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By Roger M. Turpening

This study was performed to examine the feasibility of using seismic shear waves to detect the presence of abandoned coal mines. !he Antiquity Coal Mine near Antiquity, Ohio was used as a region of known voids. No attempt was made here to accurately locate the mine tunnels if detection was obtained. The results of this study were positive. Sharp changes in the amplitude of the received shear waves were clear indications of the presence of a fluid (gas or liquid) filled region between the source and receivers. When moving the source showed no change in the received signals it was concluded that the voids existed beneath the sensors. Prior to these tests drilling (SM-3) had determined that a void did exist in this area. This void was confirmed by this shear wave test and two additional voids were found.

Jan 1, 2012

A symposium on the health hazards of respirable dust in the mining and milling of talc was held on May 8, 1973, in Washington, D.C. The results of medical effects on both human and animal subjects were presented. Methods for identification and classification of talc minerals were also presented. Analytical techniques discussed included X-ray diffraction, scanning electron microscope observation, electron probe, and optical microscopy.

Jan 1, 1974

By James H. Aase

Shales from 10 locations in Michigan were sampled, tested, and evaluated to determine their suitability as raw materials for producing lightweight aggregate by rotary-kiln methods. Sampling procedures and the geology of the shale units tested are discussed. Preliminary testing in a muffle furnace preceded extensive testing in a l6-inch by 14-foot rotary-kiln. Rotary-kiln products from these shales ranged in weight from 35.5 to 61.2 pounds per cubic foot (pcf). Concrete test specimens made pith selected aggregates were evaluated to determine the qualities of the concrete. Compressive strengths of the concrete ranged from 2,830 to 4,240 psi after 28 days of curing. Unit weight of the concrete ranged from 94.8 to 101.5 pcf. Lightweight aggregate suitable for use in structural concrete meeting ASTM standards was produced by the rotary-kiln method using shale samples from two locations.

Jan 1, 1967

By John B. Gayle

The Bureau of Mines has designed and constructed an experimental coke oven, using a commercial oven as a model where practicable. Because the rate of carbonization is important in determining the quality of the coke produced and may affect the "mount of pressure developed during carbonization, particular attention was given to those elements of the design that govern the heat transfer to the charge. The new oven deviates in design from most existing test ovens in that the charge is full width (17 inches), the heating walls ore constructed of 4-1/2-inch silica brick, and zoned, heat-input arrangements compensate for heat losses at the ends, top, and bottom of the charge. This report describes the oven, which was designed by H. S. Auvil and installed under his direction, at the Southern Experiment Station, Tuscaloosa, Ala., while he was supervising, engineer, Coke Section. It gives the results of a limited number of carbonizing tests. These results indicate that the main objective in designing and building this oven, that off duplicating commerical, slot-oven carbonizing conditions, has been accomplished; if coke-discharge conditions simulate commercial-oven conditions, the cokes from the experimental oven arc very similar to oven coke, in soma tests being fully as close is duplicate tests from a Angle batch of coke.

Jan 1, 1952

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

Reduce the number of accidents in which large mining trucks crush objects that were not visible to the driver. Approach Improved rear view mirrors, light-bending plastic lenses, and a closed circuit TV, are combined in a rugged system that allows the driver to see almost all areas around a large raining truck. How It Works Improved mirrors, used in place of ordinary left and right rear view mirrors, give wider angle viewing. Fresnel lenses, two mounted on the front edge of the hood and another one mounted above the right front fender, show objects close to the front and right side of the truck. A rugged closed circuit TV camera mounted above the rear axle reveals objects behind the truck. See diagrams showing reduction of blind area around a 150-ton mining truck. The improved mirrors for rear viewing are approximately rectangular. The left rear view mirror has a flat reflecting surface 10 inches wide by 20 inches high. The right rear view mirror is curved to give wider viewing angles, both from left to right and up and down. This mirror is 12 inches wide by 16 inches high. Its convex reflecting surface has the same curve as the surface

Jan 1, 1979

By Louis Schaffer

The purposes of the research were to assess the applicability of new accident investigation methods to mining accidents, and to adapt those found to be applicable in the development of a new methodology for use in mining. The development included field testing, evaluation and modification of the new methodology. The report is in two volumes. Volume one discusses the background research, the design of a methodology for field evaluation, preliminary field tests in Utah mines, and work done to prepare for a formal, complete evaluation by federal government mine safety officials. This, volume 2, discusses the field evaluation done by the contractor and cooperating mines after the program was re-directed by the Bureau of Mines. It relates to research done during a period of approximately eighteen months, ending in April, 1983.

