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By Ludwig Schmidt

"IntroductionThe evaporation losses of gasoline in the refinery, can be reduced by proper methods of refinery construction and operation. When gasoline evaporates slowly, as when stored in tanks that are not vapor tight, the most volatile part evaporates first, so that the remaining liquid in not only less in volume, but is also lower in quality. In some,evaporation changes the characteristics of the product so much that it must be reblended to meet trade specifications.Refiners are, therefore, greatly interested in the various appliances and methods used to reduce these losses. In the past this interest has been directed largely to storage tanks, probably because evaporation from tanks is more readily observed than losses during other refinery operations. As tests by the Bureau of Mines on evaporation of gasoline from small storage tanks had indicated that the losses during the various stages of refining might be equal to or greater than those of standing storage, a survey was during the spring and early summer months of 1924 in a large number of refineries in the Mid-Continent field. In order to enable the refiner to select the results of those tests that conform most nearly to the conditions that he has to meet, tests were conducted at various stages of refining, as follows: (1) Randown tanks, (2) (agitators), (3) filling tank cars, (4) storage of refined products, and (3) miscellaneous handling. The results are presented in this paper."

Nov 1, 1925

By R. S. Conti

This U.S. Bureau of Mines (USBM) report discusses the results of research conducted in the USBM experimental mine at its Lake Lynn Laboratory to determine the alarm times of smoke and carbon monoxide (CO) sensors, and a point type heat sensor (PTIIS) to slowly developing coal-conveyor belt fires. The tests were conducted at air velocities of 0.44 and 0.97 m/s, The data clearly indicate that smoke sensors provide earlier warning of fire than 10 ppm CO sensors, and that 10 ppm CO sensors provide earlier warning than PTHS, A success rate of 1.0 (indicating detection of every test fire) was obtained for both smoke and C8 sensors. For the PTHS, the success rate was 0.57 at the lower air velocity, decreasing to 0 at the higher air velocity, Data are also presented showing the sequence of fire events and detection events at the two air velocities as a function of time. Results show that early detection and warning of underground mine fires will improve the probability of miners' escape.

Jan 1, 2010

By M. A. Mahtab

This report describes the procedures used by the Bureau of Mines for obtaining attitudes of joints surveyed with a borescope in inclined boreholes. An algorithm for computing the dips and azimuths of the observed joints is presented. The algorithm is used to solve an example problem. A computer program based on the algorithm is listed. It is hoped that the procedures described here will be useful in treating large quantities of data obtained from comprehensive borehole surveys.

Jan 1, 1973

By H. A. Johansen

Recent advances in the metallurgy of chromium have enabled this metal to begin to take its place among the refractory metals. Considerable work is being done on the development of high-temperature alloys containing high percentages of chromium.1/2/ In spite of the relatively large amount of work done on these alloys, little is known of the properties of the pure metal. Information in the literature concerning the tensile properties of pure chromium metal is quite scant. This deficiency maybe explained by the great difficulty of preparing test specimens from such a brittle material, resulting in many losses in each phase of the specimen preparation and testing procedure.

Jan 1, 1954

By R. Hogg

"The basic population balance models for agglomeration processes are reviewed and procedures are described for extending their applicability to systems with size-dependent rate constants and to the formation and growth of porous agglomerates from rigid, solid-particles. Simplified procedures for the further extension of the models to include simultaneous agglomerate growth and breakage are also described.INTRODUCTION The association of small particles into clusters or agglomerates is a significant factor in many facets of particle processing. Agglomeration processes are widely used to facilitate handling, storage and utilization of fine powders. Processes such as coagulation or flocculation are used to aid solid-fluid separation in dispersed particulate systems. Agglomeration also occurs as an accompaniment, often unwanted, to other particulate processing operations such as fine grinding, mixing and blending, transport and flow.Reliable agglomeration models are needed for improved understanding of the processes in general and of the complex role of numerous, interacting variables as well as for direct application to the design and control of industrial processes such as flocculation, granulation and pelletization. Ideally, the models should account for the primary forces responsible for agglomerate formation and growth, the effects of external forces on process dynamics, the development of agglomerate structure and its role in the process itself, and the effects of concurrent processes such as structure modification (e.g. compaction) and agglomerate breakage or degradation."

