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By R. S. Warfield

Several reconnaissance-type surface and drill core samples of Arctic Northwestern Alaska coals were taken during the summer field seasons of 1964 and 1966 for coking studies. Surface samples were taken from the Kokolik River and the Cape Beaufort areas; core samples were obtained from the Kukpowruk River and the Cape Beaufort areas. Only one Kokolik River surface sample possessed coking properties. This sample, representing an 11.6-ft coal seam, made coke approaching metallurgical quality when a 30-pct portion of selected blending coals was added. Four Kukpowruk River core samples, each representing the same 19-to 20-ft coal seam, were all of about the same coking quality. No differences of coke quality attributable to depth of permanently frozen overburden were found, but the data confirm previously reported information that the 19- to 20-ft coal bed is a potentially satisfactory base coking coal. In the Cape Beaufort area, a core sample with appreciable coking properties was taken at depth from a coalbed determined noncoking in a surface sample.

Jan 1, 1969

By Robert F. Chaiken

Burnout Control is a process developed by the U.S. Bureau of Mines for accelerating the burning of wasted coal fires in situ, while at the same time controlling the heat and fumes produced. The Albright fIre project is a fIrst fIeld trial of Burnout Control as applied to a coal waste bank. An exhaust ventilation system was designed and constructed and then operated over a 1-year period at the site of an existing abandoned mine land fire near the town of Albright, WV. While predicted exhaust gas temperatures of 900° C and thermal power levels of 5 MW were achieved at 20-to 3O-in H20 vacuum levels, problems were encountered with engineering designs, equipment breakdown, and fuel-rich combustion that curtailed the time period of satisfactory operation. Effective afterburning of the exhaust gases (as they were drawn from the bank) corrected the problems associated with combustion stoichiometry and led to high thermal outputs. It is believed that with (1) improvements in engineering design and construction, (2) better control of the afterburning process, and (3) the use of conventional stack gas air-pollution controls, Burnout Control can be applied successfully to a coal waste bank fire.

Jan 1, 1991

By A. W. BELDEN

Among the investigations that the Bureau of Mines is conducting witha view to increasing efficiency in the utilization of fuels belonging to or for the use of the Government is an investigation of the processesthat take place in a foundry cupola during a melt. Some observations on the results of cupola tests of cokes at the Government fuel-testing plant in St. Louis, Mo., the coke being fromcoal from many coal fields of the United States, have been stated in a previous bulletin.s Especial attention was given to the meltinglosses that resulted from the use of different grades of coke, light and porous or heavy and dense. These losses amounted in one instance to 52.5 per cent of the iron charged and showed, in convincing manner, the need of exact information in regard to conditions in the fuelbed of the cupola.b Melting losses of iron have been fully appreciated but little under-- stood. The fact that these losses were possible with either light or heavy coke led to the belief that by using small charges 80 placed that. melting would take place in that zone of the cupola where the highest heat and the smallest percentage of oxygen prevailed and by confiningall melting to this zone these losses would be eliminated and the economical use of practically any coke produced for metallurgical purposes would become possible. This widening of the field from whichcoke might be drawn for foundry purposes would serve to place the foundryman in an independent position as regards his source of supply, and would tend to conserve the better grades of coking coals, which are being rapidly exhausted, by making the poorer grades available for mixing with them. In order to investigate conditions within a cupola, the Bureau of Mines as a first step decided to install a commercial cupola, to sample the gases during their travel from the tuy~res upward, and to determine the temperature of the fuel bed.

Jan 1, 1913

By Albert L. Toenges

[During the past few years there has beer trend away from locomotive haulage of coal from the loading point to the preparation plant of bituminous-coal strip, miner to motorized. haulage. The question has arisen whether this is always economical, and the purposes of this investigation is to determine, if possible the economic limit for motorized haulage. The operators of strip coal mines and of open-pit ore mines have shown great interest in this problem, and it is thought that the findings of this investigation will. Provo helpful to them.]

Jan 1, 1938

By Paul Meadows

The Buckrange reservoir, Stephens field, Ark., is approaching the economic limit of production under present operating conditions. Over 100 million barrels of oil remaining in the reservoir will not be recovered by primary producing methods. The Bureau of Mines, in cooperation with the Arkansas Oil and Gas Com-mission, made the petroleum-engineering study presented in this report to aid operators in evaluating secondary-recovery possibilities in the reservoir and in planning secondary-recovery programs if their initiation is decided. The Stephens field, in Columbia, Nevada, and Ouachita Counties, Ark., is about 12 miles northeast of Magnolia, Ark., and 15 miles west of the Smackover field. Surface elevations in the area average about 240 feet above sea level.

