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By Mayo D. Hercey, Edward W. Butzler

"Purpose and Origin of Investigation.For many investigations of mineral products such as metallic and ceramic materials, especially refractories, a knowledge of thermal conductivity and specific heat at high temperature is required. Such data have been needed by the Bureau of Mines for checking heat balances in kilns, and computing heat loss through furnace walls.Design of apparatus for thermal conductivity tests was undertaken by the Bureau early in 1922, an industry at that time indicated that no equipment intended for extreme high-temperature observations was elsewhere available or likely to be in the immediate future.The Bureau's investigation was begun by C. R. Greenslade, assisted by F. A. Hartgen, and temporarily discontinued owing to their resignations in the summer of 1922. The work was later turned over to the writers of this report, and has been carried forward at intervals, along with other problems."

Jan 1, 1924

By Richard S. Olsen

Prior work by the Bureau of Mines demonstrated a feed preparation method that eliminates the formation of slime during leaching of calcined kaolinitic clay and makes leached residues fast settling and easy to filter. Nitric acid leaching rates determined for calcined kaolinitic clay prepared by this method were found to correspond to a zero-order reaction model for both batch and continuous, stirred-tank leach-ing. A rate constant of 0.136 min-1 was determined. Separation of solid residues from the reacted slurry was examined, and filtration rates were determined. Permeabilities of the flocculated, leached residues were around 51 darcys, or 5.0 x 10-7 cm2 for laminar flow through 4-ft-deep beds.

Jan 1, 1983

By J. E. Gebhardt

External control of the electrochemical potential of a bed of mineral particles has been investigated by the Bureau of Mines as a method for controlling particle inter-action with organic collectors and thus, flotation response. A cylindrically shaped, 200-to 300-g bed of sulfide mineral particles was used as the working electrode to examine the potential distribution in the bed. The dissolved oxygen concentration of the electrolyte had a significant effect on the potential profile across the mineral bed. Low oxygen levels were necessary to achieve uniform electrochemical potential distributions. Flotation separation of a chalcocite-pyrite mineral mixture by controlled potential was achieved using ethylxanthate, but the flotation behavior of chalcocite and pyrite from the mixture does not follow the flotation behavior of the individual minerals. That is, the presence of another sulfide mineral alters the flotation behavior with ethylxan-thate. Galvanic interaction due to mineral-to-mineral contact between chalcocite and pyrite contributes to differences in the recovery. Chalcocite dissolution products had a deleterious effect on pyrite flotation by activating flotation below -0.1 V (saturated calomel electrode) and depressing flotation above -0.1 V. Pyrite dissolution products had no effect on chalcocite flotation.

Jan 1, 1985

By John C. Machisak

Employment and related injury experience of the coking industry in the United States for 1957 contained in this publication is summarized under three general sections: (A) General injury experience: Tables 1 to 9: Current and comparable statistics on operating data, number, frequency, and degree of severity of injuries and major accident agencies involved in the cause of Injuries. Data are presented for the industry as a whole, for each type of oven, and for the States in which coke was produced.

Jan 1, 1959

By Jr. Reistle

The tests reported in this paper were made in the East Texas field in the summer and fall of 1932 as a part of the Bureau of Mines study of the operation of flowing wells and reservoir performance; and to determine, if possible, the minimum reservoir pressure necessary to produce the wells in this field by natural flow through different sizes of flow strings. The minimum reservoir pressure that would be required to Maintain natural flow through 2 1/2-inch tubing was determined experimentally for the existing energy conditions in the East Texas field. With the present available data, however, it is impossible to predict accurately or to determine by calculation the necessary energy requirements for maintaining the vertical flow of oil and gas mixtures under all conditions. Although some valuable data were obtained which seem to have application to the solution of problems involving vertical flow, this important research of the petroleum industry is so involved that more study of the complicating factors influencing the flow of oil-gas mixtures through vertical pipes is required.

Jan 1, 1933

By William J. Campbell

This study was a part of two programs: The first, to develop and evaluate high-temperature refractories; the second, to investigate reaction-rate kinetics and phase equilibria in the sinter step of the lime-soda process for the recovery of alumina. High-temperature X-ray diffractometer techniques are to be used extensively in both programs. This paper summarizes developments in the field of high-temperature X-ray diffractometers through 1959, evaluates various furnace designs, and describes briefly the X-ray diffraction facilities of the Federal Bureau of Mines. A more detailed description of the equipment and its calibration is planned in a future paper on thermal expansion and phase inversion of rare-earth oxides.

