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By Sidney Katell

This cost bibliography, covering the period from January through December 1960, is a continuation of the series which began with the publication of Information Circular 7516 in October 1949. It is also the second report in the series to be prepared as a cooperative effort by the Bureau of Mines and the American Association of Cost Engineers. The cooperative agreement between the two groups provides for the publication of an annual bibliography with the work load involved in the preparation shared equally. The abstracted articles, concerned with all facets of cost engineering in the field of petroleum and chemical plants and related facilities, came from the following sources: 1. Bureau of Mines Information Circulars. 2. Bureau of Mines Report of Investigations. 3. Chemical Engineering. 4. Chemical Engineering Progress. 5. Chemical Week. 6. Coal Age. 7. Coal. Utilization. 8. Cost Engineering. 9. Industrial and Engineering Chemistry. 10. Nucleonics. 11. Oil and Gas Journal. 12. Petroleum Engineering. 13. Petroleum Refiner. 14. World Oil.

Jan 1, 1961

By Günter Huber, Bruno Mattle, Helmut Westermayr, Daniel Spöndlin, Max John, Nejad Ayaydin

PROJECT DESCRIPTION Alignment The Strenger Tunnel forms part of the S16 four-lane expressway between Landeckand Bludenz. The construction of this important East-West connection started in 1973with the Arlberg Road Tunnel as its key constituent. Beginning in 1992, solutions for the section between Pians and Flirsch were investigated. Efforts to conserve nature and to avoid potential avalanche and landslide areas led to a solution detouring the villages in the Stanz valley. The starting points were predetermind by the intersections at Pians in the East and at Flirsch in the West. As a result of the expected traffic load and the comparatively high gradient of 2.9%, both one-way, two-lane tubes were constructed at once. The north tube is 5.851 m long, the south tube 5.775 m, see Figure 1. Layout of Tunnel Cross-Section The tunnel cross-section was determined by 2 × 3.75 m wide, 4.70 m high roadways, two sidewalks and sufficient space for two fans above the clearance

Jan 1, 2005

By Virgil A. Marple

The objective of this contract was to conduct characterization, evaluation and/or calibration studies of instrumentation used for measuring the quantity of respirable dust in mining atmospheres. Initially, this work involved the upgrading and detailed evaluation of the aerosol test chamber and the development of impactors with respirable classification characteristics. These were used as standards in the chamber for measuring the quantity of respirable dust based on either the ACGIH or BMRC respirable dust criteria. A program was then conducted to calibrate several photometers. In addition, the mass sensitivity of the GCA RAM-1 photometer to water droplets in the respirable size range was determined. Three additional studies were also made in this program. First, an experimental study was performed to ascertain the effect of crosswind, cyclone orientation and particle size on particle sampling and penetration through the 10 mm Dorr-Oliver cyclone. Second, a theoretical study was conducted to refine the theory used to predict the particle collection characteristics of impactors. Third, filter samples with known quantities of diesel and coal particles were produced and delivered to the B. of Mines for testing a Raman scattering analysis technique to discriminate diesel particles in the presence of coal dust.

Jan 1, 1984

Three methods of gold analysis are briefly described highlighting some of the problems and advantages of each. The variation of results between samples and splits and due to method of preparation is illustrated. The mean per cent difference of the fire assay values from the means of sample split values for three cases is 15 per cent.Finally, a comparison of the aqua regia leach atomic absorption spectroscopy (AAS) and fire assay fusion AAS techniques is made.This shows that the mean precision, the ability to obtain the same value, of the methods at 98 per cent confidence is ± 30 per cent and ± 15 per cent respectively. The fire assay fusion AAS method is relatively more accurate than the aqua regia one.

Jan 1, 1984

By Herbert H. Einstein

The thrust of research reported in Part I was to collect in-situ data from exploration programs and the published literature, and to empirically establish distributional patterns for these variables. Since discontinui¬ties in a rock mass govern to a large extent its engineering properties and thus the performance of any slope in the mass, work has been devoted to determining the appropriate distributional forms for attitude spacing and length of discontinuities and to distributional properties of resis¬tance and deformability parameters. The conclusion from these analyses is that trace lengths are logNormally distributed and that joint spacing is Exponentially distributed, regardless of orientation of the sampling line, and regardless of whether each joint set is considered separately or not. Joint orientation (attitude) data representing 22 individual joint sets from eight sites (a total or approximately 20,000 joints), do nor strongly support any of the commonly used distributions as broadly applicable in practice. The autocorrelation )f geometric joint properties is also examined. However, no significant spatial correlation could be found even after extensive data manipulation. The investigation of resistance and deformability parameters starts with a review of mechanisms and models that are used to represent them. Review and statistical evaluation of approxi¬mately 2,000 discontinuity shear tests has shown that good statistical estimates for use in reliability analyses can be obtained for friction angles.