Jan 1, 1986

By Terry S. Cory

This report describes the results of a measurement program to determine the broad spectral characteristics of both differential and common mode noise on phone lines in three coal mines; and, signal attenuation spectral characteristics on the same broad basis over phone line strings with taps/branches. The frequency range used was baseband -1000 Hz for resolution bandwidth ranging from 100 Hz near baseband to 30 KHz near I MHz. The signal attenuation measurements were performed on all three "legs" of taps where possible and applicable. Results were obtained comparing shielded and unshielded phone lines In one mine. The results include an improved electromagnetic noise chart for coal mines showing variations with types of mines, topology, and location of noise sources; also, fundamental high-frequency limit on untreated phone lines in coal mines is identified

Jan 1, 1981

By Frank G. Horino

This report presents a method of utilizing the Coulomb strength criteria for estimating the strength and stability of pillars and pit slopes containing planes of weakness. It is assumed that the Coulomb theory, as a special case of the Mohr envelope, is a satisfactory first approximation of failure in uniaxial compression or triaxial loading with low lateral loads. Accepting this assumption for brittle materials, an expression for the strength decrease of rock pillars containing a plane of weakness or fracture at any angle of orientation is derived. As few as six samples (three solid cores and three fractured cores at a failure-oriented angle) are required for testing uniaxially and triaxially to statistically determine the coefficients of friction and the shear strengths of both the solid rock and the fracture plane and the range of failure angles of the fracture plane. Interpretation of the data shows that the mean normal stress and maximum shear stress technique of analyzing the data is superior for solid core and that shear and normal stress values using angles of failure should be used for fractured specimens with failure-oriented angles. Plots of either the strength or strength ratios against fracture angles obtained from oriented drill core samples give a useful first approximation of strength decrease due to fracture. Using the same test conditions for both fractured and unfractured material increases the validity of the tests.

Jan 1, 1970

By Anderson Dana

THIS PAPER describing methods and costs of mining and preparing gravel and sand for market at the Port Jefferson plant of the Seaboard Sand and Gravel Corporation, is one of a series of articles on gravel and sand mining, prepared for and published by the U. S. Bureau of Mines, which is designed to disseminate technical information regarding the methods used. The cost tabulations represent operating expenditures only and not total costs, It is recognized that publication of total costs might in many instances cause embarrassment to individual producers, as well as to the industry as a whole. On the other hand, operating costs are essential to the technical [ ]

Jan 1, 1932

By Rupert O. Yantz

This report, authorized under contract Number H0111403 Amendment Number One, entitled, "Exploration of Illumination Concepts for Underground Coal Mines", contains the results of an investigation of methods, procedures, and technology for providing working place lighting in underground coal mines and construction of a prototype, man portable, mine illumination system and a prototype, machine mounted, mine illumination system for use in high and low coal entries of underground coal mines.

Jan 1, 1972

By M. R. Yenchek

The U.S. Bureau of Mines designed and constructed sensitive and coordination-free ground-fault relays (GFR's) for use on mine power systems. First, a list of GFR attributes for mine ac utilization applications was compiled. These practical guidelines specified design, construction, transient immunity, reliability, and operating criteria. The time-current characteristics of the ac and dc units, subsequently fabricated, were designed to be below the human electrocution threshold. The significant and highly variable capacitance of high-voltage distribution cables was found to preclude the sensing of ground currents in the milliampere range. However, the coordination-free system developed for high-voltage distribution should enhance safety by significantly decreasing response time to ground faults. Implementation of the sensitive GFR technology in the mining industry has the potential to eliminate the majority of injuries and nearly all the deaths resulting from contact with energized components.

