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By C. J. Kirkland

For two thousand years and more, we insular Britons have been grateful for the existence of the narrow strip of water that separates us from mainland Europe. It has given us a sense of security against invaders, though it has been breached many times. The first recorded serious consideration of a fixed crossing of the English Channel was in around 1802, when it was suggested to Napoleon I. The motive was not entirely peaceable and the British Navy, who saw themselves as defenders of our shores, were decidedly unenthusiastic A whole series of imaginative schemes were proposed in the course of the nineteenth century, embracing viaducts, immersed tubes, artificial islands as resting places for the horses which were to draw carriages, as well as mechanically bored tunnels. The first Channel Tunnel Company was formed in 1872, and an application for permission to construct a tunnel was made to the British parliament. A Colonel Beaumont, of the Corps of Royal Engineers designed and constructed a machine which, in around 1882, bored over a mile of tunnel out to sea from Britain which exists to this day.

Jan 1, 1991

By D van der Wal, R Dobbe, K Moeller

"Ore mineralogy and texture are primary variables controlling mill recovery efficiency in flotation plants. However, tracking daily variations of key mineralogical characteristics such as species-by-species liberation is not possible with current on stream analysers and assay lab techniques. In addition, traditional plant mineralogical analysis limited by long data turn-around times from central analysis laboratories typically provides only a time-averaged view of mill performance, e.g. by means of monthly composite feed, con or tailings analysis.This paper presents the results of a development and first field test of an on-site Automated Mineralogy solution (MLA or QEMSCAN) with the specific goal of monitoring recovery variation, ore quality and flotation performance on a mineral species-by-species and day-by-day basis, from up to twelve million direct particle observations per month. The trial was performed at a Pb/Zn-Ag operation in the US from November 2012 to April 2013. The focus of the study was three-fold: to validate the robustness of equipment and operational procedures for daily use by mine site technicians at a remote mine site to develop a methodology to boil down hundred-thousands of Automated Mineralogy particle data from size-by-size con and tailings samples to a couple of numbers meaningful to chief metallurgists to monitor recovery trend changes and correlate these to changes in the feed properties and/or flotation efficiency.The study focused primarily on the Pb/Ag rougher-concentrator circuit. Ten polished blocks of two and three size fractions of con and tailings were prepared by mine site technicians during a daily twelve hour shift. Eight hours of daily measurement time by the instrument revealed an estimate of the dayÆs recovery performance, ore quality and flotation performance for Freibergite (Ag-species) and Galena (Pb-species), within 36 hours from initial sampling. Data quality was assessed by means of calculated versus measured assay reconciliation. Cumulative sum curves of recovery performance, ore quality and flotation performance reveal trend changes with a frequency of 1 to 4 weeks. These were correlated to cumulative sum curves of e.g. locked and slimed particle classes of the mineral species of interest, attempting to identify a possible root cause of recovery performance trend changes. Systematic over-grinding and flotation chemistry issues were the primary causes of below average plant operations during the trial.CITATION:van der Wal, D, Dobbe, R and Moeller, K, 2013. Development of an on-site mineralogy solution for metallurgists, in Proceedings MetPlant 2013, pp 126-132 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 15, 2013

By Rajendra Singh

Underground depillaring of contiguous coal seams/sections is a difficult problem, which becomes even more complex if the interburden/parting between them is thin. Conventionally, the depillaring with caving of contiguous seams/sections is done in descending order. However, if the parting is thin, the influence of the top sections/seams working over the standing pillars of bottom the sections/seams becomes extremely important for the safety and optimal exploitation of coal. Field investigations were carried out at Nowrozabad East mine where superimposed pillars of the Johilla top section were depillared above the developed pillars of the Johilla bottom section with a 3 m thick parting between the two sections. The competency of the 3 m thick parting (which consists of alternate layers of shale, sandstone and shaly sandstone) was improved by reinforcement (underpinning). The strata control investigations did not show any considerable instability problem of the 3 m thick reinforced parting and pillars of the bottom section due to top section depillaring. On the basis of this field investigation and a laboratory study on simulated models, simultaneous extraction of both the sections, along with reinforcement of the parting, was suggested for the geomining conditions of the Johilla top and bottom sections. Adopting the suggested simultaneous depillaring process, two sub panels of Johilla top and bottom sections have successfully been extracted without any strata control problem. This paper presents this case study along with the results of the strata monitoring conducted to evaluate performance of the underground structures during the field trial.

