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By William J. McDonough

Advanced materials are polymers, metals, and ceramics fabricated as intermaterial compounds, alloys, or composites. The resultant components have higher strength-to-density ratios, greater hardness and wear resistance, and one or more superior thermal, electrical, or optical properties when compared with traditional materials. Advanced materials, the basis for many of today's emerging technologies, offer savings in total energy consumption, improved performance at reasonable cost, and less dependence on imports of strategic and critical mineral resources.

Jan 1, 1992

The efficiency of water sprays in suppressing airborne colliery dust depends on many variable factors. A survey of previous work in this field shows that swirl spray nozzles are the best dust suppressors.Investigations carried out in an experimental dust chamber show that, in spite of limitations to the application of water sprays in underground use, promising dust suppression efficiencies in mechanised mining can be obtained with swirl spray nozzles.INTRODUCTIONA dust hazard has always been associated with coal mining, and the recent growth of mechanisation has resulted in a greater production of fine coal and dust, thus increasing the hazard. A better knowledge and appreciation of the medical aspects and dust explosion factors has led to practices reducing the seriousness of the problem. However, the dust hazard still exists and its control is basically an engineering problem.Dust, as with any atmospheric pollution, may be removed from the, mine by ventilation, which is an indirect method of control. Direct methods, in which the dust is prevented from being produced and from becoming airborne, should be employed where possible. Of these direct methods the most significant is the use of water sprays.THE DUST HAZARDAn appreciation of the physical nature of the more important dust hazards is necessary before considering the removal of the hazard. The main hazards associated with colliery dusts are the health hazard and the explosion hazard. "Dust" comprises solid particles of size minus 20 mesh Tyler (833 microns).

Jan 1, 1964

By José N. De Piérola C

Qda. Honda es una pequeña quebrada ubicada en la vertiente occidental sur del Perú que aporta agua no regulada a las operaciones de la unidad mineraToquepala de Southern Perú. Sin embargo, durante la temporada de lluvia se arrastra material sólido en suspensión y de fondo, inhabilitando las estructuras de captación y limitando su captación de la cuenca. En ese sentido, el presente texto desarrolla una alternativa para modificar la captación de la cuenca - en tanto permita incrementar el flujo captable en periodo húmedo hasta los 110 L/s, a través de un sistema novedoso de filtración adicional al de ventana superficial; y en periodo seco, se disminuya el flujo captado por medio de un escurrimiento aguas abajo de 20 L/s. De forma que desarrolla una distribución ajustada al comportamiento natural del cauce y ambos usuarios se benefician de una fuente muy errática y limitada.

Sep 14, 2009

These proceedings consist of papers presented at Bureau of Mines Technology Transfer Seminars in August 1983 for the purpose of disseminating recent advances in mining technology in the area of large mobile surface mining equipment safety and health. The Bureau of Mines conducts several of these seminars each year in order to bring the latest results of Bureau research to the attention of the mining industry as quickly as possible.

Jan 1, 1983

By B. P. Nutter, M. Lebourg, J. A. McAlister

The Multi-Flow Evaluator (MFE) is a new system of tools providing an original approach in drill-stem testing. It improves control during the testing operation and gives a more accurate evaluation of the fluid recovered while providing additional pressure information for reservoir analysis. The tools are operated entirely by up and down motion of the drill stem. This up and down operation provides a positive means of control and offers easily observed surface indications of tool operating position. An unlimited number of shut-in and flow periods may be taken with this tool while in the hole. The key to the success of the MFE system of tools is the safety seal packer. Until this development, operation of the tools by up and down motion only had proven unreliable. The success ratio of the MFE now exceeds the ratio achieved by conventional tools. The equipment includes a 2,750-cc chamber in which a representative sample of the flowing formation fluid is trapped at the end of the last flow period and brought to the surface under pressure. The sample can be evaluated at the wellsite or transferred under pressure for laboratory analysis. The sampling feature of the tool allows a sample to be obtained from a reservoir which has suffered minimum influence from production. A representative sample can be obtained for laboratory or empirical analysis by employing a testing technique to minimize drawdown during flow periods. Interpretation methods to take advantage of this additional information are presented and supported by actual field examples. INTRODUCTlON The Multi-Flow Evaluator (MFE) represents the most recent technical advance in formation testing. Drill-stem testing techniques prior to the MFE have been limited in three areas—(1) operaiion, (2) recovery analysis, and (3) reservoir analysis. The tools in the MFE system allow maximum control during testing and provide test information superior to that obtainable with conventional tools. The system of tools and the operation procedures are described to illustrate the mechanical advantages over present tools. Methods of pressure build-up and fluid

