Search Documents

By L. You

Theoretical and analytical analyses of three mitigative measures- plane fitting method, trenching, and tension cable led to the development of a total protection plan to eliminate or reduce damages to the residential structures subjected to surface movements caused by underground longwall mining. The protection plan was applied to twelve residential houses and two external garages. The success rate is overwhelming. This paper describes the methods employed for protection and results of those case studies.

Jan 1, 1986

By John H. Paugh

Hydraulic slurrying and pumpability characteristics of phosphate matrix (ore) have not been quantitatively defined. An elemental triangular diagram analysis of rock/sediment texture is used to classify the nature of the ore; then related to empirical field data of hydraulic pressureand production yardage ratios. This experiment is applied as a geotechnical tool to provide empirical data of ore slurry and pumpability characteristics as key considerations in the design of slurry pipeline systems. A real texture variability maps are developed on a section of land to assist mine engineering planning.

Jan 1, 1981

By William D. Hissem

While much technology has been developed and brought to bear in the area of blasting applications, the foundation work required for success in the muck pile begins with the drilling program.

Jan 1, 1997

By Theodore L. Turner

This Bureau of Mines report describes calcination of kaolinitic clay in a direct-fired 2-1/2- by 24-ft rotary kiln at 750° and 775° C. Methods for preparing kaolin feed materials and characterization of calcined products are discussed. Approximately 99 pct of the alumina in a typical eastern Georgia kaolin was soluble in HC1 after calcination at either 750° or 775° C.

Jan 1, 1982

By Efrén Peña Pino

El presente texto señala la aplicación del sistema SAP en la minería subterránea de Minsur. Este sistema operativo maneja las propiedades y procesos de la Sociedad Minsur, el cual cuenta con tres Centros, dos de los cuales son operativos (San Rafael y Pisco) al margen de la central de administración (Lima) y permite la planificación de todos los recursos de la empresa de manera integral, evitando imprevistos y una mejora de decisiones.

Jul 31, 2003

One of the most important factors leading to the success of a cement plant is its location. A multicriteria decision-making method is used to rank alternative plant locations. The set of criteria is established and corresponding criteria should be established for each case study, although this multicriteria decision-making approach has broader applicability. In this paper, the analytic hierarchy process (AHP) with 5 criteria is used to develop a location evaluation hierarchy for an alumina?cement plant in East Azerbaijan province of Iran. Five alternatives for the plant location are evaluated. The main criteria are transportation, water supply, power supply, fuel supply and land. Other criteria have the same importance as these five alternatives. The alternatives are ranked by a multicriteria method and the best site is proposed. Keywords: plant location; multicriteria decision-making

Jan 1, 2005

?? Intro ?? Mass blast principle ?? LaRonde evolution toward mass blast ?? Overview ?? Mining method ?? Longitudinal ?? LaRonde evolution (2002 to today) ?? Drill and blast design ?? Consumptions and statistics ?? Mucking strategies ?? Case study ?? Examples ?? Conclusion ?? As underground mines extends to greater depths, few questions must be asked: ?? How to: keep operations safe eep operation effective reduce the cost maintain and control the dilution ?? Geomechanic method and practices; significant advances have been observed in the field of: ?? ground support ?? mining sequencing ?? Drilling and blasting; research and development has been less extensive, probably due to the following characteristics: ?? Drill and blast are mainly production-oriented ?? Drilling and blasting are more oriented toward productivity ?? Technology relies heavily on suppliers ?? Highly stressed ground conditions ?? generally help the explosives to break the rock for fragmentation ?? intensify over-breaks or blast-induced

Feb 1, 2008

By Krzysztof Kotwica

The steady demand for rock materials leads not only to on increase in mining but to the need for decreasing the loss of material in the process of exploitation as well. It brings about an increase in using of explosives in open pits and as a result an increase of after blasting gases volume, vibrations, the scattering (dispersion) of stone ect. All these factors affecting the environment lead to the research work for applying the electrohydrodynamic methods both in open casts and underground mines. In the article the authors describe the concept of this method and construction of equipment which recently have been successfully introduced in mining, the results obtained determine the possibilities of using this method and the future directions. The results of combined method with high-pressure water jets cutting and prototype equipment for separating rock blocks from the rock mass using special head with high-pressure water jets are also described.

