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By C. S. Vender

Knife River Coal Mining Company's Beulah Mine is a multiple seam lignite operation located in western North Dakota. The mine began production in 1963 with annual production at 450,000 metric ton and now produces 2.2 mm ton. As development progresses, operations have advanced into more complex geologic areas. Various techniques have been analyzed to maximize coal recovery in a cost effective manner. Additional studies are on-going to determine what changes will be implemented as we encounter deep wet sands in the reserve area.

Jan 1, 1991

By S. Whinery

In these times of sharp rivalry, both as to price and quality, among the makers and venders of engineering explosives, it is often desirable to be able to determine the relative energy or value of the various explosives offered for sale, in order to purchase intelligently ; or, having contracted for a large amount of an explosive of a certain standard quality, to be able to ascertain if the manufacturer keeps his product up to the specified standard. The simple and inexpensive apparatus described below was devised by the writer while engaged on the improvement of the Tennessee River, at MuscleShoals, under the direction of' Major W. R. King, U. S. Engineers, in the summer of 1879. It answered the purpose so well that it is thought that a brief account of it may be of interest to other engineers. It consisted, essentially, of an old blacksmith's anvil and a common striking hammer, such as is used for driving rock-drills. The anvil was placed face downward on solid, level ground. In what was then the top of it, a vertical hole, one and one-fourth inch in diameter and about one arid three-fourths inch deep, was made with a ratchetdrill. The surface of the anvil immediately around the drill-hole was made as true and smooth as possible with a file. Next, a new striking-hammer, weighing nine pounds, with a turned and true face, was selected ; and a handle, eleven feet long and about one and a half inches in diameter, was fitted into it so that it

Jan 1, 1886

By Carl S. Vender

Knife River Coal Mining Co.'s Beulah Mine is a multiple-seam lignite operation located in western North Dakota. The mine began production in 1963 with annual production of 450 kt (496,000 st). It now produces 2.2 Mt/a (2.4 million stpy). As development progresses, operations advanced into more complex geologic areas. Various techniques have been analyzed to maximize coal recovery in a cost-effective manner. Additional studies are ongoing to determine what changes will be implemented as deep, wet sands are encountered in the reserve area. Knife River Coal began as an underground operation in 1924 at Beulah, 120 km (75 miles) northwest of Bismarck. In 1950, the operation converted to a combination underground and surface mine. The underground segment was closed in 1952. Development of the existing reserve area south of Beulah began in 1963. About one-fourth of the acreage under permit (Fig. 1) is sufficient for 10 years at current production rates.

Jan 1, 1991

By D. B. Hobbs, H. O. Burrows, T. D. Stay

ALUMINUM which has lost its original identity as to source may be considered as secondary. This would include scrap originating in the fabrication of aluminum, which is not consumed at the plant of fabrication, and all material resulting from fabrication, which has lost its original identity regardless of whether it be consumed at the plant of fabrication or not. In general, secondary aluminum may be divided into two classes, commercially pure and alloyed. The chief impurities found in commercially pure aluminum are copper, iron, titanium and silicon; while in aluminum alloys, copper, iron, titanium, silicon, zinc, manganese, magnesium, nickel, or tin, may be present in varying proportions. Occasionally lead and antimony are found in secondary aluminum alloys, especially if the alloy results from remelting vender's automotive scrap. Such alloyed elements as are found in the scrap cannot be removed on remelting. In this, the remelting of secondary aluminum differs from the smelting of secondary copper or most other secondary metals. The majority of secondary materials reach the consumer in the form of remelt ingot or remelt No. 12 ingot. This ingot varies greatly in quality, depending upon the source of the material, and the manner in which it is refined and blended. The principal differences between primary and secondary ingot are: 1. The composition of secondary ingot may be more or less indefinite. 2. Secondary ingot may contain more dross and oxide. Secondary ingot may, however, be used successfully in a great many products. RELATION OF PRIMARY PRODUCTION TO SECONDARY PRODUCTION Table 1, compiled from data published by The American Metal Market, gives an approximate idea of the relation of primary to secondary production. Information obtained from other sources leads the authors to believe that the figures for secondary production are somewhat low.

