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By McHenry Mosier

This is the fourth progress report in the series on the use of detachable rock-drill bits in the metal mines of the United States. It contains comparative statistics and costs or drilling at eight mines not reviewed in previous reports, comparison of the use of detachable bits at small mines and large mines, a discussion on the life of drill rods, and general conclusions derived from an analysis of the rock-drilling practice at all the mines investigated on this survey. This paper completes the descriptions of operating practice in rock drilling at individual mines. Data on drilling practices at 28 mines are given in appendices I and II and drilling costs are shown in appendix III. Research in the fundamentals of rock drilling, including the use of detachable bits, has been undertaken by the Bureau of Mines in its testing adit at Mount Weather, Va. Reports on the progress off this investigation will be issued when results warrant their publication.

Jan 1, 1937

By M. R. Geer

The Bureau of Mines examined the washability data for 25 Appalachian coals requiring low-density washing to reduce sulfur content to 1 percent, using the distribution-curve method. The purpose was to estimate how closely theoretical sulfur values could be approached, what yields of washed coal could be expected, and the recovery efficiencies that might be achieved. Assuming that the run-of-mine coal would be crushed to 3/8 inch and cleaned in dense-medium cyclones, the calculations indicate that theoretical sulfur contents could be approached closely when cleaning at a specific gravity of separation as low as 1.30. With coals that have favorable specific gravity compositions the recovery efficiency anticipated for cleaning at 1.30 specific gravity is surprisingly high. Similar calculations for cleaning with concentrating tables at intermediate specific gravities indicated that theoretical sulfur contents at 1.50 specific gravity could be approached closely with some coals but not with others. The calculations suggest that operating a table at a specific gravity of separation much lower than about 1.50 probably would be unsatisfactory with most coals.

Jan 1, 1968

By Albert L. Toenges, Theodore R. Jolley

"The development of Alaska depends on the existence of an adequate fuel supply in the Territory. The need to investigate coal deposits was recognized as early as 1911, when the first investigations were conducted in Alaska by engineers of the Bureau of Mines.Conditions existing in the Bering River and Matanuska coal fields, as found by Dr. Robert A. Holmes, former Director of the Bureau of Mines, are described by the Honorable W. L. Fisher, former Secretary of the Interior.4/Following Dr. Holmes' investigation, a party of Bureau of Mines engineers headed by R. Y. Williams visited the Bering River field in 1912 in cooperation with the Navy Department. A detailed examination was made of the Bering River field, and 855 tons of coal were mined from three prospects on Trout Creek. This bulk sample was delivered to the Navy for steaming and other tests. A description of the work of the field party and results of tests of the coal by the Navy Department and the Bureau of Mines has been published.During 1920 to 1922, the comparative steaming properties of Alaska bituminous coal, lignite, and wood were determined by the Bureau of Mines.6/In the early 1920's, the Bureau of Mines established a coal laboratory at Anchorage, where Alaska coals were analyzed. Subsequently, this laboratory was transferred to the Alaska Railroad and was used by the railroad for coal and other tests.Since 1910, the Bureau of Mines has made analyses of coal from Alaska, and the results of these analyses have been published.7/ The coal analyzed was obtained from mines, tipples, delivered lots, and face samples of coal deposits, and these samples were obtained in the field by engineers of the Bureau of Mines and geologists of the U. S. Geological Survey.Because of the shortage of petroleum and petroleum products in Alaska during the war, low-temperature carbonization assays of coals from the Broad Pass, Forty-Mile, Matanuska, and Nenana fields were made by the Bureau of Mines, and the results were published.Coal beds in the Matanuska field contain interbedded impurities in the form of shale, clay, and bone. The coal should be cleaned mechanically to obtain a satisfactory fuel. A coal-preparation study of bituminous coal from the Eska and Evan Jones mines was made by engineers of the Bureau of Mines, and the results were published.9/Coal production in Alaska is less than the requirements, and coal is imported to make up the deficiency. The cost of this imported coal is high. Greater production is necessary to supply coal for Army installations, industry, and homes. At present, there is only one bituminous coal mine (Evan Jones) in Alaska. The output of this mine is used at Fort Richardson, Anchorage, and by the Alaska Railroad. The economic life of this mine is limited (reported to be 3 years), and its closing, because of accidents or exhaustion, will cause great hardship to the inhabitants of Alaska. There is need to develop new, modern mines for the production of bituminous coal in the Matanuska field."

