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THE Synthetic Liquid Fuels Act (30 U.S.C., 321-325, and amendments) become law April 5, 1644, and a period of intensive research and development in this field was begun by the Bureau of Mines. As part of this program bulletins were published on a pressure hydrogenation,3 the Fischer-Tropsch synthesis,4 and oil shale.5 The Bureau also has published a short bibliography on coal gasification,6 mostly of a theoretical nature. Because coal gasification is prerequisite to Hither the Fischer-Tropsch or coal-hydrogenation processes, publishing this sizable, collection of technical information in this form will be valuable. The material is presented in three parts, as follows: I. United States Patents. II. United Kingdom, Australian, Canadian, and South African Patents. III. Belgium, French, German, Italian, and Swedish Patents. The domestic patents for this bulletin were collected between 1963 and 1955. Some of the Foreign Patents were collected at the same time and a few of them later in 1961. Part I was published in 1960; Part II was published in 1962.

Jan 1, 1964

By D. Newman

Multiple seam mining is prevalent in Southern Appalachia because economically mineable coal seams are numerous and frequently occur in close vertical proximity. West Virginia, Kentucky, and Virginia have 117, 55, and 40 mineable coal seams respectively. It is extremely rare to have an underground mine that has not been undermined, overmined, or has mining adjacent to it. In many cases the multiple seam mining is concurrent with extraction sequenced in superjacent seams. Because underground mining is focused on recovering the most valuable reserves, mining is rarely practiced from the top seam down, which is the practice most conducive to stability. The combination of room-and-pillar mining methods that include development only, small block, partial retreat, full retreat, and longwall mining produce a wide range of mining geometries and complexity in underlying and overlying seams. In the future, the number of multiple seam operations will increase as reserves are depleted and future mines are, by default, located closer to abandoned mine workings. The improved coal market has transformed many formerally uneconomically mineable seams into attractive reserves. The approaches and methodologies used for multiple seam stability analysis are dictated by the site conditions, including overburden/interburden thickness and lithology, mining geometry, and the mining methods in both the active and abandoned mines. Multiple seam stability analysis using analytical and numerical methods is illustrated by two case histories that reflect close proximity room-and-pillar mining and mining in bump prone situations.

Jan 1, 2007

By Zhuo Chen, Jun Zhou, Jiemin Zhou

Samples of the reacting suspension particles were taken from the reaction shaft of a commercial flash furnace at different heights. The processes of matte and slag formation and morphology of the samples in the shaft were observed and analyzed. Variations of matte and slag composition in the shaft were investigated. By analyzing the samples taken from the settler at different locations, settler processes were studied such as slag formation, agglomeration and separation of matte-slag phases, Fe3O4 reduction, copper-in-slag reduction etc. In accordance with the characteristic of matte and slag formation the flash furnace can be divided into 6 functional regions, and a mechanism model called as “Micro bath process” is proposed for matte and slag formation in a commercial flash furnace. INTRODUCTION During flash smelting, concentrate particles scattered in the reaction shaft complete their oxidation reactions in suspension. The droplets produced fall into the settler beneath with a small amount of un-melted solid particles, agglomerate and separate into matte and slag layers which are tapped out from their tap holes separately. With respect to the extent of slagging reaction in the reaction shaft, there isn’t any commonly accepted understanding in literature (Kimura, Ojima, Mori & Ishii, 1986; Kemori & Kondo et al.,1988; Kemori, Denholm & Kurokawa, 1989; Fagerlund &Jalkanen, 2000). Some assume that the slagging reaction in the shaft can be ignored and some propose that all slag is produced in the shaft. With regards to the characteristics of the physical-chemical changes of concentrate particle in the reaction shaft, although there are some research results reported from pilot scale and commercial scale experiments (Kemori, Ojima & Kondo, 1988; Hagni, Vierrether & Sohn, 1988; Jorgensen, Taylor, Dickinson & Stevenson, 1992; Swinbourne, Simak & Yazawa, 2002; Kivinen & Tuominen, 2005), they are generally limited themselves to theoretical analysis and calculations. No studies are published concerned with the processes of matte and slag generation in the shaft, quantitative analysis of the processes, variations of matte and slag composition and morphologies of the melts along the axis of the shaft, etc.

