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By Walter Wood, J. T. H. Cannarella, H. F. Yancey, R. E. Zane

More than 50,000,000 tons of bituminous coal and probably about the same quantity of anthracite are cleaned annually in the United States by wet methods. The water, fine coal, and impurities from the water used for washing ordinarily are recovered by moans of various forms of settling tanks. Settling and clarification may be hastened markedly, thereby greatly increasing the capacity of clarification equipment already installed, by the addition of substances to the washery water that cause the fine particles in suspension to agglomerate and thus settle more rapidly. This phenomenon, although well known and applied in other fields, has been used at only a few coal washeries in the United States. It is widely employed, however, as an aid in the recovery or disposal of fine coal or impurities, as a means of preventing, stream pollution, and to enable reuse of washery water at many plants in Europe. Pioneering work in the United States has been done principally by two companies -- the Pittsburgh Coal Co., in Pennsylvania, 6/ and the Pacific Coast Coal Co., in Washington.

Feb 1, 1940

By Robert D. Ewing

The computer program described in this user's guide provides for the static, three-dimensional, linear and nonlinear analysis of structural and geological systems by the finite element method. The guide describes the capabilities and general features of the program and shows how input is prepared. A number of recent advances in finite element theory and computer technology are incorporated in the program. Nonlinear material properties are provided for, including isotropic, anisotropic, and time-dependent material properties, gravity loading, simulation of a sequence of excavation or construction, and a slip or joint element. The finite elements include beam, rod, axisymmetric and plane quadrilateral, hexahedron, thick shell, and axisymmetric and plane joint. The program also has an automatic mesh generator to minimize user input preparation for continuum finite element meshes.

Jan 1, 1976

By E. H. Burroughs

This bulletin is the fourth in the series of petroleum bibliographies being published by the Bureau of Mines, the three preceding, Bulletins 149, 165, and 180, being compilations for the years 1915, 1916, and 1917, respectively. In this bulletin the same general plan has been followed in arranging the references, but a few changes and additions have been made in the classification, the more important changes being in the classes "Geology and Origin" and "Refining and Refineries." Dl1'ring the year German periodicals were not available, and, as in the bibliography for 1917, references to articles in foreign journals that were not available have been taken' from other sources and credit given to those sources.

Jan 1, 1921

By J. L. Henry

The development and status of technology for producing titanium from U.S. resource materials are summarized in this Bureau of Mines report. Commercially feasible processes and investigations of alternative procedures are reviewed in order to identify techniques that could make existing operations more effective or areas in which future research may lead to the development of new production methods. Procedures are described for producing concentrated titanium dioxide from starting materials such as sands, massive deposits, and mineral processing residues containing rutile, ilmenite, and perovskite; producing and purifying titanium tetrachloride from concentrated rutile, ilmenite, and titaniferous slags; reduction of titanium tetrachloride to titanium sponge metal using metallic magnesium or sodium; purifying and consolidating titanium sponge and scrap by arc melting or induction melting techniques; purifying sponge, scrap, and alloys by molten salt electrorefining; and electrowinning titanium from chloride salts.

Jan 1, 1987

By R. W. Van Dolah

The Bureau of Mines t.ced its investigations into sympathetic detonation of ammonium nitrate (AN) and ammonium nitrate-fuel oil (AN-FO) to define the scaling law for safe separation from detonating AN-FO. Both missile- and non-missile-producing AN-FO donors, weighing up to 5,400 pounds, were employed with acceptors of the same size. The usual cube-root scaling law was not confirmed; exponents for the relationship S = f(Wx) for AN were 0.51 with non¬missile-producing donors and 0.61 for missile-producing donors. For AN-FO an exponent of 0.80 was indicated in the missile-producing case. AN-F0 in polyethylene bags appeared somewhat more easily initiated than bulk AN-FO. The efficacy of barricades in protecting AN charges was investigated. detonation distances were reduced from one-third to one-seventh when filled barricades were employed. The investigation was extended to dynamite with both types of donors. With 1,600-pound missile-producing donors and an equivalent weight of dynamite, initiation would be expected in 50 percent of the trials at 167 feet. The corresponding value in the non-missile case was 67 feet. The data developed in this program of sympathetic detonation will allow the development of a rational set of safe separation distances for AN, AN-FO, and explosives.

