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By David J. Kusler

The Bureau of Mines reviewed current technology in the refractories consuming industries and evaluated the impact of changes in technology on the supply and demand of refractories. Literature was searched and contacts were made with leading consumers and producers of refractories. The distribution of refractories by value of shipments to users was surveyed. The report shows that the percentage distribution of refractories sales to the consuming industries has remained essentially constant during the last decade but that substantial changes have occurred in the relative distribution of types of refractories. The trend in pyroprocessing technology in recent years has been toward higher temperatures, which require more costly refractories. This fact is reflected in the impressive gain in the dollar value of refractories sales, which in 1968 was about one-third greater than in 1960, and the rapid growth of refractories based on high-alumina, magnesia, zirconia, carbon, and other materials, at the expense of fire clay, silica, and chrome- based refractories. An appendix to the report contains refractories value and shipment data tabulated in a manner by which trends in the distribution of refractory types can be observed from 1955 to 1968. In addition, unit values are presented on a per-ton basis for comparison.

Jan 1, 1970

At the end of August, U.S. producer posting of 99.5 percent unalloyed aluminum had been established at 48¢ per pound. At that time, dealer-quoted unalloyed ingot was reportedly at 44¢-47¢. CADMIUM: By late August, most U.S. producers had raised cadmium selling prices by 25¢ to $3 per pound. As a consequence, dealer quoting of cadmium ranged from $2.95 to $3.05 per pound. COAL: The wildcat strike, which began in southern West Virginia on July 19 and eventually spread to nine other States before ending on August 13, at its peak, idled approximately 115,000 miners and accounted for daily coal losses of an estimated 1.5 million tons at the height of the work stoppage. Concerned about the effects of the production cutbacks, the Bureau of Mines, early in the strike period, initiated its coal strike monitoring system which it had developed during the prolonged coal strike in the fall of 1974.

Jan 1, 1976

By Nathan T. Lowe

This report updates an accounting of mines and prospects in the Seafoam mining district, Custer County, Idaho, begun during mineral appraisal of the Idaho Primitive Area. Thirty-two mine and prospect locations have been added to the Bureau's Mineral Industry Location Subsystem (MILS) data base as a result of initial phases of mineral appraisal of the River of No Return Wilderness; most previously known locations were field checked and the updated information added to the data base. The district's major deposits include polymetallic fissure veins of gold-silver-lead-zinc-copper hosted by granodiorite and quartz monzonite which have been intruded by dikes ranging in composition from rhyolite to dacite, and vein type replacements of silver-lead-zinc-copper hosted by calcareous xenoliths imbedded in major intrusives. These deposits may be related to the intrusion of the Rapid River pluton or the Casto pluton. The dominant northwest structural trend is parallel to an aeromagnetic high, a weak gravity salient, and the Blue Bunch Mountain dike swarm.

Jan 1, 1983

By Charles Vaught, Richard S. Fowkes, Ronald S. Conti, Barbara Fotta, William J. Wiehagen

The purpose of this study was to determine mine workers' state of fire-fighting preparedness and the technology being used to detect and respond to underground coal mine fires. To investigate this problem, 214 underground coal miners were interviewed by U.S. Bureau of Mines researchers. Frequency distributions of workers ' responses are presented in this report, along with segments of narrative accounts, to profile miners' fire-fighting capabilities. The data indicated that much variability exists from mine to mine and that there are several important changes operators may undertake in order to make miners better prepared to deal with fire underground: select appropriate sensors, establish and test a warning and communication protocol, construct a system capable of delivering hundreds of gallons of water per minute for sustained periods, institute formal fire preparedness audits, develop case studies of events that occur at an operation to use as teaching and assessment tools, and provide structured practice that can be incorporated into fire drills.

Jan 1, 1995

By Charles Vaught

The purpose of this study was to determine mine workers' state of fie-fighting preparedness and the technology being used to detect and respond to underground coal mine fires. To investigate this problem, 214 underground coal miners were interviewed by U.S. Bureau of Mines researchers. Frequency distributions of workers' responses are presented in this report, along with segments of narrative accounts, to profile miners' fire-fighting capabilities. The data indicated that much variability exists from mine to mine and that there are several important changes operators may undertake in order to make miners better prepared to deal with fire underground: select appropriate sensors, establish and test a warning and communication protocol, construct a system capable of delivering hundreds of gallons of water per minute for sustained periods, institute formal fire preparedness audits, develop case studies of events that occur at an operation to use as teaching and assessment tools, and provide structured practice that can be incorporated into fire drills.

