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By C. B. Manula

Bituminous coal mining in the United States is currently experiencing a period of rapid growth which began in the early 1960's. Future demands are conservatively predicted to rise to 700 million tons by 1980 and to anywhere between 1 to 3 billion tons by the turn of the century. This means a continuous expansion of coal production by a factor of at least two can be expected before the end of the century. Over the last few years, production from underground mining has decreased; yet it is about 50% of the total coal output. In the absence of any discovery of near surface coal deposits, and even after conceding that some deeper deposits can be surface mined with changes in technology it can be reasonably assumed that coal production from underground will continue to play an important part in solving the energy crisis.

Jan 1, 1975

By Shklyar FR, Bokovikov BA, Gordon YM, Scherbatskii VB, Yaroshenko YG, Shvydkii VS

The paper presents, for the first time, a complete mathematical model of the flow of gases in packed beds which describes the processes of gas-mechanics in iron blast furnaces and other shaft type smelting units. Good correlation between calculated and experimental results was obtained confirming the adequacy of the model. It is shown that the uniformity of gas distribution is related to the tuyere size and the extent of its protrusion into the furnace and that these variables may be used to regulate gas distribution across the furnace diameter. It is also concluded that furnace height has no significant influence on gas distribution. The necessity for a mathematical description of raceway phenomena has been experimentally proved. Conclusions from theory are shown to have profound implication to furnace design and operation.

Jan 1, 1975

By Ovchinnikov YN, Novikov VS, Spirin NA, Babushkin NM, Mysik AF, Shcherbatskii VB, Kukarkin AS

Laboratory investigations were carried out to determine the resistance coefficient of the flow through beds irrigated with wetting and non-wetting liquids. A formula was obtained which may be used to evaluate the resistance of the irrigated packing. Quantitative investigations were also carried out on operating furnaces at Magnitogorsk. Continuous measurements of the lower pressure drops were made under different furnace conditions. Pressures were measured in the tuyere space and the bosh region. A significant transient behaviour of the pressure drop was observed in the irrigated zone as a function of the accumulation of the liquid phase in the bosh region as smelting progressed. Additionally, transient processes were also investigated in the upper furnace zones. The basic cause of the transient behaviour was shown to be the irregularity of burden descent caused by the casting cycle. It was shown that the rate of burden descent between consecutive casts reflects fairly accurately the accumulation and drainage of the liquid products as a result of which heat transfer, reduction and aerodynamic processes assume transient character. In practically all cases of casting a decrease in blast pressure and that over the furnace height of 0.2 kg/cm2 was observed. The analyses of radial gas composition at the stock line showed that compositional variations connected with the casting cycle are most pronounced in the central and peripheral regions, whilst in the intermediate regions the conditions are relatively stable. Calculations show that as casting progresses there is a decrease in the gas flow rate at the periphery and an increase in the centre of the furnace. The transient nature of the aerodynamic processes in packings revealed the existence of an appreciable reserve capacity. Elimination of transience was tested on the furnace at Magnitogorsk and improved operating and economical furnace parameters obtained.

Jan 1, 1975

By O. J. C. Runnalls

Canada has played a significant role in the international uranium industry for some three decades. Although there have been many challenges in the past, the future offers a more extensive range of problems and prospects as Canada moves to expand its activities in all aspects of the nuclear fuel cycle. World uranium demand could grow to an annual requirement of 500,000 tons U308 by the year 2000. A substantial fraction of this material is likely to come from Canada because the country's reserves and resources are large, and because of a favourable geological potential for future discoveries. There has been a long history of association between the producing industry and the federal government, and it has provided the foundation for existing national uranium policies. Close industry-government association will be maintained and developed in future because of the anticipated rapid growth of the industry and the consequent need for continual refinement of government policies relating to exploration, mining, processing and export of uranium.

