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By O S. Maluleke

In some deposits valuable heavy mineral quality is poor due to increased mineral surface coatings from higher slimes and more competent sand orebodies. Mineral surface coating can include silica or aluminium rich clay minerals and iron based minerals that render the final product quality off-specification, in this case specifically ilmenite and zircon. Conventional physical beneficiation processes such as magnetic separation, electrostatic separation and gravity separation are not able to remove these surface coatings. Surface dependent separation techniques such as electrostatic separators are affected by these coatings which hinders the rejection of non-valuable mineral from product. Attrition scrubbing is the most commonly used technique to reduce surface coatings, using mechanically induced particle to particle interaction, abrasion and shearing.In many cases it is a challenge to measure the surface removal efficiency of these scrubbing units. Elemental analysis techniques (ie X-ray flourescence) (XRF) in a multi mineral environment are unable to measure surface impurity reduction with enough precision. Mineralogical analysis (in this case Qemscan®) has constraints in terms of sample preparation with highly coated particles being plucked out during block polishing. This paper suggests a combination of laboratory separation techniques coupled with elemental analysis to evaluate the surface removal efficiency. Three different types of feed materials were used to analyse the efficiency of surface removal using production attritioner scrubbers. This approach relates the downstream beneficiation plant’s expected performance with that of the attrition scrubber’s scrubbing efficiency.

Oct 5, 2011

By Marco Ojeda, Caio Moreira, Edelink Tinoco

Este documento técnico analiza la viabilidad del uso de un relave minero de la empresa Nexa Resources, cómo componente principal para la producción de cemento. El proyecto contempla dos etapas, en la primera etapa se acondicionan las proporciones de los componentes del relave mediante la flotación para en una segunda etapa hacer el tratamiento térmico del relave acondicionado y así producir el Clinker, que es la materia prima base que se usa para fabricar el cemento.

Sep 29, 2023

By Chikao Nishiwaki

INTRODUCTION The Japanese dependency for mineral raw materials from foreign sources increased rapidly within the 20 years since the Korean war. During this 20 year period Japan has attempted to industrialize and develop her economy while depending mostly on heavy import of nearly all kinds of mineral raw materials. She has fabricated them using energy generated mostly by mineral fuel that are also imported. Fabricated goods are either used domestically to accelerate more fabrication industry or exported after adding more refinement or fabrication. In this paper iron ore as a major raw material for the Iron and Steel industry, three major base metals, copper, zinc and lead, and petroleum as a major energy source have been selected as examples to represent the general features of various kinds of mineral raw materials that are imported. Among other important mineral commodities for which Japan dependa upon foreign sources are: Aluminium, nickel and cobalt, potash and phosphorous 100 percent dependent and tin, tungusten, chromium and molybdenum over 95 percent dependent. IRON ORE Statistics for the important iron and steel raw materials, namely iron ore, coal and scrap iron are shown in Tables 1, 2 and Fig. 1. Iron ore is by far the most important and basic among these three commodities. There has been practically no steel or iron imported as a metal into Japan during this period. Iron ore, including aggregate such as pellets, and metallurgical coal are mostly transported in large ore cargo boats to the port where very efficient port facilities unload them directly at the steel mill site. As a result

Jan 1, 1976

By Pierre Buteau

Peat/ands distribution in Canada is widely spread thoughout the country and corresponds to a wide spectrum of wetland habitats which overlay peat deposits. The development and the evolution ofpeat/ands and peat deposits are closely linked together, since the vegetal remains of the peat deposits originate from the peatland habitats, and the peatland habitats constitute a response to many factors, including the properties of the substrate, which are the peat deposits. Peat/ands are defined as waterlogged terrains where the production of plant materials usually exceeds the rate of decomposition. The underlying peat deposits consists of organic residues associated to peatland vegetation, more or less decomposed, built up and kept under anaerobic conditions. Peat/ands evolution and distribution are determined primarily by climatic factors, but also by the geomorphology and edaphic conditions. All of these create particular hydrodynamical environments which will vary according to different regional settings, and sequentially to an evolutive time frame.

