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By S Mundell, J Armstrong, M Evans

"Automation is a common goal within the coal industry for reasons such as efficiency, reliability and sustainability. However, it requires standards and frameworks so business systems can communicate effectively. Automation of sample analysis processes has been difficult to establish due to a lack of direct business system communication between commercial laboratories and mining companies. This has resulted in manual procedures that have contributed to problems relating to analysis instructions, sample identification, results formats and visibility of status.These problems result in loss of data and confidence in data validity, loss of process efficiency and inability to react to issues. An Australian Coal Association Research Program project (Evans, Armstrong and Arboleda, 2014) has addressed these issues through the Coal Quality Data Exchange methodology for direct business system communication between coalminers and commercial laboratories to optimise the transfer of coal quality data.The benefits to the coalminer of the framework are:increased clarity and auditability of what is being sent to the laboratory and what was requestedreduced potential for error introduced through manual transcription tasksincreased speed of loading of analytical results to the customer Geoscientific Information Management Systemimproved turnaround time for analytical resultsincreased knowledge about what took place in the laboratory with respect to the determination of the analytical resultsincreased visibility of the status of a ‘work order’. The benefits to the technology companies and commercial laboratories is a common framework on which to build a sustainable solution that gets away from the multitude of formats catered for today and time consuming manual processes. The common framework significantly advances the future possibilities for the automation of sampling and analysis processes in a production environment.CITATION:Armstrong, J, Mundell, S and Evans, M, 2014. Automating communications between laboratories and mines – a case from the coal industry, in Proceedings Ninth International Mining Geology Conference 2014 , pp 351–360 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 18, 2014

By Ronald C. W. Webber‑Youngman, Philani Larrance Ngwenyama

Entrapments are a huge risk in underground mines. This happens when miners (or any other persons who have entered underground) survive the initial event of an accident, become trapped or lost in unknown and life-threatening locations after evacuation, and remain unaccounted for. At this point, every second counts, and emergency response is highly desired for any chances of saving survivors. The survival chances of the missing persons depend on how quickly they can be located. Rescue teams are often deployed to search for the missing persons underground. However, the rescue teams are forced to search in random and presumed areas of the mine. This is due to the unavailability of information pertaining to the whereabouts of the missing persons. Not only the provision of accurate locations, but various other types of information such as post-accident two-way communication can enhance the survival chances of the missing persons. This information can be provided by a fit-for-purpose missing person locator system. A wide variety of missing person locator systems are already commercially available, some are in testing phases and others in prototype and development phases. This includes tracking, tracing, location detectors and post-accident two-way communication systems. These systems have unique functionalities, capabilities and limitations; making it difficult for mines to select the most effective, applicable and suitable system specific to their mine. In this study, the user requirements for a fit-for-purpose missing person locator system were developed. The purpose of the user requirements was to provide a guideline to facilitate the system selection process. The user requirements can also be used as a tool to measure and evaluate the performance of the selected missing person locator system. The user requirements were also used to predict the success of the selected system under different missing person incident scenarios. The development of the user requirements showed a potential for many other benefits for missing person locator systems.

Nov 2, 2023

By Roger Evangelista Sánchez

El presente texto analiza la problemática del oro en Madre de Dios a través del informe presentado por el Ministerio de Energía y minas en 1979 donde se debe brindar oportunidad a todo aquel que desee explotar los recursos naturales, sin que afecte el desarrollo normal de sus actividades. El problema se origina como consecuencia de la "Ley de Promoción aurífera" que vive ajena a la realidad del Departamento de Madre de Dios y desaprovecha la tecnología disponible. Para ello, se requiere de una política aurífera donde se busca crear nuevos recursos, considerando el canon al oro, madera, castaña, pago de peaje, aportación económica de los peajes y escala de concesiones de recursos naturales. Asimismo, se debe crear más de 50 mil puestos de trabajo en minería aurífera, la empresa minera del oro, la construcción de un central hidroeléctrica y de una nueva ley aurífera.

