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By Jerry J. Gray

The utilization of secondary titanium was determined in a study by the Bureau of Mines, and a 10-year statistical table showing supply and distribution patterns is presented in this report. Over the total 10-year period, estimated scrap consumption is larger than estimated scrap supply. Trends from the estimated data indicate that titanium is in short supply and probably will continue to be in the future. Because of higher processing costs for recycle scrap, scrap will tend to migrate to the steel and aluminum industries and to ferrotitanium production and exports. Nonrecoverable losses of titanium metal during processing was determined to be a potential area for research.

Jan 1, 1971

By C. L. Severy

The Reeder No. 1 well was drilled by the Bureau of Mines in cooperation with the Geological Survey as agents for the Defense Plant Corporation. The well is south of Crescent Junction near Thompson, Grand County, Utah. It was started May 5, 1942, and completed August 3, 1942, for the purpose of con-firming the presence of magnesium salts in a deeply buried bed. Drilling was done under contract by the Mack Drilling Co. This report contains an outline of the physical features of the well, a brief history of drilling, and a description of the deposits and occurrences of oil and gas encountered in the drill hole. The work performed by the Bureau of Mines is described in considerable detail, with particular emphasis on drilling procedure and sampling. The report is concluded with a brief description of core-sample preparation for analyses. Appendix A comprises a log of the drill hole, and appendix B is a tabulation of analyses of cores.

Jan 1, 1949

By C. Özgen Karacan

Gamma ray, density, sonic and core logs obtained from two boreholes drilled over a longwall panel in Southwestern (SW) Pennsylvania were analyzed for formation boundaries, log-derived porosities and densities and for rock elastic properties from sonic transit times. Gamma ray (GR) and density logs (DL) were analyzed using univariate statistical techniques and fractal statistics for similarity and ordering of the log data in depth. A Fourier transformation with low-pass filter was used as a noise elimination (filtering) technique from the original logs. Filtered data was tested using basic univariate and fractal statistics, rescaled range (R/S) and power spectrum (PS) analysis to compare the information characteristics of the filtered logs with the original data. The randomness of log data in depth was analyzed for fractional Gaussian noise (fGn) or fractional Brownian motion (fBm) character. A new prediction technique using radial basis function (RBF) networks was developed to calculate shear and Young?s moduli of the formations when sonic logs are not available. For this approach, the filtered logs were used as input to an RBF based upon a combination of supervised and unsupervised learning. The network was trained and tested using rock elastic properties calculated from the sonic log of one of the boreholes. The network was used to predict the elastic and shear moduli of the coal-measure rocks over a longwall coal mine in SW Pennsylvania. This approach demonstrated that it could be used for prediction of elastic and shear moduli of coal-measure rocks with reasonable accuracy.

Jan 1, 2009

By W. E. Pittman

The Bureau of Mines, as part of its Health and Safety Technology Program, is conducting research on the use of ground penetrating radar (GPR) for mine hazard detection. GPR offers a possibility of mapping immediate below-surface geologic conditions, including faulting and other anomalies, thereby exposing potential safety hazards to miners. This report summarizes a literature review of the current status of GPR research in and outside the Bureau.

Jan 1, 1984

By R. W. Van Dolah

An investigation was made of the distances over which sympathetic detonation of ammonium nitrate (AN) and ammonium nitrate-fuel oil (AN-FO) might be expected. Large-scale gap tests used two types of AN-FO donor charges in three sizes with AN, both at ambient and elevated temperatures, and AN-FO acceptor charges. Donor sizes were varied to test the validity of a scaling law commonly used in quantity distance tables. The up-and-down experimental design was chosen to determine the 50-percent initiation point efficiently. The acceptor charges were instrumented to indicate initiation and to determine detonation velocity. Other electronic techniques for measuring the rate of growth, stability of detonation, and detonation pressures were employed. Air shock and fragment velocities between charges were measured by electronic and photographic methods, and determination of side-on air-blast pressures and impulse duration were made for about half the shots. Separation distances between donor and acceptor were found to be larger than anticipated both for the AN and the AN-FO. With AN-FO acceptors and a 16-gage steel faced donor, one initiation occurred at a separation of 53 feet or nearly 16-charge diameters; with AN, initiation occurred at 4 to 5-1/2- charge diameters.

Jan 1, 1966

By Michael Rieber

Commodity transportation by barge is possible on about 25,000 miles of navigable inland waterways in the contiguous 48 states. Barge operations are used chiefly for the movement of bulk raw materials ranging from farm products to iron ore, coal, and other bulky semi-finished as well as finished products such as steel, chemicals and petroleum [3,p.7-9]. The barge industry, unlike other transportation industries, is largely unregulated. This is because all liquid bulk commodities most dry bulk commodities transported by for-hire carriers and companies engaged in private transportation of their own commodities are exempted from Interstate Commerce Commission regulations. As a result, about 15 percent of the total ton-miles of barge traffic each year is under Interstate Commerce Commission regulation [13,p.14-25].