Jan 1, 1961

By R. L. Rough

The Bureau of Mines analyzed rotary-coring-operations data to compare mud and air as coring mediums, and to compare core recoveries, penetration rates, and cost data for the respective mediums as part of an investigation of the susceptibility to secondary-recovery techniques of petroleum reservoirs in Ohio, Pennsylvania, and West Virginia. This report describes the rotary-diamond coring equipment and operations employed while coring 20 wells--10 cored using mud, and 10 cored using air. Data relevant to the draw works, rotary-table power, drill pipe, drill collars, core barrel, core head, mud pumps, or air compressors are tabulated. Average bit weight and rotary speed, core recovery, and penetration rates are listed for each formation cored. In general, core recoveries were better from the mud-cored wells, whereas penetration rates were faster for the air-cored wells. Coring costs were about the same for single-formation wells cored with either mud or air; however, costs increased considerably when multiple-formation wells were cored with air.

Jan 1, 1969

By M. S. Seehra, V. S. Babu, L. Farinash

"The diesel particulate matter (DPM), a constituent of the diesel engine exhausts, is known to be a potential carcinogen. 1- 3 Consequently, suitable methods to control/eliminate DPM have ·been under investigation in recent years. The DPM can be controlled by using fibrous ceramic traps. However, clogging of traps by DPM requires the impractical periodic trap replacement. Following the recent work by Garner and Dent,4,5 we are investigating the in situ use of microwaves to regenerate the ceramic traps, thereby eliminating the trap replacement step in this process. The use of microwaves instead of conventional heating for trap regeneration has the advantage of selective heating of the DPM instead of the trap, if the trap absorbs insignificant microwave power relative to the DPM. Also, the oxidation characteristics of the DPM are needed to understand fully this regeneration process.The rate of energy absorption P per unit volume of a sample is given byP = wE"" |Eo|2 • (1 )where w is the angular frequency, |E0|2 is the intensity of the microwave radiation, and E” is the imaginary part of the dielectric constant (E = E’ + iE”) . Thus measurements of E11 for DPM and ceramic trap material are needed to determine their capacities for microwave absorption. In this paper, we report these measurements carried out at · a frequency of 8.7 GHz. Following microwave absorption, the DPM is expected to oxidize. The oxidation characteristics of the DPM have been investigated using Fourier transform infrared (FTIR) spectroscopy of the evolved gases CO2 and CO and using thermogravimetric analysis (TGA). Finally, some information on the structure of carbon in DPM has emerged from the analysis of its x-ray diffraction spectra. Results of these experiments are reported in the following pages."

Dec 1, 1996

By Alvin Kaufman

Following the gold discoveries of the late 1800's much was written regarding the vast mineral resources of Alaska, and much interest was aroused, and yet over the years little has been done to exploit those resources. Between 1906 and 1935 the Kennecott copper mines of the Copper River region were the keystone of the mineral economy (fig, 1). After the depletion of the Kennecott ore reserves and aided by the statutory rise in the price of gold, the yellow metal became the major mineral commodity. In recent years it has shared the honors with coal and sand and gravel. Although this trend should indicate the development of a stable, diversified mineral industry, yet the trend of production is downward. This report results from a study by the Federal Bureau of Mines to delineate the problems and to forecast the growth of the mineral industries in Alaska. The need for such a blueprint for the future was enhanced by the population explosion in the United States and the consequent eventual need for additional living space, as well as the current interest in new areas, and the necessity to develop reserves of strategic minerals.

