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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 John E. Shelton

The growing interest in beryllium as a structural material, and its in-creased use in recent years for atomic energy application, have led both government and industry to express concern over the inadequacy of the beryllium resources in the United States and the free world. Contemplated and proposed uses for this unique material will surpass the capacity of the domestic beryllium mining industry to supply raw material, which is presently extracted from relatively small deposits by hand sorting. The need for a simple beneficiation process for beryl ores has long been recognized by the Bureau of Mines, but to date no single process has proved satisfactory for treating deposits containing a sufficient tonnage of beryl ore to warrant commercial exploitation. As a part of the Bureau's continuing effort to develop an economical recovery process, this report describes flotation research on samples of beryl-bearing pegmatites from the George Roebling mine in Connecticut, and the Colony mine in New Hampshire. The study resulted in two methods of treatment to which the ores responded reasonably well.

Jan 1, 1961

By E. O. Wagner, A. W. Koth, V. F. Parry, J. B. Goodman, D. C. Gernies

"INTRODUCTION A commercial-scale pilot plant for gasification of lignite was completed by the Bureau of Mines at Grand Forks, N. Dak., early in 1945 as an extension of work on, gasification of low-rank coals initiated in a smaller pilot plant at Golden, Colo., during 1943. The development work on this plant was part of a program to make reducing gases from lignite for beneficiation of low-grade iron ores. The background of this project has been described in a previous report. 6/ The present report describes the major features of the large pilot plant, a record of experimental operating data during five runs totaling about 1,800 hours, .and results of experimental work on the small pilot plant at Golden during 1945.This project has created considerable interest because heretofore there has been little success in several attempts to gasify American lignites.Furthermore, the methed employed is a departure from conventional processes. Natural lignite is fed continuously into an externally heated annular retort and is converted into water gas by heat conducted through alloy metal walls. Because of the high thermal conductivity of metal, the rate of gasification is several times greater than can be obtained when employing refractory walls. The process has been developed to a part that leaves one major question unanswered. - ""How long will the alloy last under practical operating conditions?"" - and this question has aroussed the interest of the Coal Division of the Bureau of Mines in this new development.Owing to the high reactivity of the lower-rank fuels, the water-gas reactions proceed rapidly at medium temperatures of 1,650°F. to 1,800°F. These temperatures can be attained in a reaction zone heated by external means when the temperature of the retort does not exceed 1,900°F. while transferring from 6,000 to 7,000 B.t.u. per hour per square foot. Such rates are several times greater than can be attained through refractory walls as employed in the Didier-Bubaig 7/ and the Ahrens processes. 7/ Therefore, the investment cost of the gas generator per unit of capacity will be considerably lower for the higher-capacity process. However, the maintenance cost of metal vessels will be higher than that of refractory retorts, and this emphasizes the importance of large-scale operation to determine the life of an alloy retort under practical operating. conditions."

Sep 1, 1947

By E. D. Gardner

Placer mining is the mining and treatment of alluvial deposits for the recovery, of their valuable minerals. The method has been used principally for mining gold, but a large proportion of the world's production of tin, platinum, and diamonds and other gem stones and minor quantities of other heavy minerals have been won in this manner. In the United States, as in the world at large, gold has been the principal mineral obtained by placer mining. Minor quantities of metals of the platinum group are recovered with the gold in some localities. Important quantities of sapphires have been produced at placer mines in Montana, and tungsten minerals have been obtained on a commercial scale from placer deposits in California and Colorado. Other heavy minerals or gem stones, however, have not been mined to any important extent by this method in the United States. The search for placer gold and the working of the deposits when found have had much to do with the early development of the West. Placer mining has been gradually overtaken and surpassed in importance by lode-gold mining, until in 1932 less than a quarter of the country's total gold production was from placers or about an eighth, excluding Alaska. In 1932 about 76 percent of the placer gold produced in the United States was recovered by dredging. Although other forms of placer mining still are important, they have been declining for many years, as the richest and most readily mined deposits of gravel along the stream courses have been exhausted. During 1931 and 1932 there was a revival of small-scale mining, but few new deposits were discovered.

