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By D. Bienstock, R. C. Kurtzrock, E. R. Bauer, J. H. Field

To remove hydrocarbons and carbon monoxide in automotive exhaust by oxidation , a catalyst of 4.2 percent Uз Og , 1.7 percent Cr₂ 0 , and 1.7 percent CuO supported on 1 /8 - inch y- alumina spheres was tested in a reactor in place of the muffler of a 1 / 2 - ton truck . Tests were made with both nonleaded and leaded gasolines . With the engine at operating temperature , tests were made with the engine idling and with the vehicle cruising at 30 mph . Auxiliary air was added to maintain an oxygen concentration of 3 to 4 percent in the gas leaving the catalytic reactor . The vehicle was operated for 83 hours (about 60 percent of the time with the engine idling ) and 525 miles with nonleaded gasoline . Conversions of 98 percent of the hydrocarbons and 100 percent of the carbon monoxide were achieved with the engine idling and with 7,000 ppm carbon atoms and 4- percent carbon monoxide in the feed to the reactor . Hydrocarbon conversions of 75 percent were obtained at cruising speeds of 30 mph with a feed of 1,700 ppm carbon atoms ; the carbon monoxide concentration was less than 0.3 percent in the feed and was unchanged in passage through the reactor . Identical activity was obtained initially in switching to a gasoline containing 1.9 ml tetraethyl lead (TEL) per gallon . However, there was a gradual loss in activity thereafter . Conversions in tests with the engine idling about 50 percent of the time , had decreased by 23 percent for the hydrocarbons and by 25 percent for the carbon monoxide from their initial values after 122 hours and 1,300 miles of operation with leaded gasoline . The levels of radioactive materials in the exhaust of the reactor and the radiation in the vehicle were negligible .

Jan 1, 1963

By Oliver C. Fursman, Lloyd H. Banning

This research was undertaken to determine the feasibility of producing steel from hydrogen - reduced , pyrophoric iron powder . Before steelmaking tests were begun , investigations were made to develop procedures for handling the pyrophoric powder safely , and melting tests were made in a single - phase , electric - arc furnace to determine inert gas requirements for preventing powder oxidation . Steelmaking tests were conducted in a conventional electric - arc furnace , usually by a two - slag basic procedure . Results of the research indicated that ( 1 ) pyrophoric powder can be handled safely and can be prevented from oxidizing excessively during charging and melting in electric - arc steelmaking furnaces ; ( 2 ) little , if any , more electrical energy is required for melting Cerro Bolivar iron powder per unit of contained iron than is required for melting heavy melting scrap ; ( 3 ) high - quality steel can be produced readily from high- grade iron powder , having recoveries up to 95 percent of the total iron ; ( 4 ) steel can be produced from simulated titaniferous , chromiferous , and manganiferous iron powders ; and ( 5 ) the electrical energy required for melting increases with increase in the proportion of slag - forming constituents in the furnace charge .

Jan 1, 1964

By S. J. Pearce

The need for a simple, very sensitive, and accurate method for the determination of benzene in blood and urine vas evident throughout a recent study of chronic benzene (C6H6) poisoning conducted cooperatively by the United States Bureau of Mines, The Barrett Company, and the producers of benzene. A combustion method which will be described in a later publication, and a previously described/ adaptation of Smyth's method were developed and used during that investigation. The adaptation of Smyth's method gave satisfactory results when dealing with exposure conditions that produced chronic poisoning in a comparatively few days, but it was time-consuming; and lacked the accuracy necessary for a study of the absorption, distribution, and fate of benzene in the body during exposure to threshold concentrations of benzene vapor in air. The combustion procedure was satisfactory from the standpoint of sensitivity but was cumbersome, intricate, time-consuming, and required the use of special and somewhat expensive Physical and chemical apparatus. Following the termination of this study of chronic poisoning, possibilities ides for developing better methods occurred, and these have been investigated by the Bureau of Mines with the aid of Relief Works Division personnel microcolorimetric method for the determination of benzene in air has been described recently.6/ The present report deals rich the adaptation of this new colorimetric method to the determination

Jan 1, 1936

By E. M. Tignor

A research program to aid development of improved methods for increased production of petroleum from partly depleted reservoirs is a vital part of the Bureau of Mines effort to effect true conservation of that mineral resource. This report presents results of an investigation to identify the clay minerals within some Appalachian petroleum-reservoir sands, the effect of clay content on the fluid-flow behavior of those sands, and the use of brines in water-flooding operations. Permeability measurements using kerosine, calcium chloride brine, simulated oilfield brine, potassium chloride brine, sodium chloride brine, and distilled water were made on reservoir-rock cores. Clay fractions were separated from sand grains of disaggregated portions of each core sample, and the clay minerals were identified by the differential thermal analysis method. Relations of the permeability to various fluids were developed.

