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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 Bernard M. Larsen, Clyde F. Williams, Edward P. Barrett

"Introduction.The Bureau of Mines at its Northwest Experiment station has been studying the production of sponge iron for the past four years, and during 1923 progress advanced to the point industrial applications can be safely considered. A furnace was operated commercially at silver City, Utah, producing about three tons of sponge iron daily.The Bureau was led to undertake this work by the interest in the use of sponge iron for copper precipitation and for conversion to iron and steel in the electric furnace.If a piece of iron oxide is completely reduced at such a low temperature (850 to 900° C) that no sintering or fusion takes place, then the piece of metallic iron formed has the same size and shape as the original piece of oxide on account of the removal of oxygen, the structure is finely porous, exposing a large surface of iron, and the apparent density is less than that of the original piece of iron oxide. This material is called ""sponge iron"". Chemically, it is a very reactive material."

Nov 1, 1924

By W. D. Dietzman

This Bureau of Mines report presents a profitability analysis of producing crude oil by waterflooding. Included are the estimated costs of installation of water injection and producing equipment for waterfloods at 2,000 and 4,000 feet and the estimated annual operational expenses for each in west Texas. Using these cost estimates as a base for selecting a range of costs that are indicative of producing crude oil by waterflooding, a simulation technique was derived for determining the profitability under various conditions. Because of the large number of combinations of variables used in this study, a high-speed digital computer was utilized for the calculations. The variables include operational expenses, capitalized costs, price of the oil, annual production, and leasehold acquisition cost. The results obtained from the simulations are presented Fn the appendix. In addition, a nomographical approach was chosen for presentation of the profitability. Five nomographs are presented that can be used for fast estimation of the discounted cash flow (DCF) rate of return that might be expected from a prospective or active operation under various sets of assumed conditions.

Jan 1, 1974

By Glenn C. Reed

This report is one of a series describing mineral investigations within the Missouri River Basin in Montana. The primary purposed of these investigations is to provide information to agencies of the Department of the Interior and others concerned with the planning of Federal power developments in the basin. This report is limited in score to consideration of mineral deposits of presumed inventory value within Gallatin County, Mont. The field investigations were made during the fall of 1948.

Jan 1, 1951

By J. E. Hamak

This publication contains analyses and related source data for 266 natural gas samples from 20 States and 2 foreign countries. None of the analyses have been previously published in annual reports. All samples were obtained and analyzed as part of the U.S. Bureau of Mines investigations of the occurrences of helium in natural gases of countries with free market economies. This survey has been conducted since 1917. The analyses published herein were made by mass spectrometer and chromatograph.

Jan 1, 1992

By Franklin H. Persse

Domestic bismuth supply was projected from production figures for the ores in which it occurs--copper, lead, zinc, and tungsten. Published and unpublished data concerning host ores were examined to determine bismuth reserves and resources, and mine production. Potential recoverable bismuth occurring with reserves and resources of copper, lead, and zinc was estimated to be 36.3 million pounds. A bismuth availability diagram was developed from quantity estimates and ratios of production cost to value for these host ores. Additional recoverable bismuth occurring with domestic tungsten reserves was estimated to be 1.5 million pounds. Domestic byproduct production of bismuth will approximate 1.3 million pounds annually by 1980. This quantity will provide about 37 percent of the 3.5-million-pound estimated requirement for that year. Known world supply of bismuth appears to be sufficient for world demand to the end of this century. The study indicates that bismuth reserves and potential resources in the rest of the world have not been adequately reported.

Jan 1, 1970

By Graham W. Marks

In broadening the utility of spectrochemical methods 9f analysis of ore samples 3,4/ a procedure employ in the total energy method, has been adapted to determination of silver in ores. Silver is the first element in group I of the periodic table to be studied in the Bureau of Mines program. Two silver lines in the spectrum, Ag X\ 3280.683 and 3382.89lR were used in the study, and the problems that had to be overcome were: (1) Influence of extraneous elements on line intensities, (2) preparation of standard curves, and (3) improvement in equipment and technique to increase accuracy. Sodium, potassium, sulfur, selenium, iron, cobalt, and nickel yielded low intensities and hence low results, particularly on the samples high in silver, but addition of 60 percent or more of lime counteracted these effects. One calibration curve must be used for samples low in silver and other for those high in silver. The chocks with fire assaying were close enough for preliminary or exploratory investigations, and the method is much more rapid.

