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By Charles G. Howard

Accidents involving underground rail transport were analyzed to quantify the magnitude and the operational requirements for individual mine car braking systems. The results showed that the brake preventable accidents represent only 2% of the total underground fatal accidents and less than 1% of the total underground nonfatal accidents. In addition, the brake preventable accidents are expected to decline over the next decade. The costs of accidents involving deaths and Injuries were determined using various well accepted methods. The costs of a brake retrofit program for all operating underground coal cars were developed separately for small and large coal mines. Costs of retrofit brakes, new car brakes, maintenance, inspection and repair facilities were included in the esimates. The analysis showed that a retrofit program would not significantly increase safety, and that the program cost would greatly exceed the corresponding expected benefits.

Jan 1, 1979

Consumption and intensity of use trends for 12 metals, by industrial end use, were estimated for 1972 through 1982 by the Bureau of Mines and U.S. Department of Commerce. The trends were then forecast through 1993 using standard statistical methods. The intensity of use measure selected is the quantity of metal consumed per constant dollar output of a specific industrial sector. The metals studied were aluminum, chromium, cobalt, copper, lead, manganese, nickel, the platinum-group metals, tin, titanium, tungsten, and zinc. Average annual growth rates for the following 4 of the 12 metals increased from 1972 to 1982 as follows: aluminum, 1.00%; platinum-group metals (consisting of platinum, palladium, and iridium), 8.83%; titanium, 7.82%; and tungsten, 6.09%. Consumption for the remaining eight metals decreased at average annual rates ranging from 0.58% (copper) to 5.37% (manganese).

Jan 1, 1986

By Paul M. Tyler

Hafnium appears to be among the more abundant of the newly discovered elements . Though quite widely distributed in nature , its compounds chemically so resembled those of zirconium , its sister element , that it escaped detection until 1923 , when Coster and Hevesy announced the discovery of the element , to which they gave the name of " hafnium " , from Hafniae , the Latin name for Copenhagen , where their research work was performed . Hafnium has so far been found only as a minor constituent of zirconium minerals . Zirconium as an element was discovered more than 140 years ago , but only a few unimportant uses were found for the metal or its compounds until some 18 years ago ; it is still classed among the rarer commercial metals . It is not surprising , therefore , that hafnium has not yet found a definite place for itself in industry . Nevertheless it has commanded a considerable interest among scientists ; and in 1930 some 70 grams of perfectly pure oxide of hafnium were prepared in Europe . A commercial future for hafnium is already glimpsed in the radio industry , and its high melting point and electronic emissivity have already led to the taking out of patents for its use in radio tubes and incandescent electric lamp filaments and for the cathode surfaces of devices such as X- ray tubes and rectifiers .

Apr 1, 1931

By William J. Campbell

The columbite-tantalite mineral series was studied by various instrumental techniques to establish the relationship of density to composition. The samples used were carefully selected to obtain a mineralogical purity of at least 98 percent. Impurities were determined by optical microscopy, X-ray diffraction, and optical and X-ray spectroscopy. Each sample was analyzed by fluorescent X-ray spectroscopy for iron, manganese, columbium (niobium), and tantalum. The existence of a unique relationship in this isomorphous series permits a simple correlation of the intensity of a spectral line with the concentration of the analytical element.

Jan 1, 1955

By P. A. Bloom

Bureau of Mines research was conducted to develop effective separation methods that might be used in exploiting substantial tonnages of complex barite-fluorspar ores in Arizona. The exploitable reserves now may be increased as recent batch and continuous flotation tests demonstrated that a complex barite?-fluorspar ore from the Red Chief deposit, Yuma County, Ariz., could be selectively treated to concurrently produce (1) fluorspar and (2) a barite byproduct of marketable grade. The sample contained 24.8 percent CaF2 and 24.3 percent BaS04. Processing comprised production of a fluorspar product containing 97 percent CaF2 with an 82 percent recovery, using a sodium fluoride-lignin sulfonate-fatty acid reagent combination. Concurrent retreatment of the fluorspar tailing, using sodium cetyl sulfate as a collector, yielded a barite product of 94 percent BaS04 grade with a 71-percent recovery. The products met specifications for acid-grade fluorspar and drilling mud-type barite.