Jan 1, 1957

By Allan J. Clark

This paper, describing the milling practice of the Homestake Mining Co., is one of a series being prepared by the Bureau of Mines. The author acknowledges the assistance of T. G. Chapman, one of the consulting engineers of the Bureau of Mines, in arranging this paper for publication.

Jan 1, 1931

By R. L. Hopkins

Fifteen alkyl cycloalkyl sulfides and three dicycloalkyl sulfides were synthesized to provide reference compounds in the search for these classes of sulfur compounds in crude oils. In synthesizing sulfides by alkaline alkylation the order in which the reactants were added was shown to determine the yield and purity of the product.

Jan 1, 1966

By G. R. Hopkins

A recently completed survey , made by the Bureau of Mines to determine the trend of fuel consumption at refineries in the United States , showed the following outstanding points : A decrease in the use of oil for fuel in 1927 of over 5,000,000 barrels as compared with 1926 ; a decrease in the use of coal of over : 1,000,000 short tons ; small increases in the use of both natural gas and refinery gas ; an increase in the use of petroleum coke . The decrease in fuel - oil consumption was approximately 2,000,000 barrels each in the Atlantic Coast , Texas , and Louisiana- Arkansas districts , with an increase of 1,000,000 barrels in the Indiana - Illinois district , or a net decrease of 5,000,000 barrels . The decrease in fuel- oil consumption by refineries in the Texas and Louisiana- Arkansas areas was offset largely by increased consumption of natural gas and refinery gas , whereas the increased consumption in the Indiana- Illinois region was more than offset by the decrease in coal consumption . The use of coal for fuel declined from 6,052,000 short tons in 1926 to 5,031,000 short tons in 1927. Practically all of this decrease was recorded in the Appalachian and Indiana- Illinois districts , which at the same time showed the largest percentage increase in the use of oil for fuel . It is probable , therefore , that although coal prices also fell off , a considerable quantity of oil replaced coal in this area in 1927. In addition , the group of refineries , which are by location more or less definitely committed to the use of coal for fuel , undoubtedly succeeded in saving a material amount of coal through the use of more efficient fueling methods . A total of 130,815,000,000 cubic feet of natural gas was consumed for fuel at refineries in 1927. This represents an increase of 8 per cent over the 1926 total . Nearly all of this increase resulted from the opening of a line from the Monroe field to Baton Rouge , La . Had this line not been opened , there would have been a decrease in the use of natural gas , as a number of districts , particularly the Rocky Mountain , reported decreases in its use . The use of refinery or still gases for fuel did not change materially during 1927 , there being a total of 52,807,000,000 cubic feet burned as compared with 52,077,000,000 cubic feet in 1926. Refinery gases are largely a product of cracking and , it was probably more than a coincidence that a few districts in which cracking slowed down in 1927 also reported less refinery gas used as fuel .

Jun 1, 1924

By J. L. Reuss

The Bureau of Mines derived information on the softening characteristics of both unfired and indurated iron ore pellets as measured by hot compression strength in a laboratory study. A surprisingly high hot strength (240 1b per ½ -inch spheroid) was developed by unfired magnetite pellets near 900° C; lesser maxima were developed by pellets made from hematite and specularite concentrates near 1,000° C. Those from goethite remained weak throughout the pre induration heating. Fully indurated commercial pellets retain a high resistance to softening when heated in air. On the contrary, in a hot reduing atmosphere their high cold crushing strength dissipates rapidly. At 1,000° C, for example, the average compression strength of seven different commercial pellets was 110 lb; at 1,100° C, the hot strength was only 60 lb. After a rather sharp initial drop, the loss of strength with increase of temperature was gradual. There was no sudden collapse, nor any significant difference, in behavior of commercial pellets whether made from magnetite or hematite concentrates.

