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Research into the mechanisation of ore winning from the very narrow reefs characteristic of South African gold mines has been conducted from as early as 1964 through the Chamber of Mines Research Organisation (COMRO) but with limited success. However, the Council for Scientific and Industrial Research (CSIR) has recently re-evaluated the potential for the mechanisation for the narrow tabular gold mines. It has been determined that there are approximately 22 000 tonnes of gold left in-situ in channel widths of less than 500 mm in thickness. The extraction of ore from such reefs requires a complete paradigm shift in that the current mining cycle (drilling, blasting, cleaning and supporting) is not feasible since such a stoping width would not allow the workers entry into the stope. Consequently, a non-entry form of mining is required. With this target in mind CSIR has invested in a project called the Nederburg Miner which seeks to identify new technologies for drilling, rock breaking, cleaning, and materials handling, the application of which will enable non-entry mining of very narrow ore bodies. The intention is to develop a fully automated system that will not require human involvement at the stope face. The outcomes of research into this proposed system will not only extend the life of South African gold mines but will also enhance South Africa's reputation for excellence in mining research. This paper presents the new technologies under consideration and potential methods for their application into an integrated non-entry mining system.

Jan 1, 2008

By H. P. LeVan

The aced for reliable reserves of the essential element, manganese, has been a continuing concern of the Federal Government for more than three decades. Because of the increasing vulnerability of outside sources of supply efforts have been intensified to find a means for beneficiating United States domestic deposits. The deposits of most interest would of necessity be near, or have access to, suitable transportation to processing plants. The Georgia manganiferous iron deposits represent some 10 million tons4 of ore readily available to southern iron and steel industries, if a manganese recovery process capable of functioning in the presence of large quantities of iron can be developed. In addition, a successful method for beneficiating the Georgia ore could produce a significant quantity of high-grade iron concentrate. The Differential sulfatization process developed 47 the Bureau of Mines5 seemed to be well suited for this application, particularly because it results in low concentrations of iron in the leach liquors with relatively complete extractions of manganese. In this process, manganese in the presence of iron is preferentially reacted with sulfur dioxide at elevated temperatures and subsequently extracted with water.

Jan 1, 1962

By Pitter Huapaya, Enrique Segura, César Espejo

La reactivación química o lavado químico se realiza con la finalidad de retirar el carbonato, sulfatos y demás iones que incrementa la alcalinidad, los cuales también son adsorbidos por el carbón. Es en esta etapa que se vio una oportunidad de mejora debido a que luego del lavado químico debido al uso de ácido clorhídrico hay presencia de complejos de cloro que quedan adsorbidos en el carbón activado y al retornar al proceso de adsorción restan la eficiencia para el reusó en el proceso haciendo que el tiempo de saturación se reduzca, perjudicando a la ley del barren por saturación temprana del carbón y para contrarrestar se tiene que incrementar el número de desorción.

Sep 29, 2023

By J. Don Scott

Analytical predictions of the rate and magnitude of settlement of deposited oil sands tailings slurries generally overestimate how fast pore pressures will dissipate. Field deposits of nonsegregating tailings to mature fine tailings show continued high pore pressures near the surface which impede surface reclamation. In geotechnical analyses which predict the consolidation behavior of soft soils a finite strain theory is used. Effective stress-void ratio and void ratio-hydraulic conductivity relationships determined from laboratory large strain consolidation tests, are used in the finite strain predictions. This theory, however, cannot predict the full range of sedimentation, consolidation and pore pressure dissipation which occurs in large scale deposits of thixotropic tailings slurries. A new large strain consolidation model which assumes that the creep rate of the slurry exceeds the pore pressure dissipation rate is being investigated. This model is relevant for rapidly deposited, low permeability thixotropic slurries where the upwards drainage path increases by several meters a year, such as, in oil sand fine tailings ponds and nonsegregating tailings deposits. The model will be verified by analyzing the 10m high column of fine tailings at the University of Alberta which has been monitored for over 20 years and in which the excess pore pressures are still very high.