Jan 1, 1989

By A. A. Cochran

Methods of preparing small heats of steel containing radioisotopes were developed, and the techniques of stripping film autoradiography were used to detect and study the carbide and sulfide phases in titanium-bearing steels. Metallography had revealed areas of titanium sulfide and ferrite or pearlite adjacent to areas of titanium carbide and ferrite, and unidentified, irregular phases at the boundaries between these two areas. Sulfur 35 was used to deter-mine the extent of the titanium sulfide inclusions, and carbon 14 was used to delineate the titanium carbide phase. Individual radioactive areas were located with a resolution of approximately 10 microns. A general background exposure that was not correlated with microscopically visible phases was observed in the carbon 14 autoradiographs. The evidence from both sulfur 35 autoradiographs and carbon 14 autoradiographs indicated that the unidentified inclusions were sulfides rather than carbides. INTRODUCTION The use of radioisotopes to facilitate the work at the Rolla Metallurgy Research Center was expanded in fiscal year 1959 when the Bureau of Mines authorized the installation of an intermediate-level radioactivity laboratory. Before this time, sealed cobalt 60 sources had been employed for radiography, but no tracer work was done. The primary objective of the first experiments conducted in the new laboratory was to supplement physical metallurgy investigations of selected problems in steel research.

Jan 1, 1962

By Alton B. Cook

A material balance equation was derived for calculating (1) the initial oil volume and (2) the relationship of average reservoir pressure to net gas in storage in reservoirs used for natural gas storage operations. The equation is also applicable to secondary-recovery operations where reservoirs are completely repressured and gas cycled. Using this equation minimized two probable sources of appreciable error in conventional material balance calculations: inaccurate measuring of and accounting for produced gas, and differences between true reservoir pressure and average reservoir pressures as derived from bottom-hole pressure measurements. A new procedure is presented for calculating water encroachment. By solving the conventional material balance equation and the derived equation for gas storage simultaneously, the values for initial oil in place and net water encroachment can both be determined.

Jan 1, 1966

By Jr. Norman

Thermoelectric properties of depleted uranium selenides and tellurides were investigated from room temperature to 700 C. Several depleted uranium monoselenides and monotellurides were doped with selected cationic and anionic materials to determine the effect of impurity additions on the thermoelectric properties. The undoped uranium selenides and tellurides were semimetallic conductors exhibiting low Seebeck coefficients and electrical resistivities. Partial or complete degeneracy was in evidence, indicating a charge carrier energy distribution similar to that in a metal. Doping increased the Seebeck coefficients of the uranium monoselenides and monotellurides; however, the corresponding change in the power factor in the figure of merit was small because of the increase in electrical resistivity.

Jan 1, 1965

By BUREAU OF MINES

A complete list of permissible mining equipment, rescue apparatus and gas masks tested prior to January 1, 1925, was published in Bureau of Mines Technical Paper 3761. The present list includes all equipment tested and approved by the Bureau, up to and including January 1, 1926, and supersedes the list issued as Serial 27202 in November, 1925. It covers electric air compressors, coal drills, mining machines, mine pumps, room hoists, switches, electric cap lamps, flame safety lamps, electric hand and trip lamps, flash lamp, methane indicators and detectors, blasting units, storage battery loco- motives, power trucks, self-contained oxygen breathing apparatus and gas masks. The system under which these devices were tested permits the manu- facturer, after his equipment has passed certain tests prescribed by the bureau, to mark his equipment with a seal showing that it has been "approv- ed" by the Bureau of Mines. The tests are designed to insure that the equipment has the minimum requirements for safety in use. The only object of the bureau in making such tests and publishing lists of permissible equipment is to safeguard the lives of workers and to help lessen the hazards of mining.

Feb 1, 1926

By J. B. Janus

In connection with the purchase of coal under specifications for Government use, the Bureau of Mines in this report has compiled data on 81 mines located in 15 States. This annual report lists analytical data on the composition and quality of tipple and delivered samples of coal collected during fiscal year 1973. Tipple samples were collected by Bureau of Mines engineers at tipples as coal was being loaded into railroad cars or trucks. Ultimate analyses are given for most of the coalbeds listed. The deliveries were sampled at destination in accordance with instructions issued by the Bureau of Mines. All samples were analyzed in the Bureau laboratory at Pittsburgh.

