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By Rexford D. Singer

The purpose of this study was to evaluate the current literature on the use of calcium chloride and ligninsulfonates as dust suppressants with respect to potential adverse effects on health or the environment. Calcium chloride poses little internal hazard to man and animals, but toxicity to vegetation in and around the area of application should be expected. The effects, however, should be considerably less than those observed from using calcium chloride as a road deicer. Except for trout, ligninsulfonates seem to pose little direct systemic toxicity problems in aquatic organisms, animals and man or any problem with local vegetation. Because of a greater volume of information on its use and effects, calcium chloride is recommended over ligninsulfonates.

Jan 1, 1982

By J. L. Potter

An inert-gas fusion technique was applied by the Bureau of Mines to the oxygen analysis of mixed-fluoride electrolytes used in electrowinning uranium and the rare-earth metals. Method development included: (1) Thermodynamic and experimental evaluation of the temperature required to quantitatively remove oxygen from a fluoride melt; (2) installation of a water and an acid trap to entrain the volatilized fluorides; (3) development of a suitable sample-preparation technique for the heterogeneous fluoride baths in which both pulverizing and pelletizing were necessary to achieve reproducible results; (4) comparison of platinum flux and dry crucible techniques, which showed that the use of platinum was not necessary. The accuracy of the method was evaluated by analyzing fluoride baths containing known amounts of oxygen added as the metal oxide. In the 0.05-to 0.5-percent range, the relative error was about ±5 percent.

Jan 1, 1962

By Ronald J. Mathis

The objective of this contract is to design, build, surface test, and evaluate a breadboard prototype of the Variable Wall Mining System so that data are available for the design of a production machine. The Variable Wall Mining System (VWMS) consists of a series of side cutting augers, connected end to end, and distributed across a panel. Supplying rotary power at the end of the string and anchorage from conventional longwall roof supports, the augers are sequentially thrust into the face and then lifted to the roof to extract the coal in a continuous manner. The augers not only cut but also transport the coal. The effort described in this report summarizes the operation characteristics of the VWMS, the design methodology used to develop various working models, the surface testing of a ½ -scale version of the VWMS, prediction of power requirements and performance potential of a full-scale system, and a critique of the VWMS concept, conclusions, and recommendations.

Jan 1, 1987

By George S. Rice

In response to numerous requests for information as to the status of internal-combustion mine locomotives of the Diesel type that use heavy or nonvolatile oil for fuel, with special reference to their safe use in coal mines, the United States Bureau of Mines is issuing this t port. Data were obtained on application of such locomotives to coal mining only in Belgium, France, Germany, and Great Britain. The locomotives are used in coal mining in other countries, as well as in potash, iron, and other kinds of mining, but their chief development has been in coal mining in Germany, France, and Belgium. Recently popular interest in the Diesel type of engine for motive purposes was aroused in this country by the successful application of Diesel engines to railroad locomotives hauling fast transcontinental trains, and, according to published statements, at a low cost of fuel per mile of run.

Jan 1, 1936

By Edward L. McHugh, Charles Sabine, David G. Long

While less than 1% of reported mine accidents are associated with slope stability problems, slope failure accidents were responsible for about 15% of U.S. surface mine fatalities between 1995 and 2003. Small rockfalls, which may involve hand-sized rocks weighing only a few pounds, can cause fatal injuries to workers away from the protection of large machinery. Massive highwall failures containing a million cubic yards of material or more can be fatal even for heavy-equipment operators. As part of an ongoing study at the Spokane Research Laboratory, several remote sensing technologies are being evaluated as tools to assess slope stability and monitor slopes for hazards. An interferometric radar device capable of detecting very small displacements on slopes has been assembled and tested. Radar techniques can provide new tools to augment current methods for monitoring ground control hazards in mines.

By William C. McBee

Sulfur concretes have been developed by the Bureau of Mines as construction materials with physical and mechanical properties that suit them for use in acid and salt corrosive environments where conventional concretes fail. Mixture design methods were established for preparing sulfur concretes using different types of aggregates and recently developed mixed-modified sulfur cements Bench-scale testing of the sulfur concretes has shown their potential value. Corrosion resistance, strength, and durability of sulfur concrete are superior to those of conventional materials. Field in situ evaluation tests of the sulfur concretes as replacement for conventional concrete materials are in progress in corrosive areas of 24 commercial chemical, fertilizer, and metallurgical plants.

