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By Timothy J. Rohrbacher

This report presents a U.S. Bureau of Mines study that incorporates coal mining factors, coal recovery factors, and economic factors into the definition of an economically recoverable coal resource. The relationship between these factors to the Energy Information Administration's estimate of U.S. coal resources-the "Demonstrated Reserve Base"-is discussed. The Matewan 7-1/2 minute quadrangle in eastern Kentucky was selected as the initial study area. Results indicate that of the original 1,193 million tons of resource in the quadrangle, only 89 million tons (7.5%) are economically recoverable at a cost of $25 per ton or less. At the current production rate of 5.3 million tons per year, this represents only 16.8 years of remaining reserves.

Jan 1, 1993

By W. A. Cole

As the mines get older and the active workings get Farther and farther away from the original mine openings, it becomes increasingly difficult and expensive to ventilate most coal-mines properly. At the same time, the avenues of escape for those employed underground have become so extended' as often to make it impossible for them to make their way out of the mine in the event of a fire, mine explosion, or other emergency. Where such Conditions exist, the only satisfactory solution is to make new ventilation and emergency-escape openings near the active mine workings. At most mines this would necessitate sinking shafts, which is often slow and expensive.

Jan 1, 1945

By BUREAU OF MINES

LIST OF PUBLICATIONS ON CERAMIC INVESTIGATIONS U.S. BUREAT OF MINES .

Jan 1, 1923

By Philip W. Holland

The U.S. Bureau of Mines has developed an improved method for determining dissolved helium in water in the concentration range of 4.0 x 10-8 to 270 X 10-8 cm3 He (STP)/cm3 H2O. The method is a modification of a previously reported method that was developed for analrzing surface and subsurface waters in geochemical survey work. Water samples are collected in SOD-cm stainless steel cylinders, and the dissolved gases in a sample are extracted into an evacuated cylinder of equal volume. After addition of 30 psig of nitrogen containing less than 2 ppb helium to the extracted gases, the resulting mixture is analyzed for helium using a helium-tuned mass spectrometer. The helium content of the water sample is determined from an empirical calibration that is established by analyzing standard solutions of helium in water. The accuracy of the method is ±7 pct for helium-in-water concentrations above 10 x 10-8 cm3 He (STP)/cm3 H2O.

Jan 1, 1989

By R. V. Ramani, R. Stefanko, G. W. Luxbacher

Le Système International d'Unités (SI) Equivalents of Common United States Units Length 1 ft (foot) = 0.30480 m Mass 1 lbm (pound mass) = 0.45359 kg Force 1 lb (pound) = 4.4482 N Volume Flow Rate 1 cfm = 0.00047195 m3/s Mass Flow Rate 1 lbm/min = 0.00756 kg/s Pressure (wg at 20° C) 1 inch wg (water gage) = 248.36 N/m2 1 inch wg = 248.36 Pa Power 1 hp (horsepower) = 0.74570 kW Energy 1 ft-lb = 1.3558 J Torque 1 lb-inch = 0.11298 N-m

Jan 1, 1977

By Robert F. Randolph

Research on improving haulage truck safety, started by the U.S. Bureau of Mines, is being continued by its successors. This paper reports the orientation of the renewed research efforts, beginning with an update on accident data analysis, the role of multiple causes in these accidents, and the search for practical methods for addressing the most important causes. Fatal haulage accidents most often involve loss of control or collisions caused by a variety of factors. Lost-time injuries most often involve sprains or strains to the back or multiple body areas, which can often be attributed to rough roads and the shocks of loading and unloading. Research to reduce these accidents includes improved warning systems, shock isolation for drivers, encouraging seatbelt usage, and general improvements to system and task design.

Jan 1, 2000

By M. D. Schlesinger

As part of the development of processes for producing synthetic fuels from coal, the Bureau of Mines prepared a special jet fuel in a pilot plant for evaluation by the Air Force. This jet fuel had all the required physical properties, including the important specifications of high heating value and high density. However, the finished fuel did not pass the stability test specified by the Air Force and conducted by the Southwest Research Institute in a high-temperature research coker. The cause for this instability is being investigated because pure compounds of the type identified in this fuel are known to be stable. The tar acid oil used was a 230° to 300° C. fraction of low-temperature tar obtained by carbonization of a West Virginia bituminous coal in the pilot plant of the Consolidation Coal Co. Both the desulfurization at 400° C. and saturation at 300" C. were done in the vapor phase at 2,500 p.s.i.g. After catalytic treatment and distillation the final jet fuel had a boiling range of 194° to 247° C., a net heating value of 18,420 B.t.u./lb. and a specific gravity of 0.8463 60° F./60° F. It also had u pour point below -62° C., and at 0° C. its viscosity was 4.5 cs. The oil was virtually all bicyclic, 41 pct. noncondensed and 56 pct. condensed.