May 1, 1980

By Jan C. Still

The Haines-Klukwan-Porcupine subarea of the Juneau Mining District (JMD) is located in the northern portion of the JMD and consists of the land between the Alaska-British Columbia boundary, the Chilkoot Valley, Glacier Bay National Park boundary, and extending south to the Davidson Glacier and the Chilkat Peninsula and Islands (fig A-I). This area was studied as part of the larger JMD study in a cooperative effort between the Alaska Division of Geological and Geophysical Surveys (ADGGS) and the Bureau during 1985 to 1988. Prior to this, during 1984, the ADGGS and the Bureau cooperated in a study of the Porcupine mining area and during 1981 to 1983 conducted separate studies in the area. Field work was conducted by foot, boat, truck, and helicopter. Figure A-I shows the Haines-Klukwan-Porcupine sub-area and shows the areas covered by previous Bureau and ADGGS studies. PHYSIOGRAPHY AND CLIMATE The physiography of the subarea ranges from gentle to rugged. Glaciers formed the major features in the sub-area and left "U" shaped steep walled valleys and rugged mountains. The Chilkat, Chilkoot, Klehini, Tsirku, and Takhin are the major rivers in the subarea. The higher mountains are glacier clad and some valleys still harbor glaciers that reach the valley floors. Lush forests and dense brush predominate up to timberline at about the 2,000-foot elevation. Low point in the subarea is at sea level in the area around Haines while the high point is 7,434 feet at: Mount Henry Clay in the Porcupine mining area.

Jan 1, 2012

By Beatriz Lemos Clemente

A maneira com que acontece a nucleação interfere diretamente na forma dos contornos de grão e também nas propriedades do material em questão. Para visualizar melhor, pode-se utilizar uma célula cúbica, na qual é possível notar que em cada eixo há diferença de textura e densidade entre os grãos já desenvolvidos. Neste trabalho, foram empregadas duas vias de estudo a fim de obter os resultados desejados. A primeira delas é a nucleação homogênea dos grãos e a outra, a nucleação não homogênea, ambas com velocidade constante. Esse fenômeno pode ser visto durante a recristalização de grãos. Rios e Villa [6] criaram um método efetivo para analisar a cinética das transformações homogêneas e não homogêneas a partir do método de JMAK[1-5]. Para comparar método analítico foi desenvolvida uma simulação computacional com base no modelo analítico Rios e Villa [6], foi utilizado a metodologia do Cone Causal (método estocástico). Os gráficos gerados confirmam a teoria de Rios e Villa [6] para esses casos particulares e comparam os resultados obtidos com o conceito de JMAK [1-5].

Oct 30, 2017

By D J. Robinson, L L. Kuhar

"Regardless of orebody value, at some stage, the pit will reach a depth where the reward for mining wider and/or deeper is not justified by the anticipated returns. ‘Last-blast’ strategies may help to some degree in recovering additional quantities of the resource but when a pit remains, there is often significant value left in the ground. In addition, in many cases, one or many good reasons may dictate why going underground and pursuing the orebody below the pit is also not justifiable. Whereas the company can hopefully move on to other more prospective parts of the orebody, the remaining options for the pit are usually very limited. Typically the pit is either held for potentially more favourable future pit expansion opportunities or it could be used for an alternative purpose, such as tailings or waste storage. This paper will present an alternative option that involves the direct extraction of values using in situ recovery (ISR) methods to recover additional value metals from the walls and/or floor of the pit. ISR involves circulating a fluid through the remaining orebody, solubilising the target metal and subsequently returning the solution to the surface for metal recovery. ISR is not the panacea to all but it has been employed selectively in the minerals industry for some time and the production of metals, such as uranium, rely heavily on this approach. ISR is not yet considered by many operators as an approach to compete with open pit or underground mining, largely because of the perceived limitations of this approach and the perceptions of risk. Rapid recent development of tools and enabling technologies relevant to ISR have made us reconsider the most economic approach to extracting many other metals from known mineral systems, even those currently listed as subeconomic. We suggest that ISR has the potential to make mine operators rethink the end of the pit life and adopt an innovative ISR approach to work toward a more complete recovery of value metals from existing pits.Citation:Kuhar, L L and Robinson, D J, 2016. In-pit In Situ Recovery - a New Approach That May Allow for Increased Value Extraction before Pit Closure, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 275–283 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By A N. Danoucaras, S E. Goater, D Hearne, A M. Bansuan

