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By Adam Powell, Matthew Earlam

INFINIUM, Inc. is scaling up a new molten salt electrolysis process for producing rare earth metals. Instead of conventional carbon anodes, this process uses Pure Oxygen Anodes™ which employ a stabilized zirconia solid electrolyte between the molten salt and anode. This eliminates two problems with today's rare earth metal production technology. First, it eliminates carbon anodes and contamination of the product by carbon and its impurities, enabling 10-100 times larger batch size than current practice, and lower labor costs. Second, it eliminates emissions of perfluorocarbons (PFC) such as CF4 and C2F6, which are very problematic greenhouse gases with 6000+ times the global warming potential of CO2. The zirconia also enables a sealed vessel with no LiF emissions, creates a reducing environment enabling use of low-cost welded steel vessels, and either produces a high-purity oxygen by-product or can use natural gas to reduce the necessary electrical energy with no HF production. This paper will describe the technology and its current status for rare earth metal production.

Jan 1, 2014

By G. Azimi, K. K. Varanasi1, A. T. Paxson, R. Dhiman, H. -M. Kwon

Hydrophobic materials that are robust to harsh environments are needed in a broad range of applications. Although durable materials such as metals and ceramics, which are generally hydrophilic, can be rendered hydrophobic by polymeric modifiers, these materials deteriorate in harsh environments. Here it is shown that a class of ceramics comprising the entire lanthanide oxide series, ranging from ceria to lutecia, is intrinsically hydrophobic. Their hydrophobicity is attributed to their unique electronic structure, which inhibits hydrogen bonding with interfacial water molecules. In addition, this work demonstrates that these ceramics sustain hydrophobicity even after exposure to high-temperature environment (1000 °C for 2 h in air). It is envisioned that this class of robust hydrophobic materials will have far-reaching technological potential in various industrial applications, where water repellency and dropwise condensation are desirable.

Jan 1, 2014

By A. Felber

El presente texto señala los aportes del Politécnico o Instituto de Tecnología de Israel para el desarrollo del mismo país. El Politécnico es la única institución israelí que capacita a ingenieros y tecnólogos, arquitectos, urbanistas, y que realiza investigaciones en estos campos de la ciencia. En ese sentido, las necesidades del país fueron los factores que determinaron el programa del Politécnico - en tanto la colonización exigía tanto el avenamiento de los pantanos, la bonificación del suelo, la instalación de agua corriente y la construcción de carreteras, como también que se construyesen edificios y se tendiese en acueductos.

Nov 1, 1962

By Luis Artola

El presente trabajo describe los principales elementos de la gerencia de proyectos que aseguran la calidad de los servicios de consultoría brindados al sector minero. La calidad del servicio de consultoría dependerá del grado de madurez e integración en que se implementen los factores críticos de éxito. Uno de los factores más importantes, es la implementación de metodologías que aseguren procesos confiables, estándares y maduros. En ese sentido, se aplicará la metodología descrita en la guía del PMBOK, así como la de dos buenas prácticas consideradas críticas en el desarrollo del proyecto como son: la aplicación de valor ganado en el control y seguimiento del proyecto y la implementación de un sistema de gestión de riesgos para el proyecto que proteja sus objetivos a través de una gestión consistente y eficaz de la incertidumbre.

Sep 14, 2009

R. C. BUCKETT (Lake View and Star Limited) : At the outset I should like to add my congratulations to those already extended to Mr..Norwood on his excellent paper, which has given us all an inspiration to strive further to improve our plant recoveries. In some respects this paper has left us so little to discuss without considerable time spent on. further research work. At all points one is met by a baffling array of facts which leave one feeling hesitant to speak.The careful and methodical way in which Mr. Norwood went along step by step until all channels of research presenting themselves were tested to his own satisfaction leaves me with but a few comments to make. Particularly striking to me is the explanation of the residual gold values in calcines by recrystallization of haematite and here is a line to be attacked by future studies. This will be mentioned again later.Particularizing on the paper, the first point that struck me was the method of change of pyrite through to the final haematite. I have never been able to satisfy myself that a sample taken from various positions along a roaster when cooled, as described on p. 397, represented a fair sample of the conditions at that point, but I must confess that I have not found a substitute that did satisfy me.However, the following figures are illuminating... But to fill dry a receptacle of known volume with calcines, as described by Mr. Norwood, gives the following apparentspecific gravities:

