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By Felix duBreuil

The present sampling procedure for evaluating the rock dusting conditions in a coal mine is time consuming. This study considers means by which this procedure could be simplified. Surveys were conducted in six coal mines in Pennsylvania to determine the in¬combustible content of the deposited dust. Some 2,000 samples were analyzed and statistically evaluated. It is suggested that the mean incombustible content could be obtained with fewer samples and smaller samples without greatly increasing the sampling error.

Jan 1, 1972

By Khamis Y. Haramy

This U.S. Bureau of Mines report describes the use of Bureau-developed flat and cylindrical hydraulic borehole pressure cells. A brief description of the fabrication, installation, and pressurizing equipment is given and pressurizing procedures are discussed. Theories available on evaluation of data from the flat and cylindrical pressure cells and examples of data analysis and stress evaluation are also presented.

Jan 1, 1991

By W. H. Eddy

The Bureau of Mines used several laboratory batch flotation schemes combined with magnetic separation to investigate the feasibility of recovering potash feldspar and glass sands from molybdenite tailings. Four molybdenite tailings or prospective tailings were used as test samples. Feldspar concentrates containing from 10.7 pct to 12.0 pct K2O were recovered from three of the four samples. The alkali content of the fourth sample met the grade for a mixed feldspar. All the feldspar concentrates contained iron in excess of the 0.10-pct-Fe203 specification for most uses. Electron-beam microprobe examination of the feldspar concentrates showed the presence of an iron-bearing potash feldspar in quantities that were excessive with respect to most iron specifications. However, a high-quality glass sand was produced from all of the samples.

Jan 1, 1980

By David L. Bickel

Stress-relief techniques and instrumentation have been developed through many years of research in the Bureau of Mines and successfully used to determine the in situ state of stress in rock. This report describes the Bureau's three-component borehole deformation gauge and the drilling equipment and accessories used with it. Operation and calibration procedures for the deformation gauge are discussed in detail, along with site selection and overcoring procedures. Information and references included in this publication provide a guide to the Bureau's cover-coring method for determining rock stress.

Jan 1, 1985

By Norma R. Golumsic

Gasoline and other liquid fuels may be obtained from coal by direct and indirect hydrogenation.3/ The direct process, usually termed the coal-hydro-genation or the Bergius process, was patented in Germany by F. Bergius in 1914 and developed to a commercial stage by the inventor and I. G. Farben-industrie. From a chemical point of view, the coal-hydrogenation process consists of adding hydrogen to the complex coal molecules and removing oxygen so that its chemical constitution is changed to that of petroleum, whereupon the coal substance liquefies, yielding an aromatic crude oil. In the indirect-hydrogenation process, known as the Fischer-Tropsch process (invented by Franz Fischer and Hans Tropsch in Germany), coal, lignite, or natural gas is first converted to water gas, a mixture of carbon monoxide and hydrogen. This mixture of gases, in proper proportion and after suitable purification, is then passed over a solid catalyst at relatively low pressures (1 to 20 atmospheres) and temperatures ranging from 180° to 260° C. The products obtained are gasoline, Diesel oil, liquefiable gases, and paraffin wax.

Jan 1, 1946

The realization that there is a limit to our supply of domestic mineral and fuel resources, which have been taken for granted until recently, has stimulated the need for conservation and optimum utilization of the Nation's minerals, metals, and fuels-resources critical to our national economy. The mission of the Bureau of Mines is to develop new technology, improve existing technology, and disseminate information related to mineral resources and industries. Fulfilling the mission is necessary to insure a continuing, adequate supply of minerals and alternative supplies of energy from reliable sources at the lowest possible cost to society and the environment. Established in 1910, the Bureau of Mines under the Department of the Interior is the Federal Government's primary research arm in the mineral field. Since the transfer of the fossil fuels portion of the energy research program to the newly organized Energy Research and Development Administration (ERDA) in fiscal year 1975, Bureau research has been concentrated on increasing mineral production, decreasing energy usage through more efficient processing, and decreasing material losses caused by corrosion. Concurrently, research is being addressed to improved coal-preparation techniques, especially to expanding utilization of low-grade coals and coals difficult to beneficiate, which are essential for reducing the need for petroleum and natural gas supplies and for redirecting our energy consumption. Fluctuations in the availability of foreign sources of minerals, metals, and fuels due to political and economic variability among nations have necessitated intensified investigation into coal mining, uranium-ore processing, and geothermal energy sources-three alternatives that can help to alleviate the dependence of the United States on foreign sources of energy.

