE. The alkaline ESS is distinguished from other igneous units in the Val d’Or miningdistrict, such as the Bourlamaque Batholith, by relatively high concentrations of Ba, Sr, Rb, Mo, Cuand Au. The ESS hosts many base (Cu, Mo) and precious (Au) metal occurrences, including: (1)porphyry style Cu-Au-Mo disseminated sulfde deposits, (2) Cu-Au deposits in volcanic rocks near the ESS contact, and (3) pyritic gold mineralization in east-west trending shear zones. The ESS is well defined by concentrical zoning on the aeromagnetic vertical gradient color map, and displays four linear trends, which are assumed to be structural lineaments, at 035°-055°, 320°-300°, east-west, and north-south. The main mineral occurrences related to the stock display a preferred spatial association with the east-west linear magnetic trends.The ESS is preferentially located along a major structure and was emplaced late in the evolutionof the Abitibi subprovince like other felsic alkaline plutons. This stock is similar to late-tectonic min-eralized felsic alkaline intrusions of the Kirkland Lake and Larder Lake mining districts in Ontario, and to the Allard stock in the U.S.A. which is associated with gold and base metal mineralization. Similarities also exist with younger alkaline plutons associated with Cu-Mo-Au porphyry deposits in the Canadian Cordillera, which formed in tensional tectonic environments. The felsic alkaline magmamay have formed by partial melting of deeply buried supracrustal rocks, concomitant with the development of deep fractures such as the Cadillac Fault. In such an environment, hydrothermal solutions carrying remobilized metals from deep supracrustal rocks may have deposited gold and base metals in structural traps. Plutons similar to the ESS should be good targets for mineral exploration. Copyright © 1996 Canadian Institute of Mining, Metallurgy and Petroleum."

Jan 1, 1996

By Xuanxue Mo, Kaihui Yang, Steven D. Scott

Abstract -The Changning-Menglian metallogenic belt in western Yunnan, China, is characterized by the occurrences of both Pb-Zn-Cu and Cu massive sulfides in Permo-Carboniferous mafic volcanic sequences. These deposits were formed in a back-arc basin at a rifted continental margin in the Paleozoic Tethys Ocean. Pb-Zn-Cu deposits are associated with alkalic basalt, andesite, and lesser felsic volcanic rocks intercalated with limestone, which probably formed along an immature rifting segment on a continental basement. These volcanic rocks are enriched in K, Ti, LREE, and other incompatible elements, and have the attributes of alkalic within-plate basalt. An extensive unit of sulfide- carbonate-silica shale in proximity to massive sulfides contains high values of Mn, As, Mo, W, Sn, Sb, and Hg, and has REE patterns that are similar to the volcanic rocks. This, together with the graded bedding in the footwall volcanic rocks, suggests that the sulfides precipitated in a shallow, unstable, and carbonate-saturated volcanic basin. A stringer zone is traced downward for 500 m below the massive sulfide orebodies. It is characterized by an upper sericite-quartz zone and an extensive lower skarn alteration with enhanced W, Sn, and Bi. Lead isotope data show both continental basement and magmatic sources may have supplied the ore metals. Cu deposit and occurrences are hosted by tholeiitic units that represent the mature spreading segments in the back-arc basin. The tholeiitic lavas have LREE-depleted or flat REE patterns similar to MORB or back-arc mafic lavas. The cupriferous massive sulfides are overlain by an extensive unit of chlorite-magnetite or ochre, suggesting a relatively oxygenated oceanic basin. Ni and less Co mineralization is found in dolomite veins of the stringer zone. Enhanced concentrations of Ni, Co, Au, and As are found in the massive sulfides and in sulfide-rich tuffites. The geological setting and mineralization of the Changning-Menglian belt has similarities with modern back-arc basins such as the Manus Basin in the western Pacific.

Jan 1, 1999

By K. A. Foxford, D. A. Polya, R. P. B. Hebblethwaite

"Abstract-A variety of techniques for interpreting systems of mineralized echelon veins is discussed using examples from Panasqueira and SW England. As aids for exploration and mine planning, and as a tool for ore reserve evaluation, particular emphasis is placed upon establishing vein morphology in the third dimension, and upon understanding vein dilation and propagation histories. Special attention is also placed upon investigating vein thickness and spacing relationships, and upon understanding vein segmentation. The relevant data for these techniques are all readily obtainable from stope and core sources.The vein systems described were produced in host-rock sequences that underwent incremental dilation in response to fluid overpressures, and individual veins display evidence for mineral infilling synchronous with their propagation. Echelon vein geometries resemble those reported from igneous dikes and sills: vein walls are stepped and veins are divided into segments arranged in echelons. Changes in vein geometry, from arrays to composite structures, reflect both the evolution of the vein system with time, and the changes occurring between the margins (arrays) and core (composite structures) of the system. These characteristic morphologies can be used to infer vein propagation and fluid injection trends, proximity of neighboring veins, and the shape of the system as a whole. The techniques are applicable to systems of echelon veins produced under tensile conditions in rocks where faults were absent at the time of vein formation, and where subsequent deformation has been minimal. Further work is required to assess the application to echelon vein systems formed within more complex tectonic regimes."

