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By J. J. Gusek

Several final pits in the Seneca No. 1 Surface Coal Mine were abandoned in the 1960's without king reclaimed. In addition, a progressive landslide aggravated by the abandoned mine land conditions was threatening a county mad and private property. An AML-funded project to stabilize the landslide and reclaim the final pits was completed in 1986 for the Colorado Division of Mines and Geology (formerly Colorado Mine Land Reclamation Division). The site was visited after ten growing seasons. The land is stable and the vegetation re-establishment is strong. Volunteer native plant species are now invading the reclaimed sites.

Feb 24, 1997

By Robert Kimutis, Lihong Zhou, Mark Mazzella, Jim Addis

Due to the surge in shale gas production, a substantial number of unconventional shale gas wells have been drilled across U.S. coal reserves. Gas breaches resulting from damaged wells pose a considerable safety risk to miners. This paper investigates how a ventilation system can effectively manage breached gas through a network-based numerical model and laboratory-scaled physical model. Several hypothetical gas breach scenarios in a longwall area are simulated, exploring factors influencing gas mitigation. The study establishes correlations between breached gas inflow and gas concentration at critical locations. The findings in this study provide valuable insights for managing mine ventilation systems and enhancing coal miner safety.

Feb 1, 2025

By R. S. McDonald

Auburn began operations 40 years ago with an office in Sudbury, Ontario, Canada, to provide services to Inco Limited. Over the next 40 years, operations expanded considerably, with projects being undertaken around the world, servicing the smelting and refining industry. Operating bases have been established in Canada, United States, Mexico, Chile, and Spain, with further growth expected to continue with an operating presence in South Africa. The Auburn Group of companies has serviced the smelting and refining industry for over 35 years. Auburn services a variety of metallurgical plants, and our worldwide experience has gathered considerable knowledge on industry processes and maintenance solutions. Today, the ?Business of Smelting? tackles demanding challenges, and operators search for opportunities and solutions to improve smelter maintenance, reduce operating costs, and decrease downtime. The Auburn Group has developed project teams, technologies, and equipment that provide specialised and innovative solutions to the non-ferrous metal industry to help address these challenges. Our Furnace Services team offers a variety of repair and maintenance services for metallurgical furnaces. Our specialised team has proven methods for completing projects quickly and safely. Our worldwide experience includes turnkey project management, construction, and various scopes of work for demolition and refractory repairs on all types of smelting and refining furnaces. Auburn developed the Results FirstTM programme to provide optimized solutions and results for smelter projects. The programme utilises a proven three-step model for improved results for schedule, budget, safety, and ramp-up to production. Our experienced Project Management teams can handle the planning and construction management of capital projects and plant shutdowns. Our projects have involved smelter/refinery modifications, oxygen plant installations, and sulphuric acid plant audits and maintenance. Our Equipment & Products division supplies specialised equipment and products, which are used in the metals industry for plant maintenance tasks. Our capability to design unique equipment, combined with our ability to source products worldwide, makes us a useful resource to find the best-suited equipment to meet the work-site demands. We specialise in custom remote-control units to handle specific maintenance solutions for smelters and refineries, and custom equipment designs for catalyst handling for Acid Plant maintenance. Our extensive knowledge of and experience with industrial technologies allows us to provide a wide range of Industrial Services. These services include vacuuming, high-pressure water blasting, chemical cleaning, pelletizing, dredging, ore bin clearing, roaster repairs, baghouse/ESP services, and manpower supply for both industrial plants and mines. Auburn?s combined strength of personnel experience, knowledge of industry processes, innovative project methods, and equipment technology make Auburn a unique resource for problem solving on every facet of smelter operations.