Jan 1, 1948

By G. L. Hundley

The Bureau of Mines has devised a procedure to recover chromium chemicals from concentrates derived from low-grade domestic chromites. These domestic chromites contain silicon and aluminum impurities at levels that are too high to permit processing by present industrial processes. The Bureau procedure consists of reacting chromite with molten NaOH under oxidizing conditions to form sodium chromate (Na2Cr04)' The reaction product is leached with methanol to recover the majority of the unreacted NaOH, then with water to extract the Na2Cr04 and the remainder of the NaOH. The Na2Cr04 product is recovered by evaporative crystallization from the aqueous solution. This report presents laboratory results of studies to determine the optimum leaching conditions for the reaction products of several domestic chromite concentrates. Results of solution purification and crystallization studies are also presented. The concentrates are from a variety of sources including the Stillwater Complex in Montana, Red Bluff Bay and the Kenai Peninsula in Alaska, and a Ni-Co laterite from southern Oregon. Sodium chromate crystals were produced that contained less than 0.01 pct NaOH.

Jan 1, 1988

By R. Hogg, J. M. Mutmansky, E. Kaya

"Characterization of the size, shape, chemical composition, and mineralogical content of mine airborne dusts generally requires a larger mass of dust particles than is typically collected using traditional sampling devices. In this paper, the general design of a passive dust collector is described and the field results are presented. The collector was constructed of galvanized sheet metal duct with a resin-coated honeycomb to provide an elutriation-type system for particle collection. Several versions of the collector were used in the field portions of the research.The dust samples collected from underground coal mines were found to possess angular particle shapes, relatively consistent size distributions, and elemental compositions that showed relatively little variation, at least for the more prevalent elements. In addition, the distributions of particles sizes obtained from the passive dust collector appear to be similar to those of samples collected at the same time in a conventional personal sampler except that the passive device seems to collect a larger quantity of coarse, nonrespirable particles. Conclusions on the suitability of this dust collector for collecting characterization samples are presented. In addition, the potential for using such a dust collection system for supplying dusts for biomedical research is discussed.INTRODUCTIONRecently, a considerable amount of research effort has been directed toward better understanding of the characteristics of the coal dust generated during the mining process. It is generally believed that dust characteristics play a significant role in the development of Coal Workers' Pneumoconiosis (CWP). In order to effectively protect coal workers from coal dust, it is important to understand the properties of dust, the mechanisms of generation and dust-lung reaction. Conducting research on dust characterization, dust control and the biomedical aspects of dust toxicology generally requires a large sample of airborne coal dust. Unfortunately, current dust sampling instruments are not able to meet this demand because only a few milligrams of dust are collected."

Nov 1, 1995

By Frank D. Lamb, Lloyg H. Baning

"The crushed-stone industry has long been troubled with the problem of producing a more or less cubical product for use as concrete aggregate. Its seriousness varies widely for each producer, depending upon the character of the rock employed for raw material and the ultimate use of the crushed stone. For many construction uses, such as the macadam or bituminous-concrete- type road, flat pieces are not objectionable and may even be preferable to more cubical rock. However, most specifications for concrete require that the stone must be reasonably free from flat and elongated pieces.The rigid specifications set by many contractors have resulted in the rejection of coarse aggregate that, except for the presence of an excessive amount of flat and elongated pieces, would be entirely acceptable. In many instances, if an efficient, economical method of removing flat and elongated pieces were available, local producers could meet the requirements of the contractor and thus eliminate the necessity for importing more cubical material.A brief investigation of the problem of removal of flat and elongated pieces from crushed aggregate, carried out at the Eastern Experiment Station of the Bureau of Mines, indicated that it is mechanically possible to remove flat pieces from crushed rock.TEST EQUIPMENTA number of mechanical devices are used by the coal industry for separating slate from coal; these depend upon the difference in shape of the crushed slate as compared with the coal. Such devices as shutter screens, spiral separators, and the Norman picker would be suitable for removing flat pieces from crushed rock in the same manner as they are used by the coal industry. None of these devices was immediately available for testing purposes, so an attempt was made to construct a simple device that could be used in commercial operations."

