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By Richard Quirk

This report describes methods and techniques employed by The Glidden Co. of Cleveland, Ohio, in explorating an ilmenite-bearing sand deposit in Ocean County, New Jersey, during 1960 to determine ore reserve potential and the feasibility of mining and establishing a milling plant on the property for the production of ilmenite concentrate. The property covered approximately 1,250 acres. Comprehensive sampling by water-jet drilling indicated the deposit averaged 20 feet in thickness and contained 4.5 percent heavy minerals, of which 80 to 85 percent was ilmenite and leucoxene. Average depth of the water table as determined by auger boring was 16.8 feet. Pilot plant tests indicated that circular concentrators in combination with spiral concentrators would recover at least 80 percent of the heavy mineral content of the sands. It was estimated that sufficient ore reserve tonnage had been developed to supply the company's Baltimore chemicals division, pigments department, with a suitable grade ilmenite concentrate for a period of 20 years at the present rate of pigments production. The property was designated as Lakehurst mine and plans are in progress for mining development and plant construction.

Jan 1, 1963

By Amado Yataco

El presente texto describe el aporte de las regiones respecto al PBI minero durante el período Enero- Noviembre 2016. Para ello, se contrasta los niveles de producción de los diferentes metales producidos con la potencialidad de los recursos mineros de cada región. El PBI Minero permite expresar en una sola cifra el valor bruto del conjunto de minerales metálicos producidos a nivel nacional, regional o local. Las regiones evaluadas son: Arequipa, Junín, Cuzco, Ancash, Apurímac, Pasco, Tacna, Ica, La Libertad y Cajamarca.

Jan 1, 2017

By Bernard Lewis

During the past 10 years the technical investigations conducted by the Explosives Division of the Mine and Explosives Bureau of the Bureau of Mines have been described in a series of summarizing reports prepared by Wilbur I. Huff, consulting explosives chemist of the Bureau. These reports covered the…

Dec 1, 1947

By Eleanor Sonley

In October 2000, temporary seismographic stations were installed above the Trail Mountain Mine, Emery County, Utah, USA to supplement a regional network. Over seven months, 1826 mining-induced seismic events were recorded with a magnitude range of M 0 to M 2.2 (Arabasz et al., 2002, 2005). Routine event locations for this dataset cluster around the longwall mining activity during the recording interval. However, applying a double difference relocation technique to the routine locations significantly improves the correlation between mining activity and event location. The resulting relocations depend greatly on station distribution and the number of arrival time picks. We use this dense temporary array to assess station distribution requirements for applying the double difference technique at other mines by systematically removing data from available stations, thus simulating sparser networks. The insight gained using the Trail Mountain dataset is used to develop a metric for assessing the usefulness of above-mine networks and to develop a tool for expanding seismic network coverage. To verify the appropriateness of these tools for wider application, we examine data from two additional mines located in the western United States. Improving the relative locations of mining-induced seismic events highlights the association of these events with active portions of the mine. Clusters, regions of quiescence and relative timing of events can be used by mine operators to assess hazard, optimize production, and evaluate performance of mine plans. The lessons learned from this study may be used in future network design to improve accuracy of event locations at other mines.

Jan 1, 2009

By F. G. Heivilin

We are no longer short of viable Rare Earth deposits. As little as 2 years ago China mined and produced 97% ofthe world?s rare earths. Only a few deposits were in an advanced stage of exploration and development. Now Technical Metals Research (TMR) Gareth Hatch *5 reports that 347 deposits are being developed by 265 companies down from 440 on July 6th. Their Index of Advanced projects lists 45 projects in 14 countries. They will sustain the world for centuries to come and many good deposits are yet to be found. The problem is mining 14 elements in balance. Each of the deposits listing production in the chart has a unique set of minerals which they think will give them a cost advantage. Which of these will make it to production is a question. Most of the Advanced won?t be mined soon, but which ones? China is still in the driver?s seat in Light Rare Earth production (LREO) with one deposit with 35 million ton Baiyunebo deposit in Inner Mongolia which is part of a working iron ore deposit. The number of HREE deposits have been reduced and they attempting to eliminate unpermitted mines. This report will tell you what a Rare Earth is, how rare they are, why they are important, and where they are being developed which includes Australia, the United States, Africa, Greenland, Brazil and Canada.

Feb 27, 2013

By Pedro S. Zúñiga S.

El presente trabajo señala la optimización de los parámetros de perforación en el yacimiento minero de Cuajone a través del control de presión hidráulica y velocidad rotacional en la operación de máquinas de acuerdo a las formaciones geológicas consideradas. En este sentido, se busca mejorar el rendimiento respecto al desgaste de brocas y conservación de la máquina perforadora.