Jan 1, 1983

Study to develop a new and more cost effective equipment system, incorporating a winch-pulled dozer blade, for leveling spoil and performing reclamation of area strip mines.

Jan 1, 1975

By Henry E. Hilliard

The production, use, and emission of vanadium in the United States has been traced for the year 1991. Consumption was 3,300 tons2, exports 1,285 tons, and imports 2,013 tons. About 98% of production was used in metallurgy; the remainder was consumed in chemicals, including catalysts. Total emissions to the environment in 1991 were estimated at about 3,100 tons, including emissions due to the combustion of coal and petroleum products. Emissions resulting from the production of ferrovanadium were 130 tons, and emissions from the production of steel about 6 tons. Dissipative losses, defined as losses that occurred during use or as a result of wear, were estimated to be no more than 3 tons. Disposal losses were estimated to be about 4,600 tons. Most of these losses were steel products that contained 0.1% or less vanadium and mayor may not have been recycled. When these products are recycled by the steel industry, vanadium ends up in the steelmaking slag and does not return to vanadium use cycle. Worldwide emissions due to anthropogenic and natural sources were briefly reviewed. It was concluded that industrial emissions were about three times greater than emissions from natural sources.

Jan 1, 1994

Coal research and technologic work by the Bureau of Mines covers a broad program of investigation aimed at conservation and utilization of this important natural resource. Conservation is served by a constant search for higher efficiencies in mining, preparation, and use. Increased utilization is sought through various projects that probe new ways to use coal and expand existing coal markets. This report, the twenty-eighth in the series,3 gives the highlights of Bureau of Mines coal research and technologic work in 1963. The scope and complexity of the program makes it virtually impossible to report all progress on every project, even tor a 12-month period. Full insight into each project can be gained only through intensive review of basic objectives, past accomplishments, and current status of the work. Details of the work are given in numerous publications issued by the Bureau and its laboratories and centers located throughout the country.

Jan 1, 1964

Coal research and technologic work by the Bureau of Mines covers a broad program of investigation aimed at conservation and utilization of this important natural resource. Conservation is served by a constant search for higher efficiencies in mining, preparation, and use. Increased utilization is sought through various projects that probe new ways to use coal and expand existing coal markets. This report, the twenty-eighth in the series,3 gives the highlights of Bureau of Mines coal research and technologic work in 1963. The scope and complexity of the program makes it virtually impossible to report all progress on every project, even tor a 12-month period. Full insight into each project can be gained only through intensive review of basic objectives, past accomplishments, and current status of the work. Details of the work are given in numerous publications issued by the Bureau and its laboratories and centers located throughout the country.

Jan 1, 1964

By R. W. Van Dolah

A premature detonation of an explosive charge occurred on January 30, 1961, at a face being prepared for blasting in the underground Jefferson Island Salt Mine, Diamond Crystal Salt Co., Jefferson Island, Iberia Parish, La. The accidental blast injured the powderman fatally; his helper was injured also, but recovered. The accident represents the first fatality reported to the Bureau of Mines in connection with the use of ammonium nitrate-fuel oil (AN-FO) blasting agents in underground mining in the United States. Representatives of the Bureau of Mines Explosives Research Laboratory, Pittsburgh, Pa., and field representatives of the Bureau's Health and Safety Activity conducted the investigation, upon request of the manufacturer of the ammonium nitrate being used and with concurrence by the mine management.

Jan 1, 1962

By Robert C. Bates

Variations in water percolation rates through saturated cohesionless hydraulic backfill (mill tailings) have been studied in relation to the many physical aspects of the system to determine the most important factors in causing these variations. A multivariable least-squares regression analysis of 135 separate tests shows that a reliable estimate of the water percolation rate through typical hydraulic backfill can be made if the bulk density (unit weight), specific gravity, and grain-size distribution are known or can be estimated. Equations for predicting percolation rate, coefficient of permeability, and seepage velocity are developed both for the range of data analyzed and for extrapolation. The prediction equations for use within the range of data studied are quite accurate, while the ones developed for extrapolation are less accurate but still give reasonable approximations of flow rates. The equations given are valid for cohesionless materials that are free of clays and micas, exemplified by classified mill tailings. The equation developed for predicting percolation rates is as follows: 1nP20 = 11.39147 + 2.853422 1n(VR X D10) + 0.1747436 VR X Cu -178.8039 D10 X D50 + 311.7034 (DSO )3, (1) where P20 = percolation rate, inches per hour at 20° C; correction factors for other temperatures are given in the text, VR = void ratio, dimensionless, D10 = effective size (diameter in millimeters of the 10-percent-finer grain size), Cu = coefficient of uniformity (ratio of the diameter of the 60-percent-finer grain size over D10), D50 = average size (diameter in millimeters of the 50-percent-finer grain size), and In = natural logarithm (log to the base e). The prediction equation for percolation rate is rather complicated, so for practical use a nomograph that simplifies the solution of the prediction equation was developed.

