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By J. G. Kirby

The total number of petroleum refineries in the United States decreased during 1951, while the total crude-oil charging capacity continued to increase. There were 350 refineries as of January 1, 1952, compared with 357 a year earlier, according to the annual Bureau of Mines capacity survey. A gain of 369,241 barrels in daily refinery crude through-put capacity during 1951 brings the total to 7,332,885 barrels daily. The capacity of the average refinery to process crude-oil was 20,951 barrels daily, an increase of 1,445 barrels daily over the previous year. Capacity added in the Texas Gulf district accounted for 36 percent of the total increase; the Indiana-Illinois-Kentucky district, 23 percent; the East Coast district, 19 percent; the Oklahoma-Kansas district, 12 percent; and the Texas Inland district, 11 percent. The California district was the only one reporting a decline in crude-oil refining capacity, the total being 14,200 barrels daily below the previous year. Reported as under construction January 1, 1952, was an additional crude-oil capacity of 282,680 barrels daily, an increase of 77 percent over the January 1, 1951, total of 160,100 barrels. The capacity now building is for the expansion of existing facilities, since no new plants had been begun as of the first of the year. Three or four companies have plans to build refineries in the Williston Basin area of North Dakota, but no definite locations or dates when construction will begin have been announced.

Jan 1, 1952

By K. K. Kelley, W. W. Weller

Heat capacity measurements of lead molybdate and lead tungstate were conducted over the temperature range from 51 ° to 298 ° K. The entropies were found to be S298.15 = 39.7 ± 0.5 cal / deg mole for lead molybdate and S298.15 = 40.2 ± 0.5 cal / deg mole for lead tungstate . The entropy values were combined with other pertinent data to obtain the entropies of formation of the two compounds from their constituent elements and oxides .

Jan 1, 1964

By Robert H. Ridgway

This circular outlines salient facts regarding the manganese-ore industry in the United States and the world. It is founded chiefly upon published information available in the literature of the subject. The Bureau of Mines has in its files additional, more detailed data upon many of the topics presented very briefly here, and will endeavor to assist the mineral industries and public by giving further information in response to individual inquiries. The Bureau will welcome comments, criticisms, and contributions of data that may assist in making later additions of this circular more accurate, or in developing more fully its mineral files pertaining to manganese. In reporting the production of manganese-bearing ores in the United States the following classification has been adopted by the Bureau of Mines: (1) Metallurgical-grade ores, under which have been classified manganese ores containing 35 percent or more of manganese used in the manufacture of iron and steel, ferruginous manganese ore containing 10 to 35 percent of manganese, manganiferous iron ore containing 5 to 10 percent of manganese, and manganiferous zinc residuum; (2) battery ore; (3) fluxing ores, under which are classified ores that may contain a few ounces of silver and are rich enough in manganese to make them valuable chiefly for fluxing purposes in nonferrous smelters; and (4) miscellaneous ores, under which are classified the ores shipped to brick manufacturers, glass makers, and manufacturers of manganese chemicals.

Jan 1, 1933

By Kenneth P. V. Lei

The Bureau of Mines investigated a silver-catalyzed oxidative procedure for leaching an arsenical copper sulfide concentrate containing 10 pct As and 32 pct Cu_ Currently, there are no environmentally safe means to treat arsenical copper concentrates in the United States. Leaching was conducted in a 2-L autoclave reactor. The effects of catalyst concentration, O2 pressure, temperature, and H2S04, Cu, As, and Fe concentrations in the leaching solution on extractions of metals from the concentrate were determined. The best leaching conditions for extracting 95 pet eu and As and less than 21 pct Fe were 260 g/L concentrate, 0.007 mol/L (1.0 g/L) AgCI, 3.0 mol/L (294 gIL) H2S04, 1000 C, 60 psig 02, and 6 h. Copper as CuS04-5H20 was recovered by crystallization from the pregnant solution. Arsenic, as AS203, was recovered from the copper mother liquor by solvent extraction, with tributyl phosphate, S02 reduction of As5+ to As3+ in the strip solution, and crystallization of the As3+. The silver catalyst was recovered by contacting the leached residue with a brine solution. A conceptual scheme is proposed for treating arsenical copper sulfide concentrates.

