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By Will H. Coghill, G. Dale Cole

"INTRODUCTION This paper describes a method for the rational sorting of particles by means of a laboratory batch jig. Its purpose is to show that a material can be reliably appraised for gravity concentration without the drudgery of sink-float fractionations.Development of the batch- jig method of testing was incidental to a study of the Birmingham, Ala., red-iron ores now being conducted by the Bureau of Mines in cooperation with the University of Alabama and the ore-producing companies.APPLICATIONOres and coal are commonly tested for their gravity-concentration characteristics by specific-gravity dissections in heavy liquids. The heavy liquid most commonly used for coal is zinc chloride and for ores they are benzene, carbon tetrachloride, acetylene tetrabromide, methylene iodide, and thallium malonate formate. The last is poisonous and corrosive to the skin but is essential for separations in the 3.3 to 4.4 specific gravity range. The last two of these liquids are expensive, and several of them are hard to obtain now.Although it is not suggested that heavy-liquid dissections be eliminated entirely, sometimes a more reliable evaluation of coal and ore can be obtained by other and more simple means. For example, sink-float data were unsatisfactory as a guide to commercial gravity concentration of a red-iron ore because they did not take into account the difference in particle shape of the hematite and gangue and the differences in true and apparent specific gravity of the hematite grains, some of which were porous. For this ore, the batch-jig method of testing herein discussed proved advantageous. Not Only did the batch-jig data give a truer picture of the concentration problem, but only about one-tenth the time of the conventional sink-float tests was required."

Jul 1, 1944

By Peter Krause

This report provides an overview of the worldwide photographic industry and of the applications of photography. It also covers important technological and market trends, with special emphasis on those factors which may affect the consumption of silver in the future. The text is divided into the following eight sections: 1. Principal manufacturers of silver-based photographic products 2. Major product sectors 3. Structure of the international market for silver-based photographic products 4. Silver-bearing raw materials for the manufacture of photographic products 5. Processing of photographic products: recovery of silver and recycling 6. Methods for estimating the use of silver in photographic products 7. Basic function of silver in photography and alternate image capture and recording systems 8. Brief history of photography Silver- based photographic materials are made for many applications that require different photochemical and physical response characteristics and a wide variety of formats and sizes. All of these products are laminates consisting of a surface-treated support and bonded gelatin layers. Two basic types predominate - films and papers. Films have transparent or translucent plastic supports (mostly cellulose tri-acetate and polyester), while papers have mostly a paper core coated with polyethylene resin layers on both sides (RC type). The front layer contains white titanium dioxide to provide high reflectivity and the back layer a matting agent. However, a few so-called fiber base papers are still supplied. These have a high quality paper base coated with a baryta layer ; i.e. a gelatin layer containing white barium sulfate. The manufacture of photographic film and paper supports requires special procedures and equipment, because of the severe requirements for chemical purity, optical integrity and uniformity (see Table 1 on page 10 for a list of the principal makers of film and paper supports).

Jan 1, 1992

By G. W. Reimers

Exothermic oxidation reactions of sulfide minerals can produce self-heating situations in underground mines. If the self-heating is unchecked and the resulting heat is not sufficiently dissipated, the result can be spontaneous combustion fires. This U.S. Bureau of Mines report describes laboratory tests conducted to measure the reactivity of pyrite following treatment with additives to counter its self-heating tendencies. Thermal gravimetric analysis (TGA) and isothermal oxidation procedures were used to obtain information on pyrite ignition and the behavior of pyrite during low-temperature oxidation to ferrous sulfate. The determination of treatment effectiveness was evaluated by adding 5 wt pct of the compound to the pyrite before milling. The resulting samples were then heated in moistened air and after 24 h, the amount of pyrite oxidation determined. Results of these tests indicated that several phosphate compounds reduced the oxidation of pyrite to sulfate to about 50 pct or less compared with the oxidation of untreated sample at 200° C. Cupric sulfate reduced oxidation to about 20 pet untreated sample at 200° C. Sodium, calcium, and potassium chloride reduced pyrite oxidation to levels of approximately 15 pct or less of the untreated sample. Using only 1 pct of sodium or calcium chloride was effective in slowing pyrite oxidation to less than 20 pct of the untreated sample.

