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By Albert W. Deurbrouck

This report describes the preparation characteristics of the significant coalbeds in Russell County , Va . Almost 2 million tons of coal was mined in 1961 ; 75 percent of the coal was cleaned mechanically in preparation plants in the county . The coal of Russell County is ranked as medium- to high- volatile bituminous , contains small amounts of sulfur , and generally requires some cleaning to reduce the ash content to limits acceptable for metallurgical purposes .

Jan 1, 1963

By A. W. Deurbrouck

This report describes the preparation characteristics of the significant coalbeds from which samples could be obtained in Webster County, W. Va. In 1964, approximately 825,000 tons of coal was produced in the county, of which 732,000 tons was mechanically cleaned in three preparation plants. The Sewell coal bed accounted for 94 percent of the coal produced. Twelve samples were collected from five coalbeds. Four of the samples would require upgrading to meet metallurgical requirements; two others of just over 8.0 percent ash would require some upgrading. In general the coalbed samples collected in the county were of medium-sulfur and medium-to low-ash content as received or after removal of the sink 1.58-specific-gravity material.

Jan 1, 1966

By C. P. Fang, V. A. Marple, K. L. Rubow

"Studies of the flow fields and particle impaction characteristics are more complicated in multi-nozzle impactors than in single-nozzle impactors, since the jets of air must penetrate cross-flowing air to impinge on the impaction plate. Results of heat and mass transfer analysis are employed to describe the cross-flow pattern in multi-nozzle impactors. A cross-flow parameter has been derived to predict the deflection of the air jet by the cross-flow. This parameter is expressed as a function of the geometric parameters for the multi-nozzle impactor. DnN 4D,, where N is the number of nozzles, Dn the nozzle diameter and D, the nozzle cluster diameter. Empirical particle collection data show that multi-nozzle impactors operate satisfactorily, if the cross-flow parameter is less than a critical value of 1.2. Impactors operating with a cross-flow parameter larger than this critical value are shown to possess poor particle collection characteristics.Inertial impactors of many designs have been used for sampling aerosol particles. Impactors can be single stage, consisting of a nozzle and an impaction plate, or a cascade impactor with several stages in series. The simplest design for a stage is a single nozzle with a flat impaction plate. However, many designs use stages with multiple nozzles of identical size, which allows for compact impactors to be designed at rather substantial flow rates and moderate pressure drops.Nearly all of the theoretical work, and much of the experimental work, has been performed on single-nozzle impactors. The results of single-nozzle impactor analysis are often applied to multiple-nozzle impactors, which are assumed to be a group of individual nozzles, each operating as though they were single nozzles. However, an important fact is often ignored: the interaction of flow from adjacent nozzles can change not only the fluid mechanics in the impaction region, but also the locations of the jet stagnation points, and the impaction characteristics of each nozzle.The effect of multiple nozzles on the particle collection characteristics of impactors has been studied by a few investigators. May (1964), Fletch et al. (1967), Friedrichs (1968), and Vaughan (1986) reported that the quantity of particles in deposits of nozzles in the first two stages of the Andersen multi-nozzle cascade impactor were not equal. The inner deposits appeared to contain fewer particles than the outer ones. However, Vaughan (1986) in addition showed that many of the deposits in the outer three rows were missing on the first stage, even though the outer deposits that were present were larger than the inner deposits.May (1964) conducted experiments and explained the phenomenon of smaller deposits near the center than near the edge. He noted that in Andersen cascade impactors the air issuing from the nozzles moves radially outward along the narrow channel between the nozzle plate and the impaction plate. This flow at 28.31min -1 created a pressure difference of about 1 mm water between the inner and outer sections of the channel. The effect was most pronounced in the first two stages, where the pressure drop across the nozzles was also about 1 mm water. Here, the flow velocities in the nozzles, and hence the deposits, were smallest at the center and increased toward the periphery of the impaction plate. since the pressure drop across the nozzles was the smallest at the center and a maximum at the periphery. This effect was negligible in the lower stages because of a larger pressure drop across the nozzles. According to May (1964), this effect could be eliminated by increasing the nozzle-to-impaction-plate distance to three nozzle diameters and improving the nozzle arrangement to allow air flow to escape to the periphery more easily."

