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By Guery Augusto Echeverria Martínez

O profissional brasileiro tem uma grande capacidade em criar soluções. Na área de trefilação o resultado desta criatividade é facilmente encontrado em diversos pontos do processo. No entanto esta capacidade não segue um roteiro, simples ou complexo, de tal forma a possibilitar respostas inovativas em alto nível e por toda a equipe da organização. Este trabalho propõe o ensino da metodologia TRIZ e de ferramentas auxiliares a todos os colaboradores das trefilarias. A TRIZ é uma metodologia sistemática, isto é baseado em regras, o que permite a obtenção de uma solução direcionada, portanto, muito mais assertiva no processo de inovação. A natural criatividade do profissional brasileiro pode ser amplificada com o aprendizado de uma metodologia que sistematize o desenvolvimento de novas soluções para antigos e novos problemas no processo de trefilação. O aprendizado das ferramentas básicas de TRIZ, associado a outras ferramentas, podem tornar os profissionais da área de trefilação mais confiantes e efetivos na análise de problemas, geração de ideias e prevenção de falhas.

Aug 16, 2017

By George J. Conroy

Electrical power generation was studied in a laboratory-scale, open-cycle vortex MHD generator, which offers several advantages over straight-channel generators that require separate combustors. Compactness, lower capital cost, and high-energy release are obtained by combining the combustor and generator into one unit in the vortex generator. In addition, the vortex generator uses a simple solenoid rather than the more complex and expensive saddle magnet required for straight channel generators. Although the vortex generator must utilize combustion gases with a low Hall coefficient in order to be efficient in direct comparison to the linear generator, the primary motivation for this experimental device in terms of ultimate objective was to investigate the vortex generator with applications to direct coal firing and with combustion taking place in specially designed expansion nozzles. The vortex device offers one decided advantage over the linear device in this regard because slag deposits do not degrade or short-circuit the coaxial electrodes as is the case for a linear machine. The experimental vortex generator consists of a modified cyclone burner 7 ½ in ID by 21 in long, with the inner wall used as one electrode together with a coaxial center electrode. Power was obtained by impressing an axial field of 3,000 G from an air core solenoid magnet. Tests were conducted by seeding natural gas seeded with potassium acetate and burning with preheated oxygen-enriched air. Power generation was lower than calculated because theoretical plasma velocities were not achieved.

Jan 1, 1972

By C. L. Dake

AN insistent and steadily growing demand is evident for the broadening of undergraduate curricula in engineering. Among suggested additions are training in public speaking, report writing, business law and contracts, accounting, finance, money and banking, scientific management, economics, social and labor problems, psychology, and ethics. The demand for these subjects comes from the older engineers and from the industries that employ our graduates. Of course, many of the men who suggest such changes are influenced largely by their personal needs and contacts, but the demand is sufficiently widespread to merit serious study by educators. In fact, many educators themselves concur in the proposals for broader training. These matters were examined intensively a few years ago in an exhaustive study of engineering education. Opinion at that time was rather strongly against any profound change. Since then, however, the whole economic system has undergone violent disruption. Even if recommendations made a few years ago were appropriate to the conditions then- obtaining, the enormously changed conditions of the present make advisable a further careful study of this problem. In recent years, mergers, to reduce costs, have sharply limited the number of engineers employed and have thereby intensified the struggle to secure positions. In this stiffer competition, engineers with the most adequate training undoubtedly fare the best.

