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By A. E. Lindquist

This Bureau of Mines publication identifies areas having sufficient coal reserves to support synthetic natural gas (SNG) development and summarizes those areas having the highest potential. Capital requirements, mining and coal cost factors, water availability, and coal-quality data pertinent to SNG production are presented. Evaluation of individual coal reserve blocks was based upon coal and water requirements of the Bureau of Mines Synthane coal gasification process.

Jan 1, 1977

By Peter H. Toepfer

Hydraulically emplaced, classified mill sands long have been used for stope fill. Entrained water drains rapidly from this type of fill through openings between the sand grains. Slimes are removed to facilitate drainage of the water, thereby lowering dangerous hydrostatic pressures in the fill. Use of unclassified mill tailing as practiced at the Dayrock mine is a recent development and represents a fundamentally different approach to the problems of inhibiting the development of hydrostatic pressures within the stope fill. At the. Dayrock mine, mill tailing is used to form a densely packed fill of sand and slime particles relatively impervious to additional water.

Jan 1, 1952

By James F. O'Neill

Brown iron ore resources in Barbour , Butler , Crenshaw , and Pike Counties were investigated in a drilling program and geological study by the Federal Bureau of Mines in cooperation with the Alabama Geological Survey and the University of Alabama . The aggregate footage drilled was 18,010 linear feet . When developed , reserves of 12,664,000 long tons of crude ore were indicated , containing from 26.9 to 29.0 percent iron and 0.2 to 1.6 percent manganese under a maximum overburden of 40 feet . Total inferred crude ore for the four counties was calculated to be 827,700,000 long tons . Beneficiation of samples by simulated log washing and use of a 1 / 8 - inch screen yielded from 46.8 to 51.7 percent iron and 0.2 to 2.6 percent manganese . Screen- test studies indicated no appreciable interlocking between the iron and manganese minerals and the waste particles of materials retained on a 200 - mesh screen . Clay was prominent in micron - size slimes . Silica was deleterious in the minus 20 - mesh size . While an indicated 2,198,000 dry long tons of usable iron ore can be recovered , sink - and - float tests show that it may be possible for 4,654,000 dry long tons to be recovered by other than log washing . However , applicable commercial processes have not been demonstrated .

Jan 1, 1965

By Warren Hastings

This paper describes the methods and costs, in units of labor end materials, of sinking a 7 compartment vertical shaft 1,261 feet through a fractured, water-saturated formation. The shaft, designed for hoisting 2,500 tons a day, is at Friedensville, Lehigh County, Pa., approximately 6 miles south of Allentown and Bethlehem. It was sunk by the E. J. Longyear Co. under contract to the New Jersey Zinc Co. Preparation for shaft sinking W8A begun July 1, 1947, and sinking was completed August 18, 1952. A total of 604,858 man hours was required to sink the shaft.

Jan 1, 1954

By J. H. Soulé

This information circular is one of a series published by the Federal Bureau of Mines describing methods and costs at various mining operations. The Schwartzwalder uranium mine, situated about 20 miles west of Denver, Colo., is an important source of uranium ore in the Front Range. Production was begun in 1953, and nearly 36,500 tons of ore had been shipped by September 1, 1958. The mine is operated by Denver-Golden Oil & Uranium Co., Denver, Colo. Much interest has been shown in the property since uranium mineralization tit was found by Fred Schwartzwalder in 1949. The Atomic Energy Commission, Federal Geological Survey, Office of Minerals Exploration (formerly Defense Minerals Exploration Administration), and Federal Bureau of Mines have done work in the area, and various private concerns have shown interest in the property.

Jan 1, 1960

By N. Greninger

The Bureau of Mines examined the possibility of a seasonal variation of respirable dust concentration in U.S. coal mines. The first step was to review company and MSHA-inspector dust samples that had been collected during the past several years in 14 selected mines for compliance purposes. Results indicated severe scatter in data; most standard deviations of the dust concentrations measured in winter and summer months were comparable in magnitude with the mean values of dust concentrations for the seasons. Therefore, a detailed statistical analysis was conducted. At the 90% confidence level, the company samples of three mines had winter means 0.15 to 0.54 mg/m3 higher than the summer means; six mines had negligible seasonal variations; and five mines had winter means that ranged from higher to lower than the summer means. Inspector data, however, were too sparse for analysis. In view of both the low frequency of occurrence of a seasonal effect and its wide scatter in several of the mines, the study was ended with the conclusion that seasonal varia-tion in respirable dust levels, in general, is an insignificant factor.

