Search Documents

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

The Bureau of Mines is active in programs pertaining to solid waste disposal and land reclamation. Nine reclamation projects of mining companies and six projects of the Commonwealth of Pennsylvania were investigated to provide information on the procedures, costs, and results obtained from reclamation projects of bituminous coal-waste disposal areas. Refuse disposal costs of mining companies ranged from 9 to 28 cents per ton-mile, and quantities disposed of ranged from 600 to 4,500 tons per day. Spreading and compacting the refuse at the dump site ranged from 3 to 20 cents per ton. Cost of covering with soil and planting ranged from $750 to $1,646 per acre. Total costs of reclamation for the Pennsylvania projects ranged from about $1,800 to more than $15,000 per acre. Refuse preparation costs ranged from $772 to $5,550 per acre. Soil covering and planting costs ranged from $1,083 to $5,086 per acre. The best results were obtained by soil preparation and conditioning prior to planting. The type and depth of soil and effect of climate were also factors.

Jan 1, 1973

By R. Blickensderfer

Laboratory wear testing was conducted by the Bureau of Mines on a variety of typical wear-resistant alloys used in mining and mineral-processing equipment to establish their relative spalling and abrasion resistance. Test specimens in the form of 75-mm-diam balls were subjected to repeated impacts until they broke, spalled excessively, or received several hundred thousand impacts. Pin specimens removed from the balls were evaluated for high-load abrasive wear. The alloys in-cluded commercial forged steels, cast steels, manganese steels, and four types of white cast iron, with a range of heat treatments. The effects of hardness and microstructure on impact wear and abrasive wear are discussed. The data should help mine operators select the compositions and heat treatments that best suit service conditions.

Jan 1, 1985

Federal Regulations require MESA to regulate the exposure of workers to inhalation hazards in the surface work areas of coal mining and processing operations. (1) The purposes of this study are listed below: 1. Determination of candidate inhalation contaminants for surface work areas of coal mining and processing operations. 2. Selection of appropriate sampling and analytical methods. 3. Performance of qualitative surveys of 56 representative coal mining and processing facilities. 4. Preparation of handbook to provide guidance for inspectors sampling for these contaminants. This report describes the work which was done to accumulate the information which was used in preparing the inspector's handbook. Specifically, this report contains descriptions of the surveys which were performed, analytical results obtained from these surveys, findings and conclusions, and recommendations for additional research.

Jan 1, 1975

By Hillary W. St. Clair

This is an initial progress report on a theoretical study of the iron blast furnace. The purpose is to develop a thermochemical model that will simulate mathematically a real furnace. An analysis is made of the behavior of a hypothetical furnace, operating adiabatically on pure ferric oxide, graphitic carbon, and dry air. Relationships are derived for carbon consumption, gas composition, and reaction temperature for a furnace operating at steady state, and in which the smelting rate is slow enough for the gas and solids to approach thermal and chemical equilibrium. Analyses are made for two contrasting types of gas flow: (1) Nonturbulent flow, having no vertical mixing; and (2) turbulent flow, having perfect mixing during each step of the process. It is shown that some vertical mixing is essential for complete reduction of ferrous oxide and that the extent of vertical mixing is one of the critical factors in the behavior of the furnace, This analysis indicates that the thermochemical relationships in a blast furnace can probably be best simulated by a finite series of gas-solid reactors through which gas and solids flow countercurrently and in which the temperature and composition of gases and solids are assumed to be uniform. Any degree of vertical mixing can be approximated by the proper choice of the number of reactors.

Jan 1, 1963

By Richard G. Stearns

Extensive thick lignite apparently lies within 250 feet of the land surface in Dyer, Lake, Lauderdale, Obion and Tipton counties. Information on geology, land use, soils, groundwater and instability is compiled, along with a bibliography. A test and monitoring site was investigated at Fort Pillow Prison in Lauderdale County. Analyses were made of lignite, overburden, associated water and leachate. Lignite has high BTU (about 7800) and low sulfur (1.1% avg.). A year or more of data are presented on rainfall, water levels, and chemistry of surface water, groundwater, leachate and water from test pits. Main potential environmental problems are quality of surface water, and possibly shallow groundwater. The main aquifer of the region will likely be un-affected by mining. Low transmissibility of shallow aquifers will minimize lowering water levels of wells. Soil reclamation and conservation should be readily accomplished, Dangerous earthquakes have a low probability and mines are not significantly more hazardous than steep bluffs.