Jan 1, 1956

By Kenneth H. Johnston

Records show that waterflooding was tried in Osage County as early as 1934, but it was not economically important until a large unitized flood in the North Burbank field was begun in 1950. Development was rapid and by the end of 1960, there were 70 active water flood projects and 16 active pressure-maintenance projects in the County. The locations and status of the water-flood and pressure-maintenance projects in Osage County on December 31, 1960 are shown in figure 1, and information pertaining to these projects as of July 1, 1960 is given in table 1. For the past several years, Bureau of Mines petroleum engineers have arranged tours of selected waterflooding projects for the spring meeting of the Kansas-Oklahoma Water flood Association. These tours are conducted to demonstrate unique operating methods and new field equipment and to provide additional opportunities for exchanging information. Each of these tours has been supplemented by a published report describing in detail the projects visited. This report has been prepared for distribution during the 1961 spring tour of three waterflooding projects and a pressure-maintenance project in Osage County, Okla. (fig. 2).

Jan 1, 1961

By C. R. Hubbard

The Bureau of Mines investigated the mineral resources of the Upper Missouri River Basin as a part of a comprehensive water and related land resources study by six Bureaus of the Department of the Interior, coordinated by the Department?s Missouri River Basin Field Committee. The mineral resource study covers an area of about 18,000 square miles within the Great Plains physiographic province of central Montana. Exposed formations in the plains are chiefly flat-lying Cretaceous sediments. Plutonic rocks crop out in the central parts of the mountain uplifts, with steeply tilted Paleozoic sediments exposed around the margins. Oil and gas have been produced from several fields in the study area; total value exceeds $45 million. Coal-bearing formations of Upper Jurassic and Cretaceous age cover approximately 45 percent of the study area. Total production of coal since 1880 has been between 40 and 50 million tons, exceeding $75 million in value. Total metal production has been about $52.5 million. Industrial mineral production from 1925 through 1960, is valued at $24 million.

Jan 1, 1964

By C. R. Hubbard

The Bureau of Mines investigated the mineral resources of the Upper Missouri River Basin as a part of a comprehensive water and related land resources study by six Bureaus of the Department of the Interior, coordinated by the Department's Missouri River Basin Field Committee. The mineral resource study covers an area of about 18,000 square miles within the Great Plains physiographic province of central Montana. Exposed Formations in the plains are chiefly flat-lying Cretaceous sediments. Plutonic rocks crop out in the central parts of the mountain uplifts, with steeply tilted Paleozoic sediments exposed around the margins. Oil and gas have been produced from several fields in the study area; total value exceeds $45 million. Coal-bearing formations of Upper Jurassic and Cretaceous age cover approximately 45 percent of the study area. Total production of coal since 1880 has been between 40 and 50 million tons, exceeding $75 million in value. Total metal production has been about $52.5 million. Industrial mineral production from 1925 through 1960, is valued at $24 million.

Jan 1, 1964

By Clarence O. Babcock

Model pillars of limestone, marble, sandstone, and granite with length-to-diameter (L/D) ratios of 3, 2, 1, 0.5, and 0.25 (0.286 for granite) were tested to failure in axial compression to determine to what extent an increase in end constraint increased compressive strength. Adjustable steel rings, mechanically tightened about the ends of test specimens to create a radial prestress of 3,000 or 5,000 psi prior to the application of axial load, increased end constraint more than was possible in previous tests using solid steel rings. (Solid rings, epoxy-bonded to the ends of dogbone specimens, increased compressive strength compared with that of straight specimens without ring constraint.) During the loading cycle, additional end constraint was produced by lateral expansion of the specimens against the rings. The effect of the end constraint was to increase the compressive strength 55 to 58 percent for the shorter pillars of dogbone shape compared with the compressive strength of straight pillars with the same L/D ratios without ring constraint. Most pillars with L/D ratios of less than 2 were made stronger by end constraint. Pillars with an L/D ratio of 3 did not benefit significantly from end constraint. When the results from compression testing of straight specimens of rock in the laboratory are used to design mine pillars in situ, the pillars will be larger than necessary if the horizontal compressive stress is several thousand pounds per square inch greater than that resulting from the weight of the overlying rock alone. The L/D ratio can be increased by a factor of 1.76 for ratios in the range 0.25 to 3 and still provide the same compressive strength. The safety factor applied with straight specimen test results should also be acceptable for use with constrained pillar test results.

