Search Documents

By E. J. Lintner

This paper is one of a series being prepared by the United States Bureau of Mines describing clay and shale mining and crushing methods and costs at various operations throughout the United States. These papers are designed to disseminate technical information regarding methods used. The cost tabulations represent local operating expenditures only and not total production costs. It is recognized that publication of total production costs may, in many instances, cause embarrassment to the individual operator as well as to the industry as a whole. On the other hand, it is essential to the technical discussion and study of methods employed to consider operating costs. The attention of the reader is specifically called to this differentiation in order that no misunderstanding of the scone of the cost tabulations shale ensue. The open-pit recovery of clay and shale is a comparatively simple operation in comparison with underground mining; nevertheless, it represents an appreciable factor in the cost of manufacture.

Jan 1, 1936

By C. H. Fisher

Sulphuric acid of various concentrations has long been used as a reagent in the determination of olefins and aromatics in hydrocarbon oils4 such as gasoline, kerosene, and neutral oils from coal-tar distillates. Despite its long use, however, there is no general agreement as to optimum conditions and concentration of acid, and numerous methods and modifications have been recommended. In most cases, treatment of the neutral oil with 80 to 90 percent sulphuric acid, followed by distillation to the original endpoint to remove olefin polymers, is recommended for the estimation of unsaturated hydrocarbons. The distillate thus obtained is taken as olefin-free oil and used in later stages of the anlysis. Aromatic hydrocarbons generally are determined in the olefin-free oil by suphonation with more concentrated acid (96 to 100 percent and fuming sulphuric acid are recommended), the hydrocarbons not attacked and removed as water-soluble sulphonic acids being considered as saturated hydrocarbons. In some cases the saturates are examined further by differentiating between cyclic (naphthenes) and acyclic hydrocarbons (paraffins), Generally this is achieved by physical methods, although strong sulphuric acid is known to react preferentially with some types of saturated hydrocarbons. It was the purpose of the present work to make a general study of this type of analysis and to investigate the reactions of hydrocarbons under conditions often used in analyses that employ sulphuric acid reagents. Since previous work is not in good agreement, the optimum concentrations of acid for the different stages of the analysis were determined. Several sulphuric acid methods previously recommended and new modifications were compared, two synthetic solutions being used as the reference oil. The results obtained are presented below under separate headings.

Jan 1, 1937

By Graham W. Marks, Clyde A. Bridger

"INTRODUCTION An electrolytic process for the preparation of metallic cobalt has been developed recently in the Bureau of Mines Experimental Station at Boulder City, Nev. Chemical analysis shows this cobalt to contain impurities in small percentages, chief of which is nickel. It is desirable to be able to determine these impurities spectrographically. This report is concerned with a procedure for the spectrochemical determination of nickel in cobalt.Previous spectrographic work on cobalt was done by Breckpot and Mevis,/ who used the method of homologous pairs of lines. However, it was felt that a more detailed investigation was needed, employing the method of internal standards.ACKNOWLEDGMENTWe are indebted to B. G. Knickerbockor and his staff at the Boulder City, Nev., station of the Federal Bureau of Mines for their cooperation, and particularly to Richard W. Lewis and Robert G. Sanderson, who prepared nickel-free electrolytic cobalt for us."

