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By F. Barriga-Ordonez, J. A. Finch, L. Calzado, S. R. (Ram) Rao

Sludge, formed by lime treatment of acidic drainage and stored in tailing ponds of the Sudbury region, contains 5-7% Ni, mostly in a mix of hydroxides with Fe (~ 10%), Mg (~ 10%) and Cu (-0.5%), and Ca (-3.5%) as sulphate. Investigations were conducted to recover nickel by a 2-stage process. In the first stage, the sludge was leached with sulphuric acid at pH 3.2. About 90% of the nickel was extracted, producing a solution, which contained mainly nickel (2 g/L) and magnesium (3.7 g/L). In the second stage, nickel was separated by treating with ozone which recovered 99% of the nickel in the Ni(III) oxidation state as -85% pure nickel oxide-hydroxide (NiOOH) precipitate. The oxide settled and filtered readily. A potential use of the product in battery making is suggested. The leach residue contained 0.5% Ni making it less toxic for disposal. Some physical properties of nickel oxy-hydroxide and process parameters including ozone consumption will be discussed.

Jan 1, 2005

By S. Prasad

The effectiveness of ultrasonic velocity measurements and attenuation of the propagating pulse was evaluated as a means of Non-Destructive characterization of cold worked and annealed copper. Commercial copper is subjected to mechanical working such as forging, rolling and thermal treatment to induce re-crystallization. The microstructural changes that occur in copper and a variation in its mechanical properties are subjected to analysis using the ultrasonic technique. The signal processing is carried out using the wavelet analysis technique. The features of wavelet analysis namely, localization in space and the presence of an infinite set of basis functions allows removing noise from the time series and components of a non-stationary signal to be analyzed. This is seen to improve the accuracy of the results obtained from the ultrasonic technique in the case of copper, which has distinct coarse grains that are difficult to inspect due to backscattering from the grain boundaries.

Jan 1, 2010

By Tao Zhang, Wen-tao YU, Hai-bin ZUO, Jian-Liang Zhang

Sintering-pot tests and metallurgical performances of sinter with 4 kind of different Al2O3 contents are experimented in this paper. Results show: when the Al2O3 contents increase from 2.0% to 3.5%, acicular calcium ferrites in mine phase will be gradually replaced by plate-like iron calcium. The increase of Al2O3 contents will lead to the addition of liquid viscosity and the reduction of permeability of sinter bed. Sintering time will be prolonged. The rate of yield is stable basically but production is low; besides, the increase of liquid viscosity will decrease of drum strength. The change of permeability of the material layer will make RDI +3.15 decrease first and then increase when Al2O3 contents changed from 2.0% to 3.5%. RI of sinter shows a contrary trend because many open voids are formed by deterioration of liquidity first and then pores closed.

Jan 1, 2015

By Michael S. Miller

In 1987 and 1988, at the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied the 3,100-acre Borah Peak Wilderness Study Area (10-047-004) and a 708-acre parcel adjacent to the north in order to evaluate their identified mineral resources. The study area is located in Custer County, ID, about 18 mi northwest from MacKay. The study area lies along the western foothills of the Lost River Range and is underlain by quartzite, sandstone, shale, argillite, dolostone, and limestone. The Lost River fault, a major active fault, lies along the length of the study area. Large alluvial fans spread out from valleys originating east of the study area.

Jan 1, 1989

By Steven W. Schmauch

A mineral survey by the U.S. Bureau of Mines and U.S. Geological Survey indicate the Blanco Mountain RARE II area has low potential. Lode deposits consist of small, mineralized quartz or quartz-gossan veins. The veins are sparse and widely separated and lead, silver and gold content is restricted in amount and concentration. No gold or other potentially economic minerals were found in a placer deposit. There is no evidence of industrial mineral, geothermal, or energy resource potential in the study area. INTRODUCTION A mineral resource survey of the Blanco Mountain RARE II area (No. 5059), Inyo and Mono Counties, California was conducted in July 1981. This report summarizes the results and interpretations of the Bureau of Mines investigation.