Jan 1, 1969

By Ludwig Schmidt

Large quantities of gasoline are lost each year by evaporation from bulk-storage station tanks. The rate of evaporation from bulk-station tanks is influenced by two principal factors: First, the vapor pressure of the gasoline in the tank; and second, the amount of "breathing" of the tank. The vapor pressures of the gasoline govern the amount of the gasoline vapor in the air-vapor mixture above the gasoline in a tank at a given temperature. This is one of the principal factors in determining the total pressure of the air-vapor mixture within the tank. The "breathing" of the tank is caused by the inflow of air from the atmosphere during certain periods of the day and the expulsion of the air-vapor mixtures at other times, caused by atmospheric variations. The pressure built up within a tank and the amount of gasoline in the air-vapor mixture are both a direct function of the temperature existing within the tank. Therefore, two of the most common methods for reducing evaporation losses from bulk-station tanks are: (1) The use of vapor-tight tanks equipped with relief valves and operated at 1 or 2 ounces of pressure and about .5-ounce vacuum; (2) reducing the temperature of tanks and their contents by painting them a light color, by insulation, and in some instances by using water sprays. Water sprays, although effective, usually are too expensive to operate economically. In order to determine and compare the effects of various colors, insulation, and pressure in reducing the evaporation losses of gasoline held in storage in bulk-storage tanks, the Bureau of Mines made observations from May 29 to October 15, 1930, on five horizontal tanks of 12,000-gallon capacity each, which were erected at the plant of Black, Sivalls and Bryson Manufacturing Co., Kansas City, Mo. This report gives in detail the results of these evaporation tests.

Jan 1, 1931

By A. B. Hooker, Ilsley. L. C.

"Several writers have called attention, in the technical press, to the possible failure of flame safety lamps in coal-dust laden atmospheres. Such writers question the safety or a flame lamp that has been proved only in atmospheres containing methane, believing that the resistance of the lamp to explosion would be lessened it coal dust constituted a part of the explosive mixture.If this be true, it follows that any series of tests devised to prove the safety of flame lamps for use in gaseous and dusty coal mines should not only embrace tests in mixtures containing various proportions of methane, but also in some of the tests the effect of adding coal dust to the explosive gaseous mixtures should be investigated.Some attention has been given this question by investigators, but the more common practice has been to make all tests in gas and air mixtures only, using methane when it was readily available. Apparently the English Accident Committee (1879-1886) who conducted tests upon 250 different lamps did not use coal dust in their tests. The first British requirements for the testing of safety lamps, issued as a result of the Coal Mine Act of 1911, made no mention of tests with coal duet.The Austrian Fire-damp Committee (1890) conducted a series of tests in which coal dust was used in some of the tests. In certain tests, the addition of coal dust apparently lowered the resistance of the lamp 1 meter per second. The Belgium investigators, Messrs. Watteyne and Stassart, conducted a series of tests in 1904 in which coal dust was used in a few tests without any marked difference in safety."

Dec 1, 1920

By Arne Landsberg

A study of the chlorination kinetics of germanium, silicon, iron, tungsten, molybdenum, columbium, and tantalum has been made to determine the effects of temperature, chlorine concentration, geometric surface area and gamma radiation. The reaction products were volatile at the temperatures used this making it possible to follow the reaction rates by weight loss of the solid. Chlorination rates of germanium, silicon, and iron were found to be directly proportional to chlorine concentration while the rates for tungsten, molybdenum, columbium, and tantalum were proportional to the 0.5 to 0.6 power of chlorine concentration. A good correlation of reaction rate and geometric surface areas was not obtained because the true surface area of the samples could not be measured. Intense gamma radiation had no effect on reaction rates. The Arrhenius activation energies determined over the temperatures used are as follows: Germanium, 27 kcal/mole (233°-241° C); silicon 33 kcaL/mole (375°-517° C); iron, cold rolled, 20 kcal/mGle (259°-325° C) annealed, 21 kcal/mole (293°-337° C); tungsten, 43 kcal/mole (617-776° C); molybdenum, 37 kcal/mole (445°-4910 C); columbium) 34 kcal/mole (229°?255° C); and tantalum, 29 kcal/mole (370°-449° C).