Jan 1, 1968

By F. P. Haver

The Bureau of Mines has investigated the electrochemical reduction of lead chloride as a method for producing lead without the pollution problems associated with smelting. It was determined that high-purity metal (>99.9 pct Pb) could be obtained, using PbC12 prepared by ferric chloride leaching of galena concentrate: PbS + 2FeCl3?PbCl2 + 2FeC12 + S°. Optimum results in small-scale electrolytic tests were achieved with a bath consisting of 40 to 70 wt-pct PbCl2 dissolved in KC1-LiCl eutectic, an operating temperature of 450° C, a current density of 2.5 amp/in2, and an electrode spacing of 0.5 inch. In large-scale tests made to develop a cell design for commercial application, the optimum electrode arrangement proved to be a bipolar configuration with horizontal plates. This gave a current efficiency of 86 pct with an energy requirement of 0.52 kwhr/lb lead. To determine the effect of impurity buildup in the bath, 1,200 lb of PbC12 prepared by ferric chloride leaching of galena concentrate was electrolyzed over a period of 2 months. Little deterioration of the metal quality occurred in that time; all of the lead produced had a purity equal to or better than corroding grade (>99.94 pct Pb).

Jan 1, 1976

By Jack G. Croeni

The Bureau of Mines developed a method to extrude low-density tungsten powder billets into rods and sheet bar with high-energy-rate forming equipment. Billets were compacted and sintered in an atmosphere of hydrogen to obtain a density of approximately 60 percent. Extrusion was conducted at reduction ratios of 6.25 to 1 and 9 to 1 at 1,800° C to prod e high-density, sound material. Yield strengths obtained were higher than those of material produced by conventional powder-metallurgy techniques, but ductility was lower at high temperatures.

Jan 1, 1966

By D. A. Rice

As part of its mission, the U.S. Bureau of Mines continues to develop technologies that will enable cost-effective compliance with environmental requirements. To this end, investigations to improve the kinetics of chalcopyrite dissolution by simultaneous grinding-leaching in ferric sulfate solution were conducted using the Bureau-designed turbo mill. The development of such a hydrometallurgical process would provide a nonpolluting alternative to conventional smelter technology. The effects of mill rotational speed and volume percent solids on the leaching time and energy required for copper extraction from chalcopyrite were evaluated. The results of this laboratory study have shown that the simultaneous grinding-leaching of chalcopyrite concentrate using the turbomill is technically feasible with essentially 100 pet extraction of copper being possible at 90° C. An optimal energy consumption of 1,153 kW?h/st of copper leached was found in batch testing with the mill operating at 400 rpm with a slurry containing 35 vol pet chalcopyrite. This energy consumption, while higher than other proposed leaching processes (about 600 kW?h/st), is of the same order of magnitude. Further refinement of the energy requirements would require additional testing using a continuous circuit. Leaching times of less than 1 h, for 80 pct copper extraction, are achievable using the turbomill grind-leach process.

Jan 1, 2010

By John E. Husted

Quantities of kaolin in Georgia in-contiguous or single bodies had been established by previous work to be sufficient for an alumina industry. The need for characterization of this kaolin to determine its suitability as an ore of aluminum resulted in the studies described herein. It was determined in an area roughly 7 x 27 miles, known as the Wrens district that approximately 5.9 billion short tons of kaolin averaging 35.55 percent A1203 exist in an essentially continuous clay body. The Macon-Sandersville district consists of discontinuous kaolin bodies averaging 35.28 percent A1203 with an average thickness of 28 feet. Tonnages for this district are not available. One hundred and twenty core samples of kaolin were analyzed for K20, CaO, MgO, Al203, T102, Cr203, Fe203, Si02, P205, and F. The P205 and F were analyzed by wet chemistry methods and the others by electron microprobe. Seventy-nine of the samples were from the Wrens district forty from the Sandersville-Macon district and one from the Andersonville district. Emission spectroscopic analyses were also made to qualitatively determine all elements present for each core. X-ray diffraction studies were made of each core to determine mineral species present. Scanning and transmission electron microscope pictures also are given for each I' core sample. Elevations, overburden thickness, and kaolin thickness are given for each core site as well as map locations. Isopachs for over-burden and kaolin thickness are given for the Wrens district.

Jan 1, 1983

By Lucia Kuizon

The Antimony RARE II area is underlain principally by Mesozoic igneous rocks associated with the Sierra Nevada batholith. The San Andreas fault zone is near the southern boundary. Metallic mineral deposits are associated with the fault zone. These deposits were formed from magmatic solutions, and tend to be along shears and fractures within the country rock. Marble and dolomitic marble deposits occur in Paleozoic roof pendants or inclusions in the Mesozoic intrusive rocks in the area (Troxel and Morton, 1962, p. 52).

