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By L. Cheng

This report presents the results of a Bureau of Mines laboratory investigation of the effect of water sprays in reducing respirable dust that escaped the face area of a full-scale wooden model of a mine en-try containing a wooden model of a ripper-type continuous mining machine and exhaust brattice. Areas examined were (a) the general effectiveness of a low-pressure water spray system mounted on top of the mining machine boom, a high-pressure spray system mounted under the boom, and the combined top-and bottom-spray systems, and (b) the effect of these three spray systems on the capture of coal dust particles of different sizes. Dust was injected into a sump cavity at the face. Airborne respirable dust concentration was mea-sured behind the brattice with a personal sampler and cyclone, and particle size distribution was mea-sured with a cascade impactor. When used alone, the top-spray system captured about 55 pct of the respirable dust in the face area and the bottom-spray system captured 60 pct; the capture efficiency of each system is decreased when they are used simultaneously. From a mass-concentration viewpoint, each spray system preferentially captures larger dust particles.

Jan 1, 1988

By Alfred V. C. Meyer

A Blastcorder4 was calibrated on the Bureau of Mines shaking table in the frequency range of 12 to 40 c.p.s. and in the amplitude range' of 0.25 to 1.0 g. The results of this calibration study show that in the frequency range of 12 to 30 c.p.s. the average accuracy of the Blastcorder is approximately ± 0.1 g.

Jan 1, 1962

By B. W. Dunning

This paper describes studies conducted by the Bureau of Mines to achieve its goal of developing methods for increased recovery and utilization of valuable constituents in a wide variety of domestic and industrial wastes, In this particular study, 36 units of obsolete electronic equipment from military aircraft were disassembled into their modular components by hand to determine materials distribution. Further modular disassembly into individual parts was used to identify metal composition. After identifying the metals in some of the more difficult to dismantle modules, similar modules were grouped together, shredded, mechanically separated, and using metal composition data from hand separation, classified along with the hand-separated materials. Although this equipment is normally classified as law-value iron-bearing aluminum, data were obtained that indicated the potential for moderately higher value classification. The electronic units were classified as to precious metals, copper, iron, and aluminum contents, and scrap values were estimated.

Jan 1, 1980

By Joseph M. Singer

This research project had two main objectives: (1) To identify the smoke limits of gaseous fuel-air mixtures and (2) to obtain and evaluate basic chemical information on the formation of smoke in very rich flames near the smoke limit. Such information would do much to establish the circumstances for car-bon deposition in gas appliances and in other types of combustors. Based on tests with ethylene and propane, these studies showed the following: 1. Smoke limits are related to the yellow-tip limits of the fuel. Previous research established sufficient data to permit prediction of yellow-tip limits on gas burners using a wide variety of fuels. The present study of smoke limits deals only with ethylene-air flames, but the concept that was developed is probably applicable to other fuels.

Jan 1, 1962

By A. George Stern

[In the examination of bentonitic clay suspensions used for oil-well drilling fluids3/ (and for other purposes, such as a core binder for foundry sand) it is important to have comparative tests for evaluating them. A satisfactory clay for these and other purposes should have the property of forming what is commonly called a "gel," but the measurement of this property has been a real problem. To date the solution has not been satisfactory, and some of the difficulties are considered in, this, paper, which describes a simple form of instrument (identified as an eykometer) for measuring the yield point under hydrostatic conditions of non-Newtonian clay suspensions, including those muds that are thixotropic. An oil-well drilling mud serves several functions, many of which depend on the "gel" characteristics of the mud. Among the more important functions are: (a) To plaster the sides of the hole to prevent caving of the walls; (b) to prevent the loss of the circulating fluid out of the hole by seepage; (c) to carry sand and cuttings out of the hole to the surface as they are formed by the rotary drill; and (d) when circulation of the fluid stops for shut-down or other unavoidable cause, to hold the cuttings in suspension by the setting up of the gel, thereby avoiding the difficulties that result when these cuttings are allowed to fall through the fluid and pack at the bottom of the hole.]

Jan 1, 1940

By David Schlain

The Bureau of Mines investigated methods for electrodepositing platinum-group metals from molten cyanide baths. The preparation of thick, protective coatings on molybdenum, Inconel, graphite, stainless steel, copper, and other structural metals were studied, as well as the electroforming of platinum and iridium crucibles. Iridium, rhodium, and ruthenium can be electrodeposited under an inert atmosphere, while platinum and palladium require the presence of air. Electrolytes may be prepared by direct-current electrolysis in NaCN or mixtures of NaCN and KCN using anodes of the particular platinum-group metal. When the concentration of metal increases to about 0.3 or 0.4 percent, the deposits become bright, adherent, and coherent. Current densities may be 10 to 25 ma/cm2, and plating rates are often 0.5 mil/hr. Platinum and palladium baths deteriorate because of the oxidation of cyanide to cyanate and carbonate, and the precipitation of metal. Changes in the platinum cyanide bath are relatively slow. The protection against oxidation afforded by the platinum-group metal coatings is evaluated by testing encapsulated specimens in a thermogravimetric balance. Surface pretreatment and the use of undercoats are discussed.