Jan 1, 2010

By J. J. Drost

The feasibility of basic oxygen furnace (BOF) offgas heat recuperation by preheating scrap was investigated on a pilot plant scale by the Bureau of Mines. In this study, offgases generated during the oxygen blowing of a molten pig iron and scrap charge were passed through a static bed of shredded auto scrap. Scrap quantities varying from 100 to 180 pounds and representing from 22 to 40 percent of the 450-pound BOF metallic charge were preheated in this manner. Average scrap bed temperatures of 1,650° F for 100 pounds of scrap and 1,150° F for 180 pounds of scrap have been achieved during the blows. As compared to cold scrap used in the normal BOF practice, it was found that by preheating scrap, usage could be increased by 43 percent. The thermal energy recovered by this preheating method can account for up to 44 percent of the energy necessary to melt the scrap.

Jan 1, 1974

By Sandip K. Mukherjee

This report presents the results of the economic analysis of several applicable alternatives to increase airflow in four underground coal mines. Pressure-quantity surveys were conducted underground and measurements were also made at the main mine fan(s). The existing ventilation networks were modeled using the modified Penn State ventilation simulator. The applicable alternatives were simulated. Performance data obtained from these simulation runs were utilized to conduct the cost-effectiveness analysis. The costs for each of the alternatives included capital, operating and operating costs. These costs were expressed as annual ventilation costs per active section in terms of dollars per cfm taking into account the economic life associated with each of the alternatives. The benefits were expressed as increased airflow quantity in the critical sections. A section of this report also deals with comparison of simulator predicted air quantity values against air quantity values measured under-ground. This volume constitutes Volume II of the report and contains the outputs of the computer simulation runs.

Jan 1, 1983

By L. N. Plein, J. W. Paul

"The United States Bureau of Mines, in the interest of the prevention of injuries and fatalities in coal mines, has engaged in a study of the circumstances and conditions under which falls of roof and coal contribute to coal-mine accidents, and this publication is devoted to the result of a study conducted in mince developed in the Pittsburgh or No. 8 coal in eastern Ohio.To emphasize the need of this study a statement of the fatalities which have resulted from falls of roof is presented, followed by a brief description of the field and its geology. The mining methods, regulations, and timbering practices are presented and discuss, as well as supervision and discipline, all of which are important factors in the control of the roof and the prevention of falls of roof material that are liable to result in injury to the underground workmen.During the five-year period, 1924 to 1928, there were 10,820 fatalities in the cool mines of the United States, of which number 5,573 or 51.5 per cent resulted from fells of roof material, such as draw slate or roof coal, and of coal from the fact or sides. These fatalities generally occur singly, consequently they are given little publicity compared with major disasters consulting from explosions which, during the same five-year period, amounted to only 17.8 per cent of the total fatalities.Seven,mines in eastern Ohio, each typical, of mines in its locality, have been carefully studied, and the result of this study is herein presented so the information may be and beneficial to all who may be operating mines having,similar natural or physical conditions.In general, it will be found that measures taken to prevent injuries or fatalities from falls of roof as well as other safety measures, will have the effect of increasing the efficiency and economy in mining operation. The result of the study so far made on the falls of roof problem indicates that such features as mine management, supervision, inspection, discipline, character of roof, timbering methods, and blasting have a direct bearing on any scheme that may be evolved to prevent injury or loss of life by falls of roof."

Mar 1, 1931

By Robert L. Montgomery

Heats of solution of samarium (III) oxide and chloride in hydrochloric acid and of samarium (III) oxide, sulfate, and hydrated sulfate in sulfuric acid were measured. The heats of solution of this hygroscopic oxide are larger than those from the literature, probably because of more complete removal of water in the present study. From the literature value for the heat of combustion of samarium, the heats of formation of samarium (III) chloride and sulfate are -244.18 ± 0.41 and -928.5 ± 1.6 kcal./mole, respectively. The heat of hydration of the sulfate is -34.7 ± 1.0 kcal./mole. The heats of formation of other samarium com-pounds have been recalculated, using the new data.

Jan 1, 1959

By W. L. Falke

Research was conducted to develop methods on a laboratory scale for recovering manganese from manganiferous slimes and limestones . The procedure is a low- temperature modification of the carbamate process , in which manganese is dissolved and the valence reduced by treating slimes and limestones with controlled amounts of sulfurous acid . Manganese ( II) hydroxide is precipitated and leached with ammonium carbamate solution , and manganese carbonate is separated by warming the leach solution . A major portion of the reagents is regenerated and recirculated . About 75 percent of the total manganese in manganiferous slimes , and from 50 to 75 percent of the total manganese in manganiferous limestones , are recovered as manganese carbonate containing 45 percent manganese .