Jan 1, 1977

By Sam S. Taylor

In most oil fields, natural gas is the major source of energy causing flow of oil to the well. The amount of gas produced With the oil generally exceeds actual energy requirements, so that in time the gas reserve of the field becomes seriously depleted and the oil production nest be stimulated by some auxiliary means. One of these is to repressure the oil formation with natural gas; or, where a gas supply is not available, often air is used. Although air is a cheap and convenient repressuring medium, its use sometimes is attended with several disadvantages. First, the return air-gas mixture decreases rapidly in fuel value, often until it can be used no longer as a source of power. At the same time, explosive mixtures may result if recycling is used, causing hazards to life and equipment. Second, some fields experience considerable trouble with the formation of emulsions which become increasingly difficult to treat. Although there is no definite proof that air repressuring always causes these emulsions, many operators are convinced that this is the case.

Jan 1, 1934

By Thomas J. Peters

The Lime Creek study area lies 100 air km east of Boise, and 70 air km northeast of Mountain Home, Idaho. The eastern boundary of the 28,000-hectare, east-west-elongate study area lies 0.2 km west of the 3,077-m-high Smoky Dome. The area is mainly underlain by Cretaceous granitoid rocks of the Idaho batholith. No mineral resources were identified, but two mines and one prospect were found in the study area. At the President and the Last Chance mines, in the southwest corner of the study area, gold mineralization occurs along steeply dipping east-northeast-trending faults and associated quartz veins, and within adjacent Cretaceous granitic rock. The mineralized material is not rich enough to mine underground, and near surface, open-pit-mineable deposit areas could not be identified. The third prospect, the Ventura, is within altered pink granite of probable Tertiary age, but metal concentrations are very low. Geothermal activity was not observed within the study area, but hot springs do occur in the Vicinity. Bedrock observed is only suitable for the most basic high bulk and low end value applications, such as crushed aggregate. Numerous sources for crushed stone occur closer to markets. Alluvial concentrate (placer) samples did not contain free gold, and no substantial alluvial bars were seen; deposits were too small to contain resources.

Jan 1, 1993

By R. E. Morgan

Two sizes of Pennsylvania anthracite were gasified in the new-type Lurgi pressure generator at the Dorsten, Germany, works of the Steinkohlengas, A. G. These tests demonstrated that Chestnut-size anthracite and a Rice-Buckwheat mixture containing 27 and 19 percent ash, respectively, could be gasified satisfactorily at an elevated pressure in a fixed bed with oxygen and steam. These coals were especially prepared to approximate a rough-cleaned coal and a washed and screened product. The operating data obtained from the two tests and materials requirements are summarized. A wide range of reactant ratios could not be tested, nor could optimum operating conditions be determined, as the generator was being used throughout the testing program, employing normal operating practices, to produce gas for the gas grid; and the most economical coal, steam, and oxygen ratios may not have been used. Comparative costs are presented of the raw materials required for producing a high-B.t.u. gas, based on the operational data obtained from these tests and, to some extent, on data extrapolated from laboratory experimentation. A flowsheet of a proposed process for producing a high-B.t.u. gas by Lurgi gasification, followed by methanation, is also included.

Jan 1, 1958

By Errol D. Sehnke

This U.S. Bureau of Mines report provides detailed information on worldwide bauxite production capacity by mine and country, including bauxite substitute materials in countries of the former Soviet Union, The information was compiled from a variety of domestic and international sources and was based on information available to the Bureau through December 31, 1994. Capacity data represent announced installed and planned capacities and do not necessarily reflect a U.S. Bureau of Mines judgment of actual mine operating levels or timing of planned expansions. The year-end capacity is the ?in place? capacity or estimated production capacity, whichever is larger.

Jan 1, 1994

By M. M. Tilman

In a Bureau of Mines investigation to develop lead alloys with improved tensile strength and creep resistance, lead-base alloys containing cadmium and antimony in nominal 1-to-1 atomic ratios were melted in air, cast, and rolled into sheet to 90 percent reduction at temperatures varying from room temperature to 175° C. Tensile testing at room temperature and stress-rupture testing at 900±3° F were conducted on the as-rolled alloys. The best tensile properties were observed in an alloy of Pb-4.2 wt pct Cd-4.5 wt pct Sb which exhibited an average tensile strength of 7,270 psi with 36 percent elongation in 2 inches. An alloy of Pb-5.5 wt pct Cd-6.0 wt pct Sb had 100-hour stress-rupture values of approximately 2,100 psi and 1,000-hour values of approximately 1,700 psi.