Jan 1, 1966

By Richard L. Fowler

Study and development of sensing techniques and sensors were performed to aid shuttle car drivers in detecting obstacles and in guiding the car along the face haulage route. Microwave, acoustic, and optical sensing techniques were considered as part of the feasibility study for obstacle detection. Various guidance techniques, including wire-following and rib-ranging were investigated. Active optical sensing was selected for obstacle detection to obtain the beam coverage and sharp angular cutoff characteristics required within the packaging limitations defined by the shuttle car configuration. Rib-ranging guidance was selected to achieve a completely self-contained shuttle car system which responds to the existing mine geometry without need for wires, stripes, or other path defining devices. Extensive hybrid computer simulation runs were performed to evaluate various guidance techniques during the feasibility study. Subsequent simulation runs were performed to establish parameter values for the rib-ranging guidance system. The obstacle detection and guidance system was designed, fabricated and installed on a standard shuttle car. The system satisfied all applicable permissibility requirements of Schedule 2G. An experimental permit was issued to Bendix for operation in an underground coal mine. System evaluation tests were performed first above ground at the Bendix Research Laboratories. The simulation model was validated by these runs. Final testing was performed underground in an operating mine with an experienced shuttle car driver. All sensors successfully demonstrated the predicted performance capability during underground face haulage tests. Dust did not impair system performance and lens cleaning was not required during working shifts. Further development is required to achieve the desired obstacle detection performance. Closed loop steering control with manual override is recommended for the lateral guidance system. The guidance system should be an invaluable aid to low-coal shuttle car drivers where continuous mining machines are utilized.

Jan 1, 1973

By F. W. Horton

Investigation of an extensive deposit of chromite-bearing actinolite-talc schist situated on the summit of Casper Mountain, 10 miles south of Casper, Wyo., was one of the first projects Undertaken by the Bureau of Mines under the Strategic Materials Act (Public 117, 76th Cong., Ch. 190, 1st sess.), for which an appropriation became available August 9, 1939. During the previous summer; the Geological Survey? made? a magnetometrical survey of the area in which the schist occurred. It was exposed in several small lenses and two larger ones aggregating about 19?acres in area. Although the occurrence of chromite here had been known for many years, the only work done on the deposit was the digging of? a few shallow pits on some of the more promising outcrops. From August 23 to December 3, 1939, the Bureau of Mines investigated the larger of the two main schist bodies. Twenty-four trenches having a total length of 8,073 feet were dug across the deposit, and its subsurface extension was explored by 3,623 feet of diamond drilling. Over 32 tons of samples were shipped to the Metallurgical Division of the Bureau of Mines at Reno, Nev., for reduction, analysis, and ore testing. In all, there were 853 individual samples. Geological maps, based upon examination of outcrops, trenches, and drill cores, as well as a contour map of the area were made by the Geological Survey.

Jan 1, 1949

6784. Barnes, V. L., and Romberg, Frederick. Gravity and Magnetic Observations on Iron Mountain Magnetite Deposit, Llano County, Tex. Geophysics, Menasha, Wis., vol. 8, No. 1, 1943, pp. 32-45. An outcrop of magnetite in the Central Mineral region of Texas is explored experimentally with a dip needle and a gravity meter. Two anomalies are observed, one due to the outcropping body and one probably due to a previously unknown body close to the outcrop. The possible attitudes of the bodies are discussed, and their masses and probable dimensions are computed from the gravitational observations. - Author's abstract.

Jan 1, 1943

By Gerald W. Elger

The Federal Bureau of Mines developed a modification in the conventional Kroll process for preparing high - purity hafnium metal . This modification involved the partial replacement of magnesium by sodium in the batch reduction of purified hafnium tetrachloride to sponge metal . The raw tetrachloride was purified either by thermal degassing of the volatile contaminants to the atmosphere or by fused- salt treatment . In the fused- salt treatment , the tetrachloride was contacted with molten alkali chlorides to remove the impurities . The reaction byproducts were removed from the metal by heat treatment in an evacuated furnace . The metal sponge was consolidated by melting into buttons or ingots , which were analyzed for impurities . The purity of the metal prepared by the modified process is superior to that of the metal produced by the conventional method . The hafnium metal was comparable to crystal - bar hafnium except for the oxygen content , despite the abnormally high impurity concentrations in the raw tetrachloride . Several ingots were successfully cold - rolled to sheet .

Jul 1, 1960

By C. C. Popoff

The Dunkleberg district is in the Flint Creek Range of the northern Rocky Mountains, about 45 miles northwest of Butte, Mont. Silver - lead and zinc mineralization occurs over an area 4 miles long from north to south and 1 to 2 miles wide from west to east. Ore in appreciable quantity has been produced, mostly from the Forest Rose group of mines in the southern part of the district. The Forest Rose mine was the largest producer of lead and the Wasa mine, a mile farther south, the main producer of zinc. The total output of ore from these properties during World War II was 113,000 tons, or 98.2 percent of the total recorded production of the district. The Wasa mine was examined by a Bureau of Mines engineer2/ in 1944. Subsequent investigations during 1946, 1947, and 1948 included trenching and drilling Fn the Wasa area and examination of the Forest Rose and other mines.

