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From the time of its establishment in 1910, the Federal Bureau of Nines has studied the carbonization of coal, and a considerable part of this effort has been devoted to investigations in the so-called low-temperature carbonization range, 450° to 700° C., in which there is minimum decomposition of primary products and maximum yield of Liquids - a yield two to threefold the amount produced in high-temperature carbonization at 900° to 1,200° C, The solid residue, char, or coke, produced in low-temperature carbonization is 70 to 80 percent of the coal charged and may be used directly as a smokeless fuel or for blending with coals to produce metallurgical coke, Although some thought was given to the use of tar and to the illuminating value of gas derived from lm-temperature carbonization, the main emphasis in early work of the Bureau of Mines was on the preparation of smokeless fuel, especially for home use, For example, a carbonizer was designed and operated for making char and briquets from North Dakota lignite without recovery of by- products; however, the shortage of high-temperature coal-tar products in the United States during World War I had already indicated the potential usefulness of low-temperature tar.

Jan 1, 1959

By William M. Hinton

This report describes the approach, procedures, and results of a program to develop training materials for roof bolter operators. The objective of the program was to design and produce a training sequence which would prepare roof bolter trainees for job performance. Data was collected and analyzed using the general procedures of Instructional Systems Development (ISD). Input data came from a previous roof bolter training analysis program. This data was expanded and structured through a series of ISD steps: objectives hierarchies, media selection, syllabus, lesson specifications, and train¬ing materials development. The resulting program consisted of an ordered sequence of 15 lessons. The media mix for the 15 lessons included lectures, slide-tape lessons, and hands-on instruction using operational roof bolters. Contents of all lessons were reviewed and approved by the Bureau. The key recommendations were to (1) validate the materials and measure relative effectiveness of media formats; (2) survey mines for training resources and conditions - match materials to user capabilities, rather than selection state of the art technology/media; (3) develop job performance aids (JPAs) rather than simulators; (4) create a style/media/JPA development guide for use in future projects of this kind.

Jan 1, 1982

8186. Aquilina, C. Determinazioni relative di gravita eseguite nel 1939 (Relative Determinations of Gravity Made in 1939), Ric. Ingegn, Rome, vol. 10, 1942, pp, 6376. In 1939, the author made a survey of relative gravity in the Mediterranean-basin, 41° 35,5' to 41° 56.3' northern latitude and 0° 10,3' to 0° 28' longitude, referred to Mt. Mario. Ten stations were covered; 25 other stations had been occupied in the vicinity of Rome and in Albanian mountains during previous years. The new measurements revealed gravity anomalies ranging within the following limits: (1) With a free-air reduction, between + 29 and + 120 mgl., average + 60 mgl.; and (2) with a Bouguer reduction, between + 22 and + 87 mgl., average + 41.5 mgl. - V. S.

Jan 1, 1946

By Northcutt Ely

This volume summarizes mining and petroleum legislation in 22 jurisdictions of the Near East and South Asia. Within these jurisdictions, primary attention is given to requirements that must be met in each country for acquisition of rights to permit development of mineral resources. Coverage includes : First, identification of the controlling laws or statutes governing minerals acquisition and reference to the administrative authority; second, analysis of the laws governing mines and quarries and their products; and third, analysis of laws applicable to natural gas, petroleum, and related materials. Where pertinent, sections dealing with historical background or administration have been added. In countries where minerals are subject to control of states or provinces, those areas are considered separately from the central government.

Jan 1, 1972

By Mark S. Sanders

This report presents a summary of the work reported by Sanders and Kelley (1981). A task analytic approach was used to define information requirements and visual features which served as sources of information. Information requirements were prioritized and the location of visual features determined. From this analysis, visual attention locations, containing one or more important visual features, were indentified. The visual attention locations are contained in this report. A procedure was developed for assessing whether operators in existing machines could be expected to see the visual attention locations. The procedure makes use of a Human Eye Reference Measurement Instrument (HERMI) designed for this project and an outside-in photographic procedure for documenting compliance with the recommendations. A sample of continuous miners, shuttle cars & scoops were used to test the procedure. Illustrative results are presented in the report.

Jan 1, 1981

By L. H. Wullstein

Nitrogenase activity (C2H2 reduction) was found to be associated with the following grasses in the field: Agropyron dasystachyum, Agropyron smithii, Aristida purpurea, Oryzopsis hymenoides and Stipa comata. Uptake of fixed nitrogen was also demonstrated for these grasses. Two unidentified nitrogen fixing bacteria were isolated, one from Stipa comata and one from Aristida purpurea. Cynodon dactylon and Agropyron cristatum were successfully inoculated with the unknown isolate obtained from Stipa comata. The inoculated plants exhibited nitrogenase activity (C2 H2 reduction) whereas uninoculated controls gave negative results.