Jan 1, 1934

By K. Drescher

Excavations in deep level hard rock mines show rheological or time-dependent deformation responses to mining-induced stresses. These are generally not as dramatic as those seen in soft rock environments, such as potash and salt mines, but these deformations can nevertheless become substantial in time. It is usual to see total excavation closure at a much earlier stage than predicted by numerical models, and real-time measurements underground have confirmed that closure takes place on a more-or-less continuous basis, with highest closure rates observed after a blast and then slowly diminishing with passing time. This paper describes laboratory tests to determine the time-dependent response of hard rocks to loading, the results of the tests, and then quantifies these effects to explain the time-dependent phenomena observed underground. The primary intention of this work is to help explain the various time-dependent deformation processes around typical deep level hard rock tabular excavations. Three mechanisms were investigated in two typical hard rock types present in the deep level gold mines in South Africa, namely Ventersdorp Lava and Elsburg Quartzite. Uniaxial compression creep studies were done as the first part of the study followed by shear creep studies on discontinuities where crushed lava and crushed quartzite as well as a natural gouge were used as infilling. The last part of the study consisted of triaxial post-failure relaxation tests. The compression creep tests and the triaxial post-failure relaxation tests showed that the amount of energy dissipated by the lava is significantly less than for quartzite. For mines operating at depths greater than 2000 m the implication is that the lava must show a greater rockburst-proneness than the quartzite. Since the lava shows a lower post-failure stress relaxation, it can store sufficient energy for multiple rockbursts, which is seen in the clustering of multiple seismic events in the deep level mines. This study provides the first data available for energy change calculations in fractured rock masses, and provides the first general indications for rockburst intensities ahead of active mining faces.

Jan 1, 2003

By John D. Spencer

Clean energy production from coal, oil, and gas, and the development of these and other energy sources continued to be a major objective of the energy research program of the Bureau of Mines.3 In 1971 increased emphasis was placed on the production of fluid fuels and chemicals from coal. Advances were achieved in the development of the Synthane and Hydrane gasification processes for producing pipeline gas from coal (page 31), and progress was made in research on solid wastes utilization (page 2), and on liquid fuels production from coal (page 37); Coal mine safety, solid waste disposal and utilization, coal preparation and transport, and fundamental research on coal and related products also continued to be the subject of extensive research. Improved methods for extracting petroleum and natural gas without surface and subsurface pollution featured research on these vital fuel and energy sources. This research was highlighted by studies of the fracturing systems of reservoir rocks, including subsurface fracture mapping and new fracturing techniques to achieve optimum production of oil and gas (page 52). Of equal importance were projects on oil recovery by water or gas flooding (page 52), by steam injection (page 57), on the identification of oil spills (page 63), and on means to reduce vehicular exhaust emissions (page 66).

Jan 1, 1972

A Robust Chemically Enhanced Electrostatic Separation Technology Physical separation processes such as gravity, magnetic and electrostatic separations are extensively used in heavy minerals separations. Electrostatic (aka High-Tension) separation facilitated by the conductivity differences, in particular, is used for separating rutile from zircon. Although electrostatic separation is effective, it is not efficient. It suffers from separation efficacy issues owing to sensitive variables such as humidity, surface contamination, particle sizes and the temperature of the feed and other equipment parameters. The variations in the process conditions especially with humidity, temperature of the feed and the mineralogy and surface impurities can cause significant reduction in the separation resulting in production rate losses and product quality issues. Cytec Industries has developed chemical enhancement technologies for electrostatic separation for rutile -zircon separation from the heavy minerals. The major advantage of our technology is its higher separation efficacy in the first pass, substantial energy savings and most importantly its ability to do separation at room temperatures. The bolt-on nature to the existing electrostatic also an added feature that reduces the capital expenditure significantly. The separation efficiency between rutile and zircon was increased as much as 8 - 11 per cent compared to control. It is possible to extend the chemical enhancer technology to problematic feeds and other mineral systems that are not easily amenable to conventional electrostatic separation.

