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By Robert C. Ellman

Stockpiles containing 2.3 million tons of lignite constructed in the period 1948-56 in conjunction with the construction of Garrison Dam on the Missouri River demonstrate successful stable long-term storage of lignite. Uniform and thorough compaction of each of the I-foot-thick layers by which the piles were constructed produced a bulk density of 70 Ib/cu ft. Air penetration into the stockpiles was restricted to a degree that prevents spontaneous heating or deterioration of the stored lignite, A continuing record of observations beginning with stockpiling operations in 1948 has been accumulated, This includes periodic fuel analysis, analysis of pile gases, and measurement of pile temperatures on the first large stock-pile, pile 5. This report describes the stockpiling method, the changes in heating value, pile gas composition, and pile temperature and summarizes observations from 1953 to 1964, Data accumulated attest to the stability of the stored lignite. The variation of the average heating value of periodic pile-depth samples is only 160 Btu/lb (11,990 to 11,830) on the moisture" and ash-free (maf) basis during almost 10 years of storage. Temperature levels of the pile interior are progressively decreasing. At pile surface, cyclic variations occur with the season. The only problem encountered with the large stockpiles is wind and water erosion of the pile surface. The partially successful control measures used are described.

Jan 1, 1967

By M. H. Chetrick

An important factor in the design and operation of a lignite-gasification plant is knowledge of the thermal requirements. These not only vary with different-size plants but also with the operating conditions for a plant of given capacity. Thermal data have been collected since 1945 from a commercial-scale lignite-gasification pilot plant operated by the Bureau of Mines at Grand Forks, N. Dak. The description and operation of this plant and a study of the gas-composition data have already been described in previous reports (1, 2, 3, 4, 5).2) / This investigation was made to review the thermal data taken in tests and to correlate them in terms of the fraction of undecomposed steam and the H2:CO ratio.

Jan 1, 1953

By Bernard M. Larsen, Clyde F. Williams, Edward P. Barrett

"Introduction.The Bureau of Mines at its Northwest Experiment station has been studying the production of sponge iron for the past four years, and during 1923 progress advanced to the point industrial applications can be safely considered. A furnace was operated commercially at silver City, Utah, producing about three tons of sponge iron daily.The Bureau was led to undertake this work by the interest in the use of sponge iron for copper precipitation and for conversion to iron and steel in the electric furnace.If a piece of iron oxide is completely reduced at such a low temperature (850 to 900° C) that no sintering or fusion takes place, then the piece of metallic iron formed has the same size and shape as the original piece of oxide on account of the removal of oxygen, the structure is finely porous, exposing a large surface of iron, and the apparent density is less than that of the original piece of iron oxide. This material is called ""sponge iron"". Chemically, it is a very reactive material."

Nov 1, 1924

By A. W. Decora

Gas-liquid chromatography has been applied to separating basic nitrogen compounds, such as pyridines and amines. Close-boiling compounds have been separated by exploiting structural and polarity differences, using selective liquid substrates dispersed on specially prepared solid supports. Development of these special supports was necessary in order to obtain symmetric peaks for basic nitrogen compounds; solution of this problem was important in applying gas-liquid chromatography to the analysis of basic nitrogen compounds found in shale oil. Attempts to analyze shale-oil tar bases by conventional gas-liquid chromatographic techniques, using Chromosorb4/ or Celite 545 as the support for a nonpolar liquid substrate, resulted in asymmetric peaks. These asymmetries were caused by adsorption of sample vapors on the solid support. Symmetric peaks were obtained when strongly polar liquid substrates were used on either Chromosorb or Celite. However, a solid support giving symmetric peaks only with strong polar substrates restricts the choice of substrate, and frequently, desired separations cannot be achieved.