Jan 1, 1982

By E. O. Afreh, R. J. Bowell, E. Hanssen, D. Pohl, S. Abe, R. K. Yao, N. d'A. Laffoley

In the largely preserved laterite profiles at Syama mine, in the savanna region of southern Mali, element geochemistry in the mottled-clay horizon and below can be related directly back to the protolith, but above this, in the ferricrete and cuirasse horizons, the hypogene signature is much modified by pedogenic processes. In tropical rainforest terrains extensive remobilisation can result in wide but weak geochemical targets for gold and pathfinder elements. At the Hire concession in central Ivory Coast, intense recent alteration of the largely intact laterite sequences has modified soil-geochemical dispersion patterns extensively, producing Fe-rich nodular stone lines and obliterating previous patterns and features. Where the upper horizons of the laterite profile have been removed or reworked, as at the Senoufo concession in northern Ivory Coast (savanna) or the Kubi prospect in Ghana (rainforest), all soil horizons can be related directly to hypogene geochemistry. In these truncated profiles, gold and base metal anomalies are essentially those of the lower weathering profile and form narrow but strong dispersion haloes. A good understanding of the geochemical processes active in deeply weathered profiles is required if targets are to be recognised effectively

Apr 1, 1996

By K. Madhusudan Reddy

Pile response under combined uplift and lateral load is very important and it is imperative to evaluate the effect of combined loading and only few studies were reported on pile behavior under combined uplift and lateral loads. Model pile made-up of aluminum having an outer and inner diameter of 25.4 mm and 19.4 mm respectively is used. Dimensions of the model steel tank are fixed as 1.0 m x1.0 m x 1.2 m (depth) to avoid the boundary effects under combined lateral and uplift loads. Experiments were carried out on single piles at isolated uplift, isolated lateral loading and combined lateral and uplift loading, embedded in sandy soil. Results indicate that load?deflection behavior is nonlinear for isolated uplift and lateral load tests as well as in case of combined loadings. It is also observed that the behavior of piles under isolated loadings is substantially different when compared to combined loading.

By Antti Porvali, Vivek Agarwal, Mari Lundström

Hydrometallurgical recovery of rare earth elements (REE) from NiMH battery waste can be performed using sulfuric acid leaching followed by selective precipitation as double salt (REENa(SO4)2·H2O) by adding Na2SO4 as a precipitating agent. The formed double salts can then be further converted with NaOH solution to form REE hydroxides. However, present literature has paid little attention to how to minimize the consumption of reagents in this recovery process. In the current study, a process model was built using HSC Sim software, and metamodeling of the simulated flowsheet was conducted with the design of experiments (DOE), after which the basic functionality of the flowsheet was verified by experimental work, starting from sulfuric acid leaching of spent batteries. As the process is based on chemical circulation internally in the process, the objective was to investigate the accumulation of the elements in solution, specifically Na+ , K+ , SO4 2− ions and impurities liberated in the NaOH conversion step. It was found out that metamodeling could be utilized in obtaining first estimate of the process behavior, prior to any experiments. Flowsheet functionality with circulated solution was confirmed, obtaining at best 96.9% La recovery.

By Carl Belser

This report on tungsten in Ouray, San Juan, and San Miguel Counties, Colo., is one of a series describing results of studies on the tungsten potentialities in Region III, Bureau of Mines. The San Juan tungsten deposits occur in an area of 250 square miles, centering near the common corner of Ouray, San Juan, and San Miguel Counties (fig. 1). Field work supporting these studies was done in May 1954. Bureau of Mines reports prepared from investigations made during World War II and under the Defense Production Act of 1950 were reviewed.

