Search Documents

By Kenneth G. Skinner, Hewitt Wilson, Thomas L. Hurst

Although chromite deposits occur in California , Oregon, Washington, Montana, Wyoming , Pennsylvania, Maryland , New Mexico , North Carolina, Alaska, and the Phillippine Islands , less than 1 percent of the ore used in the United States is obtained from these deposits . Most of the ore in peacetime has been supplied by imports from South Africa, New Caledonia, Turkey, and Cuba . The mineral chromite , the most important chromium ore , is an isometric spinel with an ideal composition of FeO Cr2O3 , but commercial chromite has the variable composition (Fe , Mg) Oʻ (Cr , Al , Fe) 203. Chromite has a black color , a specific gravity of 4.4 , and a hardness of 5.5 . In thin section the color is reddish -brown to black . Chromite occurs in dunite and pyroxenitic ultrabasic rocks , which are composed of iron- magnesium silicate minerals such as olivine , saxonite , serpentine , and enstatite . These are also the gangue minerals . Com mercial ore occurs at random in the country rock in kidney- or lens - shaped deposits , which have no apparent relationship to each other . Stringers , veins , and bands often cut the country rock without regard either to fracture or to other deposits . Some beach sands , such as those in southern Oregon, contain chromite .

Mar 1, 1943

Research personnel from the Bureau of Mines, representatives of the Mining Enforcement and Safety Administration (MESA), and members of the mining industry met with other Government and Industry representatives at three seminars held in Pittsburgh, Pa., November 4, 1975; St. Louis, Mo., November 6, 1975; and Denver, Colo., November L1, 1975, to discuss the results of Bureau-sponsored research on coal mine illumination. The program, aimed at developing suitable illumination systems fur the working; places of underground coal mines, covered hardware development and field evaluation and the status of proposed MESA standards and proposed MESA enforcement procedures. These proceedings contain the opening remarks to the seminars and eight technical presentations an various aspects of coal mine illumination.

Jan 1, 1976

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

By R. S. Dean

This report, the third of a series of annual reports of the Metallurgical Division to be released in this form, covers the fiscal year July 1, 1936, to June 30, 1937. The technological work of the division is performed by sections. Thus, an efficient organization is provided to prosecute the various problems under investigation, and a logical system is set up for presenting the material contained in this report.

Jan 1, 1937

By William O. Vanderburg

Tis paper describing the mining practices at the Cold Springs mine of the Wolf Tongue Lining Co. at Nederland, Colo., is one of a series of similar papers prepared by the Fureau of kines on mining practices, methods, and costs at various mines in the United States. The writer acknowledges the assistance of William Leach and William T. Todd, manager and mine superintendent of the Wolf Tongue Mining Co., respectively, in the preparation of this paper.

Dec 1, 1932

By Charles L. Kusik

A study was conducted for the Bureau of Mines, U.S. Department of the Interior, to provide information which will lead to an increase in the recycling of mineral materials, in order to help conserve the Nation's mineral resources. Data were collected on energy requirements to recycle prompt industrial and obsolete scrap for nine metal commodities: Iron and steel, aluminum, copper, zinc, lead, stainless steel, titanium, tin, and nickel and nickel alloys. Major process routes for recycling were considered, starting from the first collection point through scrap preparation, transportation, smelting and/or refining to the molten metal, ingot, or other semi- finished form approximately equivalent to a primary metal of a similar composition. Available data for 1976 were collected on the amounts of each metal commodity recycled by major scrap categories. In addition, energy requirements were estimated for separating municipal solid wastes into four major categories: Refuse-derived fuel, and magnetic, aluminum, and glass cullet fractions. Finally, areas of research were identified to enhance recycling and/or increase the efficiency of energy use.