Feb 1, 1948

By J. B. Vander Sande, L. C. Rainey, P. Bolsaitis, B. Dirsa

"The structure and composition of silica-rich particles recovered by lavage from the lungs of three active miners with different medical histories were studied using high-resolution electron microscopy and chemical microanalysis. The results arc compared to the similarly determined structure and composition of respirable-size mineral particles obtained from roof-bolter dust-box samples from two coal mines of widely different bulk quartz concentrations. The results show that the lungs of the miners contain silica-based particles with structures not found in the mine samples. Also, the particle structures and compositions found in the macrophages were different in each of the miners. The rau.lu suggest the possibility that intracellular processes may affect the susceptibility of individuals to silica-induced pneumoconiosis. The cytotoxic and fibrogenic potentials of mine dusts result from the activity of their individual components. Whether this effect is additive or even mass (i.e., dose) related is questionable and has been the subject of many investigations. Particle size and size distribution of various constituent minerals, the surface structure and properties of individual particles, and the self-cleaning capability of the lung (i.e., the capacity of the macrophage system) may, among other variables, affect the pathogenic changes induced by dusts lodged inside lungs. Extensive epidemiological investigations conducted on miners from different coalmining districts, where equivalent dust exposures have been shown to result in vastly different frequencies of lung disease incidence, also confirm this hypothesis (1) In a recent study, Ferrer et al. (2) used energy-dispersive X-ray analysis (EDXA) to investigate the inorganic element content in pleura and lung in reference, silica exposed non-pneumoconiosis, and silicotic populations. Constant depositions of silicon and calcium were detected in visceral pleura, parietal pleura, and lung of the refence group and in visceral pleura and lung of the exposed non-pneumoconiosis and silicotic groups. Comparison of the silicon content in pleura between silicotic and exposed non-pneumoconiosis subjects showed a nonsignificant probability of difference, whereas there were no differences with respect to the silicon content in lungs."

Dec 1, 1995

By Walter Pajalich

This Bureau of Mines report is a study of the organizational framework of the ferrous scrap industry, of the products produced, and of the factors affecting the consumption of ferrous scrap by the steel industry. Consumption data from 27 major iron and steel firms in the States of Illinois, Indiana, Iowa, Michigan, Minnesota, and Wisconsin during the period between 1957 to 1962 were grouped by type of iron and steel furnace production facilities to determine consumption pattern for various grades of scrap in comparison to ingot production, hot metal consumption, and home scrap generation. Grades of scrap affected by changes in scrap consumption were determined, and the pattern that emerged was analyzed. Correlation of scrap demand and its effects on scrap prices based on price of scrap receipts of No. 1 heavy melting scrap and No. 2 bundles in the Chicago area for the years 1957 through 1962 indicated that demand trends do not always affect the price of scrap, Past and present technological advancements in steelmaking processes are discussed, and their effects on the scrap industry are analyzed.

Jan 1, 1967

By H. H. Schrenk, Carlton E. Brown

"The purpose of this paper are (1) to present a broad picture of the recognized methods of measuring the various forms of atmospheric pollution; (2) to evaluate the significance of such measurements; and (3) to suggest suitable methods for obtaining comparative information on the concentration of contaminants in city air.The atmosphere (the gaseous envelope surrounding the earth) consists of a mixture of gases. These gases and their usual proportions are:4/The volume of water vapor in the atmosphere ranges from almost zero (in very cold weather) to about 5 percent arid averages about 1.2 percent.Strictly speaking, any other substance in the atmosphere or an excess of any of the substances mentioned (with the possible exception of water) is a contaminant. Needless to say, there are many contaminants in the atmosphere.In accordance with their physical state, contaminants may be classified as gaseous or particulate, and the latter may be classified as solid or liquid matter. Particulate matter, especially when dispersed in some medium such as air or some other gas, sometimes is referred to as dispersoid, and the complete system of gas and dispersoid is referred to as aerosol.All substances on the earth are potential sources of atmospheric contaminants. Combustible materials (particularly fuel for heating and power), sea water, earth or soil, metals, and animals (including man) are some of the important sources of contaminants.Ordinarily gases are produced by chemical processes, whereas dispersoids are produced by both chemical and physical processes. There are two general dispersoid-producing processes: (1) Condensation, in which molecules join to form larger units or particles, and (2) disintegration, in which large units are reduced to the particulate range (which for the purpose of this article may be considered to be from 100 microns, or 1/254 inch, down to molecular size) by such processes as crushing, grinding, abrading, and atomizing.“Condensoid"" is a convenient term for dispersoids formed by condensation, and ""disintegrasoid"" for those formed by disintegration. Solid condensoids are sometimes called ""fume,"" solid disintegrasoids ""dust,"" liquid condensoids ""fog,"" and liquid disintegrasoids ""mist.""5/"