Jan 1, 1963

By T. E. Gray

This report describes the preparation characteristics of the most significant coal beds in Wise County, Va. It is one in a series of reports planned to determine coals suitable for the production of metallurgical coke, either as mined or after beneficiation. Wise County produced approximately 6,600,000 tons of coal in 1955, of which about 2,110,000 tons was cleaned mechanically. The Federal Geological Survey has estimated that 1,341 million tons of measured and indicated coal reserves remained in the county as of January 1, 1951.

Jan 1, 1958

By Paul Hatmaker

Pumice and pumicite are siliceous volcanic substances quite similar in chemical composition , but somewhat different in physical properties , manner of formation , and mode of occurrence . Production in the United States has increased from 23,271 tons valued at $ 94,943 in 1910 , to 56,843 tons valued at $336,099 in 1930. Both pumice and pumicite are included in these figures as it has been impractical to collect statistical data on the separate commodities .

Mar 1, 1932

By John Nagy, Austin R. Cooper, Murray Jacobson

Data obtained in the Bureau's study of dust explosions of 313 elemental metals , alloys , catalysts , and ores comprising 54 types of material are summarized . Information is given on ignition temperature , spark energy for ignition , minimum explosion concentration , explosion pressure , rate of pressure rise , and in some instances , the admixed inert dust and oxygen concentration in an atmosphere required to prevent ignition of dust dispersions . The effects of particle diameter on explosibility and pyrophoricity are also discussed .

Jan 1, 1964

By C. C. Furnas

In the course of an investigation3 of the flow of gases through beds of broken solids the author obtained a number of data .on the specific volume of beds of broken solids of variously mixed sizes. A mathematical theory of the limiting conditions has been developed and some generalizations have been made for intermediate cases. A more definite knowledge of the relation between space occupied and size composition would be valuable to all those who are handling large quantities of broken materials. Such knowledge might be advantageously applied to the operation of a coke oven. For example, the output of the oven depends in general upon the number of pounds of coal which can be put in the oven at charging. It is known that the capacity of one battery of ovens was increased several per cent by slightly increasing the proportion of fine material in the charge.

Jan 1, 1928

By Arnold O. Tanner

The domestic mining industry continued to be strengthened and revitalized in 1989. The healthy conditions and the industry comeback that began in 1987 continued to spread and became more established for many commodities. Relatively comfortable and stable commodity prices, still found predominantly in the metals sector, reinforced other operational factors in bringing vitality to the mining and mineral processing industries. New streamlined business practices, mine and plant modernizations, and the progressive use of new technologies successfully helped lower operating costs and increase efficiency during the past 5 to 7 years. An element common to these three factors of industry renewal and growth was the ever-increasing infusion of and growing dependence on constantly advancing computer technology applications. This trend of increasing computerization was occurring throughout the mining and mineral processing business while it similarly was in most facets of modern business and culture. Some commodities and companies still struggled to outlive sluggish prices and other unstable market conditions or to modernize their businesses, but increases in productivity and profits were more common. A trend toward increased mechanical excavation in nonsoil materials was beginning to surface as a substitute for standard cyclic mine development techniques, such as drill-and-blast and surface shovel-and-truck routines. More continuous mechanical excavation offered the potential for increased production, fewer people at the working face, better ground control, and generally improved safety. The main limitation was rock hardness. The construction industry had already recognized the benefits of tunnel-boring machines for long underground drives and mechanical planers for pavement removal. The Colorado School of Mines held a short course during the year entitled, "Mechanical Excavation Techniques in Mine Development and Production,'" which was at-tended by nearly 100 engineers from 12 countries. The consensus of attendees was that for the most efficient use of these machines and techniques, new mining plans needed to be developed beyond the simple adaptation of those excavators to existing mine plans.1

Jan 1, 1991

By Harry Perry, Mary S. Esfandiary

This is a revision of a directory of coal research organizations throughout the world that was first published in 1961 as Bureau of Mines Information Circular 8008. Because of the wide acceptance of the first edition , a revision which would supply up- to - date information on coal research and which would facilitate communication among organizations of similar interest seemed important . This compilation includes the names and activities of organizations of various types -government , university , private , and industry . The areas of investigation that each organization is engaged in are indicated in broad terms : Analysis and constitution , mining and geology , preparation , briquetting , combustion , high- and low-temperature carbonization , gasification , conversion to solid and liquid fuels , and health and safety . Publications issued by and describing the work of each organization are cited ; almost all of the organizations also publish results of their investigations in the technical press . Selected technical and trade publications that publish information on the science and technology of coal and are not published directly by any of the organizations listed are cited in the pages following the list of organizations in each country . Information that would improve coverage and accuracy of the next revision of the publication will be welcomed by the Bureau of Mines .

