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The 1969 Lignite Symposium was held at Grand Forks, N. Dak., on May 1-2, 1969. Cosponsored by the University of North Dakota and the Department of the Interior, Bureau of Mines, the meeting was the fifth in this series. Registrants from many States and Canadian Provinces attended the meeting representing many segments of energy-oriented companies, State and Federal Government, and universities. At 2-year intervals, these symposia provide a common meeting place where recent research and developments in technology and utilization of energy resources with emphasis on solid fuels (lignite) are presented. Proceedings3 of the previous symposia including a Forum held in 1958 have been published.4

Jan 1, 1970

By M. M. Wong

Beryllium possesses attractive properties for use in the nuclear and space fields. Since fused-salt electrorefining can be employed to produce this metal in high-purity form from low-grade or scrap metals, the Bureau of Mines investigated electrorefining of beryllium in electrolytes composed of a LiC1-KC1 eutectic mixture plus varying amounts of BeC12. Results showed a 99- percent or better reduction of oxygen and magnesium and a substantial reduction of other minor metallic impurities. Extremely pure beryllium metal was produced. Operating variables, including BeCl2 concentration in the bath (3.5 to 16.5 mole-percent), temperature of operation (450° to 550° C.), and cathode current density (45 to 770 a,/sq, ft.), were studied; their effects on the deposition of metal, working condition of the bath, and purity of the refined metal are discussed. The safety precautions used in handling beryllium in the laboratory are also described.

Jan 1, 1962

By Turgut Yalcin

"Recent years have seen a resurgence of interest in flotation cell design, and one of the areas where attention is being focused is flotation in centrifugal fields which aims at increasing the flotation rates by forced bubble-particle contact.A new cycloflotation device was developed at Laurentian University and tested on the nickel ore of Falconbridge Limited in Sudbury. In comparison with conventional flotation, cycloflotation yielded at least seven times faster flotation rates in terms of the mass of solids floated per unit time per unit flotation volume, while producing concentrate grades similar to those of conventional flotation. These results, which were obtained with a bench-scale ""cyclofloat cell,"" suggest that cycloflotation has the potential of setting a new direction in flotation technology.IntroductionFroth flotation is no doubt the dominant separation technique in the mineral processing industry. Since its inception early in this century, much research effort has been and is still being expended on this process. Until recent years, emphasis seems to have been placed on the chemical aspects of flotation, but there is now an increased awareness for the need to improve flotation machine performance and more and more attention is being directed towards this area. In a 1982 article on ""Flotation Machines"" (Young 1982) it is stated that "" ... by now the design of the machines used would have reached a high level of perfection, ... In fact, this is not the case ... "".The process of flotation in a flotation device may be considered to take place in several distinct stages as follows:"

Jan 1, 1994

By Xinhua Wang, Qiangqiang Wang, Yubin Li, Shusen Li, Lifeng Zhang

"Numerical simulation on the fluid flow in a Flow-Control Mold (FC-Mold) were performed. The motion of inclusions were calculated. With FC-Mold, the flow pattern and surface velocity become more symmetrical, and at higher casting speed the velocity of liquid steel in the top region of the mold was largely reduced with the highest velocity of the meniscus reducing from 0.65 mis to 0.4 mis, and the meniscus shape became flatter. With FC-Mold, more inclusions approached to the surface of the slab and the amount of inclusion in the center of mold became fewer. Larger inclusions were easier to remove, however, the EM filed of the FC-Mold could hardly improve the removal of inclusions from the molten steel.IntroductionElectromagnetic brake technology is an effective method to control the flow pattern within continuous casting mold, together with other casting parameters, nozzle design and mold geometry [1-5]. Due to the interaction between the applied magnetic flux and the conductive molten steel inside the mold cavity, a force is generated in the direction opposite to the jet flow, which can decelerate the high speed steel jet from the SEN ports. The potential benefits include fewer surface and internal defects, fewer inclusion especially at higher casting speed. However if used imperfectly, electromagnetic forces can have opposite effect [6]. Numerical models are the best tool to optimize electromagnetic flow control. In the current study, numerical simulation was performed to investigate the flow field in a continuous casting FC-Mold, and the effect of different operation parameters on the flow, surface level and velocity in FC-Mold were discussed."

Jan 1, 2013

Esso-BHP have installed a production supervisory control system that is presently controlling the offshore oil and gas facilities on the Barracouta and Marlin platforms from an onshore master station. This control is achieved with a computerized master station onshore which uses a UHF radio system for telemetry and control.The system is designed to control, monitor, and gather data from a large number of oil and gas production platforms and has flexibility to handle future variations in operating conditions.The system will be extended to the Halibut platform late in 1970 and to the Kirlgfish platforms during 1971.

