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By F. Clerf

Blast-furnace practice in France is determined more or less by the character of the ores used. Some French ores are siliceous and others are calcareous, therefore by proper burdening a self-fluxing mix can be used. This is not always done, as, for instance, at the Caen furnaces of the Société Métallurgique de Normandie, where the Soumont ore of Normandy is used, which is a carbonate. This ore is crushed and calcined at the mines, yielding a product that is porous and well sized for blast-furnace consumption. The lines of the Caen furnaces are given in Fig. 1. Originally these furnaces had 16 tuyeres; six are plucked and these tuyeres are set in the lower part of the bosh. Operating data on these furnaces are given in Table 1. Table 1.—Operating Data, Caen Furnaces Kg. Lb. Blast-furnace burden per ton of iron: Soumont ore....................................... 200&2100 (44004650) Limestone...................................... 900-1000 (2000-2200) Basic Bessemer slag (bearing phosphorus).............. 100 (220) Scale.............................................. 35 (77) Manganese ores.................................... Coke.............................................. 1100-1200 (2420-2640) Coke analysis: Ash, per cent............. 9.5 H2O, per cent............. 4.0-10.0 Flue dust (approx.), kg. per metric ton.... 200 (440 lb.) Blast volume, cu. m. per hr.............. 83,000 (49,000 cu. ft. per min.) Preesure, lb............................ 12 Blast heat, deg. C....................... 650 (1200" F.) Top temperature, deg. C................ 250 (445O F.) Top-gas analysis, per cent............... CO2 9.3 CO 30.3 O2 0.3 H2 3.0 Production per 24 hr. about 510 tons. MINETTE ORES The most important ore deposits in France are in the west of Lorraine. They are called the "minette" ores and are of two classes-—siliceous and

Jan 1, 1937

By Marianella Guerrero, Gustavo Loyola

La anisotropía y geoestadística local es una técnica que optimiza los parámetros geoestadísticos involucrados en los modelos basados en variogramas de forma local, lo que garantiza una mejor adecuación entre el modelo geoestadístico y los datos observados. Esta técnica se utiliza para determinar y tener en cuenta los parámetros que varían localmente para abordar las anisotropías no estacionarias y locales, permitiendo centrarse en las particularidades locales de la distribución de las leyes. Esta técnica es útil para mejorar la precisión de los modelos geoestadísticos, ya que permite abordar las anisotropías no estacionarias y locales, lo que resulta en una mejor adecuación entre el modelo y los datos observados.

Sep 29, 2023

By R. H. Nicholas

Shuttle cars have undeniably proved their worth as a means of transporting coal underground; however, several factors have arisen in connection with their possible improvement. This report .discusses the effect of shuttle cars that employ rough-tread and smooth-tread tires on mine roadbed, the amount of dust thrown into suspension by the use of such tire treads, and the service rendered by each type of tire. Involved, also, in this study are observations on the use of different amounts of calcium chloride on the haulageways.

Jan 1, 1949

By Renzo D. Verastegui, T. C. Michael Law, Sitotaw Y. Fantaye, Alfredas Daugiala

"When completed, 520 Park Avenue will amend the Manhattan skyline and be one of the most prestigious high rise towers in New York City. The 52-story condominium building is located on a 60 by 100 feet lot on East 60th Street between Park and Madison Avenues. The geographically complex site is bounded by two fragile 5-story masonry buildings on the east and west, a mid-rise building on the north, and a New York City subway tunnel on the south. To add to this complexity, the ambitious development required 70 to 80 feet of excavation, mostly below groundwater level in highly permeable rock, to accommodate four levels of cellars. The new building also cantilevers 24 feet over a five-story historic building on the east. The limited footprint of the building coupled with large compressive and tensile axial loads, considerable base shear and over-turning moments, and the required deep excavation, presented unique foundation challenges. This paper describes how the challenges were solved with an innovative combination of permanent secant pile walls and drilled shafts.INTRODUCTIONThe project site is located at 45 East 60th Street, on the block bounded by East 61st Street to the north, East 60th Street to the south, Park Avenue to the east, and Madison Avenue to the west. As shown in Fig. 1, the site is surrounded on three sides by buildings sensitive to differential settlement. In addition, a NYCT underground subway structure lies below East 60th Street approximately 13 feet south of the site. The base of the subway structure is approximately 42 feet below the street.The project consisted of constructing a 52-story tall building. A portion of the superstructure cantilevers 24 feet over an adjacent five-story historic building. The underground construction for the new building involved a four-level basement, extending about 60 feet below ground surface. The excavation subgrade is much deeper than both the subway structure and the adjacent shallowly-founded building foundations."