Jan 1, 1990

An active list of permissible explosives was published in July, 1931, as part of United States Bureau of Mines Report of Investigations 313, under the title of "Active List of Permissible Explosives and Blasting Devices Approved Prior to June 30, 1931." Changes in that list were authorized in August, September, October, November, and December, 1931, and. January and March, 1932, as published in Reports of Investigations 3l40, 3147, 3l50, 3155, 3158, 3161, and 3163, respectively. By these changes the following explosives were added to the active permissible list: [Austin Red Diamond No. 1, L. F. Gel-Coalite W. L. F. Austin Red-Diamond No. 5, L., F. Gen-Gel No. 2. Black Diamond Nu-Gel No. 1 Genite C-1 Burton 1, L. F. Liberty No. 4 Burton 2, L. F. Liberty No. 5 Burton 10, L. F. Peerless D Burton 12, L. F. Permigel 1, L. F. Burton F, L. F.]

Jan 1, 1932

By H. H. Schrenk, Carlton E. Brown

"The purpose of this paper are (1) to present a broad picture of the recognized methods of measuring the various forms of atmospheric pollution; (2) to evaluate the significance of such measurements; and (3) to suggest suitable methods for obtaining comparative information on the concentration of contaminants in city air.The atmosphere (the gaseous envelope surrounding the earth) consists of a mixture of gases. These gases and their usual proportions are:4/The volume of water vapor in the atmosphere ranges from almost zero (in very cold weather) to about 5 percent arid averages about 1.2 percent.Strictly speaking, any other substance in the atmosphere or an excess of any of the substances mentioned (with the possible exception of water) is a contaminant. Needless to say, there are many contaminants in the atmosphere.In accordance with their physical state, contaminants may be classified as gaseous or particulate, and the latter may be classified as solid or liquid matter. Particulate matter, especially when dispersed in some medium such as air or some other gas, sometimes is referred to as dispersoid, and the complete system of gas and dispersoid is referred to as aerosol.All substances on the earth are potential sources of atmospheric contaminants. Combustible materials (particularly fuel for heating and power), sea water, earth or soil, metals, and animals (including man) are some of the important sources of contaminants.Ordinarily gases are produced by chemical processes, whereas dispersoids are produced by both chemical and physical processes. There are two general dispersoid-producing processes: (1) Condensation, in which molecules join to form larger units or particles, and (2) disintegration, in which large units are reduced to the particulate range (which for the purpose of this article may be considered to be from 100 microns, or 1/254 inch, down to molecular size) by such processes as crushing, grinding, abrading, and atomizing.“Condensoid"" is a convenient term for dispersoids formed by condensation, and ""disintegrasoid"" for those formed by disintegration. Solid condensoids are sometimes called ""fume,"" solid disintegrasoids ""dust,"" liquid condensoids ""fog,"" and liquid disintegrasoids ""mist.""5/"

May 1, 1942

By L. C. IlsLey

Cooperation between the United States Bureau of Mines and the Safety in Mines Research Board of Great Britain, continuous since 1924, has made possible this and other papers on safety subjects. Grateful acknowledgment is made to representatives of the Safety in Mines Research Board of the Mines Department for their assistance in arranging visits to several mine-safety stations, and to F. H. Wynne, Deputy Chief Inspector of Mines, Great Britain, for arranging visits to mines in Great Britain, Belgium, France, and Germany. During the summer of 1927 the writer had the privilege of visiting the mine-safety testing stations in Great Britain, Belgium, Germany, and France, in the order named. All of these countries have large coal mines, many of which are rated as gassy. Therefore, when the installation of electrical equipment is contemplated, each of these countries is confronted with the same safety problem as in the United States - the development of electrical equipment that will not ignite gassy mine atmospheres, should such atmospheres through neglect or accident surround the equipment. The means used by those countries in safeguarding gassy mines should therefore be of general interest to safety engineers in American coal mines, and it is proposed to give a brief survey for each of the four countries mentioned. The first of these surveys will cover conditions in Great Britain.

Jan 1, 1929

By H. R. Appell

The Bureau of Mines is experimentally converting cellulose, the chief constituent of organic solid waste, to a low-sulfur oil, All types of cellulosic wastes, including urban refuse, agricultural wastes, sewage sludge, wood, lignin, and bovine manure, have been converted to oil by reaction with carbon monoxide and water at temperatures of 350° to 400° C and pressures near 4,000 psig, and in the presence of various catalysts and solvents, Cellulose conversions of 90 percent and better (corresponding to oil yields of 40 to 50 percent) have been obtained. A continuous reactor for use at maximum conditions up to 500° C and 5,000 psig has been operated successfully, Using sucrose as a feedstock, operation in this system has permitted a simplified and preliminary chemical study of the conversion process. Oil yields of over 30 percent have been obtained with this unit.