Jan 1, 2001

By E. L. Rawlins

The development of commercial natural-gas reserves in the Michigan stray sandstone horizon of central Michigan during the past few years has resulted in expansion of the natural-gas industry in that State. The location of the natural-gas reserves of Michigan in the general vicinity of domestic and industrial markets is of economic importance, and in supplying these markets with natural gas a reasonable knowledge of, the extent and availability of the reserves is needed in formulating regulations for drilling gas wells and producing natural gas in analyzing the feasibility of projects to construct natural-gas transmission lines, in promoting and developing markets for the domestic and industrial consumption of natural gas, and in solving many engineering and economic problems common to the natural-gas industry. The development of the natural-gas industry in Michigan has been related closely to the development of oil production. The potential oil production of Michigan is comparable with that in most of the eastern oil-producing States. The development of oil production probably will continue, especially in the central Michigan Basin area; and as wells are drilled to deep horizons in the search for oil, more knowledge will be obtained of the gas reserves in formations above the oil-bearing horizons.

Jan 1, 1936

1. Domestic Production and Use: In 1975.12 companies operated 31 primary aluminum reduction plants, with 3 firms accounting for 67% of production capacity. Washington, Oregon, and Montana accounted for 37% of the total production; Gulf Coast States 21%, Northern States 29%, and other Southern States 13%. Output of primary metal in 1975 was valued at $3.0 billion. Aluminum consumption by 25,000 firms was centered in the East Central United States. Of aluminum consuming industries in 1975, building accounted for about 21%; transportation 19%; electrical 14%; packaging 18%; and consumer durables, 9%.

Jan 1, 1976

1. Domestic Production and Use: In 1977, 12 companies operated 31 primary aluminum reduction plants, with 3 firms accounting for 65% of production capacity. Washington, Oregon, and Montana accounted for 31% of the total capacity; Gulf Coast States 23%, Northern States 26%, and other Southern States 20%. Based on estimated producer prices output of primary metal in 1977 Has valued at $4.6 billion. Aluminum consumption by 25,000 firms was centered 'in the East Central United States. Of aluminum consuming industries in 1977, building accounted for about 25%; packaging 22%; transportation 21%; electrical 11%; consumer durables 9%; and other uses, 12%.

Jan 1, 1978

Domestic Production and Use: In 1976, 12 companies operated 31 primary aluminum reduction plants, with 3 firms accounting for 63% of production capacity. Washington, Oregon, and Montana accounted for 36% of the total production; Gulf Coast States 19%, Northern States 29%, and other Southern States 16%. Based on published producer prices output of primary metal in 1976 was valued at $3.8 billion. Aluminum consumption by 25,000 firms was centered in the East Central United States. Of aluminum consuming industries in 1976 building accounted for about 25%; packaging 22%; transportation 19%; electrical 13%; , consumer durables 8%; and other uses, 13%.

Jan 1, 1977

By Hazel J. Stratton

IN THE HALF-CENTURY that has passed since the Bureau of Mines was established in July 1910, the research and technologic investigations conducted by the Bureau's scientists, engineers, and other personnel have helped significantly in improving health and safety in the mineral industries and have contributed substantially in conserving the Nation's mineral resources through improved techniques in the mining, treatment, and use of mineral commodities. From Bureau laboratories have come new materials for industry and better methods of extracting and processing minerals and mineral fuels. Bureau safety investigations-complemented by equipment testing and by programs of mine inspection and education-have brought about safer and more healthful working conditions.

Jan 1, 1960

By James D. Hall

THE Dome ore-bodies are more or less isolated and are mined. by shrinkage stoping. An interwoven system of veins is mined at Hollinger '.1.nd requires close filling. Deep mining is the problem at McIntyre. Dome ore contains a large amount of free gold, which is recovered on blankets. An all-cyanide flow-sheet is \lSed in the Hollinger mill. Flotation concentration is an important feature of McIntyre mill operation. Therefore, these three mines afford an unusual opportunity to compare gold mining and milling methods. The purpose of this paper is to describe the conditions existing at the Dome, Hollinger, and McIntyre mines and to outline the mining and milling practice at each property. Figures 3, 4, 5, and 7 are reproduced from the Canadian Mining ]011rna/, September, 1935 (Young, A. W., Mining at Hollinger), and Figures 8 to 11 from the Engineering and Mining Journal, November, 1933 (Keeley, D. E., Development and Mining at McIntyre). The photographs (Figures 6, 12, and 13) are by The Canadian Government Motion Picture Bureau. Diagrams of the several mill flow-sheets, which formed a part of the original paper, are not reproduced here. They will be found in Dorr's Cyanidation and Concentration of Gold and Silver Ores.

