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By Real Daigneault, François Robert, J. Paul Golightly, Jean-Yves Cloutier, Jayanta Guha, Pierre Pilote

"The Casa-Berardi East, Center and West deposits, located in the Archean Abitibi, Sub province, are hosted by volcanic and sedimentary units of varying compositions, less than300 m from the Casa-Berardi fault (CBF). The CBF, a brittle structure, represents an increment in the structural evolution of a regional-scale deformation zone showing ductile-brittle behavior known as the Casa-Berardi deformation zone (CBDZ). The CBDZ is characterized by a mylonitic Sc1 foliation which is folded a.n4 deformed by a later sczfoliation in high strain zones.Four generations of quartz vein and fracture systems have been recognized within the Casa-Berardi deposits. Most economic gold mineralization, occurring in the second generation system, is found within high strain zones. This system hosts three types of mineralized structures: (1) banded quartz veins; (2) swarms of veins and mineralized host rocks; and (3) disseminated sulphides along fractures. An early carbonate hydrothermal alteration zone (pre- to syntectonic) surrounds the deposits. Alteration associated with gold mineralization is contemporaneous to late ( syn- to post-tectonic) relative to the development of progressive deformation in the CBDZ. The geological characteristics and paragenesis of the four quartz vein and fracture systems developed as an integral part of the geodynamic evolution of the Casa-Berardi deformation zone."

Jan 1, 1990

By J. B. Hadaway

The operation at Phu Kham commenced design and construction in early 2006 and was commissioned in May 2008. This paper will examine and discuss the project from the inception of flow sheet development and equipment selection, equipment design and manufacture, construction, commissioning and ramp up to full production. The paper will touch on the strategies employed to achieve a short schedule and the efficient use of capital, but with the main emphasis on the grinding circuit. Various challenges during the early years of operation will be discussed including the effect of ore characteristics, including competency, on the performance of the grinding circuit. Actions to overcome these challenges and to enhance performance will also be discussed. Finally, current and future plans to improve the performance of the grinding circuit and the overall plant will be summarised.

Jan 1, 2012

By G. Morin, F. Chiesa, B. Duchesne

The Quality index is a useful tool allowing to assess the metallurgical quality of aluminium AlSiMg foundry alloys (A356/357). Its value is calculated from the ultimate tensile strength and elongation; it increases with the metallurgical quality of the casting, i.e. with finer dendrites, lower microporosity and inclusion count and lower iron content. This Quality index does not depend on the degree of temper applied during the heat treatment (aging time and temperature). After defining the Quality index, it will be explained how it can be predicted from the knowledge of the local solidification conditions obtained from modelling. The paper will then present four case studies of castings for which the prediction of the Quality index by modelling was made. These case studies from different authors will involve the three most common casting processes used for producing high integrity aluminium castings, namely: sand casting, permanent mould casting and investment casting (lost wax). In all cases, the accuracy of the prediction will be assessed by comparing the predicted Quality index distributions to the experimental values based on the published measured values of the local tensile properties.

Jan 1, 2006

The Carboniferous sedimentary rocks of southwestern Newfoundland merit investigation because of petroleum, salt and gypsum possibilities and indications of base metallization along the equivalent of the Horton-Windsor con-tact. In this paper, Lower Mississippian (Anguille) strata are divided into three formations: (1) the Cape John below, (2) the Snakes Bight and (3) the Seacliffs. A correlation between these formations and the Craignish, Strathlorne and Ainslie formations of the Horton group? in western Cape Breton Island is suggested. The criteria for the Anguille subdivision are essentially lithological, but preliminary study of included spore assemblages suggests more precise interformational correlations between Anguille and Horton sequences. The re-measured lower portion of the type section of the Codroy group is presented to define more clearly the stratigraphic position of numerous gypsum and limestone beds. Because of rapid facies changes within the Codroy group a simplified two-fold division into upper and lower units is proposed on the grounds of