Jan 1, 1969

By R. P. Maloney

Since mining operations began in 1900, Government geologists and mining men have periodically recorded the presence of the minerals of mercury and antimony in the extensive gold placer deposits near Flat in the Iditarod district of the Yukon River region, Alaska. No serious effort was made to recover the cinnabar contained in the gold placer gravels, and there is no evidence that veins of cinnabar and stibnite exposed in the placer operations (as reported by the Geological Survey) were ever explored or developed. A large monzonitic intrusive, which is the dominant geologic feature of the immediate area, is believed to be the lode source of the valuable minerals in the placer deposits. In contact with the monzonite are argillite and quartzite, metamorphic products from the Cretaceous shales and sandstones.

Jan 1, 1962

By Russell R. McLellan

As part of an effort to develop new or improved placer mining technology in the Tertiary gold-bearing channel gravel of northern California, the Bureau of Mines conducted investigations at the old Badger Hill placer mine in Nevada County, Calif., to collect data and information regarding drilling and sampling methods and deposit characteristics. Sampling studies involved the collection and processing of 400 tons of large-and small-volume samples from drill holes, underground workings, surface pits, and blasthole rounds. A total of 355 samples averaging 2,296 pounds per sample provided reasonably accurate data for analysis of the gold distribution. These studies indicated that the bulk of the gold is within 40 feet of bedrock in stacked, lenticular zones of cemented gravel that are largely confined to the relatively narrow, meandering course of the deepest portion of the bedrock channel. Drilling studies involved the testing of truck-mounted rotary, buckett and vibratory drills, none of which proved to be a completely versatile tool for sampling quickly and reliably both consolidated and unconsolidated gravel..

Jan 1, 1974

By I. Liebman

Two triggered barrier systems and several extinguishing agents were tested against coal dust explosion propagating in the main entry of the Bureau of Mines Experimental Mine at Bruceton, Pa. One system used a high-pressure cylinder to propel the extinguishant; the second system used pressurized nitro-gas or Halon 1301 (CF3Br) in a low-pressure system to power the disperser. The relative efficiencies of the extinguishants were determined by compar¬ing calculated concentrations of the extinguishant clouds present in the mine during suppressing of the explosions. Results showed the following trend of increasing effectiveness: Purple-K (KHC03)<water<hybrids consisting of foam or water combined with Halon 1301<Halon alone. On a weight basis, water was two to three times as efficient as Purple-K, whereas the hybrids and Halon alone were only marginally superior to water. Maximum efficiency of an extinguishant is attained by high rates of discharge from the barrier and by minimizing the time interval between onset of discharge and flame arrival to that necessary for discharge. Both the high- and low-pressure barrier systems were demonstrated to be capable of suppressing coal dust explosions; however, because of the potential hazard of the former, the low-pressure system is considered to be the most attractive prototype.

Jan 1, 1979

By Arcy, D&apos Banister

The productive potential of the Nation&apos;s principal active and inactive silver mining districts has been evaluated, using 1964 economic conditions and assumed silver prices ranging up to $3 per ounce. On this basis, the United States has an estimated 5 billion ounces of unmined silver, excluding minor byproduct silver in gold deposits. Approximately 3.5 billion ounces are contained in deposits requiring higher silver prices to be economically minable, and about 1.3 billion ounces are in currently operating mines. An analysis of silver consumption trends since 1954 indicates that the free world industrial market will climb to nearly 800 million ounces annually by 1985. U.S. industrial silver consumption has been projected to increase at an annual rate of 4 percent from 1965 to 1985. Average annual increase for the remainder of the free world has been 8.1 percent since 1953; this is expected to level off with an estimated average increase of 5 percent to 1975 and 4 percent from 1976 to 1985. Foreign silver production has, in the past, exceeded consumption, but in 1960 the supply deficit was over 100 million ounces. U.S. production, also traditionally exceeding demand, was suddenly overtaken at the start of World War II. By 1964 the annual deficit, excluding coinage, was over 84 million ounces. World coinage requirements of silver are fast declining and expected to total only 25 million ounces annually by 1985. In fact, coins are already becoming major short-term source of silver to fill the large deficit between industrial demand and current production. The larger, long-term deficit (to 1985, the limit of this study) must be balanced by silver from the hoards and new production from silver deposits. Eventually all of the deficit must be met by new production or silver prices will rise until consumption is greatly curtailed. To balance free world supply and demand, it is estimated that the free world must produce an additional 85 million ounces by 1975 and 375 million ounces by 1985. The estimated proportion expected from U.S. deposits is 17 million ounces by 1975 and 74 million ounces by 1985.