Jan 1, 1928

By D. B. Hobbs, H. O. Burrows, T. D. Stay

Aluminum which has lost its original identity as to source may be considered as secondary. This would include scrap originating in the fabrication of aluminum, which is not consumed at the plant of fabrication, and all material resulting from fabrication, which has lost its original identity regardless of whether it be consumed at the plant of fabrication or not. In general, secondary aluminum may be divided into two classes, commercially pure and alloyed. The chief impurities found in commercially pure aluminum are copper, iron, titanium and silicon; while in aluminum alloys, copper, iron, titanium, silicon, zinc, manganese, magnesium, nickel, or tin, may be present in varying proportions. Occasionally lead and antimony are found in secondary aluminurn alloys, especially if the alloy results from remelting vender's automotive scrap. Such alloyed elements as are found in the scrap cannot be removed on remelting. In this, the remelting of secondary aluminum differs from the smelting of secondary copper or most other secondary metals. The majority of secondary materials reach the consumer in the form of remelt ingot or remelt No. 12 ingot. This ingot varies greatly in quality, depending upon the source of the material, and the manner in which it is refined and blended. The principal differences between primary and secondary ingot are: 1. The composition of secondary ingot may be more or less inclcfinite. 2. Secondary ingot may contain more dross and oxide. Secondary ingot may, however, be used successfully in a great itiany products. Relation of Primary Production to Secondary Production Table 1, compiled from data published by The Ameriran Metal Market, gives an approxirnatc idea of the relation of primary to srcondary production. Information obtained from other sources leads the authors to believe that the figures for secondary production are somewhat low.

More than 400 academic, government, and industry representatives attended the second symposium on ash utilization and technology held in Pittsburgh, Pa., March 10-11, 1970. Sponsored by the National Coal Association, Edison electric Institute, American Public Power Association, National Ash Association, and the Bureau of Mines, the symposium featured 23 formal presentations by leading experts from Europe and the United States on all major phases of ash production, utilization, and research. Abstracts of all the papers are grouped right after this introduction, and the full symposium proceedings follow. Biographical sketches of the representatives are given in an appendix. Sponsoring organizations and their chief representatives were the National Coal Association, James R. Garvey, Bituminous Coal Research, Inc.; Edison Electric Institute, C. E. Brackett, Southern Electric Generating Co.; American Public Power Association, Howard J. Stemm, Columbus (Ohio) Electricity Division; National Ash Association, Inc., John A. Tillinghast, American Electric Power Service Corp.; and the United States Department of the Interior, Bureau of Mines, William L. Crentz.

Jan 1, 1970

By Juan Carlos Ramírez Larizbeascoa

El presente texto revisa el análisis económico realizado durante los años 1978 y 1986 en las minas de tajo abierto como Cuajone, Toquepala. Así, inicialmente se desarrolló el sistema de cortes concéntricos y bloques. Posteriormente en 1983 y 1984 el método fue adaptado por Thomas. Loose, quien desarrolló el sistema de informática y probó los modelos matemáticos de costo por nivel. Finalmente entre los años 1985 y 1986, el método se aplicó en la evaluación y optimización del método Cuajone donde se consideró los ángulos de talud de la mina, ingresos por uno o varios metales que se explotan, los egresos generados por las operaciones involucradas en la explotación, la ley de corte y la inclusión de parámetros operacionales en la mina.

Nov 24, 1986

By Ricardo Cortés Arana

El presente texto describe el ausentismo y las relaciones humanas como factores de productividad y equilibrio dentro de la compañía minera Atacocha. La asistencia continua al trabajo asegura la estabilidad del empleo y no altera el ritmo de producción de la planta minera. Por consiguiente, la ausencia inmotivada de un trabajador en la mina, afecta el rendimiento de los demás miembros y a la misma empresa. En cuanto las relaciones humanas, estas deben ser constructivas y basadas en el espíritu de cooperación entre obreros y patrones, así como destacar el conocimiento técnico, interés genuino y personal por las personas que trabajan en ella.