Jan 1, 1964

By T. Takayama Filho

Votorantim Metais Zinco is a smelting facility which produces SHG zinc, zinc alloys, sulfuric acid, liquid SO2, copper sulfate, cadmium metal and silver concentrate. It is located at Juiz de Fora, Minas Gerais State, Brazil. This facility has been operating since 1980 and its current capacity is 95,000 tonnes of zinc per year, using mostly imported sulfide concentrates.The plant uses the conventional roast-leach electrowinning (RLE) process, in which iron is removed from the circuit as jarosite. The residues generated by the RLE process, which amount to about 200 t/day (dry weight), were until 10 years ago, deposited in tailing ponds having no impervious lining. More recently, jarosite and other wastes have been deposited in a properly built reservoir, but this is reaching its maximum capacity. In order to decommission these disposal operations and to reclaim the sites in an environmentally acceptable manner, Votorantim Metais concluded in 2004 a rehabilitation project for the old tailings pond and prepared detailed plans for managing the current and future disposal of jarosite-bearing residues. This paper describes the procedure for removing iron from the hydrometallurgical circuit and discusses the past and current status of the residue disposal sites, as well as the future challenges related to the environmentally acceptable handling of iron residues.

Jan 1, 2006

By A. Ignatieff

"Excavation, the principal mining process, 'which hitherto has been based largely on the intuition and logic of mining men, is increasingly receiving the attention of engineers and scientists versed in rock mechanics. The paper intro-duce the principles of this science in simplified form, directed both to underground and open-pit mining. Reference is made to the large annual tonnage from ore and rock excavations, which in 1967 were responsible for 250 million tons of mineral production in Canada.The urge to transform excavation into a continuous instead of an interrupted process is discussed with references to the various types of energies employed or proposed in rock breakage or excavation. Due to the rapid decay of applied energy in the discontinuous and heterogeneous rock environment, large confined blasts proposed for in-situ mining do not give much expectation of success as yet. Raises and ventilating shafts are already bored in reasonably hard rock. Tunnelling machines will be used for drifting and cross-cutting in the future, but continuous mining machines of the cuttmg and shearing type are not 'around the corner' for stoping typical orebodies. On the other hand, bed mining, particularly of coal, has led the way in continuous mining, and Remotely Operated Long-wall Face (ROLF) experiments are progressing in an encouraging way. Some reflections on the mining environment in relation to the human element are made."

Jan 1, 1970

By Duanyou Li, Qing Xiao, Zhiwang Wang, Xiaoqing Gan

"Seepage is a major cause of earth-rockfill dam failure. Numerical simulation of infiltration process, distribution of drift, flow velocity and direction after the impoundment can guide seepage control and evaluate its effects. A double field coupling model is established based on soil consolidation theory and the interaction between the seepage field and the temperature field. The simulation is implemented under the situation of core wall setted, core wall not setted, and core wall setted with concentrated leakage. The results indicated that the saturation line height was significantly reduced due to impervious core wall, and the temperature distribution is uniform above the saturation line. If concentrated leakage occurs, temperature distribution of dam was significantly changed, which is consistent with theoretical inference.INTRODUCTIONEngineering seepage field distribution must be calculated in seepage control design, optimization, and correction of new engineering construction of earth dams, as well as in seepage monitoring and evaluation of existing earth-rockfill dams. The aim of calculation is to identify the important parameters in seepage field, such as the coefficient of permeability, seepage flow, pressure, head, and allowable seepage slope, for effectively implementing seepage control design, correction, safety assessment, and anti-seepage reinforcement. These seepage parameters usually can be obtained by in-situ test and back-analysis based on reliable monitoring data.In order to obtain reliable monitoring data and reflect the earth-rockfill dam seepage state and change process, appropriate monitoring technology and monitoring method is necessary. The traditional seepage monitoring method is through site inspection and sensors (e.g., osmometer, piezometric tube and measuring weir) that buried in the structure and its foundation. However, there are still some disadvantages:"

Jan 1, 2015

By R. P. Chapman

The geochemical interpretation of results of statistical analysis of published multi-element stream sediment data from southwest and northern New Brunswick is presented. Element concentrations in southwest New Brunswick are low and comparable to element concentrations in background areas in northern New Brunswick. Deposits of copper and nickel are indicated in southwest New Brunswick. Anomalous element concentrations occur in several areas in northern New Brunswick and the elements most commonly associated with these anomalies are Cu, Pb, Zn, As and Ag; and also Mo, Wand Sb. Bedrock geology greatly influences element concentrations and may cause false anomalies. Manganese has a pronounced effect on the dispersion patterns of Co and also Zn, Mo, Pb, As, Ba and Ni. Nickel and Cr are strongly sympathetically related and this association is independent of bedrock type.