Jan 1, 1979

By John D. Spencer

Clean energy production from coal, oil, and gas, and the development of these and other energy sources continued to be a major objective of the energy research program of the Bureau of Mines.3 In 1971 increased emphasis was placed on the production of fluid fuels and chemicals from coal. Advances were achieved in the development of the Synthane and Hydrane gasification processes for producing pipeline gas from coal (page 31), and progress was made in research on solid wastes utilization (page 2), and on liquid fuels production from coal (page 37); Coal mine safety, solid waste disposal and utilization, coal preparation and transport, and fundamental research on coal and related products also continued to be the subject of extensive research. Improved methods for extracting petroleum and natural gas without surface and subsurface pollution featured research on these vital fuel and energy sources. This research was highlighted by studies of the fracturing systems of reservoir rocks, including subsurface fracture mapping and new fracturing techniques to achieve optimum production of oil and gas (page 52). Of equal importance were projects on oil recovery by water or gas flooding (page 52), by steam injection (page 57), on the identification of oil spills (page 63), and on means to reduce vehicular exhaust emissions (page 66).

Jan 1, 1972

By Jack Zhang, Yunguo Tang, Baodong Zhao

"Rare earth elements (REEs) have numerous key applications in both traditional and advanced technologies. A shortage of some critical REEs is expected due to the discrepancy between the REE abundance in REE deposits and the REE demand from the market. For example, Neodymium, Europium, Terbium, Dysprosium, Erbium and Yttrium are expected to be in short supply. REE recovery and separation from secondary resources such as uranium wastes, heavy mineral sands, and recycled materials can balance the shortfall in a cost effective way.The Saskatchewan Research Council (SRC) is engaged in the development and commercialization of complete REE recovery and separation technologies in Canada. One of SRC’s newest developments is the design and commissioning of a heavy rare earth (HREE) separation pilot plant. The pilot plant uses hundreds of stages of solvent extraction (SX) to produce high purity individual HREEs from both primary and secondary resources.This paper presents the design of an HREE recovery process for the particular case of uranium processing wastes. The separation results of a group separation are reported and discussed, as well as the issues and the challenges of the development, commissioning and operation of the continuous SX pilot plant.IntroductionSignificant amounts of strategic specialty heavy rare earth elements (HREEs) are found in uranium wastes in Saskatchewan. It estimated that about 47 tonne/a of heavy rare earth element oxides (HREO) including 27 tonne/a of Y2O3, plus 6 tonne/a of Sc2O3 are in the raffinate of every uranium mill for potential recovery. Since the HREEs are already in the raffinate, cost effective HREE production is promising in Saskatchewan.Selective precipitation including nutraulization, oxalate and double-salts precipitation, as well as sulfide precipitation, ion exchange (IX) and SX are commonly used technologies for the recovery and purification of REE solution. REE oxalate precipitation is an effective technology to remove Fe, Al, Ca, Si and other impurities by taking the advantages of the solubility difference between oxalates of REEs and impurities in acidic solution (Xu, 2005)."

Jan 1, 2017

By Ronald Díaz

"Cerro Corona es un yacimiento porfiritico tipo stockwork con diferentes unidades geometalurgicas, las cuales son alteraciones producidas por una extensa familia de fallas geológicas que determinan un tipo especial demineralización. En ese sentido, a medida que la mina se va profundizando, la roca encajonante será menos alterada, así como se obtendrá una mayor dureza del mineral y los problemas asociados con el menor tonelaje de procesamiento. Por ello, el presente texto señala la optimización del procesamiento de minerales de bajo contenido de arcillas y alta dureza, así como la disminución de la malla de voladura, el incremento del factor de carga, Blending adecuado de mineral duro, la disminución del set de la chancadora, la instalación de cañones de aire en los chutes de transferencia, una mayor adición de bolas, los cambios en los diseños de linea, el control de desgaste de hidrociclones, sintonización de la lógica de control y el control supervisor del molino SAG, etc."