Jan 1, 1961

By James Ridenour

The Gearhart Mountain Wilderness and RARE II area 6225 encompass 22,823 acres (9,236 ha) of the Fremont National Forest in southern Oregon (fig. 1). The area was studied under the provisions of the Wilderness Act of 1964 (Public Law 88-577). The U.S. Bureau of Mines determined the mineral potential of known mines, prospects, or mineralized areas, while in a separate effort the U.S. Geological Survey made geological, geochemical, and geophysical studies. MINERALIZED AREAS The study area contains no mining districts or known claims. Nearby occurrences of uranium, base metals, perlite, mercury, and diatomite apparently do not extend into the study area. Reconnaissance pan samples reveal only trace amounts of gold. No anomalous economic minerals were found in heavy mineral fractions of samples from stream beds draining the area.

Jan 1, 1982

By H. J. Hager, B. W. Gandrud, G. D. Coe

"INTRODUCTION The reduction of washery losses of marketable coal is a phase of coal preparation important to many of the Alabama coal producers. The problem has wide scope, and this report deals with but one of its several aspects. The investigation on which this report is based was made by the Southern Experiment Station of the Bureau of Mines with the cooperation of the Alabama By-products Corporation and the University of Alabama. The Alabama Byproducts Corporation provided samples of table middlings from its Colta washery on the Mary Lee bed at Flat Creek, Ala.PRACTICE AT THE COLTA WASHYAt Colta run-of-mine coal is crushed in a hammer mill in closed circuit with 5/16-inch square-mesh vibrating screens and tabled without classification on eight rectangular-deck wet tables. The coal is more friable than the bone normally present, and hence the bone is concentrated in the coarser sizes. An unclassified feed of this character can not be tabled with high efficiency to low ash content because of the sizing action of a concentrating table, which is such that when the tables are adjusted to exclude the coarse bone from the washed coal, a large amount of fine coal is lost in the middlings. At the time this investigation was undertaken there was no market outlet for middlings, with the result that middling products had to be discarded with the refuse."

May 1, 1939

By Arthur B. Johnson

The Bureau of Mines investigated the concentration characteristics of high-clay sylvinite ores from four potash companies operating in the Permian Basin near Carlsbad, N. Mex. These ores, containing 13 to 22 percent K20 and 3 to 7 percent clay slimes, cannot be effectively processed by current commercial flotation methods because of their high slime content. A solution to this problem was shown to be the use of two-stage moderate scrubbing conditions and washing of the ore as opposed to strenuous attritioning. Bench-scale physical beneficiation techniques for recovering potash minerals and the development of ore-dressing systems by flotation resulted in obtaining acceptable product grades and recoveries. By using a coarse grind, emphasis was placed on production of premium granular and coarse products. Flotation results showed that concentrates of 58.7 to 60.4 percent K20 with recoveries of 71.0 to 83.4 percent 0f the K20 values can be obtained.

Jan 1, 1971

By D. R. Tweeton

The U.S. Bureau of Mines, the University of Arizona, Sandia National Laboratories, and Zonge Engineering and Research Organization, Inc., conducted cooperative field tests of six electromagnetic (EM) geophysical methods to compare their effectiveness in locating a brine solution simulating in situ leach solution or a high-conductivity plume of contamination. The brine was approximately 160 m below the surface. The testsite was the University's San Xavier experimental mine near Tucson, AZ. Geo- physical surveys using surface and surface-borehole, time-domain electromagnetic (TEM) induction; surface controlled-source audiofrequency magnetotellurics (CSAMT); surface-borehole, frequency- domain electromagnetic (FEM) induction; crosshole FEM; and surface magnetic field ellipticity were conducted before and during brine injection. The surface TEM data showed a broad decrease in resistivity. CSAMT measurements with the conventional orientation did not detect the brine, but measurements with another orientation indicated some decrease in resistivity. The surface-borehole and crosshole methods located a known fracture and other fracture zones inferred from borehole induction logs. Surface magnetic field ellipticity data showed a broad decrease in resistivity at depth following brine injection.