Jan 1, 1981

By Donald O. Capstick

[ ]

Jan 1, 1983

By Eric H. Brown

One of the best methods by which the results of accident-prevention work can be measured for any particular period is to keep an accurate record of the accident experience, which may then also be compared with the experience of others. The purpose of this report is to compare records of the salt-mining companies operating in Louisiana, and their assistance in making available their accident records is gratefully acknowledged. PRODUCTION Four companies produce salt in Louisiana -Avery Salt Co., Avery Island; Jefferson Island Salt Mining Co., Jefferson Island; Myles Salt Co., Weeks; and Carey Salt Co., Winnfield. Three of these companies operate within 30 miles of each other in the southern part of the State, and the other operates in the central part.

Jan 1, 1938

By G. C. Price

This study traces the development of the bucket-wheel excavator, points out the differences in the German- and American-type wheels, and gives the major design criteria and the advantages and disadvantages of bucket-wheel operations. A computer program, written in FORTRAN IV for use with an IBM 360 computer, simulates the operation of the digging components of a bucket-wheel excavator. By supplying certain mining dimensions, soil characteristics, and machine design specifications, this program will print out a time study of the various components of an operation, power calculations for the operation, and production data. This program, when combined with a truck, belt, or rail program, should be helpful in planning a complete mining system In material suitable for a bucket-wheel excavator operation.

Jan 1, 1973

By P. R. Jones

A computer program was written for the design of a shell and tube heat exchanger on a price optimum basis for the following conditions: (1) Triangular pitch; (2) single or multiple pass; (3) heating or cooling; (4) no change in phase; and (5) inside pumping costs immaterial. Price optimum design was obtained for four standard tube sizes and standard pitch. The inside pressure drop was fixed and outside pressure drop was computed for the optimum baffle spacing and when the baffle spacing equaled the shell diameter. Standard shells whose areas equaled or exceeded the required area were also listed. The program was made adaptable to various fluids and to various tube sizes and pitch by reading in many of the required data such as physical properties of the fluids, tube data, and standard shell data in tabular form.

Jan 1, 1968

This briefing was sponsored by the Bureau of Mines to summarize ongoing and recently completed chromium-chromite research and resource assessment activities by the Bureau. Through the series of 18 presentations compiled herein, Bureau personnel covered a wide range of topics including U.S. chromite and chromium trends and usage patterns; foreign and domestic resources; and research activities on mineral characterization and beneficiation, chemical and pryometallurgical processing of chromite and chromium-bearing wastes, new low-chromium alloy and coating substitutes, corrosion- and oxidation-resistant stainless steels, and chromium-containing refractories.

Jan 1, 1986

By Cecil Q. Cupps

Results are presented of a comprehensive study of the characteristics of the original oil in the Weber sandstone reservoir, Rangely oil field, Colorado. Through the medium of subsurface sampling, adequately representative samples of the original reservoir oil were obtained from many parts of the reservoir over a period of 5 years concurrent with active development of the reservoir. Data of differential gas liberation, pressure-viscosity, and. pressure-volume-temperature relationships are shown for 12 subsurface oil samples. Data also are given of reservoir pressure and. temperature, composition of liberated or solution Gas, composition of 22 produced-gas samples, and Hempel analyses of crude-oil samples from 18 wells. The characteristics or physical properties of the 12 subsurface oil samples, as determined by laboratory analyses, were correlated with elevation of the top of the Weber sandstone. These relationships of oil characteristics to elevation in the reservoir show that only the oil in contact with the initial gas cap was gas-saturated at the existing pressure and temperature. The characteristics of the original reservoir oil were marked by an appreciable decrease of saturation pressure and solution gas-oil ratio and increase of viscosity and density with depth below the gas-oil contact. The composition of solution gas and of' produced was also was found to vary with elevation of the oil in the reservoir.

Jan 1, 1951

By D. Harrington

The mining industry of the United States has-long been severely criticized because of its high rate of accident occurrence, net only as compared with other major industries-in the United States but also with the mining industries of other countries particularly Europe. Statistics (often not of strictly comparable nature) indicate that the accident-frequency rate in all mining is currently about three times and the accident-severity rate is about seven times as great as the average for general industrial work in the United States. These figures are by no means comforting to humanitarian mining men, irrespective of their status in. the industry, and they constitute a challenge that certainly cannot continue to be ignored much longer. This picture becomes much darker when the above statistics are augmented with data indicating that. on an exposure basis our mines (more particularly our coal mines) have accident rates two, three, or even more times as great as more or less similar types of mines in Europe, particularly England and Wales, Belgium, France, and Germany. However, these foreign accident statistics should be carefully analyzed before we become very mush concerned about them, because they are clot strictly comparable owing to several considerations, not the least of which is the fact that foreign methods of compiling or recording accident statistics often differ materially from ours. Moreover, foreign mining and other conditions axe definitely dissimilar to ours in many if not most phases, and numerous ether factors affect the comparability of foreign mine-accident statistics with ours. Unquestionably it should also be taken into consideration that the accident rate of the 130,000,000 or more constituting the populace of the United. States as a whole is much higher than that of any other major country in the world and is two, throe, or more times the rate of the European countries that have more favorable mine-accident rates than those of the United States. Moreover, it is significant that the mine-accident-severity- rate of British mines is about six times the average accident-severity rate of the major industries of the British Isles, or but little mere, favorable than the comparable figures in the United States, namely, that mining-has an accident-severity rate about seven times that of the average of about 30 of the major industries of this country.