Jan 1, 1953

By Laurance L. Oden

Titanium-enriched smelter slag produced commercially by Quebec Iron and Titanium Corp., Sorel, Quebec, was evaluated as feed material for a process developed by the Bureau of Mines to prepare rutile. Glass-forming agents including P205, B203, and two binary mixtures were added individually to the as-received and preoxidized smelter slag, and the nonferrous tramp oxides were effectively partitioned into the resulting noncrystalline phase. Iron in the ferrous oxidation state was moderately soluble in the glass of reduced specimens but less soluble under oxidizing conditions. The solubility of iron oxide in phosphate glass exceeded the solubility of iron oxide in borate glass. Effective conversion of titanium oxide to rutile was not achieved in the high-iron commercial smelter slag, and 20 to 30 pct of the titanium remained as pseudobrookite, a mixed iron-titanium oxide.

Jan 1, 1973

By J. M. Singer

Thermal, mechanical, and physical properties of virgin and heat-treated Pittsburgh seam coal were determined as part of a comprehensive study of combustion of monolithic coal block. The information was sought to help characterize pyrolysis and combustion processes in underground coal mine fires but should also prove useful in the study of in situ and surface coal gasifiers. Measured properties include thermal conductivity, specific heat, thermal expansion, density, compressive and tensile strength, porosity, and permeability. The transport property data were obtained (when feasible) in two mutually perpendicular directions of the anisotropic virgin coal material, and coal samples carbonized for 5 hours at temperatures of 350° C, 475° C, 500° C, 650° C, and 850° C. Other coals (Pocahontas No. 3, Sewell, and Illinois No. 6 seams) were investigated for porosity and relative permeability. Interdependence among all properties was evident from the results; however, only a few correlations could be developed owing to inhomogeneity of coal material and specimen variation, which had the effect of reducing the accuracy of measurement and increasing data scatter.

Jan 1, 1979

By A. L. Engel

In previous reports5/ of ore-testing studies, teats made by established methods on typical ores selected as representative of certain mining districts have been described in considerable detail. In addition to established test procedures, such as screen analysis, Chemical analyses, microscopical examination of ores and products, sink-and-float separation, gravity concentration, floatation, and magnetic separation with or without roasting, it was sometimes necessary to apply other methods, such as leaching, in instances where physical separations were not feasible.

Jan 1, 1940

By A. L. Engel

In previous reports5/ of ore-testing studies, tests made by established methods on typical ores selected as representative of certain mining districts have been described in considerable detail. In addition to established test procedures, such as screen analysis, chemical analysis, microscopical examination of ores and products, sink-and- float separation, gravity concentration, flotation, ,and magnetic separation with or without roasting, it was sometimes necessary to apply other methods, such as leaching, in instances where physical separations were not feasible.

Jan 1, 1940

By H. M. Harris

The Bureau of Mines investigated chlorination of domestic ilmenites in a fluidized coke bed at temperatures of 950° to 1,150° C. Objectives were to develop an effective process for producing TiC14 suitable for TiO2 pigment and to reduce pollution by collecting and treating waste byproduct chlorides. The reactor for these tests was a 10.2-cm-diam quartz tube heated externally by electrical resistance heaters. It contained coke beds of from 35.6 to 82.5 cm in depth that were fluidized by 13 to 25 l/min of chlorine. Ilmenite concentrate powders were introduced at the bottom of the fluid-bed reactor, using the chlorine gas stream as a carrier. Test results showed that greater than 90 pct of the ilmenite reacted at optimum conditions and recovery of TiC14 ranged from 95 to 99 pct of stoichiometric. A temperature-controlled cyclone was used to remove high-boiling-point chlorides such as MnCl2, MgCl2, and FeCl2, and also collected fine unreacted ilmenite and coke dust. Impure TiC14 and FeC13 were separated by collecting the, iron chloride in a condenser con-trolled at 200° C. Titanium tetrachloride vapor was cleaned by passage-through a salt-column filter followed by condensation in water-cooled and refrigerated condensers. Liquid TiC14 was purified further by well-known industrial methods to meet specifications for pigment-grade chloride. Integrated tests were conducted in which chlorine, produced by dechlorination of FeC13 with oxygen, was recycled and used directly in a fluidized-bed chlorinator.

