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By R. L. Brown

This report, the seventeenth in an annual series, summarizes Bureau of Mines research and technologic work on coal and related investigations for July 1, 1951, to July 1, 1952. It 1s based largely on publications issued during the fiscal year, although 10 some instances data are presented that have not been published previously. Footnote references are given to the publications so that further details on the work may be obtained. Bureau of Mines research on the mining, preparation, and utilization of coal is directed toward developing and encouraging safer and more efficient mining practices and preparing and utilizing coals to the best advantage.

Jan 1, 1953

By F. S. Crawford

Although it may be impracticable to adopt standard methods of safe working in all branches of mining, and although it may be impossible to establish a standard for each class of work at each mine, some of the iron-mining companies in the Lake Superior district have found that by adopting certain standard ways of performing certain of their operations they insure both more efficient and safer working conditions. Many companies have adopted the idea that the safe way of doing things is also the most efficient and economical way, and, through the medium of their safety conferences they are trying to find the safest way, and the most efficient way, of performing practically every operation about the mines. This activity will, undoubtedly, be continued at every operation which uses this method of doing safety work, because in the advance of industry changes must be made in the results required from time to time. A review of the safety standards and safety suggestions which have been arrived at by some of the companies in this the greatest iron-mining district in the world, will be of value to companies who are interested in improving the safety of their working conditions. So that attention may be directed to the methods in use, rather than to individual companies, all names have been omitted and companies are referred to only by letter.

Aug 1, 1931

This report is the 23d in a series summarizing research and technologic work by the Federal Bureau of Mines on coal and related investigations; it is the fifth report to be issued on a calendar-year basis.2/ Publications by Bureau personnel in 1958 are cited;3/ in addition work in progress during the year is briefly described. To conserve our reserves of coal the Bureau of Mines conducts a program concerned with the development of fundamental information on coal characteristics and behavior, and the improvement of technology related to its production and utilization. The ability to anticipate and meet future demands for coal depends on a number of factors: (1) Knowledge of reserves from a stand- point of both quantity and quality; (2) the development of improved mining methods, health and safety measures, and preparation techniques that will insure its most efficient exploitation; and (3) knowledge of the controlling factors in efficient use of coal in combustion, carbonization, gasification, direct and indirect hydrogenation, and other new processes. The Bureau is concerned with each of these areas.4/,5/

Jan 1, 1960

By V. E. Edlund

As part of its efforts to devise new and improved methods for recovering lithium from unconventional resources , the Bureau of Mines investigated a lime -gypsum- roast , water- leach technique for processing lithiumenriched ( 0.01-0.68 pct Li ) clays . This report presents the results of a study of the technical feasibility of extracting lithium from raw material representative of clay beds associated with the McDermitt Caldera complex in Nevada and Oregon . prepared from water used Pellets suitable for bench-scale roasting studies were mixtures of minus 200 -mesh clay , limestone , and gypsum , with as the pelletizing agent . Roasting pelletized charges at 900 ° to 1,000° C temperatures for 1- to 4-h periods produced calcines that leached readily , yielding water - soluble lithium sulfate ( Li₂SO4 ) . A 5-3-3 ( weight ratio ) mix of clay , limestone , and gypsum produced calcines with the best leaching characteristics . More than 91 pct of the contained lithium was extracted from pelletized mix batches roasted in covered refractory boats . Lithium recovery decreased to about 87 pct when the mix was roasted under dynamic conditions in a gas - fired rotary furnace . A reaction mechanism was postulated which indicated that dilution and loss of SO2 and oxygen in the combustion exhaust adversely affected the leachability of the dynamically roasted calcine .

Jan 1, 1983

By A. W. Fahrenwald, W. W. Staley

"In flotation concentration, various machines are employed for agitation and aeration of the ore pulp in the operation of frothing. The power required in the operation of these machines varies considerably with the type and make of machine used. The object of this investigation was to determine the effect of certain physical properties of the pulp particularly viscosity, density, and temperature - upon the power required by certain forms of pulp agitators.The viscosity factor is most involved because it is affected by temperature and by density. Viscosity of liquids and suspensions has been extensively studied and the physics and mathematics of the subject are much enlarged upon in books and in the literature. It is not, however, the intention of this study to become involved in the intricacies of these phases of the subject.The agitation of the various mediums in the experimental work did not last long enough to cause a measurable rise in temperature from the ""beating"" of the medium, hence no cognizance is taken of this factor.No attempt has been made to correlate the data obtained with the impeller with any information regarding centrifugal pumps. The object sought here is quite foreign to the problems of pumping. The impellers used are ""open"" and air is involved.The experiments performed and the data obtained are presented. Only that amount of discussion necessary to make the results understandable is given.Tap water was used in all experiments. A comparison of distilled water and tap water showed no measurable difference. In the experiment in which sodium chloride was needed, the commercial salt as used in fire assaying was taken. The quartz was of the ""bull quartz"" variety, thoroughly washed free of iron oxide."