Jan 1, 1986

By Hillary W. St. Clair

The purpose of this investigation was to determine the practicability of refining crude aluminum-silicon alloy or aluminum scrap containing silicon and iron by selective dissolution in zinc of the aluminum from the alloy followed by distillation of the zinc from the aluminum.

Jan 1, 1949

By L. K. Weaver

The purposes of this Bureau of Mines report are to review the history of the domestic offshore hydrocarbon production; to project offshore oil and lease condensate production from 1971 through 1985; and to show the impact of offshore development on the onshore segment of the petroleum industry. Since 1954, offshore production has provided an increasingly larger portion of the domestic oil production. Domestic offshore oil and lease condensate production has increased from about 2.0 pct of the U.S. total in 1954 to 16.7 pct in 1970. Likewise, marketed gas production has increased from 1.0 pct of the U.S. total in 1954 to 15.0 pct in 1970. The past performance of exploration, leasing, development, and production of the offshore petroleum industry was used to make projections of offshore oil production. A comparison between onshore and offshore operations was also made. Assuming a tentative Department of the Interior offshore leasing schedule is completed by 1980, the authors estimate that by 1985, about 30 pct of domestic crude oil and lease condensate production from the lower 48 States will come from offshore areas. Currently, leasing of Federal offshore areas has been delayed due to environmental considerations. The rate at which off-shore hydrocarbons will enter the energy market will depend, to a large extent, on how soon environmental considerations are resolved. Assuming that offshore leasing will resume in the near future, U.S. offshore production of crude oil and lease condensate should be about 934 million barrels in 1985.

Jan 1, 1973

By Neal M. Muir, Robert S. Sanford, Bruce I. Thomas

"INTRODUCTION The presence of the zinc-lead-copper deposits an the north slope of Mount Eielson, Mount McKinley National Park, Alaska, has been known for many years. The deposits were examined by J. C. Reed, a geologist of the United States Geological Survey during the summer of 1931. In the summer of 1943 the authors and Clyde Wahrhaftig, a geologist of the Geological Survey, examined the deposits.ACKNOWLEDGMENTSIn its program of investigation of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the and that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual investigative work, and prepares the final report. The Metallurgical Branch, Oliver C. Ralston, chief, analyzes samples and performs beneficiation tests.Particular acknowledgment is due to Heine Kenworthy, who conducted the beneficiation tests under the supervision of C. Travis Anderson; to Clyde Wahrahaftig of the Geological Survey, who completed the Geologic and topographic maps, to Grant Pearson of the National Park Service; and to O. M. Grant and Mrs. Frank McGarvoy for their assistance during the examination."

Nov 1, 1947

By C. P. Lazzara, R. A. Franks, G. F. Friel, J. C. Edwards, J. J. Opferman

A series of four coal combustion experiments was conducted at the National Institute for Occupational Safety and Health's (NIOSH) Pittsburgh Research Laboratory (PRL) in the Safety Research Coal Mine (SRCM) to evaluate the response of fire sensors to a small 0.61 m square smoldering coal fire which transitions to flaming combustion in the presence of diesel emissions. An optical path smoke sensor alarmed earlier than a point type diffusion mode ionization smoke sensor which alarmed prior to a CO alert value of 5 PPM above ambient. The presence of steady state diesel emissions resulted in a decrease in the optical smoke sensor analog output voltage signal by less than 1.4 pct for the three coal fire experiments in which a diesel engine was operating, whereas the ionization smoke sensor output decreased between 10.8 and 26.7 pct after the initial surge of the diesel engine. A commercial diesel discriminating fire sensor did not alarm for a fire in the one experiment for which it was used. The results of the experiments demonstrated that an optical path smoke sensor might be used to detect a coal fire under the experimental conditions considered of starting a diesel engine followed by a slowly developing coal fire.

By Wallace W. Key

Mineral raw materials produced in California, other States, and foreign countries were purchased for consumption in quantities valued at over $60 million at 800 of the 1,200 chemical plants operating in California in 1960, according to questionnaires completed by company officials. These and other data received from mineral consumers, producers, dealers, and Government agencies formed the basis for this the first of a series of reports designed to present the intricate features and relationships controlling mineral raw material supply and demand in California industries. The results of this study indicated certain changes in use patterns of minerals in chemica 1 manufacturing; a shift in requirements from metals to nonmeta ls, from inorganics to organics, from natura 1 to synthet ic materia ls , and from distant to local sources of supply.

