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The applicability of borehole assaying techniques, both conventional and advanced, to orebody evaluation in the mining industry is reviewed and assessed, and the research, development, and demonstration programs necessary to apply the various logging techniques to mining are outlined. At present, the principal method of orebody evaluation in the mining industry is coring. However, coring is costly and time-consuming, and potentially great savings can be realized if all or part of d coring program is replaced by a borehole logging suite specialized to the needs of the particular mining industry. Using a set of 12 minerals, most of which are essential to the U. S. economy, an algorithm is presented for calculating the priority of developing suitable borehole assaying technology to replace all or part of the coring in each mineral industry, The priority is expressed in terms of dollars currently spent for that portion of present orebody evaluation techniques which may eventually be replaceable by in-situ assay techniques. The orebody assay requirements (grades, accuracies, etc.) of the 12 selected mineral industries, as determined from mining industry interviews and published literature, are compiled and represent performance criteria for borehole assaying instruments for the particular industry. Current logging techniques, applied chiefly in the petroleum industry, and advanced assay techniques which are or may be packageable for borehole use are evaluated to determine their performance characteristics. The performance characteristics of the various conventional and advanced techniques are then compared with the performance criteria in each of the 12 mineral industries in order to determine the potential benefit derivable from each technique. Finally, the benefit available from each technique, averaged over the 12 mineral industries, is compared with the cost of development of the technique, to determine the overall priority for investment in research to develop the technique for use in mining. The technology assessment and cost-benefit analysis shows neutron activation analysis in its various forms to have the highest priority for research and development as a borehole logging technique. Other techniques found to be promising include x-ray fluorescence, x-ray diffraction, photoluminescence (optical fluorescence), and infrared spectroscopy. Of the 12 industries considered in the study, those where the need for advanced borehole logging technology is greatest are uranium, copper, gold, and iron.

Jan 1, 1976

This Bureau of Mines publication consists of an overview of the mine waste management research currently being conducted by the Bureau. The following papers, given at a Technology Transfer Workshop, emphasize the increasing importance of research related to the safety and environmental considerations of mine waste disposal In recent years. Current work related to legislation passed in the last 10 years and their subsequent standards includes the development of adequate monitoring systems, development of stability and seepage prediction and control techniques, control of runoff water, and control of leaching solutions. Selected topics are included here that cover coal mine waste disposal, embankment slope stability monitoring, flow failures of mine tailings impoundments, and controlled burnout of abandoned coal mine fires. The projects described provide a current documentation of problems being addressed.

Jan 1, 1981

By John R. Craynon

Science and Sustainable Development Each of the ?pillars? of sustainable development are directly impacted by mining. We need science to understand exactly how mining contributes to each. Overview of presentation ? History of mining and sustainable development ? Role of stakeholders in measuring/accepting contributions of mining to SD ? Identified ?shortfalls? in understanding mining and SD ? Science needs

Aug 1, 2013

By Paul Meadows

This Bureau of Mines report presents operating practices and results of pressure maintenance and secondary recovery by water injection or by water injection supplemented by gas injection. Particular emphasis is placed on the results of water injection, which is the principal oil-recovery method employed in projects covered by this report. No attempt is made to study gas-injection projects or operations that are considered water-disposal projects. Also, this report does not include water-injection projects that have not been in operation long enough to evaluate results. Figure 1 is a map of north Louisiana showing the geographical locations of the projects included in this report. Most of the data used in this study were supplied by unit operators, operating companies, and the Louisiana Department of Conservation. Reservoir information and recovery data are generally those supplied by the operators, but include revisions where deemed necessary.

Jan 1, 1962

By J. A. López-Molina, S. García, V. Castellanos-Pedroza

"Grouting aims to reduce the permeability of rock mass below a predetermined value and has been widely used in rock engineering field for a long time. However, the injection procedure needs several empirical decision makings and it is rather difficult to reliably confirm the achievement of improvement, because the grout penetration process is not sufficiently clarified. This investigation proposes a neuronal method of defining spatial distribution of rock hydraulic properties and a fuzzy scheme for estimating their relation with the grout penetration (consumption, localization and filling material). The intelligent method stands as a tool for helping in harmonizing the sealing activities and the medium conditions. The virtual simulation of grouting strategies embraces geology, hydraulic and rock characteristics and the filling process. Important aspects as different pressure injection levels and fracturing systems can be holistically studied using the intelligent environment, resulting in an advantageous, economic, flexible and interactive tool for planning better this critical activity.INTRODUCTION Grouting is a very common method of sealing rock and repairing concrete structures (Butron et al., 2010) and its use in engineering of dam-foundation and tunneling has been documented as very successful (Yang, 2004). Generally speaking, to achieve the closing purpose, boreholes are drilled into the rock mass and grout is injected (under pre-selected pressure) until the fractures around the borehole are filled. The complete filling of these fractures is possible if they are connected to each other in such a way that the remaining water and air can be displaced outside the designed grouting zone (Houlsby, 1990; Kutzner, 1996). Water testing is necessary for evaluating seepage potential and for determining whether grouting is necessary or practical. Regardless of the main reason for the investigations, design of a program for water testing for grouting should consider the type of structure to be built, the geologic conditions at the site and the level of seepage control desired. As information gathered the report must content the fracture openness, number and connectivity, exploratory drill holes orientations, materials situation and a panorama of rock-mass state (quality)."