Jan 1, 1938

By Amado Yataco Medina

Año a año el incremento de muertes por ignición del gas metano o carbón en concentraciones mayores a las soportable, se hace cada vez mayor. Por tal motivo, el presente texto refiere la importancia de las normas de control y seguridad, como las factores sobre la explosividad del polvo del carbon. Entre estos tenemos: la distribución de partículas, composición de polvo, el gas inflamable en el aire, cantidad de polvo, distribución de polvo en la mina, fuentes de ignición, rugosidades de la labor y cambio de sección. Existen dos formas de prevenir dichas explosiones: la primera, es a través de la prevención de acumulación de gas por medio de la ventilación y la segunda, es por medio de la eliminación de las posibles causas de la ignición. Asimismo, se sugiere una serie de recomendaciones de prevención de explosión, como se describe los reglamentos del Código de Minería.

Aug 20, 1965

By R. R. Trengove

This paper is one of a series published by the Bureau of Mines on mining methods and operation practices. It describes the open-pit mining method and operations of the Kaiser Steel Corp. Eagle Mountain iron-ore mine, which is in the extreme southeastern part of California 175 miles east of Los Angeles in Riverside County. Nearest town to the mine is Indio, which is 60 miles away by an excellent highway (fig. 1). Elevations at the deposit vary from 1,400 to 3,000 feet. Figure 2 is a plan map of the Eagle Mountain iron mine. Kaiser Steel Corp. built a model camp at the mine, with all modern conveniences (fig. 3). The camp, comprising 145 homes, dormitories, mess hall, commissary, post office, and recreational facilities for 600 people, is at 1,390-foot elevation. The area has winter-resort weather between October and May, with occasional drops of temperature to 25° at night. From June to September temperatures sometimes rise to 1200 during the day. Rainfall is scant, approximately 2 inches a year, the majority of which comes as cloudbursts during the summer months.

Jan 1, 1956

By J. Roger Loebenstein

This report presents a U.S. Bureau of Mines study of the flow of arsenic-containing materials in the United States, based on the best data available in 1991, includes a consideration of arsenic as a byproduct of the processing of nonferrous metals, the fate of arsenic in manufacturing wastes, the quantity of arsenic used in products, tile fate of arsenic in dissipative uses, and the useful life of discarded products. Where possible, estimates are given of the amounts of arsenic lost from the materials flow. Arsenic byproduct of mining nonferrous metals. Historically, most U.S. production has been from the states of Montana, Washington, and Utah. The smelters in these states are believed to be the areas of the country where arsenic is most concentrated in the soil, tailings ponds, and waste dumps. Since the closure of the last domestic producer of arsenic in 1985, all arsenic has been derived from imported sources. Historically, arsenic was important in agricultural applications as an insecticide, herbicide, and cotton desiccant. As the environmental movement gained momentum and the toxicity of arsenic became better understood, most of the agricultural uses for arsenic were banned. Beginning about 1975, the use of arsenic as a wood preservative began to grow. After 1980, wood preservative uses became more important than agricultural applications. By 1990, 70% of the arsenic consumed in the United States was used by the wood preservative industry and 20% by the agricultural industry. The major source of domestic arsenic emissions in 1989 was from the U.S. copper processing indus¬try. About 7,800 mt/yr of arsenic was discarded in leach dumps, tailings, and slag. Another 800 mt/yr was liberated to the atmosphere and 1/100 mt/yr was exported in copper concentrates. On the consumption side, 9,200 mt/yr was lost, mostly from dissipative agricultural uses and the disposal of obsolete arsenical products.

