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By B. J. CROSS., Henry Kreisinger, John Blizard, C. E. Augustine

This bulletin presents the results of 36 tests made on a 468-horsepower Edge Moor boiler fired with pulverized coal at the Oneida Street Station of the Milwaukee Electric Railway & Light Co., Milwaukee, Wis. The tests were made by the fuel section of the United States Bureau of Mines in cooperation with the research department of the Combustion Engineering Corporation. Illinois coal was used as fuel; the furnace, burners, and feeders were designed by the Locomotive Pulverized Fuel Co. The object of the tests was to determine what over-all boiler efficiency could he obtained with pulverized coal under various conditions of furnace operation and with coal of different fineness and moisture content. The investigation was thorough. The pulverized coal, as it was supplied to the furnace, was weighed in specially designed tanks placed on platform scales. Twenty-nine of the tests were of 24 hours duration, three of 16 to 18 hours, and four of 12 hours. All tests are reported excepting two-8 and 20-which had to be stopped abruptly, No.8 because a motor actuating the coal-feed screw burned out and No. 20 because of trouble with the feed pump. Tests 1 to 27, inclusive, were made with round burners and tests 28 to 3Rwith spreading burners. In the first nine tests a large excess of air was supplied in an effort to prevent the ash fusing at the bottom of the furnace. In tests 10 to 16 the supply of excess air was reduced in order to get a high efficiency, regardless of the slagging of ash at the furnace bottom. Tests 17 to 27 were made with a water screen about 10 inches above the bottom of the furnace, to make possible the burning of coal with a small supply of excess air without the ash fusing at the bottom of the furnace. Tests 28,29, and 30 were made without the water screen and with a small supply of excess air, and tests 31 to 38 with a water screen around the walls near the bottom of the furnace. Tests 32, 33, 34, and 35 were run with coarser coal than that used ordinarily at the plant. Tests 36,37, and 38 were made with undried coal.

Jan 1, 1923

By F. W. Wood

ORIGINAL experimentation in specially designed arc-melting furnaces and a comprehensive review of technical literature have helped with an understanding of electric arcs as used in metallurgical applications. Results relevant to the distribution of electric potentials and currents, temperatures, pressures, the consumption of electrodes, the identities of particles participating in electrical conduction, and the modes and mechanisms of discharge are presented and discussed. Present knowledge of high-current arcs is insufficient to test pertinent theoretical suggestions. However, the chief doubts concern the identities and the liberation or formation of current-carrying particles. It seems that either (1) novel formulations of existing concepts are needed, or (2) essentially new concepts must be recognized to explain observations. An analysis of the situation has led the authors to favor the latter possibility and to suggest the existence of supplementary conducting particles. The conduction of current by the streaming of charged agglomerates is postulated. Another outgrowth of analysis is an equation for the arc potential as a function of current densities in the arc. In lieu of conclusions, the potentialities of practical applications and specific needs for fundamental clarification are summarized.

Jan 1, 1965

By F. S. Crawford

Safety devices and guards are often looked upon as the last word in safety by the men around the shop or large industrial plant . However , thorough knowledge of the details of their jobs and of the dangers attending them are even more important . It should be unnecessary for all men to go through the experience of the first man to meet an unknown danger , but that appears to be about the only way by which many learn . Practically every danger connected with the job around a mine , blast furnace , steel mill , foundry , coke oven , cement mill , or other operation , was encountered for the first time by someone , and if he was fairly fortunate he either got hurt or just missed being injured and lived to tell his " budaies " how it happened; he spread the knowledge of that particular danger . Sometimes , but not often , a man can foresee a danger . If he could always be on guard and remember everything he had ever learned and also know everything that had happened to the other fellow , and then let that knowledge keep him aware of the dangers in his own immediate " job , " so that he would work the safe way for both himself and the other fellow , he would have what safety engineers call " safety consciousness . " Being safety conscious is a fine attribute , as it really means knowing all about one's job . A man who is really safety conscious is one of the best and most efficient workmen in the whole plant . The boss wants men of that kindmen who want to learn and who try to learn every little detail about their jobwhere there is danger of spoiling the heat or getting burned by hot metal in a steel plant or of loading rock instead of coal or ore in a mine . Such men know how to do whatever job they are on easily and with the least amount of hard work and at the same time get it done as quickly as possible with safety . A man who is safety conscious has to nearly all intents and purposes developed eyes in the back of his head , if he is in a big mill where there if something going on all around him . These eyes are not real eyes , but they are what might be termed a sixth sense which he has developed by his experience in the mill as well as in other dangerous work which he may have done before in other plants . There may be occasions when a man's safety consciousness will leave him for just a short time ; this is likely to happen when he is thinking about a quarrel he had with his wife which has not been cleared up happily , or perhaps when he has bought too many things on installment and with sickness at home