Jan 1, 1941

By Wilton Johnson

Native asphalt was produced by three companies in two States, Texas and Utah. Bituminous limestone, used primarily as a paving material for street and road repair, was produced by one firm, R. L. White Co., Uvalde County, TX. Gilsonite, a solidified hydrocarbon found only in Colorado and Utah, was mined by two firms, American Gilsonite Co., a division of Chevron Resources Co. (a subsidiary of Standard Oil Co. of California), and Ziegler Chemical and Mineral Corp. Hydrocarbon Mining Co. (a subsidiary of Oberon Oil Inc., a Utah corporation) closed its mining operation during the year.

Jan 1, 1988

By S. Don Brown

Between 1987 and 1988, the Bureau of Mines studied the mineral resources of the White River National Forest and part of the Arapaho National Forest to appraise the resources present and to determine the types of deposits, and their location, that could be mined economically if sufficient demand and metal prices existed. The study included a comprehensive literature search and a limited amount of field investigation of minerals and mining activity in and near the Forest. Mineral resource information indicates that in the Gore Range the area between Tennessee Pass and Gilman may contain large base-and precious-metal deposits, and could be the focus of exploration activity in the near future. The Breckenridge mining district was found to have a moderate to high likelihood for mineral exploration and possible development of gold. Recent exploration and minor development work has occurred in several other areas: Montezuma, Kokomo-Tenmile, and Upper Blue River districts, and portions of the Sawatch Range. Limestone, marble, sand and gravel, rock for crushed aggregate, and other industrial rocks have been recently mined or Quarried in the Forrest, and will likely be mined or quarried in the near future. Currently coal is being produced at one mine in the Forest, and extensive identified coal resources are located in the Forest. Parts of four known gas fields lie within the Forest west of Glenwood Springs; there is current production at one field.

Jan 1, 1990

By Forrest T. Moyer

INJURY experience and employment data are presented in this chapter for metal and nonmetal mines, stone quarries, sand and gravel pits, iron blast-furnace slag plants, and metallurgical plants (including ore-dressing and nonferrous reduction plants and refineries) in the United States. Employment and injury experience data for all mineral industries are given in volume II. The 1962 figures are preliminary summations which are subject to revision. They were compiled from all reports from producers received by the Bureau of Mines through April 15, 1963. The data for metal, nonmetal (except well and brine operations), stone, and sand and gravel operations were collected by a mandatory reporting system under the provisions of the act of September 26, 1961, Public Law 87-300 (75 Stat. 649). The act authorized the Secretary of the Interior to study the various aspects of safety in metal and nonmetal mines (excluding coal mines) and report the findings 2 years sub-sequent to the enactment of the law. Data on nonmetal well and brine plants and nonferrous reduction plants and refineries were reported voluntarily by the operators. METAL MINES Preliminary data for the metal mining industry comprise reports on 1,871 mines and pits. The combined fatal and nonfatal injury-frequency rate was 31.95 per million manhours in 1962, a decrease of 8 percent from the similar rate of 34.54 in 1961. Metal operations reported a total of 61 fatal and 3,201 nonfatal injuries.

Jan 1, 1963

By William Seymour

"INTRODUCTION Byproduct-coke manufacture is one of our country's most essential in¬dustries; its importance was strikingly accentuated by the demands of World War II. This paper reviews recent progress in various phases of byproduct-coke operations for the production of metallurgical coke particularly that used as blast-furnace fuel.In the early days of the by-product-coke industry in the United States high-grade bituminous coking coals, both high-volatile or gas coal and low-volatile Pocahontas coal, were plentiful, and the selection and mixing of coals for coke-oven use were minor problems.The demands of World War I for the production of iron, steel, and coke aroused and stimulated new interest in the investigation of the reserves, characteristics, and properties of our coking coals. During that war the increased demand for coke reached a critical stage, and the shortage of high-grade coking coals necessitated the use of cols of inferior quality and of different coking characteristics than those previously used.The period of prosperity following World War I brought much progress and development in the by-product-coke industry. Methods of testing coal and coke were improved. The search for satisfactory coking coals was continued, and construction and design of byproduct ovens were improved."

