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By William C. Cooley

This volume contains copies of the 5 x 8 in. accession card file for all items collected which were judged to be relevant to underground hydraulic coal mining. In many cases, abstracts are included. Abstracts were taken from the source, from other reviews, or from the preliminary screening of Russian documents performed by Dr. A. L. Brichant. No attempt was made to write abstracts for every accession item.

Jan 1, 1975

By H. C. Voges

The concentration of cassiterite at Iscor's Uis Mine is described, and information is given on aspects of the concentration of iron ore at Thabazimbi and Sishen Mines. At Uis, a very Iow-grade tin ore is concentrated by three-stage jigging, spiral concentration, and tabling to give a high-grade concentrate with a recovery of 80 per cent of the tin. A Iow-grade tantalite-columbite concentrate is also produced. The possibility of recovering mica, the use of sluice boxes instead of spirals, and the recovery of cassiterite from minus 45 µm material are being investigated. At the two iron-ore mines, heavy-medium separation is applied to size fractions larger than 0,5 mm. The types of ferrosilicon and the circuits used for the recovery of ferrosilicon from the various dilute-medium circuits are described. The spiral-concentration plant being installed at Thabazimbi for the treatment of the minus 0,5 mm portion of the ore is described.

Jan 1, 1982

By M. J. Pool, P. J. Spencer, R. V. Miner

The partial molar heat of solution of rhodiunz in liquid lin and Rh-Sn alloys has been measured as a function of rhodium concentration at 700" , 725" , 750" , and 775°K. The values at infinite dilution are very exo thermic, ranging from -29,950 to -28,260 cal per g-atom Rh at 700" and 775"K, respectively. At the solubility limit the heat of solution becomes sharply nzore exothermic and has permitted the liquidus boundary to be accurately established at each temperature. From the measurements in the two-phase region of liquid Plus RhSn, the heat of formation of RhSn,has been determined. A large increase in the heat of formation between 725" and 750°K suggests the possibility of a phase transformation in this compound. V ERY few measurements have been made of the heats of solution of transition metals in liquid tin; yet those values that are available are of great interest because of their very large exothermic nature. For example, the heat of solution at infinite dilution of palladium in tin has been measured as about -26,000 cal per g-atom (625" to 800°~),' while the heat of solution at infinite dilution of platinum is even more exothermic at -28,591 cal per g-atom (914°K).' These values are of the same order of magnitude as the heat of formation of many intermetallic compounds and as such clearly indicate that very strong bonding must exist between the solute and tin atoms in the liquid solutions. Rhodium might be expected to display similar solution characteristics in tin in view of its close electronic resemblance to palladium and platinum. Since no thermodynamic data are available for Rh-Sn alloys, rhodium was chosen as an appropriate solute for further investigation of transition-metal systems with highly exothermic heats of solution at infinite dilution. EXPERIMENTAL The heat of solution of rhodium in dilute Rh-Sn liquid solutions was measured as a functlon of rhodium concentration at 700°, 725", 750°, and 775°K. The liquid-metal solution calorimeter used in this work has been fully described elsewhere. At the start of each series of measurements, the solvent bath consisted of about 0.5 g-atoms of 99.9+ pct pure tin. To this was made a number of small rhodium additions, about 0.0005 g-atoms each, and the heat of solution was measured for each. Rhodium of 99.9+ pct purity in powder form was used in order to promote rapid dissolution in the liquid tin. The powder specimens were contained in tin foil stated to be purified (lead-free). This foil was found to have no measurable heat of solution in pure tin so the effect of any impurities could be neglected. The energy equivalent of the calorimeter was experi- mentally determined by dropping tungsten and/or tin specimens at intervals during each series of rhodium drops. The tungsten and tin used were 99.95 and 99.999+ pct pure, respectively. The only heat effect due to a tungsten drop, or a tin drop at low rhodium concentrations in the bath, is the sensible heat of the specimen. The heat content of these materials is well-established and is presented in the compilation of Hultgren et al. 4 As the rhodium concentration in the tin bath increases a small heat effect arises from the reaction: Sn (liquid, T) — & (soln, T) where T is the temperature of the tin bath. Where necessary, this heat of solution of tin was determined by Gibbs-Duhem integration, and corrections were made to the heat effect of the tin calibration specimens and the tin foil containing the rhodium specimens. RESULTS AND DISCUSSION The calculated values of the heat of solution of rhodium in dilute Rh-Sn alloys as a function of composition are shown graphically in Fig. 1. The values have been corrected for the sensible heat of the specimens, initially at 273"K, and apply to the reaction:

Jan 1, 1969

By Kyle Kershaw

Micropiles are routinely used in the United States for foundation support and stabilization of slopes. In recent years, several retaining walls have been constructed using micropiles in an A-frame type configuration to support temporary and permanent excavations at sites with limited access and limited right-of-way. Typical A-frame micropile walls consist of a row of vertical micropiles at the face of the wall and a row of battered micropiles extending into the soil or rock to be retained. The two rows are then tied together with a pile cap such that the front pile acts primarily in bending and the back pile acts primarily in tension. Because of tight right-of-way constraints at a residential site in Aspen, Colorado, it was not possible to construct the wall using conventional shoring systems or micropiles in the typical A-frame configuration. Rather, the wall was designed such that the row of battered piles was installed at the wall face and the row of vertical piles was installed adjacent to the property line behind the wall. As a result of the reverse configuration of the A-frame wall, FLAC, a two-dimensional, finite difference software program, was used to model the soil-structure interaction. The final wall design consisted of both temporary and permanent retaining wall sections with maximum heights of 26 feet. Inclinometers were installed in several piles to monitor the behavior of the retaining walls during and after excavation. This paper presents an overview of the design method, a discussion of construction techniques, and a comparison between the FLAC model and the measured behavior of the wall in the field.

Jan 1, 2007

By A. Ennen, R. Wagner, B. Orberger, J. -M. Milazzo, N. Uhlmann, J. Banchet, J. Lucic, N. Wörlein, M. Firsching, J. L. Dubos, C. Bauer

The residues from mining and processing ores can often be considered as secondary raw materials. However, the material is only available in the form of fine particles (< 3 mm). In order to recycle these wastes, it is necessary to agglomerate it for transportation prior to reprocessing. The resulting agglomerates need to mechanically resist the stress of transportation and loading into the furnace. X-ray computed tomography (CT) is an established method for characterisation of internal structures in material science. This non-destructive technique can provide information on size and distribution of particles and grains. However, the information is not limited to the size, but also can yield structural features like orientation and position of cracks and fractures, which are important features indicating potential for deteriorating the agglomerates. Furthermore, deduced features such as contact conditions of inclusions or boundary surfaces can also be calculated. We studied binder-free tablets of manganese-oxyhydroxide, bentonite, kaolinite and slag powder using micro-CT. Inclusions of highly absorbing particles were identified using a watershed transformation with automatic segmentation by Otsu thresholding. Subsequently, the resulting data was analysed regarding their volume percentage, distribution in size and location within the sample. For the slag agglomerates, the volume fraction of iron could be determined. Furthermore, visible cracks were investigated with the goal to determine the long-term durability. It was shown that the data provided by micro-CT is reliable and helpful for the characterisation of industrial waste agglomerates. Keywords: X-ray, computed tomography, micro-CT, agglomerates, manganese fines, slags, kaolinite, bentonite