Jan 1, 1975

By A. L. Engel

In previous reports5/ of ore-testing studies, teats made by established methods on typical ores selected as representative of certain mining districts have been described in considerable detail. In addition to established test procedures, such as screen analysis, Chemical analyses, microscopical examination of ores and products, sink-and-float separation, gravity concentration, floatation, and magnetic separation with or without roasting, it was sometimes necessary to apply other methods, such as leaching, in instances where physical separations were not feasible.

Jan 1, 1940

By A. L. Engel

In previous reports5/ of ore-testing studies, tests made by established methods on typical ores selected as representative of certain mining districts have been described in considerable detail. In addition to established test procedures, such as screen analysis, chemical analysis, microscopical examination of ores and products, sink-and- float separation, gravity concentration, flotation, ,and magnetic separation with or without roasting, it was sometimes necessary to apply other methods, such as leaching, in instances where physical separations were not feasible.

Jan 1, 1940

By David Schlain

A small alumina reduction cell with a graphite crucible and boron nitride liner was developed by the Bureau of Mines as the initial phase of a study of the reactions which occur in the reduction of alumina by the Hall-Heroult process. Operating conditions in the cell such as temperature, time, current density, electrolyte composition, and electrode materials may be varied easily. Aluminum was produced in the cell at a current efficiency of about 75 percent and a cell voltage of 2.7 volts. Although the data are not wholly conclusive, the operation of the cell did not appear to be greatly affected by large changes in temperature, electrode spacing, current density, and alumina concentration in the electrolyte.

Jan 1, 1963

By N. E. Hanna

As part of a program for improving, the safety of permissible explosives, the Federal Bureau of Mines has undertaken an investigation to establish the ability of sodium chloride to reduce the incendivity of permissible explosives to firedamp atmospheres. A motivating influence for this investigation has been the comparatively extensive experience of British and other European investigators, who used sodium chloride as a component of their permitted explosives (1, 5, 6 7).5/ In the United States research and development work of this type has been less extensive, although sodium chloride has been added to permissible explosives as a cooling agent (9) for many years. The results of the first phase of this investigation were presented in a previous paper (8), which established that adding up to 10 percent sodium chloride to permissible explosives reduces the likelihood of ignition of firedamp in the gallery test; however, the results were somewhat inconsistent, and the conclusions were qualified. Accordingly, the investigation was continued with a study of the effect of added sodium chloride as a function of the quantity added and of the particle size of the salt.

Jan 1, 1960

By G. R. Hopkins, E. M. SEELEY

According to reports received by the Bureau of Mines, Department of Commerce, as of Jamary 1, 1930, there were 1,035 natural-gasoline plants in the United States, with a total daily capacity of 10,516,000 gallons. (These data do not include one small plant in Alaska.) The last similar survey, that of Jamary 1, 1928, showed a total of 1,155 plants of 8,048,000 gallons daily capa- city. This in two years time the number of plants has decreased by 120, but the total capacity has increased 2,468,000 gallons or 31 per cent. This is roughly equivalent to the gain in production over the same periodi Over half of the increase in total capacity was registered in California, where the development of flush oil production having a comparatively high gas-oil ratio in such fields as Santa Fe Springs led to construction of some new plants and material enlargement of others. Of the total plants, 999 were operating on Jamary 1, 1930, and 36 were shut down. This compares with 1,060 operating and 95 shut down two years ago, which indicates a tendency to dismantle plants as soon as they become obsolete or umrofitable. The total daily capacity of the plants operating on Jamiary 1, 1930, amounted to 10,278,000 gallons, or 98 per cent of the total, leaving only 238,000 gallons, or 2 per cent, for the shut-down plants. This contrasts with the refining industry, which usually has 5 per cent of its total capacity idle; the difference is due to the relative ease with which a refiner can secure a crude supply as against the difficulty the natural gasoline manufacturer has in reestablishing his gas connections. During 1929 the average total daily capacity of the operating plants was 9,899,000 gallons, while the average daily production amounted to 6,015,000 gallons. This indicates that the plants operated during 1929 at 61 per cent of their capacity. Although over 60 plants were dismantled in Oklahoma during 1929 the State continued to rank first in total mumber. California was second in mumber of plants with 165, and was one of the few States that showed a gain since the

Jul 1, 1930

By C. N. Adams

The purpose of this investigation was to evaluate the physical and mechanical properties of high-purity titanium made by two processes. Sodium-reduced metal with 58 Brinell hardness number (B.h.n.) and electrorefined metal with 60 B.h.n. and 70 B.h.n. were used. Titanium of these hardness levels did not work-harden excessively, and beyond 40 percent cold work the hardening effect was not great. Rapid softening occurred when the metal was annealed at temperature between 300° and 600° C. Full annealing, as determined by property and microstructure studies, was accomplished after 30 minutes at 700° C. A recrystallization diagram is presented which is based on determinations of annealed grain size as a function of rolling reduction and annealing time. For reductions of less than 20 percent, exaggerated grain growth occurred during annealing; for reductions greater than 20 percent, the variation in grain size for each annealing temperature was minor.