Jan 1, 1994

By R. V. Ramani, A. S. C. Owili-eger

? THIS PROGRAM SIMULATES METHANE FLOWRATES THROUGH THE GOAL ? SEAM BY THE GAUSS-SEIDEL ITERATIVE TECHNIQUE. THE MODEL IS A TWO ? DIMENSIONAL SYSTEM. THE ITERATIVE FORM OF THE GAUSS-SEIDEL IS ? OBTAINED FROM A PARTIAL DIFFERENTIAL EQUATION OF FLOW BY CENTRAL ? FINITE-DIFFERENCING APPROXIMATION SCHEME ? NPRESS IS THE NUMBER OF SPECIFIED PRESSURES EXCLUDING ? RESERVOIR AND FACE PRESSURES ? NQUAN IS THE NUMBER OF SPECIFIED FLOW QUANTITY.... EXCEPT FLOW ? OUT OF THE FACE. THIS- QUANTITY CAN BE POSITIVE(INJECTION) OR ? NEGATIVE ( PRODUCTION) ? XPERM(I,J) I S THE DIRECTIONAL PERMEABILITY IN THE X-DIRECTION AT THE POINT (I,J) ? YPERM(I,J) IS THE DIRECTIONAL PERMEABILITY IN THE Y-DIRECTION ? AT THE POINT (I,J) ? RESEP' IS THE RESERVOIR PRESSURE ? FACEP IS THE FACE PRESSURE. THIS PRESSURE IS ASSUMED TO BE ? APPROXIMATELY ATMOSPHERIC ? LENGTH, WIDTH, AND THICK ARE THE ZONE OR MEDIUM DIMENSIONS * PUHL I S A DUMMY NAME FOR VISCOSITY ? DMAXI IS VARIABLE NAME FOR INITIAL MAXIMUM ERROR OF ITERATION ? DMAXF IS A VARIABLE NAME FOR FINAL MAXIMUM ERROR OF ITERATION ? NITER IS A VARIABLE NAME FOR STORAGE OF NUMBER OF ITERATIONS ? RAD IS A VARIABLE NAME FOR THE SPECTRAL RADIUS OF THE GAUSS¬ ? SEIDEL MATRI-X. THIS PARAMETER ALSO MEASURES THE RATE OF ? CONVERGENCE OF THE ITERATION ? KOUNT IS AN ITERATION COUNTER ? MAXIT IS THE MAXIMUM NUMBER OF ITERATION SPECIFIED BY THE USER # EPS IS THE MAXIMUM RESIDUAL ALLOWABLE ERROR-FOR CONVERGENCE

Jan 1, 1974

By John Soule

The Torpedo copper mine in the Organ Mining, District, Dona Ana County, N. Mex., was discovered in 1899, and production of copper from oxidized-ore deposits was begun in 1900. Production continued through 1907, but operations were only intermittent frown 1907 through 1921. The production of copper during these periods amounted to about 3,500,000 pounds. Reserves primary sulfide copper ore were believed to occur below the old workings, and after a detailed examination of accessible workings and a study of drilling records of several private companies by an engineer of the Bureau of Mines, a development program of diamond core drilling was initiated. This investigation was started October 3, 1949; and completed April 30, 1950. Four holes totaling 2,122.3 feet wore diamond-drilled, and 70 samples were analyzed. All drilling was done with a Government-owned hydraulic-feet drill having special rods and core barrels to increase the recovery of core in critical zones. This report describes the location, history, ore deposits, and factual data obtained by the Bureau of Mines from the drilling.

Jan 1, 1951

By B. D. Nash

The object of this research was to investigate the technical feasibility of preparing chromium metal by the thermal decomposition of bisbenzene chromium. Bisbenzene chromium, a pi-bonded sandwich type organometallic compound, was thermally decomposed under reduced pressure to form a metal plate on a heated substrate. Metal recovery was close to 100 percent of theoretical, with deposition rates up to 20.8 mg/hr/cm2. Metal purity was dependent not only upon the purity of the starting material, but also upon the sublimation rate of bisbenzene chromium. Total detectable metallic impurities ranged from a low of 18 ppm to several hundred ppm. In general, metallic impurities were less than 100 ppm. Carbon, the major nonmetallic impurity, ranged from less than 0.3 percent to more than 10 percent. The carbon contamination is most likely a result of the decomposition of the organic portion of bisbenzene chromium. An unusual property of some of the deposits was their outstanding corrosion resistance. Unlike pure electrolytic chromium, which dissolves readily, these deposits were insoluble in hot mineral acids.