Jan 1, 2006

By Joner Oliveira Alves

The aim of this work was to study the use of steelmaking slag as raw material to the production of rock wool and glass wool. Firstly, the chemical composition of the slag was analyzed. These results were used to infer the amount of additives to assemble the charge for the experiments. A laboratory-scale electric furnace was used to melt the mixtures used as charge. The melt material were turned into a water filled recipient, this process was performed in order to impose a fast freezing that is a characteristic of mineral wool production. Finally, with the rest of the melt material it was performed the Herty Viscosity Test. Samples of the produced material were characterized by different analyses. The results found in this research may lead to a technological innovation, because they indicate that the use of steelmaking slag to produce rock wool and glass wool is possible.

Jan 1, 2009

By Herbert Cremer

The United States,-the largest nickel consumer in the world, produces virtually no nickel from domestic ores. Dependence upon outside nickel - sources and increasing strategic, importance of nickel focused the attention of the United States on deposits within its boundries. The most likely domestic sources of nickel are low-grade oxide and silicate deposits, such as the Cle Clum deposit, Kittitas County, Wash., and the Riddle deposit, Douglas County, Oreg. The Federal Bureau of Mines, Northwest Electrodevelopment Laboratory, Albany, Oreg. has been investigating electric smelting of low-grade oxide and silicate nickel ores. These smelting studies have been on selective reduction to produce low-carbon ferronickel. Selective reduction is based upon the relative reducibility of: nickel, iron, and chromium, in the order named, when the charge contains insufficient carbon or other reductants to reduce the entire quantity of these metals present in the ore.

Jan 1, 1954

By L. A. Haas

A kinetic study of the carbon deposition reaction was undertaken by the Bureau of Mines as part of a broad investigation of metallurgical reactions in the iron ore blast furnace. The disproportionation of carbon monoxide on iron pellets was investigated at carbon monoxide pressures between 0.5 and 2 atmospheres (absolute) and temperatures from 400° to 1,075° C. Gas flow in the range from 0.25 to 0.85 standard liter per minute was found to have little effect on the reaction velocity. The addition of nitrogen and helium to caron monoxide exerted only a dilution effect on the rate of carbon deposition. However, an addition of 1 percent hydrogen increased the rate about 100 times. Small amounts of carbon dioxide in the inlet gas exerted little effect on the rate of carbon deposition. The maximum rate for carbon deposition in the first 2 hours occurred at 550° C. The apparent molar activation energies at various stages of the reaction were found to vary from 13 kcal initially to 36 kcal during the latter stages of the reaction. The reaction rate behavior was tentatively explained by an adsorption step followed by the diffusion of iron through a shell of inactive iron carbide.

Jan 1, 1968

By David Leidel, James Stuart

The 50 ohm resistorized electric detonator is commonly used in the oilfield for initiation of wireline conveyed perforating guns and other downhole explosive tools. This type of electric detonator provides some degree of safety above that of the conventional one ohm electric detonator, since a higher current level is required to initiate the device. In order to obtain the necessary data to develop safe distance tables from RF sources for the 50 ohm electric detonator, laboratory tests were conducted to determine the detonator’s “no-fire” current, AC impedance, and its susceptibility to ESD. The results were surprising as two types of failure modes were observed. The “no-fire’ current levels determined from Langlie “One-Shot” Test Methods were determined for the devices tested providing values for the 0.999 probability “no-fire” power level at a 95% confidence level. This data will serve as the basis for sets of safe distance tables from RF sources that will appear in the forthcoming edition of the Institute of Makers of Explosives Safety Library Publication 20, “Safety Guide for the Prevention of Radio Frequency Radiation Hazards in the Use of Commercial Electric Detonators, (Blasting Caps)”.