Jan 1, 1971

The beach sand industry is the only Australian mineral industry which, so far, has used electrostatic separation on a full commercial scale. The main application of the process is for the separation of rutile from zircon. Laboratory work has demonstrated that electrostatic methods are effective for ilmenite-monazite and cassiterite-zircon separations, thus facilitating the production of high grade monazite and cassiterite products from top-strip table concentrates, but the commercial application of these processeshas been rather limited so far. Overseas, electrostatic methods are becoming more widely used for the treatment of granular material which is not amenable to flotation. The use of electrostatic separation for the treatment of ores other than beach sands has been investigated in this laboratory 1, 2, 3, and two pilot separators were built during i953 to carry out field tests. Of these, the first was an inclined feed plate separator for the removal of silica from granular lime-sand in Western Australia, the second a conductance roll separator for the removal of diamonds from alluvial gravel in New South Wales. In both cases the whole of the ore passed through the separator, not a gravity concentrate only as in beach sand practice. The two types of separator mentioned are shown diagramatically in Figs. 1 and 2.

Jan 1, 1954

By Zach Ellis, Dusty Fisher

The Office of Surface Mining, Reclamation, and Enforcement (OSM) cited a large surface coal mine for a series of flyrock incidents that occurred when blasting close to the mining lease perimeter. The OSM placed the company on a pattern of violation status. It was determined through analysis of blasting practices that flyrock could be controlled at the mine by drilling a smaller diameter hole and stemming with crushed rock when blasting within 1,000’ (304 m) of the lease line. The procedure to install and remove the small diameter drill steel was cumbersome and dangerous because it was a manual transition. The drill carousel could only hold one diameter at the time the project was initiated. The process was very time consuming, involving a mechanic to transport the steel to the drill and spend up to 1.5 hours of downtime switching the steel. In addition, the hydraulically operated break-out wrench and break-out fork on the SKS Infinity Redrill® is only designed to work with one diameter, so these tools could not be used to disconnect subs and steels on the string. At the time, the mine’s breakdown was between 30-40% small diameter (6 ¾” (171 mm)) versus large diameter drilling (10 5/8” (270 mm)). The drill and blast group was challenged with the task to implement a 6s (Six Sigma) project that would reduce the amount of time spent on steel change-outs on the rotary drills while improving the safety of the task. A solution was proposed to carry the small diameter drill pipe, lower small diameter sub, and small diameter bit on board the drill at all times. The goal of the project was to carry the steel in the carousel after modification so that the driller could change the diameter himself on board the drill in less than 45 minutes without any assistance from a mechanic. The drill had to be modified so that the hydraulic operated break out wrench and deck fork could be utilized on both diameters. The drill accessory supplier and the mine worked together to design and implement design changes and new equipment onto two rotary drills, and new standard operating procedures (SOPs) were created for the new process. The project has been in the sustaining phase for approximately three months now and all steel diameter changes are completed by the operator under the allowable time limit.

Jan 1, 2015

By P. A. Plunkert, D. E. Morse, L. McCartan, J. F. Papp

The mineral sector is a fundamental part of the U.S. economy. It contributes to the real gross domestic product (GDP) at several stages —basic (mining), intermediate processing, manufacturing of finished goods and construction. The real GDP increased by 3.5 percent from 2004 to 2005. The nominal GDP was $12.5 trillion at the end of 2005. Housing starts were up by more than 5 percent for the year, and the unemployment rate decreased to 5.1 percent in 2005 from 5.5 percent in 2004. The prime interest rate increased from 5.25 percent at the beginning of the year to 7.25 percent at the end of the year. The value of minerals mined in the United States in 2005 rose significantly because of increased unit prices for some metals —particularly molybdenum — and significantly increased production for some industrial minerals, mainly cement, construction sand and gravel, and crushed stone.

Jan 1, 2006

By Paramguru R. K, Jena P. K

Increasing demand for copper, lead and zinc with continuous depletion of good grade ore reserves, warrants the need for utilization of lean and complex ores of these metals. There is worldwide effort to develop suitable processes for these purposes. The present paper deals with the chloride leaching of complex base metal sulphide concentrates of two Indian deposits. A two stage leaching process is suggested keeping selectivity of metal dissolution in view.In the first stage most of the lead and zinc are reacted with dilute FeCI3 (0.3M) solutions at a temperature ono°c where major portion of the lead remains in the residue and zinc reports in solution. After taking out lead chloride by brine leaching, the residue has been treated for copper dissolution. A concentrated FeCI3 leaching at boiling temperature as well as ambient aqueous chlorine leaching have been separately tried to dissolve out the copper from the residue. Based on the results obtained, a flowsheet for the proposed process is presented.