Jan 1, 2019

By Kot F. v. Unrug

The present combination of coal market prices and reserves, situated in the Central Appalachian Coal Field, is such that mining of smaller coal reserve blocks has become economically attractive. In above drainage deposits, and particularly under mountain ridges, overburden depth can be changing within a wide range. Mines operating in these deposits are usually developing mains along the center of the ridge, with panels projecting from the mains towards the outcrop. Due to changing topography, proximity of the outcrop, and related cover depth, the panels have various lengths. In this reported case study, a mine in Pike County, Kentucky, along the Kentucky ?West Virginia border, difficult ground conditions were encountered, during the development of the mains, under shallow cover, along a narrow mountain ridge. An area having unusual density of vertical joints was encountered. Mining operations were suspended because of roof stability concerns. The ground conditions were studied, analyzed, and control measures proposed to ensure safe passage through the difficult roof area of the mine. The advancement of the mains, through this area of challenging ground conditions, was successfully completed. In this paper, ground conditions are described, with an explanation of the geologic process contributing to their formation. It is interesting to note that similar locations were predicted by the authors, to be encountered in the same mine, based upon the experience gathered from studying conditions of the case described within this paper. When approaching the predicted locations, stability problems appeared to be even more challenging than those encountered previously. Due to changes in the coal market, mine management chose to move the affected mining section to another area of the mine having better coal quality. The advancement of the mains, through the difficult ground conditions, was temporarily postponed. Based upon the analysis of a probable kinematical mechanism of blocks in the mine roof, ground control measures were proposed. The actual application of these principles proved to be appropriate, ensuring safe passage through the difficult ground conditions encountered in the mine.

Jan 1, 2006

By Cocquio D. S, Bauchau C

In the course of an integrated airborne survey in 1975, a uranium-molybdenum deposit was discovered by Minatome Australia Pty Limited in North Queensland, Australia, approximately 70 km by road west of Townsville.The mineralization occurs in a welded tuff unit within the Carboniferous St James Vokanics. It is structurally controlled by a complex of subvertical east-west fractures and is exposed over a strike length of 350 m. Drilling has traced a further 150 m extension underneath a barren capping consisting of a thick pile of vokano-sediments. The maximum width of the orebody is 150 m, and its vertical thickness is approximately 100 m.The primary ore minerals are coffinite, pitchblende and molybdenite, accompanied by various alteration products (particularly uranium molybdates).The vein-type mineralization is considered epigenetic.A comprehensive program of surface drilling and underground exploration is in progress to establish the uranium and molybdenum reserves.

Jan 1, 1980

By Jeff Kravitz, John Kovac, Wayne Duerr

Since 198 1, Federal mining law has required every miner working in underground coal mines to have a self-contained, self-rescuer (SCSR) available for use in emergencies. Some miners that have escaped from fires using SCSR's have reported that they had to remove their mouthpiece to talk during escape, thus compromising the protection afforded by the SCSR. If miners are in thick smoke during an escape, they may have trouble if they become separated from their group. The visibility can be so poor that separation can occur at very short distances. To address this problem, two-way, FM radios were built into the SCSR to improve the ability to communicate should the miners be separated over relatively short distances. The SCSR prototypes built and used in testing included both two-way radios and improved mouthpieces. Comparison studies were conducted using combinations of the new and old mouthpieces, and trials using the radio or not using the radio. Subjective judgments indicate that communication ability was significantly improved using the prototype devices. Communication problems have been encountered with teams using standard voice- powered communications systems. Mine rescue teams perform rescue and recovery work under extremely hazardous conditions, life lines are a standard part of mine rescue team equipment. Leaky feeder and quasi-leaky feeder life line communications systems provide significant improvements over standard systems. These improved systems allow all members of the team to communicate with each other and their base of operations. These innovations will significantly enhance the safety of mine rescue operations.

By M L. van Kampen

The Resource Management Act 1991 provides for activities to be classified as permitted, controlled, restricted discretionary, discretionary, non-complying or prohibited in district and regional plans. This paper looks at the use of the prohibited activity status to restrict, in particular, mining. Often the use of prohibited activity status for mining appears to have no basis other than the negative perceptions that the local community and/or the planner drafting the plan has toward mining and quarrying.   The paper will address the current appeal regarding the use of prohibited activity status now before the Court of Appeal, and the history to the litigation. The relevance of the outcome of the appeal to the minerals sector will also be explained.