May 1, 1942

By C. M. Paiencia

The Bureau of Mines studied the potential availability of primary antimony (Sb) from demonstrated resources in 21 mines and deposits in market economy countries (MEC's). Twelve of these properties were evaluated as producers and nine as non- producers. The 21 studied properties contain 499,600 mt Sb as demonstrated resources, of which 304,000 mt is recoverable as antimony metal; another 973,500 mt Sb is contained in inferred resources. Recoverable antimony from demonstrated U.S. deposits is only 10,700 mt, just 3.5 pct of the MEC total. Domestic production of primary antimony from operating mines has averaged only 561 mt/yr over the 10-yr period 1975-84. This represents just over 5 pct of total U.S. consumption of primary antimony, which averaged 11,081 mt/yr during the same period. The United States will thus continue to rely on imported ores andlor concentrates, antimony oxides, and metal to satisfy domestic industrial requirements. At production costs up to $1.15/lb Sb, 110,000 mt of refined antimony is potentially available from 10 of the 21 studied properties. At $2/lb, 294,000 mt Sb is available, and at $3/lb, the total rises to 304,000 mt Sb available from all evaluated producers of refined antimony.

Jan 1, 1986

By Thomas A. Morgan

The distribution of stress adjacent to each of 25 mine openings was determined by the borehole stress-relief method in the FMC Corp. Westvaco trona mine at Westvaco, Wyo. The purpose of the stress determinations was twofold: First, to study the effect on these distributions of various factors such as opening shape, stress level, and loading history; and second, to estimate the distribution of stresses adjacent to extensive high-extraction (85 to 100 percent) areas. Stress distributions in areas of low average stress correspond closely to the theoretical distributions based on elastic theory. However, in areas of high average stress, the stress distributions are of a type associated with plastic failure. The stresses adjacent to a mined-out area supported by remnant pillars were significantly higher than the stresses adjacent to another area in which the remnant pillars were removed.

Jan 1, 1965

By William J. Wuest

This U.S. Bureau of Mines report presents an overview of ground control considerations associated with floor heave. Factors affecting heave, such as in situ stress, floor characteristics, and mine geometry, are described. Floor-displacement monitoring and data analysis methods are outlined. Finally, floor heave remediation is discussed. The remedial techniques are divided into four categories: mine maintenance, supplemental support, mine structure, and techniques for multiple-seam operations. Other subjects covered in the report include laboratory and in-place testing of floor rocks, U.S. and international case studies, effects of mine layout, determination of excess horizontal pressure, and types of heave failure. The emphasis of this report is on practical considerations; theoretical discussions are kept to a minimum.

Jan 1, 1992

By O. C. Blade

This report on the properties of motor fuels sold through service stations in the United states was made in accordance with a cooperative agreement between the American Petroleum Institute and the Bureau of Mines of the United states Department of the Interior. This paper is a continuation of a series made in cooperation with the Coordinating Fuel Research (CFR) Committee of the Coordinating Research Council (CRC). Inc. The first of this series of reports presented data on motor gasolines sold during the winter of 1935-36, and succeeding reports described motor gasolines sold during the summers and winters to and including the summer of 1941. No reports were made on motor gasolines sold during the winter of 1941-42 and during the summer of 1942. However, starting with the winter of 1942-431' the semiannual reports were resumed.

Jan 1, 1950

"INTRODUCTION Early in 1936 the Interstate Oil Compact Commission and other groups interested in forecasts of demand for petroleum requested the Bureau of Mines to make a physical inventory of crude-oil stocks in the United States, Accordingly, the 74th Congress appropriated funds for conducting such a survey during the fiscal year ended June 30, 1937. In the discussions and hearing 2/ relative to the need for the survey, the opinion was expressed that crude oil held in storage for long periods had lost so much of its gasoline content that the economic significance of total stocks should be discounted materially. Therefore, a primary objective of the survey was to make a physical inventory of the crude oil held in storage above ground and to determine the quantities and characteristics of the light fractions contained in the various stocks."

Sep 1, 1938

By John E. Miller

A high accuracy Burnett apparatus for use at 12,000 psi and 0° to 65° C has been constructed at the Bureau of Mines Helium Research Center. The apparatus is patterned after Burnett's original apparatus, but the working pressure is much higher and elastic distortion can be essentially eliminated. An operating procedure to permit faster experimental measurements is suggested.

