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By Gungor Tuncer, Ali Kahriman, Abdulkadir Karadogan, Umit Ozer, Ertugrul Kaya, Kagan Ozdemir

The results of bench blasting on quarries, have important influences on the performance of subsequent mining activities such as loading, hauling, crushing, grinding etc., and the total costs of that mine. Drilling and blasting is an important step in mine producing chain and its results such as fragmentation, muckpile shape and looseness, dilution, damage and rock softening effect the efficiency of downstream processes. Within the scope of this study, the three different hydraulic excavators’ working performances have been studied considering the particle size distribution after bench lasting at a quarry in Istanbul Turkey. Five shots have been realized on the quarry and average particle size of muckpile after each shot were assessed by digital image analysis method. Bucket loading times have been measured by stopwatch study after five shots. Excavator bucket loading times were also estimated by bucket loading time estimation formula which was published in ISEE 2007 Conference, Ozdemir et al. 2007. Estimated and measured times have been statistically analyzed and the accuracy rate of formula has been determined for five events.

Jan 1, 2008

By Shigehito Deki

"A new wet process has been developed for the synthesis of various kinds of oxide thin films on various kinds of substrates, even which have complex surface morphology, from aqueous solution. The process was named as the LPD, Liquid Phase Deposition, method, which has some advantages over the conventional dry processes. This process can be applied to an on-site synthesis of advanced materials in the thin film technology. In this paper, some current topics on the synthesis of the composite thin oxide films by the LPD method, are presented.IntroductionGenerally, metal oxide thin films have been made by different preparative processes such as r.f. sputtering, chemical vapor depositon, CVD, laser ablation and sol-gel method, etc [1-3]. Each method has it own advantages and disadvantage. In some cases, the process is not suitable for the preparation of thin film on substrate with large surface area or complex surface morphology, and makes the deposition apparatus complicated and expenisve. By using Liquid Phase Deposition, LPD, method which overcomes some of those problems, metal oxide or hydroxide thin film can be formed on the substrate with large surface area and complex surface morphology, which are immersed into the aqueous solution only at ambient temperature and under atmosphere without any special equipments and high energy. And also, multicomponent oxide thin films can be formed readily by mixing solutions containing the objective metal ions, because it is performed in the aqueous solution which is typically a homogeneous mixing system. This process utilizes ligand-exchange, hydrolysis, equlibrium reaction of metal-fluoro complex species, MF x (x-2n>-, and F consumptive reaction. In the aqueous solution, MFx<x-2n>-is hydrolyzed with water to release F ions by a ligand exchange equilibrium reaction as following;"

Jan 1, 2000

By J. P. Neumann, L. Raymond

At temperatures near 1000°C, only the (112) (111) slip systems are operatire in tungsten. Therefore, the substructure introduced into the billet upon rleforming a single crystal by rolling at 1000 "C can be controlled by proper selection 01. processing ral&apos;iubles. Using a reduction of 10 pct pel- pass, the (001)[110] and the (110)[001] crystals will deform by duplex slip rip to a 50 pet reduction in thickuess. These rolled single-crystal sheels are characlerized by anisotropic hardening, retention of ductility with warm working, lattice bending which is related to the conlacl (angle, and macroscopic dimensional changecs in the length bid not the width of the billet. When several slip systems become operative, a greater degree of work hardening is itztvoducetl into the crystal. This rolling- condition is characlerized by isotropic hardening, loss of ductilily with warm working, complex lattice distortions, and macro-scopic dimensional changes in both the length rind Width of the billel. IN tungsten, the {1 10}(111) slip systems are operative below room temperature,&apos; while above 700°C only the {112{ (111) slip systems are observed.2,3 In the transition region, i.e., room temperature. both systems appear. It is the purpose of this investigation to show that tungsten single crystals deformed by rolling at a temperature where only one slip system is operative generate dislocation substructure which depends on the crystal orientation. For a specific crystal orientation. the resulting dislocation substructure can be further influenced by modifying the rolling procedure. Crystals oriented for multiple slip display less substructural sensi- tivity to modifications in processing techniques than do single crystals oriented for duplex slip. Under simple slip modes of deformation, very little work hardening is introduced into a rolled single-crystal sheet. Mechanical properties such as room-temperature strength. ductility, and hardness are used to confirm the existence of the different work-hardened conditions generated within the crystal by modified warm-rolling techniques. EXPERIMENTAL PROCEDURE Material. Single-crystal billets of four different crystal orientations. grown by the Arc-Verneuil technique. were ground to a size of 0.25 by 0.375 by 3 in. In terms of their rolling plane and rolling direction, the billets had the following orientations: (1101 [001 ] (110) [110] (001) [110] (001) [100] The actual orientation of all crystals was within 5 deg of the ideal orientations. The typical impurity content of the crystals is given in Table I. Polishing and Etching. Polishing was done elec-trolytically in a 20 g per liter aqueous solution of NaOH at approximately 10 v. It was established by the Laue back-reflection X-ray technique that the surface damage due to grinding and cutting operations with a diamond wheel did not exceed 0.001 in. Therefore after each cutting or grinding operation at least 0.002 in. was removed electrolytically from the surface in order to eliminate surface effects. By lowering the voltage to 3 v, subgrain boundaries and individual dislocations are identified in agreement with Berlec 4 where the etch-pit traces on a cubic plane form a square. The etching time was about 5 sec at room temperature. Rolling. Rolling was carried out on a Loma 2-high mill (Model 600). The peripheral velocity of the 6-in.-diameter rolls was 500 in. per min, with the surface temperature of the rolls about 400° to 450° C The billets were heated before each pass for 30 min in argon to 1000 C. Oxidation of the crystals during rolling in air resulted in a thin layer of greenish-yellow WO 3 This oxide was removed after each pass by immersing the crystals for a few minutes in a boiling NaOH solution. Prior to the initial rolling pass, a surface layer of 0.001 in. was removed by polishing. The crystals were then annealed in vacuum (10-4 torr) at 2400 C for 30 min. All crystals were rolled in the same direction; i.e., the same end was always introduced into the rolls. The rolling program was conducted in