Jan 1, 1966

"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 José Vergara, José Espinoza

El objetivo principal de la técnica de precorte es generar un plano de debilidad que permita disminuir las vibraciones y gases producidos por las voladuras de producción, de modo que la calidad final del talud no sea vea deteriorada. Mientras que los modelos teóricos suponen limitaciones para diseñar la tronadura para el caso de un macizo rocoso fracturado, los modelos numéricos, aun cuando son complejos en su arquitectura, son una gran herramienta para analizar el comportamiento dinámico que se genera dentro del macizo rocoso al momento de desarrollar la detonación de los explosivos. Este trabajo tiene como objetivo mostrar los resultados obtenidos al aplicar programación en elementos finitos con programa Elfen, en diseños de precorte en roca fracturada.

Sep 20, 2019

By Alejandra Díaz Valdiviezo

En las últimas décadas, la minería no metálica tuvo un crecimiento contínuo y progresivo en todo el mundo. En ese sentido, el presente texto describe la Matriz de usos y aplicaciones como herramienta virtual que busca difundir de forma rápida, actualizada y la información geológica y económica relacionada con las RMI. Esta matriz visualiza las ocurrencias y canteras distribuidas en el territorio por sustancias, regiones, provincias y cuadrángulos que indican los usos y empleos en los principales sectores económicos del país, constituyéndose en el nexo entre productores mineros, industriales, inversionistas en general.

May 1, 2013

Real economic growth for the year will most likely exceed the Administration's estimate of 3.2%, up from 2.9% in 1986, unless consumers change their spending patterns more than expected as a result of the October stock market decline. The economy grew at a real annual rate of 3.7% in the first three quarters of the year, Analysts agree that the stock market decline will slow economic growth-- most have lowered their growth expectations for 1988 by about 1%; but few would argue that the economy will slow significantly in the fourth quarter of 1987. [ ] During this economic recovery, personal consumption expenditures provided the main impetus for growth and a deeping trade deficit, the main hindrance to growth. In 1987, however, personal consumption expenditures grew at a lower rate than the overall economy. Mush of the economic growth resulted from a reduced trade deficit and growing investment by business in equipment to improve productivity and to meet the domestic and foreign demand for products. The declining value of the dollar resulted in a better competitive position for U.S. goods but also contributed to a rising rate of inflation as imports rose in price. Inflation, as measured by the fixed-weighted index for gross national product, was still far below the rates in the early 1980k, however. More than 2 million jobs were created during the year, predominantly in the service sectors of the economy, and the monthly unemployment rate in September fell to the lowest level in a decade. Then, after 13 months of decline, the unemployment rate edged up 0.1 percentage point to 5.9% in October.

Jan 1, 1987

By H. C. Fowler

Technical developments in the American petroleum industry as regards exploration, drilling, production, and transportation were characterized by many anomalous conditions during the half decade 1914-19. A review of the literature of that period discloses the striking fact that individual geologists, engineers, and other technologists were surprisingly well versed concerning the occurrence of natural hydrocarbons and methods of extracting them and were acquainted with many of the physical and chemical characteristics that influence the behavior of fluids in natural reservoirs. However, the industry as a whole knew little of the correct application of recognized fundamentals; indeed, judged by present standards certain expediencies of self-styled "practical' operators seem cumbersome, if not evidences of ignorance.

Jan 1, 1941

By Forrest T. Moyer

[The safety record of the nonmetal mining industry during 1965 way worse than that of 1961 in all general measures s of injury experience except for a slight improvement in the number and frequency rate of nonfatal injuries Work fatalities in 1965 totaled al and occurred .it a frequencyrate of 0.29 and a severity rate of 1,711 per million man-hours of worktime. The fatality total was seven oven higher than to 1964 and the injury ratess increased d 32 and 28 present, respectively Thin total. of 2,172 nonmetal injuries u- in 1965 was 3.4 less than in 1964 and the frequency rate per million ion man-hours worked declined percent to 22.73 from: 23.14 in 1964. However, the 1965 nonfatal severity rate of 1,339 per million man-hours worked was 15 percent our the: d.96,1 rate of 1,160, This increases was largely attributable to two more permanent total and nine more permanent partial injuries. in 1965 than in the proceeding year. The average severity all injuries in 1965 was 132 days, 1-I. or charged per injury or 25 days more than in 1961. Injury experience in the nonmetal mining industry, including and excluding officeworkers, for the a-year period 1961-65 is shown in table 1. The average number of men working, on active days in 1963 was 48,429, or 635 fewer than in 1961. However, mines and mills, wore active an average: of 5 days more for a total of 277 in 1965, and each worker averaged 2,245 hours compared to 2', 190 hours in 1961. As a result, aggregate worktime of 108.7 million man-hours increased 1 percent over the 1964 total of 107.4 million hours.]