Jan 1, 2007

By O. C. Blade

Studies on more efficient utilization of petroleum have been made for 50 years by the Bureau of Mines. As part of this work, the Bureau has analyzed thousands of samples of crude oil by its standardized routine method, and many of these analyses have been published, sometimes in special compilations, other times in connection with reports of research on petroleum. This report is a finding index for all analyses published from 1921 to 1959, and brings up to date the information in Information Circular 7470 3 and in the appendix of Bulletin 490.4 The routine method of analysis and the equipment originally were described in a report by Dean and associates. 5 This report has long been out of print, but Bulletin 490, bringing the procedure and its modifications to date, was published in 1951. 6 Briefly, the procedure consists of testing, by standard methods, small samples of a crude oil for gravity, sulfur, color, viscosity, pour point, and (more recently) nitrogen; and, by a standardized procedure, distilling a portion of the crude oil and determining certain properties on the separated fractions and residuum. Careful records are made during the procedure, and the distillation data obtained are used to compute the approximate amounts of products present in the sample--such as percentages of gasoline, kerosine, gas oil, and lubricants. The principal data and results are recorded on a standard analytical report form. An analysis of a sample of crude oil from a recently developed field is shown in table 1. Compilations of these analyses, sometimes in tabular form and usually for specific geographic areas, are published from time to time. Analyses often are included in connection with other studies, such as engineering field reports.

Jan 1, 1959

The Minerals Data Source Directory is a compilation of descriptive information on the availability, content, and location of minerals data in the Federal Government. It is intended to assist Government personnel and the general public in locating and acquiring minerals information. Included in the Directory are descriptions of data bases, publications, information systems, and information offices containing data pertaining to all aspects of mineral production, consumption, trade, and related information. These mineral data sources include the Federal agencies such as the Department of the Interior's Bureau of Mines and Geological Survey whose major mission is the collection and dissemination of mineral information. Also included are agencies such as the Departments of Agriculture, Commerce, Labor, State, and Treasury, and the Central Intelligence Agency, whose primary mission is the collection of data in non mineral subject areas, but in which the mineral industry is a component.

Jan 1, 1982

By A Rorke, B Cubitt, R Beeslaar

The recent drop in the value of the South African Rand has resulted in an increased export value for South African coal and has lead to new coal reserves becoming available for mining. Very often these reserves are in close proximity to existing structures and utilities thus calling for stringent blast control measures to keep the risk of vibration, air blast and fly rock damage to a minimum.

Jan 1, 1997

Study on Oil Agglomeration Flotation for Deinking

Sep 13, 2010

By Philip K. Hopke

A systematic study of the mechanism of interaction of 218Po(RaA) armed by the decay of 222Rn with airborne particulate matter has been made. The rate of attachment of RaA to particles in the diameter range of 0.1 µm to 10.0 µm has been measured as a function of particle size, concentration, and composition, radon concentration, time of interaction, relative humidity and temperature. It was found that under the conditions in these experiments the attachment rate was proportional to the square of the particle diameter and varied with temperature and relative humidity. The composition of the particles apparently has no effect on the attachment. The variation in attachment rate was related to a sticking probability coefficient of approximately 0.02 that varies systematically with temperature and humidity. In addition, the rate of deposition of RaA on the wall of the attachment kinetics system was measured and also found to change with temperature and relative humidity.