It is globally recognised that existing and emerging mining activities should be conducted in a æsustainableÆ manner for the entire life of mine. Many companies annually publish corporate sustainability reports to demonstrate their actions in accordance with international expectations. This concept of sustainable mining practices also applies to mine water management, with influences often extending beyond site operations, affecting surrounding catchments and community users. This paper explores differences in conceptual and operational terms of æsustainableÆ mine water management within the Philippines. Outcomes of a review of corporate sustainability reports, governance documentation, research programs, and stakeholder knowledge acquired through action-research workshops are presented. The paper aims to inform and support future capacity building exercises delivered by the International Mining for Development Centre (IM4DC), with outcomes tailored to government officials and policy makers of developing countries. The project is funded by IM4DC, which is working with AusAID to identify needs and develop capacity with regard to mining for development; specifically, issues pertaining to governance and regulation, social and environmental sustainability, and operational effectiveness in developing countries.CITATION:Bansuan, A M, Goater, S E, Danoucaras, A N and Hearne, D, 2012. Integrated sustainable water management in mining for development in the Philippines, in Proceedings International Mine Management 2012, pp 205-226 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

Nearly as impressive as the machines that will be on display at MINExpo are the massive engines and tires that keep the machines moving. As you can imagine, it takes a special tire and special engine to run these machines. The following is a look at some of the exhibitors that will be at MINExpo displaying engines and tires. Cummins Inc. Cummins Inc. will display a lineup engines from 37kW to 2,983 kW (49 hp to 4000 hp) at MINExpo, representing the most extensive ?smallest to largest? range the company has ever put on display.

Jan 1, 2012

Q: It is May 1961 at Bill Wrather's Washington house. Bill, think back to your first job after college. Wrather: Perhaps I ought to go back a little bit further than my first job. I entered the University of Chicago with the idea of studying law. My intention was to take a 4-yr liberal arts course and superimpose a law degree on that. But during my undergraduate work I fell under the influence of R. D. Salsbury. He decided I had some talent as a geologist and influenced me to take a geological course. Nevertheless, I did not give up the idea of law. While in school I took a spell of typhoid fever and almost died. The doctor recommended outdoor exercise, so a geological job seemed logical. W. H. Emmons was a graduate student in the University and he interceded with Dr. Hayes of the USGS. I went on the payroll as assistant packer at $60 a month. I had one of the most glorious summers I ever spent in my life. That fall and the following year I took law courses and became thoroughly convinced that I was cut out for a geologist rather than a lawyer. I finished up my law work in 1908 while waiting for a job with Bill Emmons, who was doing a careful study of Goldfield and Tonopah.

Jan 4, 1964

By Daniel Augusto Ferro

O aço 27MnCrB5-2 tem sido muito utilizado para aplicação em facas, além de peças de boa resistência mecânica e resistência ao desgaste, alguns exemplos são verificados no ramo agrícola como faca para corte basal de colheitadeiras de cana, lâminas de roçadeira e helicoide para transporte de grãos. A indústria de beneficiamento de papel/papelão é outro segmento onde esse aço está presente, sendo usado para facas de corte e vinco. Com o objetivo de melhorar a conformabilidade da liga 27MnCrB5-2 no estado temperado, de forma a atender o nível de conformação solicitado, principalmente na fabricação de facas de corte e vinco, foram processados quatro lotes com diferentes conceitos de tratamento térmico de têmpera (martêmpera e austêmpera) para posterior avaliação das estruturas e propriedades mecânicas, a fim de correlacioná-las com a conformabilidade da dobra em cada situação. Com os resultados encontrados e testes práticos realizados durante fabricação da faca de corte e vinco, foi possível constatar melhora significativa na microestrutura/propriedade mecânica/processamento da peça considerando sua conformabilidade com um dos parâmetros de austêmpera utilizados.