Jan 1, 2004

How did you get into mining; were you from a mining town or mining family? Not at all. I grew up in northwest Kansas. I liked to hunt and fish, so I thought it would be fun to work for a company that made knives or guns. It seemed like metallurgical engineers would be something those companies could use, so I started in physical metallurgy. I got a summer job at the great Climax molybdenum mine near Leadville, CO shoveling muck onto conveyors. I was hooked. I loved everything about mining, so in the fall, I changed majors from physical metallurgy to mineral processing. For many years you actually discouraged young people from studying the mining disciplines. Could that be right? That’s true.

Jan 1, 2007

By Joseph C. McCaskill

The writer assumes that this volume is not intended to serve as a source of statistics on international trade and that the reader is not interested in wading through a lot of statistical tables copied from the various reporting agencies. Generalizations therefore are made whenever possible and not always is the source of the information meticulously cited. The United Nations regularly publishes trade data on mineral commodities. E. J. Gealy, and C. L Kimbell, of the U S Bureau of Mines (USBM), work with these data and estimate that they cover approximately 78% of total mineral commodities traded. In addition the General Agreement on Tariffs and Trade (GATT) publishes analyses of certain trade data The most complete report of production and trade in minerals 1s probably the international volume of the U.S. Bureau of Mines Yearbook The latest available edition is for 1968, and some of the data in this edition cover only as late as 1967. Unless otherwise stated, the source of data used in the chapter is this Yearbook Other staff members of the Bureau were most helpful and cooperative They are not to be held responsible for conclusions or points of view to be found in the chapter. THE NATURE AND SCOPE OF INTERNATIONAL TRADE The two and a half decades since World War II have witnessed an unprecedented growth international commerce The end of the war found the world economy seriously crippled. Many countries had suffered severe war damage; international trade was disrupted and nations had to resort to exchange controls and bilateral trading arrangements. The postwar recovery, however, was remarkably rapid Within two decades, world Income more than doubled, and world trade which was less than $60 billion in 1948 exceeded $200 billion in 1968, 8 and reached $278 billion in 1970.18 The growing world trade contributed to world prosperity which in turn fostered growth of trade. This dramatic growth of international commerce was made possible by the progressive liberalization of trade and capital movements by the major trading nations of the world which began immediately after the War and has not yet completely lost its steam. The modern-day stimulus of the expanded trade movement was the enactment by the Congress of the United States in 1934, of the

Jan 1, 1976

By Bill Kyslinger

In underground mining, machine design is predominantly dictated by mine conditions and individual customer desires. In partnership with Boart Longyear Poland and KGHM, J. H. Fletcher & Company was tasked to design and manufacture a single-boom, single operator drill module for installation of 1.2 meter expansion bolt in a 1.6 meter height mine. The objective was to produce a machine to provide ergonomic improvements for the operator while working in the mine environment. This dictated the requirement for a small easily controlled, maintenance friendly design with a remote operator?s control station. The selected design method was to use starter and finisher drill steels. This combination, requiring a number of mechanized machine motions, provides the ability to drill the required depth in the specified mine height. To accomplish the task from a remote location, a conscious decision was made to employ current technology in the form of small pressure compensated hydraulics and electronic controls. The result of the design method is a modular assembly with each sub-component designed to be replaceable and adjustable independently from other machine components. The low profile remote roof bolting module is made up of six major sub-components. Each major component is painted a different color to help the operator make the visual connection from the drill module to the operator?s control/display monitor. The Stabilizer (White) secures the module between the mine top and floor. The Drillhead (Orange) produces the drilling rotation and torque but also must slide out of position to allow the machine to manipulate the drill consumables. The Drill Steel Carousel (Blue) holds and indexes the starter and finisher steel from position to position. The Manipulator Arm (Green) moves and guides the drill steels and drill consumables from position to position during installation. The Roof Reference Guide (Yellow) locates the mine roof and guides the drill steels and drill consumables into position. The Linear Bolt Carousel (Purple) holds the drill consumables. The low profile remote roof bolting module allows the operator to drill and install a roof bolt manually or automatically with the push of a button. This design substantially reduces the operator?s exposure in the mine environment, as well as inherent pinch points and rotary hazards. Positioning the operator safely in the confines of the air conditioned cab.