Jan 1, 1977

By R. V. Higgins, G. B. Shea

"FOREWORDIn the second year of World War II, the petroleum industry in California was taxed to near capacity to satisfy the expanded war demand for petroleum products, particularly fuel oil. With discoveries of crude oil in California declining and known reserves being depleted rapidly, conditions appeared to warrant study of the possibilities of utilizing the outcropping bituminous sandstone deposits in California for obtaining new sources of oil if the war should he prolonged. At conferences in Washington, D. C., with members of the Petroleum Administration for War and the Geological Survey, Bureau of Mines engineers emphasized the importance of determining the extent of those outcropping deposits of oil-impregnated rocks and of developing a practical process for commercial recovery of the contained bitumen to assure, if necessary, a supplementary supply of fuels. The desirability of such a study was recognized, and in July 1943 the Petroleum Field Office of the Bureau of Mines at San Francisco, Calif., in cooperation with the Geological Survey and the Petroleum Administration for War, initiated a study of the bituminouss sandstone problem. It was agreed that all mapping and geological work in connection with the study would be done by the Geological Survey, all engineering studies in developing a process for extracting the oil would be carried out, by the Bureau of Mines, and that the Petroleum Administration for War would aid in final adoption of the results in the field if circumstances warranted such action.Deposits of bituminous sandstones in California occur principally in the immediate region of the Coast Range mountains, notably at Pt. Arena, in Mendocino County, about 110 miles north of San Francisco; near Santa Cruz, in Santa Cruz County; in the Edna area in San Luis Obispo County; in the Sisquoc area in Santa Barbara County; and in the Ojai and Santa Clara Valleys in Ventura County. 4/ In addition oil-bearing sands outcrop near McKittrick and Maricopa, in western Kern County, and along the east edge of the Kern River oil field. Among the several prominent deposits of these source materials, those occurring near the cities of Santa Cruz and San Luis Obispo, and the town of Sisquoc are the largess."

Oct 1, 1948

By Patrick D. Plumb

The Juneau Office of the U.S. Bureau of Mines has undertaken a study of the environmental permitting process for major mines in Alaska to identify the effects ecosystem management has had or could have on the permitting process. To date, ecosystem management affects major mine permitting in Alaska primarily through the NEPA environmental assessment process. In Alaska, only the Forest Service has instituted ecosystem management in an overt and organized manner, while other agencies are doing so less directly. In recent Bureau of Mines publications, the mine permitting process has been described using case studies of several recently permitted mines in Alaska. The insights into the permitting process and the conclusions of these reports are reviewed and summarized. Several ecosystem management issues were identified in the case studies, including the need for: effective communication between agencies; standardization and coordination of NEPA environmental impact assessment and environmental monitoring programs among agencies, and assessment and selection of alternatives based on risks to ecosystems regardless of jurisdictional boundaries or environmental media-specific regulations. Ecosystem management could be used as a way to systematize, organize, standardize, and coordinate permitting and monitoring requirements and management perspectives among government agencies and project proponents.

Jan 1, 1993

By A. George Stern

In the examination of bentonitic clay suspensions used for oil-well drilling fluids3/ (and for other purposes, such as a core binder for foundry sand) it is important to have comparative tests for evaluating them. A satisfactory clay for these and other purposes should 'rave the property of forming what is commonly called a "gel," but the measurement of this property has been a real problem. To date the solution has not been satisfactory, and some of the difficulties are considered in, this, paper, which describes a simple form of instrument (identified as an eykometer) for measuring the yield point under hydrostatic conditions of non-Newtonian clay suspensions, including those muds that are thixotropic. An oil-well drilling mud serves several functions, many of which depend on the "gel" characteristics of the mud. Among the more important functions are: (a) To plaster the sides of the hole to prevent caving of the walls; (b) to prevent the loss of the circulating fluid out of the hole by seepage; (c) to carry sand and cuttings out of the hole to the surface as they are formed by the rotary drill; and (d) when circulation of the fluid stops for shut-down or other unavoidable cause, to hold the cuttings in suspension by the setting up of the gel, thereby avoiding the difficulties that result when these cuttings are allowed to fall through the fluid and pack at the bottom of the hole.

