Search Documents

By Oliver Bowles

In its geologic sense the term marble is applied to rocks consisting of crystallized grains of calcite or dolomite or a mixture of the two. Although limestone has the same chemical composition as marble it differs in that the component particles of calcium or magnesium car- bonates are granular and noncrystalline. In marble the crystals may be intimately intergrown, whereas limestone is an aggregation of unrelated particles cemented together into a solid mass. In its commercial sense the term marble has a much wider applica- tion. As susceptibility to polish is one of its chief commercial assets, all calcareous rocks capable of polish are classed as marbles. Lime- stones that show little crystalline structure may, if they take a good polish, be classed as marbles. Furthermore, serpentine rocks, even if they contain little calcium or magnesium carbonate, are classed as marbles, as they are commercial substitutes of true marbles.

Jan 1, 1916

By Wallace W. Roepke

The Bureau of Mines tested new designs of drag bit cutters with sintered diamond inserts instead of standard tungsten carbide tips. The bits were tested for orthogonal cutting forces, primary dust generation, and incendivity, with a standard plumb-bob type conical cutter (600 included tip angle) as the reference. Preliminary wear and impact-failure testing were also done. The results were mixed. Two new designs had forces similar to those of the reference bit, but one new design had about twice the normal force. This same design had almost twice the specific energy during shallow cutting but generated an equal or slightly lower amount of primary dust than did the reference bit. Incendivity was eliminated for two radial designs. One conical design had ignition only after more than 15 impacts, but the other conical design was incendive. Impact failure occurred, but not so quickly as anticipated. Over 7,500 impacts on a sandstone face, with a total cutting distance of more than 1,981.2 m, only scuffed the leading edge of the sintered diamond cutting face but put hairline cracks in the substrate mounting pad. Additional design and testing are needed to develop an optimum cutter, but prospects look good for this material.

Jan 1, 1983

By Jr. Reistle

The tests reported in this paper were made in the East Texas field in the summer and fall of 1932 as a part of the Bureau of Mines study of the operation of flowing wells and reservoir performance; and to determine, if possible, the minimum reservoir pressure necessary to produce the wells in this field by natural flow through different sizes of flow strings. The minimum reservoir pressure that would be required to Maintain natural flow through 2 1/2-inch tubing was determined experimentally for the existing energy conditions in the East Texas field. With the present available data, however, it is impossible to predict accurately or to determine by calculation the necessary energy requirements for maintaining the vertical flow of oil and gas mixtures under all conditions. Although some valuable data were obtained which seem to have application to the solution of problems involving vertical flow, this important research of the petroleum industry is so involved that more study of the complicating factors influencing the flow of oil-gas mixtures through vertical pipes is required.

Jan 1, 1933

By C. T. Baroch

The purpose of this report is to describe the design features and techniques used in operating a plant capable of producing about 1,500 pounds of titanium metal per day. The process used was based on the reduction of titanium tetrachloride with magnesium, a modification of what is generally known and spoken of as the Kroll process. Sponge metal crushed to melter's specifications was the end product of the operation as conducted. The report is divided into sections covering general plant layout and the major unit operations. These, in turn, are each divided into discussions of the equipment, operating procedures, and typical results. Descriptions are given in more detail than is generally expected of a technical report. During 1953 and 1954 over 130 engineers and businessmen, officially representing some 80 industrial, chemical, end engineering firms, visited the operating plant, and their questions, which indicated a serious interest in details, have served as a guide for the material contained in this report.

Jan 1, 1955

By C. J. Wilhelm

The disposal of brines produced with crude petroleum and natural gas has been a long-continuing problem to oil and gas operators as well as to farmers and stock-raisers in the vicinity of producing fields. An impartial appraisal of conditions pertaining to the problem of brine disposal leads to the conclusion that study of the technical consideration, with proper weight given to the economic and social factors, is the most desirable approach to this problem. Brine disposal is a problem of such magnitude in certain areas in the State of Kansas that in August 1934 a cooperative agreement was made between the Kansas State Board of Health and the U. S. Bureau of Mines for a cooperative technical study of methods of brine disposal.