Jan 1, 1971

By Raymond L. Lowrie

Coal deposits in the Boulder-Weld County coalfield in Colorado are analyzed in relation to economic factors governing the growth, stability, and competitive potential of the coal industry. Recoverable reserves, estimated to be 571 million tons, are discussed in detail, particularly those in the Erie and Frederick Quadrangles. Geology of the coal measures, quantity and quality of water resources, and chemical and physical properties of the coal are described. Coal production factors, including mining techniques and equipment, labor requirements, transportation facilities and rates, and markets, are considered for coal's position in competition with alternate fuels. Growth of the fuels market, through increasing thermal-electric power generation in the Denver Metropolitan Area, will stimulate coal production in Colorado. Reserves of the contiguous Boulder-Weld coalfield, if mined in a sustained, year-round, high-tonnage operation, could be used to supply much of that fuel demand.

Jan 1, 1966

By Roy T. Sorensen

As part of its mission to maintain an adequate supply of minerals to meet national needs and maximize mineral production from domestic sources, the Bureau of Mines is investigating the recovery of alumina by hydrochloric acid leaching of kaolinitic clay. Most iron impurities are leached from the clay along with the alumina and must be removed before or during crystallization to aluminum chloride hexahydrate. The thermal decomposition step then provides an alumina product of acceptable iron analysis. Miniplant studies of a Bureau-developed solvent extraction technique, using a tertiary amine in kerosene diluent, have demonstrated that the iron content in aluminum chloride leach liquors can be reduced to levels of less than 0.007 wt-pct (7 ppm), expressed as Fe203. Entrained and dissolved organic matter in the purified pregnant leach liquor from the solvent extraction circuit can be reduced to less than 2 ppm by using a fabric-packed coalescer and subsequent activated carbon treatment. Investigators discovered that a steady buildup of zinc accumulated in the solvent phase within the extraction circuit, proportional to the amount of leach liquor treated. The solvent phase zinc analysis increased by 0.01 wt-pct ZnO for each 1,000 gal of pregnant leach liquor purified.

Jan 1, 1981

By R. F. Chaiken

The Bureau of Mines has carried out experimental and theoretical studies with prilled and pulverized ammonium nitrate-fuel oil (AN-FO) mixtures containing varying amounts of fuel oil in an attempt to quantify the effects of stoichiometric composition, nonideal detonation behavior, and expansion volume on the production of CO, NO, and N02 fumes. Experimental fume measurements were obtained in the Bureau's large closed gallery facility (7.2 X 104 liter expansion chamber) and in the standard Crawshaw-Jones apparatus (90--liter expansion shamber) using a prepackaged charge configuration containing about 450 g of explosive.4 The theoretical calculation of toxic fumes was achieved with an equilibrium detonation code called "TIGER,," Contrary to initial expectations, the NOx (= NO + N02) fumes from the large gallery test were found to be in essential agreement with the Crawshaw-Jones results. It was also concluded that (1) "TIGER" calculations offer a good approach to the prediction of toxic fumes; (2) there is a basic problem in extrapolating laboratory measurements of CO fumes to mine conditions--this being due to postdetonation oxidation of CO to CO2; and (3) the detonation velocity decay rate of an explosive is a useful experimental parameter for correlating toxic fumes production with nonideal detonation behavior.

Jan 1, 1974

By A. M. Poston

Introduction of radioactive elements into ore samples and/or pregnant liquors and radiometric tracing thereof have greatly improved control of fusion and extraction studies on beryllium ores and products. Extractive metallurgical research on beryllium, normally guided by the usual laborious analytical methods, is both costly and slow. Recognition of this problem by the Bureau of Mines led to the development and application of radioisotope tracer techniques" as a substitute for chemical analysis at the Salt Lake City Metallurgy Research Center, The result was that much faster progress at significantly lower cost was achieved. This report discusses the problems encountered and resolved in using radioactive tracers and radiometric methods, defines the conditions and techniques for their effective use, and delineates the limitations and flexibility inherent in applying such methods in laboratory-scale beryllium research.

Jan 1, 1962