Jan 1, 1956

By Z. Zhiqun, V. A. Marple, B. Y. H. Liu

"IntroductionIt is commonly understood that aerosol particles may be injurious to human health if they are of a size that enables them to enter the respiratory tract. Coal Workers' Pneumoconiosis (CWP) is one disease known to be caused by coal mining related particles.The location in the respiratory tract where the particles are deposited is primarily a function of the equivalent aerodynamic diameter (EAD) of the particle. The equivalent aerodynamic diameter is the diameter of a spherical particle with a density of 1.0 gm/cm3 with the same falling speed as the particle in question. For a spherical particle the calculation is rather simple in that the equivalent aerodynamic diameter is simply the diameter of the particle in question multiplied by the square root of the density of the particle. For irregularly shaped particles, such as coal particles, there is no simple way to make the EAD calculation. For example, Figure 1 is only one of an infinite variety of particle shapes that can be found in practice and the aerodynamic size of this particle and, therefore, its deposition location in the respiratory tract would be nearly impos-sible to estimate accurately.The normal method for determining the aerodynamic diameter of particles has been to experimentally measure the size of the particles in a settling chamber or with an inertial classifier such as an impactor, cyclone or a centrifuge, since inertial classifiers have the property of classifying the particles according to their aerodynamic diameters."") However, these devices can only give limited information on the EAD of a single particle with a specific shape. Impactors and cyclones, for example, collect particles in size ranges and not at a specific size, so the determination of the EAD of a specific particle is not possible. A centrifuge, on the other hand, can measure the EAD of a specific particle but the equipment is costly and procedure laborious, and it may not be possible to disperse a particle of a specific shape into the centrifuge. The centrifuge can be used to determine the EAD of clusters of spheres in various arrays, but introducing particles of a specific irregular shape may not be feasible. Furthermore, the EAD is a function of the orientation of an irregularly shaped particle and the orientation of a particle in an inertial classifier is unknown. The orientation may also vary as the particle passes through the classifier.Because of the difficulty in determining the EAD of an irregularly shaped particle, we have undertaken a program to apply theoretical numerical methods to calculate the EAD of any shape particle. In our laboratory we have, for some time, been using numerical methods to determine the flow field of air within instruments such as impactors, (2) inlets, (3) and virtual impactors (4) Recently, this technique has been expanded into the three-dimensional regime, and the flow fields and particle motion characteristics within cyclones (5) and glove boxes have been studied. We have now begun to use these numerical three-dimensional flow programs to study the flow field around irregularly shaped particles to determine their drag coefficients, falling speed, and thus, their EAD."

Mar 1, 1989

By G. H. K. Schenck

Weather changes of a daily, weekly, or seasonal period affect mineral production and cause significant losses that are considered unavoidable. Private weather forecasting services are available on a contract basis that can significantly reduce the uncertainty associated with weather-induced changes in the production of and demand for minerals. This paper provides examples of current practice and reviews the opportunities that await those producers who incorporate weather services as an integral part of their operating, scheduling, and planning procedures. Private weather forecasts can be highly accurate because atmospheric trends such as conditions and movement tend to persist and are related to previous meteorological events. Commercial meteorological services are prepared to deal specifically with a mineral producer's special problems (Table 1). Tactical use of private forecasts is a major advance over the severely restricted value of public forecasts which, of necessity, are general in nature and cover a dispersed geographic territory. Private weather services provided on a consulting fee basis offer the mineral producer the opportunity for tactical and strategic response to weather conditions at an acceptable cost. This contrasts with the too-frequent current tendency to view weather as a random variable the costs of which are unknown and about which nothing can be done.

Jan 1, 1970

Thermal method of diagnostic as a nondestructive monitoring is based on data logging of infrared radiation from heated surface or from the associated thermal field. Monitoring of gearcases and motors hidden faults, such as, bearing degradation (deep-seated wears and tears, fretting wear, spalling and jamming solids of revolution) is closely related to high variations in temperature. The use of portable thermal imaging devices provides considerable advantages due to: easy remote access to the unit under test even when it is operating; minimum time required to obtain information and an opportunity for a real-time diagnosis of the tested subject's condition.

Dec 6, 2010

By Yi Luo

In dealing with various subsidence cases, accurate predictions of mining induced subsidence are the basis for correct assessment of subsidence influences and subsequent mitigation efforts. There is a good demand for a reliable tool to perform the subsidence predictions and related tasks. A comprehensive and integrated subsidence prediction model, CISPM, developed by the senior authors in the later 1980?s and early 1990?s (Peng and Luo, 1992) is one of such tools. Built on solid mathematical models and calibrated by a large number of collected subsidence cases, CISPM provides a rich set of features needed in subsidence engineering and research works. Its reliability and usefulness have been proven by numerous field applications. This upgrade of CISPM will not only preserve its original features and reliability but also provide some new needed features and a more user-friendly working environment.

Jan 1, 2008

By Jacqueline V. Rich

The relationship between surface and ground water quality and copper mining in the Globe-Miami area is investigated in this three-year study. Methods to prevent, minimize, mitigate, or treat polluted waters are identified and evaluated. Best Management Practices are incorporated in a recommended plan to manage the area's water quality.