Jan 1, 1982

By R. W. Hiteshue, C. O. Hawk, H. H. Ginsberg, M. D. Schlesinger

The Bureau of Mines studied single - step catalytic vapor - phase hydrogenation of oils derived from coal and oil shale . Treatment of middle oil , from hydrogenation of bituminous coal , gave good yields of gasoline with a German - made molybdenum- zinc - chromium catalyst . The Bureau also achieved good results with duplicates of this catalyst made from domestic raw materials . In one set of experiments with the German catalyst , 38 to 52 wt pct of feed was converted to gasoline . The total liquid product was 91 to 98 wt pct of the feed . Not all this gasoline can be claimed as production , however , because about 20 pct of the feed was in the gasoline range , and part of it undoubtedly survived the hydrocracking treatment . Hydrogenation of crude shale oil in the presence of cobalt molybdate catalyst produced a total liquid product of 89 wt pct of feed . The hydrogenation converted 27 wt pct of feed to gasoline and 44 wt pct of feed to diesel fuel . The remaining liquid product , 18 wt pct of feed , was residue boiling above diesel fuel . The gasoline was of poor quality , with an octane number of 39.1 . The overall product seemed a suitable feed stock for a conventional refining operation . Coker distillate hydrogenation , using a cobalt molybdate catalyst , gave a total liquid product of 97 vol pct of feed ; of this product 60 vol pct was jet fuel and 40 vol pct was diesel fuel . High nitrogen and sulfur in all three of these raw materials severely poison the usual refining catalysts . Thus , the common objective in these

Jan 1, 1964

By John R. Hoskins

Uniaxial compressive strength of rock is usually determined in the laboratory from cylindrical samples that vary in diameter from 5/8 to 8 inches, using a spherically seated compression head of unspecified size. The Bureau of Mines conducted a series of tests on limestone, marble, sand-stone, granite, and plaster of paris to determine the influence of the spherical head sizes and the specimen diameters themselves on the uniaxial compressive strength. Cylindrical samples of several different diameters of each rock type, all having a length of twice their diameter, were prepared and broken using at least three different diameter spherical heads. Analysis of the data shows that spherical head size does not significantly affect the uniaxial compressive strength of cylindrical rock samples. However, the diameter of the rock specimens does significantly affect the uniaxial compressive strength. Within the range of specimen diameters tested, a coefficient of variation of 6.4 percent for plaster of paris can be attributed to the selection of specimen diameter alone. Similarly, a maximum coefficient of variation of 4.7 percent for the rock types tested can be attributed to the specimen diameter alone.

Jan 1, 1969

By Raja V. Ramani, Wilson Miola

"The potential health effects of quartz-bearing airborne dust in mine and mill atmospheres point to the need for the quantification of quartz content in the source material for determining the source-sink relationships and for choosing applicable control measures. While a standard method exists from a regulatory point of view for the sampling of coal mine atmospheres for determining (i) respirable dust concentrations and (ii) the amount of quartz in the samples, there is no generally accepted standard method for quartz analysis in bulk samples of coal and host rocks. Generally, the bulk sample is reduced to a powder for producing quartz analysis samples. Extensive controls arc necessary to ensure representativeness of the analysis samples when these are very minute fractions of the bulk samples. Since the amount of analysis sample is not limited, alternative methods for quartz analysis may also be tried. It is, however, necessary to adopt a procedure which will satisfy several statistical requirements to guarantee representativeness of the quartz analysis samples.In this paper, the important factors in the preparation of quartz analysis samples from the host rocks and bulk samples are discussed. The method developed to prepare the analysis samples is outlined. The results of application of the procedures are presented. The procedure developed for quartz analysis sample preparation is based on sound statistical foundations. The procedure has been validated for reproducibility and homogeneity.The current methods used for quartz analysis in powders are the P-7 infrared spectrometry and quantitative X-Ray Diffraction (XRD). Both have similar restrictions concerning the sample characteristics and operational problems, which arc intrinsic to radiation beams, device geometry, mechanics and controls of the radiation behavior. Although improvements can be made in the spectrometers and diffractometers, some of the most important steps are the procedures for analysis sample preparation from bulk samples and for calibration of the instruments. The sample preparation process is often referred to as one of grinding and sizing the bulk sample to generate the powder for the scanning devices. The particle sizes are referred to and their influence emphasized but the representativeness of the sample is assumed. Assuring sample representativeness during the sample preparation procedures is critical.For the sampling of airborne respirable dust in coal mines, the collection devices, the collection procedures and the analysis procedures are defined. This is not true for bulk samples where weights must be reduced thousands of times to generate the analysis samples for the scanning devices. The specifications to be developed may include bulk sample amount, sample reduction procedures, sample particle size distribution and sample amounts. However, the common problem of insufficient sample amount which is often encountered with mine airborne dust samples need not exist for bulk samples. Further, the same bulk sample can yield analysis samples for several experiments. The latter, of course, requires sample homogeneity.Three concepts are important in the selection of any procedure for sample preparation and analysis. These arc accuracy, reproducibility and representativeness. The adopted procedure has to guarantee a homogeneous sample representative of the population, a defined level of accuracy and reproducibility. Important statistical concepts are embedded in these requirements, particularly with respect to estimation and dispersion errors. Accuracy and reproducibility are totally different though not independent concepts. Estimation is related to accuracy and the true value. Dispersion is related to reproducibility and is measured by the classical statistical standard deviation of the distribution of a series of measurements or analysis performed over the same lot or analysis sample. The dispersion variance (or dispersion error) does not tell a"