Jun 1, 1930

By Charles M. McCulloch

This Bureau of Mines report discusses the principles of using computers to draw maps and plot geologic data of mining areas. The types of maps that can be drawn by a computer are reviewed, using as examples two separate areas where poor roof and gas emissions caused mining problems. Such maps can be used not only to help identify problem areas, but also to predict areas where problems could occur, thus giving mine operators time to work out solutions prior to mining. The average cost of a computer-drawn map for a mine property is less than $100, including computer time and man-hours for data preparation.

Jan 1, 1976

By William E. Eckard

Production of oil from a narrow shoestring sand presents problems unique in the oil industry. Especially important, from both an engineering end an economic standpoint, are the limitations imposed upon well patterns and spacings by the shape of the field. This report concerns a study of the Paola shoestring, Miami and Franklin Counties, Kane., where well density of 0.85 acre per well was not uncommon to insure profitable primary recovery in a reasonable time. However, such a great number of wells increased the operator's investment and reduced his profit considerably. It was the purpose of this study to investigate various well patterns and spacings applicable to water-flooding a shoestring reservoir and the effect of these factors upon recovery of oil and the most profitable operation of the pool. The designer of well patterns for a shoestring sand should evaluate carefully the edges of the shoestring, even though they may be considered too thin to drill. These comparatively thin edges contain large quantities of recoverable oil; moreover they are resaturated with oil as the pool is water-flooded.

Jan 1, 1951

By L. Cheng

This report describes a laboratory investigation of the effectiveness of low-pressure steam and a steam-water spray sequence for the collection of airborne respirable (<10 µm) coal dust. Comparison of present results to previous results obtained with water spray alone indicates that the use of steam in a steam-spray sequence increases the collection efficiency by about 14 percent over that obtained by water spray alone. However, the use of steam to collect airborne dust requires cooling the steam-dust mixture in order to achieve condensation of the steam, and steam does not appear to be an attractive approach for collecting airborne dust in underground coal mining operations.

Jan 1, 1974

By R. Clark Lantz, Charles Stanley, David E. Hinton

Morphometric examination of lung alterations following exposure to toxic and pathogenic substances is invaluable in detecting subtle changes which might otherwise be overlooked. Results, from evaluation of initial structural alterations, support and guide subsequent nonmorphological techniques and, when coupled appropriately, can lead to a better understanding of the pathogenesis of a disease. Morphometry is a technique which can be used to determine, quantitatively, the site, extent, development, and progression of a disease state. Determination of the extent of tissue and cellular involvement in the response to inhalation of silica has been performed in order to gain a better understanding of the development of fibrosis following inhalation of this toxicant. In addition, since silica has been postulated as one of the important pathogenic minerals in coal mine dust' it is important to understand the lung tissue response to silica prior to evaluating the effects of inhaled coal mine dusts. Male Syrian golden hamsters were placed in Hazelton 1000 inhalation chambers and were exposed to either filtered air (controls, n = 24) or filtered air plus 30 mg!m3 silica (Min-U-Si110,95%ofparticles < 5 um,n =24)for16hours per day, five days per week, for two weeks. Animals were returned to the animal quarters prior to subsequent tissue processing at 1, 4, and 12 weeks following exposure. This schedule was designed to allow time for the development of fibrosis. Lungs were fixed by intratracheal perfusion of ½ strength Karnovsky's fixative at a pressure of 20 cm H20 and tissues were taken for embedment and analysis at the light level. Determination of site, extent, and development of alterations was performed using a multitiered approach. Changes in large structures (airways, blood vessels) was determined prior to evaluation of changes at the septal tissue level. Data will be presented outlining the progression of changes. Results indicate the usefulness of morphometric analysis of lungs following inhalation of toxic substances in quantitatively defining the structural alterations.