Jan 1, 1983

By Renan Oss Giacomelli

The adhesion of multifunctional coatings on soft substrates is of paramount importance in the tribological behavior of this important class of surface treatment. In particular, scratch and indentation tests have been extensively used in order to assess this property. In this paper, the adhesion of a-C:H diamond-like carbon films deposited on nitrided low carbon steel was evaluated by indentation and scratch tests. The coatings were produced by PECVD onto 1020 steel substrates with two different surface finishing: ground (Sq = 0.184 µm) and polished (Sq = 0.002 µm). Indentation tests using a Rockwell diamond indenter were conducted and the adhesion evaluated by measuring the spalling region on images obtained by using optical microscopy. The analysis of the spalling regions produced semi-quantitative results, eliminating the subjective qualitative analysis proposed by the standard method VDI 3198. In addition, scratch tests were performed using the same indenter and a comparison between the two techniques was established.

Jul 31, 2018

By R. V. Ramani

"A computer simulation model of a dragline has beer developed for the study of alternative dragline deployment schemes for varying geological and mining conditions. In this paper, the mathematical aspects of the model, the input data and output results are discussed. An application of the model to a coal mine in eastern Kentucky is presented.IntroductionDraglines are very productive machines. To extend their operating ranges, they are operated in several modes such as advance benching, key cut, extended benching and pullback. Unfortunately, these variations result in low machine productivities. Appropriate methods to operate these machines must be developed on the basis of detailed analyses of dragline performance under varying geological and mining conditions. There are several standard engineering procedures for the selection of dragline, and design of a dragline pit (Ramani, Iroegbu and Manula, 1976). However, the complex interrelationship which exists among equipment, methods and natural conditions can be quantified only through orderly and systematic experiments.Computer simulation is well suited to studying these types of equipment selection and method layout problems. Several alternatives can be analyzed in a relatively short time by the modification of input variables. Also, the application of computer simulation models can significantly reduce the manpower and cost required for such analysis."

Jan 1, 1985

By John G. Palmer

Continued development of an especially impregnated silica gel capable of reversible chemical detection of carbon monoxide (CO) was reported. The affects of changes in mine-related ambient conditions on the detection catalyst's response were explored. Temperature, humidity, and several interfering gases were found to affect the detection catalyst. The interferents include hydrogen sulfide, nitrogen dioxide, acetylene (and methylacetylene), and ammonia. High humidity decreased the detection catalyst's sensitivity to carbon monoxide for some formulations. Increasing temperature generally decreased the reaction time of the detection catalyst with carbon monoxide. Badges and carriers for the visual presentation of the detection catalyst were constructed. Several variations of these devices included provisions for absorbants and filtering agents which help protect the detection catalyst from gaseous interferents. A variety of catalyst support agents were tested in an effort to find the most suitable. Included were alumina, magnesium oxide, magnesium silicate, and several forms of silica gel. In addi tion to free-flowing forms of these sorbents, thin layer chromatography plates coated with cellulose, alumina, and silica gel and newly developed PTFE entrained silica gels were examined. A limited physical, chemical, and mechanistic characterization of the detection catalyst and the materials used to prepare it has been carried out. Metal component ratio studies, spectral, analytical, pH, and rate measurements were done.

Jan 1, 1982

By Kenneth Eilerts

[The development and operation of ?combination on wells?5/ have created new and unusual problems, many of which cast to solved only if information is available concerning the properties of the fluids produced. Data as to the characteristics of the fluids at the relatively high pressures that exist in the reservoirs are especially important, and there is growing economic concern to know what part, if any, of the liquid recovered at the surface was liquid in the reservoir, As an extension of this problem, it is important to Know whether liquid will be formed in the reservoir it as a result o a isothermal retrograde condensation when the reservoir pressure is reduced. The pressure range of such condensation, if it occurs, is significant in the design of gas-recycling plants for maintaining reservoir pressures. In connection with the operation of such plants, it is particularly important to know how gyres sure and temperature will affect the yield of the liquid phase and the composition of the gas to be returned to the reservoir. It has not been possible to predict the behavior of these fluids that have high ratios of gas to liquid by comparing them with the behavior of low gas-liquid ratio fluids at identical pressures and temperatures. Such comparison fails because the proportions in which a component will be distributed between the phases of a system at any given temperature and pressure depend increasingly on the composition of the mixture as the critical temperature and pressure of the oysters are approached. Because many combination wells are producing from reservoirs that have temperatures near the critical point, experimental date on the properties of the fluids under reservoir conditions are particularly important at this time. To rest the immediate requirements of the industry for such experimental information an equilibrium cell has been constructed at the Petroleum Experiment Station of the Bureau of Mines, Bartlesville, Okla. When adequate experimental date, have boon accumulated, it may be possible to mare dependable estimates of the phase relations ft. high gas-liquid ratio fluids at the pre runes and temperatures characteristics of ?combination-well? reservoirs.]