Jan 1, 1940

By O. P. Hood, G. St. J. Perott, S. P. Kinney

"FOREWORD (By O. P. Hood, Chief mechanical engineer).During the war certain suggestions concerning power production were made by Mr. Walter E. Trent to the War Inventions Board, and at the request of the War Department facilities for experimental work were provided on the grounds of the. Bureau of Standards.The experiments were along the line of controlling the conditions of combustion in a closed space. In order to reduce slag troubles, experiments were carried out for removing ash from powdered coal. After the war, work along this line was continued, resulting in the Trent Process, which agitates or beats together powdered coal, water and oil.A new technology had previously been given to ore preparation by the use of small quantities of oil in water with froth flotation, and although the methods, results and mixtures of the Trent Process were quite different, yet the same physical phenomena of differential wetting used, and the possibility of there being interesting results in fuel technologic was evident. A cooperative agreement was entered into, whereby the Bureau of Mines was to investigate the underlying physical and chemical facts and make them public, and the Trent Corporation was to pay the cost of the investigation.The several reports as made have been available to any one interested, and are now to be published. While the Bureau of Mines felt justified in investigating the physical phenomena so far as might be done in a laboratory, and so far as public interest might reach, no attempt was made to discover the commercial possibilities which development might bring. The question of commercial possibilities must be left for commercial enterprise to answer."

Jul 1, 1921

By James L. Elder, J. P. Capp, James J. Dowd

The Bureau of Mines and the Alabama Power Co., jointly, conducted the first experiment undertaken in the United States in underground gasification of coal in place, at Gorgas, Ala. Milton H. Fies, manager of coal operations, Alabama Power Co., proposed the cooperative investigation to Arno C. Fieldner, chief, Fuels and Explosives Branch, Bureau of Mines; and assisted in supervising the experiment. The objectives of the experiment were to determine whether coal in place could be burned successfully and whether the burning could be controlled; the effect of the fire on the coal bed and the overlying strata; and the yield and quality of gas that could be obtained.

Aug 1, 1947

By Wilbert J. Huff

The organization of the Explosives Division has been outlined in two preceding publications., The activities of the various units for the fiscal year 1939 are described hereafter: I. INFLAMMABILITY OF GASES AND VAPORS DETERMINATION OF EXPLOSION HAZARDS OF COMBUSTIBLE GASES AND VAPORS IN MINES AND INDUSTRIES (a) Determination of Limits of Inflammability of Gases and Vapors The following hitherto unpublished limits of inflammability were determined during the past fiscal year.

Jan 1, 1939

By Wilbert J. Huff

The organization of the Explosives Division has been outlined in two preceding publications.3/ The activities of the various units for the fiscal year 1939 are described hereafter: I. INFLAMMABILITY OF GASES AND VAPORS DETERMINATION OF EXPLOSION HAZARDS OF COMBUSTIBLE GASES AND VAPORS IN MINES AND INDUSTRIES (a) Determination of Limits of Inflammability of Gases and Vapors The following hitherto unpublished limits of inflammability were determined during the past fiscal year.

Jan 1, 1939

By Karl R. Becker

A variety of commercial detonators (fuse type and electric instantaneous and delay types) were subjected to impact and thermal stimuli to determine initiation stimulus levels and the dominant parameters in resistance to initiation. In the impact trials the detonators were impacted along their length to find the most sensitive region; threshold initiation limits obtained for these regions ranged from 3.47 to 20.82 joules (2.6 to 15.4 ft-lb). The friction sensitivity of the explosive component was an important parameter in determining sensitivity; various construction features of nonexplosive components played a role as well. In the thermal sensitivity trials, the detonators were heated from ambient to 100° C at an average rate of about 1.0° C/min, and thereafter at 0.5° C/min until they exploded; the explosion temperatures observed ranged from 121° to 188° C. These temperatures correlated quite well with the reaction temperatures of certain characteristic explosive components used by different manufacturers. The data also indicated an effect of confinement on explosion temperatures of detonators.

Jan 1, 1975

By C. Hellar

A new dual-boom remotely controlled roof bolter was designed, fabricated, and then tested in an underground coal mine. Remote-control functions allowed complete bolting cycles to be performed on two booms with both operators located within protective cabs. Capabilities included 3-to 6-foot-long bolts in 5-to 8-foot seams, limited to bolts 20 inches shorter than seam height. Machine was in compliance with all regulations including dust collection, machine lighting, and permissibility.