Jan 1, 1965

Previous published papers by Fraser (1), Hey (2), and Stillwell (3), have given respectively, details of:-1. The practice in the pilot plant operated at Zeehan for the treatment of ores from the Rosebery field.2. The design, based largely on the experience gained at Zeehan, of the concentrator built at Rosebery.3. The nature of the orebodies of the zinc-lead lode at Rosebery.Changes and developments, at the Rosebery concentrator, since operations commenced, are now described with particular reference to recent practice.Three concentrates are produced, viz.: a copper, a lead, and a zinc concentrate. The current flow-sheet is shown in Fig. 1. Typical concentrate assays are...THE OREThe ore treated is derived from the Rosebery and Hercules Mines and is, milled in the ratio of, approximately, two parts of the former to one of the latter. The ores from the two mines may be considered as being similar in general character, although the Rosebery ore contains more pyrite. It is from this mine that any increased tonnage is expected. The ore is a mass of fine-grained, intimately associated sulphides, with practically no coarse...

Jan 1, 1949

By Louis H. Berkelhamer

"INTRODUCTION ""Free silica"" includes all free forms of silicon dioxide, such as quartz, chalcedony, tridymite, cristbbalite, opal, diatomaceous earth, and lechatelierite. The term, has been used rather loosely however, as synonymous with quartz, as quartz is the most abundant form of free silica. ""Combined silica,"" on the other hand, has been reserved to denote silica combined with other elements as silicates.Improvements in methods for the determination of free silica, and quartz in particular, have been the subject of considerable interest during the past decade, owing mainly to the accented and increased knowledge concerning quartz as a causative factor in silicosis. Analysis for quartz, however, is of importance in many other fields, including the determination of quartz in ceramic raw materials, such as feldspar and clay; the evaluation of a beneficiation procedure by the ore dresser, such as in the concentration of iron ore; control studies of a manufactured product, such as silica brick; and routine analysis of rock, mineral, and ore samples by chemists and petrographers."

Jul 1, 1944

By Joshua Micah Hoffman, Jhon Silva-Castro, Kylie Larson-Robl

A coal mine impoundment failure has the potential to be environmentally devastating and life-threatening. It is well documented that after seismic events slope failures in impoundments can occur. It has been concluded that often the main driven factor of the failure is the increase in excess pore pressure due to ground vibration. A small amount of research has been done regarding the stability of coal mine impoundments under natural seismic events; however no research has been done considering vibrations from mine blasts. If it is taken into account that current environmental restrictions oblige to increase the capacity of coal mine impoundments, thus increasing the hazard of such structures, it is necessary to evaluate the effects of near-by mine blasting on the stability of the coal mine impoundments in order to mitigate and control the potential of slope failures. To study the behavior of excess pore pressure under blasting conditions, scaled simulations of production blasting events were set up inside of a controlled sand tank. The research was divided in two stages. The first one was done, using dry conditions, while in the second part, the same set of tests were performed under saturated conditions. This document shows the partial results for stage one (dry conditions). For the tests, explosive charges were set off within the sand tank at various distances to simulate different blasting distances. Information was collected from geophones, accelerometers, microphones and high speed video camera for dry and saturated scenarios and additionally from piezometers under saturated conditions to assess the behavior of the material under blasting conditions.