Jan 1, 2010

By L. H. Banning

Recent dry-top electric smelting tests at the Northwest Electrodevelopment Experiment Station, Albany, Oreg., indicate that a high-titanium slag and a good grade of pig iron can be produced from alluvial Idaho ilmenite. A total of 120 tons of concentrates were smelted during this investigation, to yield an average of 0.5 ton of slag and 0.3 ton of pig iron per ton of ilmenite. Power consumption averaged 1,400 kv.-hr. per ton of ilmenite, at a feed rate of 400 to 500 pounds per hour, when operating at an electrical energy input of 290 to 370 kilowatts. The optimum operating voltage appeared to be 110 volts, phase-to-phase. Graphite electrode consumption averaged 15.6 pounds per ton of ilmenite smelted. Magnesite furnace refractory withstood the corrosive action of the hot metal and slag better than carbon refractory.

Jan 1, 1955

By Madan M. Singh

Hydraulic mining has been practiced in the United States since 1852 and many mineral commodities, such as gilsonite, phosphates, lead-zinc, silver ores and St. Peter Sandstone can be mined in this manner. In 1958, the U. S. Bureau of Mines initiated research into the mining of coal using these techniques.1-4 These early investigations were conducted in the 5000 psi pressure range. The large nozzle diameters used in this pressure range produced extremely high flow rates which created visibility problems at the coal face, and required removal of large amounts of water from the mining area. Besides, the production rates were not much better than with mechanical methods. This indicated that with higher pressures the water quantities might be reduced using the same or higher horsepowers but enhanced breakage. For this reason intensive investigation in material removal using fine water jets at extremely high pressures (50,000 psi to 100,000 psi) has been undertaken. This was not the entire reason for this contract from the Bureau of Mines, however. The contract objective is outlined later. IIT Research Institute has done pioneering work in high pressure jet development in the United States.5-8 Similar schemes have been investigated abroad. 9-13 Hydraulic mining of coal at relatively low pressures is successfully being done in the Soviet Union, Japan, Canada, and most recently, in Germany.

Jan 1, 1973

By Charles B. Carpenter

In general terminology, the West Texas Permian Basin companies the area south of the Texas Panhandle and west of the Bend Arch or Central Basin region. It is outlined more definitely by geologists however, as that area underlain by the south half of the Permian Salt Basin4/ and includes Scurry, Mitchell, Sterling, Howard, Glasscock, Reagan, Crockett, Upton, Midland, Martin, Gaines, Andrews, rotor, Crane, Pecos, Ward, Winkler, and Loving Counties in Texas, and.. Lea and Eddy Counties in New Mexico. The oil fields of the area, of which more than 70 have been discovered, are shown in fire 1. Approximately 4,200 producing oil wells have been drilled in these fields. Oil has been produced from limestones and dolomites of Permian age in most of the fields in the West Texas Permian Basin. Some of the fields produced oil from sandstone beds above the limestone, and in two fields production has been found below the limestone in formations of Ordovician age.

Jan 1, 1936

By Charles B. Carpenter

In general terminology, the West Texas Permian Basin comprises the area south of the Texas Panhandle and west of the Bend Arch or Central Basin region. It is outlined mere definitely by geologists, however, as that area underlain by the south half of the Permian Salt Basin4/ and includes Scurry, Mitchell, Sterling, Howard, Glasscock, Reagan, Crockett, Upton, Midland, Martin, Gaines, Andrews, Ector, Crane, Pecos, Ward, Winkler, and Loving Counties in Texas, and Lea and Eddy Counties in New Mexico. The oil fields of the area, of which more than 70 have been discovered, are shown in fire 1. Approximately 4,200 producing oil wells have been drilled in these fields. Oil has been produced from limestones and dolomites of Permian age in most of the fields in the West Texas Permian Basin. Some of the fields produced oil from sandstone beds above the limestone, and in two fields production has been found below the limestone in formations of Ordovician age.