Jan 1, 1987

By Thomas A. Phillips

This publication is an economic evaluation of the Bureau of Mines electrolytic process for recovering lead from scrap lead-acid batteries. In this process, scrap batteries are crushed and separated into metal and sludge fractions. The metal fraction is cast as anodes and electro- refined. Lead in the sludge fraction is converted to lead carbonate by reaction with an ammonium carbonate-ammonium bisulfite solution. The lead carbonate is then dissolved in a fluosilicic acid electrolyte from which pure lead metal is electrowon. A cost estimate is presented for a plant capable of processing 10,000 scrap batteries per day. The fixed capital cost for this plant is estimated to he $14 million on a fourth quarter 1984 basis. Operating costs are estimated to be $0.15/lb Pb recovered. Assuming a lead selling price of $0.17/lb, the interest rate of return on investment after taxes is 11 pct. A lead selling price of about $0.21/lb is needed to obtain a 20-pct-interest rate of return.

Jan 1, 1986

By Irving Hartmann

The fire end explosion hazard of excessive coal-dust deposits in mines has been recognized for many years, and important measures have been developed for reducing dust formation and to alley loose dust near its source. Nevertheless, in the course of normal mining it has been estimated that 1 to 3 percent (in some thin, friable seams up to 10 percent) of the total coal mined is reduced to dust of through-20-mesh fineness. In highly mechanized, continuous mining operations the production of fines is even greater. Most dust is trapped near its point of origin and removed from the mine, but large quantities are transported by the air current and by haulage into entries, where the greatest proportion settles on the floor and the balance on the rib and roof surfaces. The latter is generally finer in particle size than the floor dust; this, coupled with its more advantageous position for dispersion, makes the rib-roof dust (also to be referred to as overhead dust) a greater potential explosion hazard.

Jan 1, 1954

By B. Olson, V. A. Marple, D. J. Radet

"Gravitational forces have been found to be an important factor in defining the particle collection efficiency curve of inertial impactors for large particles. In general it was found that if the parameter G = gW /V 0 2 (g is the gravitational acceleration. w is the nozzle diameter and V 0 is the average fluid velocity at the nozzle throat) in greater than 10-3 the efficiency curve would shift to lower panicle sizes. No effect could be seen for lower values of G.IN'IRODUCTIONInertial impactors have long been used as classifiers for airborne particles. By proper design of the nozzles and flow rate it is possible to classify particles with a fairly sharp cut in the particle size range from approximately .02 µm to 50 µm. Because of inertial impactors wide usage they have been extensively studied calibrated and evaluated. Most of these studies have been experimental calibrations of single stages using monodisperse aerosol particles. However, due to impactor simplicity. i.e. a jet of particle laden air impinging upon a flat plate with large inertia particles crossing the streamlines and impacting upon the plate the impactor also lends itself to theoretical evaluation.The most comprehensive method for analyzing impactors theoretically is to use finite difference solutions to the Navier-Stokcs equations and solve for the velocity components and pressure at node points of a grid placed over the area of interest. Using iteration and relaxation techniques the value of the velocity vectors can be determined at these node points with good accuracy. Once the velocities arc known, theoretical particles of known size can be placed into the now field and their trajectories determined by analyzing their equation of motion using numerical methods.Rader and Marple (1985) have performed theoretical analysis on impactors and have included such factors as Ultra-Stoksian .drag and the physical diameter of the particle in their analysis. However, even with these· factors included, there appears to be discrepancy · between the experimental and theoretical results when the particle size is larger than approximately 4 or 5 µm. One possible reason for this discrepancy could be the effect of gravity on the particle as it passes through the impactor. Therefore, a program was initiated to study the effects of gravitational forces on the collection· efficiency of particles in impactors. The results of that study arc presented here."

Jan 1, 1990

By James J. Hanslovan

Stresses that damage coal mine trailing cables were investigated to obtain a quantified description of cable-stress locations, magnitudes, and frequency of occurrence. Stresses occurring in operating mining sections were measured and observed. Answers to questions that arose during the underground investigations were pursued under controlled conditions, both in the field and in the laboratory. Cable-handling suggestions that minimize or eliminate the stresses are summarized in the form of recommendations to mine operators.