May 1, 1949

By David J. Kusler

This report describes a rapid, reliable, and relatively simple method developed by the Bureau of Mines Pyrometallurgy Laboratory at Bruceton, Pa., for determining lime (calcium oxide) and magnesia (magnesium oxide) in various materials containing these constituents in greater than trace amounts. Optionally, titania (titanium dioxide) may be determined for the same sample. The accuracy of the method, suitable for most purposes, is shown by comparing the Bureau results with those obtained by accepted procedures. The method has been applied satisfactorily to the routine analysis of blast-furnace slags, for which purpose it was primarily developed, and to other calcareous compositions. In the Pyrometallurgy Laboratory it has replaced the standard methods previously used to determine lime and magnesia, and has been in general use by that laboratory for the past several years. The analysis time, generally under 3 hours, is considerably less than required by standard methods.

Jan 1, 1960

By K. O. Bennington

Thermodynamic properties were determined by the Federal Bureau of Mines for lithium metasilicate (Li2Si03) and lithium disilicate (Li2Si205). Their enthalpies of formation were investigated by hydrofluoric acid solution calorimetry. The standard values are ?Hf°298 -393.8 ± 0.8 kcal/mole for Li2Si03, and ?Hf°298 -611.8 ± 1.0 kcal/mole for LiSi205. Enthalpy increments above 298 K were measured by copper-block drop calorimetry from 298 to 1,404 K for Li2Si03, and from 298 to 1,281 K for Li2Si205. Low-temperature heat capacities were determined adiabatically from 6 to 305 K for Li2Si205 only. The derived standard entropy is S°298 = 29.20 ± 0.10 cal/deg-mole. The various experimental data were combined with other data from the literature, and resulting properties of ?Hf°, ?Gf°, and log Kf were tabulated as a function of temperature.

Jan 1, 1976

A working understanding of present coal mine communications equipment and its usage is an essential prerequisite to the determination of future communications systems needs. As a means of gaining this understanding, a field survey program was planned and implemented. The plan formulated called for obtaining both qualitative and quantitative data from three main areas of interest: the types, physical condition, and performance characteristics of equipment presently used in the sample of mines to be visited; the relationship present communications has to safety and productivity; and the practical, future communications needs as derived through interviews with present mine management. In compliance with the original plan, the type and physical condition of equipment in use was found through at-mine interviews of personnel responsible for installation and maintenance. Further evaluation was made through the review of equipment instruction books and maintenance manuals and through in-mine inspection of communications equipment and signal distribution networks. The performance characteristics were determined through listening to conversations and noise levels and by talk-testing from randomly selected stations throughout each mine. System operation was evaluated by asking communication system users their opinions and by noting any difficulties personnel had using the systems.

Jan 1, 1974

By John Ward Smith, Neil B. Young

Shale specific - gravity to oil - yield relationships were developed for black shales of the New Albany Formation of Kentucky from data collected on core samples representing the complete section of the formation in three counties . Linear equations for estimating oil yield from measured specific gravity and for estimating specific gravity from measured oil yield were shown to be applicable within small error limits to all the sites tested . Variation in pyrite content is the largest source of error .

Jan 1, 1964

By Ralph H. Whaite

The Bureau of Mines program for microfilming maps of abandoned mines in the Pennsylvania anthracite region is described. A catalog of the maps that have been microfilmed in the Eastern Middle anthracite field--the first area to be covered in the program--is presented. Additional catalogs will be published as significant mining areas are completed.

Dec 1, 1964

By Daniel T. Rogers

The Bureau of Mines, in its alumina miniplant project to investigate alumina recovery from domestic, non bauxitic ores, has conducted research on the use of a hydrochloric acid leaching, gas sparging crystallization technology. An important element of this research is the efficient separation of undissolved, siliceous residue from AICI3 -bearing leach liquors by continuous, horizontal, countercurrent vacuum belt filtration. In an effort to calculate material balances quickly and to predict material balances based on different belt filtration configurations, the perfect-mixing-cells-in-series model (PMCS) for calculating material balances around belt filters was used. Because of the porous nature of the solids, the model produced erroneous material balances. Therefore a reliable model, the shrinking voids model, was developed postulating the presence of an unwashable voids liquor volume that decreases with decreasing liquor AICI3 concentration. This volume decrease postulation is equivalent to assuming that dilute liquors flow more freely, causing more voids liquor volume to become washable. Least-squares based computer programs are provided, which are useful not only in producing material balances from plant data but also in predicting balances for untested configurations using the same feed materials.