Jan 1, 2020

By M. Grenon

"The presence, size, orientation, nature, and persistence of geological discontinuities dictate the behaviour of a rock mass. Block size, which is defined by discontinuity spacing, by the number of joint sets, and by the persistence of the discontinuities delineating potential blocks is an important indicator of the degree of fracturing of a rock mass. Consequently, block size is represented either explicitly or implicitly in all rock mass classification systems employed for analysis and design of surface and underground mining structures. Insitu block size distributions may provide a better means to describe the structural complexity of a rock mass. These are the distributions that would be derived if the in-situ rock mass was separated into its constitutive blocks, delineated by existing discontinuities, and each block measured. This paper presents the results of a field campaign at Louvicourt Mine aiming to characterize the rock mass using different methods for determining block size and block size distributions. IntroductionGeological structural data are used to provide input data for analysis and design methods for surface and underground structures. As the collection of structural data involves considerable investment of time and effort, it is sometimes overlooked, thus denying an important source of information for mine design. What is somewhat surprising, however, is that when structural data are available, they are not used to their full potential. Recent work has shown that data on block size have potential applications in different areas of rock engineering:• Blasting — Hudson (1993) has described the excavation process as the change of a preexisting natural block size distribution to the debris fragment size distribution (Fig. 1). Lizotte and Scoble (1994) have reviewed previous efforts on integrating site specific geological conditions into blast design. Grenon et al. (1997) provide a case study where in-situ block size distributions are compared to photogrammetric studies of blasted rock.• Rock mass classifications — Block size is used in the majority of rock mass classification systems either explicitly, as in the RMi classification system Palmstrøm (1995), or implicitly, such as in the NGI system, Barton et al. (1974)."

Jan 1, 1998

By William H. Pomroy

Spontaneous combustion fires involving high-sulfide-content ores are a relatively infrequent yet serious safety hazard in mining. They are also the cause of lengthy mine shutdowns because they typically occur in areas of a mine where abundant fuel material is present but which are inaccessible for fire fighting. This Bureau of Mines report describes research to design, fabricate, and test in the laboratory and field a system that warns of spontaneous combustion fires in metal mines. Overall performance of the detection system was found to be satisfactory, in that the system was capable of reliably detecting low levels of combustion products believed to indicate the preflaming stage of spontaneous combustion in metal mines. Installation of similar systems in mines with a high risk of spontaneous combustion is recommended. Principal operating problems and recommended corrective actions are also discussed.

Jan 1, 1987

By L. L. Sirois

Because segments of the Canadian mineral-based economy are dependent totally or in part on foreign sources of certain minerals, their well-being may well be affected by inability to obtain these minerals. Where such dependency exists, it is therefore important that contingency plans be available to counteract possible price increases or lack of supplies by means of technology, developed well in advance of any pending crisis . Canada is vulnerable to possible future real or artificial shortages of certain foreign-produced mineral commodities, and science and technology can provide information for the development of policies for counteracting efforts by foreign exporters to control prices or limit supplies.

Jan 1, 1977

By X Zhang, Y Zhu, P E. Ngoepe, P P. Mkhonto, W Xiong, L Han, L Lu

The triazine molecules have not been given much attention and they are potential collectors that may positively impact the mineral processing industry. The adsorption of triazine as collectors such as sodium 2,6-dithio-4-butylamino-1,3,5-triazine (SDTBAT) on pyrite form a basis in design of flotation collectors that may be applicable in a wide range of sulfide minerals. The SDTBAT collector was compared with the sodium normal butyl xanthate (SNBX) and sodium normal butyl dithiocarbamate (SNBDTC). All collectors were adsorbed in their neutral form containing sodium on the pyrite (100) surface. The computational calculations found that the adsorption energies followed the order: SDTBAT (-300.35 kJ/mol) > SNBX (-186.10 kJ/mol) > SNBDTC (-163.78 kJ/mol). It was observed that the SNBX and SNBDTC adsorbed through the S atoms, while the SDTBAT adsorbed through the S atoms and N atoms onto Fe atoms. It is clear that the SDTBAT had a strong binding energy which is attributed to the presence of the triazine group that is electron depositing to the active S atoms compared to the SNBX which possessed the oxygen that is electron withdrawing. Moreover, the SDTBAT collector was found to bind stronger than the xanthate. This was complimented by microflotation tests that showed fast floating and higher recoveries of pyrite when using the SDTBAT collector than the xanthate and DTC. This clearly demonstrated that the SDTBAT is a potential collector to replace the xanthate collector due to its high selectivity and flotation power.