Jan 1, 2006

By Richard E. Gray

Subsidence due to coal mining is poorly understood by non-specialists. This has led to numerous misconceptions and myths based on limited observations and lack of knowledge. The three most common are: 1. Mine maps are inaccurate. 2. Deep mines are not a problem. 3. If no subsidence has occurred for many years after mining, there is no risk of future subsidence. Maps are important during mining and most are carefully prepared. Future use to evaluate conditions at mine level often includes drilling to confirm what the map shows. Usually, little or no effort is made to tie the surface survey of the property to the mine survey, to conduct a well designed drilling program to confirm the mine map, or to drill test borings vertically. When a mine entry is encountered rather than a coal pillar, or vice versa, and conditions at mine level appear different than anticipated, the first reaction is the mine map is inaccurate. The idea of a safe depth from subsidence is often based on the false premise that mining results in sufficient breakup of the overlying rock strata that bulking compensates for the coal extracted. The safe depth idea first appeared in the literature about 1880 and remained prevalent well into this century. Sadly, it is still encountered. The modern understanding of fragmentation of the immediate mine roof with the overlying beds sagging down on the broken roof rock was first described in 1900. With full extraction mining, either longwall or retreat room and pillar, surface subsidence occurs regardless of the depth of the mine. Subsidence over longwall mines at depths of 2000 feet can be 90 percent of the mined seam thickness. Numerous studies of undermined sites conclude that mining occurred many years ago and since no subsidence has occurred, there is no risk of future movement. This is true if sufficient coal pillars have been left to support the overlying strata. However, every year subsidence occurs over mines that have been closed for 100 years or more. In a study of subsidence incidents over the Pittsburgh Coal, the senior authors found that 50 percent of the incidents occurred above mines that had been closed for at least 50 years and 10 percent over mines closed for at least 80 years.

Jan 1, 1996

By Vu Van Dong

Resource estimation is the science of determining the amount and quality of a given material in the ground that has the potential to be mined at a profit. This is because during this time computers have become more widely available and more powerful and software packages have become more comprehensive and user friendly. Over the past three years The Mining Geology Company with the support from Vinacomin Group has developed the Coal Geological Modelling and Reserve Estimation ? VMG system. The VMG system enables the geological and mining engineer to start at the reserve estimation for the mine design and planning. The VMG system enables the national and international standards (NI43-101, CIM-Canada; SAMREC Code, Africa, and JORC Code, Australia) and user friendly with menu driven thereby permitting the engineer with minimal computer training to rapidly learn and utilize the system. Geological and mining data input through digitized map files and drill-holes information files stored in the database that is an integral part of the VMG system with the main function for collection, validation, and recording, storing and processing of data will include both ?primary? (observation and measurement) and ?interpreted? data. It is recommend that data be stored digitally, using a documented, standard format and a reliable storage medium that allows for easy and complete retrieval of the data. The coal reserve estimation through standard polygon methods with the increased use of these mathematical techniques (geometrical modelling, geostatistical method, least square method, ?) over the last ten years corresponds, to some degree, to a decrease in both the amount of the coal deposit mapping and, in particular, coal seam structural interpretation and modelling, and permit rapidly evaluation of coal seam and overburden quality and quantity. The understanding of the relationship between the coal mineralization of interest and the likely related complicate geological processes and structure that govern its emplacement and geometry within the geological framework is essential to the establishment of the geological controls for coal mineralization. System outputs includes: drillholes summary reports, stratigraphy, cross-sections, isopach maps, structure, contour maps, premining and post mining topography maps, and 3D perspective view on coal seam structure.

