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By James J. Dowd

The investigation to evaluate the reserves of coking coal is being made by the Bureau of Mines in three parts: (1) To estimate known (measured plus indicated) recoverable reserves of all coking coal; (2) to upgrade marginal coals through effective preparation; and, (3) to study the carbonizing properties of coal and coal blends not now widely used for metallurgical coke. This is the third of a series of reports giving results of studies by counties under part (1) of the investigation. This report covers Pike County, Ky., which comprises parts of the Harold, Williamson, Matewan, Gilbert, Pikeville, Regina, Hurley, Pound, and Clintwood quadrangles. (See fig. 1.) A base map for each bed in each quadrangle was made to the scale of 1 inch equals 1,200 feet. Maps of mines, locations of drill holes, bed and total coal thicknesses, and the outcrop of the bed were plotted on the maps. With all available data plotted, isopach lines were drawn to limit areas of known unmined reserves in beds 0 to 14 inches thick, 14 to 28 inches thick, 28 to 42 inches thick, and over 42 inches thick. These areas of coal reserves also were divided into "measured" and "indicated" categories. All areas in each thickness range and in each category, mined-out areas, areas excluded from the estimate but which may contain reserves based only on geologic inference, and areas outside of the outcrop were measured by planimeter on the base maps. Estimates of total reserves 14 inches and more thick and maps for individual beds were prepared from these data.

Jan 1, 1951

By J. H. Welsh

This Bureau of Mines report presents guidelines to be considered in the design, installation, and operation of environmental mine monitoring systems in underground coal mines so as to enhance safety in the U.S. mining industry. A review of the current status of mine monitoring in the United States is also provided.

Jan 1, 1987

By Thomas M. Barczak

Purchasing a new set of longwall shields requires a substantial investment. A poor shield design can lead to economic hardships, safety concerns for the mine workers, and closure of the mine. This paper addresses several key points that should be considered in the procurement process: (1) understanding your goals and the logic in selecting a higher capacity shield, (2) the importance of completing performance testing before production shield fabrication begins, (3) making sure performance testing is properly done, (4) measuring load(stress) development during performance testing, (5) testing a shield to failure, and (6) the value of buying extra shields. In addition, several challenges are proposed for consideration in future shield designs. These include (1) 100,000 life-cycle expectancy, (2) improved hydraulic diagnostic capability, (3) smart load control by optimizing setting pressures, (4) lubricated link joint design concepts, (5) composite material applications to reduce shield weight, (6) incorporating periodic weighting predictive algorithms into the data-processing software, (7) advanced component load measurement on two to three specially instrumented shields to detect loading in the structural components, and (8) constant set leg cylinder design.

Jan 10, 2000

By James Westfield

This publication covers the work of the Division of Coal Mine Inspection, Bureau of Mines, as performed under provisions of the Federal Coal Mine Safety Act. It presents background information and data since 1952 when the Act became effective and includes up-to-date statistics for the calendar year 1962. During that year, approximately 9,704 coal mines were active in the United States, and the Bureau made 12,810 regular inspections. BACKGROUND The Federal coal-mine inspection program was established to carry out the provisions in Public Law 49, 77th Congress, (H. R. 2082) approved May 7, 1941. This act has since been amended as Title I, Advisory Powers Relating to Health and Safety Conditions in Mines, under Public Law 552, 82d Congress, approved July 16, 1952, which also included Title II, Prevention of Major Disasters in Mines. Public Law 552 is known as the Federal Coal Mine Safety Act.

Jan 1, 1963

By David E. Nicholson

This report investigates the mechanical behavior of fine soils in a lunar environment in engineering gravity-flow bins. The ultrahigh vacuum, absence of moisture, and a lunar gravity one-sixth that of earth gravity represents a unique environment, both advantageous and detrimental to these systems. On earth, moisture and gases contained in powder masses can be responsible for complex descriptions of gravity flow. Their absence appear to simplify the lunar soil behavior. However, simulation of the lunar gravity and vacuum complicates the development of experimental data for designing bins. The properties of a dry soil powder, its behavior under one-dimensional compression, and its torsional and direct shearing strength under earth atmosphere are described in part 1 of this paper. These properties provide the parameters for a finite-element analysis to optimize the design of bins, to be described by Dr. William Pariseau in part 2. Shear tests assess the failure criteria for the material. Compression tests provide modulus and (Ko) stress-ratio values from the loading portion of the compression cycle, duplicating the condition of a bin at rest with the discharge closed. During the unloading portion of the compression cycle (soil overconsolidated), the residual Ko values rise. It is postulated that this phenomenon creates a high-lateral stress in bins when they approach incipient flow. Assessment of the Ko value, overconsolidation ratio, and the void ratio state is proposed as a criterion to determine the flowability of powder.