Sep 21, 2013

By Takashi Saito

Since early 1970?s skirt suction foundations (skirted foundation / bucket foundation) have been used as support for large fixed substructures or anchors for floating structures in offshore hydrocarbon development projects. In recent years skirt suction foundations are recognized as one of the solutions in foundations applicable to bridge substructures installed in waters, because skirt foundations have a wide variety of functions such as control of settlement during service life, less impact to environments during operation at installation site. This paper introduces general features of skirt suction foundations, and then discusses design practice of them for the application to bridge substructures, with reference to experiments in both laboratory and field.

Jan 1, 2013

By Fred N. Kissell

This handbook describes effective methods for the control of methane gas in mines and tunnels. It assumes the reader is familiar with mining. The first chapter covers facts about methane important to mine safety, such as the explosibility of gas mixtures. The second chapter covers methane sampling, which is crucial because many methane explosions have been attributed to sampling deficiencies. Subsequent chapters describe methane control methods for different kinds of mines and mining equipment, primarily for U.S. coal mines. These coal mine chapters include continuous miners and longwalls, including bleeders. Coal seam degasification is covered extensively. Other coal mine chapters deal with methane emission forecasting and predicting the excess gas from troublesome geologic features like faults. Additional coal chapters contain methane controls for shaft sinking and shaft filling, for surface highwall mines, and for coal storage silos. Major coal mine explosion disasters have always involved the combustion of coal dust, originally triggered by methane. Thus, a chapter is included on making coal dust inert so it cannot explode. Methane is surprisingly common in metal and nonmetal mines around the world, as well as in many tunnels as they are excavated. Accordingly, a chapter is included on metal and nonmetal mines and another on tunnels. Proper ventilation plays the major role in keeping mines free of hazardous methane accumulations. The ventilation discussed in this handbook, except for the chapter on bleeder systems, deals only with so-called face ventilation, i.e., ventilation of the immediate working face area, not ventilation of the mine as a whole. The omission of whole-mine ventilation was necessary to keep this handbook to a reasonable size and because a huge amount of excellent information is available on the subject.2

Jan 1, 2006

By W. Valderrama, D. G. Almond

Operation of large SAG mills requires a change in the conceptual approach to grinding processes. The traditional energy consumption criteria are now enhanced with new criteria derived from the mechanical dynamics of the mill load. This new approach demands instrumentation capable of providing accurate information about the load movement and the ratio of balls and ore inside the mill. This paper discusses two new performance enhancing tools available to meet these needs.

Jan 1, 2004

By William D. Spielvogel

The Massachusetts Highway Department awarded the Porter Street Outfall Project to the J.M. Cashman Company in November 1991. Timely completion of the Project in one and one half years is critical to the start of the subsequent Third Harbor Tunnel North Approach project. Existing subsurface conditions and the Project's location at Boston's Logan International Airport significantly increases the difficulty of construction. The major contractual work involves relocating a reinforced concrete double box culvert supported on a continuous wood pile foundation. This existing culvert crosses and interferes with the future Third Harbor Tunnel North Approach alignment. Two parallel culverts constructed approximately 20 feet from either side of the future Third Harbor Tunnel alignment replace the existing double box culvert structure. Under the original contract design, approximately 3,100 feet of 14 ft. by 15 ft. reinforced concrete culvert is cast in place adjacent to the west side of the Third Harbor Tunnel and is located in the center of the Airport's main service roadway, Harborside Drive. This culvert is the Porter Street Combined Sewer, PSCS, which handles a combined flow of sewerage from the East Boston community and storm water runoff from Logan Airport. In addition, approximately 2,230 feet of 17 ft. by 15 ft. reinforced concrete culvert is cast in place adjacent to the east side of the Third Harbor Tunnel and is within 20 feet of an active aircraft taxiway and heliport. This culvert is the Bird Island Flats Storm Drain, BIFSD, which handles storm water runoff from the Logan Airport airfield. The existing outfall, on the west side of the Third Harbor Tunnel alignment is to remain in service and is to be connected to the new PSCS and BIFSD culverts. Therefore, a portion of the BIFSD culvert is designed as a bridge to span 128 ft. across the Third Harbor Tunnel excavation during construction.