Jan 1, 1965

By John R. Rhodes

The objective of this project was to investigate the feasibility of analytical techniques potentially capable of determination of Mg, Al, Si, S, Ca and Fe in 1 to 2 mg samples of respirable coal mine dust, in a total analysis time of not more than 10 minutes per sample, using equipment capable of being truck mounted for field-laboratory operation. It was not essential that the technique be non-destructive, but the chosen technique is, and this enables the analysis to be performed directly on the 37 mm diameter membrane filter on which the respirable dust sample is normally collected. The sensitivity requirements are therefore quoted in terms of the units of measurement, µg/cm2. The detection limit (3o of the background criterion) should be 0.5 µg/cm2 or less. The precision should be 5% or better, at concentrations above which the detection limit is not the determining factor.

Jan 1, 1972

By Robert W. Van Dolah

On December 27, 1961, a fire and explosion destroyed the blasting agent mixing plant and an attached storage barn of the Whitaker-Atlas Supply Co., near Norton, Wise County, Va. Five residences, an office building, four trucks, and three automobiles were completely destroyed; a house trailer and several other trucks and automobiles were severely damaged; and other property damage, including much window breakage, occurred up to 3 miles or more airline distance away. Through the quick action of the fire marshal of the Norton Fire Department, Norton, Va., there were no fatalities and only five persons required hospitalization. This incident is of particular interest because of the widespread practice of mixing fuel oil (FO) with ammonium nitrate (AN) to prepare low-cost blasting agents, in many cases under conditions and circumstances not very different from those presented here. A representative of the Bureau of Mines Explosives Research Laboratory, Pittsburgh, Pa., and field representatives of the Bureau's Health and Safety Activities conducted the investigation. Information in this report was obtained from representatives of the Whitaker-Atlas Supply Co., the Norton fire marshal, and others who were on the scene either shortly before or after the incident occurred. Representatives of the Manufacturing Chemists' Association, the Institute of Makers of Explosives, and individual ammonium nitrate producers participated in the inquiries and investigations.

Jan 1, 1962

By James J. Snodgrass

A new technique was used to obtain detailed sonic logging data in drill holes above the water table at a coal mine site in northeastern New Mexico. The equipment was developed under contract to the Bureau of Mines and the U.S. Department of Energy to indirectly evaluate the in situ structural properties of coal and overburden. The system comprises a hydraulically operated, wall-clamping downhole probe compatible with standard four-conductor logging cable, and a surface control module. Resolution of layering is 0.6 meter (2.0 ft), and a redundancy of data from separate receivers provides accurate timing measurements. Preliminary results in the settled overburden of an excavated long-wall panel indicated a low average velocity zone, extending approximately 18 meters (60 ft) into the immediate roof of the coal seam. Subsequent measurements improved the field and recording procedures to produce high quality waveforms from which both P and S arrivals may be visually interpreted. Over a representative section of interbedded sandstone, siltstone, shale, and coal, Vp and Vs varied considerably even within lithologic units. Compressional wave velocity in the coal seam, Vp = 1,740 m/sec (5,700 ft/sec), was in the range of variability of published data.

Jan 1, 1982

By W. L. Acherman

The Bureau of Mines found the chemical and galvanic corrosion behavior of the TZM and molybdenum-30 tungsten alloys to be generally equal or superior to that of unalloyed molybdenum in many aqueous solutions of acids, bases, and salts. Notable exceptions occurred in 1 [N] nitric acid, where both alloys corroded appreciably faster than molybdenum. In mercuric chloride solutions, the TZM alloy was susceptible to a type of crevice corrosion which was not due to differential aeration. The alloys were usually not adversely affected by con-tact with dissimilar metals in galvanic couple experiments, but the dissimilar metals sometimes corroded galvanically. Both alloys were resistant to substitute ocean water spray at 60° C.

Jan 1, 1968

In 1967 the United States consumed 58.8 quadrillion Btu of energy. Both the Atomic Energy Commission and the Resources for the Future, Inc., a private economic forecasting group, predict that the United States energy requirements will reach 135 quadrillion Btu by the year 2000. In 1967 bituminous coal produced 21.4 percent of the energy used in the United States and anthracite coal another 0. 5 percent. Coal Reserves Coal reserves make up about four-fifths of the United States storehouse of fuel in proven reserves. Seventy-five percent of all fuel, likely to be found and recovered is coal. Electric utilities consume more than half of the bituminous coal mined in the United States in generating 53 percent of the nation's electricity. Atomic Energy Commission analysts have proposed the development of a vast "national energy system" based upon long-distance electrical transmission from abundant untapped coal reserves in the western United States. The study predicts that even if uranium supplies are available and economic breeder reactors developed, coal requirements for electricity generation will more than double by 1980 and increase another 50 percent before the year 2000.