Jul 20, 1960

By Mick Fritz, Gregory Poole

Construction blasting is always challenging when in close proximity to existing structures, but when you are next to a landmark like Sanford Stadium at the University of Georgia it can get intense. Blasting on this project was performed less than 100 feet from students studying in their dorms at Reed Hall. Some shots are only a few feet from the columns on the stadium that hold up the sky boxes where meetings were being held while blasting was being performed. If a shot goes vertical the rocks would go through the floor of the sky boxes.

Jan 1, 2011

By R. E. Grant

THE Cerro de Pasco Railway Co., owned and operated by the Corporation, is a common carrier whose chief functions are transportation of ore and concentrates from the mines at Cerro de Pasco to the smelter in Oroya, and haulage of coal from the coal mines at Goyllarisquisga to the coal washery at Fundicion. Connecting with the Peruvian Central Railway at Oroya, the C. de P. Railway maintains joint, daily freight and passenger service from Lima and the port of Callao to Cerro de Pasco, terminal of the C. de P. main line and gateway to the Huanuco Valley. Extending from Oroya to Cerro de Pasco the main line is a standard-gauge roadbed of 70-lb. rail, 132 km. long with a maximum compensated grade of 2.25 per cent and a curvature of 16°, climbing from an elevation of 12,272 ft. above sea level at Oroya, lowest station on the line, to 14,208 ft. at Cerro de Pasco. The highest point reached by the C. de P. is on the coal branch at Alcacocha where the rails are 14,385 ft. above the sea.

Jan 1, 1945

By Lucio Aguilar

El presente texto señala la evolución de la minería donde se evalúa el marco legal, los precios metales, la bondad económica del proyecto por la riqueza del yacimiento y costo operativo.

Sep 1, 1988

By Juan Francisco Retamozo

Hoy es indispensable que los profesionales de ingeniería de minas se capaciten en gestión y habilidades blandas, para responder adecuadamente a los nuevos retos que plantea el mercado laboral. Como producto de su extensa práctica como ingeniero de minas y coach personal en el sector, el autor desarrolla en este artículo diversos aspectos de interés para aquellos profesionales interesados en acceder a posiciones de liderazgo.

Aug 30, 2020

By Robert Head

El presente texto señala las probables tendencias de la industria cuprífera a lo largo de esta década, donde los pronósticos de una parte se basan en los hechos y datos del pasado, tanto de producción como de consumo. En cuanto la producción futura, ésta se basa sobre disminuciones en minas cuyas reservas se agotan, incrementos de minas en plena vida y minas nuevas o probables que serán llevadas a la producción a través de la década. Como consecuencia de esta posición de adecuado abastecimiento la tendencia a investigar por materiales en sustitución del cobre puede ser reducida. Asimismo, la nueva de producción vendrá de minas más grandes, de baja ley que necesitarán grandes inversiones de capital.

Mar 1, 1971

By J. H. East, D. Harrington

"INTRODUCTION The tremendous expansion of industry during the war and the unprecedented demands for metals and minerals are reflected in the production and use of explosives during that period. The increased use of explosives brought added safety problems to industry because of the necessity of using men as blasters who were not entirely familiar with and some who were totally unfamiliar with the characteristics of some or all of the various explosives. A discussion of the characteristics of the ordinary types of explosives used in: industry should assist in giving a better understanding of the hazards attending their use. Explosives are compounded so they may be used with reasonable safety provided the user understands and follows the procedure recognized as standard safety practice. Short cuts and the failure to understand and use recognized safe practices, as well as the selection of explosives unstited for the work at hand, are all part of the safety problem,The extent to which explosives are used in the United States is shown by a study of the statistics compiled by the Bureau of Mines 4/ regarding them. Some of these statistics are shown below and serve as an indicator of the tremendous number of men engaged in the transportation, storage, and use of explosives. Theme men are exposed to the inherent hazards attending this occupation and they should be familiar with the recognized safe practices relative to explosives."