Mar 1, 1992

By E. L. Garton

The Bureau of Mines for a number of years has been conducting an investigation of crude petroleum from producing fields in the United States and the Western Hemisphere and has published a series of reports on these fields. Analyses of crude-oil samples from many oil fields of Oklahoma are given in Bulletin 2913. Analyses of 21 representative crude oils from various producing zones of the Oklahoma City field are given in this report. A close study of the analyses reveals very few differences in the general characteristics and chemical properties of these oils.

Jan 1, 1932

By R. S. Warfield

Following World War II, the rapid increase in both military and civilian activity in the area served by the Alaska Railroad stimulated interest in the availability of local sources of nonmetallic minerals that might be used for building materials. Except for abundant sand and gravel and some pumice, the construction industry of the area depended entirely on high-cost imports for building materials of mineral origin. Because continued rapid growth was anticipated, development and use of local sources of such materials was advocated by both military and civil authorities to reduce the high costs of con¬struction and bolster the unstable economy of the area. The U.S. Department of the Interior began a program On included examining the numerous deposits of nonmetallic minerals accessible to the Alaska Railroad to determine their possible use as raw materials for the construction industry. Preliminary field investigations were made by the Geological Survey. The more promising deposits were subsequently examined and sampled by Bureau of Mines engineers, and the samples were subjected to the laboratory tests necessary to indicate the chemical and physical characteristics of the raw materials or their products. Such field and laboratory investigations were conducted on clay, shale, argillite, limestone, gypsum, and pumice taken from various parts of the area. In initial phasees of the work, done irate 1948 through 1952, many of the deposits examined were suitable for proctoring building materials. Results of the work completed during that period have been published in a Bureau of Mines report3 giving general information and detailed data on more than 35 deposits that were investigated.

Jan 1, 1962

By Thomas Fraser, William L. Crentz

"INTRODUCTION Sulfur is a most damaging impurity in many of our American coals. From the older coal industry of Europe and Britain we can apparently learn but little about the problem of preparing and using high-sulfur coal. Although washing has long been established there for controlling ash content, sulfur is referred to rarely, as the important deposits are singularly low in sulfur.On the other hand, widely distributed coal deposits of America differ tremendously in sulfur content. Many of the more extensive beds contain too much sulfur for metallurgical use, and almost everywhere except in the Rocky Mountain and Pacific coast regions sulfur control is at least a potential problem. American coal-preparation engineers are confronted not only with great variations in the total quantity of sulfur in coal but with an intricately varying pattern of the physical and chemical forms in which the sulfur occurs. It must be conceded that the baffling problem of sulfur reduction in coal is as yet substantially unsolved, for there are but few isolated instances in which we have been able to prepare a satisfactory metallurgical fuel from coals containing as much as 2.0 percent sulfur in the raw state.It has been assumed generally that organic sulfur, being chemically combined with carbonaceous matter, is distributed throughout the coal matter and that it remains unchanged in the clean-coal part of the product during washing.Sulfur that may be washed out of the coal is that part that is combined with the iron in pyrite lenticles associated with the coal. In most of our coals it has been found that, besides the visible bands, lenses, and flakes of pyrite, extremely small and even microscopic particles of pyrite 4/ are distributed through the coal matter. Only the free, relatively coarse pyrite particles .are removed by conventional coal-washing devices, and usually most of the sulfur is still left in the product."

Dec 1, 1947

By L. C. Brichta

The Melrose zinc-lead. deposit is in an area of structural disturbance of sedimentary rocks in the Melrose mining district in Cherokee County, Kans., 25 miles west of Joplin, Mo., adjacent to the northwest limits of the Tri-State district. Mining and milling in the Melrose district has been sporadic and. very limited, largely due to the high cost of exploration through great thicknesses of barren rock, 350 to 440 feet overlying the ore deposits. No mining has ever been done on the Melrose zinc-lead tract, but it has been drilled extensively. The drill-hole logy indicate extensive structural deformation, silicification, and zinc-lead deposits in the Boone limestone-chert formations of the Mississippian series, which is overlain by thick-bedded Pennsylvanian shale and sandstone. Analyses of samples from Bureau of Mines drilling indicate the ore minerals are sphalerite and galena with no evident oxidation. During the period from November 2, 1949, to March 13, 1950, the Bureau of Mines investigated the deposit by churn drilling and sampling 23 holes aggregating 10,405 feet of bore. Factual data on the investigation and logs of holes drilled by private parties and the Bureau of Mines are presented in this report.