Jan 1, 1965

By Erik Sherer

Indonesia is poised to become a major player in the Pacific Rim thermal coal markets. Although the colonial Dutch developed numerous coal mines in the late 1800's for steamship bunkers and domestic fuel, Indonesia's coal industry has only recently begun to actively participate in the growing global marketplace. This export coal is primarily the result of the commercial development of coal mines in eastern Kalimantan by foreign contractors. From virtually no coal exports in the late 1980?s, Indonesia's coal industry has increased its exports to approximately 15 million metric tons (Mmt) in 1992. In 1992, Indonesia was the world?s sixth largest exporter of steam coal, By the year 2000, Indonesia projects that it will supply approximately 25 percent of the seaborne thermal coal requirements of the Pacific Rim countries. Although limited quantities of this coal may enter the European and U.S. markets, high qualities, low production casts, and favorable transportation rates will make Indonesian coals very competitive in the rapidly growing Pacific Rim markets. This study examines the Indonesian coal mining industry and compares it to the U.S. coal mining industry. This report is the sixth in a series of coal exporting country studies requested by the House Appropriations Committee. Previous studies examined the Colombian, Canadian, Australian, South African, Polish, and Venezuelan coal industries.

Jan 1, 1994

By Robert J. Evans

Reclamation costs were estimated for 20 coal surface mining operations in the Appalachian and Midwestern Coal Supply Districts (these two districts were divided into three multi-State regions). The cost data were obtained through onsite observations, interviews with mining company personnel, and the authors' cost estimating procedures. The cost data are presented in terms of dollars per acre, dollars per ton of coal produced, and dollars per cubic yard of overburden moved during backfilling. The reclamation process is divided-into three cost categories: Premining planning, backfilling, and revegetation. The average total reclamation costs for the three regions are $2.77 per ton of coal produced and $8,168 per acre. As the result of comparisons of reclamation costs by region, by mining method, by slope, and by size of operation, the most important reclamation cost difference is between area mining methods ($1.73 per ton) and contour mining methods ($3.81 per ton). The Federal Bureau of Mines conducted this study to determine as accurately as possible the actual costs involved with the reclamation of coal surface mined land done in conjunction with active mining operations.

Jan 1, 1975

By J. R. Nettle

A method has been developed in the laboratory for successfully electro-refining titanium metal. Refining is accomplished in e fused-salt electrolyte using offgrade metal as the anode and collecting the purified metal at the cathode. The characteristics and requirements of the various alkali chlorides tested as electrolytes are discussed in relation to relative ease of purification and serviceability. The various types of cells designed and tested for electrorefining are illustrated and their method of operation discussed. The individual advantage of each cell and the purpose for which it was designed are reviewed. The magnitude of the cathode current density was found to depend largely upon the quantity of soluble titanium chloride in the electrolyte. The physical condition of the anode also greatly affected the cathode current density.

Jan 1, 1957

By G. M. Kintz

In safety work a study of past accidents is of value in determining means of reducing future accidents of the same character. This is particularly true with reference to coal-mine explosions. Data from publications of the United States Bureau of Mines and from published reports of the State inspector of coal mines of Colorado are presented in this circular in the belief that they will be of value to operators by indicating methods of preventing future coal-mine explosions. The tables included are complete only with regard to major disasters. The Bureau of Mines considers as a major disaster one in which five 'or more men are killed. However, this circular also includes a considerable number of minor disasters, Various explosions in the coal mines of Colorado from 1883 to 1932, inclusive, are listed with information available as to their probable cause, number of men killed and measures which, if they had been in use at that time, might have prevented them. John McNeil, first Colorado State coal-mine inspector, on page 43 of his first report for the period ended July 31, 1884, made the following recommendations for the prevention of explosions in the coal industry: True causes could be traced either to insufficient ventilation, carelessness and lack of rigid discipline in carrying on energetic ventilation and other precautions needed to be enforced in a mine giving off explosive gases. *** When any quantity of fine coal dust is observed in an entry, air course, or room it should be made damp and be removed from the mine, and thus beep every place as free from dust as possible. *** A system of bratticing close up to the face of each and every place in the mine from crosscut last made (whether gas should just then show its presence or not) which should not be more than 50 or 75 feet according to the nature of the mine.