Jan 1, 1971

By Michael E. Henderson

The U.S. Bureau of Mines (BOM) constructed the Hydraulic Transport Research Facility (HTRF) to investigate the hydraulic parameters relating to the transport of coarse coal. To achieve these goals in a timely and efficient manner, the Bureau contracted to Boeing Services International, Inc. (BSI) the responsibility of operating the HTRF and providing technical support. This data report is a summary of the testing and data results for the period from 16 September to 1 November 1983. The testing covered herein is for coarse 2-in by a (minus 50 mm) Pittsburgh Seam coal in a 12-in (3 00 mm) pipeline, at velocities ranging from 5 to 18 ft/s (1.5 to 5.5 m/s) and at concentrations ranging from 15 to 55 pct.

Jan 1, 1985

By Joan T. May

The Federal Bureau of Mines investigated the potential for recovering aluminum from copper-dump leach liquors by use of single-contact ion-exchange technology. A strongly acidic ion-exchange resin was used to extract aluminum from a typical dump leach liquor and from synthetic leach liquors. Aluminum was stripped from resin with a HS04 or NaCl solution. Bench-scale experiments indicate that a single-contact ion exchange is technically feasible, but that the process is limited by the relatively low loading capacity of the resin and the excessive amount of stripping agent required. A further limitation is that significant amounts of magnesium and iron are loaded and stripped along with the aluminum.

Jan 1, 1976

By A. W. Decora

Gas-liquid chromatography has been applied to separating basic nitrogen compounds, such as pyridines and amines. Close-boiling compounds have been separated by exploiting structural and polarity differences, using selective liquid substrates dispersed on specially prepared solid supports. Development of these special supports was necessary in order to obtain symmetric peaks for basic nitrogen compounds; solution of this problem was important in applying gas-liquid chromatography to the analysis of basic nitrogen compounds found in shale oil. Attempts to analyze shale-oil tar bases by conventional gas-liquid chromatographic techniques, using Chromosorb4/ or Celite 545 as the support for a nonpolar liquid substrate, resulted in asymmetric peaks. These asymmetries were caused by adsorption of sample vapors on the solid support. Symmetric peaks were obtained when strongly polar liquid substrates were used on either Chromosorb or Celite. However, a solid support giving symmetric peaks only with strong polar substrates restricts the choice of substrate, and frequently, desired separations cannot be achieved.

Jan 1, 1961

By Jr. Watts, B. K. Cantrell, D. H. Carlson, K. L. Rubow

"The use of diesel equipment in underground coal mines is controversial because ""whole diesel exhaust"" is regarded as ""a potential occupational carcinogen"" by the National Institute for Occupational Safety and Health (NIOSH). Threshold limit values (TLVs) are recommended for the gaseous pollutants; CO, CO2, NO, NO2, SO2, and some hydrocarbons emitted in diesel exhaust. There is, however, no TLV recommended for diesel exhaust aerosols (DEA) nor is there a standard method for sampling these aerosols.The University of Minnesota and the Bureau of Mines have collaborated to develop a personal diesel exhaust aerosol sampler (PDEAS) which utilizes size selective, inertial impaction and gravimetric analysis. During the field tests of this sampler, numerous air quality measurements were conducted in underground coal mines using diesel equipment. The objective of this report is to present these data and to assess the impact of diesel face haulage equipment on mine air quality.Air quality data were collected in four underground coal mines using continuous mining methods with diesel haulage equipment. Daily samples were collected at the section intake, haulageway, and on haulage vehicles. Both full-and partial-shift samples were collected using a variety of aerosol instruments, including the PDEAS and the micro-orifice, uniform deposit impactor (MOUDI) which sample the mine aerosol diesel exhaust fraction. Two of the mines were also monitored for the major gaseous constituents found in diesel exhaust CO, CO2, NO, NO2, and SO2. These measurements were made by either collecting bag samples for subsequent gas analysis or by Palmes dosimeters.The concentrations of CO, CO2, NO, NO2, and SO2, were well below regulated levels. The mine average DEA concentration determined by the PDEAS in the haulageway for the three mines surveyed using this instrument was 0.79 mg/m3, with a standard deviation of 0.19 mg/m3. DEA contributed 65% of the respirable aerosol, at this location. These results were the same as the mean DEA concentrations calculated from size distribution measurements obtained using the MOUDI. This was 0.78 mg/m3, with a standard deviation of 0.22 mg/m3."