Oct 1, 2009

By D. M. Avant, A. J. Solomon, S. M. Pickering, W. R. Fox

Introduction Most high purity silica is produced from crystalline quartz, generally from sand. However, there is a small area of southern Illinois where a porous, friable white chert rock is found that is very different in physical form from quartz sand. This microcrystalline material, commonly referred to as tripoli, is more easily ground to micron sizes than sand. Although of similar Moh's hardness, microcrystalline tripoli is less abrasive than either ground quartz sand or many synthetic abrasives. Location The southwestern corner of Illinois is underlain by extensive deposits of very porous chert; in some places the material is quite white. Two companies, Illinois Minerals Co. and Tammsco Inc., mine and process this white material. The Illinois Minerals plant is located at Elco, and the Tammsco plant is in Tamms, IL. Both companies mine from various locations within a 10-mile truck haul of their plants. Production from this district has been continuous since at least 1915. Malvern Minerals Co. mines and processes a generally similar microcrystalline, friable novaculite near Hot Springs, AR. Geology The southern Illinois white tripoli area is on the southern flank of the Illinois Basin. The commercial silica zone is a facies of the Clear Creek chert of Lower Devonian Age. To the north, where it occurs deep in the basin, the Clear Creek is a siliceous limestone. In the mining area, thin overburden has allowed access by surface ground water, which has leached away the carbonate content and left a quite pure silica residue. Fossils characteristic of sea bottom deposition, such as brachiopods and trilobites, are occasionally encountered in mining. The structure of the mining area is poorly known, due to infrequent outcrops. Strata in most mines are inclined at dips of 5° to 20°. There appear to be occasional high angle normal and reverse faults, but these are seldom of any significance in mining. The friable white silica zone mined in the Clear Creek chert is overlain by dark brownish-red chert and siliceous shale. Exploration drilling to date has not encountered the base of the microcrystalline tripolitic zone. Chemical content Leaching by ground water solution has removed virtually all the carbonate from the original siliceous limestone. Impurities encountered are red to yellow iron oxides, aluminous clays, and occasional black manganese oxides. The silica has no detectable formula water. A typical chemical analysis and physical properties are listed in Tables 1 and 2. Mineralogy and crystallinity Southern Illinois friable tripoli appears amorphous under the polarizing microscope. No crystal structure and only occasional, vague, patchy anisotropism is evident. However, the material gives an excellent quartz X-ray diffraction pattern. Thus, so far as X-ray mineralogy is concerned, the material is clearly

Jan 12, 1986

By Orlando Ramírez

El presente trabajo describe el sistema integrado de seguridad a través de la norma OSHAS 18001 - 1999 y calidad ISO 9001 – 200m, donde la aplicación de la integración controla las desviaciones de los procesos oportunamente. Es decir, que a través de la procalsedad se reúnen tres elementos: productividad, seguridad y calidad,logrando una ventaja competitiva en el mundo globalizado.

Sep 12, 2005

Relatively few longwall mines in the U.S. operate under multiple seam conditions where the two seams are less than 200 ft apart. This paper describes the experience of six that do. These operations are located in PA, WV and UT, and include examples of both undermining and overmining. Some operate above or beneath their own workings, others are in historic mining districts and must contend with abandoned mines that are decades old. The lessons that these mines have learned cover a broad range of topics, including: • Whether to stack gateroads or place them under old gob areas; • How to size pillars and select artificial support to cross longwall stop lines; • How to use yield pillars to minimize multiple seam stresses and coal bump potential, and; • When to anticipate the creation of pathways for gas, water, or oxygen between current and abandoned gobs.