Jan 1, 2016

By D. Tao

Froth flotation is widely used in the coal industry to clean -28 mesh or -100 mesh fine coal. A successful recovery of particles by flotation depends on efficient particle-bubble collision and attachment with minimal subsequent particle detachment from bubble. Flotation is effective in a narrow size range outside which the flotation efficiency drops sharply. A fundamental analysis has shown that use of picobubbles can significantly improve the flotation recovery of particles by increasing the probability of collision and attachment and reducing the probability of detachment. A specially designed column with a picobubble generator has been developed for enhanced recovery of fine coal particles. Picobubbles were produced based on the hydrodynamic cavitation principle. Experimental results with one metallurgical coal and one steam coal have shown that the use of picobubbles in a 2" column flotation increased fine coal recovery by 10-30%, depending on the feed rate, collector dosage, and other flotation conditions. Picobubbles also acted as a secondary collector and reduced the collector dosage by one third to one half.

Jan 1, 2006

By Tatiana Salviano Gadelha

Rejeitos de mineração descartados na forma de polpa possuem, geralmente, grande quantidade de água e reutilizá-la no processo, por meio de operações de desaguamento mais eficientes é de grande importância para a implementação de projetos de menor impacto ambiental. O presente trabalho visa estudar as operações envolvidas no desaguamento de um rejeito de níquel, com o objetivo de principalmente a maximizar a recuperação de água de processo. Para tanto, foram avaliados: a influência da concentração de sólidos, uso e dosagem de floculante, pressão no filtro, o processo de filtração com e sem prensagem e a influência destas variáveis na umidade da torta e na recuperação de água. Os resultados mostraram que quanto maior a dosagem de floculante menor é a recuperação de água na filtragem; por outro lado, quanto maiores a concentração de sólidos e a pressão, maior a recuperação de água. Verificou-se a importância do uso da prensagem para maximizar a recuperação da água contida no sedimento, sendo possível comprovar que o rejeito de níquel floculado e filtrado com ?P de 6 bar com o uso de prensagem promoveu a recuperação de até 77% de água.

Aug 17, 2017

By D. A. Sloan

THE Young Davidson mine is of particular interest because of the extremely low costs and also because of the novel method devised for pillar recovery. The outstanding feature of the mining system is its simplicity and regularity. The successful operation of this property was de-finitely assured by the rise in price of gold in 1934. The mine is situated in the southeastern part of Powell township, about forty-five miles southeast of Timmins, Ontario. The local town, two miles distant, in Matachewan, which is twenty-five miles northwest of Elk Lake, the terminus of a branch line of the Temiskaming and Northern Ontario railway. Mining is confined to one of a group of five claims. The ore occurs in a body of syen.ite porphyry which is intruded along a contact of Timiskaming conglomerates with Keewatin altered ruffs and greenstones. This intrusion extends in a north-easterly direction from Davidson creek for 3,300 feet, of which length 700 feet lies within the Matachewan Consolidated property. The maximum width of the mass is 700 feet; it tapers off as it extends east-ward. The Orebody.-The syenite porphyry is of three types, probably all differentiates of the same magma, but only one of them is gold bearing. This is a cherry-red, coarsely crystalline type which forms the central part of the mass. It is more brittle and more fractured than the others, and consequently has allowed easier access to the gold-bearing solutions. The gold has been brought in by a branching system of quartz veins and along minute fractures. It is mainly in the form of very fine 'free' gold, but also occurs in pyrite, which is the chief metallic mineral.

Jan 1, 1942

By Albert L. Brautigam, Michael C. Leigh, August J. Kwitowski

The U.S. Bureau of Mines developed and tested a teleoperating system to control a new highwall mining system. A remote operator was provided out-of-sight sensory information and control of coal extraction and haulage equipment. Surface and production testing proved that the teleoperating system supplied the operator with sufficient sensory information to operate the mining system. Details on the teleoperating system provided in this report include (1) sensor selection, (2) a description of the electronic control system, (3) equipment selection and modifications, (4) the positive test results, and (5) recommendations for system improvements.

Jan 1, 1992

Research on the Thermodynamics of Siderite Roast Decomposition and the Experiment of Magnetic Roasting-Separation

Sep 13, 2010

By Olaf Andersen

Crucible melt extraction yields short metal fibers with eqivalent diameters as low as 50 µm from almost arbitrary metals and alloys. Highly porous components can be made from such fibers by suitable deposition and sintering methods. This technology is being developed at the Dresden based Department of Powder Metallurgy and Composite Materials of the Fraunhofer Institute for Manufacturing and Advanced Materials (IFAM) and has been applied to gold alloys and iron-base alloys containing small additions of precious metals. From the manufactured gold fibers, sintered structures were made for decorative applications. Additionally, it was found that due to rapid solidification during the fiber formation, precious metals can be finely dispersed in ironchromium- aluminum (FeCrAl) and FeAl20 alloys. Good catalytic activity at elevated temperatures was found in compositions containing 3 wt.-% Ce and 0.5 wt.-% Pt.