Jan 1, 1994

By Robert W. Van Dolah

On December 27, 1961, a fire and explosion destroyed the blasting agent mixing plant and an attached storage barn of the Whitaker-Atlas Supply Co., near Norton, Wise County, Va. Five residences, an office building, four trucks, and three automobiles were completely destroyed; a house trailer and several other trucks and automobiles were severely damaged; and other property damage, including much window breakage, occurred up to 3 miles or more airline distance away. Through the quick action of the fire marshal of the Norton Fire Department, Norton, Va., there were no fatalities and only five persons required hospitalization. This incident is of particular interest because of the widespread practice of mixing fuel oil (FO) with ammonium nitrate (AN) to prepare low-cost blasting agents, in many cases under conditions and circumstances not very different from those presented here. A representative of the Bureau of Mines Explosives Research Laboratory, Pittsburgh, Pa., and field representatives of the Bureau's Health and Safety Activities conducted the investigation. Information in this report was obtained from representatives of the Whitaker-Atlas Supply Co., the Norton fire marshal, and others who were on the scene either shortly before or after the incident occurred. Representatives of the Manufacturing Chemists' Association, the Institute of Makers of Explosives, and individual ammonium nitrate producers participated in the inquiries and investigations.

Jan 1, 1962

By A. Wahab Khair, John G. Oldsen, John C. Stankus, Song Guo

During the last several years, implementation of trusses, in lieu of wood cribs, has been successful for supplemental tailgate support in the Pittsburgh seam. This paper reviews, the truss support system provided by the new high strength 0.6" tensioned cable truss, which is now also being used in cribless tailgates. Cable loading and roof deformation were monitored to evaluate roof and floor performance. The test results indicate that the cable truss system successfully controlled the roof and floor during the first and second panel extraction. This paper will describe the advantages of cable trusses and their load transfer mechanism as well as mine evaluation.

Feb 24, 1997

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 instructions 5/ 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 and, 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, 1962

By Douglas W. Fuerstenau

A detailed experimental study of breakage kinetics in a batch rod mill indicates that while the system is inherently nonlinear, the feed disappearance kinetics for the finer sizes and the coarser sizes at high holdups is well represented by first-order behavior. The set of breakage distribution functions was found to be normalizable and independent of particle holdup in the mill. The size discretized initial breakage rate functions were found to be inversely proportional to particle holdup and almost directly proportional to particle size. A linearized grinding model that results from the first-order Taylor's series expansion of the breakage rate expression was found to give good simulations of the mill product size distributions without recourse to any parameter improvement routines. Material transport through rod mills was evaluated by investigating the effect of operating variables on the holdup and residence time distribution of particulate solids flowing through the mill. Identical experiments performed in a continuous ball mill helped delineate the fundamental differences in particulate transport through these two types of mills. Mechanistic interpretations of the observed transport phenomena are presented, and their implications in the context of tumbling mill analysis and design pointed out.

Jan 1, 1980

By A. O. Sfriso

"Numerical modelling is becoming universal in rock engineering practice. Most applications focus on the prediction of failure loads of 2D problems, where the numerical models are useful extensions to analytical methods and experience-based design criteria. For 3D problems and problems where the assessment of serviceability indicators – displacements, ground-structure response, etc. – are of importance, the selection of the constitutive models themselves and the implications of the selection of material parameters may have a very heavy impact on the reliability of the model outcome and its predictive capability.This paper overviews basic common aspects of constitutive equations used in practical rock engineering and summarizes some challenges that are frequently observed when reviewing numerical models performed for routine problems in rock engineering. INTRODUCTIONNumerical methodsFrom a philosophical perspective models, either analytical or numerical, are idealizations of a perceived reality. For us engineers, models are just tools we use to guide our judgement and understanding of the problem in hand. When dealing with problems in rock engineering, we resort to a wide range of techniques:1. Closed form solutions like confinement-convergence methods for circular tunnels: these methods satisfy equilibrium and compatibility requirements at the cost of a crude simplification of the material behavior and geometry;2. Limit analysis methods, like bearing capacity formulas: lower bound methods satisfy equilibrium but sacrifice compatibility, and upper bound methods do the opposite. Material behavior must be simple, geometry admits limited freedom;3. Limit equilibrium methods, like method of slices for slope stability: they satisfy restricted forms of equilibrium, do not satisfy compatibility requirements, require simple material behavior but have a much greater flexibility on geometry;4. Numerical methods, where a mesh is employed to discretize the problem geometry: when properly formulated, these methods satisfy equilibrium and compatibility requirements and give reasonable approximations to the behavior of very complex geometries and construction sequences. Very little restrictions remain on geometry and material behavior, but the cost of calibrating the material parameters can be very high."