Jan 1, 1982

By Barry W. Klein

The U.S. economy was considerably stronger in 1976 than in 1974 or 1975. Real gross national product (GNP) rose sharply in the first quarter of 1976 and then increased at a more moderate rate for the remainder of the year. The unemployment rate fell until June and then increased for moat of the remainder of the year, finishing at the same rate as it had started the year. The inflation rate continued to decline in 1976. Reasons for the relatively low rate (compared with those of 1974 and 1975) included small increases in food prices and only moderate increases in energy prices. Total U.S. output measured in terms of GNP increased 11.6% in 1976. Real GNP in 1972 constant dollars rose 6.2%. Inflation as measured by the implicit price deflator increased 5.1%. In real terms, gross private domestic investment for residential structures rose 22.7% in 1976 after declining 14.7%a in 1975; State and local Government expenditures increased 1.4% in 1976; and personal consumption expenditures for services rose 4.5%. The Federal Reserve Board (FRB) index of industrial production increased 10.2%.

Jan 1, 1978

By J. O. Lewis, Carl H. Beal

The material for this paper was collected for the most part by C. H. Beal during the years 1916, 1917, and 1918. Many of the conclusions reached in regard to the life of oil wells have already been published by the Bureau of Mines 1 but those presented in this paper deal particularly with the theoretical aspects of oil production. The report discusses some of the fundamental factors governing oil production, taking up first the conditions affecting the. amount of oil in the oil sand, then those factors that control the rate of production of oil wells, and then discusses several related problems, most of which deal particularly with the effect of the production of one well on that of another.

Jan 1, 1921

By G. W. Jones, F. E. Scott

"INTRODUCTION During the last war, considerable attention was given to the search for materials or combinations of materials for use as expelling agents for aerosols in the well-known ""aerosol bomb."" These materials must be free of fire and explosion hazards under normal conditions of use.In cooperation with the Department of Agriculture and other Federal agencies interested in the work, the Bureau of Mines carried out a laboratory investigation on the inflammability of- dimethyl ether-dichlorodifluoromethane air mixtures. 4/The method of investigation was essentially the same as that used in a similar investigation dealing with the inflammability of propane-butane-dichlorodifluoromethane mixtures. 4/SOURCE OF MATERIALSThe dichlorodifluoromethane (commonly known as freon-12) and the dimethyl ether were supplied by Dr. Lyle D. Goodhue., U. S. Department of Agriculture, Beltsville, Md. It was reported that the freon-12 was manufactured by the Kinetic Chemical Co. Wilmington, Del., and the dimethyl ether by the Carbide & Carbon Chemicals Corp., Charleston, W. Va..The materials were obtained in small metal cylinders and were used as received. Before using, the cylinders mere placed in an upright position, and 5 to 6 liters of the gas was released from each cylinder to the atmosphere to remove any trapped air that may have been introduced when the cylinders were filled."

Sep 1, 1947

By Andrew J. Fergus

The purpose of this study was to provide basic information to aid further research on beryllium mineral flotation. Contact-angle and microflotation (Hallimond tube) methods were used to study collector action and flotation response of beryllium minerals and associated gangue minerals with representative commercial surfactants. Chrysoberyl received prime attention. Results indicated that selective flotation of beryl and chrysoberyl from fluorite and quartz is possible with sodium isooctyl phosphate below pH 2, and fluorite and topaz are readily collected by both anionic and cationic surfactants. Several modifying reagents were studied at one pH and one level of collector concentration. Aluminum sulfate, starch, and sodium silicate proved to be depressants in chrysoberyl flotation.

Jan 1, 1968

By Francis X. Cannaday

The purpose of this investigation was to find whether the moduli of elasticity obtained were the same for the following methods : ( 1 ) Deformation of a borehole in a prism subjected to uniaxial stress ; ( 2 ) deflection of a thin beam of uniform cross section uniformly loaded ; ( 3 ) sonic - pulse velocity measurements , and ( 4 ) strain measurements on a prism under uniaxial stress . The rock tested was chosen for its good elastic behavior and relatively good homogeneity and elastic isotropism . The same rock was used for all methods . Results indicate that for given environmental and stress conditions the moduli obtained by each of the four methods check one another within the limits of experimental error and that the differences introduced which are characteristic for each method are smaller than physical variations within the rock tested .

Jan 1, 1964

In March, the Minister of Mines, Mrs. Judy Erola, released a mineral discussion paper at the annual meeting and convention in Toronto of the Prospectors and Developers Association. Among the mineral objectives discussed was the revitalization of the "junior" mining industry. That industry reportedly has seen its share of total exploration expenditures fall from 50% in 1969 to 10% in 1979. Some sources believe the reason to be the rise of exploration costs and more- restrictive legislation The junior mining industry reportedly was responsible for 40% of all mineral discoveries in the 1969-79 period. CZECHOSLOVAKIA Czechoslovakia expects its capacity for the recovery of gallium metal to increase from 1,650 kilograms to nearly 3,000 kilograms per year by the installation of new recovery equipment at the aluminum plant at Ziar Nad Hronom in Central Slovakia. World production data are not reported, but the United States consumed 8,000 kilograms (estimated) in 1981, of which 5,536 kilograms were imported. Gallium is recovered as a byproduct of the Bayer process for the conversion of bauxite to alumina, and from certain zinc processing wastes. It is used for electronic applications such as light-emitting diodes for visual display panels in calculators, clocks, and other instruments.