Aug 24, 2022

By G. G. Oberfell

THOUGH the largest volume use of natural gas has been, is. and in all probability will continue to be as a fuel for domestic and industrial heating, it has various market outlets, both as a fuel and as a raw material for the chemical industry. Natural gas is a preferred type of fuel where ease of control, fuel uniformity, and freedom from ash are of primary importance. Other industrially important uses are as a source of carbon black and as a fuel in various low-cost heating operations. Many other uses are of varying importance and new potential uses are continually being uncovered, some being of economic importance to the gas indus¬try as a whole, but most of them involve such small volumes of gas that they are only of passing interest. Since various products extracted from natural gas and recovered as by-products from petroleum refining, such as liquefied petroleum gas and fuel oil, are being utilized in many industrial and domestic heating applications, some consideration will have to be given such materials in order to present a reasonably complete story of the importance of natural gas. Some of these materials may prove to be transient competitors and will not be available when more profitable uses are found for them. Meanwhile, however, the potential volumes of such materials available, the current volumes being marketed, and the nature of the utilization are considered as constituting an essential part of the over-all fuel picture.

Jan 1, 1946

By Elmer A. Peña M

Dado que la concentración de sulfuros de fierro: pirita y pirrotita aplicados gravimétricamente en espirales Humphreys obtuvo resultados óptimos tanto en lo económico como en lo metalúrgico, surge la necesidad de construir una planta concentradora de sulfuros de hierro en la Cerro de Pasco Corporation utilizando como cabeza los relaves de la planta de flotación de minerales de cobre. En este sentido, el objetivo del texto describe el proceso de dicha concentración, donde señala que la alimentación a la nueva planta es una pulpa que requiere mantenimiento de supervisión y mantenimiento, generando un concentrado de fierro a un costo de s/.6. 00 T. C. S. contra s/. 105. 00 T. C. S.; costo del concentrado de fierro producido por flotación en 1961. Asimismo, las diferencias de gravedad específica entre sulfuros de fierro y ganga cuarcífera han ido aprovechados para lograr un ejemplo donde la concentración gravimétrica, actúa con éxito frente al actualmente difundido proceso de concentración por flotación.

Aug 20, 1963

By Paul B. Crawford, Gerald N. Pitts

"A new method is introduced for the simulation by computer of the flow of liquid underground. The method has application in simulating, for example, liquid withdrawal systems, injection systems or injection-well systems. The computer simulation of liquid flow permits the utilization of the known properties of the rock in developing a model of the permeable rock mass.The flow properties of the rock at a specific site arc generated statistically using a random number generator. After defining in this manner the rock properties of each element in the computer grid, the streamlines or flow paths of the liquid are traced using the new method. The simulation is designed especially for computers. The meandering character of the liquids paths is displayed clearly as the fluid moves underground, thus providing the technical information required for the control of the movement of liquid."

Jan 1, 2014

By C. A. Lavery

A DISCUSSION is presented of natural gas production and field processing equipment as now utilized in the gas producing areas of the United States, with reference to use of such equipment in Canadian gas areas. The scope of the paper is confined to a general description of various types and methods of using surface production equipment. The discussion is divided under two general groups: well-head production equipment, and field processing. The first will be concerned primarily with indirect heaters, separators, knockouts, and special versions of this equipment. The second major group includes the field processing equipment for handling natural gas. A delineation should be made here as to the meaning of field processing as used in this discussion. We will limit our term to mean such processing equipment as may be used in producing fields to process gas or its by products in a manner that does not require conventional plant practices either in operation or supervision. This covers such equipment as is necessary to complete preparation of gas for sale to pipeline and/ or is necessary to recover valuable components. Under this heading we will discuss glycol dehydration, solid desiccant dehydration, low-temperature separation, mechanical refrigeration, and desorbtion-stabilization. These are all processes involved in preparing gas for final sale or disposal. They do not include the more conventional and large-scale plant process systems.