May 1, 2004

By Benjamin A. Allou

La seule production de columbo-tantalite réalisée en Côte d?Ivoire est effectuée dans les éluvions et alluvions du gisement d?Issia, localisé au Centre- Ouest de la Côte d?Ivoire. Même si un lien direct avec les roches granitiques est suspecté, aucune attention particulière n?a été accordée à l?étude de la minéralisation primaire en relation avec l?évolution des granites et des pegmatites associées. Ces granites, qui sont en intrusion dans les roches sédimentaires du Protérozoïque inférieur, comprennent : le granite orienté à deux micas (Lobo), le granite orienté à muscovite dominante (Bitapia) et le granite porphyroïde non orienté à muscovite dominante (Issia). Les résultats de cette étude indiquent que les pegmatites à Nb-Ta-Be-Li sont liées au granite de type Issia. Les observations de terrain et les analyses sur roche totale des granites montrent que: (1) les trois principaux granites de la région sont de type- S et peralumineux dans leur composition, (2) ils ont été formés pendant la période tardi- à post-Éburnéenne, (3) le granite d?Issia fut le dernier à se mettre en place. Les pegmatites liées au granite d?Issia ont été classées en quatre types : Apegmatites stériles; B- pegmatites à Be; C- pegmatites zonées à Nb-Ta-Be; et Dpegmatites zonées à Be-Nb-Ta-Li. Les pegmatites zonées comprennent les zones suivantes: I- zone à aplite; II- zone graphique; III- zone à albite, microcline, béryl et columbo-tantalite; IV - zone à microcline massive; V- zone à quartz. Ces pegmatites présentent une zone d?altération métasomatique externe. La minéralisation de Ta, Nb et Be est liées à la zone III des pegmatites de types C et D, et celle de Li est associée aux greisens qui peuvent être observés n?importe où dans les pegmatites de type D. Les données de terrain et de laboratoire indiquent que le granite d?Issia est la roche parentale des pegmatites à éléments rares de la région. Les pegmatites minéralisées sont distribuées seulement autour du granite d?Issia et les patrons des terres rares des granites et ceux des pegmatites à éléments rares sont très similaires. Les analyses de la composition totale montrent un lien génétique entre le granite d?Issia et les pegmatites à éléments rares. Il est suggéré que les pegmatites ont été formées durant le transport et la cristallisation fractionnée du magma.

May 1, 2003

By Miguel Galindo, Eleuterio Rivera

Las características mineralógicas cada vez más compleja e inciertas de las distintas fases de minado, representan en general nuevos desafíos operacionales en las distintas etapas de los procesos minero-metalúrgicos: chancado, molienda, flotación, bombeo por mineroducto, filtrado y almacenamiento. Los cuales se enfocan principalmente en cumplir y optimizar la calidad final de los concentrados producidos sin incrementar significativamente los costos operativos y maximizando el uso de los recursos existentes.

Sep 29, 2023

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

By Barry A. Hillman

The rapid evolution of computer and field sensor technology is now providing the ability to integrate mine and office operations. Digital maps and mine plans as well as CAD and GIS can be transferred to ruggedized field computers for development of real-time mine surveys and real-time GPS machine navigation and monitoring. Surveyors can insure that their surveys are accurate before returning to the office. Engineers and surveyors are also able to upload field computer-based surveys to mine planning software and directly to mine equipment including shovels, drills, and dozers providing the operator of the equipment with a real-time view of their work space. Production information can be transmitted through dispatch and/or centralized mine servers to update mine plans with mining progress and production data. Static mine models then become a dynamic element of operations, providing greater use of information that emphasizes the spatial aspects of the mine by providing real-time maps, productivity charts, and graphs. This information can be disseminated through various mine communication systems to provide operators and management with real-time feedback as well as daily and weekly reports. Integrated systems now being used in extensive trials are reporting productivity increases of 4 -7% or more thereby providing rapid payback to the mine.

Jan 1, 1998

By Nicholas Enraght – Moony, Alvin Johns, Zhonghan Zhang, Zhang Xianhua, T. Choo

"The tungsten (WO3)-rich ores from King Island Scheelite (KIS) Mine, Australia, containing scheelite(CaWO4) were previously recovered by gravity separation and flotation of fine scheelite (1978-92) with an overall recovery of 76% when both circuits were operating. Recently extensive test work has been conducted both in China and in Australia on KIS ores, assaying from 0.50%-1.34%WO3, and tailings assaying 0.2%WO3(GZRINM 2009; 2011a; 2011b). A new approach, which aimed at improving both recovery and grade of concentrate by means of an innovative all flotation route WOF (Whole Ore Flotation), achieved excellent results: 90%-92% recovery to concentrate grade of 66%-70%WO3for the ores. The process is characterized by the use of selective reagents in flotation, including a newly developed collector for scheelite, GYWA. The WOF process also embraces the "Improved Petrov Method" in the cleaning of scheelite rougher concentrate. Earlier investigations found that the removal of sulfides by flotation prior to scheelite flotation was not necessary. It was also found that recycling of process water did not influenceresults. Two main ore types were tested as well as tailings from 2009to 2001(0.20%WO3). In addition a flow sheet using wet high gradient magnetic separation (WHGMS) in tandem with flotation was also investigated for the tailings."