Jan 1, 2015

By P. H. Williams, D. J. Morris

The co-disposal of coarse and fine coal wastes by combined pumping through a pipeline to subaerial deposition was pioneered in Australia in 1990 by Jeebropilly colliery in Queensland. Significant segregation of fines is found to occur in its co-disposal delta, leading to the formation of distinct mainly coarse upper and fine-dominated lower segments; the upper delta drains rapidly and is able to support traffic on its surface immediately after deposition. An existing theory of subaerial deposition, originally developed for mine tailings alone and later extended to trial co-disposal, is shown to apply also to the upper segment of the full-scale Jeebropilly delta

Jun 19, 1905

By Asmo Vartiainen

Background of Direct-to-Blister Flash Smelting is discussed; especially slag chemistry relating to copper solubility, slag fluidity and impurity behavior. In December, 2000, Mini-pilot Flash Smelting test runs were carried out at Outokumpu Research Oy to produce blister copper from Chilean concentrate and white metal and from a mixture of them. Tested slag types were iron silicate slag, ferrous calcium silicate slag and calcium ferrite slag with different slag compositions and different concentrate/white metal ratios. The test runs were successful. The fluxing effect of copper oxide was clearly demonstrated and ferrous calcium silicate slags remained fluid on a very wide liquidus range. The distribution of arsenic between ferrous calcium silicate slag and blister copper is much higher than between iron silicate slag and blister copper. This successful test run with the new slag type offer new possibilities in Direct-to-Blister process design.

Jan 1, 2003

By J. B. Clemmer

This report summarizes the results of u laboratory study of the beneficiation of Arkansas bauxite by flotation. Although the investigation is not yet completed, a preliminary retort of the results on several typical bauxites is presented to show the merits rind. limitations of flotation for the production of concentrates acceptable to the aluminum industry. It is

Jan 1, 1941

By J. B. Clemmer

This report summarizes the results of u laboratory study of the beneficiation of Arkansas bauxite by flotation. Although the investigation is not yet completed, a preliminary retort of the results on several typical bauxites is presented to show the merits rind limitations of flotation for the production of concentrates acceptable to the aluminum industry. It is

Jan 1, 1941

By J. C. Ashby

Electric utility response to certain amendments of the Clean Air Act has resulted in a production of several types of alkaline coal combustion byproducts. Alkaline combustion byproducts are gaining increasing usage for acid mine drainage mitigation as research leads to a better understanding of their beneficial applications. Since January of 1997, Mettiki Coal Corporation has been injecting alkaline flue gas desulfurization material from Virginia Power's Mt. Storm Unit #3 wet limestone scrubber into abandoned portions of the active Mettiki mine. This paper provides an overview of the key design, transportation, regulatory, and environmental issues faced in the project.

Jan 1, 1998

Sluice box operating practices in Papua New Guinea (PNG), and published work on sluice boxes are briefly reviewed. Some recent work on sediment entrainment mechanisms occurring in sluice boxes have also been described. In the light of this information, some drawbacks in the commonly adopted sluice box operating practices in PNG, and ways of overcoming them, are also highlighted.

Jan 1, 1991

By H. B. Carroll

This Bureau of Mines report evaluates the performance of commercially available portable instrumentation for the detection of carbon monoxide, carbon dioxide, oxygen, and methane at conditions simulating an industrial work atmosphere. Portable instrumentation included in the study was gas-detection tubes (length-of-stain and color intensity), catalytic detector, liquid absorption detectors, paramagnetic oxygen detector, galvanic detector, and pelement or hot-wire methane detectors. Evaluation of the instruments was in atmospheres with 50 and 80 percent relative humidities at 75° F and containing test gas concentrations of 0.1, 0.25, 0.50, 1.0, 1.5, and 2.0 times the thresh-old limit value. Correlation of the results from the portable gao analyzer with measurement from the standard instruments was made by calculating and plotting an estimated line of regression, prediction, and confidence limits and the correlation coefficient for each detector system. Relative humidity in the 50-to 80-percent range did not appear to contribute to instrumental uncertainties in either performance or operation. Considerable deviation in detection precision between the portable gas-detection systems and the standard systems was established, especially at the lower gas concentration levels. The main difference or inconsistency in toxic gas concentrations determined with length-of-stain tubes resulted from the observer's interpretation of the results rather than difference in the tubes themselves.