Jan 1, 1970

By Enrique Solari

"El presente texto describe el trabajo de las minas de plata, oro y cobre durante la Pre-historia en Chile. En Hauntajaya y Yabricoya los indios trabajaron el cloruro de plata o plata córnea y la plata nativa. Sin embargo, los atacameños y diaguitas, fueron los únicos habitantes prehistóricos que practicaron la metalurgia, aunque no utilizaron el fierro en ninguna de sus formas, debido a su alto punto de fusión. Asimismo, en los primeros cateos o prospecciones que realizaron los indios, buscaban rocas y minerales, tales como la arcilla, el cuarzo, la cuarcita, el sílex, el lapislázuli, la obsidiana, la calcedonia, el jaspe, el ágata, el pedernal y los trabajaron con un gran conocimiento empírico de clivaje para la confección de herramientas y adorno. El método usado en la prospección de minerales fue a través del color, cobre, verde siticatado llamado por los indígenas 'Tanca"" y el carbonato de cobre (malaquita- azurita) llamado por los españoles como ""cardenillo"". Asimismo, los cateadores de minas prehistóricas contribuyeron en el norte de Chile, -en tanto bagaje de conocimientos- de los cuales, los cateadores hasta la época de la República, se sirvieron a la gran aventura de los derroteros de minas. "

Mar 1, 1967

Real economic growth for 1988 may fall short of the 3.3% projected by the Department of Commerce in August 1988 because the summer drought and intense heat in many areas curtailed output more severely than expected. The economy grew at an average annual rate of 3.0% for the first three quarters of the year, slowing in the second and third quarters. Export growth, which occurred even as the dollar edged up compared with other industrial country currencies, was an important factor in the expansion. Notable gains were posted in sales of machinery, computers, aircraft, chemicals, and telecommunications equipment. Imports increased, but not as much as exports, and the U.S. trade position was still much improved from that of 1987. Personal consumption expenditures grew slightly faster than the economy as a whole. Purchases of consumer durables showed notable strength in the first half of 1988, but slowed down in the third quarter. Despite the moderate rise in interest rates, business spending for new plant and equipment also rose and contributed to 1988 gross national product (GNP) growth. Both new business investment and export demand spurred orders for U.S.-made machine tools. Orders for machine tools for the first 8 months of 1988 were almost triple those in the corresponding period in 1987.

Jan 1, 1989

By G. S. Scott

Safety problems in the mining and allied industries have led the Bureau of Mines to investigate over a period of years; the flammability (explosibility) of many types of combustible atmospheres principally at ordinary pressure; the results of these investigations have been made available as a bulletin. However, more recently, the demand for information on the flammability of gaseous mixtures at high and low pressures has increased greatly. In particular, the rapid development of high-altitude aviation has brought demands for information on the flammable (or explosive) characteristics of certain gases and liquids at low pressures. The present report gives the results of about 900 tests made to determine the flammability of the lighter paraffin hydrocarbons mixed with air and nitrogen at pressures of 400 200, 100 and 70 ram. Hg. The gases tested include natural gas, methane, ethane, propane normal butane and isobutane. The minimum pressures at which these gases are capable of propagating flame whorl individually mixed with air also were investigated.

Jan 1, 1952

By Edwin Uribe

La Compañía minera Raura es un yacimiento tipo skarn de zinc, plomo, cobre y plata que tiene un solo halo metasomático explotado (Complejo Catuva), además de cuerpos distales de reemplazamiento, vetas y bolsonadas. En ese sentido, los estudios geoquímicos y geológicos a través de la magnetometría y polarización inducida señalan una mayor visión del yacimiento para la búsqueda de nuevos recursos que permitan un enfoque de minería con mayores volúmenes de producción a menores costos y valores de mineral por tonelada. Así también, se ha logrado encontrar un nuevo halo de skarn mineralizado llamado “Franja Hada– Farallón” y una nueva estructura tipo mantiforme llamada “Manto Nadine”, las cuales posibilitan diseñar métodos de explotación masivos tipo taladros largos y pensar en piques de extracción en Raura.