Jan 1, 1961

By J. H. Tylczak

The Bureau of Mines studied the effect of alloy additions on abrasive wear of low-alloy steels. A dry-sand, rubber-wheel abrasion test appa-ratus using ASTM G65-Sl procedure B was used for the abrasive wear tests. Eighty-six material heat-treatment combinations were abrasion tested. Results of these tests were analyzed statistically using regression analysis to see if additions of Cr, Mn, Mo, Ni, Si, AI, Cu, and S were significant in affecting the abrasive wear rate of low-alloy steels. Regression analysis was also used to confirm hardness and C affect on the abrasive wear rate of these steels. It was found that for all the steels taken as a group, increased amounts of Mn significantly reduced the wear rate, while increased amounts of Mo and S1 increased the wear rate. Analysis also confirmed previous research done by others, that increasing hardness and amounts of C reduced the wear rate. For the hardened steels taken as a class, only increasing amounts of C and Mn reduced the wear rate, while increases in Si increased the wear rate. In the class of unhardened steels, increases in C, Mn, and S re-duced the wear rate, whereas increases in Mo increased the wear rate. The steels with the best resistance to wear were two hardened experimen-tal steels similar to AISI 1055 and AISI 107S.

Jan 1, 1986

By D. C. Dahlin

The U.S. Bureau of Mines investigated the magnetic susceptibility of minerals as a function of mag-netic field strength to determine how it might affect the potential for high-field magnetic separation as an alternative to other separation technologies. Single-mineral concentrates were prepared from specimens from the same deposit to compare magnetic susceptibilities of minerals that occur together and from specimens from different deposits to compare magnetic susceptibilities of like minerals. A vibrating-sample magnetometer with a superconducting magnet capable of producing a magnetic field of 7.16 x 106 Aim (90 kOe) was used to measure the magnetic moment of the samples. The data were then converted to specific magnetic susceptibility data and plotted as a function of magnetic field strength. Cursory studies were also completed on the effects of iron content and oxidation roasts on magnetic susceptibility in high fields. The results showed that magnetic susceptibility is essentially constant in magnetic fields above those needed to saturate ferromagnetic constituents. Although magnetic susceptibility is influenced by iron content and by thermal treatment, the changes are not large enough to influence separations in fields above 1.59 x 106 Aim (20 kOe).

Jan 1, 2010

By R. C. Hickman

"INTRODUCTION Marl, consisting of a bed of coarse shell conglomerate from 1 to 5 feet thick, occurs on the Chesapeake Corporation tract and Philbates properties in New Kent County, Va.Nine holes were drilled on these properties in February 1946. ACKNOWLEDGMENTSIn its program of exploration of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts prelimi¬nary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, Oliver C. Ralston, chief, analyzes samples and performs beneficiation tests.The project was under the immediate supervision of Mitchell H. Kline, chief, Raleigh Division, Mining Branch.LOCATIONThe Chesapeake Corp. deposit is reached from West Point, Va., by driving west on State Route 33 to the junction of State Route 634, approximately 5 miles. Proceed southeast along State Route 634 about three-quarters of a mile, at which point an old longing road turns north along a ridge and leads to the marl outcrops about one-half mile distant. The Philbates property lies three-quarters of a mile farther west along State Route 33 from the junction with State Route 634. The property lies north of State Route 33 and east of State Route 623 (fig. 1). The marl deposits are on the north end of the farm. The Chesapeake Corp. tract comprises 174 acres and the Philbato property 58 acres."