Jan 1, 1966

By Richard D. Miller

This publication contains routine analyses and related source data for 350 natural gas samples from 19 States collected during calendar year 1962 as part of a continuous survey of the United States for occurrences of helium in natural gas. This survey has been conducted by the Helium Activity of the Bureau of Mines since 1917. The analyses published herein were made by mass spectrometer and a special helium analysis apparatus. Four previous publications have been made to present the results of 5,648 gas analyses made by the Bureau of Mines, Helium Activity, prior to 1962. The first, Bulletin 486, 3/ contains analyses and data on 2,195 gas samples collected during the period 1917-47. Bulletin 576, 4/ the second publication, includes data and analyses for 1,575 samples collected from 1947 through May 1956. The third bulletin 5/ contains 1,444 analyses and source data of samples obtained from May 1956 to January 1, 1961.

Jan 1, 1964

By Warren D. Longwill

The Bureau of Mines inventoried Federal lands in the State of Oregon and classified them in detail, section by section, according to their availability for mineral exploration and development as affected by legal status and agency management practices. The Bureau determined areas of the State having past mineral production and/or known metallic mineral resources and areas favorable for coal, oil, gas, and geothermal resources, and prepared maps that spatially compare the availability of Federal mineral land with these mineral areas to demonstrate the extent of restrictions to mineral entry. Oregon contains 62.1 million acres, of which 33.9 million acres or 55% is Federal mineral land. About 2.3 million acres of Federal land is favorable for selected metallic mineral deposits, of which 64% is available, 13% is restricted, and 23% is unavailable. Of the 21.1 million acres of Federal leasable land favorable for oil and gas, 68% is available, 11 % is restricted, and 21 % is unavailable. Of the 146,720 acres favorable for coal, approximately 71% is available, 13% is restricted, and 16% is unavailable. Federal leasable land favorable for geothermal resources amounts to 458,968 acres, of which 42% is available, 34% is restricted, and 24% is unavailable.

Jan 1, 1988

By G. L. Oldright

[This paper is the fifth 4/ of a series of publications on smelting in the load blast furnace. The objects of this investigation are to determine the conditions obtaining within the blast furnace by direct experimentation, and to correlate the behavior of the furnace at various tines with the main factors governing the operation of the blast furnace, and metallurgical losses.]

Jan 1, 1929

By David A. Monaghan, Kenneth R. Maser, Adi R. Gurdar, D. Randolph Berry

5. Development of Initial Probing System 5. 1 Introduction The preliminary evaluation of a variety of potential methods for initial probing showed that the optical system using closed circuit television (CCTV) and the sonar, or acoustic ranging, system were the most promising. The former is capable of pro¬viding a visual display of the mine passages in a clear, non-smoky environment, and the latter is capable of providing a map of the spatial location of the coal surfaces making up the entries, as well as objects, such as cribs, mining machines, etc., in the passages in both smoky and non-smoky environments. The sonar system used in conjunction with the CCTV in a clear environment can greatly assist in resolving the spatial distribution of objects seen on the TV screen. Further, in a smoky environment the interpretation of the sonar information could be facilitated if some visual information were also available. CCTV systems exist but require some modifications to suit this particular application. The Industrial Hazards and Communications Division of the Bureau has an ongoing program for the development of such a CCTV system. Rather than duplicate this effort in developing a CCTV system, it was decided to evaluate the possibility of utilizing their system for initial probing, while continuing with the develop¬ment of a system which would work in any environment, including the presence of dense smoke. The concept of using sonar for the initial probing of mine passages represents the application of new technology requiring development. The results of such a development effort undertaken during the course of this program are described in the following sections.

Jan 1, 1973

By F. R. Cattoir

Analytical methods are presented in this paper for determining soluble titanium, total titanium, indicated titanium, and average effective valence in titanium chloride - sodium chloride mixtures. In addition, data are given showing the effects of coarse and fine grinding on the degree of oxidation and average effective valence of such samples. INTRODUCTION The Electrometallurgical Experiment Station at Boulder City, Nev., as part of the Bureau of Mines program to obtain more efficient utilization of our natural resources, has been developing and improving titanium extractive metallurgical methods and techniques since 1945. Numerous reports have been published describing development of the Kroll process,4/ the electrorefining technique,5/ and methods of analyzing titanium sponge.6/