Jan 1, 2015

By Rafael Abreu Fraga

Foram avaliados os efeitos da tecnologia de laminação seguida da têmpera direta na produção de chapas grossas de alta dureza, resistentes à abrasão, na Linha de Chapas Grossas da Gerdau Ouro Branco. Para tanto, foram analisados os parâmetros de processo e propriedades mecânicas, através da realização de ensaios de dureza, tração, tenacidade ao impacto Charpy e metalografia. A tecnologia de têmpera direta, realizada através do Mulpic, possibilita a fabricação de aços de alta dureza com carbono equivalente significativamente baixo. O mecanismo principal para aumento da dureza, baseia-se em uma laminação com passes de alta redução, iniciando o resfriamento com o aço ainda constituído exclusivamente pela fase austenítica, sendo temperado a baixas temperaturas, ocorrendo a completa transformação martensítica. Tanto o processo de têmpera direta no Mulpic, quanto os processos anteriores precisam ser muito bem controlados, visando uma microestrutura homogênea e um produto com a planicidade adequada.

Oct 30, 2017

By Anderson Meireles, Vladimir Carrasco, Carlos Feliciano

Adopting new technology in drill and blast requires a structured implementation process, as it represents a significant change in a traditionally conservative industry. It involves addressing initially unknown implications. As the problem is not yet acutely felt, developing a market strategy must be approached from the customer’s perspective, considering how the product can optimize their activities or enhance flexibility. To achieve this, it is essential to have a comprehensive understanding of the context of the customers identified in the deployment process pipeline. This paper discusses aspects of introducing wireless initiation technology - the initiation of primers through a magnetic field without physical connections - in Brazil. Additionally, it presents a case study of the application of a structured process of sales with purpose in an underground mine. By identifying key opportunities that were highly profitable for the client, the necessary awareness was created, leading them to recognize the technology as an enabler for exploring their mineral deposits in a new way which allowed a successful change management process. Based on the applicable technique, a preloading project was developed to maintain inaccessible areas with high-grade precharged with the area loaded with wireless primers acting as a temporary pillar and controlling dilution throughout the orebody. Once the excavation of the stope was completed, the pillar was successfully blasted and the material - once considered lost in the original plan as a rib pillar - was recovered after serving its structural function. Through this method, the metallic recovery of the stope increased without dilution losses. Demonstrating economic viability and stablishing the previously unknown technology as a strategic tool for optimizing stope recovery.

Jan 21, 2025

By Gilberto Thiago de Paula Costa

Este artigo apresenta o SALF, um software nacional desenvolvido para simular o processo de laminação a frio de chapas através do método dos elementos finitos. O programa utiliza a formulação implícita/rígido-plástica em suas análises. Simulações retiradas da literatura foram realizadas com o software, sendo os materiais simulados alumínio e aço, com espessuras de 3,0 mm e 1,0 mm, reduções de 5% e 30% e atrito de 0,06 a 0,15. Os resultados do SALF ficaram bem próximos dos resultados descritos na literatura. Desta forma, a partir de agora, as siderúrgicas nacionais têm uma ferramenta nacional para simular o processo de laminação a frio, a qual pode auxiliar na melhoria de seus processos e produtos.

Aug 17, 2017

By H Arvidson, J Vann

When only wide-spaced drilling is available, for example at concept, prefeasibility and feasibility stages, properly implemented linear estimation (including ordinary kriging) predicts grade tonnage relationships that are over-smoothed compared to final production estimates (and production). Non-linear estimation and conditional simulation are alternative geostatistical approaches that can provide more reliable estimates of the recoverable tonnage and grade from wide-spaced drilling. Non-linear estimation and conditional simulation have been rarely used on iron ore deposits. However, these techniques have had wide application in other commodities such as gold and base metals. Conditional simulation has been used in the iron ore industry (eg Guibal et al, 1997); however, its use here is outlined as a means of generating non-linear estimates, not just its use for variability and drill spacing analysis. As a rule, regardless of commodity, the decision to use non-linear geostatistics will necessitate increased skills and require more time. This decision must therefore be justified in terms of cost-benefit. Such cost-benefit analysis is not straightforward, and to help an approach for determining when linear estimates are inadequate is presented. Recommend in this paper is a well-established non-linear geostatistical approach, the global ædiscrete Gaussian modelÆ (DGM) of change of support, as a tool to establish whether moving from linear to non-linear estimates will materially improve estimate results. Also discussed is the additional use of DGM as a block model validation tool. One specific factor contributing to the lack of application of non-linear geostatistical methods in iron is the added difficulties that arise when conditional simulation and non-linear estimates are required to reproduce the numerous and often important correlations between variables in iron ore deposits. Consequently, presented in the paper is a synoptic review of non-linear estimation and simulation methodologies applicable to correlated variables.

