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By H. C. Carpenter

Data are presented comparing results obtained with 17 different catalysts in hydrogenating crude shale oil to gasoline in single-pass operation. A method is described for predicting the maximum yield of gasoline obtainable at constant pressure for each catalyst from results of a limited number of experiments at different temperatures. Operating variables have considerable influence on yields and properties of products. With most of the catalysts, at operating temperatures below 890° F. liquid yield exceeded 100 volume-percent. Above this temperature the volume of liquid product decreased rapidly. Maximum gasoline production in most instances was achieved at a temperature higher than that at which the maximum volume of liquid product was produced.

Jan 1, 1959

By James R. Boyle

The value of Alabama's nonfuel mineral production in 1982 was $299.4 million, a decrease of $14.4 million from that of 1981; the decrease continued a downward trend that started in 1980. Output of most nonfuel minerals declined; cement, crushed stone, lime, sand and gravel, and clays were the major commodities produced in the State. Despite the decrease in mineral output, Alabama led the Nation in the production of crushed marble; was second in bauxite; third in ferroalloys and oyster shell; fourth in bentonite and dimension marble; fifth in common clay. fire clay, and kaolin; and sixth in masonry cement and lime.

Jan 1, 1984

By S. J. Hemberger, F. W. Lee, J. H. Swatz

"INTRODUCTION This investigation was undertaken in 1939 for the purpose of securing the necessary information relating to the field techniques and accuracy that would be needed for magnetically surveying State-wide areas. The Florida,peninsula was chosen for such a study for two reasons: First, because it is geologically ideal for such an investigation, since it comprises a series of unconsolidated, flat-lying Tertiary and Cretaceous sediments of low magnetic susceptibility covering a complex and much-folded crystalline basement comprised of rocks carrying strongly -paramagnetic materials; second, because information concerning the structural trends of the crystalline basement would be of great interest and Importance in the study of Appalachian orogeny and the relationship of the Florida Peninsula to both the Appalachian and Antilleantectonte systems. The results of this magnetic survey have clearly demonstrated that the magnetic anomalies reflect variations in the crystalline a basement. To the degree which the structures of the crystalline basement control the structures of the overlying sediments these results are useful for oil exploration.MAGNETIC OBSERVATIONSAll magnetic measurements were made with a vertical Aekania magnetic variometer having a temperature compensated needle. All observations were tied into two base stations located at Fort. Myers and Gaineeville, Fla. The absolute vertical magnetic intensities at these two bass stations were determined by the United States Coast and Geodetic Survey within an accuracy of + 10 gammas. The accuracy of the base station variometer used in the present survey was of the order of ± 3 gammas. The sensitivity throughout the survey of the magnetic variemoter used on the traverses approximated 30 gammas per scale division and it is estimated that the probable error between stations along a traverse would be about + 5 gammas. Measurements were started on traverse C near Fort Myers and tied into the Fort Myers base station established by the Coast and Geodetic Survey. Twelve traverses, comprising 1,500 station observations, wore occupied between the Fort Myers and Gainsville base stations. When the cumulative total of these 1,500 interim observations was tied into the Gainesville base station it was found to differ by only 30 gammas from the value obtained by the Coast and Geodetic Survey for that base. The observations were adjusted for this difference."

May 1, 1945

By D. B. Taliaferro

Information regarding the pores or voids in reservoir rocks is vitally important in the scientific extraction of petroleum from natural underground reservoirs, and petroleum technologists concerned, with subsurface, conditions have devised various methods that give reasonably accurate information as to the porosities of oil and gas-bearing sands.5/ In this, work, several investigators have made use of the experience of the ceramic and other industries. The method of determining the effective porosity of oil sands described in this report falls within the general classification of gas-expansion methods. It was devised and developed at the United States Bureau of Mines Petroleum Experiment Station, Bartlesville, Okla., as a part of the research dealing with fluid and energy relations in reservoirs and improved oil-recovery methods. The apparatus and procedure are well adapted to the requirements of the Bureau, and the following detailed description has been prepared so that others may make use of the information. A tabulation at the end of the report gives the results of several hundred porosity determinations for oil sands in fields of 11 States.