Jan 1, 1935

By P. B. Altringer

Searles Lake, CA, contains the largest known domestic tungsten resource. The brines in this near-dry lake bed, located in the Mojave Desert 130 mi northeast of Los Angeles, contain an estimated 135 MMlb of tungsten. However, the low concentration of tungsten (0.080 g/L W03) in the supersaturated brine makes selective tungsten extraction very difficult. Although many brine chemicals are extracted from the lake, tungsten recovery was an elusive goal prior to Bureau of Mines development of an ion-exchange technique. This publication describes the Bureau process. The following subjects are ad-dressed: ? The Searles Lake tungsten resource. ? General problems associated with tungsten recovery. ? Bureau research objectives. ? Synthesis of ion-exchange resins. ? Development of a two-stage ion-exchange tungsten extraction and concentration procedure. ? Product recovery and purification. ? Economic evaluation. Flowsheets for recovering three products (calcium tungstate, sodium tungstate, and tungstic oxide) are presented and evaluated, as well as a summary of the research effort and potential applications.

Jan 1, 1985

By C. Melvin Lepper

Microseismic energy is generated when stresses accumulated in rock formations are released in the form of fracturing. The acoustic emissions resulting from these rock fractures and movements are detectable as velocity signals in the earth near the energy source. A Bureau of Mines microseismic system that is capable of detecting the acoustic emissions from pit slope movements is described. The digital circuitry incorporated in the system allows a microprocessor program to immediately calculate and present the location coordinates for the seismic energy source in the mine pit wall. This monitoring system is compact, portable, reliable, and relatively inexpensive and rapidly provides accurate information to the mine operators about the stability of a pit slope.

Jan 1, 1982

By C. J. Wilhelm

The disposal of brines produced with crude petroleum and natural gas has been a long-continuing problem to oil and gas operators as well as to farmers and stock-raisers in the vicinity of producing fields. .An impartial appraisal of conditions pertaining to the problem of brine disposal lead to the conclusion that study of the technical considerations, with proper weight given to the economic and social factors, is the most desirable approach to this problem . Brine disposal is a problem of such magnitude 1n certain areas in the State of Kansas that in August 1934 a cooperative agreement w s made between the Kansas State Board of Health and the U. S. Bureau of Mines for a cooperative technical study of methods of brine disposal.

Jan 1, 1935

By A. R. Rule

A flotation process was developed by the Bureau of Mines for separation of carbonate and phosphate minerals occurring in unaltered phosphate ores of the Phosphoria formation. The process involves depression of phosphate minerals with fluosilicic acid and flotation of carbonate minerals with fatty acid emulsions. In individual laboratory tests, selective removal of carbonates was achieved with phosphate recoveries ranging from 60 to 80 pct P205. In continuous-circuit testing, sizing and separate treatment of coarse and fine fractions was necessary to achieve 65-pct P205 recovery. Concentrate grade ranged from 26 to 33 pct P205. The flotation tailings containing primarily carbonate and phosphate minerals is a potential fertilizer material. When reacted with H3P04, concentrated superphosphate containing approximately 40 pct available P205 was obtained.

Jan 1, 1974

By W. C. Holliman

This report on the characteristics of commercial aviation gasolines presents compilations of inspection test data furnished on their products by manufacturers of commercial grades of aviation gasoline, and special data obtained in Bureau of Mines laboratories on samples of these gasolines. Data and physical samples for the survey were submitted by 15 manufacturers on 18 grade 80, 21 grade 91/98, 22 grade 100/130, and 10 grade 115/145 aviation fuels.

Jan 1, 1948

By David R. Peterson

This report presents a deep ocean mining operational simulation which is capable of describing the response of the bottom collection unit to specified mining ship maneuvers and the corresponding operation of the mining ship maneuvering system. Bathymetry, obstacles, collector and pipe dynamics and ship maneuvering capabilities are included in the simulation. The simulation is capable of evaluating the technical requirements and operating costs for specified mine plans, Results are useful in assessing mine size requirements and provide operating 'cost 'estimates useful as inputs to deep ocean mining economic feasibility assessments, The simulation is used to determine the consequences of obstacles to mining system operations in terms of impact on mine size requirements and reduced production arising from obstacle avoidance maneuvers of a towed (unsteered) collector.

Jan 1, 1979

By Robert E. Barieau

A list of 163 references to original experimental PVT data on helium is presented for the period 1895 to 1968. The list is complete as of the start of the Helium Centennial Year, 1968, to the best of the author's knowledge. Citations were keypunched for easy updating and are listed alphabetically by author.