Apr 1, 1931

By R. Dell Davidson

This report contains the results of the work performed by Dayton T. Brown. Inc., Testing Laboratories, Bohemia, New York, under the Department of Interior, Bureau of Mines, Contract J0166089 entitled "Performance Testing of Air-Line Linking Components." The objectives of the program consisted of the following: 1. To conduct engineering tests that will provide data to recommend the performance criteria for air hose and piping connections. 2. To determine the requirements for restraining devices which are used to comply with MESA Health and Safety Standards 55, 56, 57,13-21.

Jan 1, 1978

The first metal-mine accident-prevention course was prepared and published in 1942-45 as a series of seven miners' Circular (Nos. 51-57). The scope of the course has been broadened, revised, and brought up to date and is being published as a similar series of seven miners' circular pros. 51-57, revised) on accident prevention in metal and nonmetallic mines. These circulars are: Accident Statistics (Miners' Circular 51), dealing with general statistics on accidents and injuries at metal and nonmetallic mines, including causes, costs, and the uses of investigations and reports of all accidents.

Jan 1, 1957

By Jr. Watts, B. K. Cantrell, D. H. Carlson, K. L. Rubow

"The use of diesel equipment in underground coal mines is controversial because ""whole diesel exhaust"" is regarded as ""a potential occupational carcinogen"" by the National Institute for Occupational Safety and Health (NIOSH). Threshold limit values (TLVs) are recommended for the gaseous pollutants; CO, CO2, NO, NO2, SO2, and some hydrocarbons emitted in diesel exhaust. There is, however, no TLV recommended for diesel exhaust aerosols (DEA) nor is there a standard method for sampling these aerosols.The University of Minnesota and the Bureau of Mines have collaborated to develop a personal diesel exhaust aerosol sampler (PDEAS) which utilizes size selective, inertial impaction and gravimetric analysis. During the field tests of this sampler, numerous air quality measurements were conducted in underground coal mines using diesel equipment. The objective of this report is to present these data and to assess the impact of diesel face haulage equipment on mine air quality.Air quality data were collected in four underground coal mines using continuous mining methods with diesel haulage equipment. Daily samples were collected at the section intake, haulageway, and on haulage vehicles. Both full-and partial-shift samples were collected using a variety of aerosol instruments, including the PDEAS and the micro-orifice, uniform deposit impactor (MOUDI) which sample the mine aerosol diesel exhaust fraction. Two of the mines were also monitored for the major gaseous constituents found in diesel exhaust CO, CO2, NO, NO2, and SO2. These measurements were made by either collecting bag samples for subsequent gas analysis or by Palmes dosimeters.The concentrations of CO, CO2, NO, NO2, and SO2, were well below regulated levels. The mine average DEA concentration determined by the PDEAS in the haulageway for the three mines surveyed using this instrument was 0.79 mg/m3, with a standard deviation of 0.19 mg/m3. DEA contributed 65% of the respirable aerosol, at this location. These results were the same as the mean DEA concentrations calculated from size distribution measurements obtained using the MOUDI. This was 0.78 mg/m3, with a standard deviation of 0.22 mg/m3."