Mar 1, 1992

By A. Landsberg

Kaolinitic clays are potentially a vast domestic resource for aluminum. Utilization of this resource could decrease or eliminate the nearly complete dependence of the United States on foreign raw materials for this important metal. Furthermore, processing of clay to aluminum through anhydrous chloride metallurgy could reduce the high electrical energy requirements of the conventional Hall-Heroult aluminum reduction process. Several anhydrous chloride processes have been proposed; however, unresolved technical problems have prevented their commercialization. In particular, an acceptable chemical means has not been found to extract aluminum from clay as a highly pure anhydrous aluminum chloride. This Bureau of Mines report identifies and discusses the important chemical problems involved in achieving an acceptably rapid, self-heating, selective chlorination reaction and the subsequent separation of iron chloride byproduct from the anhydrous aluminum chloride.

Jan 1, 1983

By J. Dean Warner

In 1984, as part of a project to evaluate Alaskan occurrences of certain critical and strategic minerals, the Bureau of Mines investigated a columbium-bearing regolith on upper Idaho Gulch, near Tofty, AK. The regolith is derived from weathering of a dolomitic marble and consists mostly of iron oxide minerals with accessory apatite, zircon, xenotime, rutile, monazite, and the columbium minerals aeschynite, columbite, and ilmenorutile. Two regolith lenses contain 340,000 lb of columbium resources at an average grade of 0.07 pct. Calculated composite concentrates from two regolith samples (approximately 200 lb each) contained 53 and 57 pct of the columbium at grades of 0.97 and 0.86 pct, respectively. In each case the grade could be improved to 1.1 pct Cb with a sacrifice of 9-pct recovery. The regolith's mineralogy, trace-element geochemistry, and similarity to descriptions of other columbium-enriched regoliths suggest that the underlying marble may be a carbonatite. The lack of associated alkalic igneous rocks and the stratiform nature of the regolith, however, may be interpreted as evidence for sedimentary origin of the marble. The marble and regolith are a lode source for some of the minerals in the Idaho Gulch placer deposit.

Jan 1, 1986

By W. F. Marshall

This report describes exhaust-emission data from 10 diesel engines: six 4-cycle, direct-injection, naturally aspirated engines; two 4-cycle, direct-injection, turbocharged engines; one 4-cycle, precombustion-chamber, turbo-charged engine; and one 2-cycle, direct-injection engine. These engines were tested over a 3-year period (1968-70). Lowest emissions were obtained with a precombustion-chamber engine. Emissions from the 2-cycle, direct-injection engine fell within the range of emission rates for the 4-cycle, naturally aspirated, direct-injection engines. Excluding the precombustion-chamber engine and excepting one of the 4-cycle, naturally aspirated engines, carbon monoxide emission rates were about the same for all engines tested. Test data on smoke, odor, and emissions of hydrocarbons, oxides of nitro-gen, carbon monoxide, and aldehydes are given.