Oct 14, 1980

By Oscar Rojas

"San Ignacio de Morococha S.A es una empresa que está innovando sus operaciones, por lo que cuando se dio la necesidad de mejorar el diseño de la malla de perforación para labores mineras subterráneas de un cuadrante de 4 m x 4 m; se inició un trabajo de investigación para poder aplicar el Modelo Matemático de Holmberg, para luego ser implementado en otras labores mineras del mismo cuadrante. Al realizar pruebas, se obtuvo resultados satisfactorios mostrando avances ya no de 2.75m, sino avances superiores a 3m. Paulatinamente se realizaron ajustes de la disposición de los taladros, burden y espaciamiento hasta unificar el nuevo diseño."

Sep 1, 2017

By Jack Eloranta

The winning of metals often requires fine grinding of very hard ore. The US Bureau of mines measured compressive strengths exceeding 100,000 PSI (700 MPa) in Minnesota taconites. Grinding down to 300 mesh (50 µ) is required for some fine-grained taconites. While other metal ores may not be as strong, significant grinding costs are the rule rather than the exception. One author recently reported that a 7% drop in grinding costs would fully offset a doubling of the drill and blast budget. Another author found that drill and blast costs were 13% of the costs of producing iron ore concentrate while fine crushing and grinding were over 60% of the cost of producing concentrate.

Jan 1, 2013

By D. Rahal, I. Shah, B. Hines, S. Reddick

"The development of stirred milling technology has proven to be an enabling technology in fine grained metallic deposits. The increased grinding efficiency allows for the economic size reduction required to produce saleable concentrates. This improvement has opened the door to retreatment projects such as reprocessing of historic gold mine tailings. Recently a VXP2500 stirred mill was installed at Casmyn Mining Zimbabwe Turk mine to allow the reprocessing of historic mine tailings. After commissioning, an extensive joint research project between Casmyn and FLSmidth Minerals was conducted to optimize the performance of the mill. This paper outlines the challenges encountered in the optimization program and the outcomes from the joint research project.INTRODUCTION The development of stirred mills has opened up many new opportunities to recover valuable minerals from refractory ores. Stirred mills have already been reported as an enabling technology for the processing of fine grained ores in lead/zinc applications (Pease, Young and Curry, 2005). Historically, conventional ball mills were unable to economically grind material fine enough to produce the required recovery or concentrate grade. This often resulted in the loss of valuable materials to the final plant tailings. The advent of stirred milling has now provided an opportunity which has both economic and environmental benefits, the reprocessing of historic mine tailings. Many tailings stockpiles now contain economic concentrations of gold because of the ability of stirred mills to efficiently and economically grind the tailings to liberation sizes. The primary advantage of reprocessing historic tailings is very low cost processing. Recovering the tailings is usually as simple as pumping the material into the reprocessing circuit. The disadvantage of reprocessing tailings is the low feed grade and greater difficulty in recovery valuable minerals at the same size distribution. The material has already been previously processed so fresh surface area or an increase in metal exposure is required. These are both provided by regrinding the tailings material."

Jan 1, 2014

By Ricardo Arrarte

El presente texto describe la optimización del método de corte y relleno ascendente en la minería subterránea peruana a través de un modelo matemático matemático que minimiza los volúmenes de roca usando la programación lineal, y tiene como resultado las distancias de ubicación de las rampas, pendientes de las mismas, número de cortes a realizar en el tajeo, radios de curvatura, y otros parámetros adicionales.

Sep 14, 2009

By A. G. Sciulli, G. P. Ballock, K. K. Wu

Waste disposal underground is the most effective method when viewed from an environmental aspect. As costs of other methods of disposal continue to escalate, the cost effectiveness of underground disposal during the mining cycle becomes increasingly attractive. The use of concrete for sealing abandoned mines has proved to be suspect when associated with a relatively incompetent adjacent strata due to its shrinkage characteristics. Complete failure of the plug has been known to occur in some instances. A more effective, cost competitive seal can be obtained using pneumatically stowed material and incorporating a polyurethane grout, which has greater adhesion characteristics than concrete. Injection of the surrounding strata and of the stowed material helps to ensure an impervious barrier and prevent the plug from moving when subject to high pressure heads. When properly placed, impervious seals cause the old workings to flood, raise the mine pool level, and thus eventually eliminate the potential for oxidation, which is the primary cause of acidity in the water.