Jan 1, 1978

By Bruce F. Grant

"INTRODUCTION The future of oil production in the part of the Appalachian region included in southwestern Pennsylvania; West Virginia, and southeastern Ohio is directly dependent on the maintenance of existing wells. This report presents an analytical study of the methods used in oil-well reconditioning in this area. The study is part of a research program designed to evaluate those means of stimulating oil production that can effectively and economically maintain present oil-production rates and make it possible to keep existing wells in operation. Well-reconditioning work was curtailed during the war; therefore, an abnormally large number of wells in the Appalachian Region is now in need of repair. Because the lubricant content of Appalachian crude: oils is high and the refined lubricating oils an; particularly suited to use in high speed, high-temperature engines, the demand for these crude oils during the war exceeds, the maximum rate of production obtainable under wartime operating conditions. Increases in operating, expenses, inability to meet war-time reconditioning costs, and inflexible price structures caused the abandonment of an alarming number of wells during the past 4 or 5 years.As a means of increasing regional oil-production rates, new drilling in the older fields for primary production generally is uneconomical because reservoir pressures in most of the fields have virtually been depleted and the production rates of newly drilled wells are small."

Feb 1, 1948

A symposium on pneumatic transportation of solids was held at Morgantown, W. Va., October 19-20, 196'), under the cosponsorship of the Institute ref Gas Technology. Chicago, Ill., and the Bureau of Mines. Objective of the symposium was to present information on developments and projected programs in the technology of feeding, transporting, recompressing, and utilizing gas-solids mixtures Dr. Henry R. Linden, Director, Institute of Gas Technology and Harry Perry, Director of Coal Research, Bureau of Mines, in the initial addresses at the symposium welcomed more than 140 representatives of industry, educational institutions, and government from 16 states, Canada, Great Britain, etc.

Jan 1, 1966

A symposium on pneumatic transportation of solids was held at Morgantown, W. Va., October 19-20, 1965, under the cosponsorship of the Institute ref Gas Technology. Chicago, Ill., and the Bureau of Mines. Objective of the symposium was to present information on developments and projected programs in the technology of feeding, transporting, recompressing, and utilizing gas-solids mixtures. Dr. Henry R. Linden, Director, Institute of Gas Technology, and Harry Perry, Director of Coal Research, Bureau of Mines, in the initial addresses at the symposium welcomed more than 140 representatives of industry, educational institutions, and government from 16 states, Canada, Great Britain, etc.

Jan 1, 1966

By J. A. Kost

A dust-control manual was prepared for use by mine operations personnel. The manual documents state-of-the-art control techniques, dust sampling, and use of personal protective devices. Content addresses advantages/disadvantages of control techniques, design and operating specifications, and implementation and maintenance guidelines. An indexed list of selected references is also included. In addition to the completed manual, this report documents work performed in the course of its preparation.

Jan 1, 1981

By L. J. Kane

Applications are described of various methods for determining the weight concentration and physical properties of solid and liquid impurities of gases in connection with problems encountered in synthesis-gas production. Of special interest among these methods may be listed: 1. A method developed for determining, the weight concentration of solid and liquid impurities in. hot, crude synthesis gas containing a high concentration of moisture. 2. A method developed for the same purpose but for highly purified synthesis gas or atmospheric air. 3. A method for obtaining a uniform dispersion of dry duet or, a microscope slide for particle-size determination or other purposes.

Jan 1, 1954

By Richard S. Fowkes

This Bureau of Mines report describes the Human Factors in Mining Search System (HFMSS), a computerized information retrieval system that provides relevant human factors information from journal articles, research reports, seminars, conferences, etc. in terms of 19 mining-related categories. It is the only existing data base that stresses all of the areas of human factors as applied to mining. Examples of these categories are biomechanics and work physiology, human error and human reliability, work design and task analysis, manual materials handling and back injuries, hand tools, organizational and management practices, psychological factors, and training. Although the emphasis is on literature dealing directly with mining, applicable material from other areas of research is included for those categories in which little research has been done in mining. Each record in HFMSS can be recalled by any field such as title, author, date, source, descriptive terms or key words, as well as by any words found in an abstract that describes the purpose, procedure, and results of the research. This report describes HFMSS fields and subject categories, the annotated bibliography, user's manual, and thesaurus of key words. Example printouts in both brief and full formats are included as an appendix.