Aug 1, 1947

By D. Harrington

Most of those in the Health and Safety Branch, Bureau of Mines, necessarily participate in activities associated with essentially all phases of the mineral industries, including coal and noncoal mines, quarries, smelters, metallurgical plants, and various petroleum operations. One of the strictly war activities of the branch - the Explosives Control Division, which administers the Federal Explosives Act of December 26, 1941 - has functions that require contacts not only with nearly all phases of the mining and allied industries but also with those engaged in scores of other occupations that manufacture, store, use, or possess explosives, or many of the ingredients of explosives. The field men of the Health and Safety Branch (approximately 300 in number) Are occupied full time in health and safety activities and annually make thousands of contacts with people in the mineral industries as well as the plants in which they work. From these they formulate several thousand written reports containing sources of thousands of conclusions and recommendations aimed at reduction of health end safety hazards in these industries. Although such activities have been greatly increased during the war and immediate pro-war periods, they have been in effect to a considerable extent since the Bureau of Mines was created in 1910.

Jan 1, 1944

By John C. Machisak

THIS INFORMATION CIRCULAR covers the calendar year 1055 and contains statistical data on employment and injuries pertinent to metal and nonmetal mining and to their mills and processing plants that are voluntarily reported annually to the Federal Bureau of Mmes. This report, unlike previous publications, lists not only production and development workers but also office employees associated with mining and milling or processing. The last publication m the series, Information Circular 7798, Injury Experience in the Metal and Nonmetal Industries, 1954, also contains unpublished injury and employment statistics for 1943 through 1953. The Bureau is authorized to request data on injuries and employment from operators in the metal- and nonmetal-mining industries. The information voluntarily submitted by these operators contributes immeasurably to the promotion of safety in the mineral mining industries as it discloses the hazards to which metal and nonmetal workers are continually exposed during mineral extractive operations.

Jan 1, 1959

By Richard A. Dick

In this report commercial blasting compounds are classified according to their nitroglycerin (or equivalent explosive oil) and ammonium nitrate content as dynamites, gelatins, blasting agents, military explosives, and blasting , accessories. The ingredients and more significant properties of each explosive are tabulated and briefly discussed. Data are summarized from various handbooks, textbooks, and manufacturers' technical data sheets, together with the author's personal experience; however, this report is not intended to be a technical handbook, since it does not deal with blasting techniques. Instead, it seeks to acquaint the reader with the great variety of explosives, available, their advantages and disadvantages, and their general areas of application. Properties discussed are weight strength, cartridge strength, detonation velocity, density, detonation pressure, water resistance, and fume class. The weakness of the strength rating system and the importance of detonation pres- , sure, density, and detonation velocity in rating explosives are discussed. The terms "blasting agent" and "slurry," which are often misused, are defined. Trends indicate that blasting agents (that is, blasting mixtures with none of of the ingredients singly classified as an explosive), particularly high-density slurry blasting agents, will dominate the explosives field in the future.

Jan 1, 1968

By Robert L. Davidoff

Growing domestic and global demands for mineral resources have established an imperative need for developing comprehensive, versatile mineral supply analysis evaluation tools. The Minerals Availability System (MAS) of the Bureau of Mines is meeting this need with its computerized Supply Analysis Model (SAM). This paper describes the SAM system and the quantitative methods used by the MAS for mineral supply analyses. The MAS evaluating process consists of deposit identification, tonnage and grade determinations, engineering and cost evaluations, financial analyses, and supply curve generation. MAS has developed this computerized system primarily to facilitate the maintenance of data information for the constructing of commodity supply curves. The SAM system presently has the analytical capabilities of simultaneously (I) evaluating many mineral deposits, (2) updating mineral supply information to reflect inflationary changes in costs and prices, and (3) conducting sensitivity analysis to determine impacts on mineral supply under various conditions. Many potential users in both government and industry will find the SAM system a valuable tool for policy analysis, forecasting, and planning. The SAM system has been constructed so that any types of information that are similar to the data elements in the MAS data base may be used to perform supply studies. The storage space needed for the SAM system?s programs, files, and output data is approximately 14 million characters.

Jan 1, 1980

By J. P. Powell

Records show that systematic water flooding was begun as early as 1935 in Greenwood County and in 1937 in Butler County. Water flooding on some earlier projects in Greenwood County were described in a Bureau of Mines Report of Investigation.2/ This report presents a discussion of 4 projects -2 in Butler County, 1 in Greenwood County, and 1 in Butler and Greenwood Counties. The location of these projects is shown in figure 1. The projects have been in operation 6 to 12 years and have recovered about 6.6 million barrels of additional oil from the injection of 84.7 million barrels of water. Three of the projects take advantage of the elevation of the nearby hilly terrain, and water from the treating ponds flows by gravity through the filters into the clear-water tanks. By utilizing gravity flow, fewer pumps and less electrical energy is required, resulting in more economical operation.

Jan 1, 1956