Jan 1, 1956

By K. Dagdelen

The definition and shortcomings of traditional cutoff grades are discussed. The concept of optimum cutoff grade policy which maximizes the Net Present Value (NPV) of annual cash flows coming from a mining project is introduced within the basic framework outlined by K. F. Lane. Several examples are used to demonstrate the shortfalls of cutoff grade policies obtained by various heuristic optimization techniques. An algorithm to obtain an optimum cutoff grade policy which maximizes the NPV of a project is given and described in detail.

Jan 1, 1993

By C Claassen, R Balusu

Computational fluid dynamics (CFD) models have been developed based upon field data collected from a longwall mine in New South Wales, Australia to study the behaviour of goaf gas flow in both active and sealed goaf areas. A base CFD model was built to represent the goaf situations when the active longwall retreats near the finish-off line. Results from the base model were calibrated and compared against field goaf gas monitoring data. The base model was then used to carry out parametric studies to investigate a number of operational scenarios and their impact on goaf gas behaviour. CFD modelling results indicate that the overall goaf gas flow pattern changes as the operating longwall retreats towards finish-off line. In all cases, oxygen penetration into the active goaf remains high, reaching 15 per cent or higher, even at some 800 m behind the longwall face.The modelling results also indicated that it would be difficult for early detection of an active goaf heating (on the maingate side) based upon CO readings in the return airflow, as the main stream of the gaseous product will be flowing into the sealed deep goafs in adjacent longwall (LW) panels. Monitoring points (such as tube bundles and bag sampling points) should be selected at deep seated seals along the active goaf so that abnormal CO or C2H6 readings can be picked up for early detection and location of potential heating spots; goaf inertisation can be better achieved by injecting inert gas such as nitrogen at deeper points (&gt;200 m) behind the operating longwall; the injection of in-seam drainage methane into the goaf areas will only have a limited impact on goaf inertisation as much of the injected methane will migrate towards deep and higher parts of the goaf due to its buoyancy effect.

Sep 26, 2011

By Roger Lacroix

L?arrivée de nouvelles technologies sur le marché des foreuses portables combinée au besoin des mines à mieux consommer l?énergie électrique ont permis d?identifier le potentiel de deux nouveaux type de foreuses présentement utilisées en Afrique du Sud, à savoir les foreuses électriques et les foreuses hydrauliques actionnées à l?eau. Grâce à la collaboration de mines Niobec et Géant Dormant de Cambior Inc., ainsi que d?Hydro-Québec, le potentiel réel d?économie énergétique des foreuses portables hydrauliques et électriques par rapport aux foreuses conventionnelles à air comprimé a été évalué pour des roches dures et moles. Ainsi, cet article a pour objectif d faire ressortir ces potentiels d?économie énergétiques. En outre, les résultats pour une mine mécanisée et une autre mine de type filonien, dans lesquelles on retrouve des conditions de terrain différentes, seront présentés. Les résultats montrent un potentiel d?économie énergétique d?environ 70% pour la foreuse électrique et d?environ 50% pour la foreuse actionnée à l?eau. Ces résultats montrent qu?il est possible d?obtenir une meilleure efficacité énergétique par mètre foré. Ainsi, il apparaît maintenant intéressant de poursuivre les travaux de développement des deux technologies pour les applications de forage vertical et de tensionnement des boulons, et de viser à accroitre le taux de pénétration de la foreuse électrique pour le rendre équivalent à celui de la foreuse à air comprimé.

May 1, 2007

By Robert P. Stevens

It is important for a refractory supplier to make systematic petro-graphic examinations of products which have been in service in the furnaces and kilns of customers. The petrographic examination of refractory service samples involves the microscopic study of polished and/or thin sections, supplemented by electron probe microanalysis, as well as the bulk chemical and XRD analysis of zones in the samples. The evolution of the A. P. Green Refractories Company petrographic laboratory is described, and the application of petrographic methods is illustrated in the examination of service refractories from a Portland cement rotary kiln and an AOD stainless steel vessel. The objectives of such studies are to assist the customer in the solution of his refractory problems, and to accumulate data which are of use in the design of improved refractory products.