Jan 1, 1940

By H. K. VAN POOLLEEN, W. Hurst, H. C. Bixel

In an earlier publication* I showed the development of the instantaneous point source solution for a well producing at a constant rate at the center of a system of two radial, adjoining sands of different permeabilities. I also showed how a wellbore radius could be incorporated if this were the development required. For the purpose of that paper and the point I wished to make, this solution served. It yielded a simplifying solution of sands in series identified by Eqs. VI-26 and VI-27. (These equations are reproduced in part by Bixel and van Poollen as their Eq. 3, Page 302.) I am well aware that the simplified solutions are approximations. The facts that these Ei-functions satisfy the diffusivity equation and meet the boundary conditions both at the well and at the interface between sands, and that the earliest time considerations yield zero pressure drop, are evidence that the solutions are good approximations. This was the purpose for these formulas, which I interpret that where the permeabilities are of finite order of magnitudes in the respective media, the relations give satisfactory answers. However, from the authors' point of view there are reservations, which leads me to consider their entire generalization as illustrated in their Figs. 1 through 14. What I understand from their storage capacity, relationship Fs, which is the ratio of the product of porosity and compressibility of Sand II to Sand I, that is employed here by the authors as a correlative means of identifying one figure from another, there is nothing in the exact mathematics that supports such a term as a means of correlation. This is taken out of context, unsustained that this applies. Here the mathematics are known, where the true correlation is the diffusivity term of one sand to another. This entails permeability that refers back again to the term M in their paper for the transmis-sibility of fluid from one sand to the other that should have also been a part of this storage capacity. In Figs. 8 through 14, which purported to show the simplified equation following this correlation, there are apparent discontinuities for M equal to or less than 0.1000 that differ from the trends for greater values of M. In this connection there is no reference radius given for this cumulative pressure drop in the paper that would permit me to make these calculations. However, what is clear for M equal to 0.1000 or less we are treated to almost a closed barrier at the interface; a condition entered by the writers without qualification. This across-the-board treatment of these simplified formulas, whatever the motive of the authors, enters into a range of permeabilities that even I as the contributor would have reservations that such could apply. Under comparable conditions I would be looking at a closed reservoir or some facsimile for such. The extent to which the approximation or the exact equations pertain is not evident in the generality offered by Bixel and van Poollen in their paper. Only when they or other writers show the comparison of the pressure distributions within the formations can one be able to judge the rational limits to subscribe to the simplified formulas.

Jan 1, 1969

By E. G. Valdez

Three cryogenic systems that utilized liquid nitrogen, dry ice, and methanol with dry ice were investigated in conjunction with crushing and classifying techniques. The systems were used to aid in separating and reclaiming the metallic components contained in insulated wires, shredded automobile nonferrous metal concentrates, small motors, generators, and rubber tires. Wire strands, 2 to 6 inches long and insulated with polyvinyl chloride and neoprene, were chilled at -60° and -195° C, then roll-crushed and processed by water elutriation; this procedure resulted in two products--a sink fraction that was 99 percent metallic and a float fraction that was 99 percent nonmetallic. Excellent separation of zinc die-casting alloys from copper and aluminum contained in shredded automobile nonferrous metal concentrates was attained by chilling at -72° C for 1 minute, crushing in a grateless hammer mill, and screening. From the screened products, 97.2 and 100 percent of the copper and aluminum, respectively, were recovered in the plus Pinch fraction, and 100 percent of the zinc was recovered in the minus 1-inch fraction of over 97 percent zinc die-cast purity. Laboratory experimental results comparing direct and indirect chilling indicated that a sufficiently low temperature could be attained by indirect chilling to permit use of a liquid C02-dry ice system on insulated wires and mixed nonferrous metallic concentrates.

Jan 1, 1973