I would like to thank The Australasian Institute of Mining and Metallurgy for inviting us to share with you some of our experiences in the handling, storage, and transportation of industrial minerals in North America. Cometals, Inc. is a wholly-owned subsidiary of Commercial Metals Company, headquartered in Dallas, a public corporation whose shares are traded on the New York Stock Exchange. Sales exceed one billion dollars. Cometals, Inc. is located in New York and specializes in marketing of chemicals as well as raw materials used in the manufacture of steel, refractories, abrasives, glass and ceramics. This makes us one of the larger regular shippers of industrial minerals. Many people are aware that industrial minerals need to be viewed and judged on the merits of their chemical and physical characteristics. In addition you are surely aware that close attention must be paid to the economics of these minerals to determine the appropriate value and competitiveness of the minerals or products delivered at the doorsteps of the consuming work. You may, however, not be aware that the handling and transportation of the mineral is of crucial importance, in fact, the transportation and handling costs of industrial minerals frequently are a major component of the value of the ores marketed and, therefore, it is only natural that close attention should be paid to them. Many of the industrial minerals require special handling to assure that the material reaches the consumer without being contaminated and without getting wet. I invite you to accompany me through the various steps involved in "delivering the goods" to the consumer.

Jan 1, 1989

Considerable improvements in diamond drilling equipment have been made since the early 1950s. A recent drilling programme, however, at Williamtown, near Newcastle, carried out by the Joint Coal Board on behalf of the Electricity Commission of New South Wales, emphasized deficiencies in existing equipment when particularly diflkult coring conditions were encountered.Spurred by unacceptably low recoveries in coal seams in this area, the Joint Coal Board devised and developed, with the assistance of the Electricitv Commission, a new typc core lifter and a special 26 ft triple tube core barrel, designed to operate in conjunction with it in bad coring conditions.The core lifter, whieh is propped open clear of incoming core during drilling, is activated by fluid impulses generated inside the core barrel. It can be used with double tube barrels when drilling firm rocks whichdo not change diameter by compaction inside the barrel.Softer rocks. such as clayey types, require the use of a rriple tube barrel.Results from testing carried out to date in difficult areas in New South Wales coalfields have shown that greatly improved results can be obtained with the new equipment. Although developed essentially for coaldrilling, the new core lifter and barrel could be adapted to other fields of diamond drilling. Even in areas where no great coring difficulty is encountered the cost advantage deriving from the greatly inereased life of the core lifter and the adaptor in which it is housed could justify its use.

Jan 1, 1967

By M. K. Larson

Proper employment of numerical stress analysis design tools is based on the demonstrated ability of a model to capture key elements of the geologic site model and accurately simulate how these elements interact with a mine design. While these tools have progressed markedly, they are, at heart, a gross simplification of the abundant complexity of a natural setting and its response to mining. A generic deep longwall site model was developed that includes aspects of the geology of deep coal mines in the Wasatch Plateau and Book Cliffs coal fields of Utah. The site model contains a set of common features and observations of how these features typically respond to mining. This site model was the basis for evaluating use of empirical, boundary element and volume element stress analysis tools to analyze the distribution of stress around a deep longwall panel. More specifically, this evaluation examined shifting of stress to panel abutments and gob, distribution of stress in the abutment, and deformation and failure of bridging strata. Measurements of abutment stress changes at two sites in the Wasatch Plateau region were used to illustrate model calibration. Overall, these comparisons highlight the considerable differences between methods. Volume element tools can incorporate considerable detail and have fewer underlying assumptions, but this detail carries a considerable computational cost. Boundary element tools are much more efficient. But this efficiency also comes at a cost of added assumptions. These assumptions were challenged by the presence of a strong sandstone unit in the overburden, leading to boundary element results that depart significantly from volume element results. Empirical rules are the simplest, but are even more burdened by assumptions, many of which are implicit in underlying cases. Insight into the nature and impacts of underlying assumptions in each method is essential to proper use of results in mine design. Disclaimer: The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the National Institute for Occupational Safety and Health