Jan 1, 1951

By Thomas R. Bur

This method of performing general transformations by use of Eulerian angles greatly reduces the time required for the determination of values for the elastic compliance constants (sij), elastic stiffness constants (cij ), Young's modulus, shear modulus, or Poisson's ratio for any orientation the cartesian coordinate system in an anisotropic material.

Jan 1, 1969

By R. V. Ramani, C. B. Manula, A. Owili-Eger

PART 1 THE INPUT AND OUTPUT DATA AND THE MINE SCHEMATIC SHOWING THE FLOWS FROM COMPUTER SOLUTIONS FOR APPLICATION I

Jan 1, 1975

By Kathleen M. PH. D. Kowalski

This paper discusses human judgment and decision-making under stress. The authors review selected recent literature across various disciplines and suggest a definition of stress within the context of decision-making during the management of emergencies. They also discuss fieldwork by the Pittsburgh Research Laboratory, NIOSH, which explores traumatic incident stress, the relationship between previous training and performance under stressful conditions, and human behavior in underground mine fires. The authors assert that stress is one of the factors that decision-makers must contend with in most life-or-death situations. They suggest that a better understanding of individual's judgment and decision-making activities while under stress would yield a better understanding of how people reach the choices they make in emergencies. This enhanced understanding would be of enormous value to emergency managers, researchers, and policymakers.

Jan 1, 2008

By Albert W. Deurbrouck

This report describes preparation characteristics of significant coalbeds in Tazewell County , Va . In 1961 Tazewell County produced 933,110 tons of clean coal from six coalbeds ; the Lower Banner , Raven , Jawbone , Upper Seaboard , and Pocahontas No. 3 and No. 5. Samples from all of these beds , except the Lower Banner , were included in this study plus a sample from the Pocahontas No. 4 bed . Of the samples collected , only one would require upgrading to be of metallurgical quality . The coals ranged in rank from high- volatile -A to low- volatile bituminous .

Jan 1, 1963

By Albert W. Deurbrouck

Twelve samples from six Barbour County coal beds were analyzed for this report. The samples collected were generally high sulfur content coals, frequently exceeding 3 percent in the raw-coal sample. Many of them could not be upgraded to acceptable metallurgical standards even by rigorous preparation procedures. The production of coal in the county in 1963 amounted to almost 3 million tons of which 44 percent was mechanically cleaned.

Jan 1, 1965

By Lloyd Williams

A vertical air shaft in the Birmingham, Ala., iron district was sunk with a circular cross section and lined with concrete at a relatively low cost to provide needed ventilation for an iron-ore mine. The method of sinking the shaft is described, and the costs are stated in mar-hours with a descriptive list of equipment and a statement on the size and use of temporary buildings. Preparation began May 2, 1955, and the shaft was completed at a depth of [680] feet by September 22, 1956. By October 1956, all temporary building and [aft]-sinking equipment had been removed. The total direct-labor cost for the operation, including preparation and dismantling, was 50,700 man-hours, or 30.2 man-hours per foot. Total rock and dirt removed amounted to 17,523 cubic yards (in place), and the shaft lining required 4,635 cubic yards of concrete to form a circular air shaft with an inside diameter of 16 feet.

Jan 1, 1960

By E. C. Lane

This paper on the physical and chemical properties of crude oils from California fields is one of a series of reports on the oil-producing districts of the United States. The paper includes a short discussion of results, tabular data, and individual analyses of 16 California crude oils. Analyses of other oil from California have been published in Reports of Investigations 25954/, 26085/, 28466/, and 30747/. The samples were obtained by members of the San Francisco office of the Bureau of Mines. The collecting of the samples vas facilitated by the courtesy of representatives of oil companies in California.