Jan 1, 1975

By Jack E. Bailey

From a start in 1957, milling 3,000 TPD of copper ore, the Cyprus Pima Mining Company, which is located 20 miles south of Tucson, has expanded its operations four times, and is currently treating over 55,000 TPD of ore.1 The most recent expansion added a 14,000 TPD semi-autogenous concentrator to the operation. Shortly after startup in January, 1972, the semi -autogenous plant exceeded the designed tonnage rate.2 Ore from the mine is delivered to a 54 inch gyratory crusher and is reduced to a minus 8 inch product. From the crusher the ore is stacked on a surge pile and then reclaimed and fed to the two parallel grinding circuits. A 28 ft. diameter by 12 ft. long semi-autogenous mill and a 16.5 ft. diameter by 19 ft. long ball mill make up each grinding circuit. The semi-autogenous mills are in closed circuit with screens and the ball mill circuits are closed with hydro- cyclones. Rougher flotation follows the grinding operation. Concentrate regrinding and cleaner flotation is performed in Mill I, the older mill. The generalized flowsheet is shown in Figure 1.

Jan 1, 1975

A knowledge of the mechanics of wave propagation through the earth is essential if reliable communication systems are to be designed for coal mine environments. To obtain a reliable basis from which accurate propagation predictions could be drawn, a series of theoretical studies have been prepared for the US Bureau of Mines by Mr. Ramsay Decker of Spectra Associates, Inc. through a subcontract with Collins Radio Group. These reports formulate the analytical techniques from which we may derive frequencies and antenna configurations that yield the optimum signal-to-noise ratios over the greatest distances in mine environments. The reports of sections 2 and 4 deal with analytical techniques for determining the signal-to- noise ratio within a mine environment for loop-to-loop and line source-to-loop antenna con- figurations. The analytical results of these reports were then implemented into computer programs to obtain predictions concerning through-the-earth signal propagation. These preliminary predictions are based on noise data compiled by Bensema, Maxwell and Stone, and WVU prior to the extensive research conducted by the National Bureau of Standards (NBS). These initial measurements indicated a 20- to 30-dB lower noise level than that measured recently by NBS. The recent NBS data is that used by Collins in the final predictions. The following outline indicates the order and subject matter treated in the subsequent sections: Section 2 - Signal-to-Noise Analysis for Loop-to-Loop Mine Communications Section 3 - The Horizontal Electric Dipole Section 4 - Signal-to-Noise Analysis for Down-Link Line Source Mine Communications Section 5 - LF Communication Section 6 - The Application of Recent NBS Noise Data to Mine Communications Section 7 - Analysis of Mine Communication Propagation Programs

Nov 15, 1974

A working understanding of present coal mine communications equipment and its usage is an essential prerequisite to the determination of future communications systems needs. As a means of gaining this understanding, a field survey program was planned and implemented. The plan formulated called for obtaining both qualitative and quantitative data from three main areas of interest: the types, physical condition, and performance characteristics of equipment presently used in the sample of mines to be visited; the relationship present communications has to safety and productivity; and the practical, future communications needs as de- rived through interviews with present mine management. In compliance with the original plan, the type and physical condition of equipment in use was found through at-mine interviews of personnel responsible for installation and maintenance. Further evaluation was made through the review of equipment instruction books and maintenance manuals and through in-mine inspection of communications equipment and signal distribution networks. The performance characteristics were determined through listening to conversations and noise levels and by talk-testing from randomly selected stations throughout each mine. System operation was evaluated by asking communication system users their opinions and by noting any difficulties personnel had using the systems. Plans in the second area of interest--that of relating communications to mining operations-- were to observe mining operations and usage of communications; to gain insight through interviews with mine management, from mine superintendents to section foreman; and to look for correlation between communications, production, and safety. Lastly the communication systems needs and requirements were determined from first hand interviews of mine personnel, from the analysis that lead to the individual reports on the eight mines, and from an overview of all of the mines studied. The latter was done to find commonality between the needs of the individual mines such that system requirements having the greatest universal value could be derived, thus lowering per-mine cost of equipment through economics of scale. Armed with tape recorders, backgrounds in communications technology, and with an interview questionnaire that was improved as experience was gained, engineers visited the eight mines to obtain the raw data from which the needs and requirements could be developed through analysis. During the first part of the program two days were spent at each mine so that interviews and tours could be completed, and so that full eight hour shift phone usage recordings could be obtained for statistical analysis. One day visits were sufficient for those trips where tape recordings were not made. During the later trips less attention was given to the statistical nature of communications, and more to how communications relates to the total mining operation.