Jan 1, 1934

There has been a substantial increase in the use of rubber-tired front-end loaders in the mining industry in recent years. Concurrent with this increased usage, in the period of 1966 to 1970, there were at least 74 mining industry fatalities involving front-end loaders, or (on the average) in excess of one fatality per month. When the usage of front-end loaders by the construction industry and other industries, organizations, and agencies, such as the Government (i.e., Department of Defense), along with the uncounted numbers of serious, but non-fatal accidents, are included in the picture, the safety record for front-end loaders, of necessity, becomes a serious subject for study. There is an urgent need for attempts to be made to eliminate or reduce the number of safety hazards; to decrease the confusing diversity of controls designs found on present front-end loaders; to improve the maintenance and operating procedures; to formulate better personnel policies; to increase management and official awareness of the extent of the problem, in both industry and the Government; etc.; in order to decrease the number of accidents. Part of the problem may be traced to the fact that the operator of a front-end loader is frequently designated a "heavy equipment operator." This implies that he is automatically qualified to operate any model, of any manufacturer's, wheeled or tracked, front-end loader as well as many other types and classes of heavy equipment. Contrary to automotive practice, the complement of primary operating and emergency controls varies widely from model to model, as well as from manufacturer to manufacturer. Not only are certain controls present on one front-end loader model and absent on others, but there are significant differences in the modes of control operation, in the functions performed by superficially similar controls, in the location of the various controls, etc.

Jan 1, 1973

By R. V. Ramani

This report is volume 1 of an eleven-volume final report for a Grant completed by The Pennsylvania State University for the Bureau of Mines to develop a dynamic general purpose computer simulation model for underground coal mining. The simulator developed under the Grant has a wide range of possible applications in the design and evaluation of underground coal mining systems from the standpoints of health and safety, productivity, and mine environment. The Master Design Simulator consists of nine free-standing function-oriented subsystem models linked together into an integrated, comprehensive model of an entire mining system. The subsystems comprising the Master Design Simulator include geology and reserves, methane generation, roof support, subsidence, production, rail haulage, cost, water generation, and ventilation. This volume of the final report contains a statement of the purpose and scope of work of the Grant, and provides an overview of the Master Design Simulator with a brief description of each subsystem. Also included is a discussion of several areas of application for the simulator.

Jan 1, 1975

By J. W. Paul

The material that composes the roof in coal mines differs in strength according to variations in its physical nature and characteristics. Some material such as limestone and massive sandstone, (free from slits) and carbonaceous shale or bone, will often remain in place in narrow work without the use of timber or other means of support, but in wide places the use of supports becomes a real necessity. Roof material composed of shale, fire clay or small laminations of sandstone, or shale or sandstone interspersed with laminations of thin coal, presents conditions that call for timber support in both narrow and wide work. However, in narrow work such unstable roof material may be taken down until the strata assume an arch that is self-supporting for overlying firm strata such as a roof coal, a touch weather-resisting, shale, sandstone, or limestone. The proper support of the roof in roadways used for haulage or travel adds to the economy of operation by preventing delays in transportation and increases the safety of those who travel these roadways.

Jan 1, 1930

By Mark Davis

As a follow-on to previous investigations, reduced treatment levels for the optimum fire retardant/preservative system were evaluated. An impregnation of 3.5 lbs/ft3 of Fyreprufe followed by 3.5 mils of Albi 107A plus an Albi 144 top coat provides adequate flammability and flame spread protection. However, there is a significant loss in compressive strength at this retention level, particularly parallel to the grain. A pilot-size pressure impregnation cell was installed for use in treating larger quantities of wood. Based on the optimum fire retardant/preservative treatment system - Fyreprufe/ACC impregnation followed by Albi 107A/144 intumescent paint - a model treatment pro¬cess was developed, capable of handling 3 million board feet per year. Associated annualized costs per thousand board feet (K bd. ft.) for treating 12" x 12" timber were calculated to be: Impregnation: $-63.00/K bd. ft. Coating: $112.00/K bd. ft. A literature search was conducted to identify materials and techniques suitable for a localized stench warning system for heated mine timbers. Based on this review, a number of stench warning concepts were developed. Those based on surface coating were given a preliminary laboratory evaluation.