Jan 11, 1986

By Irving Wender

This report describes Bureau of Mines experiments and reviews the work of others on the exposure of coal and coal-derived products to gamma rays and some other types of radiation. Results are presented on tests of three bituminous coals and a lignite that had been pulverized to minus 200-mesh particles and exposed to 1,000 megaroentgens of gamma irradiation from spent-fuel elements of a nuclear reactor. Of about 20 chemical and physical tests in Bureau work, only mass spectrometry of gases evolved during vacuum pyrolysis of the coals to 450° C gave results indicating differences in the irradiated and unirradiated samples. Mass-spectral distribution curves for CO and CO2 evolution showed fewer irregularities (reversals of curvature) for irradiated coals; thus, mass spectrometry appears to be the most sensitive method for determining radio-induced changes in coal. It is concluded that coal is not significantly altered by gamma irradiation owing to the resistivity of its highly condensed ring structure. High-level gamma irradiation, therefore, is unlikely to prove advantageous in coal processing and utilization. Specially treated coals, because of resistivity of coal to radiation damage, may be useful as an absorbent in processing radioactive wastes.

Jan 1, 1968

By H. W. Wainwright

.1. The purification pilot plant and the equipment, solution, and gas cycle used for removing hydrogen sulfide and carbon dioxide are described. 2. As sulfur recovery is necessary in any large Fischer-Tropsch plant, pilot-plant runs were made at 300 p.s.i.g. to study the efficiency of tri-ethanolamine solutions in removing selectively hydrogen sulfide from gases containing varying amounts of carbon dioxide. 3. Aqueous solutions of TEA of 20, 30; 35, and 50 percent were investi¬gated. Data indicate that 30 to 35 percent is the optimum concentration if both selectivity and economy are considered. Slightly better selectivity is obtained with the.20 percent solution, but steam consumption is greater owing to the higher solution rates. Results from our pilot plant runs indicate that a 50 percent solution not only produces an acid gas of lower hydrogen sulfide content but also requires high solution rates to effect hydrogen sulfide purification. 4. Data from 37 runs using TEA are presented in tabular form. In addition, the data are correlated and presented in three sets of curves. By using these curves, it is possible to calculate the compositions of the purified and acid gases for various raw gas mixtures. 5. In cooperation with the Southern Natural Gas Co., investigations were carried out at 300 p.s.i.g. on the simultaneous removal of hydrogen sulfide and carbon dioxide, from gases using various concentrations of diethanolamine. 6. Data from 17 runs employing 20, 30, and 40 percent DEA are reported in both tabular and graphic form. 7. A comparison of the data from one DEA run made at 200 p.s.i.g. with those from the runs operating at 30O p.s.i.g. shows float the absorption capacity of the solution, and, hence, the steam requirements per gallon are about the sage for both pressures. .The only real advantage of the higher pressure is the additional volume of gas that can be treated. 8. The quantity of steam needed to reactivate fouled TEA and DEA solutions increased as the reactivator pressure was increased about 1,0 to 1.1 pounds of steam was required for each gallon of circulating solution when the reactivator was operated at 5 p.s.i.g. 9. A curve is included that shows the effect of the hydrogen sulfide con-centration in a lean 35 percent TEA solution on the hydrogen sulfide content of the purified gas and on steam consumption for reactivation. 10. Both TEA and DEA reduced the organic sulfur content of the raw synthesis gas considerably. Analyses of the lean amine solutions showed a gradual build up of sulfur compounds, indicating that the compounds formed by the amines and organic sulfur do not break down under the ordinary operating conditions of the reactivator. 11. Considerable operating difficulty was encountered in the pilot plant owing to foaming of the amine solutions. Laboratory experiments in which the effectiveness of certain antifoam agents was studied showed Alkaterge C to be most promising for the particular conditions studied.

Jan 1, 1952

By Manuel E. González

El presente trabajo refiere las relaciones entre empresa y servidores a cargo del departamento de Relaciones industriales en la Cerro de Pasco Corporation. El desarrollo de las relaciones laborales dentro del yacimiento minero se basa en el medio o contexto, supervisores, fuerza laboral, oficina de empleos, comunicaciones, servicio social, campamentos, etc. Además de considerar estos aspectos, es necesario mencionar que la armonía laboral requiere del cumplimiento de los dispositivos legales del país, la predisposición de los supervisores y personal a cumplir con las condiciones de trabajo, la garantía del derecho del trabajador a expresar sus incomodidades a la empresa y el procedimiento respectivo de la gestión apelada, cuyo plazo será respondido dentro de 2 días.