Sep 1, 1944

By Henry Kreisinger, WALTER T. RAY

This bulletin contains a statement of certain results that will be embodied in a report describing investigations of the combustion of fuel made by the United States Geological Survey and the Bureau of Mines in a specially constructed long furnace. The furnace forms part of the fuel-testing plant at Pittsburg, Pa., which was established and equipped by t.he Geological Survey, but passed under the control of the Bureau of Mines on July 1, 1910, when a t.ransfer of fuel-test.ing investjgations, authorized by act of Congress, became effective. The work discussed in this bulletin was done under the direction of the Geological Survey. The furnace was designed and built for an experimental study of the processes of combustiop, this study being part of a comprehensive plan for testing fuels to determine their heat value and the manner in which they can be used to best advantage. Although the main object of the researches made with the furnace by the Geological Survey was to examine critically the production of sensible heat by combustion along the path of the gases rising from the fuel, an interesting as well as important side problem developed in the study of the simultaneous dissipation of the heat through the walls and roof . of the furnace. Thus incidental data were collected on the temperature gradient through the walls at several places. These temperature data. (together with the heat conductivity of the material of the walls) formed the basis for calculating the heat dissipated through the walls. The object of this report is to present and discuss these temperature data. The discussion particularly concerns the air-space type of wall construction as compared with the solid brick wall or walls type, in which the air space is filled with some solid material of low heat conductivity. The conclusion of the authors, which perhaps will surprise some readers, is that, so far as loss of heat is concerned, a solid wall of brick or any ordinary material is preferable to a hollow wall of the same total thickness, especially if the air space in the hollow wall is near the furnace side. There is a general belief that l?ince air is a poor conductor of heat, air spaces built into the walls of a furnace will prevent or reduce heat dissipation through the wa.lls. Although there may be instances of furnace walls in which such construction reduces the rate of heat flow through them, yet as a rule the effect of the air space is just the opposite. While the heat does travel very slowly through the air by conduction, it leaps over the air space readily by radiation. Although this latter mode of heat propagation is common in nature, the laws governing it are not generall;y known and are seldom taken into consideration when furnace walls are being designed. It may be stated here that the quantity of heat passing through a. portion of a solid wall by conduction depends on the difference between the temperatures of the two planes limiting the portion of the wall. The quantity of heat that passes across the air space in the waH depends on the difference of the fourth powers of the absolute temperatUI: es of the surfaces inclosing Hie air space. It follows that, in case the heat. passes by conduction through the solid'portion of the wall, the loss remains approximately the same so long as the temperature of the two limiting planes remains constant, no matter what may be the temperature of the two planes. On the other hand, the heat passing across the air space by radiation increases rapidly with the temperatures of the inclosing surfaces, although the difference between these temperatures may remain constant. This feature will be shown by curves in the latter part of this paper and thoroughly discussed. The important point is that the air space, which is advantageous in the walls of a refrigerator because the temperatures are low, is objectionable in a furnace wall because the temperatures are high. It is customary to put air spaces in furnace walls between the firebrick linings and the common brick. Usually the fire-brick lining is only half a brick thick, which construction brings the air space too close to the furnace. The result is that the temperatures of the surfaces inclosing the air spaces are too high, and in consequence too much heat is radiated across the spaces. The heat passing through such walls would be much reduced if the air spaces were filled with brick, or, better, with some cheap nonconducting materials, such as ash, sand, mineral wool, etc. Even where the fire-brick lining is one brick thick (9 inches), the temperature in the furnace may be high enough to raise the temperatures of the air-space surfaces so much that the heat radiated across the space will amount to more than would the heat conducted through a filling, were the filling only common brick. This last statement is amply justified by the data here presented.