Jan 1, 1982

By James C. Barker

Unverified reports of rare earth element (REE) concentrations in gold placers and radioactive mineral prospects in the Zane Hills were investigated by the U.S. Bureau of Mines as part of the Alaska critical minerals program. REE is reported to occur in dredge concentrates at the Hogatza mine and up to 1.2 pct REE was previously analyzed in alkalic syenite (bostonite) dikes marginal to the pluton. In addition, numerous thorium-rich veins, explored for their uranium content but unevaluated for REE, occur on the western margin of the Zane Hills. The Bureau mapped and sampled all of the reported or suspected REE occurrences. Dredge concentrates contain abundant uranothorianite, a mineral species which incorporates cerium subgroup REE. Bostonite dikes occur in conjunction with a multi-phased zoned alkalic intrusion, however, no significant REE concentrations were found. Thorium-rich veins contain nil to 0.5 pct Y but resource potential is limited by this relatively low grade, the ultimate low tonnage potential, and the lack of uranium as a major economic element. The Zane Hills exhibit attractive exploration targets for uranium deposits, primarily in a sedimentary form. Gold may be found peripheral to the pluton in both placer and lode deposits. Resource potential of REE, however, appears limited to a placer by-product of REE-Zr-Ti that is recoverable only during large scale gold placer mining. Placer exploration of the lower Wheeler and Dakli Creeks is suggested.

Jan 1, 1991

By Arnold O. Tanner

Tables based on 1985 data, which were not available in time for publication of the "1985 Minerals Yearbook," are included in this chapter; corresponding tables for 1986 are not yet available. Raw nonfuel minerals produced in the United States during 1986 had an estimated value of $23.5 billion, an increase of $0.25 billion over the 1985 value. This is the fourth consecutive year that the value has increased, and except for a de- crease in 1982, the value each year has increased since 1971, or 14 out of 15 years. Industrial minerals growth slowed from a 3% increase in value in 1985 to a 1.5% increase in 1986, reflecting the slow growth in the domestic economy. The value of industrial minerals, more than three times larger than the value of metals, easily offset the less than 0.5% decline in the value of metal mine production. Although the decline was small, this decrease makes 1986 the fourth year in the past 6 years in which a drop in the value of metal mining production occurred in the United States. U.S. production continued to lag behind the growing world production. Overall, the estimated raw nonfuel mineral production rose 1% over that of 1985. Domestic mine production of ferrous metals declined as follows, in decreasing order of production: nickel, iron ore, tungsten, and molybdenum. All remaining domestic primary nickel and tungsten mines had closed down by yearend. Nonferrous metals that similarly declined included titanium, rare-earth metals, lead, silver, zinc, and magnesium. For the second consecutive year, aluminum, produced predominantly from imported bauxite, declined in production, while imports reached record-high levels. Somewhat modest gains were made in beryllium and copper. As has been the case for a number of years, gold was a bright spot in the domestic and internation-al metal mining industry. Gold production was spurred on by the increasing usage and development of heapleaching techniques that make lower grade ores, which were previously uneconomical, profitable. Additionally, various mining companies, the U.S. Mint, individual States, and a number of foreign countries began production of gold bullion and commemorative coins. Gold output in the United States increased from 2.43 million troy ounces (revised) in 1985 to about 3.73 million troy ounces in 1986, a dramatic 54% rise.

Jan 1, 1988

By Paul J. Remington

The field data gathered as part of the measurements described in Volumes I and II were re-analyzed in the low frequency regime (.1 Hz to 1 Hz) where motion sickness normally occurs. These data were compared co the international standard ?ISO 2631 Addendum 2: Evaluation of exposure to whole body z-axis vertical vibration in the frequency range 0.1 to 1.0 Hz." For both underground mining machines and surface mining machines the results showed that one would not expect motion sickness to .be a severe problem. New field data were gathered on the vibration reduction performance of various seat designs found on surface coal mining machines. The vibration during normal operation was measured on the seat using the standard seat pad accelerometer package described in the previous two volumes and simultaneously on the floor of the machine at the base of the seat. Preliminary indications are that the so-called high performance seats used for operator vibration reduction do not offer significant improvement over conventional seats.