Jan 1, 1937

By D. B. Taliaferro

Information regarding the pores or voids in reservoir rocks is vitally important in the scientific extraction of petroleum from natural underground reservoirs, and petroleum technologists concerned. with subsurface conditions have devised various methods that give reasonably accurate information as to the porosities of oil and gas-bearing sands.5/ In this work, several investigators have made use of the experience of the ceramic and other industries. The method of determining the effective porosity of oil sands described in this report falls within the general classification of gas-expansion methods. It was devised and developed at the United States Bureau of Mines Petroleum Experiment Station, Bartlesville, Okla., as a part of the research dealing with fluid and energy relations in reservoirs and improved oil-recovery methods. The apparatus and procedure are well adapted to the requirements of the Bureau, and the following detailed description has been prepared so that others may make use of the information. A tabulation at the end of the report gives the results of several hundred porosity determinations for oil sands in fields of 11 States.

Jan 1, 1937

By Murali M. Gadde, John A. Rusnak

Rock mass classification systems are extremely useful for site characterization and have been employed by the rock mechanics community for several decades. While empirical in nature, the classification systems provide a viable means to quantify the nature of rock mass, which is necessary for stability analyses. In U.S. coal mines, the Coal Mine Roof Rating (CMRR) is the most widely used classification system for several purposes, including sup-port selection, chain pillar design, assessing the stability of extended face cuts, etc. The Analysis of Roof Bolt Systems (ARBS) is an empirical method developed from the CMRR to guide selection of roof bolts as the primary support system in U.S. coal mines. In this paper, the experience of Peabody Energy in applying ARBS to sup-port design is discussed. In general, data from the Peabody mines show that ARBS predictions match well with field conditions. Peabody, however, does not use ARBS as the stand-alone methodology for support selection. Peabody uses a two-pronged approach in which the support requirement is initially estimated from the classification method, and then numerical modeling is used to select the proper reinforcement system. Such an integrated approach is necessary, as ARBS suggests only the “amount of steel” that may be used to support the roof and does not specify which type of roof bolt to use. A case study is used to demonstrate the usefulness of ARBS and Peabody’s integrated approach to support design. Also, the application of ARBS at several Peabody mines showed a very good correlation with support cost. The correlation indicated a direct relation between bolting cost and the ARBS value.

Jan 5, 2007

By P. L. Woolf

Seven evaluation tests with blast furnace iron bearing burden materials are described. The effects of pellet strength, fines in the burden, decreasing slag volume, pellet size, eliminating stone with superfluxed sinter, and eliminating stone by prefluxing the pellets were determined. Fluxed pellets and fluxed sinter made with the same ore fines were compared. The tests were conducted under cooperative agreements between the Bureau of Mines and North American steel companies. The objectives were to improve blast furnace practice, expand and develop understanding of the operation and theory, quantify the effects of changes, and explore the limitations of operability. This work was part of an extensive program of blast furnace research in experimental blast furnaces at Bruceton, PA conducted in the years 1958 to 1967.

Jan 1, 1984

By Britt H. Hatfield, Jiu-Chiuan Chen, Wen-Ruey Chang, David C. Christiani

Occupational exposures to whole-body vibration (WBV) at different frequency domains may differentially affect human comfort and the musculoskeletal system. Under this presumption, a frequency-based weighting scheme has been adapted in many widely accepted standards for WBV measurement. However, there is very little human data showing a direct link between WBV frequency and musculoskeletal disorders. We conducted an epidemiologic study to examine the association between WBV frequency and prevalence of low back pain (LBP) and to identify determinants of specific frequencies associated with LBP in urban taxi drivers. Methods The WBV frequency data were collected from 247 professional drivers (aged 44.6±8.3) who participated in an exposure validation study 1 of the Taxi Drivers’ Health Study (TDHS) in 2000. 2 In accordance with the ISO 2631-1 (1997) methods, we measured the frequency-weighted acceleration over drivers’ seat surface, under conditions representing randomly assigned destinations. We developed a WBV record-replay system at the Liberty Mutual Research Institute (LMRI) in Hopkinton, MA, USA. This system includes two tri-axial accelerometers (PCB Piezotronics, NY, USA), one RD-130T PCM data recorder (TEAC, Tokyo, Japan), and one LMWBV meter 2.0 (LMRI, MA, USA). Only the vertical axis of seat-surface WBV frequency was used in this study. To characterize the WBV frequency curve, we manually identified the presence of any peak within each of the following frequency range: <4, 4-10, 10-20, and >20 Hz. Information about the operating vehicles and driving environment was either collected from the vehicle registration record (manufacturer, year of make, transmission, engine size, etc.) or directly measured (wheel-base length, seat inclination, etc.). Structured interviews were conducted by an occupational physician to gather information on LBP that had led to medical attention or absence from driving in past year. We used multiple logistic regression to estimate the prevalence odds ratio (OR) associated with the presence of each index peak frequency, adjusting for age, body mass index, professional seniority, daily driving hours, seat inclination, and the intensity of predicted root-mean-square WBV exposure in m/sec2. For any revealed WBV frequency that was associated with LBP, we constructed a multiple logistic regression model to identify the personal and vehicle characteristics associated with the presence of WBV peak within the indicated frequency range.