Jan 1, 2007

By Rudá Grossi Coimbra Martins

A estruturação organizacional da gestão da informação em Central de Serviços já está consolidada no ambiente de Tecnologia da Informação. O ambiente de Tecnologia de Automação compartilha características semelhantes, já que também fornece serviços para seus clientes. Entretanto, serviços de automação possuem particularidades derivadas, em grande parte, do fato de que são mais críticos para a atividade fim da empresa, já que visam manter a operação. Implantar uma Central de Serviços em ambiente de Tecnologia de Automação de uma empresa já existente demanda uma série de modificações em termos de Tecnologias, Processos e Pessoas para trazer os retornos desejados em termos de gerenciamento, organização da rotina e disponibilidade dos ativos. Este trabalho apresenta alternativas para atuar sobre os três componentes supracitados durante a implantação de uma Central de Serviços, com foco em sua operação através de uma Gestão Compartilhada (Cosourcing). Experiências adquiridas em projetos de especificação e operação de Central de Serviços também são apresentadas para embasar a estruturação da gestão da informação em ambiente de Tecnologia da Automação de indústrias de Metais e Mineração.

Jul 30, 2018

By D P. Blair

Various analysis techniques are used to determine the nature of a large seismic event that was triggered by a mass blast in an underground mine. This event was recorded by surface accelerometer arrays whose output was doubly integrated using a stable filter to determine the dynamic displacements. The peak dynamic displacements during the blast were 0.09 mm, and during its latter stages, this blast induced a seismic event having a peak dynamic displacement more than ten times larger at 1.26 mm. Polarisation analysis, based on the complex covariance matrix, showed that the seismic event was caused by movement of a known underground fault, close to the blast, which radiated most of its release motion as a shear-horizontal (SH) wave. The change in frequency content with time for the blast and seismic event was initially determined using the Fourier-based reassigned S-method. This analysis showed that the large amplitude seismic event had frequency content significantly lower than that of the blast. Nevertheless, this Fourier technique still retains the problems associated with short time windows as well as the fact that most realistic signals are non-stationary. In order to eliminate such influences, the more recently developed empirical mode decomposition (EMD) was used to obtain the intrinsic mode functions (IMF) of the seismic wave propagation. The EMD vibration analysis showed that each IMF generally exhibited distinct frequency changes throughout the blast and a significant reduction in frequency throughout the subsequent event. It is shown that most of the energy of the seismic event is contained in IMF modes 2, 3 and 4 of the SH wave; the high-frequency first mode (IMF1) contains little energy. Such modal analysis is not possible using standard Fourier methods.CITATION:Blair, D P, 2015. Dynamic displacements from a blast-triggered seismic event, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 203–210 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By Elisa Araujo Santos Darsie

A busca na melhoria da qualidade dos aços, principalmente no caso de aços limpos, fez com que o distribuidor de lingotamento continuo também seja empregado para a remoção das inclusões responsáveis por prejudicar as propriedades mecânicas dos aços. Uma melhor eficiência desta função do distribuidor pode ser atingida com o conhecimento das características do escoamento do banho metálico de modo que se possam propor modificações na configuração do distribuidor. Esses fenômenos de escoamento e remoção de inclusões podem ser simulados mediante a utilização da modelagem física. O objetivo deste trabalho é avaliar quatro configurações internas de distribuidor por meio da qualificação do escoamento via ensaio de linhas de fluxo e quantificação de inclusões passantes pelo veio com o ensaio de remoção de inclusões. As variáveis de controle utilizadas neste estudo são: velocidade de lingotamento, presença de barreiras e presença de tubo longo. Os resultados apresentados para o distribuidor em questão mostram que para os casos com o tubo longo, o uso da barreira torna o escoamento predominantemente ascendente eliminando o curto-circuito e favorável a remoção de inclusões passando de 29,76 para 24,29% de inclusões passantes pelo veio. Enquanto que para os casos sem tubo longo, o uso da barreira proposta diminuiu o contato do aço com a escória sobrenadante, aumentou o curto-circuito e aumentou também o percentual de inclusões passantes pelo veio de 2,56 para 3,01%.