Jan 1, 1984

By R. Ward Stahl

Fire is still a scourge of the mining industry, although many precautionary measures have been and are being taken to reduce the incidence of fires and to combat them. Generally, the success of fire extinguishment is directly proportional to the speed of attack, and the speed of attack in turn is dependent upon the availability of materials and trained personnel. Preparations for firefighting are frequently neglected because they are considered emergency needs and do not contribute directly to coal production. Fire incites panic--a fact often overlooked--but such chaos can be minimized by training people in the use of equipment and procedures. Heat, smoke, and fumes hamper the approach to a fire; however, a relatively new technique of attacking fires with high-expansion foam may well contribute greatly to firefighting. The foam is transported to a fire and used at a considerable distance, thus permitting the firefighters to work more safely.

Jan 1, 1962

By Patricia R. Devine

This appendix documents the mathematical approach to deriving the components of change presented in this report. The formulation closely follows that contained in Chapter IV of the documentation for the BEA 1977 Input-Output Tables.' The basic elements for the calculations include the "use" matrix (U), the "make" matrix (M), and any of the ten columns of final demand (generically represented by the symbol y). The use matrix contains information about changes in the technological processes of production, while the make matrix describes the nature of secondary product production in each industry. We adhere to BEA conventions in maintaining careful distinctions between commodity output (c) and industry output (x). The industry-by-industry 1-0 tables supplied by NYU for use in this analysis are square matrices, with the number of commodities and the number of industries both equal to 85. The BLS table for 1982 (commodity by industry) was aggregated and adjusted to be consistent with the earlier tables. The three basic steps for estimating components of change proceed as follows for each column of final demand. 1) Calculate the actual change in output of each commodity for each of the four time periods: 1963-72, 1972-77, 1977-82, and 1963-82.

Jan 1, 1988

By J. W. Paul, J. N. Geyer

"GENERAL STATEMENTThe purpose of this report, which is the first of a series of three covering mines in the Fairmont district of West Virginia, is to give the result of a' study conducted in seal mines to ascertain the nature of the safeguards employed to prevent injury to the workmen from falls of roof and coal. In presenting the subject matter, consideration must necessarily be given to factors, features, and conditions such as method of mining, timber regulations and practices, supervision and natural conditions; and, for comparative purposes, a certain amount of statistical matter bearing upon the relation of fatalities and injuries to their causes, tonnage produced, men employed, days worked, and time lost.Those features and practices found to promote safe protection are summarized and suggestions made for such additional safeguards and practices as appear to give greater protection against injury from falls of roof or coal.ACKNOWLEDGMENTSThis study of falls of roof and coal in mines in Harrison County has been conducted by the U. S. Bureau of Mines in cooperation with R. M. Lambie, chief of the Mining Department of the State of West Virginia who assigned L. W. Brown, a district mine inspector, to assist in the field work and in the preparation of individual reports on each mine visited in this study. The writers acknowledge the helpful suggestions and cooperation given by these officials, the latter of whom assisted in the field work and prop red most of these sketches for the individual reports which wore submitted to the operator by the chief of the department. Thin report is a summary of the contents of the individual reports heretofore furnished the individual operator."

Aug 1, 1931

By James C. Fowler

As report covers the installation and testing of a permanent seismic monitor system at the Loveridge Mine in West Virginia. The testing of the system showed several things: 1. Getting the seismic data hack to the central computer in a usable form is possible 2. It is possible to detect small explosions. 3. The use of this system as a auxiliary system to detect hammer blows from miners trapped in the area of one of the geophones is possible.

Jan 1, 1974

By J. B. Rosenbaum

Prolonged laboratory and limited pilot plant tests have shown that the Bureau of Mines buffered S02 -H2S process is capable of removing 95 to 99 percent of the S02 from industrial waste gases. Most of the S02 is converted to elemental sulfur; only about I percent converted to sulfate The process comprises (1) washing the flue gas to remove particulates and S03, (2) absorption of the S02 in citric acid or other carboxylate solution, (3) reaction of the loaded solution with H2S in a closed vessel to precipitate the absorbed S02 as elemental sulfur, and (4) separation of the sulfur from the regenerated solution by oil flotation and melting. Two-thirds of the molten sulfur is converted to H2S for use in the sulfur precipitation step by reacting sulfur vapor with natural gas and steam in the presence of an alumina catalyst. The chemistry and mechanism of the process are described, initial laboratory and pilot plant data are summarized, and second-generation laboratory operation and pilot plant design are reviewed. Preliminary cost estimates are presented for recovering sulfur from copper smelter gas, powerplant flue gas, and Claus plant tail gas.