Jan 1, 1967

By W. E. Lamont

The Federal Bureau of Mines, in cooperation with phosphate companies in the Florida land-pebble area, made a comprehensive study of the waste clays, or "phosphate slimes," produced in the mining of phosphate rock in Florida. These slimes represent a significant ecological problem and a major deterrent to effective land recovery in the phosphate-mining areas. Physical, chemical, and mineralogical studies were made of slime samples submitted by 15 of the 16 plants in Florida in an effort to identify factors that prevent successful consolidation of the slimes and subsequent recovery of the mined lands. Results of these studies indicated that the clay mineral attapulgite, a hydrated magnesium silicate, was primarily responsible for the very poor settling characteristics of the slimes, and that the quantity of attapulgite in the slimes effectively controlled the settling rate, pulp density of terminal solids, viscosity, percent solids of filter cake, and flocculant requirements.

Jan 1, 1975

By E. D. Gardner

This paper is a progress report on the study of mining methods and costs in the western United States and summarizes that part of the work pertaining to the undercut block-caving method of mining. Ore is mined on a large scale exclusively by the undercut block-caving method at the following six mines in the western United States: The Morenci branch of the Phelps Dodge Corporation, Morenci, Ariz.; the Ray mines of the Nevada Consolidated Copper Co. at Ray, Ariz.; the Inspiration Consolidated Copper Co. at Inspiration, Ariz.; the Miamo Copper Co. at Miami, Ariz.; the Ruth mine of the Nevada Consolidated Copper Co. at Ruth, Nev.; and the Consolidated Coppermines Corporation at Kimberly, Nev. The undercut block-caving method is also used at the mine of the Andes Copper Mining Co. at Potrerillos, Chile.

Jan 1, 1930

By G. L. Gates

The Bureau of Mines studied the scales formed in producing wells in the Wilmington field, California. The scales were primarily barium sulfate and resulted from the mixing of injected sea water and formation waters; there was excess sulfate in the injection water and the formation waters contained appreciable barium. After breakthrough, the produced brines were supersaturated with barium sulfate. Laboratory tests indicated that barium sulfate precipitated quickly When the supersaturated brines were agitated with crystals of barium sulfate and fairly rapidly when more sulfate solution was added. Precipitation occurred slowly on standing or under nonturbulent conditions. Both the apparent and equilibrium solubilities of barium sulfate in these brines were determined and compared with equilibrium solubilities in distilled water and sodium chloride solutions.

Jan 1, 1965

By J. Sottile, J. L. Kohler

Component failures in the electrical control circuits of mining machines account for a large percentage of the total downtime of the machine. Once a failure has occurred it is always a tedious and usually a time-consuming task to locate the failed component. Moreover, the pressure to quickly locate the cause of a delay can lead to compromises in safety. Thus an onboard diagnostic system, essential for an automated machine, would be a very useful addition to existing machines. This report details U.S. Bureau of Mines development of a generic procedure for synthesizing diagnostic systems for electrical-control-circuit failures in mining machinery. A continuous mining machine is used as the testbed to illustrate the application of the developed methodology. Substantive differences among mining machine control circuits made it impossible to achieve a generic diagnostic system, but a generic approach for the synthesis of the diagnostic system was possible. As the research progressed, it became apparent that an algorithmic approach was better than an expert- system-based implementation. A prototype system was constructed and used to evaluate the diagnostic system. Prototype implementation issues are also examined.

Jan 1, 1993

By A. C. Richardson

The mine of the Porter Coal Co. is located at the town of Porter in the northwestern part of Jefferson County, Ala., about 20 miles west of Birmingham. The operations in this mine are confined to the middle and bottom benches of the Mary Lee bed. The coal from the Porter mine is handpicked and washed before being placed on the market. The handpicked lump coal and the washed egg and nut coal are sold chiefly as domestic and steam-raising fuel. The coal finer than 1 inch is washed in 2-compartment jigs and utilized in the manufacture of metallurgical coke. The coal company has found that, when coal ranging in size from 1 to 0 inch is washed in jigs, a considerable amount of high-ash material finer than 3/16 inch remains in the washed coal. This paper gives the results of an investigation which was conducted for the purpose of determining the washing characteristics of the through 3/16-inch raw coal and the extent to which the ash might be reduced by means of coal-washing tables. This investigation has been made in connection with an extensive study of the coal-washing problems now being conducted by the United States Bureau of Mines and the University of Alabama, with the cooperation of the coal-mining companies of the State.