Jan 1, 1937

By E. C. Lane

This paper on the physical and chemical properties of crude oils from California fields is one of a series of reports on the oil-producing districts of the United States. The paper includes a short discussion of results, tabular data, and individual analyses of 16 California crude oils. Analyses of other oil from California have been published in Reports of Investigations 25954/, 26085/ 28466/, and 30747/. The samples were obtained by members of the San Francisco office of the Bureau of Mines. The collecting of the samples vas facilitated by the courtesy of representatives of oil companies in California.

Jan 1, 1937

By Sabri Ergun, Robert W. Smith, Victor H. Tiensuu

Factual geometries are considered for X- ray scattering studies of weakly absorbing materials by both reflection and transmission methods . These studies are usually made on slab specimens to obtain adequate scattered intensities ; however , the intensities are appreciably influenced by absorption of the X-rays in passing through the specimens . Conventional equations derived to account for this absorption are based on idealized geometries , but for polycrystalline carbons the use of idealized geometries leads to several percent error in the corrections to be made . Use of factual geometries substantially reduces this error .

Jan 1, 1964

By G. A. Crowder

Far infrared spectra, most of them in the region 15-200 microns and for both the liquid or solution state and for the vapor state, were obtained for twenty-seven compounds.

Jan 1, 1965

By F. E. Cash

The Holmes Safety Association , organized and named in honor of the late Dr. Joseph A. Holmes , first director of the United States Bureau of Mines , has for its object the prevention cf accidents , the improvement of health conditions at work, in the home , and in public places , and the promotion of the general welfare of its members . As a means of preventing accidents and advancing health and safety , the Holmes Safety Association disseminates information , gives instructions on subjects related to safety , and promotes first -aid and other forms of protective and accident - prevention training . This organization is intended to work and cooperate in the closest possible way with existing mine or plant safety organizations in conducting educational , social , and recreational activities for the promotion of health , safety , and efficiency .

Jan 1, 1929

By R. Hogg, T. F. Dumm

"There is a considerable need for standardized respirable dusts with consistent, reproducible characteristics which simulate those of actual mine dust. The availability of such materials should be a significant factor in promoting coordinated research into dust characterization and mine monitoring, dust control, and the biomedical aspects of dust toxicology. The use of an opposed-jet, fluid-energy grinding system in closed circuit with a cross-flow, centrifugal air classifier for preparing bulk quantities of respirable-size dust has been investigated, and appropriate, standardized procedures have been established. By stage-crushing, screening, and fine-grinding with a Donaldson Acucut classifier/mini-grinder system, it is possible to produce bulk quantities of respirable dust at relatively high rates. Using minor modifications to the system, broader or narrower size distributions can be prepared within the respirable range. The system has been shown to reach steady-state with respect to product size distribution very rapidly. However, preferential grinding/classification effects appear to lead to a slow build-up of mineral matter in the circulating load with a corresponding slow change in product composition with time. In those applications where the dust composition is required to match that of the feed coal, it may be necessary to allow considerable time for a true steady-state to be established.Standard respirable dust samples have been prepared from coals representing the western (high volitile A bituminous), central (medium volatile bituminous) and eastern (anthracite) mining areas of Pennsylvania. Quartz and kaolin clay samples, representing important mineral constituents of coal dust have also been prepared. Extensive characterization studies have been performed on the samples to evaluate chemical and mineralogical composition and the distributions of particle size and specific gravity. Detailed information on the original coals is available from the Penn State Coal Data Base. The standard coal dust samples appear to simulate actual mine dust very well with respect to particle size and shape, but generally have somewhat lower ash content. Samples of these standard dusts have been made available to research groups concerned with respirable dust in mines."

Mar 1, 1989

By E. S. Shedd

The Bureau of Mines investigated electrowinning and tapping lanthanum metal from lanthanum oxide in a fluoride bath. The electrolyte was composed of LaF3, BaF2, and LiF. Metal containing 0.2 percent impurities was produced at a rate of over 2 pounds per hour. Principal impurities were carbon, aluminum, and silicon. Low-carbon metal was produced by continually discharging the carbon oxide gases and maintaining 0.1-atmosphere pressure. Anode reactions and cell design were found to be important factors in cell operation. Both frozen electrolyte skulls and tungsten metal crucibles proved satisfactory for collecting the metal and did not react with the molten lanthanum.

Jan 1, 1966