Jan 6, 2006

By John D. Foulkes

A study to categorize and characterize underground metal/non-metal mining operations from the viewpoint of telecommunication requirements and practices. The objectives were to: ? Gather and analyze data; ? Identify communication requirements; and ? Recommend systems for operational emergency and post-disaster telecommunications.

Jan 1, 1979

By Albert W. Deurbrouck

Twelve samples from six Barbour County coal beds were analyzed for this report. The samples collected were generally high sulfur content coals, frequently exceeding 3 percent in the raw-coal sample. Many of them could not be upgraded to acceptable metallurgical standards even by rigorous preparation procedures. The production of coal in the county in 1963 amounted to almost 3 million tons of which 44 percent was mechanically cleaned.

Jan 1, 1965

By Stephenson. E. L.

"INTRODUCTION In the spring of 1942 a series of magnetometer surveys on deposits of black sand underlying Pleistocene raised marine terraces along the coast of southwestern Oregon was nada by the Division of Geophysical Exploration of the Federal Bureau of Mines in cooperation with the Oregon Department of Geology and Mineral Industries. A few preliminary tests had been made in the same area in May 1940 and December 1941.The sands contain fine gold and metals of the platinum group, and, beginning in 1852, extensive, but spasmodic mining and exploration have been done for these precious metals. There are many old placer, mines and prospects, although for the most part the yield of the metals has been small. The sands also contain other minerals of potential value, including ilmenite, magnetite, garnet, zircon, and particularly chromite, and the wartime demand for domestic chromite resulted in extensive testing and development of the known deposits. The purpose of the magnetometer surveys was to determine the efficacy of, magnetic methods in tracing and outlining these known deposits and in prospecting for new ones. The field work was done between March 17 and May 29, 1942, by the author assisted by W.W. Paulsen of the Oregon Department of Geology and Mineral Industries."

Jun 1, 1945

By S. A. N. Sheya

Many gold-bearing ores in the Western United States also contain small amounts of mercury. The presence of mercury creates potential pollution and health hazards during several steps in gold processing. An investigation was undertaken by the Bureau of Mines to develop techniques for removing mercury from cyanide mill solutions by selective electrowinning to reduce the potential hazards. Sixty-five percent of the mercury was selectively electrowon from synthetic carbon strip solution at applied potentials of 1.00 to 1.50 V when using a mercury-coated platinum or copper plate cathode. Increasing the active surface area by using mercury-coated copper wool resulted in up to % pct of the mercury being electrowon from mill carbon strip solutions that contained 1.9 to 20 ppm Hg, 20 to 345 ppm Au, and 0.35 to 39.5 ppm Ag. About 98 pct of the silver was electrowon with the mercury onto the mercury cathode. Gold extraction ranged between 0 and 20 pet. Results of the investigation showed that choice of cathode material was critical to the success of the process. Selectivity was not achieved using uncoated steel wool cathodes.

Jan 1, 1988

By W. T. Benson

The nickel-bearing laterite deposits in the Pine Flat and Diamond Flat areas, Del Norte County, Calif., were investigated by the Bureau of Mines to determine the extent and nickel content of the two deposits and the amenability of the ores to metallurgical treatment. The work was based on drill-hole sampling and metallurgical tests in which attrition scrubbing and sizing, reduction roasting, and magnetic separation were used. Results of the sampling indicated that the deposits are comparatively small and are marginal or submarginal in grade. Metallurgical tests showed that no separation of cobalt from nickel and iron was made by sizing; however, a large portion of the chromium was separated. Reduction roasting and magnetic separation did result in upgrading the iron, nickel, and cobalt, and the simultaneous rejection of chromium.