Jan 1, 1982

"IntroductionThe combined library facilities of the five universities in the Generic Technology Center for Respirable Dust, The Pennsylvania State University, West Virginia University, University of Minnesota, Massachusetts Institute of Technology, and Michigan Technological University, represent one of the most extensive and comprehensive collections of information on respirable dust research which is available in the United States. The Center encompasses two major medical schools, the Milton S. Hershey Medical Center at The Pennsylvania State University and .West Virginia University Hospital at West Virginia University, and includes national and international experts from such diverse disciplines as geology, geomechanics, mining engineering, mineral processing, electrical engineering, industrial engineering, mechanical engineering, material science, physics and several areas of medicine. In order to maximize achievements in research and facilitate early results application in the private industry, university, government and public sectors, a geographically dispersed Reference Center on Respirable Dust has been established at each of the affiliated universities. This network serves to encourage unity between the universities in the Center and coordination and communication with other entities who benefit from their research.Description of the Reference CenterIn this light, the goal of the Reference Center network is to identify at what location Information is available and to provide a means for others to access this information. It is especially necessary to have both ease of input and maximum retrieval capabilities available to all the research personnel in the Reference Center. At the same time, the service provided to the inquiring public must be complete and cost-effective. The Center's approach to realizing this goal incorporates advances in computerized and electronic searching of individual library holdings and the networking of major library and commercial search systems.The Reference Center uses the following means to achieve this goal. At each participating university, a hard copy collection ls maintained of the current respirable dust research in progress by that institution's personnel. Also, available. at each university ls a review of their past and present research on respirable dust. At each participating university a hard copy collection of annual status reports and of all publications produced by Center personnel for symposiums, national and international conferences ls maintained. A key word computer search capability ls available to participating universities. This computer search, by title, author and location, allows researchers to determine at which facility information is available, thus avoiding the tremendous expense and effort of housing all the information on respirable dust research under one roof. The Reference Center has access, through The Pennsylvania State University Libraries system and the libraries of other institutions, to a large number of data bases such as MEDLINE at the National Library of Medicine,"

Aug 31, 1989

By W. A. Calhoun

Progress made in a second and final metallurgical investigation made by the Bureau of Mines of near-surface Hawaiian bauxitic deposits from Kauai, Maui, and Hawaii Islands, and on a deeper deposit from Kauai, is reported. Previously reported Al2O3 extractions were increased by modifying conventional processes to fit the ore being tested. Increases in Al2O3 extraction were: Kauai, from 82.8 to 95.4 percent; Maui, 85.5 to 94.1 percent; and Hawaii, from 79.5 to 86.4 percent. Use of a "caustic-reduction sinter, leaching, and magnetic separation process" for Al2O3 extraction also produced an iron concentrate of commercial grade, except for titanium content. No successful method was developed for the recovery of a satisfactory titanium concentrate.

Jan 1, 1967

By R. R. Sayers

That the maintenance of proper air conditions is a most important factor in the control of occupational hazards is shown by the large amount of material presented each year through the technical journal's on the effects on workers of injurious dusts, gases, and variations in temperature and humidity.. SUMMARY OF RECENT LITERATURE ON EFFECTS ON WORKERS OF EXPOSURE TO DUSTS The subject of the control of dust and dust diseases continues to be a matter of serious concern in most of the industrial countries of the world, as indicated by the following summary of reports published in a number of foreign countries as well as in the United States. Australia. The Workmen's Compensation Act of 1920 for New South Wales3 provided for the promulgation of schemes for the compensation of workers dis- abled by silica or other dust. In 1924 the prevalence of silicosis and tuberculosis among Sydney stonemasons, quarrymen, sewer miners and rockchoppers was investigated by a Technical Committee of Inquiry, appointed upon the recommendation of the New South Wales Board of Trade. The findings of this committee were published by the Government in 1925. No scheme was promulgated by the Government and in 1926 the Act was amended limiting its scope to workmen disabled by disease caused by silica-dust. This was promulgated and gazetted on September 16, 1927, and applies to men working in sandstone as stonemasons, quarrymen, rockchoppers, and sewer miners in the County of Cumberland.