Sep 1, 1946

By Rogelio Frigerio

Ante el impulso de desarrollo económico de Argentina, surgieron técnicas para atacar su apogeo nacionalista. En ese sentido, el presente texto señala las tácticas de esta lucha oblicua contra el desarrollo nacional, que varían de acuerdo a las circunstancias y diversos campos (petróleo,carbón siderúrgia, química, transporte, automotores).

Nov 1, 1961

By Arnaldo T. León

El presente trabajo plantea una solución al déficit habitacional en los campos mineros para reducir los costos a la empresa y beneficiar económicamente al trabajador, familia y a la región. Esta alternativa de solución implica la participación de la empresa y el trabajador donde la compañía ofrece al trabajador un lote de terreno con los servicios básicos y el empleado a través de sus recursos propios, construye su vivienda. Asímismo, se describen las ventajas que representa para cada parte, como el impacto que ocasiona en el desarrollo regional a partir de la mejora de la infraestructura en los centros vecinos.

Apr 1, 1991

By Alejandre Monge Gordillo

La siguiente investigación describe las generalidades de la administración de grandes empresas como principios alternativos y más seguros que los métodos del empirismo. En este punto, se revisan nuevas perspectivas sobre la economía de empresas, los aportes de Frederick W. Taylor y sus medidas de administración científica, los principios generales del establecimiento industrial, los conceptos de la concentración del esfuerzo en un campo limitado de actividad, los principios sobre el costo productivo, el significado económico de la "standarización" y las etapas del desarrollo de una empresa por F. W. Taylor. Concluyendo que la aplicación del método científico es factible en una operación industria,l dado que aprovecha exactamente los resultados de otras operaciones y retoma el conocimiento de otras áreas para organizar adecuadamente una empresa.

Jul 20, 1955

By Aaron Morales

El presente texto analiza la crisis minera -en tanto remite más que un problema de cotizaciones- y señala el error en el concepto de administración como una de las fuente de esta crisis minera. Así los recursos mineros con que cuenta un Estado debe concebirse con cuidado y trabajar con innovación las proyecciones más tangibles. De otro lado, se plantean soluciones desde la metalurgia y así utilizar con ventaja los recursos naturales del país -particularmente los carbones-.

Jan 1, 1986

By Malu Braga Leal

Este trabalho propõe o controle e monitoramento da corrosão em escapamentos de automóveis pela modelagem e mapeamento termo-fluidodinâmico do escapamento utilizando o programa computacional de análise de volumes finitos ANSYS. A corrosão no escapamento do automóvel é produzida e catalisada pelos gases de combustão do motor que fluem aquecidos pelo escapamento. Ao se propor a utilização de uma rede de sensores ópticos nas regiões mapeadas pelo modelo obtido fluido dinâmico do escapamento do automóvel, tem-se uma ferramenta em tempo real para a visualização das regiões de maior gradiente térmico e mais suscetíveis à corrosão pelos gases de combustão no escapamento. A utilização do mapa termo fluidodinâmico do escapamento pelo programa ANSYS possibilita, assim, um maior controle das condições de corrosão no escapamento de um automóvel e na escolha de materiais mais adequados para a sua produção e funcionamento.

Aug 16, 2017

By H Lieberwirth, M Pfeifer, F Heinicke

HPGRs (high pressure grinding rolls) have been developed within the last decades for energy efficient processing of a wide variety of ores. Special interest has been raised by projects increasing the capacities of processing plants by installing HPGRs prior to ball mills. Bond ball mill tests have been used for decades as a base for ball mill dimensioning in mineral circuits. For final CAPEXOPEX considerations of the processing circuit, one key question is about the level of grinding energy split between HPGR and downstream grinding stages. This is especially interesting if the downstream process comprises multiple grinding stages combined with separation steps. The paper presents investigations on grinding energy consumption, size distribution and microfracturing of HPGR products, which affect the efficiency of the whole comminution and sorting process.

Aug 24, 2022