Jan 1, 1911

By R. J. Marek

The number of persons fatally injured in the California petroleum industry in 1931 was 30, a decrease of 20 fatalities or 40 per cent from the number killed in 1930. As a result of the decrease in the number of fatalities for 1931, the fatality curve of the California petroleum industry reached its lowest point in nine years. Although reductions in personnel--which permitted the retention of a select and experienced class of workmen, decreased active field-development work, and curtailed production--undoubtedly have had a marked effect on reducing the number of fatalities in 1931, the decrease also has resulted from continued accident-prevention efforts. Statistics show that a direct relationship exists between development activity and the number of men accidentally killed in the drilling and producing division of the California petroleum industry. For example, when the average number of drilling wells in 1930 was 29 per cent less than in 1929, the number of men accidentally killed at drilling wells dropped 48 per cent; and when the average number of drilling wells in 1931 decreased 52 per cent from 1930, the number of fatalities at drilling wells decreased 58 per cent. The relationship between field-development work and fatality frequency is significant because each year at least 50 per cent of all the fatalities in the California petroleum industry occur in the drilling and producing division. This relationship should serve to guide the accident-prevention efforts of the industry, especially in the drilling and producing division, toward checking an increase in fatal accidents when development activity again takes an upward trend.

Jan 1, 1932

By Mary S. Esfandiary

U.S. scientists attempting to maintain continuous surveillance of scientific information are confronted with two acute problems: The steady, even spectacular; increase in the volume of such information and the fact that much of it is published in unfamiliar foreign languages, According to the National Science Foundation, almost one-third of the world's scientific literature is published in languages that are read by less than 5 percent of U.S. scientists. Most scientists in the United States must rely on abstract journals and translations to obtain information on developments in research and investigations conducted in the non-English-speaking countries. However, there are problems involved in procuring suitable abstracts and translations and in obtaining such information as cheaply and rapidly as possible.

Jan 1, 1961

By W. F. Faragher, W. A. HORNE

Previous interrogation of German scientific personnel by numerous in- vestigators and the examination of evacuated documents indicated that fur- ther information was desirable on a miscellany of products and processes of interest to the Petroleum Industry. Accordingly, Dr. Pier and a large number of other men of the I.G. Farbenindustrie, A.G. plant at Ludwigshafen/ Oppau were further interrogated in July-1945. The information contained in this report supplements that previously reported in the CIOS report of 16 August, 1945: "Report on Investigations by Fuels and Lubricants Teams at the I. G. Farbenindustrie A.G. works at Ludwigshafen and Oppau", edited by Lt. Col. R. Holroyd, (FP).

Aug 1, 1943

By Irving Kabik

Chlorates and perchlorates, when mixed with certain reducing materials, may give a detonating explosive of considerable power. Concerning explosive chlorate mixtures, Guttman3/ states that they "have at all times fascinated inventors on account of the large amount of oxygen stored up in potassium chlorate, which can be given off so readily. When Lavoiser and Berthollet tried to make a chlorate powder in a stamp mill in 1788, they made a great show of it, and even two ladies were present. Unfortunately, after a certain amount of pounding the powder exploded and killed an official and the daughter of the Government commissary, who assisted at the experiments.***. It is interesting to observe how the same old mixtures are proposed over and over again with slight alterations only, in order to qualify for a patent. Potassium chlorate with some carbonaceous matter like charcoal, sugar, starch, glycerin, flour, or sometimes a vegetable or mineral oil and the like occurs again and again." Sprengel explosives, in which some of the undesirable sensitivity of the chlorate was minimized by coating the crystals with a liquid reducing agent, received some attention after a patent was issued to Dr. Herman Sprengel in England in 1871.4/ A somewhat similar explosive, known as Rack-a-

Jan 1, 1945

By K. E. Stanfield

One of the initial projects under the oil-shale research and development phase of the Synthetic Liquid Fuels Act, Public- Law 290, 78th Congress, approved April 5, 1944, was a survey of oil shales of the United States for the selection of a site for an oil-shale demonstration plant. The oil shales were assayed by the conventional Bureau of Mines retort method proposed by Karrick and described by Guthrie in a more recent publication. From previous experience and that had in making these assays, it became evident that the assay method should be modified or replaced by a more satisfactory one. There are several outstanding objections to the Bureau of Mines oil-shale assay method: (1) the oil yields are frequently smaller than those obtained by other types of assay equipment and by commercial retorts; (2) the assayed oil yield represents only a portion of the organic matter in the shale, which under more favorable conditions, may, Jae converted, more completely into oil; (3) the retorting procedure is controlled mainly by trial-and-error methods; and (4) the assay requires approximately 6 hours for completion.