Jan 1, 2010

By Errol D. Sehnke

This U.S. Bureau of Mines report provides detailed information on worldwide alumina production capacity by plant and country. The information was compiled from a variety of domestic and international sources and was based on information available to the Bureau through December 31, 1993. Capacity data represent announced installed and planned capacities and do not necessarily reflect a Bureau of Mines judgment of actual plant operating levels or timing of planned expansions, The year-end capacity is the ?nameplate" capacity or estimated production capacity, whichever is larger.

Jan 1, 1993

By M. J. Ferrante

The standard enthalpy of formation, low-temperature heat capacities, and enthalpy increments above 298 K were determined by the Federal Bureau of Mines for synthetic dawsonite [NaA1C03(OH)21. The enthalpy of formation was determined by hydrochloric acid solution calorimetry, with the result ?Hf°298 = -469.4±0.7 kcal/mole. The low-temperature heat capacities were determined from 6 to 307 K by adiabatic calorimetry. Tabulated are low-temperature values of Cp°, S°, and H.-Ho° from 3 to 298 K. The derived entropy at 298 K is S298 = 31.55±0.3 cal/deg mole. Enthalpy increments above 298 K were obtained by copper-block drop calorimetry. Tabular data of Cp°, S°, H°-H°298, -(G°-H°298)/T, ?Hf°, ?Gf°, and log Kf are given from 298 to 477 K. Enthalpies and Gibbs energies of decomposition are also reported.

Jan 1, 1976

By Constantine C. Popoff

During 1946 several limestone deposits near Fortson, Snohomish County, Wash., were examined by the Bureau of Mines. These examinations were part of a long-range investigative program of regional mineral supplies required by the anticipated industrial development of the Pacific Northwest. The .study outlined in the following paper was specifically undertaken to disclose new sources of high-purity limestone and to appraise, their economic aspects. The deposits examined -namely the Galbraith, Climax, and Hi, Hi -are somewhat similar in physical features and geologic environment. They are lenticular and belong to the same formation of metamorphosed sediments that underlies the prominent Whitehorse Ridge.

Jan 1, 1949

By J. B. Cheung

The results of a program to demonstrate the technical feasibility of hydraulic borehole coal mining are presented in this report. The hydraulic borehole method of coal mining involves inserting a hydraulic mining device into a borehole that has been drilled from the surface into the underground coal bed. The borehole mining device issues a jet of water under high pressure, which breaks the coal. These pieces of coal, along with the water, form a slurry, which flows to the base of the borehole where it is pumped to the -surface. Phase I of the program encompassed the design, fabrication and factory-testing of a hydraulic borehole mining device. The program was successfully completed with the field tests being conducted at the Wilkeson-Carbonado Coal Field near Wilkeson, Washington. The technical feasibility of hydraulic borehole coal mining was demonstrated by mining 32 tons of coal at a depth of about 75 ft over a period of 4 hours.

Jan 1, 1976

By Fredrick L. Johnson

In 1986, at the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied 25,640 acres of the 29,680-acre Devil?s Garden Lava Bed, 21,040 acres of the 28,660-acre Squaw Ridge Lava Bed, and 9,100 acres of the 12,600-acre Four Craters Lava Bed Wilderness Study Areas (OR-D01-D02, OR-001-003, and OR-001-022, respectively) in order to evaluate their identified mineral resources. The study areas are located in Lake County, OR, about 50 air miles southeast of Bend. No mineral resources were identified in the three study areas. The areas are almost entirely underlain by recent lava flows. Cinder cones occur in each of the areas; however, the best cinder occurrences are in the Four Craters Lava Bed study area. Slab lava, of facing stone quality, is scattered throughout the Devil?s Garden Lava Bed study area, and to a lesser extent, in the Squaw Ridge Lava Bed study area.

Jan 1, 1987

By C. E. Arthur

The Bureau of Mines has investigated the problem of radioactive contamination using nuclear explosives to fracture petroleum reservoirs in an attempt to stimulate production. It was concluded that some contamination of petroleum products will almost certainly occur. However) the degree of contamination cannot be predicted except by a full-scale experiment) since simulating the problem in the laboratory is economically impossible because of the extremely high temperatures and pressures that must be reached in extremely short time intervals if a reasonable analog is to result.