Jan 1, 1933

Despite modest improvements in the performance of domestic interest rates and gross national product,1 fixed investment in domestic producers' durable equipment continued to weaken during the second quarter of 1982 and declined at a 12.8 percent annual rate compared with the first quarter.2 Large declines occurred during the second quarter in expenditures on many of the major mineral-consuming industries such as aircraft, computers, agricultural and construction machinery and mining and oil field equipment. These data appear to be consistent with the low level of business investment plans for 1982 reported in the DOC's Bureau of Economic Analysis survey of expenditures on new plant and equipment.3 Domestic and foreign industrial production and mineral industry production activities continued to decline in the most recent period because of weak demand conditions (Tables 1 and 2). The U.S. mining production index declined 7.7 percent between April and June as compared with 1.2 percent for total U.S. industrial production (Table 1).

Jan 1, 1982

By George L. Gates

It is generally recognized that if the lose and contamination of the fluid content of a core specimen from an oil- and gas-bearing formation in a well were eliminated, the value of core analysis would be increased greatly. In an effort to obtain uncontaminated cores, extensive field tests were carried out in the Mercy field, San Jacinto County, Tex., with the Carter pressure core barrel and an oil-base drilling fluid having very low rates of filtration as measured by the standard A.P.I. drilling-fluid filter teat. A tracer was added to the drilling fluid filter test. A tracer was added to the drilling fluid to provide a means for quantitatively measuring the volume of oil filtrate in the cores. Unfortunately, as stated in the report on the Mercy tests, very little oil nand was penetrated in coring the well; and because the performance of the pressure core barrel was not entirely satisfactory, the tests did not provide a complete answer to the question: Does a filtrate from an oil-base drilling fluid enter cores., and how does it affect the results of the core analyses?

Jan 1, 1950

By J. A. Taylor, H. F. Yancey

"INTRODUCTION Froth flotation as applied to coal is a process for separating desirable carbonaceous material from undesirable inorganic matter. In general, the feed must be finer than one eighth inch in size. The principal use of the process in the preparation of coal appears to be in the treatment of the fine sizes produced by breakage during mining and preparation.The Bureau of Vines in Information Circular 6714 has published general information on coal flotation, summarized investigative studies of the process, and described operating plants throughout the world with their tonnage, reagent consumption and operating costs.4ACKNOWLEDGMENTSThe present study of means for depressing pyrite and reducing ash ty froth flotation was conducted at the Northwest Experiment Station of the United States Bureau of Wines in cooperation with the College of vines. University of Washington, under the general direction of A. C. Fieldner, chief engineer, Experiment Stations Division, Bureau of Wines. Grateful acknowledgment is made for suggestions and criticisms received from W. H. Coghill, supervising engineer, U.S. Bureau of Mines Mississippi Valley Experiment Station, Rolla, Mo.; J. B. Morrow, and R. E. Zimmerman, of the Pittsburgh Coal Co.; and Dean Milnor Roberts and Prof. Joseph Daniels, of the College of Mines, University of Washington.FLOTATION AND DEPRESSIONA substance will tend to float if its surface attracts a gas film more strongly than it does a liquid film when both air and liquid are competing for this attraction. On the other hand, a substance will not float if its surface attracts a liquid film more strongly than it does a gas film. All theories of depression depend upon this fact. A wetted particle of floatable size most likely will be found in the tailings after the flotation process has been completed.The crux of flotation is the selective wetting of the undesirable material that tends to float. Two general methods 5, 6, 7 of depression are in use: One combines a chemical substance with the surface to form a wettable compound, and the other employs some colloidal or ionic substance which the surface selectively adsorbs, thereby forming a wettable surface."

Jan 1, 1935