Jan 1, 2006

By M. England

Test equipment has been developed to record automatically both the displacement of the pile head and the load applied during a conventional maintained load pile test. Some systems also have, in addition, been fitted with the facility for maintaining the applied load, as set by the operator, at very constant levels. The advantages are both commercial and technical, but a well trained operator has to be in attendance to control the test. Since typical test specifications in the UK require more than 19 hours to complete, it became inevitable that at least one equipment operator remained on site to expedite the test for its duration. Although electronic measurement and data logging of load tests may be more safe than previous direct observation of dial gauges. A single person remaining on a construction site alone is not to be recommended, even if they are just supervising the test. Further development of the testing system produced equipment which will perform the entire test specification as required without operator intervention. To achieve this, full automation is employed. The patented method particularly addresses the safety requirements and by using additional sensors, detects any uncharacteristic behaviour of the pile under test or of the reaction system and the equipment takes appropriate action in a controlled and safe manner. The quality of test data returned from these automated systems is a key element when analysing pile behaviour with models such as CEMSOLVE? and TIMESETTM. These analysis methods often indicate ground disturbance resulting from installation technique and have allowed pile design to be optimised using actual field data rather than theoretical considerations alone. An additional feature is remote access, this allows the data recorded to be transferred and the progress of the test to be viewed from practically any location. This permits experts to view the data 'live' and allows rapid diagnosis of any problems with the expected pile behaviour.

Jan 1, 2002

By S. Kamalpour

It has been observed that the productivity of ferromanganese furnaces, and the stability of metal and slag compositions, vary considerably according to the type of coke used as reductant. However, the desired properties of coke for optimum furnace performance are not well understood. In this investigation, the behaviour of four cokes, which exhibited a wide range of performance in ferromanganese production, was investigated by means of laboratory simulations of reducing conditions in the furnace. The Stationary Charge in Controlled Environment (SCICE) technique was used to simulate the conditions in the furnace shaft. Batches of raw materials, mixed in the same proportions as used in practice, were heated at fixed rates to 900, 1100 and 1300°C then cooled. The mass loss was used as a measure of the degree of reduction. Conditions in the lower part of the furnace were simulated by means of melt-reduction experiments in which lumps of coke were drilled out to form crucibles in which enriched ferromanganese slags were reduced at 1500 and 1550°C then cooled. An examination of the raw materials and the cooled, reacted charges using a variety of analytical and characterization techniques enabled the sequence of reaction and changes in morphology of the raw materials to be followed. This enabled an understanding of the behaviour of the cokes during reduction to be developed, which was then used to explain the observed performance of the cokes in practice. By relating the observed behaviour of the cokes in the laboratory tests to measurable properties of the unreacted cokes and to their observed performance in practice, it was shown that to achieve high productivity and good furnace performance, cokes should be selected to have moderately high reactivity towards CO2 (Boudouard reactivity) relative to conventional iron blast furnace cokes.

Jan 1, 2004

By Ferron A. Olson

Natural bornite (Cu5FeS4) leached in ferric chloride or in sulfuric or hydrochloric acid solutions with oxygen showed several differences. In ferric chloride 80 of the copper was leached in two stages. The first (30 copper removal) requiring one minute was controlled by mixed kinetics (liquid ferric ion diffusion and chemical surface reaction). The second was controlled by formation of a surface sulfur layer and then diffusion through the sulfur. With oxygen in sulfuric acid reaction was slow and only the first stage was studied. Copper removal had an induction period. The bornite structure disappeared at 12% copper removal (also found with ferric chloride) and covellite formed on the surface with a species inside the particles having an x-ray structure similar to CuFeS2 but with composition Cu3FeS4 (also with ferric chloride). Copper removal was controlled by iron dissolution. Surface iron vacancies filled with Cu+ to give CuS while interior copper dissolution produced Cu3FeS4. Preliminary results with oxygen and hydrochloric acid showed 80% copper removal and sulfur as end products (similar to ferric chloride).

Jan 1, 1982

By Sandip K. Mukherjee

This report presents the results of the economic analysis of several applicable alternatives to increase airflow in four underground coal mines. Pressure-quantity surveys were conducted underground and measurements were also made at the main mine fan(s). The existing ventilation networks were modeled using the modified Penn State ventilation simulator. The applicable alternatives were simulated. Performance data obtained from these simulation runs were utilized to conduct the cost-effectiveness analysis. The costs for each of the alternatives included capital, operating and maintenance costs. These costs were expressed as annual ventilation costs per active section in terms of dollars per elm taking into account the economic life associated with each of the alternatives. The benefits were expressed as increased airflow quantity in the critical sections. A section of this report also deals with comparison of simulator predicted air quantity values against air quantity values measured underground. The computer outputs for each simulation run are presented in Volume II of this report.