Jan 1, 1961

By J. E. Matta

The Bureau of Mines has developed a tracer gas method for measuring leak-age through permanent mine stoppings. In this method, a temporary brattice is erected in the same entry as the leaking permanent stopping. Leakage was evaluated from concentration measurements of a tracer gas introduced into the space between the stopping and brattice. Stopping leakages ranging from 15 cfm to 265 cfm were simulated in an underground coal mine. Leakage values determined by the new method were within 10 pct of the known values.

Jan 1, 1978

By P. D. Bergman

The high price of pollucite ore, its limited availability, and the need to provide stack removal of S02 present formidable obstacles to the use of pure cesium as a seeding material in MHD power generation. Cost estimates indicate that mixed potassium-cesium seeding is preferable to the use of either pure cesium or pure potassium. Cheaper electricity and higher open-cycle MHD operating efficiencies result from the use of mixed seed. Savings of $3,000,000 per year in power costs for a 1,000-MWE open-cycle MHD power-plant are envisioned if the mixed seeding technique is adopted.

Jan 1, 1972

By H. R. Babitzke

The purpose of this investigation was to evaluate the potential of columbium-hafnium alloys as structural materials for use at elevated temperatures. The work described in this report was conducted to determine the properties of columbium-hafnium alloys and to select the more promising ones for further improvement. Properties determined in this report were machinability, hardness, workability, tensile strength, and oxidation resistance. Ten ingots, ranging from 100 percent columbium to 70 atomic-percent hafnium, were prepared and subjected to tests. The test results showed that the alloys with 33 and 50 atomic-percent hafnium were superior in workability, strength, and oxidation resistance. For the alloy series tested, the strength and hardness values increased with the increasing hafnium content. Maximum values were reached with 50 atomic-percent hafnium. The oxidation resistance was poorest at the 1 atomic-percent hafnium level but improved with increasing hafnium content through 70 atomic-percent. Eight of the ten ingots were fabricable at room temperature. The two remaining ingots, those with 5 and 10 atomic-percent hafnium, required hot-working.

Jan 1, 1962

By Charles D. Litton

Laboratory experiments were conducted to determine the responses of a prototype smoke detector and a commercially available photoelectric smoke detector to smoke particles generated from various combustion sources. The prototype smoke detector combines optical scattering measurements with ionization chamber measurements in order to reduce/eliminate nuisance alarms due to the presence of airborne dusts or diesel exhaust particles. The commercially available smoke detector is designed for use in harsh environments where airborne dust represents a major problem due to both nuisance alarms and detector contamination. In the experiments, the responses of the two detectors were measured when exposed to smoke particles from the exhaust of a diesel engine and from a variety of fire sources, including wood, coal, styrene butadiene rubber, and No. 2 diesel fuel. For the solid fuels, data were obtained for both smoldering and flaming combustions. This report describes the experiments, their results, and the use of these results as they apply to early-warning fire sensors capable of the rapid and reliable detection of fires in atmospheres that may or may not be contaminated by either airborne dust or the products produced from diesel engines.

Jan 1, 2008

By R. V. Ramani, K. V. K. Prasad

"Solution of most engineering problems requires, in addition to vast ·numerical calculations, substantial use of practical judgement and expertise. With advances in applied mathematics and computer technology, the numerical aspects of problem solution have reached a considerable level of maturity; However; it is only .recently that approaches like the expert systems methodology have been developed to ·incorporate the Judgemental aspects as well. For rapid development and prototying of expert systems, expert system building tools or ""shells"" have become widely available. For the expert system developer, identification of the key characteristics of the problem domain and selection of the right expert system tool are of crucial importance. In this paper, the important attributes required in an expert system shell for use in the development or a mine ventilation planning expert system are discussed. These attributes are general in that most engineering problems in mining would have these requirements. Also, the results of an exercise undertaken to evaluate commercially available shells for application to mining engineering problems are presented.INRODUCTIONExpert systems (ES) are interactive computer programs which use high quality specialized knowledge in some narrow problem domain to solve complex problems in that domain. These complex problems lack structured and/or standard ways of solution and involve substantial use of subjective and experience based knowledge. One of the first expert systems was MYCIN, developed in 1974, in which subjective and heuristic knowledge of expert physicians was used to diagnose infectious diseases and provide antimicrobial therapy (Buchanan arid Shortliffe, 1984). Since MYCIN, expert systems applications have appeared in other areas such as mineral prospecting (Gaschnig, 1982), configuration of computers (McDermott, 1982) and structural engineering (Bennett and Englemore, 1979)."