Jan 1, 1936

By B. J. Scheiner

The Federal Bureau of Mines has successfully demonstrated an electrooxidation-solvent extraction-carbon adsorption process for recovering molybdenum and rhenium from offgrade concentrates. The flow sequence consists of dissolution of metal values by electrooxidation, liquid-solid separation by thickening, acidification and chlorate ion removal by sulfur dioxide treatment, solvent extraction to concentrate the molybdenum and rhenium, separation of molybdenum and rhenium by carbon adsorption, and metal recovery by crystallization. Molybdenum and rhenium were recovered as ammonium paramolybdate and ammonium perrhenate. Electrolysis of brine-concentrate pulps to generate a hypochlorite oxidizing agent in situ resulted in the dissolution of 98.9 and 99.1 pct of the molybdenum and rhenium, respectively, at an energy consumption of 13.7 kwhr/lb of molybdenum extracted.

Jan 1, 1976

The original work statement of this contract was entitles: 'A Accident Analysis Model for Use in Underground Coal Mines.' The contract was scheduled for a duration of 26 months and was to be in three phases: Phase I - Model Development, Phase II - Application of the Model, and Phase III - Installation, Monitoring and Evaluation of the Model. Alter three months in Phase I, it became apparent that much of the needed data for the model was nut available and could not be made available within the original study schedule. Proceeding as plumed would have resulted in a model of limited utility. Personnel from Theodore Barry and Associates and the Bureau discussed the problem in detail and mutually decided to utilize the majority of remaining funds to assist the Bureau in solving these data problems and develop a stronger ongoing capability for safety analysis within the Bureau. Both tie contractor and the bureau officials involved believed that this decision greatly enhanced the Bureau's ability to develop future accident prediction models, whose rigor would greatly exceed what was currently possible.

Jan 1, 1972

By Cecil Q. Cupps

Results are presented of a comprehensive study of the characteristics of the original oil in the Weber sandstone reservoir, Rangely oil field, Colorado. Through the medium of subsurface sampling, adequately representative samples of the original reservoir oil were obtained from many parts of the reservoir over a period of 5 years concurrent with active development of the reservoir. Data of differential gas liberation, pressure-viscosity, and. pressure-volume-temperature relationships are shown for 12 subsurface oil samples. Data also are given of reservoir pressure and. temperature, composition of liberated or solution Gas, composition of 22 produced-gas samples, and Hempel analyses of crude-oil samples from 18 wells. The characteristics or physical properties of the 12 subsurface oil samples, as determined by laboratory analyses, were correlated with elevation of the top of the Weber sandstone. These relationships of oil characteristics to elevation in the reservoir show that only the oil in contact with the initial gas cap was gas-saturated at the existing pressure and temperature. The characteristics of the original reservoir oil were marked by an appreciable decrease of saturation pressure and solution gas-oil ratio and increase of viscosity and density with depth below the gas-oil contact. The composition of solution gas and of' produced was also was found to vary with elevation of the oil in the reservoir.

Jan 1, 1951

By R. F. Waters

Laboratory-scale selective volatilization methods developed by the Bureau of Mines to recover germanium and gallium concentrates from coal fly ash and phosphorus furnace flue dust are summarized. In the better experiments between 85 and 98 percent of the germanium was recovered as the lower oxide and as sulfides, and between 75 and 97 percent of the gallium was recovered as the lower oxide and as the trichloride. Grades of the condensates were inconsistent and varied between a few tenths of a percent and 8 percent, depending on the method used. In the primary extractions of germanium alone the degree of enrichment surpassed 100 to 1, and for gallium the best ratio was 30 to 1. Upgrading of condensates by vaporization retreatment and by leaching and precipitation is discussed. An appreciable degree of mechanical preconcentration by attrition scrubbing and elutriation was possible on two fly ash samples.