Jan 1, 1976

By Bertrand L. Johnson

Pure talc is a hydrous magnesium silicate (Mg3Si4010(OH)2). Pyrophyllite, although it resemble: talc in certain physical properties and uses, is a hydrous aluminum silicate (Al2Si4010(OH)2) - like kaolin, except that kaolin has a somewhat different composition (Al2Si205(OH)4) and structure. Soapstone can be considered essentially an impure talc grid when pulverized is used for many of the same purposes as talc. Massive, compact varieties of talc often are called steatite. PROPERTIES Talc and pyrophyllite are characterizes; by their softness (hardness on Mohs' scale, 1) their greasy feel, pearly luster, white color, and perfect basal cleavage. They have similar crystal structures, and this similarity explains the close resemblance of the two minerals in physical acid chemical properties. Talc is a good electrical insulator, resists the action of most acids and alkalies, and has an exceptional heat-retaining capacity. Its specific gravity is about 2.7.

Jan 1, 1939

By G. L. Gates

The Bureau of Mines studied the scales formed in producing wells in the Wilmington field, California. The scales were primarily barium sulfate and resulted from the mixing of injected sea water and formation waters; there was excess sulfate in the injection water and the formation waters contained appreciable barium. After breakthrough, the produced brines were supersaturated with barium sulfate. Laboratory tests indicated that barium sulfate precipitated quickly When the supersaturated brines were agitated with crystals of barium sulfate and fairly rapidly when more sulfate solution was added. Precipitation occurred slowly on standing or under nonturbulent conditions. Both the apparent and equilibrium solubilities of barium sulfate in these brines were determined and compared with equilibrium solubilities in distilled water and sodium chloride solutions.

Jan 1, 1965

By Koehler Stout

Previous work done by the authors of this report indicates that hydraulically-placed backfill can be strengthened several fold by various placement methods. Sunshine mill tailings were tested by these placement methods and strength increases up to thirty times were achieved over the ordinary placement methods. A computer simulation study of the test stope in the Sunshine Mine showed that a high-modulus fill absorbs up to 27% of normal stresses versus 7% for "normal" fill while reducing maximum convergence 28% versus 8% for "normal" fill. Although high-modulus fill was not placed in the test stope during this contract, various instrumentation was purchased, designed and built to record necessary data in the stope. Stress gauges were placed in the pillars and recorded data corresponded quite closely with theoretical projections.

Jan 1, 1983

By C. H. McNaughton

The Tennessee Copper Co. operated two mines in the Ducktown district during 1928. The Burra Burra mine is much the larger operation and is the chief source of the ore smelted and treated in the, company's smelter and acid plant rat Copperhill, 4.5 miles from Ducktown. This mine operates steadily and furnishes a regular output of about 40,000 tons per month. The Eureka mine is operated irregularly and produces a much smaller tonnage of high-sulphur ore the rate of output depending upon the demand for sulphur. During 1928 about 60 per cent of the combined output of these mines was shipped directly to the smelter, and the balance was concentrated before shipment in the flotation plant located near the mines. ACKNOWLEDGMENTS The author acknowledges the assistance of Lamar Weaver, Assistant mine superintendent of the Tennessee Copper Co, and of C. F. Jackson, mining engineer, U. S. Bureau of Mines, in the, preparation of this paper, U. S. Geological Survey Professional-Paper 139, by W. H. Emmons and F. B. Laney, has been drawn upon for information contained 'in the paragraphs on history and geology.

Jan 1, 1929

By Robert E. Wallhagen

This report describes the results of a four year investigation into improved face ventilation systems for underground coal mines. The objective was to experimentally determine configurations for a diffuser fan system and a water spray (spray fan) system which will provide a maximum reduction in face methane concentrations without causing an increase in methane concentrations at the operator's position. The experimental evaluation was performed in full scale mock-up mine entries, simulating continuous mining operations in both a six foot and four foot coal seam complete with normal ventilation, water sprays, and methane emission. A limited study was also performed to assess the effect of scrubber discharge location on methane concentrations in the face area. The results indicated that diffuser fan and spray fan systems that were designed to augment the natural airflow pattern in the entry could provide a factor of 3 to 5 reduction in average methane concentration at the face, compared to a mining machine with just conventional water sprays. The properly designed diffuser and spray fan systems also significantly reduced the total methane present in the entry. A properly designed dust scrubber discharge can reduce face methane levels by a factor of two.

Jan 1, 1977