Aug 8, 2018

By Tyler J. Irving

"In June, 2018 Lalor Mine experienced a catastrophic blade failure of its No. 2 main exhaust fan. Over the following weeks several key changes were made to the auxiliary ventilation system to allow for continued production while the exhaust fans were repaired. Issues encountered during the period of reduced ventilation, and how they were addressed, are analyzed. The suspected causes of the exhaust fan blade failure and how risk was mitigated during the reconstruction are discussed. Key findings and lessons learned are summarized.INTRODUCTIONLalor Mine, owned and operated by Hudbay is an underground zinc, gold, and copper mine located in northern Manitoba. The mine workings extend to a depth of 1090 metres below surface and is ventilated using a push-pull system. The mine exhausts through the main exhaust raise; equipped with two, 2,500 HP fans and upcasts through a portal located at the neighboring mine, Chisel North. Air is supplied to Lalor Mine through four intake fans: The Production Shaft Downcast (two, 250 HP), Lalor Downcast (one, 400 HP), and Chisel Downcast (one, 600 HP) fans (Figure 1). In June 2018, Lalor was scheduled to produce approximately 4,000 tpd.On June 20, 2018 at 2:52 pm Lalor Mine experienced a fault on the Variable Frequency Drive (VFD) for Exhaust Fan No. 1. Time would be needed to complete the necessary repairs. The No. 2 exhaust fan was ramped up from 525 rpm to 800 rpm, 90% of its capacity, in order to maintain underground ventilation. At 4:46 pm, approximately two hours after the rpm was increased, exhaust fan No. 2 experienced a catastrophic blade failure. The forces from the blade failure resulted in the top half of the fan housing being thrown 50 metres from where it was installed; with several large sections of fan blade being thrown further (Figure 2)."

Jan 1, 2019

By Charlie Wyche

The British Solomon Islands Protectorate continued developmental work on bauxite deposits on the Islands of Rennell and Vaghena. A feasibility study was completed by Mitsui Mining & Smelting Co., Ltd., and Pacific Aluminum Ltd. (a subsidiary of Conzinc Riotinto of Australia Ltd,), and negotiations with the Government were in progress. The Government will receive a 25% share if the project is realized. It was estimated that the Islands contain 60 million tons of bauxite with an alumina content of 45% to 50%.

Jan 1, 1980

By R. L. Blake

The crystal structure of hematite, a-Fe203, has been refined as part of a continuing study of the behavior of phases in the Fe-O system during reduction and oxidation. Three-dimensional diffraction intensities were collected on two spherical single crystals of hematite with a semiautomated Buerger single-crystal diffractometer. The first crystal refined was a natural Elba hematite with minor impurities. The other, a synthetic crystal, was refined at the request of Mossbauer spectroscopy investigators concerned with impurities in the natural crystal. The structure has been refined with a least-squares program and the final structure for the natural crystal irradiated with CuKa-radiation gave a discrepancy factor (R) of 3.65 percent using 49 unrejected reflections of the 51 measured. For the synthetic crystal, using MoKa-radiation, the discrepancy factor converged to 2.8 percent using 95 unrejected reflections and was 3.3 percent for all 109 reflections. The structure model of Pauling and Hendricks has been confirmed with essentially no change in the iron coordinates and approximately a 5-percent change in the oxygen coordinates. Selected interatomic distances and angles were calculated as were anisotropic temperature factors.

Jan 1, 1970

By Jason Rrno

The emergence of Impact and Benefit Agreements (IBAs) in the Canadian mining sector has been read by many as a positive governance innovation. Negotiated directly between mineral resource developers and Aboriginal communities with limited government interference, IBAs serve to manage impacts associated with a mining project and deliver tangible benefits to local communities. Notwithstanding their increasing use and significance, limited systematic analysis has been undertaken to determine whether they are, in fact, working. This paper reports on the effectiveness of a number of IBAs negotiated in support of three northern Canadian diamond mines, drawing on evidence from time-series data, key informant interviews, and focus group meetings in Yellowknife and Dettah, NWT, and Kugluktuk, NU. While some deficiencies were apparent and perceptions of effectiveness varied somewhat by Aboriginal community, the IBAs were generally found to be meeting their objectives, especially with respect to the delivery of benefits. For Aboriginal communities affected by mineral development in the Canadian North, this represents a significant change to typical outcomes of the past. Moving forward, research on IBA effectiveness needs to adopt a longer timeframe and begin to gauge the degree to which IBAs are able to address long-standing concerns associated with hinterland resource extraction beyond their agreement-specific objectives.