Jan 1, 1990

By A. Stawsky

Effective use of diesel vehicles in underground mining requires attention to improved control of diesel exhaust pollutants such as particulate (soot), oxides of nitrogen and sulfur and carbon monoxide. An experimental survey Is made of diesel emission aftertreatment control techniques including water scrubbers, catalytic converters, exhaust gas recirculation (EGR) and soot filters. Use of two or more techniques in combinations are tested for optimum control of all exhaust pollutants. Dynamometer data is developed for steady state and computer controlled simulated mines duty cycles operation of Deutz F6L-714 and F8L-413 engines. Exhaust Quality indices (EQIs) are calculated from dynamometer data for comparisons among the control combinations examined. The Corning diesel particulate filter (DPF) is shown to be the most promising and practical device. The Corning DPF in combination with EGR provided the best (lowest) EQI from the test data. Use of the DPF requires additional regeneration mechanisms such as a catalytic filter coating or fuel additives. A metal mine field test is made of DPFs on an operational scoop tram to test practical applicability. Further development is proposed for application to various mine conditions and for improvement of DPF regeneration techniques including coating with newly available catalysts.

Jan 1, 1987

By Andrew B. Cecala

The U.S. Bureau of Mines has designed and evaluated total mill ventilation systems at two different mineral processing operations. Both systems have proven very effective at reducing respirable dust levels throughout the mill in a cost-effective manner. A 25,500-cfm system installed at a clay processing mill provided approximately 10 air changes per hour. This system reduced respirable dust concentrations by approximately 40 pct throughout the mill building. The second evaluation was performed at a silica sand operation. Tests were performed with 50,000 and 100,000 cfm of ventilation to the mill building, corresponding to 17 and 34 air changes per hour. Average mill-wide respirable dust reductions were 36 and 64 pct, respectively. Not only did these systems reduce respirable dust concentrations and increase visibility throughout the mills, they were also easy to install and required minimal maintenance. A total mill ventilation system provides a general purging of the mill air; the system should be viewed as a supplemental technique to assist other dust control systems in operation.

Jan 1, 2010

By Arno C. Fieldner, Howard I. Smith, J. W. Paul, SAMUEL SANFORD.

Many mine samples of coal are analyzed each year in the laboratories of the Bureau of Mines. The analyses are made in connection with investigations relating to fuels belonging to or for the use of the United States Government, the causes of accidents in coal mines, the geologic relations of coal beds, and the character and the value of the coal and lignite in the public lands. The systematic collection and analysis of such samples in connection with fuel investigations was begun in 1904 at the Government fuel-testing plant at the Louisiana Purchase Exposition, and was under the direction of the United States Geological Survey for six years. Descriptions of the coal samples collected between the beginning of this work, July 1,1904, and the transfer of the fuel-testing and mine-accident investigations to the Bureau of Mines, July 1, 1910, were compiled and published in Bureau of Mines Bulletin 22.a Descriptions and analyses of samples collected during the fiscal years 1911 to 1913 were published in Bureau of Mines Bulletin 85.b The present bulletin presents analyses and descriptions of samples collected during the fiscal years 1913 to 1916. In order that the material in this bulletin may be used to supplement that presented in Bulletins 22 and 85, the same plan of geographical classification has been followed, the analyses and descriptions of the samples being grouped in alphabetical order according to the State, county, and town near which the mines or prospects sampled are situated.

Jan 1, 1918

The Leuna Factory of the I. G. Farbenindustrie A. G., situated near Merseburg, is the biggest heavy-chemical plant in Germany and produces a very wide range of products, mainly based on hydrogen or hydrogen and carbon monoxide. Its principal products are ammonia, synthetic petrol derived from the hydrogenation of brown coal, and synthetic alcohols made from hydrogen and carbon monoxide. The plant was first, visited on April 21, 1945, by a team including E. Cotton, V. Haensel, E. B. Peck, P. K. Kuhne, H. M. Weir, L. L. Hirst, W. W. Odell, G. U. Hopton, H. Hollings, J. F. Ellis, and H. G. Simpson. It was again visited on May 8-24, 1945, by a combined British and American team consisting of R, Holroyd, M. A. G, Banks, D. A. Howes, A. J. V. Underwood, R. A. Taylor, W. F. Faragher, H. Schindler, and J. G. Allen. This team was later joined by J. F. Ellis and R. J. Morley. A third visit with particular reference to catalyst manufacture was made by W. F. Faragher and W. A. Horne, and the notes of these latest investigators have been taken into account in preparing the report. This report was edited by Dr. R. Holroyd.