Jan 1, 1995

By Kyle Paulsen

The Cameco Key Lake mill began processing U-bearing waste rock from the McArthur River mine in 2000. This ore often contains elevated levels of calcium (>4% by mass), resulting in less than favourable conditions in parts of the Key Lake mill, yet still contains U3O8 at a concentration of about 0.3%. To recover the U3O8 and reject as much calcium as possible, modifications were made to the grinding circuit in late 2007 to include a gravity concentrator. The concentrator allows this mineralized waste to be processed separate from the regular blend material, rejecting calcium and concentrating U3O8, thus improving the operating conditions in areas such as SX. This will be presented in greater detail along with results and further work.

Aug 1, 2010

By J. A. Ressinger

"The purpose of this paper is to discuss some of the differences between various methods of excavating and loading as they relate to mining operations. The intent is not to provide ""pat"" answers, but instead to raise some questions and set forth some reasonable guidelines.Specifically, the paper deals with the differences and relative merits of power shovels versus rubber-tired front-end loaders - or, carrying this further, comparing what could be called ""stationary"" loading or excavating devices to ""mobile"" types."

Jan 1, 1972

By E. Dernedde

Industrial plants located in the province of Quebec, Canada, are subjected to large variations of the ambient air temperature, Building ventilation systems of these plants must have some flexibility in order to meet industrial hygiene standards (TLV for chemical substances, heat stress and cold stress) at any time of the year, The building ventilation of a bath treatment plant of an aluminium smelter in Quebec was examined under summer and winter conditions, Part of the plant has periodic emissions of hydrogen fluoride gas and heat from hot anode butts, CFD modeling was used to optimise the building ventilation of the bath treatment plant, The present study proposes a modified building ventilation system, which improves the internal environment, complies with industrial hygiene standards and also reduces heating costs by 20 % during winter.

Jan 1, 2005

By P. Diehl, M. David

"As shortage in the supply of mineral commodities become more probable, there is an increasing need for reliable and comparable reserve/resource data. It is therefore necessary to standardize the traditional classification procedure by quantifying the three basic criteria in resource evaluation: economic feasibility, geologic assurance and recovery. For the portion of fairly well documented deposits and as far as their geologic parameters are concerned, geostatistical methods can considerably improve the quality of ore classification. In respect of economic feasibility and recovery, approved geostatistical methods can be introduced directly into the classification procedure. The concept of geologic assurance, however, requires a new interpretation in terms of geostatistical error spread. As the ""risk"" in estimating an ore parameter is also a function of the respective block size, it is reasonable to define not only upper limits for the risk intervals for each class of uncertainty, but also block dimensions which reflect the typical stage of planning associated with the different ore categories. An algorithm has been developed to block out areas inside a mine or a large panel which satisfies the constraints of an ore category in respect of the risk intervals of a parameter and in respect of their size. The method has been computerized and is demonstrated on a massive copper-nickel deposit.IntroductionFacing an uncertain future with respect to the demand and supply of mineral commodities, both governmental authorities and the mining industries show an increasing interest in a useful framework for the assessment and classification of the remaining mineral resources"". This is reflected by the recently published appraisal and classification scheme of the United Nations as well as by the new or revised classification systems of the USA; Canada or Australia. Moreover there are various classification schemes which are currently discussed in major mining companies."

Jan 1, 1982

By Michael Chender

Emerging Equity Sources ? Larger IPOs ? China Inc. ? Other sovereign wealth funds ? New funds and higher allocations ? Private equity

May 1, 2010

By D. Bai, F. Hamad, S. Abraham

For the integrity of welded structures such as pipelines, the toughness of the heat-affected zones (HAZ) is an important property. This property is often specified in terms of Charpy V-notch (CVN) impact toughness and determined by the standard test method. An experimental study has been conducted in an industrial laboratory to measure the impact toughness of the coarse grain heat-affected zones (CGHAZ) of an X80 line pipe material. The field girth welding conditions in terms of heat input were simulated, together with special edge preparation to improve the targeted testing of the CGHAZ. The effect of toughness of the neighboring regions, in particular the weld metal, on measured impact toughness of the CGHAZ was investigated. The fracture paths of the CVN tested samples were examined by both optical and scanning electron microscopy. The deviation of segments of the fracture path into the weld metal was found to have a significant effect on the measured impact toughness of the CGHAZ.

Jan 1, 2005