Jan 1, 1968

By J. E. Philpott

El presente trabajo señala una serie de técnicas modernas desarrolladas para lograr un empleo más eficiente del carbón, ya sea referido a su combustión como a su posible conversión en otros productos. Para ello, se evalúan las condiciones desfavorables de las cuencas carboníferas y se observa el desarrollo y progreso en el futuro de las mismas con la aplicación de estas técnicas. Entre los métodos tenemos: la programación in situ, combustión del carbón en lecho fluidizado, las nuevas técnicas para la conversión del carbón y el coque formado y reducción directa del mineral de hierro.

Nov 20, 1978

By Soule&apos, John H.

Although known since 1902, the Capitan iron deposits have not been tined, mainly because of the low grade of the ore. Only a small amount of exploratory work has been done since the discovery. C. H. Johnson, district engineer of the Bureau of Mines in New Mexico in 1942-4, visited the property; as a result, preliminary sampling of the property was done in 1943.2/ Owing to the results of this preliminary work, an extensive development program by wagon drilling was planned and executed early in 1944. Equipment available at that time was limited in the depths that could be reached; and as geologic studies indicated the possibility that other limestone beds below the surface might have been replaced by iron minerals, a supplementary development program by churn drilling to reach greater depths was prosecuted in late 1947 and early 1948, with the author as project engineer.

Jan 1, 1949

By John W. Buch

Hydraulic cutting tests made on samples of Pennsylvania anthracite (3,700 psi and 260 gpm) were promising enough for the Bureau to establish a full scale experiment in an anthracite mine. Water pressure and quantity for mining anthracite were arbitrarily established at 5,000 psi and 300 gpm (1,000 hp). For full-volume flow, hydraulic pressure is controlled by orifice size with the displacement pump. The hydraulic jumbo was designed for maneuvering on pitches from 0° to 20° in any direction and for a coalbed ranging in thickness from 10 feet 6 inches to 15 feet. All motions of the jumbo are by oil hydraulics. Jet flow is controlled (start-stop) at the face, through an interlocked pushbutton system. One button is in the operator's cab; one, at the pump station; and one (a safety shutoff), near the mining face. To December 1962, 7,400 tons of bed material had been mined at an average rate of 0.800 ton per minute, with an average power requirement of 14.125 kilowatt-hours per ton. In January 1963, the objective was changed from an engineering-development basis to a research basis--to determine, ultimately, the most efficient level of operating characteristics for maximum response, as measured by mining-out rate. This research phase of the project is not yet complete, but conclusions, and the method of arriving at them, will be made the subject of another Bureau publication. It should be noted that as of December 1963 nearly 13,000 tons of bed material had been mined, at rates as high as 1. 3 tons per minute for a complete face advance.

Jan 1, 1965

By Pedro Máximo Ángeles

El presente texto señala el proceso «Strategic-Udy Modificado Angeles» utilizado para la producción de fierro o semiacero en Chimbote, Ancash. En ese sentido, durante la producción de aceros, es opcional el uso de fierros secundarios en la fundición (Scrap). La gran flexibilidad que ofrece el proceso permite producir tan bajo tonelaje sin sacrificar el costo de producción por tonelada de metal. Asimismo, las reparaciones pueden hacerse con gran facilidad, quitando la alimentación, drenando el horno eléctrico y cortando la corriente. Se puede operar el tonelaje deseado en una planta ya instalada con un pequeño descenso en la eficiencia. Por ello, es el método más adecuado en los lugares donde no se dispone de coke, tal es el caso de Chimbote - Perú y en donde se dispone de energía eléctrica barata, y de carbones que requieren procesos caros para su coquificación.

Nov 1, 1963