Aug 16, 2017

By Koji Matsubara, Yoshiaki Iguchi, Shoji Hayashi

Iron ore particles of a limonite iron ore were reduced completely with H2 at 1023K to 1273K in a fluidized bed. Then, at 973K, the formed iron was exposed to HrH2S mixtures (sulfur activity, as=0.5) for 3.6ks and carbidized with CO-H2-H2S· mixtures at 0.1 MPa. During the carbidization, the particles of about 150mg were sampled at every 600s interval. The sampled particles were analyzed by XRD and chemical analysis for C and S to evaluate the content of Fe3C, Fe5C2, Fe and free carbon. The reaction extent is defined as fo=Xfc3C +xFc5c2; x is the molar fraction of Fe in Fe3C. The carbidization curves can be fitted very well to -ln(l-f0)=g(pb T)t; g(p; T) is the carbidization rate, i.e. the carburization rate on the pore surface of reduced iron. The rate is found to be nearly proportional to the specific surface area of reduced iron, a P 0 , which decreases with increasing the reduction temperature. The value of a P 0 does not change by the carbidization and the stability of the iron carbide product in the atmosphere increases with the temperature.

Jan 1, 2000

By J. Corman

Las Naciones Unidas iniciaron sus actividades dentro de la minería a través de la formación del Fondo Especial que ahora se denomina el Programa de Desarrollo de las Naciones Unidas (UNDP). Antes de la formación del Fondo Especial, la colaboración técnica de las NN.UU. era mínima y se limitaba tan sólo a prestar servidos de asesoría. Sin embargo, su impacto fue mayor debido a factores como los limitados fondos que poseía, el corto período de duración de las misiones, la incapacidad de los asesores de ajustarse a la realidad, la variable capacidad de los asesores y la falta de continuidad. En ese sentido, el presente texto señala el pronóstico de las actividades mineras de las Naciones Unidas después de la Segunda Guerra Mundial respecto al campo de la exploración y etapas técnicas posteriores, así como se muestra los errores de no contar con un apoyo técnico en los inicios del programa de exploración.

Jul 1, 1981

By A. S. Watts

The Bureau of Mines has been conducting an investigation of the feldspar resources of the New England and North Appalachian States with a view to greater efficiency and economy in their utilization. Such an investigation was deemed necessary, not only because of the continued and increasing consumption of these minerals, but especially because of the demand for better technical control of the raw materials that are used by the white-ware industries of the United States. Most manufacturers of white pottery wares have only a limited knowledge of the origin, mode of occurrence, and methods of mining and preparation of the materials that they use. Heretofore, owing to a belief that the supply of raw material was unlimited, the manufacturer had concerned himself chiefly with the solution of the problems of manufacture. Within the past few years, however, it has been found that difficulties arise in manufacture which can be traced beyond the manufacturing process and are believed to be due to a need of better control of the materials used. Furthermore, as competition becomes more severe, more attention must be paid to selection of materials in order to minimize consumption and also to avoid unnecessary expense for transportation of material. Doubtless the lack of interest as regards these details has arisen from the fact that in the past a considerable proportion of the whiteware ingredients has been imported and the manufacturer has been forced to rely on the samples submitted and the general uniformity of the source of supply to insure against variation of the material. An extra precaution arising from this lack of definite knowledge still prevails in the common practice of never depending on one source of supply for anyone ingredient. Often the products of three or more producers are blended so that if anyone shall vary without warning the variation arising from its use will not be sufficient to ruin the ware.