Sep 13, 2010

By L. A. Cramer

South African platinum mines produce the world?s majority of platinum metal that is used in autocatalysts and jewellery. As the platinum market is forecast to grow at healthy rates into the future, the South African producers, Anglo Platinum, Impala, Lonmin and Northam, are planning to expand in the next decade. Furthermore, a number of smaller producers who are accessing other mineral rights are entering the buoyant market. The South African platinum mines have traditionally exploited the Merensky Reef of the Bushveld Igneous Complex (BIC); however, the mining of this reef is reaching depths that require significant vertical shaft systems and costly refrigeration for access to the orebodies at deeper levels. In the past decade all of the producers have begun to mine the less attractive UG2 reef because of its cheaper mining costs. This UG2 reef contains significant quantities of chromite with typically a chrome-to-iron (Cr/Fe) ratio of 1.35. UG2 ores can contain between 10 and 25% Cr2O3dependingupon the reef width and the selected mining method. It is relatively cheap and easy to extract a portion of the chromite from a platinum concentrator tailings stream at a grade of between 40?42% Cr2O3. However, it is only in recent years that some ferrochrome producers have begun to source some of their chromite from the tailings of platinum producers. South Africa is also the world?s largest single producer of ferrochrome and supplies much of the world?s stainless steel producers and thus the growing market for their product. As the traditional sources of high Cr/Fe ratio ores have been depleted at the shallow economic depths and thus have become more expensive sources of chromite, technical developments have improved the ability to use fine chromite economically to make acceptable grades of ferrochrome. Thus UG2 fines are now becoming possible cheap sources of acceptable feed to the ferrochrome industry. The abundance of feedstock for ferrochrome production and the lessening dependence on mined material will impact upon the structure of the ferrochrome business in South Africa. With continued platinum mining from UG2 reefs, South Africa is set to remain highly competitive in the world?s ferrochrome/stainless steel industry.

Jan 1, 2004

By L. W. Brandt

The Bureau of Mines, as part of its mission to effect pollution abatement, conducted research to study various means of dewatering Florida phosphatic clay wastes and reclaiming mined lands. The work was done in cooperation with 10 Florida phosphate companies. During this work, a novel technique to effectively dewater phosphatic clay wastes was developed. The solids contained in the clay waste slurry are slowly compressed by moving wire mesh screens through the system. In a typical application, the screens were moved downward, compressing solids ahead of the screens. The rate of movement of the screens is an important variable in the process. It is believed that the moving screens distort the gel structure of the phosphatic clay system and cause the release of water. Samples of 18 clay wastes, including a high-grade attapulgite from beneficiation plants of the Florida phosphate field, were studied using the method. Typical samples were concentrated from initial solids of 4.7 and 11.9 percent to 16.8 and 25.2 percent, respectively, in 3-1/2 days. The high-grade attapulgite sample was dewatered from 2.7 percent solids to 13 percent solids in the same period.

Jan 1, 1980

By F. B. Samani, B. Stabel

The 1,000 MW Hydro Power Station Masjed-e-Soleiman (formerly called Godar-e-Landar) in Iran is under construction since 1992. The rock engineering aspects of the major underground structure, i.e. the powerhouse cavern shall be reported on in detail. The geotechnical investigations are described and results given. The results of several geotechnical analyses are presented. The designed and executed rock support is given. A description of the monitoring systems and typical measurement results obtained during and after excavation are presented. The lessons learnt during construction of the Stage-I powerhouse cavern were applied on the extension of the powerhouse cavern, which is to house an additional 1000 MW. Details regarding the unexpected behaviour of the Mudstones are given. Die 1000 MW Wasserkraftanlage Masjed-e-Soleiman (vormals Godar-e-Landar genannt) befindet sich seit 1992 in Bau. Dieser Artikel berichtet im Detail über die felsbaulichen Aspekte der Untertagebauwerke, insb. der Maschinenkaverne. Die geotechnischen Untersuchungen werden beschrieben und deren Ergebnisse wie die Ergebnisse verschiedener Berechnungen werden präsentiert. Die geplante und die ausgeführte Felssicherung wird angegeben. Die eingebauten Überwachungseinrichtungen werden beschrieben und typische Ergebnisse während des Aushubs und danach werden dargestellt. Die Erfahrungen beim Aushub der Kaverne der Stufe I wurden beim Entwurf der Kaverne der Erweiterungsstufe II, die weitere 1000 MW beherbergen wird, berücksichtigt. Details zum unerwarteten Verhalten des Schluff-/Tonsteins werden angegeben. La centrale hydroélectrique de Masjed-e-Soleiman (dénommée anciennement Godar-e-Landar), d’une puissance de 1.000 MW, est en construction depuis 1992. Un rapport détaillé sera présenté sur les aspects relatifs à la construction en enrochements de l’aménagement souterrain principal, à savoir la caverne abritant la salle des machines. Une description des investigations géotechniques réalisées y est fournie ainsi que les résultats correspondants. En outre sont présentés les résultats de plusieurs analyses géotechniques. L’ancrage dans la roche tel que projeté et réalisé est présenté. Une description des systèmes de contrôle ainsi que les résultats de mesures typiques obtenus au cours des travaux d’excavation sont donnés. Les leçons tirées lors de la construction de la Phase 1 de la caverne de la salle des machines furent appliquées à l’extension de la caverne de la salle des machines, qui doit abriter une unité supplémentaire d’une puissance de 1.000 MW. Par ailleurs, des détails sont donnés sur le comportement inattendu des argilites.