Jan 1, 1967

By E. Chin

Under the seventh 5-year plan (1986-90), the Chinese Government continued to implement reform and to open the country further to the outside world in order to accelerate the growth of its national economy. As a result of expanded foreign economic exchanges and domestic achievements in education, science and technology, and cultural and public health undertakings, the national economy was strengthened. In 1988, there was impressive growth in the Chinese economy. The gross national product (GNP) grew by 11.2070 reaching $373.4 billion; 2 the national income grew by 11.4070 to $310.9 billion. The major problem in the Chinese economy was the imbalance between high demand and insufficient supply. Chronic shortages resulted in price increases and high inflation, which averaged 19% for China as a whole and about 30% in urban areas. Macroeconomic stability took precedence over market-oriented reform initiative. Because of rapidly growing inflation, the Government re-imposed price controls and rationing in major cities in the fall of 1988. China continued to be a major world producer of minerals, metals, and fuels. Output of the principal commodities continued to rise. The largest in-crease in production was salt which rose 24% in output in 1988; followed by sulfuric acid, 14%; cement, 12%; soda ash, 9%; caustic soda, 7%; and steel, 6%. For fossil fuels, the increase in output of natural gas was 14% in 1988; followed by coal, 3%; and crude oil, 2%. The output of electricity by thermal-fired powerplants rose by 9% while that for hydroelectric power-plants rose 7%. Although China's overall energy output has increased annually since 1980, the growth in demand continued to outstrip the supply.

Jan 1, 1990

By Elaine T. Cullen, Thomas W. Camm

The mentor/learner model is a time-honored approach to teaching, including within the mining industry. Miners know when they see excellence and have a deep respect for experts in their field. By using expert miners as mentors to other, less-experienced miners, training programs can be developed that will have a legitimacy and credibility that resonates with those being trained. Building upon concepts in current theories of adult education, this paper highlights the unique advantages of using mentoring as a teaching method that can make the educational experience both interesting and effective. Current NIOSH safety training materials use these concepts to deliver effective adult learning experiences for workers in the mining industry.

Jan 1, 2002

By Robert C. Johnson

Water-swelling fluormicas and fluormontmorillonoids were synthesized and described. They were found predominantly in the system Mg0 - MgF2 - Si02, with varying amounts of Li+ or Na+, Some water-swelling synthetic minerals were prepared with only strontium or lead in the twelvefold position, Water- swelling compounds containing either K+ or Ba+ were not found. The synthesized water-swelling products were shown by electron microscopy, X-ray diffraction, and chemical analysis to be typically two-silica-layer, platy compounds, Except for the complete substitution of fluoride for hydroxyl, the compounds were similar to the natural micas or montmorillonites. The stability and properties of the compounds were further established by electrodialysis, by differential thermal analysis, and by anion and cation exchange methods. Fluoride in the interlayer positions was nonexchangeable except through decomposition of the product. Exchanging the sodium or the lithium of the synthetic fluormicas or fluormontmorillonoids with potassium ion, particularly those derived from KOH provided a product from which a completely inorganic paper of extraordinary flexibility was fabricated. This paper had excellent mechanical and electrical properties except for water adsorption and a high power factor. Neither of these problems was solved during this investigation. However, papers with dielectric strength from 1,500 to 5,000 volts per mil were readily fabricated, particularly from the lithium containing fluormicas or fluormontmorill onoids.

Jan 1, 1963

By Daryl E. Radcliffe

The Bureau of Mines, as part of an agreement with the Bear Coal Co., Somerset, Col o., evaluated the response of a coal mine roof to time lapse. Time lapse, the interval between exposure and support of the roof, was studied using both instrumentation and statistics. Instrumentation studies were designed to equate displacement and rates of displacement with areas of roof left unsupported from 15 minutes to more than 4 days. A statistical study was completed to compare roof fall occurrence with time lapse intervals encountered during normal room-and-pillar mining. Results from this investigation show time lapse, in the Bear mine, to he insignificant with respect to roof stability after installation of permanent support.

Jan 1, 1980