Jan 1, 1964

By Gary A. Kingston

This examination of Pacific Northwest (Idaho, Montana, Ore on, and Washington) ferrous scrap-industry opera ions, principally those in Oregon and Washington, points out factors influencing the supply and consumption of scrap materials, such as the complete dependence of steel ingot producers in these States on scrap as a metal raw material and the sizable quantity of scrap exported from Seattle and Portland to Japan. The pattern of the industry is presented as a movement of materials from their diverse sources to the consuming market. The geographic locations of the consuming industries in relation to the area generating scrap materials and the movement pattern of the supply from source to destination strongly influences the cost of the commodity. The best measure of the scrap supply available in an area is experience in terms of how much scrap was withdrawn at a given price. Scrap availability is not finite, because the return of materials as scrap is secular and influenced by constantly varying market conditions. Steel ingot producers use 75 percent of the approximate 500,000 tons of scrap consumed in Oregon and Washington; steel foundries take 15 percent of the total; and iron foundries, ferroalloy plants, and other miscellaneous consumers utilize the remainder. Also, from 1955 to 1960 an average of about 200,000 tons has been exported annually from Oregon and Washington. The foreign exports are supplemented by lesser .shipments to other steel producing States, principally in the western United States. From 1955 to 1960 the preferred and higher value heavy melting scrap grades accounted for about 60 percent of total withdrawals which varied between 600,000 and 950,000 tons annually. Total scrap withdrawals from Oregon and Washington are projected to 1.8 million tons by 1985, 60 percent (1.1 million tons) of which will be heavy melting grades. No. 1 heavy melting scrap is most attractive to scrap consumers at $35 per ton or less. Price-supply relationships compared with projected scrap requirements indicate future prices possibly over $35 per ton. High prices over a long period could motivate the Pacific Northwest scrap consumers to produce steel from iron ore. However, technologic changes taking place at integrated steel plants could reduce scrap withdrawals from the Pacific Northwest, which might keep the scrap price sufficiently attractive to obviate production of competitive iron products by the Pacific Northwest scrap consumers.

Jan 1, 1964

By Harold R. Newman

The performance of Ecuador's mineral industry continued to be affected not only by depressed oil prices in recent years but also by natural disasters. In March 1987, Ecuador canceled foreign debt payments for the rest of the year and appealed for international aid because of a series of earth-quakes that destroyed villages and crippled the nation's oil industry. The earthquake destroyed a key section of the country's main oil pipeline and forced a halt to production and shipment of Ecuador's most important export product. Ecuador produces 240,000 barrels of oil per day and exports 144,000 barrels daily. Oil accounts for 60% of the nation's hard currency earnings. The Government of Ecuador asked the Organization of Petroleum Exporting Countries and other oil-producing countries to assume Ecuador's oil sales commitments. Ecuador agreed to pay the countries back in an equivalent amount of oil when it was able to resume exports.

Jan 1, 1989

By D. B. Dow

The appearance of water in an oil field is the forerunner of various difficulties, and probably represents the greatest technical problem that the producer must face. Water conditions bear-directly on the quantity of oil recovered, and the length of the life of a field. Presence of mater increases the cost of operation, for example, gifting costs. On account of the corrosive action of oil-field waters on pumps and other equipment, frequent replacement of equipment is necessary. Furthermore, water may affect the marketability of the oil produced, as detrimental emulsions of water in oil (?B.S.?, "cut oil", etc.) are often formed. The writer has recently completed a study of oil-field emulsions. The present paper deals with the factors responsible for the formation of emulsions. This will be followed by another dealing with methods now utilized for dehydrating oil-field emulsions, and by a third dealing with the physical chemistry involved in the formation and resolution of such emulsions.

Jan 1, 1925

By Robert M. Becker

A thick-wall cylinder solution applicable to the evaluation of anisotropic elastic parameters is derived for the interpretation of stress relief data. For a restricted class of problems, a special relationship among certain orthotropic moduli yields stress distributions for the plane orthotropic problem that are identical to the corresponding isotropic case. A ring or hollow cylinder with these specialized anisotropic properties subjected to uniform radial loads is one of the problems in this class. Consequently, known stress solutions are used to develop the strains and displacements for a specialized orthotropic thick-wall cylinder under uniform pressures. The results are consistent with anisotropic equations used in the evaluation of in situ rock stresses.

Jan 1, 1968

By W. L. Acherman

The Bureau of Mines found the chemical and galvanic corrosion behavior of the TZM and molybdenum-30 tungsten alloys to be generally equal or superior to that of unalloyed molybdenum in many aqueous solutions of acids, bases, and salts. Notable exceptions occurred in 1 [N] nitric acid, where both alloys corroded appreciably faster than molybdenum. In mercuric chloride solutions, the TZM alloy was susceptible to a type of crevice corrosion which was not due to differential aeration. The alloys were usually not adversely affected by con-tact with dissimilar metals in galvanic couple experiments, but the dissimilar metals sometimes corroded galvanically. Both alloys were resistant to substitute ocean water spray at 60° C.