Jan 1, 1940

By Wilmer McInnis

MOLYBDENUM, one of the more versatile alloying elements in modern metallurgy, was first isolated by Hjelm in 1782. The pure metal is silvery white and softer than steel. It melts at a higher temperature than all other metals except rhenium, tungsten, and tantalum. Molybdenum, a member of group V of the periodic table, chemically exhibits valences in stable compounds of 2, 3, 4, 5, and 6. It is a strong carbide-forming element, and much of its alloying effect in steel is imparted through the formation of carbides. Molybdenum occurs in nature only in combination with other elements. The most common occurence is molybdenite (MoS2), which is widely distributed throughout the world; the few known commercial deposits are the major sources of molybdenun1. The other commercially important mineral, wulfenite (PbMo04), was a major source of molybdenum in the United States during the early part of the 20th century, but with exploration and development of the world-famous Climax molybdenite deposit during the World War of 1914-18, molybdenite soon became the world's major source of molybdenum. In recent years, virtually no wulfenite has been mined. Many copper deposits contain minute percentages of molybdenite; and, since the inauguration during the early 1930's of the recovery of molybdenite as a byproduct of these deposits, they have been an important source of molybdenum.

Jan 1, 1957

This report is in fulfillment of Contract H0230031 awarded to Bituminous Coal Research, Inc., on May 23, 1973. The scope of work to be performed under this contract was divided into four phases: Phase I - Design, Phase II - Construction, Phase III - Field Demonstration, and Phase IV - Analysis and Final Report. During Phase I, an agreement was finalized with the Rochester and Pittsburgh Coal Co. for conducting field tests of the proposed shearer spray systems on a longwall panel in the company's Jane Mine in Indiana County, Pa. A drum was then designed which could be used on the Eickhoff shearer, Model EW170-L, being used on this longwall and which would utilize the following spray systems: 1. One spray nozzle located in front of each cutter bit with the jet directed at the cutting surface. 2. One spray nozzle located in back of each cutter bit with the jet directed at the back of the bit. 3. Standard Eickhoff nozzles located in a header along the drum scrolls. 4. A fixed header mounted on the shearer directly behind the drum to simulate the spray system originally used on the Eickhoff shearer.

Jan 1, 1976

By John D. Rockaway

Failure of the mine floor supporting coal pillars frequently occurs when the subcoal strata include "underclays" or other low strength strata. The failure process has been studied to define the response of these materials to applied coal pillar loads and to determine the applicability of bearing capacity analysis to evaluate unsafe conditions. The study has been accomplished through an investigation of both the intact and insitu geotechnical properties of the subcoal strata and through the installation of floor movement monitoring instrumentation. The results of these studies have indicated that both the shear strength of the underclay and the stratigraphy of the subcoal strata must be considered in the analysis. The shear strength was the major controlling factor determining the ultimate load carrying ability of the materials, but the thickness and stratigraphic position of the weak layers influenced the mechanism of the failure process. The methods of bearing capacity analysis were used to define pillar stability that included provisions for taking into consideration a two-layer system. Conditions assumed for a coal mine where a weak underclay overlies firmer strata. The results of the analysis compared very well with observed mine conditions, indicating marginal conditions in areas of the mine which later experienced pillar support failure. In addition, a "heave factor" was derived to predict potentially unstable floor conditions in the mines studied in detail.

Jan 1, 1979

By Mario Alejandro Bendezú

Este trabajo tiene como objetivo mostrar la importancia de la minería junior en la creación de nuevas minas, así como en el mercado de valores. Este documento tocará los retos por los que está atravesando el sector junior, y analizará las acciones, factores, estrategias y documentos públicos provistos por ciertas mineras junior que lograron llegar a su objetivo. En el primer capítulo de esta tesis se abarcará los conceptos esenciales para poder conocer la minería junior en el cual se precisarán definiciones tale como la de éxito, valor y objetivos que buscan alcanzar este tipo de empresas. En el segundo capítulo se analizará cómo la minería junior ha contribuido en la exploración minera a nivel global. De la misma manera, se identificarán los principales desafíos que están impidiendo que las mineras junior continúen con sus operaciones exploratorias normalmente. El tercer capítulo tiene como finalidad realizar el estudio y análisis de aquellas mineras que llegaron al éxito, para realizar esto se ha recopilado toda la información relevante que puede haber contribuido a que la minera junior analizada haya cumplido su objetivo. Por último, se presentaran una serie de ratios, estrategias y variables extraídos del análisis de las mineras junior exitosas para poder identificar a las actuales junior que están encaminadas al éxito.