Jan 1, 2003

By Eduardo Cota

Graças à miniaturização e aumento na robustez de equipamentos eletrônicos, a robótica tem estendido as suas aplicações até às mais diversas áreas. Atualmente a mineração possui muitos desafios a serem resolvidos com soluções tecnológicas autônomas ou teleoperadas. Este trabalho aborda a descrição de algumas das técnicas e projetos do estado da arte da robótica que estão sendo aplicados em ambientes de mineração no Brasil e no mundo.

Oct 30, 2017

By M. Tangstad, B. Monsen, H. Midtgaard

The increased attention towards reducing emissions of fossil CO2 due to its potential global warming effect has resulted in a focus on renewable resources, as charcoal. Since charcoal is produced from growing wood it does not contribute to global warming. This paper gives a brief review of consequences of and reasons for using charcoal in the silicomanganese (SiMn) production. Results are presented from practical SiMn smelting experiments, on a pilot scale, using charcoal as reduction material and comparing with coke. As slag- and CO2-reactivity are important for furnace performance these features have also been measured.

Jan 1, 2004

By E Selvapandian, R Barr

Arrium (previously OneSteel) initiated a desktop study into the performance of its hematite ore beneficiation plant in early 2010. The beneficiation plant utilises jig concentrators and spirals to upgrade low-grade hematite recovered during mining at the Iron Duke (ID) mine site located 60 km south-west of Whyalla. The study, conducted in conjunction with Mineral Technologies, identified a number of opportunities for improvement, which were validated by a series of sampling campaigns and a pilot plant trial. One of the major recommendations was to upgrade the ultra-fines processing circuit from a single-stage spiral circuit to a three-stage circuit. The upgrade of the ultra-fines circuit was estimated to provide a significant increase in fines production and grade.In order to capitalise on the strong iron price at the time of the project, Arrium decided to utilise a fast-tracked approach to design, construct and commission the processing equipment required to achieve the improvements identified. This decision introduced the risk of missing critical steps in the project development process, which could have potentially resulted in major issues in latter stages of the project. In addition to the challenges introduced due to the expedited time line for project completion, this project presented unique challenges due to its brownfield nature. One such challenge faced was the integration of the new equipment and control system software.Furthermore, the importance of the ID ore beneficiation plant (OBP) contribution to the companyÆs export commitments meant the upgrade work had to occur while minimising disruption to normal operation. This decision presented a set of new challenges to an already complex project. One such challenge was the need to build and commission the new spiral circuit in isolation from the operating plant.The aim of this paper will be to highlight some of the challenges faced in a complex brownfield project such as the ID OBP upgrade and discuss how they were managed to enable the successful commissioning of the process in early 2012.CITATION:Selvapandian E and Barr, R, 2013. Managing challenges faced in the brownfield commissioning of an ultra-fine hematite processing circuit at ArriumÆs Iron Duke ore beneficiation plant, in Proceedings Iron Ore 2013 , pp 533-538 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By Shuvranshu K. Rout, Anup K. Mandal, Biswajit Das, Manos De