Feb 1, 2014

By Esteban Chumpitaz, Miguel Pacoticona, Ricardo Huancaya

El sistema cuenta con una alarma audible dentro de la cabina del camión que alerta al conductor en caso que el sistema detecte una condición de somnolencia. La información es almacenada en la base de datos y explotada gracias a los reportes que el sistema brinda, dichos reportes permiten identificar cuáles son los horarios en los cuales se da mayor incidencia de somnolencia, así como el récord por operador y por empresa. La instalación del sistema ha resultado bastante sencilla debido a que los componentes se concentran en un solo dispositivo que es la cámara Kinect, esta cámara consolida diferentes sensores en un solo dispositivo permitiendo su fácil instalación y adaptación por parte del operador. La implementación del presente sistema mantiene una excelente relación costo beneficio, ya que la inversión a realizar es mínima y el beneficio que se obtiene es bastante importante.

Sep 1, 2017

By M. A. Schellhardt

In recent years development of instruments and equipment for determining subsurface pressures and temperatures in. gas and oil wells has made it feasible to obtain information that eras not available in the past on many gas-production problems. The material presented in this report illustrates particularly the value of subsurface-temperature data in the study of subsurface leakage from gas wells. An abnormal decline in the shut-in pressure of the Lone Star Gasoline Co. A. Jones No. 1 gas well in the southern part of the Buffalo (Tex.) field was observed during an interval when a negligible volume of gas bras being withdrawn from the reservoir. Wellhead-pressure readings indicated that the shut-in pressure of the well declined from 2,295 pounds per square inch gage on February 3, 1937, to. 1,445 on February 12, 1935. Tests conducted by engineers of the Lone Star Gas Co. suggested that the subnormal pressure gaged on February 12, 1938, probably was not caused by a head of liquid in the well.

Jan 1, 1940

During the period January 1, 1977 through July 31, 1977, 5 percent (264,000 tons) of U.S. capacity was closed due to power curtailments in the Pacific Northwest because of the shortage of water. During July, one plant in Tennessee cut production by 50,000 tons annually due to a power reduction by the Tennessee Valley Authority. Full capacity production was resumed at a West Virginia smelter during September. If demand for aluminum is strong it seems likely that aluminum supply during the remainder of 1977 and in 1978 will be tight. The price was increased 3¢ per pound to 51¢ per pound effective March 28, 1977, and by an additional 2¢ per pound to 53¢ per pound, effective July 5, 1977. New projects and expansion of existing facilities are planned by Australian aluminum companies over the next 2 to 3 years. The companies listed have committed themselves to spending approximately A$801 million: Alcoa of Australia Ltd. -New alumina plant at Wagerup, south of Perth. Darling Ranges bauxite is located near the proposed project. A$650 million. Coma 1 co Industries Pty. Ltd. -Increase bauxite mining capacity and upgrade or replace other facilities at its Weipa mines on Cape York Peninsula region of Northern Queensland. A$81 million. Alcan Australia Ltd. -Expansion program that will increase capacity of the Kurri Kurri aluminum smelter north of Sydney about 50 percent, and improvement of other facilities at the plant. A$70 million.

Jan 1, 1977

By S. Garcia, J. Gebhardt, D. McBride, A. Hernandez, A. Esplín, M. Cross

The Minera Yanacocha operation consists of several heaps interconnected with ponds and gold recovery plants and presents various operating challenges. A comprehensive process model has been developed in order to better understand the effects of certain operating parameters and inventory issues. An integral component of the process water/mass balance is a model of each heap that describes heap behavior based on the individual characteristics of the heap. The heap models are linked to a mass balancing program in order to track flows and concentrations throughout the circuit. A case study of the process heap model is presented for the La Quinua heap, including results for the normal base line operation and several operational problems such as loss of solution flow to the heap (i.e., pump failure), increased flow to a section of the heap (i.e., pond volume control), effect of significant rain events, and impact of a change in material properties (i.e., change in ore type). The impact on heap operating efficiency is discussed with regard to effects on recovery and gold solution grades.

Jan 1, 2007

By Carlos Rabanal, Levi Guzmán

El éxito del proceso de conminución, desde la trituración hasta la molienda, se centra en la relación entre el consumo de energía y el tamaño de partícula producido. La metodología optimizante propuesta por el autor —y desarrollada por Molycop— provee soluciones integrales para diferentes circuitos de molienda-clasificación, las cuales se traducen en mayores tonelajes de mineral procesado, óptimos consumos de medios de molienda, incrementos en la eficiencia energética y de clasificación y otros beneficios tangibles para las operaciones.

Sep 30, 2020