Jan 1, 1933

By J. C. Dumbrille

The following account of wining practices of the Kirkland Late Gold twining Co., (Ltd.), at Kirkland Lake, Ontario, is one of 4 series of papers being prepared by the United States Bureau of Mines on mining practices, methods, sad costs in various districts. The author has prepared this paper with the help and permission of J. B. Tyrrell and W. M. Sixt, the managing director and the mine manager, respectively. This mine is operating at a daily rate of about 150 tons.

Jan 1, 1931

By K. C. Dean

This report is the first of a series concerned with processes for producing magnesium. These reports will evaluate metallothermic, carbothermic , and electrolytic production methods, and will furnish a cost basis for comparing the processes. Areas deemed most promising for future research will be delineated for each procedure. This report presents briefly the history of the metallothermic process, and describes the operations of the Defense Plant Corp. (DPC) plants that employed the process. A hypothetical plant designed to produce 12,000 tons of magnesium per year, using ferrosilicon as a reductant, is described, and raw materials, energy, and major equipment requirements are estimated. Several process modifications are suggested for future research.

Jan 1, 1965

By W. H. Emens

[This circular is one of a series dealing with tie development and equip¬ment of small and medium size mines, and with the costs of such work prior to productive operation. The preparation and publication of these papers by the Bureau off Mines has been made possible through the cooperation of various min¬ing and development companies. The bureau of Mines has published a series of circulars dealing with min¬ing methods and costs at a large number of producing nines in the United States, Canada, Mexico, an, other countries. Unit costs of development work, shaft sinking, (rifting, crosscutting, tunneling, and raising are usually much higher in the preliminary development of a property than during its productive life.]

Jan 1, 1933

By H. Polat, Q. Hu, M. Polat, S. Chander

"The electrostatic charge on spray droplets of ionic surfactant solutions and coal particles was measured and the results were correlated with the dust collection efficiency. When various surfactant were added, the magnitude of the droplet charge increased significantly and it was observed to be a function of surfactant type and concentration. The concentration of maximum droplet charge coincided with surfactant concentration where maximum collection efficiency was observed for these surfactants. Particles of coal also carried substantial amount of charge magnitude of which seemed to be a function of coal rank.Based on the results presented in this paper, it was concluded that ionic surfactant primarily act as a strong electrostatic charge inducer for droplets. Due to interactions between these highly charged droplets and naturally charged particles, the efficiency of droplet-particle collisions play a primary role when compared to the wetting and engulfment phenomenon which could only follow a successful collision. INTRODUCTIONWater spray are widely used to suppress airborne dust in mine atmospheres (Walton and Woolcock, 1960; Kobrick, 1970; Hamilton, 1974; Jayaraman et al., 1986). Several investigators have considered the use of surfactants to enhance the effectiveness of water sprays especially for difficult to wet particles such as those of coal (Glanville and Wightman, 1979). The capture of dust particles by water droplets involves droplet-particle collisions, adhesion of particles to droplets, and engulfment of particles into droplets. Surfactants affect these sub processes through their influence on droplet charge, surface tension, and wetting. The last two mechanism have been thoroughly studied in recent years (Walker et al., 1952; Cohen and Rosen, 1981; Glenville and Haley, 1982; Chander et al., 1988; 1991). However, little attention has been paid to the role of electrical charge on particles and droplets on the collision and adhesion of spray droplets and dust particles."

Nov 1, 1995

By E. C. Lane

This paper is the second report of the results of the United States Bureau of Mines twenty-third semiannual survey of motor fuel marketed in the United States. The first paper, reporting data relating to gravity, vapor pressure, and distillation range of the samples, was published as Report of Investigations 31293. A third and concluding paper giving the results of other tests will be published as soon as these tests have been completed. The present paper deals with the data of the twenty-third semiannual survey presented in accordance with the revised specifications for United States Government motor gasoline. The sample numbers used are identical with those used in Report of Investigations 3129, with additional data included for copper strip corrosion (method 530.22),4 and sulphur content by the lamp method. Three hundred and twelve samples were collected and analyzed in this survey. Two hundred and seven samples were competitive-price gasolines and one hundred and five samples were premium-price motor fuels.

Jan 1, 1931