Jan 1, 1973

By J. B. Janus

This report continues a series of analyses of coal samples made by the Bureau of Mines in connection with the yearly purchase of several million tons of coal for various Government agencies. Listed are the analytical data on the composition and quality of tipple and de livered samples of coal collected during fiscal year 1974.

Jan 1, 1975

By Leland H. Johnson, D. O. Kennedy, John Hyvarenen

"SUMMARYA chronological list of accidents at metal and nonmetal mines and quarries (excluding coal mines) in the United States in which five or more lives were lost has been compiled. Many accidents were described in more detail because of their unusual features. Tables have been included to indicate the number of major disasters and fatalities by the principal product mined, by State, and by 10-year intervals prior to 1945. The number of men employed to indicate man-hours exposed is unavailable; therefore, a true picture of disaster data by principal product mined, by State, and by 10-year intervals is not possible. However, the data are presented to indicate the causes of major accidents and bring to the attention of those affiliated with metal and nonmetal mines and quarries the hazards involved and lessons that can be practiced to keep such accidents at a minimum.INTRODUCTIONThe Bureau of Mines was requested to compile a chronological list of accidents at metal and nonmetal mines and quarries (excluding coal mines) in the United States in which five or more lives were lost. Data have been assembled on accidents from all causes in these mines and quarries from the earliest available information (describ¬ing an underground mine fire in Nevada in 1869) to the last reported major accident (a fire at a company-owned bunkhouse in Arizona in 1945).The accounts of the accidents were taken from articles in the technical press and from published and unpublished reports of the Bureau of Mines. Many of the accidents have been selected for more detailed descriptions because of the unique circumstances and to show the variety of dangers involved.Tables are included to indicate the number of major accidents, with resultant fatalities, by the principal metal and nonmetal producing groups, by State, and by 10-year intervals previous to 1945. The interval 1869-1875 does not cover a 10-year span because of incomplete records previous to 1869.ACKNOWLEDGMENTSThe information contained in this report was obtained from the Engineering and Mining Journal from 1874 to 1947, the Mining and Scientific Press from 1908 through 1922, from various published and unpublished reports of the Bureau of Mines and from reports by State departments of mines. Daniel Harrington, retired chief of the Health and Safety Division; E. H. Denny, supervising engineer, District H; R. M. Loucks, mining engineer; and other engineers of the Division contributed much valuable information and assisted materially in the study."

Apr 1, 1949

By J. H. Stears

This Bureau of Mines report presents information on the use of steel supports in U.S. coal mines, including accident statistics for a 3-yr period and a survey of present applications and problems. It also contains a summary of available steel arch configurations and a description of steel support design criteria for ground control applications.

Jan 1, 1984

By J. Shawn Peterson, David S. Yantek, Adam K. Smith

Exposure to excessive noise over time can cause permanent hearing loss. Workers in the mining industry are frequently exposed to A-weighted sound levels in excess of 90 dB. The A-weighted sound level at the roof bolter operator’s location can exceed 100 dB while drilling. The National Institute for Occupational Safety and Health (NIOSH) measured the sound pressure at the roof bolter operator’s position and utilized a phased array of microphones with beamforming software to identify noise sources on a roof bolting machine while drilling. The test data indicates the sound level at the operator’s position is dominated by the 2000 Hz through 5000 Hz one-third­octave-band sound levels. The beamforming results indicate that the drilling noise is primarily from two areas: the portion of the drill steel just below the rock and the drill steel-chuck interface. This paper will discuss the methods used to identify the primary noise sources.

By P. M. Daling, C. A. Geffen

The objectives of this study were to examine a representative cross section of formal safety analysis techniques developed for the nuclear and aerospace industries, to recommend those methods that would be suitable for application to the mining industry, and to include those methods in a user's manual. Volume XI of this report, the user's manual, describes several methods that were determined to be immediately transferrable to the mining industry. The handbook gives detailed instructions on appropriate application and utilization of the methods. Other techniques will require further development before they can be effectively transferred to the mining industry.