Jan 1, 1916

By Judy K. Todd

Double benching has been utilized as an excavation technique in open pit mines for many years. This process involves drilling, blasting, and excavating the material for the design bench height. A second bench is then excavated without the creation of a catch bench, i.e. only minimal offset from the first bench face is allowed when drilling off the second bench. The result is a double high bench face or double bench. When drilling off the second bench, the offset of the drill from the bench face projects the lower bench face into the pit up to an extra five meters. This reduces the maximum attainable bench angle, enhances the probability of rock escaping the catch bench and increases the overall strip ratio. The generally utilized process of trim blasting also can impact on the final bench profile by contributing to blast damage of the face. BHP Billiton Diamonds Inc., Ekati Mine Diamond MineTM, has pioneered the usage of a technique that eliminates this offset. Double benching is accomplished by drilling a single, 30m pre-shear (two 15m benches) to define and protect the final bench profile. This article provides a comparison of the attained face angles obtained in the field utilizing both of the above methods, as well as a comparison with the analytically predicted angles prior to excavation.

May 1, 2002

By Romeo Calderón

El presente trabajo describe los trabajados realizados en la Compañía minera Huarón con el objetivo de realizar la explotación de vetas muy angostas y sinuosas de potencias inferiores a 1.20 m. de un modo seguro, eficiente y económico, donde fue necesario resolver el problema de carguío y acarreo en tajeos inferiores a 1.20 m. empleando equipo LHD de 0.80 m. de ancho, fabricado especialmente para este fin.

Nov 1, 1982

By Pedro Netto da Silva

O presente trabalho teve como objetivo avaliar a necessidade de substituição das linhas de gás entre a torre de MEA e a entrada no header de distribuição para os vasos Scrubbers em uma plataforma com trinta anos de operação, dado o seu histórico de produção de H2S. Verificou-se a existência de danos possivelmente causados por este contaminante nas tubulações de aço-carbono API GrB e API 5LX 42 pela análise da junta soldada entre flange e tubo, região onde frequentemente ocorrem as falhas na presença de H2S. Observou-se na ZF e nas ZTA a presença de micro-inclusões, as quais foram submetidas à análise química qualitativa por espectrometria dispersiva de raios-X e concluiu-se que eram provenientes do revestimento do eletrodo utilizado no processo de soldagem e da fabricação do aço. Como não foi constatada a presença de trincas ao longo da junta, determinou-se não ser recomendada a substituição de linhas que operam em condições semelhantes.

Aug 8, 2018

By Jo Katembo, Patty Bwando, Patient K. Ilunga, Yves Kalubi, Emman Mulaj

"From 2010, the dolomite concentration in the ore fed to the Usoke Plant increased, resulting in a significant increase in the gangue acid consumption and Mg build-up in the circuit, and thus an increase in the Mg:Co ratio in the plant solutions. This affected the Co salt grade, reagent consumption, filtration and drying capacity. Efforts were put in place to minimise the acid consumption and consequently the Mg dissolution (such as use of pre-diluted acid), but the benefits were negligible. Various efforts were then initiated by CHEMAF to improve the cobalt plant productivity (quantity and quality) by process changes, dual precipitation and seed recycle. The positive results obtained in the laboratory were successfully implemented on plant scale. A change in the process from a single-stage precipitation with Na2CO3 to dual precipitation using a combination of Na2CO3 and NaOH improved the capacity of the Co salt filtration by 30%, the Co salt grade and drying capacity by 50%, and reduced the reagent consumption by 22%. Implementation of precipitate seed recycle increased Mg rejection by 40%, improving the Co salt grade from 20% to 25%, and yielding a further drop in reagent consumption. INTRODUCTION CHEMAF (Chemicals of Africa), a mining company located in Katanga province of Democratic Republic of Congo (DRC), has been operating since 2003. The Usoke hydrometallurgical plant treats the Cu-Co ore from the Etoile pit to produce Cu cathodes via a leach–solvent-extraction (SX)–electrowinning (EW) circuit and Co salt via a selective precipitation process. The plant was designed to treat run-of-mine (ROM) ore grading 6% Cu and 1.5% Co; but, in 2008, due to a decline in grades, a heavy-media separation (HMS) plant was commissioned to enrich the low-grade ROM (3.5% Cu and 0.5% Co) up to 8% Cu and 1% Co before feeding it to the hydrometallurgical plant. Co is recovered by precipitation of Fe and Al with limestone, followed by Co precipitation as Co carbonate using sodium carbonate (Na2CO3), also known as soda ash. 85% of the final effluent from cobalt precipitation is recycled back to the plant as process water; the balance, 15%, is bled out and compensated for by fresh water top up to control and retard the rate of sodium sulfate build up."

