Search Documents

By W. W. Adams

The safety record established by the coal-mining industry of the United States during 1934, although not as favorable as that for the previous year, was better than the record for any other year during the period 1930-34 for which complete figures covering fatal and nonfatal accidents at the mines are available. The number of accidents was 89.98 per million man-hours of employment compared with 86.74 for the year 1933, the latter being the lowest rate in any of the 5 years referred to. The rate was 105.60 for 1930, the first year covered by available data. Employment increased in 1934; the number of workers represented an increase of 8 percent over the year 1933, man-shifts of labor increased 16 percent, and the number of man-hours of labor increased 7 percent. The total number of man-hours of employment also exceeded the number reported for 1932, and was almost equal to the record for 1931.

Jan 1, 1936

By F. Matanzo

[Nine wire rope terminations were pull tested and fatigue tested to destruction to measure the termination efficiency and relative fatigue life. The terminations were selected on the basis off mine site visits and the specimen were assembled in a manner similar to industrial slings. To measure a termination's sensitivity to poor workmanship, both standard and modified assembly specimen were tested. Lang and Regular construction of the 6x19 and 6x37 class wire ropes were used in diameters of 13 mm (1/2 in.), 19 mm (3/4 in.), 25 mm (1 in.), 38 mm (1 1/2 in.), and 51 mm (2 in.). In static pull tests rope class, construction, and diameter interacted with the termination to influence the efficiency of the termination. In axial fatigue tests using only the 6x19 class rope, the effect of rope construction was negligible since failure was primarily dependent on the termination type. The Swaged Socket, a termination requiring a high capacity hydraulic press, gave the best overall performance in terms of efficiency and fatigue life. The short body length of the Zinc Poured Socket (RR-S-550) was attributed with the short fatigue life of this termination. The use of thermosetting resins as a replacement for zinc was demonstrated successfully for some socket designs. The fatigue life of the termination, expressed as a percentage of the fatigue life of the wire rope, was shown to be a guide for the retirement of the wire in these applications where the wiry' rope is primarily in axial loading.]

Jan 1, 1978

By Sidney Katell

This report covers the period January 1964 through December 1964; it is a continuation of the series that began with the publication of Information Circular 7516 in October 1949. Also, it is the sixth in a series of reports prepared under a cooperative agreement between the Bureau of Mines and the American Association of Cost Engineers. The agreement provides for the publication of an annual cost bibliography with the work load involved in the preparation shared equally. The abstracted articles, concerned with all facers of cost engineering in the field of chemical and petroleum. plants and related subjects, are from the following sources: 1. American Association of Cost Engineers Bulletin. 2. Bureau of Mines Information Circulars. 3. Bureau of Mines Reports of Investigations. 4. Chemical Engineering. 5. Chemical Engineering Progress,

Jan 1, 1965

By Sidney Katell

This report covers the period January 1964 through December 1964; it is a continuation of the series that began with the publication of Information Circular 7516 in October 1949. Also, it is the sixth in a series of reports prepared under a cooperative agreement between the Bureau of Mines and the American Association of Cost Engineers. The agreement provides for the publication of an annual cost bibliography with the work load involved in the preparation shared equally. The abstracted articles, concerned with all facers of cost engineering in the field of chemical and petroleum. plants and related subjects, are from the following sources:

Jan 1, 1965

By Jaffrey Y. Foley

Placer gold and platinum-group metals (PGM) In the Slate Creek area, northern Chistochina Mining District, are derived from silicified and carbonate-altered, Cretaceous-Tertiary (?) dikes and related mafic and ultramafic rocks. Gold In the placer deposits is also derived from Tertiary conglomerate and altered Jurassic-Cretaceous argilllte. The argilllte and Igneous bedrock sources show a unique Ag-Au-Cu-Hg-PGM association that Is attributed to a combination of magmatic, hydrothermal, and supergene processes. The bedrock and placer deposits contain a variety of gold silver-lead-copper and PGM alloys. The observed geochemical, mineralogic, and alteration features are consistent with current geological models for turbidite-hosted gold deposits. No economic gold or PGM lodes were Identified, but several areas warranting more detailed investigation were Identified. Conventional geochemical sampling and analysis of small sample splits weighing between 10 and 30 grams were shown to be unreliable as a consistent means of identifying gold- and PGM-bearing bedrock. Pan concentration of pulverized rock samples was shown to be a more effective, but still Imperfect means of Identifying gold and PGM source rocks. Geochemical data and mineralogic examination indicate that gold and PGM in potential lode sources are very finely and erratically disseminated, are chemically combined with other elements, and may not be entirely free-milling or amenable to simple gravity concentration.