Jun 1, 1946

LARGE-SCALE production of zirconium by the Northwest Electrodevelopment Laboratory of the Bureau of Mines at Albany, Oreg., is an anomaly that justifies some explanation. The reduction of titanium tetrachloride with magnesium in an inert atmosphere, as perfected by Dr. W. J. Kroll before 1940, aroused renewed interest in zirconium, and in 1945 development work on this metal was initiated at Albany under Dr. Kroll's technical direction. Preliminary results were promising, and in February 1947 a pilot plant with a weekly capacity of 60 pounds of zirconium-metal sponge was put in operation. Shortly thereafter the Oak Ridge National Laboratory of the Atomic Energy Commission requested production of 1 ton of zirconium-metal sheet, with the provision that it have a low hafnium content. The Bureau of Mines was furnished with a. supply of Brazilian baddeleyite ore, containing less than 1 percent hafnium with respect to zirconium, from which was made about. 2,700 pounds of relatively low hafnium zirconium sheet of 0.080-inch thickness for test purposes. This was accomplished by melting zirconium sponge in a graphite crucible, hot-rolling the ingot in an iron sheath, and finishing by cold rolling. Concomitantly the Oak Ridge Laboratory developed a method for separating hafnium from zirconium; and, in cooperation with the Atomic Energy Commission and the Bureau of Ships of the Department of the Navy, a, larger pilot plant was erected to produce zirconium from very low hafnium zirconium tetrachloride furnished by the Commission. Pilot-plant work on producing zirconium tetrachloride from zircon sand and baddeleyite was discontinued. Production of zirconium sponge in the larger pilot plant of 500 pounds per week capacity was begun in June 1949.

Jan 1, 1956

By Parry. V. F.

"SUMMARY This report reviews the status of the packaged-for industry as of 1941. A field study was made of 35 representative plants to obtain technics and economic data on different types of processes used to make packaged fuel in the Central States. The report includes a classification of processes, photographs of typical operations, designs of different plants, an analysis of costs of manufacture, and a study of the physical and chemical properties of fuel cubes.It was observed that many of the smaller plants were having troubles in the manufacture of packaged fuel as the price of materials and costs of labor advanced toward the higher levels of 1942. In some instances, the total cost of manufacture was as high as $5.00 per ton, while in the better, medium-sized plants it was approximately $3.25 per ton. The direct manufacturing costs, excluding investment and depreciation, ranged from $3.17 to $2.37. These costs permit almost no profit at small plants when packaged fuel sells for the same price as competing lump coal under conditions existing in 1941-42.It was found that the predominant troubles in plants were due to inadequate drying and insufficient mixing of the starch binder. It was ob¬served that in the better plants, where proper mixing of binder was attained high-quality packages were made if 50 to 70 percent of the moisture was removed in the drying ovens. Experimental data obtained in the laboratory show the relationship between the temperature of dry air and the time required to remove different percentages of moisture in wrapped orunwrapped coal cubes.The average physical and chemical properties of fuel cubes made by five processes are listed, and tentative standards for minimum physical qualities and methods for measuring quantity are giver."

Jun 1, 1944

By Stephenson. E. L.

"INTRODUCTION In the spring of 1942 a series of magnetometer surveys on deposits of black sand underlying Pleistocene raised marine terraces along the coast of southwestern Oregon was nada by the Division of Geophysical Exploration of the Federal Bureau of Mines in cooperation with the Oregon Department of Geology and Mineral Industries. A few preliminary tests had been made in the same area in May 1940 and December 1941.The sands contain fine gold and metals of the platinum group, and, beginning in 1852, extensive, but spasmodic mining and exploration have been done for these precious metals. There are many old placer, mines and prospects, although for the most part the yield of the metals has been small. The sands also contain other minerals of potential value, including ilmenite, magnetite, garnet, zircon, and particularly chromite, and the wartime demand for domestic chromite resulted in extensive testing and development of the known deposits. The purpose of the magnetometer surveys was to determine the efficacy of, magnetic methods in tracing and outlining these known deposits and in prospecting for new ones. The field work was done between March 17 and May 29, 1942, by the author assisted by W.W. Paulsen of the Oregon Department of Geology and Mineral Industries."

Jun 1, 1945