Jan 1, 2010

By Robert Hanson, Mayur K. Patel

"Pneumatic conveying pipelines are used throughout a variety of industries, from food processing/packing to power generation plants, as an efficient means of transporting materials between storage and processing points. In general, different phases of pneumatic conveying exist when material is conveyed from point A to point B in a pipeline. This depends on the operating pressure and the material conveyed. Lean phase conveying exists when pipelines are operated at high airflow rates, relatively low pressures, inducing sufficient turbulence for particles to become entrained in the air stream. Thus, particles are conveyed along the pipelines at velocities in the range of IS-2Sm/s. Generally, the initial capital costs for lean phase system is low, however the running costs are high. The opposite is true for dense phase, high-pressure systems. In considering either conveying system, it is important that the rate of erosion of the pipeline be considered when designing such a system, since it is the rate of erosion that dictates the lifetime of components. In general, the high level of erosion occurs for lean phase flows, where high impact velocity contribute substantially to the rate of erosion as well as other processes such as particle breaking, if the particles are friable. This would lead to poor quality of material, not normally desirable. On a positive note, the process of erosion is used in other applications, which benefits from this process, e.g. abrasive guns.The failure, by puncture, of pneumatic conveyor bends in industry causes several major problems. Two of these are: (a) escape of the conveyed product causing health and dust hazard and (b) repairing and cleaning up after punctures necessitates shutting down conveyors, which will affect the operation ofthe plant, thus reducing profitability.The paper reports on modelling strategy used in the development of a modelling framework and the initial validation phases of the models incorporated within. The modelling framework encompasses Computational Fluid Dynamics (CFD) related engineering tools, based on Eulerian (gas) and Lagrangian (particle) approaches, to represent the two distinct conveyed phases, to represent the erosion process which is used to ascertain the lifetime of conveyor bends."

Jan 1, 2001

Comparison of Industrial Cyanide Destruction Processes

Sep 13, 2010

By P G. Gaylard

The minerals Industry carries out over US$ 2 billion of R&D annually. The R&D is performed at three levels ? in house research facilities; on a one-on-one basis with a research provider; as syndicated (collaborative) research. The key to a successful R&D programme is project selection. It is suggested that at this time of ?bounty? for the minerals industry the research portfolio should contain some ?blue sky? but potentially long term significantly beneficial projects. This said, the projects should align the technical concepts with the business imperatives. AMIRA has found the ?Road Map? concept has assisted in defining areas for R&D. Examples of this methodology using a Copper Road Map developed by AMIRA for the copper producers operating in South America is presented. The benefits derived from syndicated research are also discussed.

Jan 1, 2007

By P. R. Tisot

Structural response and/or deformation was determined for each of four different grade Green River oil shales (27.0-, 34.5-, 45.5-, and 63.5-gal/ton) as they were heated in an inert atmosphere, under constant compressive stress, from ambient to subretorting temperatures; that is, below those required for rapid pyrolysis of the organic matter. Small cores and small columns of confined fragments comprised the test specimens, which were heated, in a specially designed microunit, at a uniform rate either to 725° or to 825° F under three different stress levels, 80, 200, and 325 psi. Structural response of some cores was observed as they were heated in a stress-free environment. The obtained stress-strain-time-temperature relationships provide information regarding the oil shale's yield temperature, yield stress, rate of compressive strain, loss of mechanical strength, and nature of structural deformation. Effects of structural deformation on induced permeability in small columns of fragments are presented. Results indicate that underground retorting of Green River oil shale may be seriously impaired through loss of induced permeability brought about by structural deformation of rich oil shale under the influence of heat and compressive stress.

Jan 1, 1971

By AIME AIME

Report of Committee 24, of the International Association for Testing Materials, presented at the Brussels Congress, 1906. Republished for use at the 94th Meeting of the American Institute of Mining Engineers, New York, N. Y., February, 1908. Discussion by letter is requested by the Secretary of the Institute. The Committee appointed for the solution of Problem 24 consisted of the following members Prof. H. M. Howe, New York, N. Y. (Chairman); L. Levy, Paris, France (Vice-Chairman) ; Prof. D. Tschernoff, St. Petersburg, Russia (Vice-Chairman) ; Prof. Albert Sauveur, Cambridge, Mass. (Secretary) ; Van Drunen, Ixelles, Belgium; Lieut.-Col. H. Tusen, Copenhagen, Denmark ; E. P. Martin, Abergavenny, England ; A. Pourcel, Paris, France ; H. Brauer, Dortmund, Germany ; Dr. Prof. H. Wedding, Berlin, Germany; P. Verole, Milan, Italy ; A. Baalsrud, Christiania, Norway ; A. R. v. Dormus, Vienna, Austria ; A. Sailler, Vienna, Austria; Bureau des Forges, St. Petersburg, Russia; Prof. N. Belelub-sky, St. Petersburg, Russia ; N. Jossa, St. Petersburg, Russia ; Maj.-Gen. M. Korobkoff, St. Petersburg, Russia ; S. Smirnoff, St. Petersburg, Russia ;.Ladislaus v. Tetmajer, Budapest, Hungary ; H. H. Campbell, Steelton, Pa. Early in February, 1905, a list of species and varieties of iron and steel, with definitions, drawn by the Chairman and Secretary of Committee 24, was sent to every member of this Committee with a request for comments and suggestions. A special request was sent to the following gentlemen . for the equivalents in their several languages of these species and varieties : A. , Pourcel, Paris, France; Prof. H. Wedding, Berlin, Germany ; J. A. Brinell, Stockholm, Sweden ; Prof. H. I. Hannover, Copenhagen, Denmark; Prof. P. Kley, Delft, Holland; P. Verole, Milan, Italy; Col. Cubillo, Trubia, Spain. This present report, which is based upon our original list and definitions, and upon the replies to these requests, consists of four parts I. A polyglot, which gives the names of the chief classes of iron and steel in English, French, German, Swedish, Danish and Dutch. We .regret that we have failed to get the Italian and Spanish names. II. English definitions of principal classes of iron and steel. III. A glossary of special sizes and shapes of iron and steel. IV. A note on the boundary between steel and cast-iron. I. POLYGLOT, IN ENGLISH, FRENCH, GERMAN, SWEDISH, DANISH AND DUTCH, OF THE CHIEF CLASSES OF IRON AND STEEL, AND OF THE APPARATUS IN WHICH THEY ARE MADE. This list is not intended to be complete, but rather to include only those varieties which are of interest to the Association.