Jan 1, 1971

By D. Bienstock, R. C. Kurtzrock, E. R. Bauer, J. H. Field

To remove hydrocarbons and carbon monoxide in automotive exhaust by oxidation , a catalyst of 4.2 percent Uз Og , 1.7 percent Cr₂ 0 , and 1.7 percent CuO supported on 1 /8 - inch y- alumina spheres was tested in a reactor in place of the muffler of a 1 / 2 - ton truck . Tests were made with both nonleaded and leaded gasolines . With the engine at operating temperature , tests were made with the engine idling and with the vehicle cruising at 30 mph . Auxiliary air was added to maintain an oxygen concentration of 3 to 4 percent in the gas leaving the catalytic reactor . The vehicle was operated for 83 hours (about 60 percent of the time with the engine idling ) and 525 miles with nonleaded gasoline . Conversions of 98 percent of the hydrocarbons and 100 percent of the carbon monoxide were achieved with the engine idling and with 7,000 ppm carbon atoms and 4- percent carbon monoxide in the feed to the reactor . Hydrocarbon conversions of 75 percent were obtained at cruising speeds of 30 mph with a feed of 1,700 ppm carbon atoms ; the carbon monoxide concentration was less than 0.3 percent in the feed and was unchanged in passage through the reactor . Identical activity was obtained initially in switching to a gasoline containing 1.9 ml tetraethyl lead (TEL) per gallon . However, there was a gradual loss in activity thereafter . Conversions in tests with the engine idling about 50 percent of the time , had decreased by 23 percent for the hydrocarbons and by 25 percent for the carbon monoxide from their initial values after 122 hours and 1,300 miles of operation with leaded gasoline . The levels of radioactive materials in the exhaust of the reactor and the radiation in the vehicle were negligible .

Jan 1, 1963

By L. C. IlsLey, E. J. Gleim

Electrical apparatus because of its flexibility and its adaptability to all classes of service has become essential to the mining industry. Hence the problem of providing electrical equipment that is safe for use in explosive mixtures of methane and air is of prime importance in coal mining. Ilwestigatorsand experiment stations early recognized this fact and much work has been done in the investigation and the development of electrical apparatus for use in atmospheres containing fire damp. The term "fire damp" as applied throughout this bulletin means an explosive mixture of methane and air. Direct-current motors and alternating-current motors of the slipring type when running usually give off electric arcs or flashes that will ignite fire damp. Other 'motors that ha,'e no moving electric contacts may become dangerous through accident, deterioration, or neglect. Auxiliary apparatus such as fuses, switches, rheostats, and controllers may arc, flash, or become heated to snch a degree that fire damp can be ignited. Such equipment is still more dangerous when worn or out of repair. In the United States the development of apparatus for use in gaseous mines has been associated largely with coal-cutting equipment run by electricity. This is undoubtedly due to the use of such equipment at the face of the mine workings, where the chance of igniting fire damp is necessarily greatest. One American manufacturer built a coal-cutting equipment of the totally inclosed type for use in firo damp atmospheres in 1903. Another built similar equipment with special protective devices in 1906, for export. During the years 1910 and 1911, the Bureau of Mines at its Pittsburgh experiment station conducted a preliminary investigation of the safety of such protection as was then in use or under consideration. Five motors were submitted for this investigation, each having somewhat different methods of protection. The results of this investigation were published in Bulletin No. 4G.a

Jan 1, 1920

By Wilson Blake

This report presents the results of a 7-year Bureau of Mines program to review, revise, and make an effective engineering tool of the microseismic method of determining the stability of rock structures. The program consisted of developing new microseismic equipment and data analysis techniques and extensive field investigations to demonstrate the effectiveness and potential of the broad-band microseismic method. The guidelines for choosing the components of a microseismic system are presented along with approximate cost figures. Different microseismic systems are discussed, including completely automated systems. Procedures for conducting microseismic investigations and analyzing microseismic data are discussed in detail. Field situations which show the full value of the microseismic technique as an engineering tool are described.

Jan 1, 1974

By J. W. Town

Studies were made by the Bureau of Mines to determine the influence of textural features on the beneficiation of phosphate minerals (pellets) from selected bed and composite samples representing different rock types of the Western Phosphoria Formation. The particle size of the samples was reduced by attrition grinding to minus 20-, 28-, or 48-mesh depending on ore grade and gangue matrix. Sizing of the ground material showed that the phosphate pellets would concentrate in the plus 200-, 270-, or 325-mesh size fractions sufficiently so that the phosphate content was above the 31.5 :cent P2O5 required for acidulation. The phosphate content of essentially pure phosphate pellets was shown to range from 33 to 39 percent P2O5. Microscopic identification of the particles in each size fraction showed that the phosphate was either in the pellet form and readily liberated or so intimately associated with the gangue matrix that size reduction necessary Co obtain liberation was impractical.