Jan 1, 1980

By Ravi Ray, Kostas Kaklis, Zach Agioutantis

"Modern underground mining is becoming more complex and geotechnically challenging. The engineer uses numerical, analytical, and data-driven methods (empirical and/or experimental) or their combination to overcome these challenges. Each method has its advantages and disadvantages. Nevertheless, given the amount of innovation and experience involved in developing each of these techniques, it will be prudent to use all their benefits rather than favoring one technique over the other. Pillars are the most important support element in an underground mine. A holistic geo-mechanical solution needs to be determined to design mine pillars using a proper sequence and exact mix of the three methods. A combination of these methods, in sync, can encompass the several advantages of the three methods while eliminating their disadvantages. This paper presents a conceptual three-tier solution to the pillar design problem, to improve its design pedigree, using a proper combination of numerical, analytical, and data-driven methods. At the focus of this proposed method lies the Ground Reaction Curve (GRC) concept.INTRODUCTIONAlthough the stability analysis of underground excavations is a challenging problem, its understanding has improved tremendously over recent years through the use of improved tools and techniques. The trial and error method was replaced with more scientific methods like the empirical and analytical methods that are still in use today. Empirical methods were developed based on large data sets obtained from experiments and observations (e.g., coal pillar strength equations). Analytical methods were developed based on mechanical understanding of stability (e.g., safety factor for vertical pillar loading, Convergence Confinement Method). Improvement in computing power and numerical techniques led to the development of several numerical methods (e.g., finite difference, finite element) suitable for geo-mechanical analysis.Each of these methods have certain advantages and limitations. Nevertheless, the user is often puzzled over the proper method selection and over the proper sequence of using them. This exercise becomes more challenging when different methods are combined, where, for example, one has to estimate the pillar strength based on empirical equations (e.g., Mark-Bieniawski coal pillar strength equation), determine the factor of safety based on an analytical approach (e.g., tributary area load divided by pillar strength), and analyze pillar-strata interactions using numerical analysis (see Esterhuizen, Mark, and Murphy, 2010b).Challenges increase when current pillar design methods are designed as passive structures to balance the fixed dead weight of the overburden. This classic suspension design approach does not recognize the self-stabilizing capacity of the overburden (Frith and Reed, 2018). A practical solution to address these issues is the use of numerical analysis. However, one should always keep in mind that the numerical modelling approach may have certain practical limitations."

Jan 1, 2019

By Gartrell H. W

During investigations of the treatment methods for ore from the Bird-in-Hand gold mine carried out at Kalgoorlie and at these laboratories, it was found that excess alkali caused a lowering of extraction by cyanide, the cause of this being attrIbuted to the presence of a small amount of oxidised lead compounds in the ore. The subject has been discussed by various writers,3 but no satisfactory explanation of existing facts has been put forward. The experiments described in this report have been carried out with the object of obtaining some insight into the chemical reactions underlying the effect of lead salts and alkalis in cyanidation.The formation of cyanide-insoluble coatings on gold during roasting with lead compounds is well known, but the adverse effect of alkalis in cyanidation of ore is *This paper represents work done under a co-operative agreement between the Commonwealth Council for Scientific and Industrial Research and the South Australian School of Mines and Industries.Published by permission of the Mining Advisory Committee, Commonwealth Council for Scientific and Industrial Research.

Jan 1, 1935

By Rayleen Riske

Why do we look for better reconciliation when times get tough? Why wait? Mine reconciliation should be a priority throughout the good times too. In fact, with good reconciliation, those good times are going to be even better and will help pave the way to success through those preventable bad times. Reconciliation throughout the entire mining value chain requires the capture, validation, and analysis of copious amounts of data. This task can be daunting for a team in a small mine, let alone reconciling across a suite of large mines. This paper will outline the different ways we can reconcile across the value chain, why we should reconcile over differing periods of time and how Snowden?s solution to proving reconciliation can be a simpler, reliable and transparent process. Snowden?s Reconcilor is proving to be a valuable tool on any mining scale, by capturing, validating, sorting and reporting data for timely decision making by the site geologist through to corporate management. By instigating vigorous reconciliation, you are setting your mine up for the future. Not only will you have the means to analyse your current processes and measures, but you will have the opportunity to identify and improve your mine?s performance from the resource model through to the final product.