Jul 20, 1960

By Erwin Olivera

Este sistema integral de seguridad instalado en la pala eléctrica N°5 está conformado por un conjunto de cámaras, sensores de proximidad de objetos y de luces led rojas ubicadas en la parte lateral y posterior del equipo permitiendo al operador de la pala, tener una mayor visión y control de su área de trabajo y al operador del equipo auxiliar, le permite restringir la entrada del equipo al radio de giro de la pala. Por tal motivo la Gerencia Mina de Cuajone decidió instalar este sistema integral a todas las palas de la operación para el año 2017 lo que permitirá generar un ahorro a partir del año 2019 en pérdidas de la producción, gastos por parada del equipo auxiliar y gastos por reparación por un monto de US$ 40,619 anuales.

Sep 1, 2017

By H. Mogollón

El presente texto señala el proceso de fabricación del alambre y cobre en la Cerro de Pasco Corporation, así como los métodos adecuados para su elaboración. Bajo el amparo de la ley 13270 de promoción industrial nace la Compañía Industrial del Centro, subsidiaria de dicha corporación, y responsable no solo de la producción de barras y alambrón de cobre, sino de la producción de ácido sulfúrico en La Oroya. Actualmente, esta producción se ajusta a 90 toneladas métricas de alambrón redondo de cobre refinado con un diimetro nominal de 7,9375 mil metros. Sin embargo, esta pueda ampliarse hasta un máxlmo de 145 toneladas métricas a través de cambios menores en el equipo auxiliar.

Nov 20, 1967

By R. J. Mechin

TOP-SLICING was introduced in the Pachuca district in 1917 by T. C. Baker, at that time mine superintendent, of the Santa Gertrudis mine. There then existed 1200 ft. (365.7 m.) below the surface, lying between the fourteenth and eighteenth levels (a vertical distance of 108 meters) a block of ore having a length of 295 ft. (90 m.), and an average width of 82 ft. (25 m.) and dipping at an angle of 65°. This block lay in the hanging wall of the vein and consisted of highly altered and fractured andesite, cut through with mineralized quartz stringers. On the foot-wall side, 26 ft. (8 m.) of old filling, left by former operators, was of payable grade. Stoping therein was first undertaken by the square-set filling system, but because of the extremely heavy hanging wall and loose dry filling in the foot wall, all square setting had to be accompanied by spiling, which made the operation exceedingly slow and costly. A system of mining was sought that would eliminate the difficulties inherent to the square-set system in heavy ground and that at the same time would effect the desired economies in mining. After several years, top-slicing has met all the conditions most satisfactorily, so that when similar conditions presented themselves in El Bordo mine, this method was adopted with necessary modifications. El Bordo mine is operated by the Santa Gertrudis company, and is situated about two miles north of Pachuca. Because of the diversity of the orebodies, a number of different mining methods are in use, among them top-slicing.

Jan 10, 1925

By Jan Boon

Las compañías de exploración junior realizan actividades de exploración que pueden establecer eventualmente una mina. En ese sentido, el presente texto señala la aplicación del modelo dominante RSC (Asociación de exploradores y desarrolladores de Canadá) en la calidad de las relaciones de la comunidad minera y los empresarios. Es decir, se muestra el poder explicativo de la herramienta de caracterización de relaciones empleada en un marco interaccionista y que puede ser aplicada de manera inclusiva en el campo de la RSC.

Sep 1, 2013

By Gustavo De la Torre Guzmán

En planta concentradora – Cerro lindo en su afán de consolidarse como una operación de categoría internacional, mantiene el enfoque de excelencia operacional gestionando de forma sistemática seguridad, salud ocupacional, medio ambiente, costos, productividad, calidad y confiabilidad además de nuestro proceso productivo. Para lograr el desempeño de categoría mundial y ser catalogados como tal, implica también usar la capacidad total del área (procesos, tecnología y talento humano) para implementar estrategias de optimización que garanticen la efectividad de las operaciones, para el éxito del proceso.

Sep 1, 2017

By D. Govender

In recent years, economies of scale have continued to drive copper projects to larger throughputs to offset depleting lower grade resources. A decade ago there were only a small number of projects that stretched beyond 100,000 Mtpd throughput rates. Nowadays and moving forward virtually all the major copper projects are sized beyond this, with throughput rates up to 250,000 Mtpd now under evaluation for a number of key projects in Chile and Peru. This paper explores the development from the 160 m3 flotation cells, through to the 257 m3 cells and nowadays to the 660 m3 machines. The contributions of specific copper concentrators to this growth phase are reviewed herein. The historical basis of flotation machine scale-up is also briefly discussed. Metallurgical results as well as layout, maintenance and operational aspects are highlighted.

Feb 27, 2013