Oct 1, 2003

By Miguel Álvarez Uriarte

Como consecuencia de las bajas cotizaciones internacionales que hubo para la fluorita en la primera mitad del decenio de 1960, su producción creció lentamente respecto a los requerimientos del consumo mundial. Dicha escasez se reflejó en una recuperación de los precios y fue suficiente incentivo, junto con otros factores, para que la producción mundial del metaloide aumentará notablemente en 1971. En ese sentido, el presente texto describe el panorama de la fluorita en México a través del Instituto Mexicano de la Fluorita y así obtener información actualizada sobre el mercado y producciones mundiales, la situación de proyectos mineros de fluorita en otros países y sobre el desarrollo y usos de sustitutos de la fluorita.

Nov 1, 1975

By Robert A. Jankowski, J. Drew Potts

The Bureau has identified several ventilation techniques and a water spray application for reducing auger mining dust levels. The dust control methods all work by improving air quantity or flow patterns at the face. Section airflow is maximized by reducing air leakage between entries. Sealing stoppings with brushed- on mortar, containing fiberglass additives, reduces leakage. Heading airflow is maximized by properly installing the brattice curtain and keeping the area between the curtain and rib free from obstructions. The brattice curtains should be hung at least 1.7 m (5.5 ft) from the ribs in 7.9 m (26 ft) wide entries and kept less than 4.6 m (15 ft) from the face. A tight curtain seal is created by using the mine air pressure to force the curtain against the timbers, roof and floor of the mine. Using both a blowing curtain and an exhausting curtain will isolate some face workers from dusty air. The Bureau designed, auger clearer spray system, can be used to force heading air across the active face. Laboratory tests indicate that the auger clearer spray system can increase face velocities by more than 0.5 m/sec (100 ft/min), while using less than 0.13 l/sec (2.0 gal/min) of water.

Jan 1, 1989

By Åke Saudström

An EAF dust sample generated in a scrap based steel mill was treated by a combination of hydro- and pyrometallurgial techniques. The EAF dust contained mainly ferritic spinels forming solid solution phases according to the general chemical formula (MnxZnyFe1-x-y)Fe2O4 and other oxide phases such as ZuO. CaO and Ca2Fe2O5. The EAF dust was first treated by hydrochloric acid leaching at p8=3 which dissolved 63% of the zinc. The pyrometallurgical treatment of the leaching residue was studied using an induction heating system to simulate some important operations of EAF smelting of the residue in combination with steelmaking. The leaching residue was mixed with carbon powder to obtain a mixture with 52.1% ZnFe2O4 and 175% carbon. The mixture, scrap, and slag former were charged together in a crucible and heated to attain a melt temperature around 1650°C. The effects of different amounts of mixture on the zinc balance and iron recovery were examined. Based on the test results, suggestions are made for the EAF recycling procedure of the leaching residue.

Jan 1, 2003

By Freddy Syvertsen

"During the past two years the Association of Norwegian Foundries in Norway has been running a project in evaluation of CAD/CAM systems for foundries.In this work we have had a closer look to the various steps from drawings to the finished castings. On this background we have made a specification of the special needs in the foundry process. The main content of this paper is a presentation of this specification.Some CAD/CAM sytems have been compared with the specification and a summary of the result is presented.In the project we have also had a closer look at some systems where we actually have tried the user interface and some of the possibilities in the systems. In this way we have gained a more detailed knowledge of the systems and we have also got some experience in NC-machining from the systems.IntroductionThe development of CAD/CAM systems has taken place with almost no interaction with the foundry business. This becomes clear when you are having a closer look at the systems. Most of them have not the possibility to describe the complex sculptured surfaces that is often found on castings. The people developing the software, have paid little or no attention to the problems arising when a geometry is going to be transformed for the casting process. Among the problems are the decision of where to place the parting line and to adjust the draft angle. These problems must be solved properly to be able to withdraw the model from the sandmould. In die casting the problems must be solved to be able to get the casting out of the die.In Norway some companies have been developing CAD/CAM systems for several years, with limited interest in foundry problems till 1983. To present the special foundry problems to them a specification of the needs was made that year. Another reason for making this specification, was to compare it with the CAD/CAM systems on the market (1).Design of castingsGeometry transferThe foundries in Norway are small units with almost no design of their own casting products. They are subcontractors receiving paper drawings and limited informations about the product from the mechanical industry both in Norway and in other European countries. This is going to change, and in the future the geometry will be transferred by magnetic tape or by a network of computers."