Jan 1, 1983

By Kirsten Corin, Belinda McFadzean, Cyril O’Connor, Jenny Wiese

The Bushveld Complex of South Africa contains almost 90% of the world’s reserves of platinum group minerals (PGMs). In the flotation of PGMs, there are significant challenges arising from the need to treat ever-decreasing grades of the relevant ore deposits. The major challenge in the flotation of these ore bodies is the control and management of the gangue minerals, particularly silicates such as orthopyroxene, plagioclase feldspar, and pyroxene which are often rimmed with talc which makes them naturally floatable. It has been shown that various polysaccharide depressants such as CMC and guar have different properties in terms of depressing the gangue minerals. Since the PGMs are often associated with sulphides, copper sulphate is widely used as an activator in PGM flotation but can inadvertently activate the gangue minerals as well as reduce the recovery of PtTe2 which accounts for up to 40% of the Pt in the Platreef ore body. Depressants also reduce the mass of solids reporting to the froth and can thus destabilise the froth. This effect on the froth can be mitigated by using higher frother dosages or water of higher ionic strength. Reducing chromite recovery is of critical importance since high levels may negatively affect the downstream smelting process. Chromite recoveries can however be reduced through the application of gravity separation or reducing entrainment through reduced water recovery. In summary, due care needs to be taken to carry out site test work to develop an optimum ratio of collector, frother, activator, and depressant to ensure that the highest grades and recoveries of the PGEs are obtained while reducing depressant dosage as much as possible.

By Josué G. Reyes B

El presente texto describe el proyecto de tungsteno en Morococha a través de una breve revisión historiográfica, sus características y composición mineralógica del relave, el proceso operativo y flow sheet, la producción, recuperación, efecto del número de malla y la influencia de flotación de la pirita en los concentrados de separación magnética del tungsteno.

Nov 20, 1978

By L. Xinguang

Shandong MinMetals Corporation, a state-owned import and export organization located in the city of Qingdao, Shandong Province, China, was opened in 1954, with the mission of marketing metal products and industrial raw material in oversea areas for hard currency to support the modernization project of the country as well as the province. The management officers are appointed by the provincial government, and report to the Foreign Trade Department of Shandong Province. Meanwhile, the company also receives guidance from MinMetals head office in Beijing, the capital city of China. The head office does not own and control any provincial MinMetals organizations, but merely coordinate business among provinces.

Jan 1, 1990

By Alain Dorval

"''Purification of marine sands from Les Iles-de-la-Madeleine''This paper presents the results of the work that has been done at CRM pilot plant for «Les Silices du Golfe Inc.». Essentially the purpose of this piloting was to demonstrate, on a semi-industrial scale, the process of purification of marine sands from Les Iles-de-la-Madeleine; that had been developed by CRM Process Development Service. This purification is necessary to produce silica suitable for the glass sand and the foundry sand markets.Introduction«Les Silices du Golfe Inc.» is a company who intends to dredge marine sands around the «Les Iles-de-la-Madeleine» coasts. The material will be transported to Gaspesia where electricity, water supply, and a convenient site is available to treat it. A high purity silica intended for glass sand and foundry sand markets will be produced. The objectives of this purification process are to remove organics, calcium, feldspars and iron.Material ReceivedCRM received 50 tons of sand with Si02 varying between 80,6 and 99,3 % (see Figure.1). The highest variations in impurities were the calcium and lost on ignition. We notice direct relation between% SiO2, % CaO and % L.O.I. as you can see on the following Figures 2, 3 and 4."

Jan 1, 1994

By Robert W. Bruhn

An investigation was male of ground response to pillar retreat mining in a 1.7 meter thick seam at 108 meter depth at a site in northern West Virginia. This paper describes mining-related stress changes and movements at nine level, displacements within the overburden, ground surface subsidence and groundwater level variations. Subsidence approached 40 per cent of the nine height ad continued more than a year after mining. Water levels declined la certain deep-lying strata.