Jan 1, 1983

By Thomas E. Marshall, Gerald L. Finfinger

The Bureau of Mines has developed a practical methodology for deter- mining occluded gas contents of domal rock salt samples. The method, which is portable and field worthy, provides results in 5 min or less and does not require a laboratory environment or specially trained personnel to obtain meaningful results. The results can be used to identify gas-enriched zones, and thus may aid mine operators in production planning or ventilation design. The test method is based on the relationship between gas content and the acoustic response of salt samples as they are dissolved in water. The relationship is defined by an equation, and the results are repeat- able. The equation was derived by testing a series of rock salt samples collected from domal salt mines in Louisiana.

Jan 1, 1987

1. The following recommendations should apply to all mines, tunnels and underground quarries, but to opencast quarries only in so far as persons can be exposed to dust injurious to health. General In the present state of knowledge, all duets liberated in mining, tunneling and quarrying operations should be considered potentially injurious to health if breathed in sufficient quantity; dusts containing free silica should be considered specially injurious to health, the injurious particles being below 7 microns in diameter.

Jan 1, 1954

By P. G. Kovalchik

Overexposure to noise remains a widespread, serious health hazard in the US mining and other industries despite 25 years of regulation. Most categories of illnesses and injuries associated with mining have improved, with the exception of hearing loss. The drilling of rock in a confined work environment contributes to high levels of noise exposure in mining. The National Institute for Occupational Safety and Health (NIOSH) is conducting research to reduce the noise exposures of jackleg drill operators and to prevent additional cases of noise induced hearing loss (NIHL) by developing and evaluating low-cost retrofit noise controls for equipment. This report describes the procedure for the measurement and reporting of noise from portable pneumatic tools such as jackleg drills. The technique used in this research allows for the determination of the source A-weighted sound power levels and the radiation patterns in octave and 1/3 octave bands. Overall sound power level is also determined. This paper also reports the results obtained by using this procedure to evaluate a SECO S215 standard production drill and a CSIR Miningtek prototype rock drill incorporating engineering noise control measures. It was found that by using the manufacture?s recommended operating pressure of 496 kPa (72 psi) that the CSIR prototype?s sound power was 10 dB(A) less then that of the SECO S215.

Jan 1, 2009

By Harry W. Campbell

A mineral survey by Bureau of Mines personnel identified no mineral resources or mineral occurrences with development potential at prospects in the Mecca Hills Wilderness Study Area (WSA). Bentonite occurrences are in Skeleton Canyon and Surprise Canyon. Sand and gravel occurrences are numerous in and near the WSA. Much of the Mecca Hills WSA was leased for oil and gas exploration in 1983. No current mining claims or other leases were found in the study area. The Skeleton Canyon Clay Mine yielded clay to seal irrigation canals, Clay to seal ponds was also mined from the Red Top Clay Mine west of the USA. A sand and gravel pit south of the study area (near Box Canyon Wash) supplied material for local construction projects. A commercial sand and gravel pit was operating in 1983 near the mouth of Thermal Canyon 4 miles west of the WSA.

Jan 1, 1984

By J. H. Bilbrey

A recording thermobalance ,vas used to determine the rates of oxidation of mol-ten tin over the temperature range 550°-900° C. Oxidation rates were found to vary widely for a given temperature, as previously reported by other investigators. 1 X-ray diffraction data indicated that the probable cause of these variations was the development of preferred orientations in the crystals forming the oxide film. No reasons for the differences in degree of preferred orientation were discovered. For relating the weight of the oxide formed (w) to the time of oxidation (t) an equation of the form wn = kt was found to best represent the experimental data. INTRODUCTION In the course of conducting investigations on the feasibility of using selective oxidation techniques for the purification of various metals in the molten state it was soon discovered that data on the oxidation of molten metals and alloys were very scarce. In contrast to the many hundreds of publications on the oxidation of metals in the solid state there are relatively few articles on the rates of molten-metal oxidation. In view of this scarcity of data, it was decided to institute a series of investigations into the oxidation processes of molten nonferrous metals and alloys with the expectation that the information derived could be put to practical use in developing and improving refining processes based on selective oxidation. This report is the first of a series in which oxidation data for molten nonferrous metals and alloys are presented.

Jan 1, 1955