Jan 1, 1981

By Fernando Saavedra

En los sectores de mina, concentradora y planta Mofito, perteneciente a la minera Codelco Chuquimata, las redes de control exigen un aumento en los volúmenes de información de control en los equipos de operación y mantenimiento. Por ello, se plantea mejorar la disponiibilidad, confiabilidad y robustez de las redes existentes en las distintas áreas de la minera Chuquimalta a través de un proyecto que optimize dichas condiciones de las redes de control ControlNet Y EtherNet/P y así aumentar la confiabilidad impactando en la disminución de los tiempos de pérdida-producción relacionados con fallas en las redes de control.

Sep 1, 2014

During the last 125 years, the steel industry has witnessed revolutionary changes in the process of steelmaking. The Bessemer process was the predominant steel production technology during the last two decades of the 19th century. The open hearth process accounted for the lion's share of world steel production for six decades from 1910 to 1970. With the appearance of the LD process on the industrial stage in 1952, the importance of open hearth process declined and currently the basic oxygen processes are contributing more than 60 per cent of the world steel production. The LD process also led to the development of several other oxygen blown processes such as LDAC, OLP, OBM, QBOP, EOF, Clc.

Jan 1, 1999

By Aníbal Castañaga Coll

El presente trabajo refiere los resultados de las pruebas sobre el empleo de las membranas filtrantes en la colección y análisis de muestras de polvo. De los resulados, se encontró que las muestras de polvo colectadas con membranas filtrantes para el estudio de su potencialidad silicógena, deben ser disueltas en acetona u otro solvente orgánico, para evitar los errores por defecto a que da lugar la transparencia del cuarzo y otros minerales con índices de refracción próximos al 1. 5 cuando se emplea el método directo. Asimismo, el método de la disolución en acetona se corresponde con los resultados del método Impinger, eliminando el problema creado por la excesiva acumulación de las partículas de polvo en las membranas filtrantes,considerándose como el más adecuado para espacios polvorientos.

Jul 20, 1961

By A. Rubina P.

El presentre trabajo describe las propiedades del mercurio, usos, consumo, precios, reservas de producción, condiciones, así como el proceso que comprende su metalurgia y los factores que intervienen en los hornos rotatorios de la mina Santa Bárbara ciomo la velocidad de los gases, importancia de los refractarios, temperaturas, bafles, control de combustión, refinación y mantenimiento de operación. De otro lado, la Sociedad mineral "El brocal" enfoca el problema de la metalurgia de su mineral de arenisca a partir de la clasificación del mineral en grueso y fino. El primero, será beneficiado en las instalaciones de horno rotatorio, mientras que el fino se tratará a través de la flotación-retortas, flotación-briquetes-horno rotatorio y flotación, lixiviación, electrólisis.

Jul 20, 1960

By Ike Isagon

Outline 1.Background Sudbury Backfill Operations 2.Alternative Binder 3.Alternative Binder Trial Process Flow Diagram ?Laboratory Results ?Plant Trial ?Final Evaluation and Approval ?Management of Change (MOC) 4.Economics 5.Conclusion 6.References and Acknowledgements

Nov 1, 2011

By S. C. Holmes

El presente texto describe las tecnologías empleadas para el proyecto de Safford, Arizona. El proyecto consiste en la explotación de dos minas medianas a tajo abierto de las que se extraerá el mineral de cobre oxidado de baja ley a través de un sistema de materiales. En este sentido, el texto describe la aplicación del grupo de tecnologías ((MTG, por sus siglas en inglés) de Phelps Dodge para mejorar la seguridad, obtener eficiencia en los equipos y reducir los costos operativos de capital .

Mar 1, 2013

By Alex Villanueva, Sheylla Sánchez

Huella Verde, es un proyecto de forestación implementado por Newmont Yanacocha y Foncreagro, organización que desde 1999 implementa proyectos de desarrollo agropecuario y forestal. Esta iniciativa da continuidad a la experiencia implementada entre los años 2000 y 2012, etapa en la que se realizó la plantación de más de 2 millones de árboles de pino y otras especies nativas en Cajamarca.