Jan 1, 1963

The Mine Safety and Health Administration (MSHA) defines an independent contractor as “any person, partnership, corporation, subsidiary of a cor-poration, firm, association or other organization that contracts to perform services or construction at a mine.” Contractors that perform specific types of work are required to report the number of employees who work at coal mines and noncoal mines.

Sep 1, 2007

By F. S. Crawford

This report deals with the effectiveness and economy of installing mine timbers treated with preservatives in long-life service locations. Early in the present century, when mine timbers and labor were plentiful, it was not general practice to install treated timbers in such places. Because national sources of good mine timber are declining steadily, the mining industry must now conserve timber. Moreover, the cost of installing and replacing mine timbers has been rising. Therefore, even the simplest of treatments can be expected to give some return on the investment when applied to timbers that are to be installed in relatively permanent locations. Better methods of treatment will produce better returns. In a service test of maple timbers treated by the hot-and cold-bath method and installed in main haulageways of the Athens mine of the Cleveland Cliffs Iron Co., Negaunee, Mich., zinc chloride-treated timbers had an average useful life of 13.3 years; borax-treated timbers, 11.2 years; and sodium fluoride-treated timbers, 7.7 years. Untreated timbers used as controls had an average useful life of 3.8 years.

Jan 1, 1950

By George A. Morgan

The 53 countries that constituted Africa in 1989 accounted for a significant portion of total world output of a number of mineral commodities. Among the most significant minerals to be produced in Africa were andalusite, antimony, asbestos, bauxite, chromite, coal, cobalt, copper, diamond, fluorspar, gold, lithium minerals, manganese, phosphate, platinum-group metals, and the titanium minerals-ilmenite and rutile, vanadium, vermiculite, and zircon. Despite the underdevelopment of much of Africa, mineral raw materials played a very important part of the national economies of many of its countries. In terms of percent-age of export earnings, minerals accounted for more than 90% in some cases. In several countries with agrarian economies and little economic diversification such as Angola and Guinea, a single mining operation could represent an important source of foreign exchange. These latter operations tended to be the more easily mined surface deposits of diamond, gem stones, and precious metals. Mineral commodities for which Africa had a high percentage of world output were bauxite, 16%; chromite, 44.5%; cobalt, 76.5%; copper, 13.9%; diamond, 50.7%; gold, 32.9%; manganese, 27.1 %; phosphate, 22.1 %; platinum-group metals, 48%; uranium, 29.2%; vanadium, 54%; and vermiculite, 41 %. Several of these, chromite, cobalt, diamond, and manganese, were not produced in the United States.

Jan 1, 1992

By Frank D. Lamb

"INTRODUCTION The use of beryllium and its alloys has come into prominence in the last 15 years and increased considerably during the war. In contrast to other light metals, such as aluminum and magnesium, beryllium is relatively hard, has a high melting point (1,285° C.), and other properties that make it resemble steel in many respects. It has a specific gravity of 1.85, is only slightly heavier than magnesium (specific gravity 1.74), and is appreciably lighter than aluminum (specific gravity 2.7). Its lack of ductility prevents its use as a structural material, but this difficulty may be overcome in the future by the use of various alloy forms. The only important commercial alloy in which beryllium is used today is with copper. The addition of small percentages (1/2 to 2 percent) of beryllium to copper imparts properties to the alloy that make it desirable for use in springs carrying electrical current, particularly at high temperature. Many other uses of berylliam are known, and new uses are being found constantly that make the metal of increasing interest.Possibly the main factor preventing the use of more beryllium is the lack of a large source of beryllium ore. Many beryllium minerals are found as minor constituents of natural deposits, some of the more common ones being beryl (Be3Al2(Si03)6), chrysoheryl (Be A1204), helvite (3(Mn, Fe) Be Si04. MnS), and phenacite (Be2Si04). Of the known beryllium minerals, beryl is by far the most common and has been found distributed rather widely throughout the world. It usually occurs associated with granitic rocks and is commonly found as a constituent of granitic pegmatite."