Sep 21, 2015

By Georg Petersen

El Perú es un país rico en diversidad de metales empleados en los campos de la minería, metalurgia, orfebrería y artesanía durante los tiempos pre-históricos. Dichos metales son: oro (objetos laminados por martilleo, repujados, pulidos, vaciados, soldados y dorados), plata (objetos trabajados de la misma manera que los de oro), cobre (objetos en diversas formas, como son discos, recipientes, herramientas y armas, en muchos casos dorados y/o plateados) y el azogue (cinabrio usado preferentemente para pintar las caras de los guerreros, las máscaras de los fardos funerarios y las caras de las mujeres nobles, costumbre que se generalizó a principios de la época colonial). De otro lado, existen otros cuatro metales que se emplearon en cantidades pequeñas como: fierro, platino, plomo, estaño.

Nov 1, 1970

By Jorge Fernández Maldonado

"La falta de una consideración adecuada sobre el papel eficiente que podría desempeñar una concepción coherente de la política energética en el desarrollo económico nacional, revela anomalías en el sector energético. En este sentido, el presente texto señala los principales problemas del sector energético y minero en el Perú. El objetivo amplio del Sector Energía se define como el abastecimiento oportuno, suficiente y económico de la demanda de los diversos sectores, dinamizándolos e incentivando positivamente el desarrollo, así como elevando los niveles de vida de toda la población y racionalizando la utilización de los recursos energéticos del país. Por ello, es necesario considerar medidas en los sub-sectores Electricidad e Hidrocarburos, así como el progresivo cambio de las condiciones económicas, donde se continuará estudiándolas y formulando proyectos de su empleo, de modo que sus posibilidades sean convenientemente analizadas y comparadas previamente a la selección de los proyectos energéticos que integren los programas nacionales. "

Mar 1, 1969

By Lytman Jordán

En la actualidad, el proceso de Ore Control de Tintaya se convierte en un reto porque la naturaleza del yacimiento Metasomático de Contacto Tipo Skarn presenta una mineralización compleja a manera de pasas en una torta. En ese sentido, la cultura Sigma -que presenta poderosas herramientas estadísticas y de gestión de procesos-, logró conceptualizar el proceso de ore control e identificar y optimizar tres sub-procesos críticos: el muestreo de Blasthole, preparación y análisis de Muestras de Blasthole y el Ore Control Operativo. Por ello, el presente texto señala la optimización del oro control de Tintaya a través de la metodología Six Sigma, donde se logra mejorar el proceso desde el muestreo de blasthole hasta el envío de mineral a las plantas, se minimiza los eventos de fuga de mineral a los botaderos y con la data confiable de los blasthole, se elaboran modelos de corto plazo que permiten generar planes predecibles de minado.

Sep 9, 2007

By Taylor R. G

This paper reports a biogeochemical study of the Siberia lode of the Herberton tin field. Soil near the orebody contained high levels of Fe, Cu, Pb, Sn, As, Mld Mn. Polycarpaea spirostylis and Indigofera dominii were associated with these high levels but several other species apparently could not tolerate them. The potential of these species as indicator plants is discussed.

Jan 1, 1975

By Juan Luis Bouso

El principal objetivo de este trabajo es conocer la distribución granulométrica de los productos grueso y fino que se obtendrían de un producto de alimentación en una separación o clasificación con hidrociclones. Asimismo, se busca determinar los principales parámetros que rigen la clasificación, como el tamaño de clasificación, generalmente conocido como d50, el reparto de masa en el clasificador y la carga circulante en caso de una clasificación en un circuito cerrado de molienda. Se recoge un procedimiento de cálculo que llamamos simulación, el mismo que se basa en el conocimiento matemático de la curva de la eficiencia de la separación en función del tamaño de corte deseado, o bien de alguno de los puntos de las distribuciones granulométricas de los productos a obtener en la clasificación.

Sep 20, 2019

By Nelson Rivera

El presente texto analiza la crisis económica y su relación con el Banco Minero. Para ello, se revisa las dos últimas recesiones económicas que tuvo el Banco entre 1975 y 1982, donde la crisis se agudizó por una caída en los precios de los metales y una inflación de costos que no pudo ser transmitida al precio de venta. Como consecuencia de ello, las empresas mineras que tuvieron préstamos, acusaron pérdidas en sus ejercicios e incumplieron en el pago de sus obligaciones. Como medida anti-crisis, el Banco Minero estableció comisiones de alto nivel para evaluar las situaciones y recomendar la dación de dispositivos legales que permitieron asistir a los Pequeños y Medianos mineros en la restitución de liquidez mediante préstamos sobre liquidaciones a precios deprimidos, Asimismo, generó la consolidación, refinanciación y moratoria de los clientes que estaban en suspensión de pagos de las obligaciones contraídas con el Banco Minero y la creación de líneas de crédito especiales para la Pequeña Minería.