Jan 1, 2014

By E. S. Shedd

Amenability studies were conducted by the Federal Bureau of Mines on an electrooxidation technique for the extraction of mercury from cinnabar ores, particularly those that are too low in grade to be furnaced or retorted economically. Oxidation was accomplished by electrolysis of the ore while slurried with brine. Mercury was dissolved through the formation of the soluble tetrachloro mercury complex, HgC142-. Mercury extractions ranged from 90 to 98 percent in 4 to 6 hours of processing time when tests were made on eight different types of cinnabar ores containing from 0.7 to 18 pounds mercury per ton ore. Salt concentration was varied from 4 to 10 weight-percent depending on whether Pb02 anodes and iron cathodes were used or whether graphite was used for both electrodes. Power consumption ranged from 17 to 64 kilowatt-hours per ton of ore treated. Ninety-nine percent of the mercury was recovered from pregnant solutions by precipitation on an active metal such as zinc, followed by distillation of the resulting amalgam at 600° C.

Jan 1, 1975

By C. L. Dake

AN insistent and steadily growing demand is evident for the broadening of undergraduate curricula in engineering. Among suggested additions are training in public speaking, report writing, business law and contracts, accounting, finance, money and banking, scientific management, economics, social and labor problems, psychology, and ethics. The demand for these subjects comes from the older engineers and from the industries that employ our graduates. Of course, many of the men who suggest such changes are influenced largely by their personal needs and contacts, but the demand is sufficiently widespread to merit serious study by educators. In fact, many educators themselves concur in the proposals for broader training. These matters were examined intensively a few years ago in an exhaustive study of engineering education. Opinion at that time was rather strongly against any profound change. Since then, however, the whole economic system has undergone violent disruption. Even if recommendations made a few years ago were appropriate to the conditions then- obtaining, the enormously changed conditions of the present make advisable a further careful study of this problem. In recent years, mergers, to reduce costs, have sharply limited the number of engineers employed and have thereby intensified the struggle to secure positions. In this stiffer competition, engineers with the most adequate training undoubtedly fare the best.

Jan 1, 1934

Two of the problems long associated with the complete extraction of level pillars in the wide ore bodies of Broken Hill have been: (1) The high cost of maintaining level gangways through areas of slow subsidence to provide adequate trucking roads for the transport of sand filling; and (2) The difficulty and high cost of completely filling depleted areas. This paper deals with the experiments conducted to devise an apparatus for transporting, with the aid of compressed air, sandfill from the underground sand passes to the stopes and describes the sand blower which has been developed. This apparatus has to a large degree overcome the difficulties and removed much of the hazard associated with the rapid extraction of level pillars.Special attention is drawn to the sizing analysis of the sand and to the fact that it is not dry material. It was early found that these factors were determinants in the design and development of the apparatus described.Acknowledgment is made to the General Manager of Broken Hill South Limited for permission to present this paper, to the engineering department for assisting in the design of the apparatus, and to the underground staff for their co-operation in training the operators and in bringing to success this method of stope filling.PREVIOUS FILLING METHODSThe South Mine, with a monthly production of approximately 32,000 tons of lead-sHver-zinc sulphide ore by cut-and-fill mining methods, requires about 11,000 cubic yards of filling per month. With the exception of a small and variable quantity of developmental mullock, all this filling is...

Jan 1, 1941

By Giselle Vera

En este estudio se identificaron y evaluaron alternativas de cierre para una Planta Concentradora de un proyecto minero ubicado en Perú, considerando medidas de cierre convencionales como; desmontaje, desmantelamiento y demolición, además de opciones de transferencia, entre otras. Se tuvo en cuenta la caracterización de las condiciones ambientales y socioeconómicas de la zona, actividades de terceros, aspectos legales relacionados a la alternativa evaluada y aspectos técnicos y económicos de las medidas de cierre identificadas.

Sep 29, 2023

By J. M. Candia

El presente artículo describe las rampas o túneles inclinados utilizados en el nuevo sistema de minería que permiten la circulación de vehículos y equipos pesados que se mueve sobre llantas de jebe con el objetivo de reducir los costos de explotación, manipuleo y extracción del mineral de baja ley que en otro sistema no podría trabajarse económicamente.

Jan 1, 1971

By D. P. Richards

Tunneling in carbonate sedimentary rocks such as lime stones and dolomites can be difficult when solution channels or voids are anticipated. Addressing the risk aspects associated with these formations can be done effectively through the Geotechnical Baseline Report (GBR) by properly characterizing the ground and ensuring that the Owner?s and the Contractor?s interests are represented and protected. This paper presents a review of tunneling difficulties in these rocks and includes a review of site investigations, geologic characterization, and presentation in the GBR. Key construction issues are also discussed, including appropriate excavation technology, mechanisms of face support and groundwater control, and quantifying grout takes.