Nov 15, 1974

This report is a compilation of all information obtained in accordance with the requirements of contracts SO122076 and H0232056. A series of eight coal mines were visited to determine their communications usage and requirements. Presently available equipment was surveyed and evaluated to determine its applicability to the needs of the mines. The equipment studied includes that made by the following companies : Anaconda Telecommunications Division Andrew Antenna Bendix Communications Division Collins Radio Group of Rockwell International Executone Communication and Sound Systems Gau-tronics Mine Safety Appliances Company Motorola Communications and Electronics, Inc National Mine Service Company Plessey Communications Systems Corp Pye Electronics Limited Reach Electronics Set Com Corporation Sonex Incorporated Mine visits and in-depth interviews were made alt the following sites: Robena No. 4, Pennsylvania Greenwich Colliery Mines, Pennsylvania Somerset Coal Mine, Colorado Keystone No. 1, West Virginia Harris Mine No. 1, West Virginia Baldwin Underground No. 1 Mine, Illinois Lovilia No. 4 Coal Mine, Iowa Orient No. 3 Coal Mine, Illinois

Nov 15, 1974

By Peter F. Strong, Robert L. Lagace, Alfred G. Exslie

The theoretical study of WF radio communication in coal mines, with particular reference to the rate of loss of signal strength along a tunnel, and from one tunnel to another around a comer is the concern of this paper. Of prime interest are the nature of the propagation mechanism and the prediction of the radio frequency that propagates with the smallest loss. The theoretical results are compared with published measurements. This work was part of an investigation of new ways to reach and extend two-way communications to the key individuals who are highly mobile within the sections and haulageways of coal mines.

Nov 14, 1974

By David Ballón

El presente texto señala los factores que intervienen en la política minera del Perú , las cuales deben diseñarse de conformidad con los requerimientos y características de cada país. Los principios fundamentales que definen la política minera son: la actividad empresarial del estado en la industria minera, comercialización, refinación, explotación, exploración y la investigación científica y tecnológica, la participación del estado con capitales privados.

Nov 1, 1974

By Luis Briceño Arata

El presente texto señala las posibilidades de evolución cuantitativa de la producción minera del país hasta el año 2000. Para ello, se evaluaron los factores que influyen en la producción, la metolodología de proyección adoptada y así elaborar la producción de elementos estudiados.

Nov 1, 1974

By Daniel Rodríguez Hoyle

El presente artículo describe el proyecto minero Cuajone que comprende prospección, exploración, desarrollo del yacimiento, planeamiento, financiación, construcción y puesta en operación de las instalaciones necesarias para la explotación de la mina.

Nov 1, 1974

By Augusto Weberbauer

El presente texto revisa la geografía e hidrografía del Perú. El territorio peruano forma parte de dos sectores fundamentales del continente sudamericano: los Andes y las Llanuras Bajas del Oriente. Asimismo, nuestra geografía se divide en tres zonas, una occidental, otra media y otra oriental, denominándolas respectivamente: Costa, Sierra y Selva. Las llanuras y colinas de ambos lados, el del Océano Pacífico y el de Amazonía, pertenecen a la "Costa" y "Montaña" respectivamente, en las que se encuentran las partes inferiores de las zonas andinas. Dentro del sistema de los Andes tenemos : Los Andes del Titicaca y de las mesetas volcánicas, los Andes del Apurímac, los Andes del Alto Marañón, Los Andes del Chamaya. En el sector Occidental tenemos la cuenca de Titicaca y Cordilleras orientales y el Nudo de Vilcanota. De otro lado, dentro de las condiciones orográficas e hidrográficas se divide la Costa en cinco partes: de Arica a Pisco, Pisco a Trujillo, Trujillo a la Punta Pariñas, la Punta Pariñas a Tumbes y de Tumbes a Zarumilla.