Jan 1, 1990

By E. D. Gardner

From the standpoint of tonnage and dollar value copper is the most important nonferrous metal mined in North America. The opening of copper mines has had an important bearing on the development and settlement of many sections of the continent. The prosperity of many of the mining States or provinces depends directly upon the copper-mining industry. Normally, about 35,000 men are employed in the copper mines, mills, and smelters of the United States. The United States is the most important producer of copper among the nations; more copper is mined in North America than in any other continent, and for many years the United States alone produced about half of the copper of the world. During the last 10 years increasing production in South America and Africa has reduced the relative importance of North America and the United States.

Jan 1, 1938

By Martin J. Gavin

The results of investigations of the oil-shale resources of the United States were first published by the United States Geological Survey in 1915.1 Other reports 2 have followed. These reports, investigations by private individuals and corporations, and the beginning of the development of an oil-shale industry in this country have aroused considerable interest in the possibilities of these shales as a commercial source of hydrocarbon oils. The Bu- . reau of Mines bas appreciated these possibilities, and since 1916 one or more of its engineers have given all or part of their time to investigations relating to the treatment of oil shales. A short pamphlet a containing general information on the possibilities of oil shale in this country, particularly the shales of the Rocky Mountain district, has already been published. This pamphlet gives methods for assaying the shales of oil and ammonia and contains a bibliography for the use of those desiring to search the literature.

Jan 1, 1924

With IIT research institute as a cosponsor, this seventh mineral waste Utilization Symposium was funded by the Bureau of Mines through its Division of Mineral Resources Technology. Environmental scientists and engineers from five countries (Canada, Netherlands, Austria, England, Guatemala) besides the United States participated in the symposium, which was held Oct. 20-21, 1980, at the Chicago campus of IIT Research Institute. Of the 25 papers presented on the reclamation and recycling of mining and mineral wastes, municipal solid waste, industrial waste, and scrap metal, 21 are summarized herein.

Jan 1, 1982

By James H. Cobbs

The utilization of large diameter drilled holes for mine shafts seems to have had its beginning in Europe about 1850 (28) where the mining industries of Germany and The Netherlands first used drilled shafts. Recent shafts in softer formations of diameters as large as 25 feet and as deep as 1, 700 feet have been drilled in both The Netherlands and Germany. The first shaft drillers utilized cable tool or churn drilling techniques which limit both hole diameters and drilling speeds. Though some churn drilling of shafts is still performed, rotary drilling has been the dominant technique for many years.

Jan 1, 1973

[In presenting this list of permissible explosives and blasting devices, the Bureau of Mines desires to call attention to pages 17 and 23, outlining the conditions in use under which, and only under which, the explosive or blasting device is permissible. In view of publications recounting trade practice favoring the use of a blasting device without stemming, particular emphasis is placed upon condition 4 on page 17 and condition 2 on page 23. An explosive or a blasting device enumerated in the permissible lists of thin Bureau is not permissible in use unless it is properly confined with clay or other incombustible stemming.]

Jan 1, 1941

In presenting this list of permissible explosives and blasting devices, the Bureau of Mines desires to call attention to pages 17 and 23, outlining the conditions in use under which, and only under which, the explosive or blasting device is permissible. In view of publications recounting trade practice favoring the use of a blasting device without stemming, particular emphasis is placed upon condition 4 on page 17 and condition 2 on page 23. An explosive or y blasting device enumerated in the permissible Lists of thin Bureau is not permissible in use unless it is properly confined with clay or other incombustible stemming.

Jan 1, 1941

By Jeffrey Y. Foley

Chromite deposits along the Border Ranges Fault in southern Alaska were investigated by the Bureau of Mines. This report, part 1 of a two- part series, describes the deposits. Part 2 describes the mineralogy and the results of metallurgical tests. Fieldwork began in 1981 and continued through 1983. Ninety-four subeconomic podifom chromite deposits in eight mafic-ultramafic complexes were investigated. Previously unreported chromite deposits at Red Mountain on Kenai Peninsula, on Kodiak Island, and near Tonsina are described. Deposits range in size from less than a thousand tons to over 1.25 million tons of contained chromic oxide (Cr203). Grades range from about 5 to 10 pct chromite. Excluding all deposits more than 10 miles from tidewater or existing roads and all deposits containing only chemical- or refractory-grade chromite, about 2,200,000 tons of Cr203 are contained in 41 hard-rock deposits. A placer deposit contains an additional 556,000 tons. These 42 deposits constitute a subeconomic indicated and inferred reserve sufficient to meet the Nation's chromite demands for about 4 yr, or the metallurgical industry's demands for over 5 yr, at 1981 consumption rates.