Mar 1, 1947

By B. W. Gandrud

In July 1948, the Bureau of Mines, United States Department of the Interior, in cooperation with the University of Alabama and mine operators, published Report of Investigations 4306, "A Combination Cleaning and Dewatering Process for Treating Fine &apos;Sizes of Coal, Preliminary Report In this report a new process, referred to as kerosene flotation; was described, and results of experimental work with the process Previous to the fall of 1947 were given, The contents of the report. were summarized on pages 19 and 20&apos; as follows: In coal-preparation plants using wet methods of cleaning, the most difficult problem is the cleaning and dewatering of the "fines" from about 10-Mesh to 0. A combination proceed is now under investigation that shows promise of practically and feasibly solving this problem. The process is similar to froth flotation, but a generous quantity of kerosene is used as one of the reagents, and the feed is from approximately 10-mesh to 0 considerably coarser than the usual froth flotation feed. The kerosene and the coarseness of the reed result in a floated product that, under certain circumstances, can be dewatered satisfactorily by a simple process of mechanical squeezing, Squeezing is accomplished by means of an ordinary conveying&apos; Auger-and trough assembly with a section of pipe easing at the outer end of the trough. The bottom of the trough and. casing is fitted with wedge-wire sections to permit escape of the water freed by the squeezing action of the auger. On account of the important role of the kerosene, the process has been referred to in this report as kerosene flotation. Up to now, the investigative work has been divided about evenly between the laboratory and commercial plants. Nearly all of the work has been done on sludges containing the solids from the underflow of dewatering screens. A few runs have been made on 10-mesh to 0: fines from raw coal, but in some of those runs the dewatering mechanism, failed to function.

Jan 1, 1950

By Irving Hartmann, Edward Thomas

"INTRODUCTION Adoption of rubber-tire shuttle cars underground in conjunction with mobile coal-loading machines has introduced new problems in the control of dust on mine roadways. Where this type of loading and transportation is used, development and extraction are generally rapid, with the result that much coal is spilled from the shuttle cars during normal operation, Coal in the roadways from this source and from sloughing of the ribs is ground to fine dust by the wheels of the 'shuttle cars and by the treads of the loading and mining machines. The coal dust usually is somewhat contaminated by pulverized rock, and the mixture could not be loaded with the run-of-mine coal without undue contamination of the product even if it were cleaned up promptly.The presence of large quantities of fine, loose dust, which is constantly stirred up and kept in suspension in air by the traffic, constitutes a grave explosion hazard, reduces visibility along the roadways, and is physiologically harmful to the workmen who breathe the air. From the operating standpoint the loose material is undesirable along the roadways because it provides poor traction for the trucks and thereby increases wear and power consumption. The dust-explosion hazard could be eliminated or reduced by frequent application of sufficient rock dust on the roadbed; but this would not remedy the other difficulties, and in fact it might intensify them. Where practicable, the most direct and effective safety measure is to clean up and remove promptly all dust that forms and settles on the roadways. Unfortunately, in many cases this procedure is not feasible. A third Suggested remedy is to prevent dispersal of the dust into the air and to promote its consolidation on the floor by wetting the dust particles.During the past few years several mines have used calcium chloride on shuttle-car roadways to allay the dust thereon. When exposed to the' humid atmosphere of the mine this salt absorbs Moisture from the air and deliquesces, and in this way wets the dust on the floor of the roadway. In a survey conducted in coal mines in southern West Virginia and in eastern Kentucky where calcium chloride has been in use, somewhat conflicting re- ports were received regarding the merits of the application, and several operators have abandoned the practice either because of actual or assumed disadvantages. The purpose of the study described in this report was to collect and correlate evidence and, on the basis of experimental data obtained in the field and in laboratory tests, to present a clearer picture of the factors involved in the allaying of dust by use of salts."

Sep 1, 1945

By Frederick C. Trutt

Research performed on arcing faults and their interactions with electrical insulating materials within coal-mine power system enclosures are described. This work was performed at The Pennsylvania State University from December 1, 1976 through August 31, 1978. The thrust of this research has been divided into several primary areas. These include the development of a theoretical procedure for computation of three-phase and line-to-line arcing fault currents as a function of time, formulation of arc and tracking models so that arc voltages and energies may be computed, development of a simulation for pressure and temperature rises when a fault interacts with an electrical insulating material within an enclosure, experimental evaluation of electrical insulating materials in terms of their tendency to support and maintain an arc as well as their potential contribution to enclosure pressure rises, and integration of the above research areas to form overall procedures for theoretical and experimental evaluation. During the course of this research, consideration has been given to the possible effects? of an internal methane-air explosion within an enclosure as well as the potential influence of utilization-voltage-level, conductor spacings, and enclosure venting. Conclusions and recommendations address potential means for protection against enclosure failure, internal design considerations, and low-power testing procedures which might be used to evaluate insulating materials to be utilized within an enclosure.

Jan 1, 1978