Mar 1, 1992

By Robert H. Ridgway

This circular outlines salient facts regarding the sulphur industry of 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 the public by giving further information in response to individual inquiries. It will welcome comments, criticisms, and contributions of data that may assist in making later editions of this circular more accurate, or in developing more fully the bureau's mineral files pertaining to sulphur. Throughout this paper sulphur is used to designate crude sulphur or brimstone, not sulphur produced from pyrites or' smelter gases.

Jan 1, 1930

By R. Blickensderfer

The laboratory wear testing capabilities of the Bureau of Mines are described, Wear tests are used to support the Bureau?s research efforts toward reducing the wear of equipment used for mining and minerals processing and any wear involving a loss of strategic or critical materials. The emphasis is on abrasive wear because it accounts for most of the wear losses that occur in mining and minerals processing equipment, Spalling wear, caused by repetitive impact in grinding equipment, also is included, Ten abrasive wear tests, including high- stress and low-stress and two-body and three-body conditions, are described: dry-sand, rubber-wheel abrasive wear; Taber Abraser; abrasion resistance of refractory materials; dry-particle erosive wear; elevated-temperature, dry-particle erosive wear; low-angle slurry pot; jaw crusher gouging wear; ball mill wear; pin-on-drum abrasive wear; and high-speed impact gouging. Two repetitive impact tests are described: ball-on-block impact-spalling and ball-on-ball impact-spalling. Test equipment, procedures, and specimens are described, and typical test results are presented and discussed.

Jan 1, 1985

By Curt D. Jr. Edgerton

This study was made to determine trends in fresh water usage by California petroleum refineries, to Forecast fresh water requirements to 1975, and to evaluate water conservation practices. Statistical data used in the study were obtained largely from published sources and from records of selected companies. An adequate sampling of the State's refining capacity was obtained, and the data were extrapolated to the total California refining capacity. A breakdown of the data was then made on the basis of the following refining regions: (1) the Los Angeles Basin and Southern Coastal region, (2) the Southern San Joaquin Valley, and (3) the San Francisco Bay area. An unpublished forecast of crude oil input to refineries by a major oil company operating on the West Coast was used as a basis for predicting fresh-water usage. The 1963 fresh water intake by California petroleum refineries was 84 million gallons per day. This is expected to increase to 128 million gallons per day by 1975. The fresh-water to crude-oil ratio is increasing in all regions except the Southern San Joaquin Valley. At present, the supply of fresh water available to almost all of the State's petroleum refineries, mostly from surface sources and company-owned wells, is adequate, although shortages may develop within the foreseeable future. Present conservation methods are centered around the following four objectives: (1) minimum intake of fresh water of the lowest possible quality commensurate with sound technologic practice; (2) optimum recirculation (3) proper treatment before discharge; and (4) substitution of air cooling for water cooling.

Jan 1, 1965

By Robert J. Brennan, Edward R. Navrocky, John W. Buch

In an effort to establish a highly productive mechanized mining system for anthracite beds pitching between 10 ° and 20 ° , for which conventional mobile equipment is not adaptable , the Bureau carried out an experiment in longwall mining using an Anderton- type drum cutter loader and friction - type yielding steel roof supports . The roof- support system proved to be inadequate for breaking the overhanging roof at the break line supports , with the result that the roof broke over the solid coal . The accompanying subsidence destroyed the continuity of the roof in the work area , and the project was discontinued .

Jan 1, 1964