Jan 1, 1977

By J. R. Donald, K. Scholey

"Nickel has been mined and processed from the Sudbury basin for over 100 years. During this period, the process has evolved into what is one of the largest and most complex mining and metallurgical facilities in the world. This paper will describe the geology and mining of the Sudbury basin as well as the Copper Cliff metallurgical flowsheet circa 2005, including:•,Clarabelle Mill,•,The flash smelting furnaces,•,The bulk converters,•,Matte casting, separation, and processing•,The carbonyl refineries•,Carbonyl residue processing•,Copper processing•,Sulphur productsThe challenges of today and the opportunities for the future are discussed."

Jan 1, 2005

By Adrian Dance

The Antamina orebody is a geologically complex, polymetallic skarn located in the Peruvian Andes. A range of copper and copper-zinc ores are campaigned separately through the concentrator producing copper and zinc concentrates as well as lead and molybdenum by-products. Ore type classification at Antamina is based on chemical assays; geological or lithological variations are not considered. Consequently, each ore type demonstrates a wide range of concentrator performance. Antamina is currently implementing a system to track ore movements from the shovel face to the concentrator. Relatively sophisticated models of the ROM and coarse ore stockpiles ahead of the mill will be used to account for the variable delay between mining and milling. One of the numerous benefits of ore tracking is the ability to directly associate the measured concentrator performance with a physical location in the orebody. Using existing mine planning software, three-dimensional models can be created of such performance measures as metal recovery, concentrate quality, operating cost and reagent consumption. Such a database of information allows the true value of different ore sources to be determined. The value of an ore source is conventionally measured as metal content (individual or combined ?equivalent?) with a cut-off grade applied to indicate some base level operating cost. However, the true value of an ore source should include dynamic factors like haulage cost, reagent use, smelter penalties and even prevailing metal prices. If an ore source is considered from all perspectives rather than simply its potential to deliver value, the concept of ?ore? becomes more flexible. Any ore source that reveals itself to be unprofitable can be eliminated from the mine plan or possibly blended with others to improve its value. The ability to predict mill performance ? and thereby profitability ? is a powerful tool. In an operation such as Antamina, where managing ore sources, campaigns and the delivery of a variety of concentrates in a narrow timeline to customers is a daily challenge, prediction is the key to success and improved efficiency.

May 1, 2003

By H. J. McQueen

Mineral and energy resource consumption were continuously reduced by process improvements as chemical understanding was developed and applied. During the past two centuries, technological improvements increased human productivity that was accompanied by social advances and labour saving products; however, these sometimes proliferated to endanger sustainability, e.g., automobiles. In the steel industry, precisely controlled rolling of HSLA steels required little extra mineral consumption but reduced weight and heat-treating energy. Continuous casting of slabs reduced scrap compared to ingots and energy for the homogenizing soaking pit. Al alloy extrusions were improved by retaining the strengthening in the near-surface substructure, of high strength textures and of press quenching that is suitable for direct age hardening. Continuous bar casting of Al-0.65Fe, coupled with rod rolling and followed by wire drawing with only a final recovery anneal, yielded electrical wiring for households to replace less plentiful Cu and later for light-weighting use in autos and aircraft Looking backwards, the 1970 decade saw the first oil crisis and inspired Ottawa to undertake a campaign to develop an energy strategy that would decrease dependence on imported fuels. One significant undertaking under Energy Mines and Resources was the organization of industrial energy conservation, managed by each industry association,that collected detailed current statistics and set the goals for a 2-year campaign. The metal producing industries, as compared by E.C.N. Perryman to about 7.2 exajoules (EJ) for the nation, consumed about 0.8 EJ, being about one third of all heavy industries. While manufacturing consumed 30.2% of total energy, it created 87.3% of total national dollar value. Within the industrial envelope, smelting and refining utilized 28% (0.67 EJ, mining beneficiation 6.7%, 0.16 EJ); there was a significant contribution to exports: 80% of iron ore and 70% of aluminium in 1973. A general concern was that decreases in ore grade would lead to a rise in energy expenditures countering benefits from processing efficiency.