May 1, 2010

By G. A. Mallory

"The South Bay Division of Selco Mining is located fifty-four miles northeast of Ear Falls Ontario on Confederation Lake. The concentrator operates five days a week and processes six hundred tons per day of copper zinc silver sulphide ore. The concentrator is comprised of crushing, grinding, differential flotation, thickening and drying circuits. The major constituents of the concentrator feed are: chalcopyrite 7%, sphalerite 20%, pyrrhotite 3%, pyrite 25 - 30% and felsitic volcanics 40 - 50%. The mine went into production in March 1971 with an anticipated three year life and is now scheduled for closure in the summer of 1981. Recent mine production has been limited to three cut and fill stopes which have widely varying ore grades, therefore mill feeds vary from 0.25 to 4% copper, 3.5 to 27% zinc, 0 to 0.4% lead and 15 to 30% iron.In mid 1977 Selco negotiated a six month rental purchase agreement with Outokumpu Instruments Canada Limited for a five stream analyser system. The Minexan 202 probes were the first Outokumpu probe type analysers installed in Canada although Outokumpus' Courier systems are well known. Installation of the system took place in April 1978 and after numerous hardware faults the six month evaluation began in August. By December it was obvious that the Minexan 202 probes with proportional detectors did not have adequate resolution to determine low copper values in either of the tailings streams. Outokumpu offered to replace the tailings analysers with a new prototype solid state detector probe the following summer. The evaluation on the five Minexan 202 probes continued until August 1979 when the new solid probe was installed. The Minexan S (solid state) probe was evaluated with the three remaining Minexan 202 probes until December 1979 when Selco elected to purchase the system."

Jan 1, 1981

By Clarence Karr

THE BUREAU OF MINES is investigating methods for upgrading tar produced by the low-temperature carbonization of bituminous coal. This survey was undertaken to compile information needed for identifying the ether constituents of low-temperature tar. Physical properties are listed for 1,024 aromatic ethers. The compounds include cyclic and noncyclic, polyfunctional and monofunctional ethers with oxygen joined directly to either one or two aromatic rings. Alkyl groups up through butyl are included. The compounds are divided into 37 groups ranging in complexity from alkoxybenzenes to dibenzopyrans. Compounds containing aromatic ether groups are important constituents of the neutral oxygen components of low-temperature tar. For example, at Morgantown, W. Va., the Bureau of Mines has identified and determined the amounts of benzofuran, 2-, 3-, 5-, 6-, and 7 -methylbenzofuran, diphenyl ether, dibenzofuran, 2,3-dimethyldibenzofuran, and two other dimethyl-dibenzofurans in the neutral oil from a low-temperature bituminous coal tar (103, 104).3

Jan 1, 1962

By Dale R. Ralston

This investigation was divided into two major phases. Phase I of the study was an examination of the occurrence and production of acid water within the Bunker Hill Mine in northern Idaho. The second phase of the project involved the study of water movement through an abandoned tailings pile. Mineralogy and hydrogeology were determined to be the two most important factors in the acid mine drainage problem. Low pH water was formed in the mine in areas of lead-zinc ore rich in pyrite. Water movement in the mine was important in the production of acid and the transportation of heavy metals. Areas of recharge to the mine were identified. A data collection network was installed to monitor water quality and quantity changes. The quantity of acid drainage from the mine was found to vary directly with surface runoff events. The study of the abandoned tailings pile was performed to determine the characteristics of water movement through the tailings material and the resultant impact on the hydrologic environment. The Page Tailings Pile, abandoned in 1969, was utilized as a study area. An extensive network of piezometers and meteorological data collection sites were installed in and near the pile. Data collected to date indicate the presence of a ground-water mound under the east half of the pile. Some transfer of ions from the tailings pile to the ground-water system has been detected.

Jan 1, 1973

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 D. Xie

An in situ gravimetric technique based on wetting and capillary action principles has been used to investigate the wetting and penetration of synthesized alumina samples and commercial magnesia spinel refractories by CaO-SiO2-Al2O3-Fe2O3slags. Synthetic slags of 40CaO-40SiO2-20Al2O3 (in weight per cent) with 0 to 9 weight per cent Fe2O3were used and the experiments were conducted at temperatures 1370 to 1470ºC under argon. The contact time between the sample and the slag was 30 minutes. The results show that the wetting and penetration are enhanced by the iron oxide addition in the slags. Addition of Fe2O3from 0 to 9 weight per cent resulted in a significant increase in the slag penetration into the magnesia spinel refractory by a factor of about 7 and a moderate increase in the synthesized alumina by about 60 per cent. The addition of Fe2O3enhanced the wetting (??cos?, where ? is the surface tension of the slag and the contact angle between the slag and the refractory) by 5 to 18 per cent. An increase in temperature from 1370ºC to 1470ºC resulted in a significant increase in the penetration of a 6 weight per cent Fe2O3slag in the alumina and magnesia samples by a factor of4 to 5 and a decrease in wetting by approximately 30 per cent. Keywords: refractories, slag penetration, wetting.

Jan 1, 2004