Sep 29, 2023

By the courtesy of Metropolitana Milanese (Milan Underground), roost of the delegates visited on April 12, 1991 the tunnel of "PORTA VENEZIA" STATION of MILANO RAILWAY LINK. The "PORTA VENEZIA" STATION will be the most important in the link and it will he also the largest underground project of the whole railway transport network in Lomhardy. The particular conditions of the soil and the collocation of site in the center of Milano have required new technologies and the technical solution applied to this job is called "Cellular Arch Method" by its designer Prof. P. Lunardi. Our sincere thanks go to Prof. P. Lunardi and Eng. E.M. Pizzarotti of Rocksoil, Milano who have kindly furnished us a technical description of this method. Eng. Pizzarotti was the guide during the visit and gave all the technical explanations to the delegates. THE "VENEZIA" STATION IN THE 2PB SECTION OF THE RAILWAY LINK The excavation of cavities in loose ground, exceeding a certain dimension and at shallow depth, is not feasible using traditional methods: in fact it is not possible to consolidate the ground around the cavity in such a way that homogeneity and resistance is sufficiently guaranteed.

Jan 1, 1994

By Siegfried Arce

Existen muchas herramientas para la gestión de proyectos. Sin embargo, éstos no están en capacidad de realizar análisis de riesgos y evaluar alternativas que consideren incertidumbre. En ese sentido, aparece GoldSim como una herramienta flexible que a través de una plataforma gráfica, posibilita la simulación probabilística y dinámica de sistemas complejos. Asimismo, permite observar las relaciones entre los diferentes elementos, de forma que nos genera transparencia del modelo preparado, por ende,confianza en el modelo y en sus resultados.

Aug 25, 2002

By J Guo, K Williams, J Y. Guo, A W. Roberts, M Jones, B Chen

Numerical simulations using the discrete element method (DEM) were carried out to investigate the flow patterns and stress field redistribution at the hopper and feeder interface. The influences of different filling heights, belt speeds and clearances between the hopper bottom and feeder surface on feeder loads were studied. Meanwhile, experiments were conducted by utilising wedged plane-flow hoppers with different configurations and horizontal feeders with various clearances. The simulation results were compared with theoretical values and experimental measurements. In terms of the cases presented in this study, simulation results reveal good agreements with experimental observations regarding the flow pattern. Being similar to the theoretical values, the simulations provide close predictions on vertical feeder loads for steady flow states, but they may show significant overestimations for initial states. Additionally, suggestions are given for relevant simulation parameters based on the comparisons shown in this investigation.CITATION:Guo, J, Roberts, A W, Williams, K, Jones, M, Chen, B and Guo, Y J, 2017. Simulation investigation of flow patterns and feeder loads at hopper/feeder interface, in Proceedings Iron Ore 2017, pp 173–182 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By D. F. Malan, Y. Jooste

"SynopsisScattered mining was practised on Kusasalethu Mine (previously Elandsrand Gold Mine) prior to 1998, but at deeper mining levels it was no longer feasible, since it would have resulted in unacceptably high stress levels and energy release rates. Longwall mining was not adopted at these depths as the mine required a more flexible mining method owing to the highly variable grade and the presence of geological structures. A mining method was developed that consisted of dip stabilizing pillars for regional support, as well as bracket pillars to clamp geological structures. A strict sequence of extraction was followed and this, together with the particular layout, was called the ‘sequential grid mining method’. This method addressed two key problems, namely negotiating adverse geology and the erratic grade of the Ventersdorp Contact Reef (VCR) orebody. However, a significant drop in production rates resulted in the need for alternatives and improvements to the original mine design. Modifications to the design were proposed in order to increase production rates, and an investigation to consider the rock engineering implications of these modifications was conducted. The study indicated that the modified method, called the ‘multi-raise mining method’, appears to be feasible and might address some of the production problems that were experienced with the original sequential grid design. An analysis of actual seismic data showed no significant differences between the original sequential grid mining and the implemented multi-raise mining. The numerical modelling of the mining layouts showed slightly higher interim energy release rates (ERRs) and average pillar stress (APS) levels during the extraction process. The final values are nevertheless identical to that of the original sequence. The study also investigated the use of a modelled moment method to analyse future seismic trends. The study illustrated that the expected seismic trends will be very similar for the multi-raise method compared to the original sequential grid mining method. This study is nevertheless considered of a preliminary nature and ongoing monitoring and analysis of seismic data at the mine is required to verify the response of the rock mass to the modified sequence and increased extraction rate. In particular, future work needs to investigate the effect of mining rate (advance rates in individual panels as well as volume of mining in particular raise lines) on the level of seismicity."

Jan 1, 2015