Jan 1, 1970

By Chas. F. Jackson

During the past 5 years the Bureau of Mines has published information circulars dealing with mining methods and costs at 78 ore mines; 7 circulars, each of which is devoted to a discussion of one of the principal mining, methods; and 23 circulars dealing with special phases of mining, such as ventilation, shaft sinking, tunnel driving, the cost of equipping and developing prospects and small mines, underground transportation, diamond drilling, and ground support. These circulars were written by many different authors, and in order that the method of presentation and the basis for compilation of data might be the same in all the papers the Bureau drafted an outline to be followed in their preparation. To clarify the data in these circulars, which are in the libraries of many engineers and mining companies, and the summarized data presented in this paper, that portion of the outline dealing with cost and labor-performance data is reproduced below.

Jan 1, 1934

By H. M. Harris

The Bureau of Mines investigated chlorination of domestic ilmenites in a fluidized coke bed at temperatures of 950° to 1,150° C. Objectives were to develop an effective process for producing TiC14 suitable for TiO2 pigment and to reduce pollution by collecting and treating waste byproduct chlorides. The reactor for these tests was a 10.2-cm-diam quartz tube heated externally by electrical resistance heaters. It contained coke beds of from 35.6 to 82.5 cm in depth that were fluidized by 13 to 25 l/min of chlorine. Ilmenite concentrate powders were introduced at the bottom of the fluid-bed reactor, using the chlorine gas stream as a carrier. Test results showed that greater than 90 pct of the ilmenite reacted at optimum conditions and recovery of TiC14 ranged from 95 to 99 pct of stoichiometric. A temperature-controlled cyclone was used to remove high-boiling-point chlorides such as MnCl2, MgCl2, and FeCl2, and also collected fine unreacted ilmenite and coke dust. Impure TiC14 and FeC13 were separated by collecting the, iron chloride in a condenser con-trolled at 200° C. Titanium tetrachloride vapor was cleaned by passage-through a salt-column filter followed by condensation in water-cooled and refrigerated condensers. Liquid TiC14 was purified further by well-known industrial methods to meet specifications for pigment-grade chloride. Integrated tests were conducted in which chlorine, produced by dechlorination of FeC13 with oxygen, was recycled and used directly in a fluidized-bed chlorinator.

Jan 1, 1976

By R. V. Ramani, J. M. Mutmansky, J. Qin, J. Organiscak, R. Bhaskar

"The results of a two—year research study into the relationship between quartz dust levels in host material and in respirable dust in continuous mining sections are presented in this paper. The experimental design and sampling procedures for underground data collection are outlined. The sample analysis procedures for quartz determination, the ¬analysis results and conclusions of the study are discussed.The results of the study indicate that the quartz contents of the airborne dusts are generally higher than those in the host material and bulk samples; and the quartz content increases with decreasing size of the airborne dust. The source for quartz appears to be the roof and the floor materials rather than the coal seam itself. It also appears that the material containing quartz may be breaking into a different size distribution than coal.INTRODUCTION Without doubt, the potential for permanent and severe health damage exists due to respirable dust in the work environment. The attention directed at the reduction of respirable airborne dust to levels below those specified in the law and the achievements to date in meeting these standards are but a reflection of the recognition by many parties government, industry, and labor - of this potential and the need to reduce it.The ambient dust standard in underground U.S. coal mines (2 mg/s3) has a qualifier (Code of Federal Regulations, Title 30, Part 71.101) to determine an applicable dust standard when a respirable dust sample contains more than 5% quartz. This standard is frequently referred to as the ""reduced standard."" The reasoning behind the reduced standard is the relative toxicity of the quartz dust compared to that of pure coal dust. As the quartz levels in samples increase, the applicable standards become more stringent and maintaining the workings in compliance becomes increasingly difficult.The number of underground work locations operating under the reduced standards has shown a dramatic increase since 1980 (Figure 1). For comparison purposes, there were no mining entities operating on reduced standards prior to 1977. The emergence of this problem, which affects the health and safety standards on one hand and creates severe compliance problems on the other, has been rapid."

Jan 1, 1990