Jan 1, 1986

"La presente investigación señala los trabajos exploratorios realizados en la superficie del sistema de vetas Santa Úrsula, así como el desarrollo de galerías y cortadas con fines de exploración y profundidad. También se indica el laboreo anterior observado -en tanto superficie como profundidad-, y el laboreo reciente en profundidad. El sistema de vetas Santa Úrsula, ubicado al Sur de las oficinas principales del campamento de las Minas Sucuitambo, Arequipa, comprende dos ramales principales paralelos hacia el NW que se unen hacia el SE, y una serie de ramales secundarios, de escasa potencia, al lado SW, de los principales. Es a partir del afloramiento y el desarrollo de labores en profundidad, que los ramales principales del sistema señalado, ofrecen posibilidades por encima del nivel +40. y se puede revisar el muestreo de todas las labores antiguas para tener un mejor interpretación de los sistemas de veta. "

Jul 20, 1957

By Lee M. Manna

This report summarizes the program to design, fabricate, install and preliminary test a pneumatic braking system for 10-ton mine haulage cars. Major arrangement drawings are reproduced, pneumatic schematics, parts list and actual developed costs. Recommendations as to system improvements are made.

Jan 1, 1977

By Silvana Flores, Nora Flores, Carlos Aliaga, Janet Flores, Edison Zegarra

Financiado por el Programa Nacional de Innovación para la Competitividad y Productividad, este estudio propone la implementación de una tecnología limpia para tratar los activos mineros y pasivos ambientales mineros (PAM) de las relaveras de todas las regiones del país y, específicamente, de la relavera de cerro El Toro, en la región La Libertad. Mediante el método integral de remediación químico activo MRTI-SLFCH se lograron reducir los valores de concentración de metales pesados o parámetros inorgánicos, sometiéndolos a un retratamiento metalúrgico de flotación y/o concentración gravimétrica y adecuándolos a la regulación del Estándar de Calidad Ambiental del Suelo (ECA Suelo). Los relaves detoxificados se convierten en agregados de construcción para fabricar ladrillos ecotecnológicos.

Dec 31, 2017

By V. Rajagopal

Corrosion and abrasion properties of a series of chromium-containing cast iron balls with Cr contents ranging from 0 to 29% was evaluated and compared with austenitic stainless steel and mild steel balls. Marked ball wear tests were performed on artificial ore samples consisting of 95% quartzite with either 5% pyrrhotite or 5% chalcopyrite under a nitrogen or oxygen atmosphere. The electrochemical mechanism was investigated by correlating the corrosive wear with the corrosion currents obtained from potentiodynamic polarization curves under abrasion. An offset in their electrochemical activities was observed somewhere between 16 and 26% Cr. In fact, 26 and 29% Cr cast irons showed an excellent corrosion resistance approaching that of austenitic stainless steel. Flotation recoveries were estimated on a 95% quartzite + 5% pyrrhotite sample ground with various cast iron ball materials under an oxygen or nitrogen atmosphere. Electrochemical results are found to be in good agreement with corrosive wear obtained from marked ball wear test and with flotation results.

Jan 1, 1991

By Herle Rodríguez, Frank Astete

El modelo de “liderazgo por octógonos”, nace de la necesidad de generar una estrategia para visibilizar el liderazgo permanente en terreno de los líderes (caminatas gerenciales) y conocer el nivel de cumplimiento de los indicadores de seguridad y salud en cada una de las áreas. El ícono de los octógonos, tomo de referencia a los utilizados por el Ministerio de salud para identificar el riesgo a la salud de un producto, de la misma forma los octógonos (verde, amarillo y rojo) indican el nivel de cumplimiento e implementación del programa de seguridad y salud en cada una de las áreas. Esto logra un impacto visual por la relación al riesgo y la importancia en el cuidado de las personas.

Sep 29, 2023

PRESIDENT AND DIRECTOR JOHN R. SUMAN HOUSTON, TEXAS PAST PRESIDENTS AND DIRECTORS DONALD B. GILLIES CLEVELAND, OHIO H.- G. MOULTON NEW YORK, N.Y. TREASURER AND DIRECTOR KARL -EILERS SEA CLIFF, N. Y. VICE-PRESIDENTS AND DIRECTORS W. B. HENRY HOUSTON, TEXAS HENRY KRUMB NEW YORK, N. Y. ERIE V. DAVELER , NEW YORK N Y W. M PEIRCE PALMERTON, PA. PAUL D. MERICA NEW YORK, N. Y. LEROY SALSICH DULUTH, MINN.

Jan 1, 1941