Jan 1, 1968

By D. A. Doughty

The Bureau of Mines developed two methods for determining iron II and iron III in 2- to 5-mg samples of coal using electron paramagnetic resonance (EPR) spectrometry. One method used solid coal samples; the other method used aqueous solutions. The method using solid samples was more simple, technically, but required the use of X-ray fluorescent analysis, or another independent method, for determining total iron in the samples, and the results were subject to some uncertainty. The method using aqueous solutions appeared capable of greater certainty and did not require additional methods of total iron analysis but was more involved procedurally. The coals analyzed were found to contain much more iron II than iron III.

Jan 1, 1973

By M. H. Kline, T. J. Ballard

"INTRODUCTION The Cranberry magnetite deposits occur in pre-Cambrian granite-gneiss in a belt extending from 3 miles southeast of Cranberry, N. C., to about 6 miles southwest of Magnetic City, Tenn. The belt forms a curve, elongated to the north, approximately 26 miles in length.The Bureau of Mines investigation has been confined to the eastern part of the belt, comprising the area from Fork Mountain, Avery County, N. C., to the Hcupscup Knob prospects in Carter County, Tenn.The deposits were worked at least as early as 1820. The Cranberry Iron & Coal Co. and its successors operated the Cranberry mine intermittently for about 50 years until 1930, when operations were abandoned.The magnetite rock is amenable to concentration. Numerous laboratory tests and pilot-mill operations have proved that a high-iron, and low-phosphorus concentrate can be obtained by fine grinding and magnetic, separation, the quality of the concentrate depending upon the extent of grinding. The principal objectives of the Cranberry project were threefold.The primary consideration for beginning exploration of the deposits was the need for developing additional deposits of high-grade iron ore during the war and for replenishing the war's depletion of iron-ore reserves for the peacetime economy. The emergency did not permit logical sequence bf development, and it was necessary to begin drilling before the geophysical survey was completed. The first drilling was begun at the Cranberry mine; and the holes were located from the geological data, coordinated with the position of the mine workings."

May 1, 1948

By J. A. Cavallaro

The heats of formation of anhydrous barium carbonate (witherite), strontium carbonate (strontianite), and lead carbonate (cerussite) were determined by solution calorimetry. The solution mediums were hydrochloric acid for barium and strontium carbonates and perchloric acid for lead carbonate. The heats of formation at 298.15° K are as follows: BaCO3 -297.5 ± 0.8 kcal/mole; SrCO3 -294.6 ± 0.5 kcal/mole; and PbCO3 -168.0 ± 0.3 kcal/mole.

Jan 1, 1966

By K. C. Dean

A semiquantitative test for the presence and identification of cesium and rubidium in rocks, clays, and mineral waters has been developed by the Bureau of Mines. The test can be used in the field, as a guide for the prospector, geologist, or mining engineer engaged in location or development [w]ork. It comprises two simple spot tests of a solution prepared from the [m]ineral sample. Phosphomolybdic acid, added to a drop of the test solution, [d]etects cesium, rubidium, and potassium in quantities as low as 60 parts per [m]illion. Silicomolybdic acid, added to a second drop of test solution, enables the operator to distinguish between cesium and/or rubidium and potassium. Test procedures, equipment requirements, and limitations of the method are described in this report. Cesium and rubidium were discovered in 1860 and 1861 by Bunsen and Kirchhoff with a spectroscope. The elements usually occur together, particularly in granite and granitic pegmatites. Rubidium does not occur as an essential constituent of any known mineral, yet it is found as a minor element in so many minerals that rubidium is 16th in abundance in the earth's crust. Cesium, which ranks as the 37th most abundant element, is the principal component of pollucite and a minor element in a wide variety of minerals.

Jan 1, 1960

By M. Carrales

This Bureau of Mines publication presents short-range projections of domestic liquid hydrocarbon production through 1980. Appraisal of future crude oil production was made by evaluating the relationship between primary and enhanced oil recovery and the total crude oil producing trends in each of the oil-producing areas of the United States. Future natural gas liquid production was generally estimated by projecting historical production. Estimates of production were prepared for each of the oil producing areas and summarized for the Petroleum Administration for Defense (PAD) districts and total United States. From 1975 to 1980, crude oil production for the conterminous United States is expected to decline from 7.8 to 6.4 million barrels of oil per day (BOPD), and it is expected to increase from 8.0 to 8.2 million BOPD for the total United States. However, these estimates do not include additional production expected from the Elk Hills field in California and the Yates field in Texas. If included, 1980 production for the conterminous United States would be 6.7 million BOPD and 8.4 million BOPD for the total United States.

Jan 1, 1977