Jan 1, 1968

By Frank C. Townsend

Waste disposal schemes using spent shale in embankments require a thorough knowledge of its geotechnical engineering properties for environ-mentally safe disposal. In this context, the objective of this laboratory investigation was to determine the physical properties, geotechnical properties, and composition of spent oil shale retorted by the PARAHO and TOSCO processes. Physical properties consisted of mechanical analyses, Atterberg limits, and specific gravity determinations. Geotechnical engineering properties were determined by compaction, maximum-minimum density, unconfined compression, triaxial compression, permeability, direct shear, Ko, cyclic tri-axial, resonant column, and Los Angeles Abrasion tests. Petrographic, chemical, and scanning electron microscopy analyses were used to determine compositional features. Unprocessed shale is hard and durable and more properly described as a carbonate rock instead of shale. PARAHO is classified as a GP, while TOSCO classifies as an SM. PARAHO requires no moisture for compaction to maximum densities; however, TOSCO does. Retorting causes a loss in durability but creates self-cementing characteristics, which for PARAHO a 3-to 8-fold strength increase was observed, while for TOSCO the increase was 1.5 to 3 folds. The shear strength, compressibility, and dynamic properties of compacted PARAHO are comparable to those for sandy gravels. Compacted PARAHO is semipervious, while compacted TOSCO can be semipervious to impermeable.

Jan 1, 1979

By F. E. Cash

The Holmes Safety Association was organized and named in honor of the late Dr. Joseph A. Holmes, first director of the United States Bureau of Mines. The association is a national organization and operates through local, sectional, or State chapters in mining, petroleum, and allied industries. The National Council of the Holmes Safety Association consists of representatives of State councils and local chapters, with the Director of the Bureau of Mines as president.

Jan 1, 1929

By Wils L. Cooley

Several aspects of mine safety grounding systems and equipment are studied. Electrolytic corrosion of test ground beds has shown a high incidence of stray current damage, while efforts to build a reliable continuous ground bed monitor continue. Laboratory and field investigations of trailing cable splices have yielded strong evidence that splices can contribute to stray current problems in the mines, but a method is suggested for discovering deteriorating splices before they pose a serious hazard. A prototype device has been constructed to evaluate the electrical resistance of rail bonds underground as a source of stray current. Theoretical modeling of ground electrodes, has advanced considerably, now covering measurements of large cylindrical electrodes, multiple-rod ground beds, rod electrodes in stratified earth, and measurement of connected beds. A prototype instrument design is given for a potential gradient plotter to quickly evaluate voltage gradients near earth electrodes. Additional ground-check monitor testing is reported.

Jan 1, 1977

By J. O. Lewis

In its efforts to reduce waste, and increase efficiencyin oil production, the Bureau of Mines is investigating methods of increasing the recovery from the underground sources of supply, which are the foundation of the petroleum industry and the many allied industries wholly or partly dependent on it. In the face of a demand that is increasing faster than the production and that, in the consensus of opinions of well-informed authorities, is soon likely to outstrip the productive capacity, it is well to consider whether it is not possible to extract more oil from the known sources of supply. It is universally acknowledged that by the usual production methods much oil is left underground, the general opinion being that at least 50 per cent of the oil in a field remains unrecovered when the field is abandoned as exhausted. From the writer's own investigations he believes the average recovery is even less, and if any considerable portion of this oil being left underground could he made available it would have a tremendously favorable influence on the petroleum industry and all the industries dependent on it. In this publication are considered the principles involved in increasing recovery and methods of extracting more oil from the oilbearing formations than by the usual ways of producing. These methods are: The use of gas or vacuum pumps, forcing compressed air or gas through the oil-bearing formations, displacing the oil by water, and better utilization of the natural pressures in the oilhearing formations. Especial attention is being given to a processcommonly known as the Smith-Dunn-for forcing compressed air through oil-bearing formations because it is believed to hold most promise for the future.