Jan 1, 1979

By Donald J. Barnes

The Glacier View RARE Ii further planning area contains no identified mineral deposits, other than stone, which cannot compete favorably with similar deposits closer to major markets. Pierce County mining claim records show six coal claims were located in the study area between 190b and 1907; however, no coal was found at the described locations. Two coal prospects, the H.O. Lamming and Floyd Rice, are within 0.5 mi (0.8 km) of the area's west boundary (fig. 1). At these prospects, impure bituminous coal beds strike approximately north and dip east toward the study area. Analyses of samples 1/ indicated an average heating value of 2,767 BTU 2/ per pound (6,436 joules per kg). Because of the low heat value, this coal is subeconomic. Intense folding and faulting which disrupted the beds would limit the use of conventional coal mining equipment, making future economic development even less likely. Trinity Resources of Houston, Texas has leased approximately 1,404 acres (568 ha) inside the study area and an additional 1,020 acres (413 ha) adjacent to the study area for oil and gas exploration. However, no oil or gas wells are known to have been drilled in or around the study area.

Jan 1, 1983

By Verne E. Hooker

In situ stresses, based on isotropic and anisotropic relations, were evaluated using computer techniques from overcoring data obtained in dimension stone quarries along the Appalachian Piedmont, the Ozark Uplift, and the Ouachita Tectonic Belt. Stresses in the horizontal plane near the surface are compressive and range from 100 to 4,500 psi. The direction of maximum compressive stress seems to be alined with the general tectonic structure for most of the determinations. The ratio of the maximum to minimum elastic parameters in the horizontal plane ranges from 1.05 to 2.46 for these competent rocks. Isotropic versus anisotropic stress determinations show differences only as great as 25 percent in stress magnitude and 25° in orientation.

Jan 1, 1969

By R. R. Nothdurft

The internal friction of eight single crystals of magnesium with orienta-tion ranging from 10° to 84° was measured at 33.5 kc and 272° C, and the results were interpreted in terms of the pinned-dislocation model proposed by Granato and Lucke. Results show that the strain-amplitude-dependent decrement varies with orientation in a manner predictable by the G-L model. Different values of strain-amplitude-independent decrement were observed at different orientation angles, but correlation with the theory was not conclusive. Problems and steps for further study are discussed.

Jan 1, 1965

By R. D. Currie

"INTRODUCTION Compressed air for operating coal-mining equipment is seldom considered in conjunction with modern methods and appliances. But the Jamison Coal & Coke Co. has proved the economy and efficacy of compressed air for this purpose at its Mine 8 near Farmington, 8 miles west of Fairmont, Marion County, W.. Va., and the mining industry as a whole concedes its superior safety in gassy or dusty coal mines.The uses for compressed air in coal mining are now generally associated with such equipment as coal punchers, chain-breast machines, and to a lesser extent the ""radialaxe"" type of mining machines.Electricity has rapidly superseded compressed air for power in coal mines during the past 20 years; and in the last few years the general, and often unwise, use of electricity at the face region has taken on added impetus through the widespread use of mechanical loading equipment.Some of the unfavorable results of this increased use of electricity are shown in the growing number of mine explosions and fires of electrical origin. In the past four years 59 explosions of this type took the lives of 672 men, or 74.8 per cent of the total number of deaths from explosions were due to explosions of electrical origin.3In 1926, an explosion in Mine 8 of the Jamison Co. killed 19 men. The exact source of ignition was not determined, although it was definitely decided that it was of electrical origin and probably was at an electric coal-cutting machine.Prior to this disaster the company had done some experimenting with compressed-air-driven mining machines, and its Mine 9 had been completely equipped with air-driven chain-breast machines; a few of these machines were also in use in Mine 8. The explosion, however, gave impetus to the adoption by this company of compressed air for operating face equipment. The chain-breast machines were as satisfactory as electric machines of the same type; but the trend in the industry was toward faster cutting machines, which required less physical exertion on the part of the operating crews. A track-mounted machine of the arcwall type was found to be suitable for the conditions and system of mining, so that one of these operated by compressed air was developed by the Jeffrey Manufacturing Co. working with the officials of the Jamison Co.The first of these machines was installed in the latter part of 1926 and additional machines were delivered from time to time, until at present there are nine of them in the mine. Necessary improvements have been made, with the result that a fast-cutting, easily handled, efficient, and safe mining machine has been developed for cutting the hard Pitts¬burgh bed coal of the Fairmont field."