Jan 1, 2015

By P Moswate, D Phillpotts, S M. Mantsho, P Strobos

A challenge on many industrial flotation circuits is controlling concentrate mineral grades using measurements that are provided infrequently. The mineral grades in concentrate streams are a critical performance indicator in any industrial flotation circuit. Failure to achieve concentrate mineral grade targets has significant financial consequences on a flotation operation. A violation of gangue mineral grade limits by the concentrator may also result in significant penalties.Online grade analysers which can provide reliable real time grade measurements are essential for effective grade optimisation. The Blue Cube MQi analyser (by Blue Cube Systems) has recently come to prominence for its ability to rapidly determine mineral concentrate grades online and has the benefit of operating in-stream. This has provided excellent insight into the actual process dynamics in the flotation circuit, and hence enabled real-time control and optimisation of concentrate mineral grades.MintekÆs Measurement and Control division, specialising in advanced control solutions for mineral and metallurgical industries, has had the opportunity to link the FloatStar Grade-Recovery Optimiser to the measurements provided by the Blue Cube system at the BCL nickel concentrator plant in Botswana. The project focused on stabilising the final concentrate grade while ensuring the final tailings are minimised, resulting in an improved nickel recovery. This site already had the FloatStar Grade-Recovery Optimiser for several years, but the original grade measurement device was unreliable and ultimately failed. The system was reactivated once the Blue Cube system was installed, replacing the old analyser. The positive results show the advantages of combining reliable real time measurements with an advanced process control system.CITATION:Mantsho, S M, Moswate, P, Strobos, P and Phillpotts, D, 2013. The implementation of floatstar grade-recovery optimisation control solutions using Blue Cube Online grade analysers on industrial flotation circuits, in Proceedings MetPlant 2013 , pp 575-582 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

By G. D. Bakulev

Economic Importance of Gasification of Fuel and Brief Outline of Development of Underground Gasification of Coal in the U.S.S.R. The underground gasification of fuel offers a number of economic and social advantages, principally the following: 1. Full automation of labor-consuming coal-mining processes, which resist complex mechanization and automation, particularly shaft mining. 2. Elimination of hard, dangerous, and often unhealthful mining work. 3. Creation of hygienic conditions for personnel employed in gas production, as well as for those in boiler rooms using the gas. 4. Possibility of automation of complex production processes of thermal-electric powerplants using underground gas with economic installations for steam production. 5. Economic operation of thermal-electric powerplants constructed in the areas of underground-gas production. 6. Release of railroads from the burden of transporting fuel. 7. Extension of the power base of some areas in need of fuel and of the economy as a whole due to use of fuel deposits not amenable to normal mining practices. 8. Reduction of capital investments per unit of energy produced in the form of fuel. 9. Substantial increase in general labor productivity. 10. Possibility of substantial reduction in the cost of fuel produced and of electric power produced from underground gas.

Jan 1, 1962

By J. A. Mielczarski

Surface properties of minerals could be modified selectively and very specifically by adsorption -desorption (dissolution) processes. This requires a monitoring and control of the outermost surface layer at a molecular and atomic level. The nature and structure of self-assembled submonolayers and monolayers at the interface of minerals were studied by infrared reflection spectroscopy. The external reflection spectra of the adsorbed monolayers on any type of minerals: transparent, opaque or non-transparent, recorded at different angles of incidence and for two polarizations are an excellent source of information about the nature and surface distribution of the adsorbed species. The developed method allows to obtain detailed information at a molecular level about the adsorbed surface species. By combination of the simulated and experimental data, the qualitative description of the adsorbed species as well as quantitative evaluation of orientation and the thickness of the adsorption layers were obtained. This fundamental knowledge allows to determine the mechanisms of surface phenomena which govern selective separations. Examples of different surfactant - mineral systems and industrial applications will be discussed.

Jan 1, 2000