Jan 1, 1946

By G. H. Gronhovd

This report describes the design and initial operation of a slagging gasification pilot plant installed by the Bureau of Mines at the Lignite Research Laboratory, Grand Forks, N. Dak., in 1958-59. The tests covered in this report were conducted over a period of about 2 years, beginning in April 1959. The pilot plant was designed for eventual operation at pressures ranging from 400 to 600 p.s.i.g. (pounds per square inch gage); however, for the preliminary test reported here, the gasifier was fitted with a low-pressure slagging section and operated at atmospheric pressure and at 80 p.s.i.g. The reason for using a low-pressure slagging section for initial operation was to facilitate modifications in design during the development of a reliable slagging procedure.

Jan 1, 1962

By L. J. E. Hofer

THIS BULLETIN analyzes and summarizes research at the Bureau of Mines dealing with the preparation, properties, and reactions of iron carbides in the period 1948-60, part of which was sponsored by Wright Air Development Laboratories. The objective was to develop better catalysts for the synthesis of methane and higher hydrocarbons from hydrogen and carbon monoxide. The investigations resulted in the first adequate characterization of epsilon iron carbide, which later proved to be an important intermediate in the tempering of martensite in steel. At temperatures near 170° C, the carbon in carbon monoxide reacts nearly quantitatively with finely divided alpha iron to form an iron carbide in which the metal atoms occupy the positions of the close packed hexagonal arrangement with lattice parameters of ao=2.754 A and co=4.349 A. The carbide has a composition within 2 atomic percent of that required for the formula Fe2C, a Curie point of about 370° C, a specific magnetization of 160.4 ergs per gauss-gram Fe at 50° C, and a ferromagnetic moment of 1.70 Bohr magnetons. Epsilon iron carbide can be converted to chi iron carbide by thermal treatment at 343° C for about 70 hours. The chi iron carbide so formed has a Curie point of 247° C, a specific magnetization of 142.5 ergs per gauss-gram Fe at 50° C, a ferromagnetic moment of 1.72 Bohr magnetons per iron atom, and a paramagnetic moment of 5.5 Bohr rnagnetons per iron atom. Direct synthesis of this carbide from carbon monoxide at 240° C indicates a composition within 7 atomic percent of that required for Fe2C. Chi iron carbide can be converted to cementite at 550° C in about 315 minutes. The theta iron carbide so prepared has a Curie point of 210° C, a specific magnetization of 147.3 ergs per gauss gram Fe at 50° C, a ferromagnetic moment of 1.72 Bohr magnetons per iron atom, and a paramagnetic moment of 3.9 Bohr magnetons per iron atom. Pure chi iron carbide reacts to form theta iron carbide by the elimination of free carbon. In the presence of an excess of free iron in intimate contact with the carbide, chi iron carbide reacts with the free iron to form theta iron carbide. The second reaction proceeds at an appreciable rate at 320° C and can be used to snythesize finely divided theta iron carbide with no free-carbon impurity at low temperatures. The ease of the reaction in the presence of free iron suggests that chi iron carbide is an intermediate in the tempering of epsilon iron carbide to theta iron carbide as it proceeds in steels. Experiments on carbon steel show that the magnetic moment of the iron atoms in martensite is about 2.2 Bohr magnetons per atom, a value approximately the same as that of the iron atoms in alpha iron. The Curie points of epsilon iron carbide, chi iron carbide, and theta iron carbide were found -in various specimens of tempered steel to be 10° to 20° C lower than normal values. This shift is probably the result of manganese in solid solution. Preparations of various compositions of epsilon iron carbonitrides show many effects of extensive isomorphism between epsilon iron carbide and epsilon iron nitride. The action of carbon monoxide on finely divided alpha iron at 400° C results in free carbon deposits containing filaments about 0.1 micron in diameter and several times as long. The filaments are characterized by nuclei of dense material located midway from each end of the filament. Although carbiding to near completion at 240° C over periods of about 300 hours produces a preparation containing no appreciable percentage of epsilon iron carbide, very brief periods of carbiding of the order of a minute result in the formation of detectable epsilon iron carbide even at temperatures as high as 325° C. The data indicate that epsilon iron carbide is an intermediate in the formation of chi iron carbide during its formation from carbon monoxide in the gas phase. Attempts to convert cementite to chi iron carbide by cold work increased the Curie point but did not change the X-ray powder diffraction pattern.