Jan 1, 1989

By Robert L. Chufo

The paper, "An Electromagnetic Roof and Rib Thickness Sensor" presented at The 12th WVU International Mining Electrotechnology Conference in 1992, presented the results of roof coal thickness measurements in underground mines and rib coal thickness measurements in highwall mines. The microwave sensor described uses a unique spatial modulation scheme created by antenna motion, along with frequency domain signal processing, to solve the problem of media, target, and antenna dispersion. This paper further describes the advantages of the unique frequency domain signal processing technology chosen by the U.S. Bureau of Mines in extending previously reported one-dimensional thickness measurement technology to the generation of a full three-dimensional underground image of the underground environment. The electromagnetic signature of a media, whether it is coal or other geological material, is its permeability and permittivity and the effect on the velocity and amplitude of an electromagnetic wave as it passes through. High-quality imaging cannot occur without the identification of, and correction for, the permittivity and permeability of each layer of a multilayer geological deposit. Clutter, or any signal that can interfere with target discrimination, usually comes from objects in the field of view for which there is no design control. These are nuisance targets with possibly very high contrasts compared to the real target. The only proven tool to reduce clutter is to increase spatial, spectral, and polarization diversity. This paper will describe some techniques being used by the U.S. Bureau of Mines to increase the information content of both single-dimensional and three-dimensional imaging systems through the identification of media distortion mechanisms made possible by the use of spatial/spectral sensor technology. These techniques will permit high quality imaging in an environment where the data is corrupted by dispersion and clutter.

By Scott Turner

We have gathered here in Pittsburgh, at the Nineteenth Annual Safety Congress, in order to advance the cause of safety. Although my personal inter- est in this movement alone would have been sufficient to insure my presence here, specific duties have brought me to this congress in an official capacity. My responsibilities as the head of the United States Bureau of Mines, which makes the promotion of safety in the mining and allied industries one of its major activities, necessitate my attendance. My obligations as president of the Joseph A. Holmes Safety Association, an organization closely allied to the bureau and which has for one of its objects the public recognition and reward of outstanding achievements in safety, require that I be present at this time. This morning, my job is to present the Holmes safety certificate to the Lehigh Portland Cement Co. First I will remind you of the nature of this safety association, named in honor of the first director of the Bureau of Mines. After Mr. Holmes' death, in 1915, a number of influential organizations banded together to commemorate the name of this leader in the conservation of human life. In order that you may appreciate the significance of an award by the Joseph A. Holmes Safety Association, I shall read you the list of 24 national organizations which comprise its membership:

Nov 1, 1930

By Richard A. Andre, R. Larry Grayson, Thomas Simonyi

"INTRODCICTIONThe search for the cause(s) of coal workers' Pneunoconiosis continues despite the vast amount of research that has been undertaken over the past forty to fifty years. Good correlation between the mass of dust inhaled over workers' lifetimes and the incidence of the disease has led to the development of effective environmental standards and implementation of good procedures for the control of dust generation and dispersion in the working place. Research has only begun, however, to uncover the biochemical mechanisms involved in initiating the disease.Correlation between the rank of the coal seam in which miners worked and disease incidence and severity is acknowledged worldwide, but the agents in the higher rank coal seams which cause CWP arc still not defined. The basic components of the coal seams, i.e., the elements and minerals, are generally known, but the way in which they interact with human pulmonary cells is largely still a mystery.The process of disease development is a biochemical one which depends on the characteristics of the pulmonary cells within their immediate biochemical environment and the characteristics of invading respirable coal mine dust particles, probably both chemical and physical ones. The cell-particle relationship, therefore, must be defined, and both cells and particles must be characterized according to properties which potentially are involved in the disease process.Following such characterization, specific respirable dusts from different coal seams, which appear to have different effects on coal workers, must be obtained or constructed and then used in experiments designed to determine dust toxicity or the response of animals exposed to the dusts.The results presented here focus on characterizing properties of respirable coal mine dust particles collected from operating longwalls in West Virginia and Virginia Longwall panels were selected for analysis because the respirable dust in the coal face areas is largely uncontaminated by rock dust and analysis of the dust yields results unconfounded by rock dust."