Mar 1, 1992

By C. H. Riggs

THIS REPORT give's the results of a study of the central and south parts of the Cushing oilfield, including a description of the geology, a review of the production history, and estimates of oil reserves available by secondary-recovery methods. Each of the major producing zones of the field is treated separately. The report, which is one of a long series of field studies the Bureau of Mines has conducted over the past 40 years, was prepared to aid operators to increase oil recovery and to help prevent underground waste in the Cushing field, in the State of Oklahoma, and in the United States. The geology and production history are presented not as a review of past behavior of the Cushing field but rather to interpret the possibilities for increased oil recovery by future development of this and similar areas. The field, which is in the northwest corner of Creek County, Okla., was discovered in 1912 and developed during 1913 and 1914. For several years it, was one of the most important areas producing high-grade crude oil in Oklahoma. Although some oil has been recovered from each of 10 separate reservoirs, nearly 98 percent of the total recovery of oil in the area studied was from 4 major producing formations (table 1). Of these, only the Bartlesville [ ]

Jan 1, 1958

By H. G. Wolfhard

The mode of propagation of explosions through narrow passages is important for understanding flameproofed equipment employed in mines. Narrow channels have been used in this investigation that connected between a small explosion chamber and a large chamber containing fuel-air mixture. The oxygen index of the mixture in the small chamber was determined which caused an explosion in the outer chamber. Preliminary measurements have already been given in Bureau of Mines Report of Investigations 5457 and suggested that) flames do not pass through narrow channels. The hot, burned gases from the explosion in the small chamber, however, are able to ignite the mixture in the large chamber by a process of hot-gas ignition. Systematic measurements are reported in the present paper that cover the influence of channel length and diameter and the properties of the gas mixtures in the large chamber on the transmission of explosions. The influence of such properties as quenching diameter and flame temperature is also discussed. This paper concludes the work on this problem and presents a theory that describes in detail parameters that influence transmission of explosions through narrow channels. INTRODUCTION Flameproofed equipment in mines is usually provided with flanges. A gap between the opposing flanges allows ventilation and release of pressure. The safe gap width has been determined for a number of flange lengths by Smith4/

Jan 1, 1959

By H. M. Urban

This paper, one of a series being prepared for and published by the United States Bureau of Mines on methods and costs of mining at various mica mines in the United States, describes the methods now in use in the principal mica mines of the Southern Appalachian States. Those papers are designed to disseminate technical information regarding the methods used. The cost tabulations represent operating expenditures only and not total costs. It is recognized that publication of total costs might in some instances cause embarrassment to individual producers as well as to the industry as a whole. On the other hand, operating costs are essential to the technical discussion and study of methods employed. The attention of the reader is specifically called to this differentiation in order that no misunderstanding of the scope of the cost tabulations shall ensue.

Jan 1, 1932

By James E. Hill

In the course of exploratory drilling during World War II by the Bureau of Mines under the Strategic and Critical Minerals investigations Program, a problem arose as to the ultimate disposal of the drill core resulting from that program. The difficulties experienced in obtaining factual information to evaluate mineral deposits examined (during that program) influenced the Bureau in a decision to catalog and store the drill cores for future reference. Initially, the drill cores were stored at the nearest Bureau of Mines station that had space available for the purpose. Recently the Bureau stations at Minneapolis, Minn., and Denver, Colo., were designated as the locations of permanent drill-core storage facilities. Drill cores that are retained from Bureau of Mines mineral-exploration projects are stored at these two locations and are given preference in selecting cores for storage. Drill cores are accepted also for storage from other Government agencies, State agencies, private companies, or individuals on the basis of available facilities and consistent with the significance of the core in relation to Bureau of Mines objectives and national interest. Selection and acceptance of such drill core are determined by the Bureau of Mines. The drill cores stored at the two locations are available for inspection by any person having a legitimate interest in the mineral deposits represented by the cores. Approximately 1,850,000 feet of drill core can be stared in the facilities now available to the Bureau of Mines. Approximately 475,000 feet of drill care is stored or scheduled for storage at Minneapolis, Minn., and 240,000 feet of core stored or scheduled for storage at Denver, Colo. A list of drill core now in storage at the Bureau of Mines core-storage facilities at Denver and Minneapolis is included as appendix A.