Mar 1, 1989

By I. L. Nichols

Volatilization of cesium from pollucite ore was investigated as an initial step in the production of purified cesium metal or cesium salts. High recovery of cesium and rubidium as chloride sublimates was accomplished by 2-hour roasts in a tube furnace using charges containing 1 part ore, 2 parts limestone, and 0.23 part calcium chloride. Recoveries of cesium in the sublimate product were 89.1, 92.9, and 95.2 pct, respectively, using 1,100° C and vacuum, 1,250° C with an air sweep, and 1,250° C without an air sweep. Most of the lithium, sodium, and potassium sublimed with the cesium and rubidium, but virtually none of the calcium, aluminum, and silicon in the charges was volatilized.

Jan 1, 1966

By Arnold O. Tanner

The domestic mining industry gained more strength in 1988 as the healthy comeback that became evident in 1987 continued and grew for many commodities. The increasing and more stable commodity prices, still predominantly in the metals sector, reinforced both the new ways of conducting business and the use of technological advancements in successfully lowering operating costs during the last 4 to 6 years. Some commodities and companies still struggled to survive, but increases in productivity and profits were becoming more common.

Jan 1, 1990

By Sidney Katell

Tonnage oxygen plants are or can be made available in sizes ranging from 150 to 1,000 tons per day. Capital requirements are estimated from $5,400 to $14,700 per daily ton, depending upon size of plant, cycle employed, and purity and discharge pressure of the product. Similarly, operating costs before return on investment will range from $4.80 to $10 per ton. INTRODUCTION Several processes4 5/ that can be used to convert coal to synthetic liquid fuels, synthetic pipeline gas, or hydrogen require high-purity oxygen as one of the basic raw materials. Depending on the and product and its specific use, the oxygen required will be of 95 or 99.5 percent purity. The quantity required, in turn, depends on the process for which the oxygen will be used and the size of the processing plant and will range from 150 to 4,000 tons per day.

Jan 1, 1960

By G. M. Kintz

The data in this circular were taken from publications of the United States Bureau of Mines and published annual reports of the Wyoming State Inspector of Coal Mines. The tables included are complete only&apos; with regard to major disasters; the Bureau of Mines considers a major disaster one in which 5 or more men are killed. However, minor disasters and gas ignitions recorded in these publications are included. It is known that a number of gas ignitions have occurred of which no record is available. This is one of a series of papers by the Bureau of Mines giving by States available data regarding coal-mine explosions. This information is published in condensed form in the belief that it may be of vale to mine operators in preventing future coal-mine explosions.

Jan 1, 1934

By R. Ward Stahl

This publication is a revision of Report of Investigations 5363 updated to reflect the improvement in fire protection at selected coal mines and contains suggestions on what may be considered good fire protective equipment, suggested methods of organizing the attack on fires at various locations underground, and helpful hints on testing and evaluating firefighting facilities.

Jan 1, 1968

By Christopher Van Dyke, Edward L. Petsonk, Knox Van Dyke, Vincent Castranova, Ji-Hee Kang, William Pailes

"INTRODUCTIONPlatelet-activating factor (P AF) has been shown to mediate a broad range of biologic activities (1). Chemical analysis has shown that PAF is a glycerophospholipid with a choline polar head group, an ester-linked acyl chain at the second carbon of the glycerol backbone, and an ether linkage at the first carbon. The alkyl group attached to the first carbon can exist in a variety of chain lengths, with the C16 and C18 forms predominant in humans. The structure of P AF has been identified as 1-0-alkyl-2-acetyl-sn-glycerol-3-phosphorylcholine (2,3).PAF can be released from a variety of cell types, such as basophils, neutrophils, and alveolar macrophages ( 4-6). Stimuli for the release of P AF include calcium ionophore, phorbol esters, chemotactic agents, and zymosan. In addition, endotoxin has been shown to be a potent stimulant of P AF release from alveolar macrophages (7).P AF has been shown to have a number of pulmonary effects. It has been associated with asthma since it can cause contraction of pulmonary tissue (8) and leukotriene secretion from leukocytes (9) and induce airway constriction when inhaled by humans (10). In addition, PAF is a potent chemoattractant and can cause migration ofneutrophils into the airspaces of the lungs (11,12). Endotoxin is a lipopolysaccharide-protein complex derived from the cell walls of gram-negative bacteria. I.PS is the lipopolysaccharide portion of endotoxin. LPS contains four covalently joined subunits: lipid A, 3-deoxyoctonate, a core polysaccharide moiety, and an 0-specific antigenic polysaccharide side chain. Rough LPS contains no 0-antigen side chain. The liP.id A portion of LPS has been associated with most of the biolQgic effects of endotoxin (13). This lipid A subunit consists of a D-glucosamine disaccharide backbone substituted with four fatty acid side chains. Endotoxin is found in a wide variety of occupational settings associated with organic dusts derived from plants or animals, such as cotton, cereal grains, silage, rice, and poultry (14-18). In addition, airborne endotoxin has been found in sewage treatment plants, composting plants, offices with contaminated humidifiers, and showers or saunas (19-22)."