Jan 1, 1961

By J. D. Davis

On May 15, 1936, Congress authorized the Bureau of Mines to conduct certain studies, experiments, and. investigations of subbituminous coal and lignite.4/ Appropriations were made in July 19 7, and since that date an active investigation has been underway to complete the provisions of the act. Part of the investigation has included a comprehensive survey of the known properties of the lower-rank non-coking coals, and provisions were made to obtain more data on certain varieties. In line with this plan, a typical subbituminous coal was selected for an extended series of tests in the standard. Bureau of Mines-American Gas Association unit,5/ at the Central Experiment Station. This particular noncoking coal was the first one of its rank that had been tested in the apparatus; for this reason the results are of particular interest because the testing apparatus was originally designed for use in studying the coke- and gas-making properties of coking coals. The test as described below has been developed by the Bureau of Mines since 1927 through a cooperative agreement with the American Gas Association.6/ Ninety to 180 pounds of coal is heated in a circular retort, 13 to 18 inches in diameter, at wall temperatures ranging from 500°C. to 1,110°C. in 100°C. steps. All products are collected and measured; their physical and chemical properties are then carefully determined to ascertain the gas- and coke-making properties of the coal. During the last 10 years approximately 50 representative American coals have been tested in the Bureau of Mines equipment. The results on the first 30 coals and a complete description of the test procedure are contained in a joint publication of the Bureau of Mines and the American Gas Association.7/ The remaining twenty coals have been reported in Bureau of Mines reports as Technical Papers and Bulletins.

Jan 1, 1939

By R. E. Collom

The spontaneous explosion of charges of nitroglycerin placed in deep wells situated in parts of the Ranger and Caddo fields of North Texas has aroused considerable inquiry among operators end others as to the probable agency, or combination of conditions, which causes the explosion.The method now followed, under certain physical conditions of a well, of setting a charge of nitroglycerin and allowing it to explode spontaneously was discovered locally by accident. In certain deep wells where formations, overlying productive strata, cave upon withdrawal of casing, it has been the practice to fire the shot electrically. In some of these operations the electric wires are broken or the firing system is otherwise deranged by pulling casing or the caving of hole prior to the time for firing. Sucn accidents make it necessary for the driller carefully to clean cavings out of the hole to a depth close to the top of the charge, after which in the normal practice, an attempt is made to fire the charge by dropping a ""jack-squib"", fitted with a fuse and detonator, down the well. Mr. R. L, Fowler, production manager for the Pierce Oil Corporation, reports that a delayed shot was thus successfully tired through four feet of caved material lying on top of the nitroglycerin shells.When a shot destined to be fired electrically fails, because of the above mentioned accidental conditions to the electric firing system, much time is required for the driller to run casing into the hole and clean out caved material. It was during the time of such uncompleted operations that the spontaneous explosions first noted took place. Having noted these spontaneous explosions the well shooters now intentionally place a charge in deep holes, which because of probable caves would otherwise have to be tired electrically, and wait for the charge to go off. No detonators are placed with the charge.

May 1, 1920

By Robert H. Merrill

This Bureau of Mines report summarizes the design and tests of a gage that will simultaneously measure the deformation of a borehole along three diameters 60 degrees apart; the measurements are in a single plane normal to the axis of the borehole. The inherent errors in measurement are considered together with the problems associated with the use of the gage in the relatively severe environments in and around mine openings. These problems were treated in the design and tests of the gage and the results establish that the gage can be used to satisfactorily is determine estimates of the stresses in rock.

Jan 1, 1967

By Robert Goldstein

A computer program for calculating the illumination on coal mine surfaces due to machine-mounted lights is described. Utilizing numerical models of mining machinery and measured data on luminaire output characteristics, the program computes the ft-candle levels incident on the mine entry surfaces for any desired machine/luminaire/ entry configuration. Shadowing effects of the machine are taken into account. Results are provided at 2 ft. intervals on the face, left and right walls, floor and roof. To provide a data base for these calculations, eleven 3-D machine models were prepared and the outputs of three luminaire types were measured. Calculations were done for thirty different configurations.