Jan 1, 1965

By Foster Fraas

The Bureau of Mines investigated a method for calculating values of adsorption energy; the goal was to devise an equation consistent with experimental data accumulated in the investigation of adsorption as related to ore separation processes. Numerical identification of the constants of a previously formulated equation provided an equation by which values of adsorption energy could be calculated. Values thus calculated checked with those obtained by calorimetric measurement.

Jan 1, 1965

By Robert W. Smith

Computation of the thermodynamic properties of the reaction products in the deflagration of explosive gas mixtures has been a most valuable guide regarding the possible kinetic mechanisms of homogeneous combustion processes. Knowledge of the physically possible end states is indispensable for understanding observed deviations from equilibrium in heterogeneous combustion. However such information on dust flames is entirely lacking. To complement a Federal Bureau of Mines study of stationary graphite dust flames burning in pure oxygen,6/ this report gives examples, at atmospheric pressure and room temperature, of composition profiles in an idealized oxygen-dust flame, with both mass and enthalpy being preserved. Similar profiles can be obtained from the data of the paper for elevated temperature and pressure.

Jan 1, 1960

By Philip C. Tully

This Bureau of Mines report contains experimentally determined vapor-liquid equilibria data for a helium-nitrogen-methane mixture with a nominal composition of 15, 60, and 25 mole-percent, respectively. Measurements of the equilibrium phase compositions were obtained by means of a windowed cell, in conjunction with an automated chromatograph and a special analyzer for low helium concentrations. The data presented include a comprehensive table and eight graphs depicting phase compositions, vaporization ratios, and correlations with a previous study of two helium-nitrogen-methane mixtures of different compositions.

Jan 1, 1976

By G. B. Gait

This report is the fourth in a series concerning the Bureau of Mines program for microfilming maps of abandoned mines in the Pennsylvania anthracite region; a catalog of the microfilmed maps of 70 mines in the Western Middle field is presented. Previous reports were catalogs of microfilmed maps of mines in the Eastern Middle field and in the Wyoming and Lackawanna Basins of the Northern anthracite field. Additional catalogs will be published as the microfilming of significant mining areas is completed.

Jan 1, 1971

By A. T. Coumbe

During 1953-55, 31,105 miles of pipe for transporting crude petroleum and refined products was laid in the United States, a total slightly below that of the prior 3-year period, according to data compiled by the Bureau of Mines, United States Department of the Interior. The added mileage consisted of 22,571 miles of new pipe, representing about 2,163,807 tons of steel, plus 8,534 miles of secondhand pipe, equivalent to about 419,849 additional tons of steel. During the 3-year period, 13,069 miles of pipe was taken up. By January 1, 1956, the Nation had 188,540 miles of pipeline, an 11-percent gain over the 1952 total of 170,504 miles. The greater use of larger diameter pipelines indicated in recent surveys has continued, as the mileage for sizes 12 inches and over increased from 13 percent of the total mileage at the close of 1952 to 16 percent 3 years later. Crude-oil trunklines 12 inches and over in diameter gained 24 percent during 1953-55, and these larger lines represented 30 percent of the total mileage compared with 25 percent at the close of 1952. Furthermore, the mileage for crude-oil lines less than 12 inches in diameter declined 2 percent and made up only 70 percent of the 1955 total against 75 percent n the previous survey. Product Lines 8 inches and over increased 43 percent from 1952 through 1955 and composed 70 percent of the total mileage compared with 66 percent in 1952.

Jan 1, 1956

By V. A. Nieberlein

This paper presents the results of research undertaken to recover titanium and columbium by low-temperature chlorination of low-grade columbium-bearing ilmenite concentrates, and to simultaneously remove chlorinated impurities from the volatile chlorides without resort to distillation. Coke-reduced ilmenite was chlorinated at 400° to 500° C., and the resulting TiC14 was free of most impurities before condensation. A heated purification column was used wherein various packing materials reacted chemically or physically with the impurities which passed through them in the vapor phase. A nearly water-white TiC14 product was obtained directly. The principal impurities in the titanium tetrachloride were: 0.02 percent Fe, 0.01 percent V, 0.05 percent A1, 0.04 percent Si, and 0.07 percent Cb. This is a less pure product than commercial TiC14. Most of the columbium was recovered as crude CbC15, requiring further refining.