Jan 1, 1957

By K. K. Kelley

The entropy values at 298.1° K. for the elements and inorganic compounds, on which sufficient data were available for calculation in 1931, were discussed in a previous publication (96).3 Since that time the specific beats at low' temperatures of many more inorganic substances have been determined, and considerable advances have been made in the realms of spectroscopy applicable to the determination of thermodynamic properties. Moreover, a critical study of the existing vapor-pressure data made by the author (98) furnishes entropy of vaporization results suitable for obtaining approximate values of the entropies of a number of gases from the entropies of the solids or liquids. Consequently, it appears worth while at the present time to supplement the former publication, giving the new values now obtainable and making such revision in the older values as the data warrant. The methods of calculating entropies were discussed in previous publications (96, 98) and will not be repeated here. ENTROPIES AT 298.1° K. FOR INORGANIC SUBSTANCES In the following pages, the same arrangement is followed as in the previous publication (96). All entropy values are expressed in 15° gram-calories per degree Kelvin per gram-formula mass of substance. The figures given for gases do not include the effect of nuclear spin, as is nearly universally customary at present. The estimates of accuracy in the case of the values obtained from heat-capacity data apply only to the existing measurements and to the necessary extrapolations as they are made. It is assumed usually that the substances are in such an energy condition at the lowest temperatures reached in the specific-heat measurements that the usual normal type of extrapolation may be made. No allowance is made for error in this assumption. The recent work on Gd2SO4. 8H2O and FeC13 illustrates the difficulties that may arise in obtaining the entropies of some paramagnetic substances. Also the data and calculations for such substances as CO, H20, and N20 show that the correct entropy is not obtained in all cases by indiscriminate application of the usual

Jan 1, 1936

By C. M. Harrer

Reconnaissance investigations were made of 129 iron occurrences in Arizona to determine their extent, attitude, and potential; character samples were analyzed to determine their quality and impurities; and pioneer metallurgical investigations were made on character samples to present their metallurgical problems. Some factors influencing past and potential western iron markets are discussed. The location, features, qualities, extent, and potential of iron occurrences and some associative resources--limestone and dolomite, coal, petroleum and natural gas, power, and water are discussed. The most abundant iron minerals are magnetite and hematite. The higher grade deposits are extensive contact-metamorphic or pyrometasomatic replacements of calcareous Paleozoic to Proterozoic rocks associated with intrusives. Large low-grade deposits of great potential are present as Precambrian taconite, semitaconite-, and jaspilite-like iron formations of magnetite-hematite. Iron occurs also as low-grade concentrations of magnetite in extensive alluvial deposits. Nonferrous metallurgical slags, nearly 100 million tons, are considered a potential source of iron. Various accessory elements are associated with the iron minerals and these pose metallurgical and economic problems.

Jan 1, 1964

By C. M. Harrer

Reconnaissance investigations were made of 129 iron occurrences in Arizona to determine their extent, attitude, and potential; character samples were analyzed to determine their quality and impurities; and pioneer metallurgical investigations were made on character samples to present their metallurgical problems. Some factors influencing past and potential western iron markets are discussed. The location, features, qualities, extent, and potential of iron occurrences and some associative resources--limestone and dolomite, coal, petroleum and natural gas, power, and water are discussed. The most abundant iron minerals are magnetite and hematite. The higher grade deposits are extensive contact-metamorphic or pyrometasomatic replacements of calcareous Paleozoic to Proterozoic rocks associated with intrusives. Large low-grade deposits of great potential are present as Precambrian taconite, semitaconite-, and jaspilite-like iron formations of magnetite-hematite. Iron occurs also as low-grade concentrations of magnetite in extensive alluvial deposits. Nonferrous metallurgical slags, nearly 100 million tons, are considered a potential source of iron. Various accessory elements are associated with the iron minerals and these pose metallurgical and economic problems.