"To adopt new technology advancement in Steel Plant, there is a requirement of shifting of operation process from Coke Wet Quenching (CWQ) to Coke Dry Quenching (CDQ). New CDQ chamber foundation with deep basement and underground conveyor tunnel are to be constructed in an operating plant where heavy foundations and structures are located in close proximity. Furthermore, the existing CWQ system will be in operation during new underground construction and erection. Challenges to deep excavation of tunnel and chamber foundation consist of non-uniform ground condition, prevent washing out of soil from bottom of existing foundations, stability of existing nearby structures, presence of large number of underground utilities, ensuring safe underground workplace to construction resources engaged in new construction work along with project schedule and budget constraints. A combination methods involving use of soil nailing, soil grouting, contiguous bored pile and micro pile had been adopted for protection of excavation sides as well as existing structures. Each side of excavation in different stretches were analysed during design as well as construction stages. The use of combination of all techniques in a single brown field project in context of the nature of site constraints and safety issues made this a unique project.INTRODUCTIONSteel Industry is one of the backbones of industrial growth of any developing country like India. Due to increasing land prices most of the steel plants in India are expanding within their existing plant facilities. In addition to that, there is demand of adoption of new technology for future expansion projects to set new benchmarks with global standards.The property owner had earlier installed a Coke Wet Quenching (CWQ) for their Coke Plant. Now, there is a requirement from process department to proceed with Coke Dry Quenching (CDQ). To facilitate the CDQ within the existing CWQ which will be in operation is the main challenge for the property owner. The second challenge is the limited space for underground construction and subsequent equipment erection within the stipulated time frame.From a geotechnical prospective, the project team had uncertainty and reservations in their mind about the construction methodology. Therefore, the role of three “C”: ‘Consultant’-‘Client’- ‘Contractor’ and their combining brainstorming is essential to freeze a working plan for achieving the goal. In this paper, only the excavation support systems for underground foundation structures have been highlighted in the context of solving geotechnical problems."

Jan 1, 2017

By J. J. Bezuidenhout

The waste-heat boiler is used within the Sulphide flash smelting process as the main dust and energy recovery unit. The large volume of off-gas discharged from the flash smelter is at a very high temperature (1350°C) and contains a significant dust load that subjects the downstream waste-heat boiler to tough and demanding conditions. The boiler cavity is especially prone to dust accretions, fouling, and corrosion caused by accumulation of molten particles and precipitation of sulphuric acid. Computational fluid dynamics (CFD) is applied within a qualitative study to model the flow and heat transfer distribution throughout the waste-heat boiler. The commercial CFD package, Fluent 6.2.16, was applied to a modified waste-heat boiler (23 m ×11 m ×5.4 m) within the Outokumpu flash smelting process. This investigation focuses on the geometric modifications to the typical boiler design, which includes elevation of the ceiling, placement of flow-obstructing baffles and radiation plates parallel within the flow path. Also investigated were various boiler operating conditions such as the circulation of process off-gas, air leakage from the dust discharging hoppers and variation in inlet gas composition. The geometric modifications had the desired effect of increasing the volumetric utilization and therefore enhancing heat transfer between the boiler surface and the gas stream and dust segregation. Introducing circulated off-gas at a rate of 20 m/s and at a 45° angle to the front of the waste boiler further enhanced cooling while reducing the high impact of the furnace-uptake gas-stream on the boiler ceiling. The placement of radiation plates was found to be very effective in enhancing the heat transfer surface and distributing gas flow within the boiler. These results present recommendations towards an improved waste-heat boiler design. Keywords: flash smelting, waste-heat boiler, CFD simulation, off-gas cooling.