Jan 1, 2012

By Chi Zhang, Junyi Wu

"The use of permanent stainless steel cathodes for electrorefining and electrowinning of cathode copper had been introduced to the market long time ago and now is a well-accepted technology worldwide. During the last decades, the Chinese copper refinery industry had been growing rapidly and many large scaled production plants had been built. In the modern refineries, permanent stainless steel cathodes are introduced and used instead of traditional starter sheets. The most common steel grade used is austenitic stainless steel S31603 (316L/1.4404), while both S30403 (304L/1.4404) and N08904 (904L/1.4539) have been used depending on the actual working conditions, especially with regarding corrosion environment. While 316L permanent cathode functions well in many plants, different kind of problems, such corrosion and deformation, have been reported. There is therefore an increased need for more suitable material. New stainless steels, such as duplex stainless steels, with better properties have been tried and introduced into the application of permanent stainless steel cathode with satisfied results. The article introduces first the Chinese copper refinery industry and properties of duplex stainless steel in general, and then describes the development of using permanent duplex stainless steel cathode, including the actual working conditions, production of cathode sheets as well as the experiences of application in details. After more than one year’s usage, the advantages of permanent duplex stainless steel cathodes are clear seen.INTRODUCTIONChina has become a major player in the international copper market, accounting for around 40 percent of global refined copper demand. Despite the slowdown of the Chinese economy, the consumption of copper products will still increase, but with a medium and/or low growth which will be the new situation for the coming years. The average growth rate is expected to be around 5 percent per annual. In the coming Five-Year plan for National Economic and Social Development a number of initiatives will be finalized which will require massive amounts of copper. In 2015, the expected consumption of copper products will be over 9 million metric tons. The main driver of the consumption is the electric power industry which accounts nearly the half of the total consumption; followed by cooling application with 15% and transportation with nearly 10%, see figure 1."

Jan 1, 2016

By R. Simard

"Conventional exploration strategies identify many mineral deposits as potentially interesting, although only a few of them turn out to be of economic importance. In the context of exploration for sulphide nickel deposits in the Canadian Shield, a decisional model, based on a statistical study of parameters relative to nickel deposits as well as to barren sulphide occurences, has been developed.Because such geophysical variables as gravimetry, aeromagnetism and topography could be related to the relative importance of nickel-bearing deposits, a statistical analysis of 13 such variables was carried out for 98 targets which were considered promising after conventional exploration. Among these 98 targets are36 sulphide nickel deposits in the Canadian Shield and 62 drill-tested non-economic occurrences. The results of this study led to the development of a linear logistic model that permits evaluation, for each of the targets, of the probability of finding a nickel deposit of potential commercial interest. This decisional model can thus complement conventional exploration strategies.RésuméLes stratégies conventionnelles d'exploration définissent un très grand nombre de cibles comportant un inténet minier potentiel dont seules quelques-unes correspondent à des gisements économiquement importants. Dans Ie cadre de l'exploration des dépôts nickélifères du Bouclier Canadien, nous avons défini un modelé de décision fonde sur l'étude statistique de divers paramètres relatifs tant aux gisements d'importance qu'aux cibles dites stériles.Ayant fait l'hypothèse que certaines variables géophysiques (gravimétrie, aéromagnétisme et topographie) peuvent suffire à fournir des indications sur l'importance relative d'un gisement nickélifère, nous avons entrepris l'analyse statistique de 13 variables évaluées sur un échantillon de 98 cibles considérées comme potentiellement intéressantes par les stratégies conventionnelles d'exploration. Ces 98 cibles se composent de 36 dépôt nickélifères d ‘importance recontrés sur tout Ie Bouclier Canadien et de 62 cibles stériles reconnues par forage. Nous avons défini à l'aide de ces données un modèle logistique linéaire. Ce dernier nous permet d'évaluer pour chacune des cibles les chances de trouver un gisement. Ce modèle de décision peut done s'inscrire comme outil complémentaire aux stratégies conventionnelles d ‘exploration."