Jan 1, 1917

By Allan E. Martin, George Glocker, C. E. Wood

"INTRODUCTION As part of a comprehensive investigation of the mechanism of defurization of iron and steel by slags, the Blast Furnace Studies Section, Metallurgical Division, Bureau of Mines, in cooperation with the Institute of Technology, University of Minnesota, has made a study of the forms in which sulfur occurs in blast-furnace slag. This report presents data on the three sulfides most important in iron smelting, namely, ferrous sulfide, manganous sulfide, and calcium sulfide. The tendency of these sulfides to form colloids in the molten slag was determined by an examination of quenched samples with an ultramicroscope.Vogt/ conducted experiments on sulfide silicate melts and examined synthetic blast-furnace slags in a partly crystallized condition. His conclusions were that FeS, CaS, and MnS, or isomorphous compounds, such as (FexCay)S and (MnxCaa)S, were precipitated from the melt, depending on the composition of the slag. In all specimens sulfides were visible and were spherical.Coloration of glass by sulfur also provides indirect information on the nature of sulfur in blast-furnace slags./ There seems to be a general agreement at present among the workers in the field of colored glasses that ferrous sulfide is a strong color producer. Colors that have been attributed to this compound include yellow, orange, brown, blue, and black. Apparently the ferrous sulfide is considered to be dissolved in these glasses. There is no indication that any of them have been examined for a colloidal phase.Lorenz 7/ investigated a single manganese slag in the glassy state and observed a Tyndall beam in an ultramicroscope. His conclusion was that either a manganese compound had precipitated in a finely divided condition or that metallic manganese had volatilized and penetrated into the slag as a vapor and thus formed colloidal particles."

Feb 1, 1941

By J. Cooperman

THE INVESTIGATION was carried out in three stages, depending on the objectives of the work and the kind of equipment used. The first stage involved testing of 11 representative Alabama coals, the source of which is given in table 1. The objective was to find whether these coals could be gasified raw by the Lurgi method, and the equipment used was a 4-inch batch generator (to be described later). This generator proved too small and difficult to control to provide adequate amounts of products under continuous operating conditions for testing. For the second stage, a 6-inch batch generator was used, which was provided with facilities for superheating the steam-oxygen mixture and for synthesizing additional methane from the residual carbon monoxide and hydrogen in the primary Lurgi gas. Selected Alabama coals, Pittsburgh-bed coal from West Virginia, "Disco," and anthracite were used. For the third stage of the work, a continuous generator of 1 square foot grate area, following closely the design of the industrial generators operated in Germany, was provided. This generator was designed by 0. Hubmann, engineer for the Lurgi company, and was expected to give results closely simulating industrial-scale apparatus. The purpose of this equipment was to test prepared materials shown to operate smoothly in the 6-inch generator under conditions approximating as nearly as possible those prevailing in industrial practice. Work of the first stage showed that Alabama coals could not be used in the Lurgi process without first destroying the coking power.

Jan 1, 1951

By Ferdinand Roehlich

An evaluation of the use of manually activated, installed,. dry chemical fire protection systems on underground metal and nonmetal mine vehicles is described. In addition, an assessment of the possible health risks posed by the dry chemical extinguishing agents used in such systems is provided. Work involved installation of fire protection hardware on an operating piece of underground metal/nonmetal mine equipment and, via actual fire tests, a determination of the effectiveness of the hardware in extinguishing on-vehicle fires. Two fire protection systems were installed on a Caterpillar 988 front-end loader in St. Joe Mineral's Fletcher mine, near Viburnum, Mo. Both a fully pressurized Safety First CM-20 and a nonpressurized cartridge actuated Ansul A-101 were installed for comparative purposes. Both systems operated satisfactorily during an 8-month endurance trial period which preceded the actual fire tests. Each system was able to extinguish an 18" x 4" class B test fire placed in the engine area of the machine. The health hazards analysis of dry chemical powder consisted of a detailed search of published literature relating to these multipurpose agents. This data was verified via a controlled laboratory analysis of two monoammonium phosphate based powders (Safety First Unikem and Ansul Forey) and an analysis of air samples collected at various locations on the test vehicle during the fire tests. Although the powder was found to be nontoxic, two potentially dangerous thermal decomposition products were identified--ammonia and phosphoric acid. However, later analysis indicated that an operator would not be exposed to dangerous concentrations of either compound if he were to remain outside of the powder cloud. A "Selection and Use Manual for Manually Activated, Fixed Fire Suppression Systems on Underground Metal and Nonmetal Mining Equipment" was prepared both as an, appendix to the report and for distribution under separate cover.

Jan 1, 1977

By J. A. Kost

A survey of 80 coal producers was conducted to determine the extent and scope of respirable dust control research for underground coal mines and the current methods employed to control respirable dust. Results of the survey showed that proper face ventilation and an adequate water spray system are sufficient to comply with mandatory standards in room and pillar mining. Difficulties still exist with longwall equipment, auger miners and buring machines. In these cases, known dust control techniques are not sufficient to obtain compliance. Present state-of-the-art face ventilation and water systems were discussed in addition to the sampling program.

Jan 1, 1980