Jan 1, 2008

By Raja V. Ramani

The potential usefulnuss of reclaimed surface-mined land has received much attention in recent times. This attention is partially due to the establishment of federal environmental reclamation standards but concern for achieving better land uses has also been shown by interested members of the mining industry. In an effort to develop a procedure for evaluating postmining land use potentials, specific mines in various regions of the U. S. were studied to determine the extent of current mined-land planning and to discover characteristics that are regional in nature. As part of this investigation, a 430-acre surface mine in Clear-field County, Pennsylvania has been studied. Established site planning principles have been applied to the case study site including formation of a data base, development of alternate land use plans, and evaluation of the economic, environmental, and social impacts of the land use alternatives. Key factors affecting site realization have been identified along with positive suggestions for applying land use planning processes to mined-land planning.

Jan 1, 1983

By Cristhian Carrión

El trabajo evalúa la aplicación de la Inteligencia Artificial (IA) o Redes Neuronales Artificiales (RNA) en el procesamiento de minerales, con el fin de predecir y optimizar recuperaciones. El estudio describe el trabajo con variables diversas, el modelo de entrenamiento y aprendizaje supervisado, así como el nivel de exactitud en predicciones obtenidas con modelos tradicionales de progresión lineal y con una RNA entrenada (backpropagation).

Sep 20, 2019

Certain information contained herein regarding Champion Minerals Inc., including management?s assessment of future plans and operations, may constitute forward-looking statements under applicable securities law and necessarily involve risks, including but not limited to risks associated with mining exploration, operating costs, production costs, volatility of share prices, currency fluctuations, imprecision of resource and reserve estimates, environmental risks and ability to access sufficient capital from internal and external sources. As a consequence, actual results may differ materially from those anticipated in any forward looking statements. Plans, intentions or expectations disclosed in any forward-looking statements or information should not be read as guarantees of future results or events, and will not necessarily be accurate indications of whether or when or by which such results or events will be achieved. Except as required by law, Champion Minerals Inc., expressly disclaims any intention and undertakes no obligation to update any forward looking statements or information as conditions change. The historical mineral resources mentioned are strictly historical in nature and are non-compliant to National Instrument 43-101 mineral resources and mineral reserves standards, and should therefore not be relied upon. A qualified person has not done sufficient work to upgrade or classify the historical mineral resources as current National Instrument NI-43-101 compliant.

May 1, 2011

By N. Loganathan, Tan Boon Tee, Joe O’Carroll, Richard Flanagan

In recent years, tunnelling activities in Singapore have increased considerably with the construction of extensions to the existing sub-surface transport system, a deep tunnel sewerage disposal system, and tunnels for the laying power cables and other utilities. These tunnels are excavated through urban areas, adjacent to high-rise buildings, depressed road structures, beneath other tunnels, and buried services. Earth pressure balance (EPB) tunnel boring machines (TBM) have been used extensively in Singapore with great success. The risk associated with soft ground tunnelling, including tunnelling through Old Alluvium, can be minimized with an understanding of the geology, geotechnical parameters, and the tunnelling-induced behaviour of Old Alluvium (OA The purpose of this paper is to present some design and construction aspects of EPB TBM tunnelling through Old Alluvium.

Jan 1, 2005

By Barara Rose

Presentation Outline ?Introduction of BMS ?Resource Integration Process ?Methodologies ?Tools ?Case Studies ?Zone 01 : 725 SOZ ?Zone 16/17 : 1000 NRP ?Conclusions

Oct 1, 2010

By James P. Stewart

This case history describes the engineering design and construction for the Contractor of a 35-ft-deep excavation for an 800-square-foot addition to an existing sewage pump station. The site posed unexpected geotechnical complications that included deep gravelly soil, a history of local construction difficulties, groundwater consisting of heavy salt brine, and the need to underpin the existing pump station. The project took an interesting twist when the Owner issued a change order limiting the dewatering discharge to a fraction of that required to lower the water table. This documents the interesting circumstances of this job and documents the unusual subsurface conditions in the Syracuse, NY Lakefront area.

Jan 1, 2003