Jan 1, 1973

By Israel Liebman

The Bureau of Mines conducted an investigation to determine those factors that are significant in affecting the velocity of flames propagating along the boundary separating gaseous fuel and air. In addition the aerodynamic motion of the gases in the vicinity of such interfacial flames was delineated. Parameters in the study included flammable zone thickness, flammable zone concentration of gradient, fuel type, and position of the flame relative to various environmental surfaces. Of all these factors, the flammable zone thickness and burning velocity of the stoichiometric mixture were found to have the most significant effect on the flame speed. Notion of the gases in the vicinity of the interfacial flames was examined by particle track and interferometric techniques. The relative velocity of the interfacial flame with respect to the unburned gas on the central streamline was found to equal the burning velocity of a stoichiometric homogeneous fuel-air mixture. In addition, it was observed that the composition of the lean fuel-air mixture at the boundary of the combustion zone appears to be less than that defined as the fuel's lower flammable limit.

Jan 1, 1968

By Kim B. Shedd

An initial evaluation of the flow of cobalt-containing materials in the United States was prepared. The following aspects of materials flow were included: cobalt released as a result of mining and processing other metals and minerals; scrap generation and subsequent recycling or cobalt recovery; and cobalt losses resulting from the generation of wastes, dissipative uses, and disposal of used products. Where possible, estimates were made to quantify the amount of cobalt lost from the materials flow. More than 2,000 metric tons (mt) of cobalt are released annually from mining and mineral processing in the United States, including 480 mt of cobalt in coal produced in the United States. Metallurgical industries examined in this study have well-established recycling or cobalt recovery practices. The petroleum industry recycles spent catalysts, and some chemical catalysts are also recycled. Losses generated during cobalt chemical and powder processing were estimated at 50 to 80 mt of cobalt annually. Losses from alloy processing and the manufacture of parts and products were estimated to be 360 mt. These industrial losses are greatly outweighed by an estimated 2,780 mt of cobalt' consumed in the United States each year to make products that will ultimately be disposed of.

Jan 1, 1992

By William H. Pomroy

Fire on surface mining equipment is a serious hazard to life and property. The Bureau of Mines, through a program of contract and in-house research, has developed and in-mine demonstrated reasonably priced, reliable automatic fire protection systems to deal with this problem. This report reviews the development and subsequent testing of systems for haulage trucks, front end loaders, coal augers, dozers, drills, and shovels. A variety of fire sensors, extinguishing agents, and control systems arc discussed in the context of mine equipment designs and operating environments

Jan 1, 1980

The principle activities of the Explosives Research Laboratory from July 1, 1961 to June 30, 1962, are described briefly in part 1. Part 2 gives short abstracts of publications that appeared during fiscal year 1962; in general, the research reported in these publications antedates the report period. Part 3 gives the results of an investigation which, although too limited to warrant separate publication, merits presentation in some detail because of current interest in ammonium nitrate-fuel oil compositions.

Jan 1, 1964

By W. G. Pariseau

This Bureau of Mines report is an evaluation of the state of knowledge about gravity flow from bin hoppers, the most commonly used method of handling bulk materials where the force of gravity is used. The requirements for flow to be initiated and to continue, formulas developed experimentally or mathematically from various assumptions to describe the materials flow, and the question of whether or not a material will flow over the entire cross sectional area of the bin hopper according to the flow regime developed are the primary areas discussed. The work of A. W. Jenike, whose pioneering investigations raised bin hop- per design from the trial and error state, is examined in depth and its limitations and assumptions are pointed out. Bin hopper design depends heavily upon prior experience, and suggestions for further studies of bin hopper flow to include the effects of feeders are made.

Jan 1, 1972

By Robert H. Peters

The U.S. Bureau of Mines has prepared this report on strategies for maintaining high job attendance among underground coal miners because high absenteeism is a threat to miners safety and seriously hampers productivity. A substantial number of research studies on the effectiveness of various strategies for reducing absenteeism among the employees of nonmining industries have been reported in the literature. These strategies have aimed at improving job attendance through one or more of the following: (1) improving employment procedures, (2) overcoming problems that adversely affect one's ability to attend work, and (3) increasing miners motivation to attend work. Many of these strategies appear applicable to the mining industry, and are reviewed in the first half of this report. The second half of this report describes how one could develop and implement a program for maintaining high attendance at underground coal mines. The steps include: measuring and evaluating attendance levels; formulating attendance goals and an absenteeism policy; developing and implementing an attendance promotion program; and periodically going through the preceding steps known as recycling.

Jan 1, 1989