Feb 1, 1931

By L. E. Cardwell

This publication contains routine analyses and related source data for 377 natural gas samples from 19 States and two foreign countries. Of this total, 373 samples were collected during calendar year 1970. The remaining four samples were collected during previous years, but releases granting per-mission to publish the analyses were not received until 1970. All samples were collected as part of a continuous survey of the free world for occurrences of helium in natural gas. This survey has been conducted in the United States by the Bureau of Mines since 1917. In late 1965, the survey was expanded to include foreign gasfields. The analyses published herein were made by mass spectrometer and a special helium analysis apparatus, which are described in Bureau of Mines Bulletins 4863 and 576.4 Twelve previous publications have presented the results of 9,050 gas analyses prior to 1970. The first three, Bulletins 486,6 576,8 and 617,7 contain analyses and related source data on 5,218 gas samples collected from

Jan 1, 1971

By L. E. Cardwell

This publication contains routine analyses and related source data for 390 natural gas samples from 22 States and five foreign countries. Of this total, 385 samples were collected during calendar year 1969. The remaining five analyses are of samples collected during previous years, but releases granting permission to publish the results were not received until 1969. All samples were collected as part of a continuous survey of the free world for occurrences of helium in natural gas. This survey has been conducted in the United States by the Bureau of Mines since 1917. In late 1965, the survey was expanded to include foreign gasfields. The analyses published herein were made by mass spectrometer and a special helium analysis apparatus which are described in Bureau of Mines Bulletins 4863 and 576.4 Eleven previous publications have presented the results of 8,660 gas analyses made by the Bureau of Mines Helium Activity prior to 1969. The first three, Bulletins 486,6 576,6 and 617,7 contain analyses and related source

Jan 1, 1970

By W. P. Haynes

To evaluate the potential use of battery-powered vehicles, the Bureau of Mines studied the performance of a battery-powered truck propelled by a 9.6 kw dc motor in considerable detail under various driving conditions. Some of the factors investigated were: Gear ratios, payload (1,468 lb maximum), road grade, stops made per mile, and charging time. With the exception of some difficulty with brush wear, operation and maintenance of the truck was generally trouble-free. On range tests carrying an 868-lb payload a distance of about 50 miles at an average speed of about 19 mph in normal driving, the Bureau's battery-powered truck averaged 1.6 to 1.9 miles per ac kwhr input. Stop-and-go tests indicated that prospects for the use of battery-powered trucks in house delivery service within city limits are good; performance of the Bureau truck was sufficiently high for that type of service. The estimated power cost of 2.65 cents per mile while making 10 stops per mile was attractively low from the standpoint of fuel costs.

Jan 1, 1967

By David S. Brown

What troubles me so often about debates over the environment, which I have heard since I entered government in the late 1960's, is that the issues are so often presented as a false dilemma--the either-or fallacy in logic. The either-or fallacy allows only two possible choices: Either protect the environment or exploit it. In reality, however, there may be a few more options. The diverse, often competing, values that the Earth offers require us to weigh and balance those options through a range of policy options. A quality environment and economic growth and opportunity are not mutually exclusive. First, let me acknowledge that I support a set of resource values recognized in U.S. laws and deemed important down through history for the success of free, progressive, and secure societies: the importance of access to raw materials. Increasingly, however, mineral raw materials have been viewed at best as not particularly relevant to a sophisticated, technologic society, and at worst monstrously destructive of our natural environment. Both perceptions, in my judgment, are wrong.