May 1, 2010

By A. B. Pederson, G. E. Bartlett

As a part of our study of how coal mine dusts injure the lung we have studied the effects of dusts and dust-exposed pulmonary alveolar macrophages (PAMs) on the growth of lung fibroblasts (LF). Fibroblasts were cultured near confluence in low-serum medium, either alone or in the presence of dusts, dusts plus PAMs, dust leachates or superriatants of dust-exposed PAM cultures. We report here provisional conclusions, based on initial observations. Rat LF were relatively unresponsive to direct effects of dusts, showing weak stimulation in only a few cultures, and there was no evidence that dust-exposed rat PAMs had released any growth-regulatory products. In contrast, guinea pig cells were more responsive to the dusts. The pattern of responses was quite complex. Three of the dusts stimulated LF directly (with no mediation by PAMs). Two dusts were essentially inert when added directly to fibroblast cultures, either with or without PAMs, but their leachates were active: 867 leachate was inhibitory and RF leachate was stimulatory. Dust 1361, either directly in the cultures or as an aqueous leachate, was stimulatory, and it activated cocultured PAMs to stimulate LF growth; however, supernatant products of 1361-stimulated PAMs were inhibitory. Direct exposure to 1192 stimulated LF, but its leachate was inert; cocultured PAMs exposed to 1192 had weak stimulatory effects, but supernatants of 1192-exposed PAMs were mildly inhibitory. MP3-3 had effects similar to 1192, except that the cocultured, dust-exposed PAMs had no effect on growth. We conclude 1) that guinea pig lung cells are more responsive to dusts than are rat lung cells, 2) that dusts can influence growth of LF by four kinds of interaction (by direct dust-cell interaction, by release of soluble dust components into the culture medium, by activating P AMs to exert direct cell-cell interactions, and by activating P AMs to release growth regulatory products into the culture medium), 3) that each kind of interaction may be neutral, inhibitory or stimulatory, depending on the dust tested, 4) that four of the dusts tested were neutral, inhibitory or stimulatory, depending on the assay (the fifth <lust was either neutral or stimulatory), and 5) that the effects of soluble mediators (leachates or products of activated PAMs) frequently did not correspond with the direct dust-cell or PAM-fibroblast effects. These results suggest that the nature of the dust-lung interaction at the level of cells and molecules is exceedingly complex. These observations need to be confirmed and extended to determine what characteristics of the dusts determine the nature of the cellular responses, and to determine which patterns of responses are detrimental and which are beneficial in the overall health of the dust-exposed lung.

Mar 1, 1989

By Jorge Oviedo

La planta de lixiviación, extracción por solventes y electrodeposición (L-SX-EW) de Southern Perú es una operación hidrometalúrgica dedicada a la lixiviación ácido – bacteriana de los botaderos de mineral de baja ley de la Mina Toquepala, para la producción de cobre catódico de la más alta pureza. En ese sentido, el presente trabajo describe la evolución del sistema de control y supervisión de esta planta minera en Cuajone. Para ello, dicha planta debe tener una actualización constante de sus sistemas de control y ser capaz de cambiar con la velocidad a la que avanza la tecnología de Control de Procesos. Asimismo, debe contar con personal calificado que permita el desarrollo y modernización de los sistemas sea continuo y no dependa solo de expansiones y ampliaciones ejecutadas por especialistas externos. De forma que este software de supervisión, no solamente considera la capacidad de operar la planta, si no debe ser una ayuda tanto para el operador como para brindar información en la correcta toma de decisiones.

Aug 25, 2002

By Elli Nurminen

In this work the thermodynamics of the metallic sulphate decomposition reactions were studied through thermodynamical calculations and thermogravimetric methods. The decomposition temperatures and mechanisms were determined for cupric sulphate, ferric sulphate and also for industrial flue dust from a copper flash smelting process. The aim was to determine the thermodynamic conditions for sulphate decomposition and to estimate whether the reactions are kinetically likely to take place in the flash smelting process heat recovery equipment. The information is essential in CFD-modelling of the reactions taking place in the boiler and for optimising the process.

Jan 1, 2006