Jan 1, 2015

By A Gustafson, D Johansson, K Jonsson

The underground mining process, from in situ characteristics of the unmined rock mass to the final mill product with fully liberated minerals, consists of a chain of unit operations. Some of them influence fragmentation while fragmentation impacts others. From a production point of view, fragmentation is a key parameter for the proper functioning of many unit operations and affects total production; it influences the ability to load, haul and crush the rock later in the process. Fragmentation varies because of rock mass strength, the presence of joints, the chosen explosive, specific charge (kg/m3) and quality of drill holes. The efficiency and result of unit operations such as drilling, blasting, loading and crushing depend on the rock properties, which vary throughout a mine. Generally speaking, operations are not well adapted to the actual rock properties, leading to a non-optimised flow in production. This paper presents the initial part of a project that will build knowledge on the impact of fragmentation on each step of the production chain in an underground mine. It identifies the key parameters of fragmentation, which influence the overall energy consumption and productivity in a mining operation through interviews, mine visits and a literature review. In the subsequent stages of the project, a number of field tests in the case study mine will address important segments of the production process where fragmentation is a major obstacle to improvements. Optimising the entire process, rather than isolated unit operations, will lead to increased productivity, decreased amount of interruptions and lower energy consumption.CITATION:Gustafson, A, Jonsson, K, Johansson, D and Schunnesson, H, 2016. From face to surface – a fragmentation study, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 555–562 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By Manuel Cabrera Melendez

Actualmente las explotaciones en la pequeña minería producen exclusivamente minerales de alta ley puesto que cubre el costo de los fletes y las maquilas, dejando de lado los minerales de alta ley. En esta perspectiva, el texto plantea una alternativa técnica y económica que mejore las condiciones anteriormente planteadas a partir del uso del carbón activado para así beneficiar los yacimientos de baja ley y optimizar el desarrollo minero aurífero de nuestro país. Así también la tecnología del carbón activado reduce los costos de operación puesto que se da una versatilidad del tratamiento de minerales, genera mayor recuperación del oro y mejora su productividad.

Nov 24, 1986

By A. D. McMahon

This survey is one of a series of Bureau of Mines publications designed to serve the needs of Government and industry for comprehensive information on mineral commodities and activities. Copper, a versatile metal, has been vital to all civilizations from pre-historic times to the present. Its essential value in antiquity and until the nineteenth century arose from its malleability and ease of working, its corrosion resistance and durability, its attractive colors in alloyed and unalloyed forms, and, of course, its availability. The principal uses were for tools, utensils, vessels, weapons, pipe, statuary and other objects of art, and for building and architectural purposes where formability, permanence, and beauty were necessary qualities. Utilization of copper based on these physical and mechanical properties has grown tremendously for commercial, structural, mechanical, architectural, and art items; and its capacity for forming numerous alloys has led to a myriad of applications from miniature copper and brass eyelets to huge bronze battleship propellers. The early nineteenth century marks the epoch of the greatest use of copper, transmitting electrical energy. This particular property of copper is fundamental to the spectacular growth of the electrical industry and all associated industries relying on electricity for power, light, and heat. More than half of all copper produced is used for transmission of electricity.

Jan 1, 1964