Jan 1, 1973

By P. A. Olubambi

The leaching of zinc and copper from Nigerian bulk sulphide ore with sulphuric acid in the presence of hydrogen peroxide was studied. The aim of the study was to investigate the effectiveness of hydrogen peroxide as an oxidant for the sulphuric acid leaching of zinc and copper from a complex sulphide ore. Distribution of elementals within the various particle sizes was initially determined by ICP-OES and XRF to provide a basis for explaining the dissolution process. The effects of concentration of hydrogen peroxide, particle size, stirring speed, and leaching time at a constant temperature of 298K were studied. There were variations in elemental and mineralogical composition within the different sizes. The concentrations of zinc and copper reduced as particle size decreased while silica, sulphur, iron and lead contents increased. Dissolution results showed that the leaching rate of copper was lower than that of zinc. The highest recoveries of zinc and copper were obtained at a leaching time of 180 minutes, stirring speed of160 rpm, particle size of 75 µm and a concentration of 1M H2SO4/1MH2O2. It was observed that the leaching rate of zinc and copper increased with increasing hydrogen peroxide concentration. Increased stirring speed had a negative leaching effect as it promotes hydrogen peroxide decomposition. Keywords: Nigerian sulphide ore, zinc, copper, hydrometallurgy, sulphuric acid, hydrogen peroxide.

Jan 1, 2006

By P. A. Olubambi

The leaching of zinc and copper from Nigerian bulk sulphide ore with sulphuric acid in the presence of hydrogen peroxide was studied. The aim of the study was to investigate the effectiveness of hydrogen peroxide as an oxidant for the sulphuric acid leaching of zinc and copper from a complex sulphide ore. Distribution of elementals within the various particle sizes was initially determined by ICP-OES and XRF to provide a basis for explaining the dissolution process. The effects of concentration of hydrogen peroxide, particle size, stirring speed, and leaching time at a constant temperature of 298K were studied. There were variations in elemental and mineralogical composition within the different sizes. The concentrations of zinc and copper reduced as particle size decreased while silica, sulphur, iron and lead contents increased. Dissolution results showed that the leaching rate of copper was lower than that of zinc. The highest recoveries of zinc and copper were obtained at a leaching time of 180 minutes, stirring speed of 160 rpm, particle size of 75 µm and a concentration of 1M H2SO4/1MH2O2. It was observed that the leaching rate of zinc and copper increased with increasing hydrogen peroxide concentration. Increased stirring speed had a negative leaching effect as it promotes hydrogen peroxide decomposition. Keywords: Nigerian sulphide ore, zinc, copper, hydrometallurgy, sulphuric acid, hydrogen peroxide.

Jan 1, 2006

By J. H. Adkins

The goal of this program was to produce a set of baseline health and safety training materials that could be used by the metal/nonmetal mining industry to reduce injuries and to comply with federal training requirements. The materials developed are arranged in a two level outline format. The first level provides the title, course goals, background and topical outline while the second level provides a detailed outline of the course content. Visuals, designed to portray miners in a positive, attractive fashion, were done in simple line drawing so they would reproduce for handouts without loss of quality. Each of the required units in the Baseline Guides have one or more self-checks. These are designed to be suggestive of evaluation techniques the users can develop for themselves. An instructors guide and a mining terms glossary are included. In a second phase the program developed performance based training guides for Annual Retraining and Experienced New Hires in the Underground Salt Industry.

Jan 1, 1983

By Bjarne Ekberg

"The most economical way of dewatering mineral concentrates is to reduce the moisture content in the material mechanically using thickeners and filtration avoiding thermal drying whenever possible. In addition to this, the dewatering process should produce low moisture cake, high quality liquid, consume little energy. As a part of the dewatering process The CERAMEC® capillary filter has been proven to meet these requirements in over 150 installations. The filtration is done by using ceramic filter plates with small pore size. The capillary action in the filter medium secures gas free filtration at good vacuum, and due to the small pore size, filtrate is crystal clean and particle free. The energy consumption is minimal. This paper will discuss results from filters installed at Pyhäsalmi Mine Oy in Finland where the technology was has been used since the late eighties. Results from more recent installations like Los Pelambres in Chile and LKAB in Sweden will also be discussed.INTRODUCTIONThe idea of using capillary action to make dewatering more efficient was invented two decades ago. Ten years later whole filter plants utilizing the new method were delivered to mine concentrators for dewatering of mineral concentrates. Further development of ceramic membrane plates made it possible to meet the requirements in iron ore dewatering. In addition to low cake moisture, high capacity and low energy consumption, there are a lot of environmental advantages in using capillary filtration. One of them is clear filtrate.CAPILLARY FILTRATIONA micro-porous filter material behaves like a large number of narrow capillaries forming a network. When a pressure difference ?P is applied over the wetted, hydrophilic pore with the radius r, the force striving to push the water out of the pore will be ?Ppr2. The force striving to hold the water in the pore will be the vector force 2pr? cosa of the surface tension ? and the cosine contact angle a. Equalling those forces and solving the equation for ?P we get"