Jan 1, 1984

By D. A. Norrgran, J. A. Wernham, D. E. Walsh

A qualitative test program was sponsored jointly by the University of Alaska and Eriez Magnetics, in order to study placer gold nugget recovery using an eddy-current separator. Various gold nuggets from Alaska, ranging from 6.4 mm to 63.5 mm in size, were tested. All testing was performed using an Eriez Laboratory ESC, Model REA, fitted with 2000 gauss, surface field strength magnetic rotor. The belt speed was set to 91 meters per minute and the rotor speed was set to 2500 rpm in the forward direction. The splitter was adjusted to just reject the largest pieces of rock that measured an average 76 mm x102 mm x 127 mm. Based on the results of this limited test work, it can be recommended to placer gold mine operators, that Eriez Magnetics ECS technology is a viable and practical concentration technology for coarse gold recovery. Silver and platinum were also tested.

Jan 1, 2003

By F. Hassani, R. Mikaeil, B. Ferdowsi

Two analytical solutions for estimating the ovaling deformation and forces in circular tunnels are widely used in engineering practice, due to soil-structure interaction under seismic loading. This paper discusses the discrepancy between the two analytical and finite difference methods. A comparison of the two analytical methods shows that the calculated forces and displacements are identical for the condition of full-slip between the tunnel lining and ground. However, the calculated lining thrusts differ by an order of magnitude when considering no-slip between the tunnel lining and the ground. The analytical solutions are compared to numerical analyses of the no-slip condition using the finite difference method to validate which of the two methods provide the correct method. To achieve the goal, numerical modelling, field data of the Kuhin railway tunnel and Manjil earthquake characteristics are used. Numerical analysis results agree with one of the analytical solutions that provides a higher estimate of the thrust on the tunnel lining, thus highlighting the limitation of the other analytical solution.

Jan 1, 2008

By Alessandra Savazzini dos Reis

A crescente preocupação em relação às áreas de proteção ambiental e ao alto consumo de argila, matéria-prima da cerâmica vermelha, ocasiona a indisponibilização progressiva de reservas de argilas no Brasil. Com isso, vê-se a necessidade de incorporar resíduos na massa argilosa para confecção de produtos de cerâmica vermelha. A indústria de cerâmica vermelha brasileira consome cerca de 10 milhões de toneladas de argila ao mês para produção de telhas e blocos. Na própria olaria são gerados resíduos, tal como, o resíduo de massa cerâmica crua originado na etapa de conformação das peças. Este trabalho visa incorporar o resíduo de massa cerâmica crua na massa argilosa usada em cerâmica vermelha. O resíduo foi caracterizado por meio de ensaios de FRX, DRX, limites de Atterberg e distribuição de tamanho de partículas. Corpos de prova feitos com massa argilosa e resíduo em teores variando de 10% a 90% (massa) foram conformados, secos à 110ºC, queimados à 900ºC em forno industrial e submetidos a ensaios de absorção de água, porosidade aparente, massa específica aparente e resistência à compressão. Os resultados evidenciaram que as propriedades cerâmicas avaliadas nos corpos de prova da massa argilosa incorporada com o resíduo atendem aos valores das argilas-padrão brasileiras para cerâmica vermelha.

Aug 17, 2017

By William J. Krisko

This contract final report summarizes the design, fabrication and testing of a "line brattice air curtain" device under Bureau of Mines Contract H0357097. The purpose of this program was to develop the concept of using an air curtain for coursing ventilating air parallel with the air curtain From the last open crosscut to the face in exhausting ventilation systems to replace the line brattice cloth in room and pillar coal mining operations. The final design of the air curtain device consists of a 10-foot long closed end pipe with c: slot cut along its length. Pressurized air is delivered to the open end with a hydraulically-driven blower. A sheet of air emanates from the slot and is directed toward the mine roof. An invisible sheet of air is thus created between the top of the machine and mine roof and acts a an extension of the existing conventional line brattice.