Jan 1, 1979

By John D. Spencer

Surveys to establish the quantity and quality of coals available for metallurgical, industrial, and energy use, investigations to develop better mining methods, and studies aimed at improving the health and safety of those who mine the coal highlighted Bureau of Mines research and technologic work on coal in 1968. Also being developed are more efficient methods of coal preparation, transportation, storage, and utilization. Supplementing this effort are projects designed to assure minimum disturbance of land, water, and air resources. Research centers and laboratories of the Bureau of Mines are listed in appendix A. Publications released during 1968 are cited with the various projects and in appendix C. Organizations that cooperated in the work in various ways are cited in appendix B.

Jan 1, 1969

By J. R. Cobble

As part of the Federal Bureau of Mines project to develop new or improved materials for metallurgical furnace applications, the Tuscaloosa (Ala.) Research Center has conducted research to develop a reproducible laboratory test for evaluating the resistance of refractories to molten slags. Tests were conducted with a slag representative of slag used to produce mineral wool. A rotating cylindrical furnace was lined with the brick being tested, and it was operated at temperatures up to 1,660° C for periods ranging from 8 to 32 hours. The effects of such variables as slag temperature, rotational velocity, charge rate, and contact time on refractory erosion were determined. The research demonstrated the reproducibility of the test procedure developed.

Jan 1, 1980

[Determine how subsidence resulting from underground coal mining affects surface structures, and evaluate the usefulness s of the tiltmeter for monitoring foundation movement. Approach The Bureau of Mines is studying foundation response to mine subsidence in order to determine how subsidence-induced ground movements affect foundations in place directly above the mint. These investigations are essential if economic mitigation and repair techniques are to be made. In addition, commercially available tiltmeter are being evaluated (or use as a cost-effective monitoring technique. To study foundation response and to evaluate the tiltmeter system, full-scale model foundations were constructed, instrumented, and monitored for three years. Vertical and horizontal displacements, tilt magnitudes and directions, and observed damages were recorded. Displacements were compared with measured lilt to determine if the tiltmeter was tracking foundation response to subsidence, The Bureau developed a computer software package to aid in the reduction and analysis of the tiltmeter data.]

Jan 1, 1988

By Kenneth Eilerts

The development and operation of "combination wells"5/ have created new and unusual problems, many of which can he solved only if information is available concerning the properties of the fluids produced. Data as to the characteristics of the fluids at the relatively high pressures that exist in the reservoirs are especially important, and there is growing economic concern to know what part, if any, of the liquid recovered at the surface was liquid in the reservoir, As an extension of this problem, it is important to know, whether liquid will be formed in the reservoir as a result of isothermal retrograde condensation when the reservoir pressure is reduced. The pressure range of such condensation, if it occurs, is significant in the design of gas-recycling plants for maintaining reservoir pressures. In connection with the operation of such plants, it is particularly important to know how pressure and temperature will affect the yield of the liquid phase and the composition of the gas to be returned to the reservoir. It has not been possible to predict the behavior of these fluids that have high ratios off gas to liquid by comparing them with the behavior of low gas-liquid ratio fluids at identical pressures and temperatures. Such comparison fails because the proportions in which a component will be distributed between the phases of a system at any given temperature and pressure depend increasingly on the composition of the mixture as the critical temperature and. pressure of the system are approached. Because many combination wells are producing from reservoirs that have temperatures near the critical point, experimental date on the properties of the Fluids under reservoir conditions are particularly important at this time, To meet the immediate requirements of the industry for such experimental information, an equilibrium cell has been constructed at the Petroleum Experiment Station of the Bureau of Mines, Bartlesville, Okla. When adequate experimental date have been accumulated, it may be possible to make dependable estimates of the phase relations for high gas-liquid ratio fluids at the pressures anti temperatures characteristic of "combination-well? reservoirs.

Jan 1, 1940

By L. V. Clark, Arthur La Motte

"INTRODUCTION The U. S. Bureau of Mines in 1930 and 1931 made a study of the properties and characteristics of liquid-oxygen explosives (L.O.X.) at the request of one of the largest users, in order to determine and eliminate the hazards attending its use.This report deals with the examination of absorbents for L.O.X. to (1) determine their most desirable and most undesirable characteristics, (2) to find ways and means of desensitizing absorbents to mechanical shock, and (3) to determine the effect that such desensitization of absorbents has on the explosive Characteristics of L.O.X.ABSORBENT MATERIALS The absorbent used in driving the Simplon Tunnel, the earliest project in which L.O.X. was used, was composed of crude petroleum, soot, and kieselguhr. During the World War, powdered cork, soot, sawdust, powdered straw, or other similar powdered materials were mentioned in the German military instructions for use of ""liquid air"" explosives. At that time the common types of absorbent, materials were compounded ones containing the above ingredients as well as kieselguhr, paraffin, gas oils, charcoal, bituminous coal, etc.Kuryla and Clevenger4 investigated absorbents of the above type and made the following statement concerning them:"

Apr 1, 1932