Jan 1, 1977

By Dennis R. Dolinar

The National Institute for Occupational Safety and Health?s Pittsburgh Research Laboratory conducted a full-scale test of a composite polyurethane-aggregate seal in a hydrostatic chamber at the Lake Lynn Experimental Mine. This composite seal consisted of a polyurethane and limestone aggregate core that was formed between two concrete block walls. In the hydro-static chamber test, water is used to pressurize the seal. During the test, the maximum average water pressure the seal was able to withstand was 18.9 psi. Further, the seal began to yield at an average water pressure of only 17 psi. At the time of the test, the minimum seal design requirement was 20 psi under 30 CFR4 75.335 (2005). Therefore, based on this test, the seal did not meet the regulatory minimum design requirement. Uniaxial compressive tests conducted on samples from the polyurethane-aggregate core revealed that both the compressive strength and the elastic modulus of the material were much less than that for polyurethane only with a density of 10.0?12.0 lb/ft3. The significant reduction in the strength and stiffness of the polyurethane-aggregate mixture results from the formation of a soft polyurethane foam around each piece of aggregate. The formation of the soft foam seems to be caused by residual moisture from the aggregate. The moisture also caused the density of the polyurethane in the polyurethane-aggregate mixture to be less than the design requirements. The lower density of the polyurethane in the mixture, along with the formation of zones of pure polyurethane only, resulted in the overall seal density being less than the design requirements. During seal construction, steps were taken to control the moisture, but were not successful. An analysis of the seal failure showed that the calculated shear stresses at failure and the estimated shear strength of the polyurethane-aggregate mixture are fairly close. This suggests that the strength properties of the polyurethane-aggregate mixture along with a weak zone of poorly bonded aggregate controlled the maximum pressure the seal could withstand. At the time of the seal testing, the minimum design requirement was 20 psi, as specified at 30 CFR 75.335 (2005). New emergency temporary standards for seal designs were promulgated on May 22, 2007, with a minimum requirement of 50 psi under specified conditions. However, it will be shown that the evaluation of the polyurethane seal performance as designed to meet the older 20-psi criterion can be relevant to the design requirements under the new standards.

Jan 1, 2008

By F. G. Miller

[Petroleum tscknologists nnd progressive operatorr. constantly are striving to increase the percentage of oil thnt may be recorered from reservoir rocks through wells. The exhaustive studies that hve boen made of the function of natural gas in the production of oil, for example, havo aided operators greatly in increasing tho quantity of oil recovered from reservoirs. Natural gas dissolv.3d in and otheraiso asnociatod under pressuro with oil in rsservoir rocks, howovor, is not tho only source of energy available for rnovi~~ oil through sands to wells. In becomine Veservoi~enorgy conscious^^ encineera havo lonrned that in nnny petroleum resorroirs the edgewater flanking the oil accurrulation constitutos a potantinl source of enorgy cnpnblo, through pro1,sr control, of increasing oil-recovory officioncies materially. ?To longer is tho oncronchmont of mter into the oil- and gas-fillod uart of tho reservoir conridsred as evil to be combatted by dovious mothods but rnthar a nrtturrtl consequence, incident to the withdraval of oil nna gas from tho rolls, thnt mP.y be used nd~~mtngeoualy in lengthening the flowing life of wells ,md incre~sing the oconornic recovery nf oil and gns. Little is knom a3out tho nac'n-~nisrn by mhich wnter qor-rtos in driving nil through reservoir rocks, nnd thjro is n scnrcity of published informa- tion on rates of rnovzrnant of ~ntcr +,hat will result in naxilnm oil recoveries. Bureau of Xine s er.gir.ess nr r'reciate the ~aucity of scientific knowledge on the best methods of lying the natural rater drive to in- crease oil-recovery efficiencies arid ar9 initiating stildies that rill, they hope, contributo to tho procont small fund of information now available on the subject. This rh~.ort is s syr,o_nsis or brief c03pilation of published dAta and thought nccumulntod 30 far, groliminary to la-uorgtory ox~eriment+ tion NI& further resaarch on the principlgs und~rlying the nnturnl wnter drive RS it nffocts oil rocovory. The vrritors hopo th2t the omosition of available information prosentod in tho rey~ort rill stindate constructive thought and efforts loading torard moro comrlote extraction of oil and gas from resorvoirs.]