Oct 1, 1932

By N. E. Hanna

[Testing explosives for safe use in coal miner ran boon an important factor in preventing mine explosions. In the United States, explosives that have been approved by the Bureau of Mines are called permissible explosives. A purvey of the history of coal mining since permissibility testing welt, instituted some 4 years ago shown that there is no record of a coal-mime explosion caused by permissible explosives when used in a manner prescribed by the Bureau. To maintain the appropriate standards of quality, the Bureau of Mines conducts a series of examinations and tenth on samples of explosives collected in the field. In what is considered the most crucial test, teat 1, the explosives An fired from a steel cannon into a gallery atmosphere containing a mixture of natural gas and air, In another important test, test 4, the explosives charge to fired into a mixture of natural gas, air, and coal diet. To satisfy the permissibility requirements, the explosive must undergo throe gallery teats without igniting gas or coal duet. Other tests also are required for permissibility, but they do not come within the scope of the present paper, which studies the factors affecting the incendivity of explosives when fired into methane, air, and/or coal-dust mixtures. It in believed that a better understanding of the factors will contribute to the development of safer explosives.]

Jan 1, 1954

By A. L. Engel

This report is a compilation of results of preliminary concentration tests of nine manganese-ore samples in 1953-1954. Three samples were from Nevada and the other six from California. These samples represent marginal or low-grade ores from deposits that have been mined selectively in the past. The present interest lies chiefly in the possibilities of concentration of the remaining low-grade ores for economical exploitation. The treatment methods included gravity concentration and flotation in most cases. Results were sometimes unsatisfactory, particularly when the ore was too fine grained for liberation of the minerals within economical grinding range. The contaminating gangue minerals, such as quartz and iron oxides, were locked with the manganese to an extent that prevented separation of high-grade concentrates with satisfactory recovery. In cases where fairly good concentrates were made, it was at the expense of recovery, a condition typical of low-grade ores.

Jan 1, 1955

By K. J. Maggs

The U.S. Bureau of Mines has investigated the chemical vapor deposition of diamond films on tungsten substrates. The effects of deposition parameters on the adhesion of the films was determined. The films were produced using a hot filament chemical vapor deposition system. Parameters investigated were substrate temperature and methane concentration in the feed gas. Film quality, morphology, and composition were characterized by scanning electron microscopy and Raman spectroscopy. Adhesion testing was performed using an indentation technique, and the results were quantified by relating adhesion to interface fracture toughness. Diamond films with well-faceted crystalline morphology with grain size greater than 1 µm had poor adhesion properties regardless of substrate temperature or methane concentration. Diamond films with smooth morphologies consisting of rounded clusters of small (<0.2 µm) diamond crystallites and amorphous carbon phases displayed much higher adhesion, although the conditions that led to the growth of these films are not understood.

Jan 1, 2010

By K. E. Tame

The Bureau of Mines is studying possible modifications in conventional ore-processing methods that will confine and permit controlled disposal of radioactive liquid wastes. Stream and ground water pollution from radio-active nuclides, principally radium 226 and thorium 230, in liquid wastes from uranium mills can be minimized by reusing the waste solution within the mill. Such reuse of waste solution in an acid leach-resin-in-pulp flowsheet was investigated in the laboratory. The process consists of acid leaching for dissolution of the uranium, sand-slime separation and countercurrent decantation washing for recovery of a pregnant slime slurry, and the use of ion-exchange resin for recovery of uranium from the slurry. Reuse of clarified barren effluent for washing in the simulated mill circuit was carried through 55 cycles. Dissolution of uranium from the ore averaged 97.5 percent. Washing efficiency of 99.9 percent was attained when using 4.35 volume tons4 of combined barren effluent and makeup water per ton of ore. Absorption of uranium from the pregnant slime slurry by an ion-exchange resin averaged over 99.9 percent.