Jan 1, 1967

By D. Randolph Berry

The United States Bureau of Mines (USBM) awarded a contract to Foster-Miller, Inc. to develop guidelines for the storage and use of Self-Contained Self-Rescuers (SCSRs) in underground non-coal mines. An SCSR is a device capable of supplying, in an emergency, one hour of self-contained oxygen (no breathing of mine air). The information and recommendations in this report were developed primarily from three sources: discussions with mine representatives (including management, labor, and government), site visits in underground mines I and a detailed analysis of every reported non-coal accident which produced d hazardous atmosphere during the 5-year period 1976-1980 -plus ten other major incidents from prior years. Volume IV has three major sections: Recommendations and Discussion (Section 2), Analysis of Mine Accidents (Appendix A), and a Summary of Discussions with Mine Representatives (Appendix B).

Jan 1, 1983

By Joseph Daniels

[Adequate supplies of suitable coal and coke are prime requisites in many industries, particularly those dealing with the utilization of mineral resources, recently interest has been focused on the possibilities of using electricity produced at Bonneville and Grand Coulee, Wash., in many electrochemical and electrometallurgical processes, in which core or some form of carbon is necessary in addition, discussion has been revived on the possibility of making iron and steel by the conventional methods employed in blast and open-hearth furnaces. The subject also is important at this time because of its relationship to industrial preparedness for national defense. A supply of coke from local sources on the Pacific coast is necessary in any program of production for strategic sufficiency of certain materials. An anal trio involving tae establishment of such industries should include detailed data on available supplies of coal, the quality and properties of the coke produced, and the technologic and economic factors involved in manufacture of echo and disposal of byproducts.]

Jan 1, 1941

By Irving Hartmann

[The explosability of coal dusts has been the subject of many investigations studies have been conducted in laboratories, in galleries and in coal faire; of several countries to obtain information on the causes, development, and prevention of mine explosions. Early laboratory experiments on it American colas dealt with pressures developed in test bomb by explosions of dust clouds and with, the effects of gas in the dust atmosphere.5/ Later, the emphasis shafted to evaluation of the relative fleet flammability and the ignition temperatures of coal dusts.6/ Much worthwhile effort was devoted to the development of Laboratory apparatus and test procedures that gave good correlation with large-scale explosion tests in the Experimental cost mine. In recent years a number of special problems were studied, mostly with bituminous Pittsburgh coal dust]

Jan 1, 1954

By Larman J. Heath

Wellbore enlargement was tested using hydrazine hydrate in a gas-storage well in Ohio to increase the well productivity. The wellbore was to be enlarged by chemical disaggregation of the sandstone adjacent to the wellbore. Productivity immediately declined 49.1 percent and gradually declined to zero in 7 months. A down-hole camera survey showed a white-to-gray precipitate covering the entire wellbore surface. The precipitate was chemically analyzed and identified as mostly carbazic acid, a hydrazine derivative of carbonic acid. Formation of this precipitate was not anticipated; this viscous sub-stance caused the gradual loss in productivity of the well. The wellbore was not enlarged. Laboratory tests were run to determine what clay stabilization measures could be taken in sandstone cores to prevent clay swelling and particle migration caused by hydrazine hydrate. Normal clay stabilization methods did not prevent the virtually complete loss in permeability to hydrazine hydrate. Other laboratory tests using natural gas diluted with small amounts of carbon dioxide confirmed the ease with which carbazic acid could be formed in a hydrazine hydrate-saturated environment within and adjacent to the wellbore.