Jan 1, 1990

By Jack D. Ramsdell

Electrorefined, magnesium-reduced, and sodium-reduced titanium samples were evaluated for recrystallization behavior, effect of cold rolling on tensile properties, and bend ductility. Curves were determined for the softening of 2.5 to 80 percent reduced cold-rolled metal that was annealed over a temperature range of 300° to 800° C. Upon annealing, coarsening of the grains was found to occur for reductions in thickness of less than 20 percent in titanium made by all three processes. The presence of metallic impurities greatly inhibits coarsening for reductions in thickness below 20 percent, but for reductions in excess of 20 percent grain size is essentially constant at each annealing temperature. The three grades of titanium did not harden excessively from cold rolling; both tensile and bend ductility were good for reduction in thickness up to 80 percent. Upon annealing, softening occurs between 400° and 600° C., and, based on microstructure and property studies, full annealing is accomplished after 30 minutes at 700° C. for the magnesium-reduced and electrorefined titanium and at 800° C. for the sodium-reduced titanium.

Jan 1, 1960

By E. E. Maust

The literature on the activation of sphalerite for flotation by short¬chain xanthates leaves unanswered the question of whether a compact surface film of activator sulfide is necessary or merely sufficient for high flotation recoveries. Studies by Guarnaschelli and Plaksin indicate that xanthate adsorption and flotation of sphalerite are increased with increasing hole/ electron ratio. These results, and the known acceptorlike behavior of many heavy-metal impurities in zinc sulfide, suggest that activation may result from a traditional semiconductor doping effect at the surface. Using the theory of chemisorption states on ionic crystals as developed by Levine and Mark, the Bureau of Mines has carried out A calculation to estimate the surface-state energies of various metals when they are substituted at zinc sites on (110) sphalerite surfaces. Based on a simple Madelung-Born treatment of ionic solids, the calculation indicates that many of the metals known to activate sphalerite for subsequent flotation have lower surface-state energies than nonactivators. The results of these calculations are discussed from the standpoint of consistency with the proposed activation mechanism and observed flotation results. The satisfactory agreement obtained is taken to be support for the proposed mechanism, and further elaboration of a surface-doping model is attempted.

Jan 1, 1976

By W. T. Westbrook

This Bureau of Mines report contains methods for analyzing iron are for total iron, ferrous iron, metallic iron, silica, manganese, aluminum, calcium, magnesium, phosphorus, titanium, carbon, sulfur, moisture loss, and ignition loss by wet chemical methods. Some are modifications of standard umpire methods; others have been developed by the Bureau of Mines to provide a com-bination of speed and accuracy. They are suitable for a high volume of samples and/or control situations, and for situations in which instrumental results must be verified. These methods have been used to analyze taconites, native ores, some foreign ores, and metallurgical products.

Jan 1, 1975

By W. L. Acherman

Molybdenum, tungsten, and vanadium were found by the Bureau of Mines to possess generally superior chemical and galvanic corrosion properties in many aqueous corrosive media at temperatures up to the boiling point. The corrosion resistance of vanadium in certain solutions was further improved by alloying it with such metals as columbium, tantalum, and titanium. was susceptible to a type of crevice corrosion in mercuric chloride solutions, but no other instances of crevice corrosion were encountered. With few exceptions, molybdenum, tungsten, and vanadium were not adversely affected when coupled with dissimilar metals in galvanic corrosion experiments; in some cases one or both members of a couple were protected by contact. When exposed to aqueous ammonia spray at 60° C, all three metals were attacked, but they were moderately resistant in spray environments of substitute ocean water and ammonium dihydrogen phosphate.

Jan 1, 1966

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 instructions2 issued by the Bureau of Mines; the samples are analyzed in the Bureau laboratory to determine whether the coal is of the quality guaranteed by the contractor; if it is not, a price adjustment is made, Analyses of the delivered coal and tipple samples (samples collected at mine tipples as coal is being loaded into railroad cars or trucks) provide valuable data for use in evaluating future bids. In addition, the continuous sampling of coal as delivered is a check on the practical results obtained in burning the coal.

Jan 1, 1971