Jan 1, 1949

By Steven A. Fechner

In 1991 and 1992, the Bureau of Mines completed chromium, platinum-group metals (PGM), and tin investigations, and started indium, manganese, titanium, and vanadium investigations in Alaska. These studies were done as part of the Site Specific Minerals Investigations project. As a result of this work, the Bureau found PGM-bearing composite plutons in the Yentna River area of the Alaska Range, which are chemically similar to composite plutons in other parts of the Alaska Range and to Ural-Alaskan type complexes. Previously unknown chromium and PGM occurrences were found in the western Brooks Range. A compilation report on the Bureau's chromium and PGM investigations in the western Brooks Range was also published. Indium was found in anomalous concentrations at the Lost River tin deposit. Small occurrences of manganese were located, mapped, and sampled in the Wiseman and Chandalar quadrangles, and in the Liberty Falls, Prince William Sound, and Homer areas. Tin occurrences in western Alaska were summarized in three Bureau open file reports. The beaches near Cape Yakataga and Yakutat were evaluated for their titanium potential and a sampling methodology was developed. Vanadium investigations included examining streams in the Wiseman and Eagle areas that contained anomalous vanadium values. In the Eagle area, high vanadium, uranium, and copper values were found in the basal layers of the Road River formation.

Jan 1, 1994

By Guy E. Dent, Robert S. Sandford, W. T. Millar, Hugo E. Kuehn

"INTRODUCTION AND SUMMARYDuring the latter part of 1943 a magnetometric survey was conducted by the Geophysical Division of the Bureau of Mines at the mine, Putnam County, N. Y., in an endeavor to locate a segment of the body that reports state was cut off by a fault. The Mahepac mine was abandoned about 1895 after producing nearly 1,000,000 tons of high-grade magetite iron ore. The results of the investigation indicate the termination of the ore body by ""pinching"" or a displacement of such magnitude as to place any extension at a considerable distance the original ore body. This report describes the work done on the project and presents the data obtained. ACKNOWLEDGMENTSThe Bureau of Mines has been investigating deposits of critical and essential minerals in the United States and Alaska since 1939. The Mahopac mine was visited by W.T. Millar, an engineer of the Bureau of Mines, on June 5, 1943, accompanied by Dr. William Agar of the Federal Survey, and again on July 29, 1943, accompanied by Dr. A. F. Buddington and H.F. Hawkes, both of the Geological Survey.The mineral investigation was under the general supervision of Paul M. Tyler, formerly regional engineer, Eastern Region; J. D. Bardill, formerly district engineer; and Dr. F.W. Lee, formerly chief. Division, Geophysical Exploration. The work was done under the immediate supervision of W. T. Millar, project engineer. The Geophysical Survey was made by Hugo Kuehn and Guy E. Dent."

Sep 1, 1948

By M. C. Malamphy

A general description of the activities and results of bauxite investigation by the Bureau of Mines at its bauxite project in Saline and Pulaski Counties, Ark., has been given in Report of Investigations No. 4251. The factual data obtained during the project are reported in a series of Reports of Investigation beginning with No. 4251, of which this is the seventeenth. The data are accompanied by maps showing the location of holes drilled and the deposits developed. Each area upon which work was done is reported by half townships. Each bauxite deposit investigated was assigned a name and a number for ready reference and identification, and its location and name are shown on the appropriate half-township map. The description of each half township is followed by a description of each deposit developed in that half township. The 14 half-township maps and 77 detail maps of the bauxite deposits in this series of reports give the locations and numbers of all the holes drilled on the project, except the deep holes drilled to test the geophysical anomalies. The locations of those holes show on figure 13 in volume 1. The descriptions of the deposits developed are followed by complete detailed logs of the drill holes.

Jan 1, 1948

By D. H. Desy

The Bureau of Mines studied the properties of copper that had been oxide dispersion-strengthened with 2 vol pct of either yttria or alumina. Compounds of copper and aluminum or yttrium, coprecipitated from aqueous solution, were converted to oxides; the copper was reduced, compacted, sintered, and extruded. For the resulting copper-dispersoid composites, room temperature tensile properties after annealing in hydrogen, elevated temperature tensile and stress-rupture properties, and electrical conductivity were determined. Compared with oxygen-free copper, copper-2 vol pct alumina or yttria had improved strength after annealing between 400° and 1,000° C, and improved elevated temperature strength, with little loss in electrical conductivity.

Jan 1, 1969