Jan 1, 1964

By Robert H. Peters

Several significant problems associated with employee turnover among underground miners are described in this Bureau of Mines report. Although a vast amount of research has been conducted on turnover among employees in nonmining industries, there has never been an attempt to empirically investigate the causes of turnover among underground miners. This report presents the results of empirical research on employee turnover in other industries and describes and critiques the research methods that have been used to investigate turnover. Using the findings on employee turnover in other industries and known data about miners and the mining industry, a conceptual model of the factors that cause turnover among miners was generated. This model, which is expected to provide a basis for later empirical studies, is presented. Several recommendations for controlling miner turnover are also presented.

Jan 1, 1986

By J. G. Walters

Analyses of light oils produced from the fluidized carbonization of coal at 485°, 550°, 600°, and 660° C are presented. Tar vapors from 485 C fluidized carbonization were thermally treated at 600°, 700°, and .800° C, and the analyses of light oils produced by this treatment are also presented. Procedures were developed for analysis of coal carbonization light oil by gas chromatography to permit a more definitive analysis than can be obtained by the conventional distillation procedure. An increase in low-boiling olefins, benzene, and toluene, a decrease in low-boiling paraffins, and little change in the remainder of the aromatics was observed with increased temperature of carbonization.

Jan 1, 1965

By W. W. Fowkes

The Federal Bureau of Mines examined a low-temperature tar obtained from a small-scale commercial unit for carbonizing North Dakota lignite for products that might be important to the economic processing of the tar. Tie tar may be divided into three distinct parts: (1) Tar acids, 45 volume-percent; (2) tar bases, 1 volume percent; and (3) neutral compounds, 54 volume-percent. It has a boiling range of approximately 150° to 380° C. (the decomposition temperature) and yields 18 weight-percent as hard pitch. The tar distillate up to 365° C. may be separated as: (1) Tar acids, 48 volume-percent; (2) tar bases, 1 volume-percent; and (3) hydrocarbons, 51 volume-percent. The tar-acid distillate, boiling to approximately 265° C., was characterized in some detail; the neutral fractions and the tar bases were less thoroughly examined. In general, as might be expected of a primary low-temperature tar, the lower boiling fractions are less in quantity compared with the usual high-temperature tar. The homologous series of each major class appears to be rather complete, although some components are present in very small amounts. The tar is quite unstable thermally, and might be more conveniently processed by extraction methods rather than by distillation procedures. The neutral fraction of the tar is highly aromatic, and might be considered as base stock for the production of liquid fuels.

Jan 1, 1961

By Robert C. Merritt

This report describes laboratory as well as pilot heap leaching investigations of low-grade sandstone ores from Wyoming, New Mexico, and Colorado. Sodium carbonate-bicarbonate solutions containing sodium hypochlorite extracted up to 86, 54, and 16 percent U308 from Wyoming, New Mexico, and Colorado ores, respectively. Ammonium carbonate-bicarbonate solutions containing sodium hypochlorite were less effective at leaching these ores. Acid leach in replicate pilot plant testing resulted in U308 extractions of 96, 88, and 81 percent from the Wyoming, New Mexico, and Colorado ores. The development of cost-effective processes for extracting uranium from low-grade ore is essential to the assurance of a continuing domestic supply of uranium.

Jan 1, 1977

By Joseph Sabatini

This report, covering the period January through December 1975, contains abstracts of articles concerning all phases of cost engineering and economics for chemicals processing, raining, and other mineral industries. The abstracts are collected from the following sources: 1. Chemical Engineering 2. Chemical Engineering Progress 3. Chemtech 4. Coal Arse 5. Coal Mining and Processing 6. Combustion 7. Drilling 8. Electrical World 9. Engineering and Mining Journal