Jan 1, 2009

By Ronald E. Hamilton

"An attempt to review the recent literature on comminution reveals at once that the subject has many ramifications and that the applications are so diverse that there are very few general statements which can be made.It. seems reasonable to start classification on the basis of size of material as Input to the comminution process. However, we find that this can only be done in a very imprecise manner.The initial step of breaking rock from its natural state of very large pieces in geological formations into sizes suitable for processing is accomplished by blasting. This step in the process has not been ex-amined in this project except to note that great changes have been made during the last decade or so in the explosives used, and in the method of handling them. We should determine what effect changes in mining methods can have on the need for crushing.The second step in the process is usually primary crushing, performed by gyratory or jaw crushers. The largest chunk which can be fed to a jaw crusher depends on the size of the machine, and should be larger than the largest fragment produced in the miring process. It is obvious that the larger the crusher, the less care required in mining to en¬sure the absence of rocks too large to be crushed. The optimum size of crusher to minimize overall cost of mining and reduction is not at all obvious, and no information on this point has come to light in this investigation.It is rather generally accepted that size reduction is most efficiently done in small stages, and that different machines have different opti¬mum size ranges of feed. For example, crushers are preferred for sizes above about 1"", rod mills for the range between 1"" and 0.1"", ball mills are preferred from 0.1""down to perhaps 10 microns, and vibratory mills, or jet mills, below 10 microns."

Jan 1, 1976

By Michael Godard, Peter Cleyle

"Suncor Energy’s Project Millennium increased oilsands production capacity by an additional 95,000 barrels per day to its present level of 225,000 barrels per day. This massive venture included an expanded Mine, new Extraction and Upgrading facilities, as well as, steam and utilities infrastructuresIn the Primary Extraction process, removal of the bitumen from the oil sand begins with slurry preparation and is followed by primary , secondary and tertiary separation processes. The final cleaning step of the bitumen froth is the Secondary Extraction process, that removes residual water, mineral and solids to produce a clean diluted bitumen suitable for Upgrader feedstock.This paper will review the flowsheet of the Millennium Primary Extraction facility, from its recent commissioning through the ramp up to design production rates. In addition, new technologies in the Primary Extraction flowsheet will be reviewed.INTRODUCTIONAs conventional supplies of oil and gas are depleted in Canada, the Athabasca oil sands industry of Alberta becomes an increasingly important source of energy. Today, high quality crude from Alberta’s oil sands accounts for roughly 30% of Canada’s daily petroleum production. According to government projections, over the next 7 years, oil sands production is expected to more then double, and by 2010 more than half of Canada’s crude oil is expected to come from the oil sands.Oil sands deposits consist of a layer of sand saturated with bitumen covered by a muskeg overburden and underlain by silt and clay. The oil sand is mined where the overburden is economical to remove, typically less than thirty meters thick. The Athabasca oil sand deposits around Fort McMurrray is ideal for mining. Bitumen can be described as a diverse collection of hydrocarbons, organosulfur, and nitrogen compounds."

Jan 1, 2004

By Thomas M. Barczak

Advancements in support technology have occurred to a large extent because of the demands of the mine operators. Shield supports are no exception. The most notable changes in shield technology in the past decade have been increases in shield capacity and life expectancy, which have increased by a factor of 4 and 7 respectively since the inception of the shield support 25 years ago. The purpose of this paper is to set goals for the future generations of longwall shields. These goals include: (1) 100,000 cycle life expectancy, (2) improved hydraulic diagnostic capability, (3) smart load control with adjustable setting pressure algorithms, (4) composite material design to reduce weight and increase shield width, (5) constant set leg cylinder design, (6) improved joint design to reduce wear and stress, (7) advancements in leg cylinder socket design, and (8) an instrumented shield to measure in-service structural component loading. These design issues will continue to push the envelope in longwall shield technology that has provided the safest and most productive mining system employed in the history of mining. In preparation for this, a historical examination of shield failures is made and recent trends in shield design are evaluated. Design practices to improve structural margins of current designs are also addressed.