Jan 1, 1981

By Peter R. Drummond

THE paper consists of four sections: (1) a discussion of early work; (2) presentation of the results of a chemical investigation of Falcon-bridge nickel-copper blast-furnace matte; (3) application of the results of this investigation to mattes in general; and ( 4) a summary of conclusions. All general discussion will be confined to the fundamental system of ferrous-cuprous sulphides (FeS-Cu2S). Nickel-, lead-, and zinc-bearing mattes will be treated as minor varieties of the parent system. DISCUSSION OF EARLY INVESTIGATIONS Matte investigations may be divided into three classes: first, those treating the sulphides as alloys-theoretical studies of the system FeS-Cu2S, such as those of Hofman (ll)t or Carpenter and Hayward (2); second, chemical research on mattes made under smelter conditions, such as that carried out by Hawley (3) or Avetision ( 4); third, combinations of the . above, such as the investigations of Gibb and Philp (5) or Fulton and Goodner (6). Much research in the first of these classes, including determinations of . freezing points and of data for structure-composition diagrams of the system FeS-Cu2S, was carried out in the period 1890-1910. LeChatelier and Ziegler (1, 13) proved that FeS, when heated alone above its melting point, dissociated in part, and Friedrich ( quoted by Fulton, 6) showed the same for Cu2S. The reactions may be expressed by the following equations: [xFeS yFe + yS (volatilized)+ (x -y)FeS xCu2S )&apos;Cu+ yS ( vohtilized) + (x -)&apos;)Cu,S ] Sulphur is lost by volatilization, leaving a melt of metallic iron plus ferrous sulphide in the one case, and of metallic copper plus cuprous sulphide in the other. If the mixed sulphides are heated far above their melting points, there results either an iron-rich matte containing Fe-FeS-Cu2S or a copper-rich matte containing FeS-Cu2S3-Cu, depending on the relative amounts of each sulphide in the mixture.

Jan 1, 1940

By Jim Pae Lem

This study investigates the mode of occurrence of uranium in a copper concentrate from the Prominent Hill mine. Mineralogical and liberation studies of a high grade Cu concentrate (monthly composite) containing uranium (U) were undertaken using QEM-Scan in combination with QXRD and ICP-MS. The study aimed at determining in what form U was recovered, and by which mechanisms. The deportment of U was studied in 3 size fractions; +20µm, -20+8µm and -8µm. QEM-Scan analysis showed that uranium was present as U(Cu)-silicates, U-silicates, UPbOx/FeOx or traces of UThOx and UTiOx, with the U-silicates present across the size fractions. The association of uranium bearing minerals with copper sulphides varied across the size ranges. Interestingly, most of the U (46% by weight) was distributed in the finest fraction (-8µm), in which the deportment of Cu was low (6%). Over 40% of the U mineralisation in the -8µm was liberated. In terms of the floatation response, while recovery of the uranium minerals as a result of their association with copper sulphides (as composite particles) was evident, recovery of UPbOx locked in hydrophilic haematite in the +20µm size fraction suggests, that other mechanisms (e.g. Inadvertent activation by Pb from radioactive U decay) are possible. Furthermore, the high amount of fine liberated U bearing particles in the concentrate points at entrainment as another major mechanism for uranium recovery, and therefore, a target for process optimisation.

Sep 1, 2012

By J. L. Fuller

Mine ventilation surveys were conducted by Technical Support engineers during June 1987 and September 1989 at the Dutch Creek Hine. The mine is located near Redstone, Colorado and is operated by Mid-Continent Resources, Inc. Following completion of the initial survey, several recommended improvements were incorporated into the ventilation system by mine personnel. The second survey permitted documentation of the effects of those changes on the ventilation system performance. This paper describes the processes involved in the implementation of the recommended changes. The substantial improvements in system efficiency and reduced operating costs are also described.

Jan 1, 1991