Mar 1, 1908

By Patrick Pelletier Jr., Pierre-Alexandre Bossé, Gianni Bartolacci, Ian Orford, Steve Parent

"Over the last decades, many authors have shown the importance of froth in the flotation process. Mineral recovery is related to froth recovery and flotation. Selectivity is affected by froth characteristics, especially structure and loading. The characteristics of froth textures could therefore be used for diagnosing flotation.Machine imaging, especially image texture analysis, allows on-line measurement of important froth characteristics and process state classification. The measured characteristics include froth texture, loading and stability indicators. To extract information from images, texture analysis tools are used as well as a block-matching algorithm (BMA). For process state classification, images are analyzed with the same tools and clustering is done with multivariate data analysis algorithms.Two case studies, Brunswick Mine Concentrator Cu/Pb circuit and LaRonde Mine Zn circuit, are presented to show that these indicators may be used for diagnosis and control. The influence of manipulated variables on measured froth features is shown as well as the relationship between froth characteristics, mineral recovery and flotation selectivity.INTRODUCTIONImaging is a way to depict abstract characteristics of a scene or an object; it is often related to other types of scientific observations, chemical component concentrations, for example (Geladi and Grahn, 1996). In this paper, the scene is flotation froth. Imaging can be especially useful in applications where it is difficult to obtain the measurements needed for process analysis – froth flotation, for example."

Jan 1, 2006

By R. A. Cummings

Certain roof shales in coal mines deteriorate upon exposure to the atmosphere, causing difficulties in the mining operations and adding to the cost. This report presents the results of both field investigations, in a West Virginia mine, and laboratory studies on the effects of atmospheric moisture on roof shales. Based on these observations, a conceptual procedure is presented on how shale deterioration might be predicted during exploration, and guidelines are given as to how air tempering or conditioning chambers may be designed to reduce moisture effects. Recommendations for further studies are included. An annotated bibliography of the literature constitutes the second volume.

Jan 1, 1981

WITH the exception of the deposits of the Milburn Cement Co near Dunedin, Wilson's Portland Cement Co., on the Mahurangi River (a short distance north of Auckland), and those of the New Zealand Portland Cement Co., at Limestone Island, the cement. Tesources of New Zealand remain practically undeveloped. The Milburn Company utilizes a mixture of limestone and mud for the manufacture of cement, while Wilson's and the New Zealand Portland Cement companies both have the advantage of a natural cement stock which requires but small additions of highgrade limestone to give the mixture required. The plant and deposits of the New Zealand Portland Cement Co are located in Whangarei Harbour, some six miles from thetownship of Whangarei. The works and dwelling-houses are situated on Limestone Island, which, with an area of 92 acres, and rising to a height of 212 ft., supplies the bulk of the raw material required. In addition to the island, the company possesses a high-grade limestone area of, roughly, four acres, situated on the mainland, 11 miles to the south. A better location for a cement works could not well have been chosen. On the east side of the island there is a deep channel, which never shows less than 18 ft. of water alongside the company's...

Jan 1, 1912