Jan 1, 1962

By R. V. Ramani, R. Bhaskar

"An airborne dust cloud is an ensemble of particles of varied size, density, shape and states of aggregation. An understanding and quantifying of the dispersion and deposition of the du.st generated in mines is essential to the development of measures for reducing worker exposure to dust.In coal mining, the major portion of the dust is generated during the cutting of coal using a shearer or a continuous miner. The major phenomenon affecting ambient concentration is the deposition of dust. Panicle deposition may take place due to the effect of gravitational, inertial, electrostatic, and thermal forces, and mechanisms such as Brownian and eddy diffusion and inenial impaction. The three major mechanisms of deposition in turbulent flow in mines are diffusion (Brownian and eddy), sedimentation and inertial impaction. The mechanisms determining panicle deposition are size dependent.From a review of the literature, there appears to be a knowledge gap in the understanding of the deposition phenomena in mine airways. In order to obtain a better understanding of the deposition of dust for various particle sizes, and to develop a set of data for evaluating predictive mathematical models/or dust flow in mines, a series of dust-flow experiments was performed under controlled conditions in mine airways. It appears that the deposition data generally follow the theoretical behavior of dust based on the combined effect of diffusional and gravitational deposition. Jn this paper, the findings of the study on the deposition of dust in mine airways and its dependence on size, velocity and concentration are discussed. A set of deposition equations that could be used to determine the approximate deposition at various points in a mine airway are presented.IntroductionThe major factor affecting ambient dust concentration in mine airways is the deposition of dust. Particle deposition may take place due to the effect of gravitational, inenial, electrostatic, and thermal forces, and mechanisms such as Brownian diffusion, eddy diffusion and inertial impaction. The major mechanisms of deposition in turbulent flow in mines are diffusion (Brownian and eddy), sedimentation and inertial impaction. Inertial impaction is significant only during changes in direction, but the change in direction of flow with resultant powerful eddies may cause increased re-entrainment of the particles, thus having a compensating effect. While the literature in aerosol sciences contain several references on deposition, most studies were done in small diameter tubes for diffusional deposition (Liu and Agarwal, 1974). The deposition data from small diameter, short tube experiments may not be applicable to studying deposition in mine airways that have large areas and extend several hundred meters. Further, the change in concentration along the length of a mine airway may significantly affect the deposition an aspect that may not be easily determined in short tubes in laboratory experiments."

Mar 1, 1992

By E. C. Tarpley, H. M. Cooper, R. F. Abernethy

"INTRODUCTION The determination of moisture in coal is an empirical test, because the time, temperature, and equipment are specified. The essential features of the equipment, and details of the procedure are given in A.S.T.M. Designation: D271-44 5/. According to the specifications, the following features should be incorporated in the equipment used:1. Oven must have uniform temperature in all parts.2. Oven must be constructed with minimum of air space.3. Oven must have means of changing the air two to four times per minute.4. Air must be dried over sulfuric acid (sp. gr. 1.84).The analytical procedures governing most of the nation's coal purchases are those given in A.S.T.M. Standards referred to above. These standards are general and of such scope as to cover all ranks and types of coal. In cases where only the moisture is required, a faster method than the standard procedure is desired.The semi-automatic moisture tester manufactured by the Brabender Corp. has proved itself in many industrial processes where the rapid estimation of moisture is of vital importance. With the approval of A. C. Fieldner, chairman, A.S.T.M. Committee D-5, and through the courtesy of Lowell Malan, chief chemist, United Electric Coal Companies, who loaned the tester, tests were made to determine the feasibility of using this instrument to determine the moisture in coal."

Jun 1, 1948

By William L. Crentz

1. SALES PUBLICATIONS

Nov 1, 1949

By W. D. Riley

The U.S. Department of the Interior, Bureau of Mines, has been conducting minerals recovery research in support of the nation&apos;s geothermal program since 1974. The Bureau&apos;s program of laboratory and field studies has focused on determining the materials of construction for geothermal resource recovery plants and an the recovery of mineral values from the geobrines. An analytical program has been conducted at the Avondale Research Center to determine the chemical constituents of some high- and low-salinity geobrines found in the Imperial, Valley of California. Data are reported for the early stages of brine production of femur geothermal wells--the low-salinity, medium-enthalpy brines from the East Mesa Known Geothermal Resource Area (KGRA), Mesa 6-1 and 6-2, and the high-salinity, high-enthalpy brine from the Salton Sea KGRA, Magmamax 1 and Woolsey 1. The reported results indicate the importance of the operating and engineering history, the operating parameters during sampling, and the method of sampling in order to evaluate the chemical analyses.

Jan 1, 1980