Jan 1, 2003

By Kevan J. R. Ford, Chris A. Fleming, Robert D. Henderson

"Kinross Gold Corporation’s Maricunga mine in Chile presents an ideal opportunity to apply the SART process to a heap leach operation. Given increasing levels of cyanide complexed copper in current pregnant solutions from Maricunga heaps (over 300 ppm Cu), there is a need to reduce these levels and decrease cyanide consumption and cost. Additionally, a means of disposing of this copper is required, preferably as a saleable product. The well published SART process applied to gold-copper cyanide solutions was selected as it allows rapid precipitation of cyanide soluble copper as a relatively pure copper sulphide. The process also allows effective recovery and recycle of cyanide back to the heap leach operation.This paper reviews the SART process chemistry and presents a summary of SART bench-scale and pilot plant testwork completed by Kinross. Key design parameters and engineering aspects of the proposed plant at Maricunga are discussed. SART plant operating costs and net revenue analysis are included and illustrate the compelling economics of installing a SART process plant. INTRODUCTIONMaricunga OperationCompañia Minera Maricunga (CMM), fully owned by Kinross Gold Corporation, operates the Maricunga mine (formerly Refugio) which is located 120 km due east of the city of Copiapó at an elevation of 4,200m above sea level in the Andes mountains of northern Chile. Figure 1 shows a map of the location of the Refugio mine relative to other gold and copper mines in the region."

Jan 1, 2008

By R G. Richards

The Australian glass sand industry produces some 2.8 million tonnes per annum of silica sand, of which about 2.0 million tonnes are exported and the rest is for the domestic market. Approximate production rates for each Australian state are listed. The variety of processing methods used in the currently exploited deposits reflects the size, location, and characteristics of the various deposits and the requirement of the end market/s. The industry uses to a large extent equipment developed for the separation of mineral sands, particularly as it applies to low grade heavy mineral deposits, where low cost, high capacity and metallurgically efficient equipment has proved eminently suitable for the production of the low value glass sands. The requirements of the domestic market, as well as those of the present and potential export markets are discussed covering quality requirements, distribution channels and other factors critical to success.

Jan 1, 1990

By S. J. Aresco

The Bureau of Mines has been active in promoting the purchase of coal for Government use under specifications that define the requirements in terms of heating value of the coal, expressed in British thermal units, and the composition as shown by proximate analyses. To these, when required, are added the ash-softening temperature, the free-swelling index, and the Hardgrove grindability index. Under most of these specification contracts the bidders guarantee the quality of the coal, and that guaranteed by the successful bidder becomes the standard of his contract. The deliveries are sampled in accordance with instructions4 issued by the Bureau of Mines; the samples are analyzed in the Bureau laboratory to determine whether the coal is of the quality guaranteed by the contractor; if it is not, a price adjustment is made. Analyses of the delivered coal and tipple samples (samples collected at mine tipples as coal is being loaded into railroad cars or trucks) provide valuable data for use in evaluating future bids. In addition, the continuous sampling of coal as delivered is a check on the practical results obtained in burning the coal.

Jan 1, 1966

By Edelink Efrain Tinoco Falero

Na atualidade a produção e a utilização de DRI estão aumentando nos países desenvolvidos, principalmente devido à redução do preço do gás natural e do sucesso da nova tecnologia de extração de gás de xisto. Os custos operacionais e os problemas ambientais são, efetivamente, os fatores tecnológicos importantes a serem considerados na otimização da produção de DRI. Portanto, o teor de carbono do DRI tornou-se essencial em virtude da capacidade de gerar energia química no banho de aço, complementando assim a eletricidade em FEA, e as contribuições exotérmicas da oxidação de Si e C nos conversores LD. Este trabalho faz parte de um programa completo de cooperação entre a companhia de mineração Samarco e o Grupo de Siderurgia da PUC-Rio, lidando com as equações cinéticas da metalização e carburização simultânea em fornos de redução direta. Para este efeito, o reator foi dividido em três zonas internas: Redução, Transição e zona de resfriamento. Além disso, também foram consideradas três regiões concêntricas: periférica, média e centro. Á partir desses resultados, para um tipo de pelotas RD específico, mistura de gases utilizados nas instalações industriais e similar flui-dinâmica do processo, as equações cinéticas de metalização e carburização foram estabelecidas para cada zona. Um programa computacional METCARB, totalmente baseado nessas equações cinéticas, foi então concebido. Finalmente, uma validação adicional procedeu-se tendo em conta duas corridas operacionais industriais.

Aug 17, 2017