Jan 1, 1989

By John D. Sullivan

The present article is one of a series which is being prepared by the Southwest Experiment Station of the United States Bureau of Mines in cooperation with the Department of Mining and Metallurgy, University of Arizona, Tucson, Ariz., of papers dealing with factors involved in the leaching of copper ores. A knowledge of the time required to dissolve the various copper minerals present in ores, as well as of the consumption of leaching reagents is very desirable, because with the decrease of the Nation's total tonnage of sulphide ores increasing attention is being given to the recovery of copper by leaching methods from low-grade disseminated ore containing both oxidized and sulphide minerals. As leaching has already been applied with success and profit, this study was undertaken to determine certain fundamental characteristics that are applicable to all ores suitable for leaching.

Jan 1, 1929

Heavy liquids have come into use in ore-dressing investigations, as they make possible the separation of an ore into its specific-gravity components. A paper containing a general dissertation on heavy liquids has been written by John D. Sullivan,4 and the practical application of heavy liquids is explained by Box and Crabtree5. Some heavy liquids become discolored after continued use, and the lack of transparency impairs their value. Since they are fairly expensive, reclaiming is desirable. This paper briefly discusses the preparation and care of some of the more common heavy liquids.

Jan 1, 1928

By Robert W. Waytulonis

Mining regulations pertaining to the use of diesel engines were solicited from foreign countries with mining operations by the Bureau of Mines. Responses were received from 27 countries; the information received and U.S. regulations were reviewed, and those parts pertaining to the use of diesel engines in underground mining were synopsized according to the following subject categories: types of engines permitted, testing and certification procedures, fuel quality specifications, emission control requirements, procedures and frequency of testing exhaust gases, mine air quality and quantity (ventilation) requirements, procedures for testing mine air quality and quantity, and noise standards. All categories except the types of engines permitted and testing and certification procedures are summarized in tables. Contacts are provided for each country to facilitate inquiries concerning regulation revisions or interpretation.

Jan 1, 1987

By W. I. Nissen

As part of its program to provide technology for reducing undesirable environmental impacts of mineral processing operations, the Bureau of Mines developed the citrate process for desulfurizing industrial stack gases that contain from 0.1 to 2 vol pet S02. In this regenerable flue gas desulfurization (FGD) process, S02 is absorbed from cleaned and cooled industrial flue gas with a citric acid-sodium citrate solution. The absorbed S02 is subsequently reacted with H2S to precipitate marketable elemental sulfur and regenerate the solution for recycle. Laboratory investigations of process parameters provided information for designing larger scale continuous operations. Information gathered from operation of two pilot plants, one at a copper smelter and one at a lead smelter, confirmed the laboratory results. Data were obtained for design and construction of a commercial-sized demonstration plant at the George F. Weaton Power Station, Monaca, PA. A preliminary operation of the plant was demonstrated, under a cost-sharing Bureau-industry contract. This bulletin describes the citrate process and gives results of the laboratory, pilot plant, and demonstration plant studies, as well as corrosion investigations.

Jan 1, 1985

By B. J. Moore

This publication contains analyses and related source data for 352 natural gas samples from wells and pipelines in 18 States and 5 foreign countries. All of the samples were obtained and analyzed during calendar year 1974 as a part of Bureau of Mines investigations of the occurrences of helium in natural gases of countries with free market economics. This survey has been conducted in the United States by the Bureau of Mines since 1917. In late 1965, the survey was expanded to include foreign gasfields. The analyses published herein were made by mass spectrometer and a special helium analysis apparatus, which are described in Bureau of Mines Bulletins 4862 and 576.3 The results of the investigation of the occurrences of helium are published annually to make the information available as soon as possible to the gas industry and the public in general. Sixteen previous publications have presented the results of 10,479 gas analyses prior to 1974. The first three, Bulletins 486,4 576,5 and 617,6 contain analyses and related source data on

Jan 1, 1975