By Alexandra Nieves, Artemio Pérez

Antapaccay, empresa minera ubicada en la provincia de Espinar; realizó un diagnóstico a profundidad sobre las causas de la conflictividad social. Ello conllevó inicialmente a la creación de herramientas para controlar el riesgo que posteriormente fueron analizadas a profundidad para entender la dinámica del territorio y establecer una estrategia de intervención social con enfoque estratégico. Es así como nace el “Sistema de Gestión de riesgos sociales y transformación de conflictos de Antapaccay, metodología que nos está permitiendo reducir los microconconflictos , conflictos socioambientales y socio políticos.

Sep 29, 2023

By Jorge Olivari Ortega

"La plata fue un metal de apreciado valor para las sociedades pre-hispánicas -en tanto los mineros lo obtenían de forma pura y se beneficiaban como metales argentíferos. En ese sentido, el presente texto describe su historia y usos en las sociedades pre-hispánicas. La plata se encontraba en los filones hidrotermales, asociada a la argentita, un sulfuro de plata, y calcita, así como a diversos sulfuros y arseniuros de níquel-cobalto-bismuto. Asimismo, gracias a sus propiedades físicas como color, brillo y maleabilidad, se puede trabajar fácilmente y obtener bellos objetos zoomorfos (auquénidos andinos: llamas, alpacas y vicuñas) para los rituales de fertilidad del ganado."

Nov 1, 2016

Uno de los principales objetivos de los trabajos analíticos del laboratorio químico, es la determinación del sílice libre como sustancia causal de la silicosis en los yacimientos mineros. Sin embargo y durante mucho tiempo, se creía que los minerales compuestos de silicatos (silicio y oxígeno) contenían grandes cantidades de sílice libre, olvidando que dicho elemento está compuesto solo de cuarzo puro. En este aspecto, el objetivo del presente trabajo radica en la búsqueda de reactivos químicos que disuelvan solamente los silicatos, sin alterar la sílice libre. Para ello, es preciso evaluar el porcentaje de dicho compuesto a través de dos métodos: químicos y los físicos. Los primeros se subdividen en el método de Goldmabn, de Knofp, Durkan Landry y Talvitie, mientras que en los segundos, tenemos al método petrográfico, método de difracción de rayos, de fusión, de diferencia térmica y sedimentación. De acuerdo a la aplicación de los métodos primeros, se comprobó que solo el método químico Talvitie es el más idoneo para la determinación del compuesto, dado que ahorra tiempo al disolver los silicatos en polvos industriales en un período de 20 a 30 minutos, así como por el uso de un equipo de laboratorio menos sofisticado, obteniendo como resultado el 39.7% en su composición y una desviación standard de 0.39. Aunque para algunos tipos de minerales se recurre al microsocopio petrográfico.

Jul 20, 1957

By Pedro Hugo Tumialán de la Cruz

Dado que el Perú ocupa el segundo lugar en la producción de plata a nivel mundial, el presente estudio describe la metalogenia de este metal. Respecto de su fisiografía y geología, se tienen rezagos de la Cordillera con rocas metamórficas del Pre-cámbrico, rocas metamórficas y sedimentarias del Paleozoico y Mesozoico en el suroeste del Perú y noroste del Perú en Paita, Illescas y Amotape. Mineralización de platacomo un subproducto se encuentra en los siguientes yacimientos: exhalación volcánica marina, yacimientos relacionados a diques de inyección magmática félsica, yacimientos tipo pórfidos de cobre, yacimientos tipo skarn, yacimientos de reemplazamiento y relleno en calizas, yacimientos de oro y plata en areniscas-cuarcitas-pizarras, yacimientos tipo cordillerano, yacimientos de oro y plata de baja ley de alta sulfuración y yacimientos tipo Mississippi Valley.

Aug 1, 2012

By Augusto Cabrera La Rosa

La explotación del carbón en el Perú no ha alcanzado un desarrollo sostenible debido a factores económicos, a pesar de las importantes reservas que tiene. En ese sentido, el presente texto señala la situación del carbón peruano, así como las mejoras para impulsar su producción a nivel nacional. Para ello, es necesario una mayor facilidad en el empleo de la electricidad y de los combustibles líquidos y gaseosos derivados del petróleo como en las cocinas domésticas, así como la estimulación en la sustitución del petróleo por el carbón en diversos usos. Asimismo, el Estado desarrolla un plan donde se beneficie a los mineros particulares de producción de carbón a través de asistencia especializada, instalación y operación en el puerto de Chimbote, así como de una planta de lavado y briquetación de los carbones de la citada región del Santa, y la adquisición de locomotoras y material rodante especial para el transporte económico del carbón en el ferrocarril que comunica las minas de carbón con el citado puerto de Chimbote.

May 1, 1957