Jan 1, 1990

Improve the health and safety of underground mine workers by finding ways of keeping them away from unsupported areas of the mine. Background Roof falls have been the leading cause of fatal accidents in the underground coal mining industry. During 1985-89, 92 coal miners were killed by falls of roof and rib, with more than 4,000 miners injured. According to accident investigation reports from the Mine Safety and Health Administration, 47% of the victims of these fatal roof fall accidents were in the area of unsupported roof al the time they were killed. There is an urgent need to find out why miners go under unsupported roof and to devise strategies for preventing this unsafe behavior. Approach To discover what can be done to prevent miners from going under unsupported roof, confidential interviews were conducted with 297 miners who work in the face crews of 6 different coal mines. The interview topics included company policies and actions regarding going under unsupported roof, how foremen react to people who go under unsupported roof, circumstances likely to cause some people to go under unsupported roof and how to prevent these situations, and observations concerning those who go under unsupported root.

Jan 1, 1991

By John T. Aydelotte, Martin J. Gavin

" Oil shale contains little or no oil as such , but it contains an organic material from which oil may be produced by destructive distillation" . This statement , or others conveying the same meaning, appears in many popular and techni cal articles on oil shale . It is based on the belief that the ordinary solvents of petroleum have but little action on the organic substances contained in oil- yielding shales , although on distillation these same shales may yield upwards of 50 gallons of crude shale oil per ton . A 50 - gallon shale thus yields by distillation 18.73 per cent of its weight as oil ( assuming the specific gravity of the oil to be 0.900 ) , although only a relatively small part of this can be recovered by extraction with such solvents as chloroform , carbon tetrachloride , and the like . In the course of certain experiments designed to determine the solubilities of different shales after they had begun to yield oil by distillation , it was found desirable to determine the quantity dissolved from certain unheated shales by various solvents , at or near the boiling points of these solvents . The method used and results obtained are presented below. These experiments were made in connection with the oil - shale investigations being conducted by the U. S. Bureau of Mines , in cooperation with the States of Colorado and Utah .

Jan 1, 1922

By Travis Rhoden

Merriam Webster?s Collegiate Dictio­nary (1996) defines team as ?a number of persons associated together in work or activity? and teamwork as ?work done by several associates with each doing a part, but all subordinating personal prominence to the efficiency of the whole? (page 1209). According to Dr. Geller, author of Building Successful Safety Teams: Together Everyone Achieves More (1998), a team of people working together for industrial safety consists of as few as two people or as many as fifteen who have complementary skills, assignments, or abilities for completing a particular task. Effective teams have members who share a common mission and relevant goals, and they share specific methods to reach their goals and accomplish their mission. They also have an evaluation system in place for holding themselves mutually accountable for goal-directed responsibilities.

Nov 1, 1998

By Oliver Bowles

"A Product from Mica Mines.Mica commonly occurs in pegmatites which consist of large crystals of feldspar and quartz, mica constituting but a small proportion of the total rockMuch of the feldspar thus thro n out during the process of mining is pure and of high quality, end the Bureau of Mines has suggested that much of it could be utilized for ceramic purposes. Encouragement is given to such utilization by the fact that several mines now worked for mica were formerly operated for the production of feldspar. ""'here mines are not readily accessible to railroads feldspar utilization might not be feasible, for it is a much lower priced product than mica and cannot therefore bear as heavy transportation expense. '""here mines ire located close to railroads, however, such utilization would tend to reduce the cost of mica mining, and at the same time assist in the solution of the waste disposal problem.The Bureau has recently been informed that some of the feldspar from mica mines near Spruce Pine, N.C., is now being sold and shipped away. An extension of this by-product industry is to be recommended.A Mica Deposit in New York City.The Bureau recently received a mica specimen obtained from a. building excavation at 157th St. and Riverside Drive, New York City. The specimen was about 2 by 4 inches in size, and fairly clear though containing numerous hair cracks. It was obtained only 7 or 8 feet below street level. At greater depth and with more careful methods of excavation material of much better quality might be obtained. The material submitted could be used for mica washers but not for sheet mica. It is stated by an official of a prominent mica company that many such fragments are obtainable in this locality and the possibility of the occurrence of a good mica vein is thereby suggested."

Jun 1, 1920

By William C. McBee

Prompted by forecasts of a sulfur oversupply, the Bureau of Mines, U.S. Department of the Interior, is conducting research on potentially large-scale uses of this commodity to extend or replace such construction materials as asphalt, cement, and mineral aggregates. Through these efforts, paving materials have been developed in which sulfur replaces up to 50 pct of the asphalt normally present and which can be prepared and placed with existing mixing and paving equipment. Laboratory properties and design methods for this direct mixing process are described along with properties obtained on small-and large-scale field demonstration projects. These properties are compared with those obtained from control materials prepared without sulfur additions. Monitoring for toxic gases during laboratory and commercial mixing and paving operations is discussed also.

Jan 1, 1978