Sep 1, 1974

By Noel Díaz Bernal

El presente texto señala las concentaciones de metales preciosos, oro y plata dentro de las menas comunes de metales básicos de plomo y zinc en vetas dentro de volcánicos terciarios.

Sep 1, 1974

By Juan Mendoza Mendoza Marsano

La primera actividad minera organizada en el Perú es el laboreo de oro de placeres, cuyo apogeo se ubicó en la provincia de Carabaya, Sandia(Puno) y Quispicanchis(Cusco) en el sur-oriente del país. En ese sentido, el presente trabajo describe los antecedentes históricos de dicha actividad durante la Colonia, la labor del banco minero, los logros del programa y el plan nacional de fomento a la minería.

Sep 1, 1974

By Mario Samamé Boggio

El presente texto describe un concepto sobre la futurología o la ciencia que estudia el desenvolvimiento de la civilización en su proyección hacia el futuro y su relación con la actividad minera. Así también se revisa cómo se constituye la Sociedad Anónima y con ella el germen del sistema capitalista en minería. De otro lado, se describen los recursos mineros y el rol de de la ciencia y tecnología aplicados en el continuo perfeccionamiento de sus métodos y así obtener suficientes materias que satisfagan las demandas de los sistemas puestos en funcionamiento.

Sep 1, 1974

By Marcin Borecki

Una de las condiciones para aumentar los efectos económicos y la seguridad del trabajo consiste en la mejora de la preparación de los licenciados de escuelas mineras, la profundización de sus conocimientos de especialidades determinadas, la introducción de disciplinas básicas para el trabajo en la industria minera y el perfeccionamiento permanente del sobrestante en servicio. En ese sentido, el presente texto señala el uso de métodos analíticos y operacionales que se adecúen al modelo tecnológico y moderno a través del empleo de la técnica electrónica de cálculo, de forma que ayude a tomar decisiones óptimas en el proceso de gestión.

Jul 1, 1974

By Alan Shakespeare

El presente texto desarrolla los aspectos económicos de las miniplantas siderúrgicas de Brasil, las materías primas, ubicación, transporte, dimensiones de la planta, tipos de productos, mano de obra y el capital de costo de las miniplantas siderúrgicas.

Jul 1, 1974

By Alberto Benavides

El presente texto señala la problemática de la educación universitaria en los estudiantes de Ingeniería de Minas -particularmente de la Pontificia Universidad Católica Santa María, donde se busca la integración de materias como geología, mineralogía, concentración de minerales. Asimismo, se desea desarrollar plenamente los yacimientos minerales cuya explotación se les encarga, de forma que se capitalize al máximo en beneficio de la comunidad, de la cual forma parte la empresa. De otro lado, se debe reducir la carga académica en los alumnos, -especialmente en el curso de Matemáticas a través de la eliminación del Análisis Matemático como requisito para los ingenieros de minas. El curso comprende Integración múltiple, Análisis vectorial, Sistemas de ecuaciones diferenciales, Series de Fourier y Análisis numéricos. Asimismo, se busca la implementación de cursos como " "Actualización de Conocimientos", Estadística Aplicada a la Minería y un curso sobre Comercialización de Minerales

Jul 1, 1974

By Jack Robert Miller

El presente artículo analiza el interés de la industria siderúrgica por el mineral de fierro metalizado. Para ello se prevee una rápida elevación en la demanda de materiales ferríferos directamente reducidos por un notable aumento en las actividades siderúrgicas en los próximos 10 a 15 años. La demanda de tales cantidades de acero generará una mayor necesidad de materias primas: mineral de fierro, arrabio, chatarra, carbón coquizable, combustibles y energía, que en casi todos los casos apoyan la necesidad de emplear mineral de fierro directamente reducido. En ese sentido, el perfeccionamiento oportuno de una técnica de pre-reducción de amplia aplicación resulta importante y esencial.

May 1, 1974