Jan 1, 1969

The general nature of the special constructional features that are required to provide safety from explosion hazards on machines approved as permissible by the Bureau of Mines is fairly well known to mining men who are at all interested in safety. These requirements are outlined in the schedules, under the provisions of which the investigations of such machines are conducted. Also, the method of conducting inspections and. tests of such machines has been described in Bureau of Mines Bulletin 305, Inspection and Testing of Mine Type Electrical Equipment for Permissibility, published in 1929. A more detailed knowledge of the special safety features of a particular machine is often useful and sometimes essential for inspectors, safety engineers, maintenance men, and engineers in selecting machines for a particular application. Three bulletins that give information of this nature have been published by the bureau, viz., Bulletin 313, Permissible Storage-Battery Locomotives and Power Trucks. Bulletin 343, Permissible Coal-Handling Equipment. Bulletin 382, Permissible Coal-Cutting Equipment.

Jan 1, 1937

The general nature of the special constructional features that are required to provide safety from explosion hazards on machines approved as permissible by the Bureau of Mines is fairly well known to mining men who are at all interested in safety. These requirements are outlined in the schedules under the provisions of which the investigations of such machines are conducted. Also, the method of conducting inspections and tests of such machines has been described in Bureau of Mines Bulletin 305, Inspection and Testing of Mine Type Electrical Equipment for Permissibility, published in 1929. A more detailed knowledge of the special safety features of a particular machine is often useful and sometimes essential for inspectors, safety engineers, maintenance men, and engineers in selecting machines for a particular application. Three bulletins that give information of this nature have been-published by the bureau, viz., Bulletin 313, Permissible Storage-Battery Locomotives and Power Trucks. Bulletin 343, Permissible Coal-Handling Equipment. Bulletin 382, Permissible Coal-Cutting Equipment. Report of Investigations 3309, Permissible Electrically Operated Air Compressors, which contains similar information, was issued in August 1936, and a Report of Investigations 3326, Permissible Electrically Operated Room Hoists, was issued in January 1937. Thus, the present paper is the third to give detailed information concerning permissible machines of types not included in bulletins, and covers all the rock-dust distributors approved prior to October 1, 1936.

Jan 1, 1937

By J. J. Wallace

This report describes the initial phase of Bureau of Mines research in the hydraulic mining of bituminous coal. The mining site and equipment are described, and the test procedures and results obtained with a bar-mounted monitor are given. Tests showed that hard Pittsburgh-bed coal can be mined hydraulically from a solid face at water pressures of 4,000 pounds per square inch.4 Coal was penetrated to a depth of 4 feet in 20 seconds with 225 gallons of water per minute coming from a 3/8-inch nozzle at 4,000 pounds per square inch pressure. Some difficulty was encountered in cutting the binders occurring in the coal; it was not possible Lu penetrate directly the overlying draw slate.

Jan 1, 1961

By Roy E. Peterson

The Bureau of Mines conducted bench-scale research to evaluate materials which showed potential as low-cost reductants for use in the ironmaking industry. These materials were lignite, subbituminous coal, coal char, tree trimmings, refuse--derived paperboard, used crankcase oil, and peat. To compare their effectiveness, the materials were tested in the reduction roasting of nonmagnetic taconite and, except for oil and peat, in the reduction of iron oxide pellets to metallized pellets. Reduction was conducted in a 18-cm-diameter, rotary drum, which was externally heated in an electric furnace. Over 92 pct of the iron was magnetically recovered from a nonmagnetic taconite after roasting with any of the reductants, but greater quantities of reductant were required to achieve this when the waste materials were used. The fossil fuels were also more effective for metallizing pellets, although metallizations above 90 pct were also obtained with tree trimmings and refuse paperboard. However, refuse paperboard had to be frequently recharged to the furnace because it depleted rapidly.

Jan 1, 1983

By M. J. Sapko

A moderately scaled apparatus was developed by the Bureau of Mines to determine the fire resistance characteristics of mine conveyor belts and similar type materials. The design of the apparatus was based upon data obtained in full-scale fire tests and features a radiant panel to preheat the belt and a methane-oxygen ribbon burner to ignite the sample under ventilating condi¬tions in a rectangular duct. The test method overcomes the limitations of existing laboratory-scale methods and provides a measure of both ignitability and flammability in quantitative terms. Flame propagation depended upon such variables as air velocity, ignitor heat flux, and belt width and height in the test chamber. Data are presented for nine belt materials and fire resistance ratings are proposed in terms of the flame spread rate, heat release rate, and the critical ignitor heat flux. The ratings discriminate between the fire hazard posed by different fire-resistant belts and tend to be in reasonable agreement with those obtained in full-scale fire tests.

Jan 1, 1981