Jan 1, 1966

By R. S. Dean

"Applied Mineral Physics, by R. S. Dean.- This is an introduction to the seven papers that follow. It discusses the practical aspects of mineral physics and outlines the theo¬retical viewpoint underlying the investigations reported herein.Explosive Shattering as a Possible Economical Method of Ore Presentation By John Gross and C. E. Wood. - It is shown that explosion shattering by impact is favored by large charges and by low ratio of water to charge. For 400-gram charges of dolomite crushed through 48 mesh the steam costs are less than 5 cents per ton of dolomite obtained. This is within the range of present steam costs for ball-milling dolomite.Electrical Properties of Minersl Aggergates I. Natural and Artificial Aggregates Crystallized Lead Sulphide By R.S. Dean and John Koster - This paper deals with the electrical properties of natural and synthetic galena. It is shown that massive crystalline galena has a normal positive temperature coefficient of resistance, whereas fine-grained steel galena has a negative temperature coefficient, the curve R v. T being exponential in form. That steel galena behaves somewhat like a leaky condenser is indicated by ballistic and alternating-current bridge measurements. In determining the cause of the erratic results of alternating-current resistance measurements it was observed that the measured re¬sistance was a function of the current through the specimen. The direct-current resistance was found to be proportional to the square of a superimposed radio-frequency current and independent of the frequency.The influence of grain size or the amount of metallic interface on the voltage-current characteristics at various temperatures on synthetic galena pastilles was studied. It is proved that the volts v. amperes curves are linear for all sizes and temperatures, that they have an intercept which is apparently a linear function of the temperature, and that their slopes are exponential functions of the temperature and give rise to a negative temperature coefficient of resistance.Apparatus for determing the Magnetic Constants of Mineral Powders by V,H, Gottschalk,and C. W. Davis.- A modified isthmus permeameter having a spark-suppressed primary and a multiplier in the secondary circuit to regulate the effect of capsules functioning as a twin isthmus is used to obtain quantitative data and normal induction and hystersis curves from small amounts of powdered material at fields surpassing 3.000 oersteds. Data and curves are given to demonstrate the calibration of the apparatus and the reproducibility of its results. Applications and limitations of the apparatus are noted.Magnetization Curves for Magnetite Poeders by V. H. Gottschalk and F. S. Wartman.- This paper gives measurements on four lots of purified and analyzed magnetites in mixed fractions with especial reference to the variation of permeability with grain size and with dilution by an inert material."

Feb 1, 1935

The revised estimate of coal production in January 1977, is 39 million tons -- down 12 mi 11 ion tons compared with production in January of last year, largely as a consequence of the snow storms and cold. The major coal-hauling railroads operating in Eastern and Midwestern States reported to the Bureau of Mines that they loaded approximately the same number of cars for the week ended February 5, as in the preceding week. The Bureau of Mines estimates that U.S. coal production for the week ending February 5, 1977, was approximately 8.5 million tons, or nearly 3.5 million tons less than production for the corresponding week in 1976. Coal production from January 1 - February 5, 1977, was approximately 47.8 mi 11 ion tons compared with production of 63.5 million tons for the corresponding period in 1976. As of the first week in February, river and truck shipments of coal in the Eastern U.S. were about one-half of the normal traffic. Despite the freezing weather and ice and snow conditions of rivers and highways and reduced rail shipments, there was reportedly little or no shortage in coal supply to consumers. Inventories at electric utility plants and steel company coke plants at the beginning of the severe weather were sufficient in most cases for at least 30 days" operations. There have been no reports of coal shortages at other industrial plants.

Jan 1, 1977