Jan 1, 1985

By Staff

The goal of the U.S. Bureau of Mines diesel engine research program is to reduce exhaust emissions from diesel-powered equipment used in underground mines. This research has led to significant advances in aerosol measurement and to the development of more effective emission controls. This Information Circular contains reports of some of the presentations made at the Bureau's Information and Technology Transfer Seminar on Diesels in Underground Mines given in Minneapolis, MN, on September 29-30, 1992. The seminar emphasized the measurement and control of diesel particulate matter emissions. Topics covered include a discussion of the health issues associated with the use of diesel equipment underground, an overview of regulations, measurement techniques for diesel exhaust aerosol, levels of diesel exhaust pollutants found in mines, and modern emission controls. An appendix is included that contains a report describing the capabilities of the Bureau's diesel emissions research laboratory, two papers describing the effects of engine maintenance or: emissions, a paper describing the monitoring of carbon dioxide in mine air as an indicator of air quality, a glossary, and a list of abbreviations and acronyms.

Jan 1, 1992

By A. C. Fieldner

All technical facilities of the Bureau of Mines have been geared for more efficient use and conservation of mining equipment, developing plans for safety, improving the quality of coal through better methods of preparation, studying the problems of coal storage and utilization, and extending the uses of coal5/ for the war and postwar economy. The Bureau is now analyzing all of the coal purchased by the Army and much of that required by the Navy. Work on boiler feed water was doubled over last year to meet the increased demand made by the War Department for protecting vital boiler plants in many new camps and defense plants. Progress has been made in safely storing coal to reduce dangers of spontaneous ignition to a minimum and to preserve coking power. Mixtures of oil and coal to be used as a substitute fuel have been investigated. Technical service on the conversion of plants to other fuels has been given to government agencies and private consumers. The possibilities of making motor fuel,

Jan 1, 1944

By J. B. Zadra

The use of activated carbon for extracting gold and silver from pregnant cyanide solution and pulp has been investigated many times. The primary advantage of this use of activated carbon is that .the dissolved values can be recovered from slimy ore pulps or from slime portions of ore without settling and thickening or filtering. The loaded carbon is removed from the barren pulp, and the pulp can then be discarded. Activated carbon has been used recently in treating gold ores containing very little soluble silver. When the carbon was loaded with a suitable amount of gold, the silver load was negligible. The remaining problems concerned the removal of the gold from the carbon, the recovery of the gold as bullion, and the reuse of the unloaded carbon. As described in a recent report, a method that solved these problems was developed. The gold-laden carbon was leached with caustic sodium sulfide solution and the gold simultaneously recovered by electrolysis. Both the carbon and the spent solution can be reused. That process was applicable to gold-laden carbon only. It was not applicable to carbon carrying silver, because sodium sulfide does not leach silver from carbon but "fixes" it. It has been necessary, therefore, to develop a modified process for the removal or desorption of both gold and silver from loaded carbon. This modi¬fied process permits the use of activated carbon for extracting both gold and silver from gold ores carrying enough silver to have economical interest or in which silver may be the predominating value.

Jan 1, 1952

By C. H. Elder

Two degasification test boreholes were drilled to depths of 1,238 and 1,212 feet on Bureau of Mines property at Bruceton, Pa., as part of the Bureau's long-range coal degasification program. The holes provided detailed geologic information and geologic sections, which were correlated with regional stratigraphic cross sections prepared by the Pennsylvania Geological Survey. Gas content determinations and coal analyses were made on the Upper Freeport, Middle Kittanning, Clarion, Brookville, and Mercer coalbeds; gas content of the coalbeds ranged from 53 to 165 cubic feet per ton. Formation pressure and gas flow tests were conducted on selected coalbed intervals in borehole 1; formation pressures ranged from 292 to 473 psig. The middle Kittanning coalbed was hydraulically stimulated using very heavy gelled water, but gas production remained low because gel residue and formation water inhibited the flow of gas. Gas contents in the Clarion, Upper Brookville, and Mercer coalbeds were anomalously low owing to the proximity of porous sand-stones which act as reservoirs for gas migrating from coalbeds.