Jan 1, 1938

By George H. Holmes

Beryllium deposits in the northern Virgin Mountains , Clark County , Nev . , and Mohave County , Ariz . , about 70 miles northeast of Las Vegas , were investigated by the Bureau of Mines . The investigation indicated a widespread occurrence of beryllium- bearing pegmatites within an extensive belt of mica - schist . Several deposits with significant beryllium mineral concentrations were encountered . Only a few of the samples analyzed contained more than 1 percent beryllium oxide ( BeO ) ; in many of the samples , no beryllium was reported . The average tenor of samples from the more important occurrences was 0.25 percent BeO . Chrysoberyl is the predominant beryllium mineral in the pegmatite sills ; beryl predominates in the more massive bodies . Minute quantities of cesium and lithium minerals also occur , but no columbium , tantalum , or other rare minerals were found . Ore dressing tests on a composite sample containing 0.28 percent BeO which was representative of the pegmatite sills , indicated an 85 percent recovery of the chrysoberyl ( 70 percent recovery of total BeO ) by gravity concentration in a concentrate containing 17.6 percent BeO .

Jan 1, 1964

By Seth C. Schaefer

The Bureau of mines investigated thermodynamic properties of MnSO4 and 2CdO CdSO4 to obtain basic thermodynamic data applicable to the treatment of mineral concentrates during roasting and sintering processes. Standard Gibbs energies of formation were determined with high-temperature galvanic cells using stabilized Zr02 as the electrolyte. Potential measurements were obtained from the cells?

Jan 1, 1983

By W. D. Ryan

The organic act passed by Congress in 1910 instituting the Bureau of Mines provided that the director of the bureau should promulgate such investigations as might be necessary to determine the causes of mine accidents and the best methods of preventing them. With the object of accident prevention in view, Director Joseph A. Holmes, and others who were pioneers in the bureau, conceived the Plan of having first-aid and mine-rescue training as one of the major activities of the Bureau. Out of this plan grew the first-aid and mine-rescue contests, which have been featured as an incentive for men to take courses in this type of mine safety training. The first appropriation for mine-accident investigations became available on July 1, 1908, under the jurisdiction of the U. S. Geological Survey, with Dr. J. A. Holmes in active charge. During 1908 there had been some first-aid training in the Pennsylvania anthracite field and a start made in Illinois, although there appears to be no exact information as to when or where first-aid training in the mining industry first became a reality, it is generally conceded that the St. John's ambulance corps of Scotland was one of the first - if not the first - to make the work effective. In 1911, to celebrate the establishment of the Bureau of Mines and the formal opening of the Pittsburgh, Pa., station, a first-aid and mine-rescue demonstration was conducted on Forbes Field, Pittsburgh. President William Howard Taft and many other men notable in public life were 2 resent. This was the first general national contest of the kind held it the United States; and since then there have been a number of nation-wide first-aid and mine rescue contests, as well as some which have been international in scope. There are over one hundred first-aid and mine-rescue contests of various kinds held annually in connection with mining and the allied industries.

Jan 1, 1929

By J. S. Kennedy, R. G. Omeara

Beryllium is a strategic metal of ever-increasing peacetime importance because of the unusual properties of beryllium-copper alloys. These unusual characteristics are the combination of high strength and hardness, high fatigue resistance, and high wear resistance in alloys that have the corrosion resistance of copper. The principal industrial source of beryllium is the mineral beryl, a beryllium-aluminum silicate that occurs in pegmatites associated with quartz, feldspar, mica, and smaller amounts of various accessory minerals. The beryl is usually recovered in processing the pegmatites for the recovery of some of the other mineral constituents. Pegmatite deposits are found in various parts of the United States, but those in the Black Hills of South Dakota are the source of most of domestic production. The beryl marketed from the South Dakota pegmatite deposits occurs as coarse crystals, which are obtained by hand sorting. These pegmatites also contain other valuable minerals.

Jan 1, 1948

By J. W. Town

Recrystallization studies on chrome-bearing spinel materials were made by the Bureau of Mines to determine the effects of certain fluxing agents and cooling rates on the chromium-to-iron ratio of recrystallized spinel. Statistically designed and evaluated tests showed that the ratio of chromium to iron in naturally occurring chrome spinel could be increased from 1.5 to 1 to over 7 to 1 and that the ratio of chromium to iron in the chrome-spinel in a stain-less steel slag could be raised to over 18 to 1. Silica, magnesia, and lime had significant positive effects, while alumina had a significant negative effect. Cooling rates of 200 C per hour in a programmed spiral globar electric furnace were satisfactory for growing crystals of recoverable size.

Jan 1, 1967