Jan 1, 1960

By W. H. Ode, W. A. Selvig

"INTR0DUCTIONAccording to the Standard Specifications for Classification of Coals by Rank of the American Society for Testing Materials (A.S.T.M. Designation: D388-38).1/ high-volatile bituminous coals, subbituminous coals, and lignites are classified on the basis of calorific values on the ""moist"", mineral-matter-free basis. The moist basis refers to coal containing its natural bed moisture but not including visible water on the surface of the coal. It is assumed that the natural bed moisture of coal in the ground represents the moisture-holding capacity of the coal when in equilibrium with air at approximately 100 percent relative humidity. This moisture is sometimes referred to as inherent moisture as opposed to extraneous moisture, which wets the surface of the coal.To simplify procedures for determining the moisture-holding capacity of coal it is assumed, for all practical purposes that the moisture content of coal when brought to a standard condition of moisture equilibrium in an atmosphere of 97 percent relative humidity and 300 C. represents the bed moisture of the coal. The A.3.T.M. specifications provide that this condition of moisture equilibrium shall be obtained by bringing the coal to a standard condition of moisture equilibrium at 300 C. in a vacuum desiccator containing a saturated solution of potassium sulfate (97 percent relative humidity) according to the procedure proposed by Stanfield and Gilbart. 4/ No mention is made in the specifications for bringing partly air-dried samples to their natural bed moisture condition probably because of the hysteresis effect that has been noted by various investigators. 5/ In this connection it has been found from sorption studies that the adsorption and desorption curves for lignite are not entirely reversible. The hysteresis effect has been explained by some investigators as resulting from shrinkage of the lignite during drying, which causes a collapse of some of the capillaries, so the dried lignite cannot take up as much water as it held originally."

Apr 1, 1953

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

The standard method of employing preliminary air-drying to determine the moisture in coal has been criticized with respect to the loss of heating value from excessive air-drying. By this method, the coal is air-dried at approximately 10-15° above room temperature with the loss in weight being less than 0.1 percent per hour, and then the residual moisture at 105°C is determined. The total moisture is calculated from these two values.

Feb 1, 1948

By Thomas J. Peters

In 1987, at the request of the U.S. Bureau of Land Management, the Bureau of Mines studied the 350-acre Henry?s Lake Wilderness Study Area (ID-035-077) in order to evaluate its identified mineral resources. The Wilderness Study Area is located in northern Fremont County, ID, approximately 140 air miles north-northeast of Pocatello and 3 miles south of the Montana border. The Wilderness Study Area is near the north shore of Henry's Lake at the foot of the southwest-facing slope of Black Mountain. Archean hornblende gneiss, the main rock type present, crops out northeast of the Madison Range Fault, which trends northwest across the southwest corner of the Wilderness Study Area.

Jan 1, 1988

By D. W. Frommer

As one phase of a general problem of recovering sulfide slimes, mineral-dressing research was conducted on flotation tailing from the St. Joseph Lead Co., Bonne Terre, Mo., mill to recover a significant portion of the residual, finely divided galena. Production of a high-grade concentrate was not part of the immediate objective. Only a reasonable ratio of concentration of lead sulfide slime was sought, since the problem of upgrading by mechanical or extractive processes would be considered in the later stages of this study. The results show that, from a feed material averaging 0.20 percent lead (about 70 percent finer than 400-mesh), a recovery of up to 45 percent could be effected by flotation in rougher concentrate analyzing up to 6.5 percent Pb. These results were obtained by using larger quantities of various xanthates and sodium sulfide than used customarily in mills. Sodium sulfide, which is ordinarily detrimental to flotation of galena, was beneficial in this case.

Jan 1, 1959

By J. B. Gayle

Coke-pushing difficulties have been the subject of much controversy but relatively little scientific investigation. Nevertheless, continuing pushing difficulties can greatly decrease the life of a coke oven and should therefore be considered in the selection of the blend and operating conditions used for coke production. The present Federal Bureau of Mines investigation was undertaken to correlate results of previous investigators and to supplement these results to the limited extent practical by us of an experimental slot-type oven. To this end, pushing pressures have been determined routinely for Tuscaloosa oven tests conducted during the past 10 years. Nevertheless, the accumulated information remains incomplete in many respects, and in view of the recognized inadequacies of the data, publication is now undertaken only because of the scarcity of published information on this important problem and the discontinuation of carbonization studies with this oven.

Jan 1, 1961