Jan 1, 1980

By Dao Dac Tao

The Vietnam coal industry in recent years has achieved the rapid growth. However, in the process of industrialization and modernization of the country, the demand for coal for energy is constantly increasing. This paper presents the Vietnam coal industry in the last stage: the opportunities and challenges facing the coal industry as it strives to become modern, highly effective and capable of meeting the demands of national energy security, all in harmony with socio-economic and environmental needs.

Aug 1, 2013

By M. O. Makwarela, M. W. Erwee, K. Bisaka

"Energy efficiency in mining and minerals processing forms part of Mintek’s long-term research strategy which includes a specific programme designed at overcoming the challenges faced by the South African pyrometallurgy industry.The electric smelting industry is currently severely constrained by the global economic downturn as well as by the availability and increasing cost of electricity. Efficient utilisation of electricity through energy recovery systems and improved smelting process flowsheets can significantly contribute towards creating sustainable operations.Apart from efficient engineering design and solid process control, smelting of either cold or hot pre-reduced ores has been shown to decrease furnace electricity consumption by more than 40%. Various methods of solid-state reduction tests have been carried out at Mintek in order to select the most appropriate process option in the context of the South African industry. This paper summarises a subset of the results obtained, specifically on pre-reduction tests done on South African chromite and manganese ore pellets.In this set of tests, it was found that the use of an organic binder, together with B2O3 as flux, promotes manganese ore pre-reduction, but retards the pre-reduction of chromite. By pre-reducing the manganese ore feed, significant cost savings can be achieved in subsequent smelting processes and there is potential to minimise manganese losses as a result of fuming, due to possible lower operating temperatures."

Jan 1, 2016

By W. Hardtke, B. Perry

Model reconciliation problems at the low-grade, high-nugget Phoenix gold-copper deposit led to an examination of the influence of production decisions on ore-waste classification. A conditional simulation study of the deposit was used as the basis for: 1) quantification of dilution at different bench heights, 2) quantification of ore-waste misclassification relative to bench heights and cut-off wades, and 3) determination of an appropriate number of samples to optimize ore-control polygon definition. Actual reconciliation data were empirically used to support conclusions. Simulations of both gold and copper were combined through net revenue modelling. These simulations increased understanding of the nature of the deposit and provided insight for resource modeling and mine planning.

Jan 1, 2011

By Roy T. Bowles

This paper focusses on technological developments which occurred in the village of Deloro, Ontario between 1868 and 1919. These developments illustrate the manner in which improved metallurgical processes linked Ontario mineral resources to industrial expansion. Overview of Deloro The village of Deloro is in Hastings county, about 5 miles from the village of Marmora, the site of the old Marmora iron works and the more recent Marmoraton iron mine. In this area, the Canadian Shield meets the Great Lakes lowlands. The first settlement in the vicinity occurred in the 1820s and was associated with the Marmora iron works. Settlement grew around agriculture. Gold was discovered in Hastings county in 1868. Deloro - the name derives from gold - developed as a concentrated settlement in proximity to several gold mines and the related processing activities. By 1901, substantial smelting works were successfully producing gold and arsenic from local ores. The village was developing as a company town within the framework of benevolent paternalism. For reasons associated with markets and with local ore supplies, the Deloro mills were idle for a period beginning in 1902. Developments in later periods connected Deloro to world events. In 1903, silver was discovered at Cobalt, Ontario. By 1907, M.J. O'Brien, who owned mines at Cobalt, had purchased the Deloro works and was using them to process Cobalt-area ores*.

Jan 1, 1999

In most instances, the preferred mining methods in steeply dipping narrow vein deposits are selective methods such as cut and fill or shrinkage. The main advantage of these methods lies in the higher degree of control over dilution that can be achieved. However, where ore body geometry lends itself to it, high yield bulk methods can also be attractive. Higher productivity (and the associated lower costs) and lower worker exposure are some of the significant advantages that have made such methods so popular. The Lapa gold mine located in North-Western Quebec uses the long hole mining method (with cemented rock fill) very successfully despite challenging ground conditions. This paper focuses on the experience of the mine with regards to drilling and blasting practices. Firstly, the reasons that prompted the selection of this mining method at Lapa are examined. Secondly, the challenges that the difficult ground conditions found at Lapa pose to drilling and blasting are discussed. Finally, the results of trials of different drilling and blasting strategies that were performed at the mine are presented with particular emphasis on the lessons learned.