Jan 1, 1977

By R. A. Cattell

Every finding of the year's work, obtained under stress to meet present objectives, contributed to postwar needs, because the very nature and constitution of petroleum and natural gas require that research be conducted along the same general lines whether the results are applied in peace or war. More than 40 reports were submitted to the Petroleum Administration for War and others concerned with (1) evaluation of crude oils to determine their content of aviation-gasoline base stock, (2) evaluation of base stocks for blending with high-octane, synthetically manufactured components, (3) analyses of naphthas to determine their content of various types of hydro-carbons, such as benzene and toluene, and (4) the improvement of quality of marginal base stocks to meet future requirements of aviation gasoline. This upgrading of marginal stocks is being attained by selective distillation and chemical and catalytic removal of sulfur compounds. Asphalts were studied with respect to the characteristics of their various constituents in order to compound them, in the same way that aviation fuels now are being "built" to meet exacting requirements. The work previously initiated to give the industry fundamental data on thermodynamics of hydrocarbons progressed satisfactorily, and the heats of combustion of 10 hydrocarbons in the lubricating oil -range of petroleum were determined. Thermodynamic data requiring highly specialized techniques are so broad in application that their commercial usefulness is not yet fully appreciated.

Jan 1, 1946

By B. H. Clemmons, B. G. Saunders, R. H. Stacy

"INTRODUCTION This investigation was undertaken to determine the response of Birmingham (Alabama) red-iron ore to heavy-medium concentration. Specifically, the work involved a study of the efficiency of the process in separating coarse gangue diluents from the ore and an endeavor to evaluate the potential economic results. The investigative work was not intended, nor is it to be construed, to be adequately exhaustive in scope to enable immediate plant construction. Rather, the primary objective was to determine the grade of ore that could be produced by heavy-medium treatment and the resulting indicative or tentative benefits to be derived from such treatment. The latter, in turn, would determine the merits of the more exhaustive study that would be required for an ultimate decision on the heavy-medium treatment of the ores.The problem of avoiding excessive contamination of red-iron ores by shale and/or ferruginous sandstone has been before the operators of the iron mining industry of the Birmingham, Alabama, district for many years. Within the last two decades, increased mechanization of mining methods has increased this contamination to a considerable degree. In fact, general utilization of scraper loading and other mechanical methods of mining, in conjunction with small increases in the natural insoluble content of the ores, in some cases has actually resulted in the production of ""acid"" or excessively insoluble ore, where ""basic"" or excessively lime ores were produced formerly.The contaminating materials are derived largely from roof spells and natural parting seams in the ore, a condition that to some extent has been aggravated by the irregularity of the ore beds. The latter have been subjected to both primary and secondary folding in many places. Considerable faulting has taken place, also. In many localities these conditions render virtually impossible complete avoidance of ore contamination from the over and underlying sandstones and shales. However, in a few localities, where the ore beds are less disturbed and shale partings are absent, mining can and is being accomplished with relatively little dilution."

May 1, 1948

By M. A. Schellhardt

The Bureau of Mines has made periodic back-pressure tests on numerous gas wells in the Texas Panhandle field during the past several years to study the delivery capacities of the wells under different pressure and operating conditions and to determine the relationships between pressures and rates of delivery from gas wells.4/ However, information regarding the intake capacities of gas-well systems is meager, end in projects involving the flow of gas into porous-rock reservoirs it has been necessary to determine intake capacities of gas wells by trial. Accordingly the fundamental intake characteristics of natural-gas yells have been studied to develop a method for determining intake capacities under different wellhead pressures from data descriptive of the "output" or producing characteristic of the wells.

Jan 1, 1936

By O. H. Metzger

This is one of a series of capers being published by the Bureau of Mines on gold mining A the Western States. It describes the production of gold in the principal mining districts of New Mexico. The material was gathered red on a trip through tale State in the summer of 1936. ACKNOWLEDGMENTS The author acknowledges the aid and cooperation of mine operators in all parts of the State, who willingly contributed all information requested. Geological reports of the Geological Survey and the New. Mexico Bureau of Mince were drawn upon freely for information; credit to individual paper, is given in the text.

Jan 1, 1938