Jan 1, 1957

By Frank E. Federspiel

In 1992, the Bureau of Mines conducted a mineral resource investigation of the 78,000-acre Garns Mountain study area in southeastern Idaho. The area had been proposed for Wilderness. It is underlain by Paleozoic to Mesozoic-age sedimentary rocks about 11,000 feet thick. Rocks have been faulted, offset, and folded as part of the northerly-trending Idaho-Wyoming Overthrust Belt. Study area mineral occurrences are: phosphate in the Permian Phosphoria Formation; coal in the Cretaceous Frontier end Bear River Formations; and uranium in carbonaceous and phosphate-bearing shales and coal of these formations. Four zones of phosphate are estimated to contain about 528 mitt ion tons of rock with over 10% P205; samples of phosphate-rich rock also contained as much as 3950 ppm chromium, 3280 ppm vanadium, 23 ppm gallium, and 5540 ppm zinc. Fragments of poor-quality coal and carbonaceous shale were found in the area; coal was mined near the northeast border. Uranium content up to 0.016% U3O8 is in carbon-rich shales. Oil and gas were drilled for, with minimal success, in folded sedimentary rocks (frontier and Nugget Sandstone) in the Horseshoe anticline, near the east border. Examined workings included 12 dozer cuts, 4 trenches, 2 prospect pits, and 2 caved adits. No production is known, and no leases or claims are held for the area.

Jan 1, 1992

By William J. Campbell

One of the principal objectives of the Bureau of Mines program for developing super refractory materials is to obtain fundamental data on the physical properties of refractory oxides. This particular investigation obtained accurate thermal expansion coefficients for alpha alumina and evaluated, critically, those coefficients with other published values. High-temperature X-ray diffractometer measurements, by the Bureau, showed that alpha alumina expands anisotropically with expansion parallel to the c axis approximately 10 percent greater than parallel to the a axis. Thermal expansion characteristics of four different alumina samples were determined up to 1,200° C.; the results are presented in both tabular and graphical form. The combined random and systematic errors in the measurements are considered less than 3 percent above 500° C, and approximately 2 percent at 1,000° C. No differences in expansion were observed between the samples or between the heating or cooling cycles.

Jan 1, 1961

By V. E. Edlund

Laboratory batch flotation tests were conducted on copper converter slags to evaluate the relative merits of recovering copper from slow-cooled versus water-quenched slags. Three slags containing 1.6, 5.0, and 6.6 percent copper were used. More than 90 percent of the copper was recovered in a rougher concentrate leaving a 0.2- to 0.3-percent copper tailings when treating slow-cooled slag. Lower recoveries and higher copper tailings ranging from 0,5 to 0.6 percent copper were obtained from quenched slag. Grindability studies were made on the respective heat-treated slags. Quenched slags proved more difficult to grind than slow-cooled slags. Cost studies showed that (1) the cost of slow cooling and crushing off-sets any advantages of higher copper recoveries from slow-cooled slag, and (2) water-quenched slag, which requires no crushing preparatory to grinding, could be treated more economically. Costs based on processing 1,000 tons of slag per day would be $1.85 per ton for quenched slag versus $2.37 per ton for slow-cooled slag.

Jan 1, 1971

By F. R. Cattoir

The Federal Bureau of Mines refined chromium from an aqueous electrolytic process in molten sodium chloride-chromium chloride electrolytes. Oxygen and nitrogen contents were reduced by a factor of 10 to 40, but most other impurities were little changed. The product usually contained a little more iron than the feed. Since iron was entering the bath from the iron pot and the graphite liner at a nearly constant rate, contamination of the chromium deposits by it was more serious at low currents and deposition rates. A few runs in an iron cell with a nickel liner yielded chromium containing one half as much iron as the feed, but up to 1.5 pct. nickel. In all cases the anode feed lay in the bottom of the container, which itself was used as the anode connection. With a 12-in. cell, variations in applied voltage from 0.05 to 1.5, in current from less than 10 to over 100 a., and in initial cathode current densities from less than 100 to over 2,000 a./sq.ft. had little or no effect upon the analysis of the metal produced) except for iron content. Changes in bath analysis from 3 to 11 pct. chromium were also without effect. These changes did bring about large differences in the physical forms of the crystals obtained. The thick heavy crystals produced at low voltage and current contained voids which made them difficult to leach free of chlorides. Easiest to leach were the thin leaf-like crystals obtained at around 1 v.

Jan 1, 1960