Jan 1, 1970

By R. R. Falier, W. E. Rice

"PURPOSE OF REPORTThis paper presents the results of a series of tests made by the U. S. Bureau of Mines in cooperation with The Ohio State University Engineering Experiment Station as part of an investigation on the use of fuel in kilns.This report is preliminary and gives only enough of the test data to illustrate results and show the reasons for the successes and failures of the method of firing investigated; fuller details will be included in the final report.PERSONNEL FOR TESTSThe investigation is conducted under supervision of P. Nicholls, supervising fuel engineer, of the United States Bureau of Mines, and G. A. Bole, research professor, of The Ohio State University. These tests were made under direction of W. E. Rice, associate fuel engineer, assisted by R. R. Faller, assistant fuel engineer, of the United States Bureau of Mines; H. C. Harrison, senior research engineer (until October 1, 1930), C. R. Austin, senior research engineer (since October 1, 1930), and H. K. Van Sohoick, junior research engineer, of The Ohio State University. M. J. Rice, field engineer, represented the manufacturer of the stoker.PURPOSE OF INVESTIGATIONThe general aim of the investigation is to develop more economical methods of using fuel in kilns and to improve the over—all efficiency of the process of firing by methods that will produce ware of better quality. One phase of this investigation is the burning of coal on an automatic stoker to gain the advantages of control, constant rate of application of heat, and ability to burn cheaper coal than can be used in the hand—fired furnaces of kilns. It a stoker in to be used it is desirable that the coot of the installation should be low, the control of operation simple, and the distribution of heat in the kiln as good or better than with hand firing. These desiderata were sought in the stoker and furnaces that were used for the tests described herein. The tests were made to determine whether it is feasible to fire a large kiln with a single stoker, whether the use of a single furnace simplifies control, and whether the admission of all the hot gam at the center of the kiln will give symmetrical distribution of heat."

Aug 1, 1931

By John C. MacCartney

In the Pennsylvania anthracite region, the principal source of U.S. anthracite, refuse disposal problems are common since cities and towns are located over the anthracite measures. The Bureau of Mines surveyed refuse banks in the area, determining that 863 banks containing aver 910 million cubic yards of material occupy a total area of about 19 square miles. The vast bulk of the refuse is located within 2 miles of the traffic centers of incorporated c unities which have a total population of 625,000. Twenty-seven banks are burning, causing considerable distress in a number of communities.

Jan 1, 1969

By Lawrence J. Froisland

To aid in minimizing adverse environmental impacts of mining and mineral processing, the Bureau of Mines studied changes in soil characteristics in topsoil stockpiled during mining operations. Topsoil stockpiles in arid areas of New Mexico, Utah, and Wyoming were sampled over a 1- to 8-yr period to determine any changes in physical, chemical, or biological parameters in the top 15 ft of soil. Parameters examined in this study included soil moisture, pH, electrical conductivity, and cation exchange capacity; total nitrogen, organic carbon, carbon to nitrogen ratio, extractable potassium, and soluble phosphorus levels in the soil; general levels of bacteria activity in the soil; and productivity of the soil as measured by shoot yield in growth tests. Data were analyzed by multiple linear regression to determine possible effects of stockpile age and depth. Bacteria population counts, used as an indicator of goner l bacterial activity, was the only parameter found to be significantly correlated with stockpile age and depth at more than one site. Bacterial activity increased with depth at the two sites where it was measured. Activity increased with age at one site and decreased with age at the second. Significant changes in soil pH, electrical conductivity, and moisture were significantly correlated with stockpile age and depth at single sites. This study did not show significant, consistent deterioration in soil characteristics or growth yield of topsoil stored in stockpiles.

Jan 1, 1987

By R. L. Rough

Photoelastic, wire resistance, and borehole-deformation gages were used to measure the in situ strains when an outcropping Black Hand Sandstone Formation in Hocking State Forest, Hocking County, Ohio, was overcored to stress-relieve the surrounding sandstone. Strains transmitted to the photo-elastic gage did not produce isochromatic patterns suitable for quantitative analysis. Strain readings from the wire resistance gage indicated tensile-strain loading during overcoring; readings from the strain-gage bridges in the borehole-deformation gage indicated compressive-strain relaxation during overcoring. The magnitude and orientation of the computed stress fields obtained from both gages were comparable when the corresponding tensile and compressive elastic moduli were applied. Stresses computed from deformation and resistance gages at depths to 5 feet showed the maximum stresses to range from 1.042 to 2.121 times greater than the minimum stresses. The bearings of principal stresses calculated from the deformation gage readings varied between N 61° E and N 83° E; the wire resistance strain gage bearing computations varied between N 68° E and N 82° E. Measurements of in situ strain in sandstone were shown to have promise but to require further development in field technique that could likely be achieved through experience.

Jan 1, 1971