Jan 1, 1976

By R. A. Cattell

Progress of Bureau of Mines research related to oil and gas during the past fiscal year has been marked by the publication of more than 40 reports on the various phases of the work . These include papers dealing with the production of oil and gas , transportation of gas , chemistry and refining of petroleum , thermodynamic properties of hydrocarbons , and the processing and utiliza- tion of helium . As an additional service to Pennsylvania oil operators , a new suboffice was opened in Bradford , Pa . , during the year . With this addition , the work of the Petroleum and Natural Gas Branch of the Bureau of Mines is now conducted in two large stations , the Petroleum Experiment Station , Bartlesville , Okla . , and the Petroleum and Oil Shale Experiment Station , Laramie , Wyo . , and three field offices and laboratories at San Francisco , Calif . , Dallas , Tex . , and Franklin, Pa., and two suboffices, Wichita Falls, Tex., and the newly opened suboffice at Bradford, Pa. In addition, this Branch operates large-scale helium-production plants in Texas, Kansas, and New Mexico, and maintains ex- tensive helium-bearing gas reserves in Texas and New Mexico. All helium opera- tions are supervised from headquarters at Amarillo, Tex. A small headquarters staff is in Washington, D. C. A backward glance at the road traveled during the past several years by the Petroleum and Natural Gas Eranch of the Bureau of Mines brings out a general background for the events of the fiscal year 1949. Throughout the fiscal year 1945, the activities of the Branch were still mainly concerned with such war activities as making special field studies for the Petroleum Adminis- tration for War, finding ways of increasing rates of production, and supplying data pertaining to the manufacture of aviation and jet-propulsion fuels. A period of adjustment came in 1946, characterized by a turning from war to peace procedures and efforts to give wide distribution to technical facts ob tained in wartime research; also, there came a realization that the demands of war had broadened the horizons of research. This was emphasized in 1947, when a peacetime program was restored, based upon the long view of the Bureau's place as a research agency in oil and gas. Close attention was given to tech- nical detail in 1948, and emphasis was placed on maintaining a balance between the industrial need for technical knowledge and Governmental-research possi- bilities in the fields of (1) withdrawal of petroleum from natural deposits, (2) utilization of petroleum and its products, and (3) commercial utilization of helium. Studies of petroleum production and utilization and helium production and utilization are the normal functions of the Branch. These functions (sometimes expressed in different words) have been the mainstay of this organization since initiation of the work. The details of approach vary with changing conditions, but, fundamentally, the functions have been the same in both peace and war. The work of the past fiscal year has emphasized the advantages that accrue when Government and industry join in a wise use of technical and scientific knowledge gained through research. Outstanding evidence of the beneficial results of cooperative effort by the Bureau of Mines and various organizations is found in the following typical examples, the details of which are discussed in the body of this report. Working in close cooperation with operators along the Gulf Coast, the Natural Gasoline Association of America, and the National Association of Cor- rosion Engineers, the Bureau found, through field testing, that corrosion protection by means of chromates in high-pressure gas-condensate wells costs less than $1 per million cubic feet of gas produced. Laboratory experiments to measure the corrosion effects of carbonic and propionic acids on various steels and alloy steels gave data that will serve as guides in the selection of new. materials for the construction of well equipment to be tested by industry under actual service conditions.

Feb 1, 1950

By James Westfield

Following is a brief history of Bureau of Mines Division of Coal-Mine Inspection activities that have favorably effected health and safety and reduced Injuries at coal mines: The Federal cline Safety Code for Bituminous Coal and Lignite Mines of the United States was issued originally by the Director of the Bureau of Mines on July 24, 1946, after consulting with management and labor representatives of the coal-mining industry. The code has been used by Federal coal-mine inspectors while inspecting bituminous-coal and lignite mines for the existence of unhealthful and unsafe conditions and practices in these mines. A revised code was issued by the Secretary of the Interior on October 8, 1953, after further consulting with representatives of management and mine workers, and was incorporated in the 1952 and subsequent bituminous-coal wage agreements. The agreement of May 29, 1946, betweeen the Secretary of the Interior, acting as Coal Mines Administrator under authority of Executive Order 9728, and the United Mine Workers of America, covering bituminous-coal and lignite mines in Government possession, charged Federal coal-mine inspectors with the responsibility of making periodic investigations of the mines and reporting to the Coal Mines Administrator any violations of the Federal Mine Safety Code. Federal coal-mine inspectors also had temporary authority to close mines considered imminently dangerous, but authority under Executive Order 9728 was removed on June 30, 1947, when Government control of the mines was terminated.

Jan 1, 1962