Jan 1, 1977

By Ashis Bhattacherjee, Bijay Mihir Kunar

A literature review on quantitative analysis of mine safety studies revealed that investigators use a wide range of statistical techniques for the analysis of mine injury data. Researchers have addressed the various issues of accident causation and prevention through analysis of mine injury data collected from mines. These studies are generally based on historical accident/injury data without considering the injured person/population at risk. In this paper, a public health approach, based on scientific methods of epidemiology, is presented to address mine safety issues. Epidemiology is the scientific study of disease and injury patterns among populations in time and space. Originally, epidemiology was concerned with epidemics of communicable diseases. Then it was extended to non-communicable diseases. Safety researchers found that epidemiologic methods are the best tools for injury research, because the occurrences of injury and the occurrences of disease are quite similar. As a result, some researchers started applying this concept to injury research. This paper presents some of the techniques used in epidemiologic studies and illustrates the application of a case-control study design to evaluate the role of some risk factors associated with injuries in underground coal mines. In this study, the injured persons were identified and, simultaneously, interviews were conducted to find the significant risk factors responsible for occupational injuries in coal mines.

Jan 1, 2011

By Jeremy P. Doolan, Leigh B. Neindorf, Geoff W. Capes

The development and use of rock mass classification tools have been a key component for improving stope design over the past 4 years at the Xstrata Zinc George Fisher Mine in northern Queensland, Australia. In 2003, stope extraction data from 3 years of open-stope mining provided an excellent situation to review the assumptions in the feasibility study. Extracted stope profile information, drillhole geotechnical data, underground observations, and oral and written communication were used to develop a thorough stope reconciliation performance database. With-out collecting the back analysis data and presenting the data in a usable format, engineers are left to debate opinion instead of engineered judgment. This can lead to biased and uninformed design parameter choices with the potential to repeat poor design. This paper demonstrates some effective, practical examples of empirical data collection where rock mass classifications tools were developed and used to create improved confidence in predicting stope stability and failure profiles. The work contributed to design changes that resulted in a reduction in stope hangingwall dilution and an increase in head grade while continuing to ramp up production from 2003–2005.

Jan 5, 2007

By Paul Zinner

Efforts to win an enriched manganiferous product from the Missouri Valley deposits of South Dakota have included an application of most known ore-dressing devices and have been largely unsuccessful. At least two methods showed some promise of success and were the subjects of detailed Investigation by the Bureau of Mines during the period from July 1945 to August 1947. A series of mining and beneficiation tests were undertaken to determine conditions under which the most feasible concentration methods could be employed and to define the limits of such applications in terms of the character of the final beneficiated product. In the absence of a significant current market for any conceivable product of beneficiation, the extent to which applied methods might be considered successful was measured in terms of ratios of recoveries to grade, regardless of the adaptability of such beneficiated products to further metallurgical or direct usage. The results of all investigations show that production of a shale-free, concretionary, manganese-bearing product by any known method requires great sacrifices in manganese recovery. Products of beneficiation, with specifications permitting some inclusion of shale, can probably be most effectively produced by methods employing specialized jigging equipment as the principal functional unit of a process.

Jan 1, 1949

By J. S. Moretzsohn, D. F. Graham

"Airborne Synthetic Aperture Radar (SAR)was acquired over the Carajás Mineral Province, within the rainforests of the Amazon, which hosts the world’s largest Fe-ore deposit(Santos, 1986). Significant chemical weathering exists in this humid environment. PrevalentAu mineralization is thought to be generally associated with deformation zones in Archean schists.Radar data have proven to be very useful as an aid to geological mapping in the tropical rainforests of the Amazon Basin in Brazil. In these densely vegetated areas, a sense of regional structural trends is obtained as a con-sequence of the sensor/terrain geometry. The top forest canopy is the main terrain reflector of X-band radar energy, and consequently is the main terrain surface feature expressed in processed radar imagery. Radar is important for extending t,he continuity of mapped structural lineaments. Differential weathering is related to variations in radar image texture which is used to infer gross lithologic variations and relative age relationships of major rock units. Specifically, quartzites and banded iron formation are highlighted in the radar imagery due to their unique tonal and textural appearance, in contrast to schists, gneisses and metavolcanic rocks. As tropical areas are typically enveloped in cloud or mist, radar data are invaluable in providing information for logistical planning of field mapping activities."

Jan 1, 1997