Mar 1, 1985

The 1963 Lignite Symposium was held on the University of North Dakota campus, Grand Forks, N. Dak., April 30-May 1, 1963, under the cosponsorship of the University of North Dakota and the Bureau of Mines. This symposium, the third in a series, had as a general objective the dissemination of information concerning advances in technology and utilization of solid fuels, with emphasis on lignitic coals. Approximately 150 representatives of industry, government, and educational institutions from 21 states and 3 Canadian provinces were present at the symposium. Those attending were welcomed by Marling J. Ankeny, Director of the Bureau of Mines, representing the Bureau, and Dean T. H. Clifford, Vice President of the University, representing the University.

Jan 1, 1964

The 1963 Lignite Symposium was held on the University of North Dakota campus, Grand Forks, N. Dak., April 30-May 1, 1963, under the cosponsorship of the University of North Dakota and the Bureau of Mines. This symposium, the third in a series, had as a general objective the dissemination of information concerning advances in technology and utilization of solid fuels, with emphasis on lignitic coals. Approximately 150 representatives of industry, government, and educational institutions from 21 states and 3 Canadian provinces were present at the symposium. Those attending were welcomed by Marling J. Ankeny, Director of the Bureau of Mines, representing the Bureau, and Dean T. H. Clifford, Vice President of the University, representing the University.

Jan 1, 1964

By Michael J. Jorgensen, Pranathi B. Aedla, N. K. Kittusamy

Risk factors associated with the development of muscu­loskeletal discomfort and disorders during the operation of heavy mobile equipment include whole-body vibration and awkward and sustained joint postures of the shoulders, neck, and trunk. Cab design may influence awkward postures of the joints, and task duration may influence duration of exposure to awkward and static postures and whole-body vibration. To reduce exposure to risk factors related to the interface between cab design and task, it may be necessary for manufacturers to address cab design. This study assessed the repeatability of a cab design checklist developed to evaluate various design characteristics that can influence exposure to risk factors for musculoskeletal discomfort. The ability of the cab design checklist to identify posture-related deficiencies of design was also assessed. The checklist was used by two administrators across 10 pieces of heavy construction equipment. Video analysis was performed to quantify postures of the neck, shoulder, and trunk; correlation analysis was used to determine whether specific questions from the checklist were associated with the identification of awkward postures. The repeatability assessment resulted in kappa coefficients ranging from 0.52 to 1.0 (good-to-excellent reproducibility) across each piece of equipment, and an overall kappa coefficient of 0.77 (excellent reproducibility) when considering all equipment together. Results from the correlation analysis showed that shoulder flexion posture was correlated with scores from the cab design checklist. However, results of the cab design checklist were not significantly correlated with shoulder abduction or awkward postures of the neck and trunk. Results suggest that the cab design checklist may be useful for identifying cab design characteristics that need further improvement and for identifying design characteristics that increase shoulder flexion. The strength of the repeatability assessment suggests that outcomes of the cab design checklist administered by different individuals may be consistent, independent of the type of equipment being assessed.

By Henry P. Wheeler

As recently as 1915, helium was available only in very small quantities at a cost equivalent to $2,500 per cubic foot. It was a laboratory curiocity, and its properties were of interest to a limited number of scientists (11).3/ During the past 30 years, however, helium has grown from a plaything of scientists to a factor of importance in the prosecution of the recent war. Navy blimps filled with nonflammable helium proved to be more than a match for German submarines operating in the Atlantic. American bombers were able to fly unheard-of distances to drop bombs on Tokyo, Nagoya, Yokahama, and other Japanese cities because they had been made lighter with magnesium, arc-welded in a helium atmosphere. The Army utilized helium-filled radio-sonde balloons to obtain vital information concerning weather conditions affecting D-day invasions and other military maneuvers.

Jan 1, 1946

By B. H. Grimes

El presente texto describe el equipo, las técnicas de fotografía aérea y los nuevos procedimientos para interpretar los resultados de la exploración de recursos minerales en el país. Dicha técnica comprende dos tipos principales de fotografía: vertical y oblicua. La fotografía vertical es un mapa pictórico y da una visión en planta del terreno, mientras que la oblicua, se aplica cuando se desea una interpretación fotográfica detallada en gran escala -particularmente al estudio de bosques cuando la cubierta de los árboles enmascara los detalles de la fotografía vertical. De otro se refieren las técnicas y los equipos fotográficos, la estereofotografía y la detección remota, la cual permite obtener más información que con la fotografía usual, puesto que aprovecha sólo la parte visible del espectro.

Mar 1, 1974