Jan 1, 1967

By V. E. Homme

Low- and high-temperature reduction techniques were employed by the Bureau of Mines in study of conditions favorable to the formation of massive titanium crystals. '1,1,2 low-temperature method, feeding molten sodium to solidified titanium lower chloride-sodium chloride, produced higher quality and high quantity crystalline metal. The percentage of crystalline titanium was increased with increasing reactor diameter, melt depth, and titanium dichloride concentration. The high-temperature technique, feed molten sodium to melts above 8000 C, producing needle-type crystals of lower quality and with less consistent results than the low-temperature method. Layers of titanium foil, sponge, fine needles, wool, and crusts of sin-tered granules were formed during the earl, -art of the low-temperature reduction, and massive crystals were produced beneath this barrier in the latter part of the reduction. Crystalline titanium having an average hardness of Bhn 76 and representing 58 percent of the total titanium was obtained. Lamellar crystals up to 1 1/2 inches long with a hardness as low as Bhn 54 were also produced. A second-stage reduction for reclaiming titanium from offgrade sponge is described. Titanium produced by this method was comparable in quality to that from sodium reduction of titanium tetrachloride.

Jan 1, 1966

By Erik Bengtsson

Phenol was discovered in coal tar by Runge (1)1/ in 1834 and was isolated (2) in 1841 as pure phenol by distilling the tar, extracting with caustic soda, acidifying the extract, and fractionating the tar acids. Later, o-cresol was isolated (3) through careful fractional distillation of the tar-acid mixture. The m-and p-cresols distilled within a boiling range of about 1.50 c. and had to be separated by other means. Raschig (4) fractionated the tar-acid mixture to obtain pure o-cresol, sulfonated the mixture of m-and p-cresols, and treated the cresol-sulfonic acids with superheated steam at 1200 to 1300 c. to hydrolyze the m-cresol sulfonic acid, the p-isomer was not affected at that temperature. He also attempted to make use of the different crystallizabilities of the m-and p-cresol sulfonic acids (5). When treated with sodium bisulfate and sodium pyro-sulfate at 100° to 110° C. or with sulfuric acid (90/0) at 20° C., only the m-cresol was sulfonated (6). Hoffman-La Roche (7) treated the meta-para mixture with concentrated sulfuric acid at 40° to 100° C., when m-cresol and part of the p-cresol was sulfonated, and precipitated the m-cresol sulfonic add by diluting with water. The same sort of separation may be carried out by means of 80 percent sulfuric acid at 35° C. and 35 mm pressure (8).

Jan 1, 1950

By Robert K. Koch, Henry E. Blake

Laboratory tests were made to determine if aluminum fluoride of commercial grade could be synthesized by reacting alumina hydrate with dilute ( 25 to 75 grams per liter of fluorine ) aqueous fluoride solutions . • Products containing up to 90 percent aluminum fluoride ( A1F ) were synthesized by reaction of alumina trihydrate ( A120 3H2O) with either dilute hydrofluoric acid ( HF ) or ammonium fluoride ( NHF) solutions , the ammonium fluoride solution resulting from ammonia ( NH ) desilication of a hydrofluoricfluosilicic acid ( HF - H₂ SiF ) solution . Fluorine recoveries of over 80 percent were obtained with either type of solution . The hydrated precipitates of AlF, and ( NH4 ) , A1F ( ammonium aluminum fluoride ) obtained by reacting hydrated alumina with these solutions were subsequently converted to anhydrous AlF, by controlled heating .

Jan 1, 1964

By C. C. Furnas

Despite the fact that a great many industrial processes depend on efficient contact between a gas stream and a bed of broken solids for their operation, the data in the literature are very meager. Several investigations3 have been undertaken, but the work has been limited in scope and application. BUREAU OF MINES PROGRAM OF RESEARCH For the past 10 years the United States Bureau of Mines has been engaged in research with the object of formulating a more or less complete quantitative theory of the workings of the iron blast furnace. Obviously, in order to do this one of the essentials is to have considerable definite information on the laws of gas flow through beds of broken solids. This report in a brief summary of the experimental work on the problem which has been done at the North Central Experiment Station. The complete report with more detailed tabulation of the data and explanations of the experimental procedure is in process of publication in the form of a bulletin.

Jan 1, 1928