Jan 1, 1982

By R. H. Nicholas

Shuttle cars have undeniably proved their worth as a means of transporting coal underground; however, several factors have arisen in connection with their possible improvement. This report .discusses the effect of shuttle cars that employ rough-tread and smooth-tread tires on mine roadbed, the amount of dust thrown into suspension by the use of such tire treads, and the service rendered by each type of tire. Involved, also, in this study are observations on the use of different amounts of calcium chloride on the haulageways.

Jan 1, 1949

By L. Kaufman

A range of processing conditions and compositions have been evaluated in order to optimize the properties of TiB2-(Ni,Cu) composites for application as a non-sparking tool material for use in coal mining operations. Fifty billets containing from 70 to 9S weight percent titanium diboride were hot pressed at 3000 psi between 2400°F and 2650°F. Samples which were cut from these billets were used to measure hardness, bend strength and impact strength so that composition/processing optimization could be effected. Eight compositions selected on this basis were evaluated by incendivity tests in order to choose the best composition. The best results were obtained for an 85 w/o TiB2-12 w/o Cu-3 w/o Ni composite hot pressed at 2650°F and 3000 psi. This material appears to be the best choice for fabrication of coal cutter bits to be evaluated in field tests.

Jan 1, 1973

By P. L. Woolf

Three trials with oxygen-enriched unheated blast air are described. The trials were conducted in the Bureau of Mines experimental blast furnace located in Bruceton, PA. The first trial utilized moisture addition to the oxygenated blast. The second and third trial were conducted with natural gas injection. The test was basically a feasibility study and in that regard the practice was demonstrated to be feasible and also have possible advantages over hot blast operation. The testwork was conducted in 1964 and 1965 as part of a continuing study of iron making technology in cooperation with several North American Steel Companies.

Jan 1, 1985

By W. W. Adams

Reports received by the Bureau of Mines, Department of Commerce, from State mine inspectors, for November, 1930, showed that 219 men were killed in the coal mines of the United States during the month, an increase of 25 over the previous month and 33 over November, 1929. On the other hand the production of coal decreased, the output of 43,329,000 tons in November being 8,397,000 tons less than in October and 9,005,000 tons less than in November a year ago. The larger number of fatalities accompanied by a smaller output of coal resulted in a higher death rate4 per million tons in November than in the same month last year or in October, 1930. The November rate was 5.05, as compared with 3.55 for November, 1929 and 3.75 for October, 1930. The increase in the rate for the industry as a whole was chargeable entirely to bituminous mines,, as the anthracite mines had fewer fatalities in November than in either of the previous months to which reference has been made. Reports for bituminous mines alone 'allowed that accidents at class of mines resulted in a death rate of 5.12, based on 195 fatalities and a production of 38,122,000 tons. This rate indicated an increase of 55 per cent over the rate for October, of the same year, and 72 per cent over the rate for November, 1929. The October record was 146 fatalities and 44,150,000 tons, and that for November a year ago was 138 deaths and a production of 46,514,000 tons. Twenty-four deaths occurred at anthracite mines in November, 1970: the output of coal was 5,207,000 tons, hence the rate was 4.61 per million tons. During the corresponding month a year ago there were 48 deaths and 5,820,000 tons of coal produced, which indicated a death rate of 8.25. In October, 1930, the death rate was o.34; based on 48 deaths and 7,576,000 tons.

Jan 1, 1930

By L. P. Larson

In this Bureau of Mines evaluation of the domestic supply position of tungsten, certain tungsten resources in the United States are estimated as to quantity and grade and then are systematically costed in detail (excluding exploration costs). A supply curve is developed which depicts the quantity of tungsten (WO3) up to about 15.5 million short ton units that is producible at calculated price levels ranging from about $13 to $125 per short ton unit. About 10.4 million short ton units are available at a calculated price that is less than the present market price ($40). Total known resources amount to about 40.2 million short ton units. A very large portion of that quantity was not costed due to inadequate information on either resources or processing methods. Further exploration and research would have a significant effect on the availability of tungsten in the United States.

Jan 1, 1971