Aug 1, 2013

By Robert D. McKellar, Luke Frawley, Okrasa. Richard

"The resource industries in Canada are facing increasing global competition and stringent environmental regulations. This has made it essential for companies to lower operating costs wherever possible. Electrical energy rep-resents one variable cost that may be better managed and utilized, providing the user with lower operating costs, improved productivity and better yields.The utility industry is also facing changes in the way it must do business. Utilities in North America are facing the prospect of deregulation that will eliminate the monopoly they have traditionally held. This will force them to strive for lower operating costs, to maintain a competitive position and to improve customer ser-vice so as to maintain their customer base.Ontario Hydro has been working with industry for several years. Many opportunities for cost savings have been identified involving energy efficiency, process improvements and the use of new electro technologies. One useful service that the utility can offer industry is to increase the awareness of potential opportunities suited to their operations. This paper will provide an overview of some of the projects that have been implemented and those that are presently being evaluated. An electronic data-base of electro technology applications that is under development will also be described."

Jan 1, 1996

By X. Cao, H. Huang, Z. Dai

"Crystal phase of copper-containing slag regulation by the slag viscosity, cooling speed and cooling method, where the slag viscosity is related to the temperature and alkalinity. According to the mineralogy properties of a copper-containing slag, experiments of crystal phase regulation and flotation were conducted. When the copper-containing slag that adding a small amount of calcium oxide was cooled slowly at a rate of 3°C/min and about 1050°C n a cinder inclusion system, the viscosity of slag can be remained under 0.25 Pa·S and more than ??% of copper particles that the grain size is larger than 20 ?m in slag. The whole flow of flotation experiment was carried out to recover copper from the copper-containing slag with crystal phase regulating and the copper concentrate grade was ?????%, the recovery efficiency of copper was 94.18%.INTRODUCTIONChina's annual output of copper slag is more than 6 million tons, the current total has reached 80 million tons. It is equivalent to 640 thousand tons of copper metal with the copper grade of 0.82%. Most of the smelting slag were storage. It is not only occupy the land and pollute the environment, but also make a huge waste of resource (Alp, Deveci, & Süngün, 2008; Carranza, Iglesias, Mazuelos, Romero, & Forcat, 2009; Gorai, & Jana, 2003), therefore, it is good way to achieve copper slag resources by the effective recovery of valuable component from copper smelting slag, which is an important measure of the current process of copper smelting slag and implement the central authorities to vigorously develop the circular economy, improve the recycling of resources, increase copper production of intensive development (Zhou, et al., 1994; Zhang, Zhang, & Wang, 2005). Currently, researches on comprehensive utilization of the coppercontaining slag made a much progress (Wei, 2004; Liu, Gai, Yang, Sui, Li, & Fu, 2008; Liu & Zhu, 2008; Zhang, 2010; Sun, Chen, & Tang, 2012; Qin, Wang, Ren, Wei, Peng, & Gu, 2012). Flotation is one of the most effective method to recover the copper from smelting slag, which has the features of low cost and high efficiency (Song & Liu, 2001; Zhang, Wang, & Li, 2012). But the copper particles in the copper smelting slag distribution is very uneven, and the thickness of the material is very serious. The copper content in the micro level is higher, the size of copper sulfide ore is less than 0.043 mm, which leads to the difficulty of the monomer dissociation (Tossavainen, Engstrom, Yang, Menad, Lidstrom, Larsson, & Bjorkman, 2007; Moustakas, Mavropoulos, Katsou, Haralambous, & Loizidou, 2012). In this study, according the process mineralogy of a smelting copper slag, the crystal of smelting copper slag was optimized by controlling the temperature, alkalinity, cooling rate and cooling method, which makes the fine copper mineral particles in the copper slag crystal further, and can be used to meet the particle size requirements of flotation, thereby enhancing the flotation of copper."

Jan 1, 2016