By J. M. Mutmansky, C. Lee

"IntroductionRecognition of Coal Workers' Pneumoconiosis (CWP) as a major occupational disease has affected various aspects of the coal mining industry in the United States as well as in almost all major coal producing countries, Regulations related to the control of coal mine dust forced mine operators to modify their mining and ventilation practices. As the coal production record of the last 15 years shows, this had both direct and indirect impacts on the productivity and production costs.To identify the causes of CWP, many research efforts have been made throughout the world. Most of these studies were epidemiological in nature, attempting to pinpoint exposure and seam variables that affected the incidence of the disease. Other studies have been oriented toward the elemental and mineralogical composition of the coal dust in the mine atmosphere and in the miners' lungs. These studies indicate that there may exist some relationships between the characteristics of the coal mine dust and the prevalence of the disease. Some of the variables that are thought to affect the occurrence of CWP are the mass of the dust in the working place, the rank of the coal, the existence of certain trace elements, the free silica content of the coal, and the existence of other minerals in the respirable dust. A more complete description of these previous research studies has appeared elsewhere (Mutmansky and Lee, 1984).The behavior of particles in the human lung is known to be governed by their aerodynamic diameter, which is defined as the diameter of a hypothetical spherical particle with unit density that exhibits the same settling velocity as the given particle. Because of this fact, the aerodynamic size distribution of coal mine dust is one of the parameters to be determined along with the other physical, elemental, and mineralogical characteristics. The objective of this paper is to establish a strategy for providing coal mine respirable dust samples for characterization purposes using instruments that classify according to the aerodynamic diameter. In addition, several findings concerning characterization methods will be presented"

Mar 1, 1989

By Mazin Adnan

The 80m high dam at the Peribonka river in the Canadian province of Quebec was designed for the generation of 385 MW of hydro electrical power (Fig.1). The complex ground conditions required the employment of a variety of geotechnical construction methods stretched to limits never experienced before. Innovative grouting and trenching techniques were used for the construction of a plastic concrete cut-off wall down to a depth of about 116m, to cut hydraulic seepage through alluvial deposits forming the dam foundation. The bedrock where the cut-off wall is embedded forms a glacial gully with steeply sloped flanks, which created further challenging conditions. [ ]

Jan 1, 2008

By Alexsandro Marcio da Silva

Com o objetivo de prover informações precisas, coesas e em tempo real aos gestores da Diretoria da Usina Presidente Vargas (UPV) para a tomada de decisões, foi criado o projeto para Gestão de Indicadores de Desempenho em Tempo Real com o foco no processo produtivo e performance das áreas de Laminação (a quente e a frio), Zincagem e Folhas Metálicas. O projeto foi desenvolvido em fases, onde cada fase contemplava um determinado número de equipamentos, áreas e plantas, com visualização em drill down. Utilizando os conceitos de Data Visualization e Operational Intelligence, foi possível integrar e centralizar as informações de diversas fontes de dados, tais como, PIMS, MES, LIMS, ERP, Supervisórios, PROCOM's e entradas manuais. Padronizar as informações de controle do processo produtivo entre os gestores facilita a identificação de problemas e suas causas, e permite analisar simultaneamente várias áreas e plantas. Exibir em tempo real perdas operacionais em decorrência de desvios de processo, torna o processo de tomada de decisão mais rápido e assertivo, contribuindo para a melhoria da performance dos equipamentos, redução de riscos de falhas, e além disso aumenta a vida útil dos equipamentos e otimiza a monitoração dos processos.

Jul 30, 2018