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By R. E. Perry

To develop new or improved flotation methods for beneficiating low-grade red iron ores, the Bureau made many bench scale and continuous anionic flotation tests on ferruginous sandstones and calcareous iron ores from the north-eastern part of the Birmingham, Ala., iron district. The ores contained about 21 to 36 percent iron, a to 11 percent lime, and 22 to 64 percent silica. Production of iron concentrates containing 48 to 52 percent iron was technically feasible in batch tests, and the iron recoveries ranged from 85 to 92 percent. In continuous tests 49 to 51 percent iron products were obtained with 80 to 90 percent recovery.

Jan 1, 1962

By Alfred Bellows

The objective of this contract is to design, build and demonstrate a support system to improve roof control in the entries of longwall mines. The objective of this phase has been the detailed design of such a system and the selection of a test site in which to perform the pilot demonstration. The result is a complete set of detail drawings or specifications which define the three major components of the system. The Gate Support is a variation of a face chock which has an extended canopy and additional hydraulic legs to protect the region of the face-entry intersection. The Entry Support is a steel beam and hydraulic prop set which is reusable and serves to support the first 100 or more feet of entry inby the longwall face. The Transporter is a bolter-like vehicle with a crane used for installing and retreating the beam sets. The test site selected is CF&I's Allen Mine in Colorado. They presently use simi¬lar steel beams and expect the FMA support system to be more effective as well as recoverable. It is recommended that the completed drawings be used to build a prototype system and test it first in a remote section of the mine and then in the active longwall tail entry.

Jan 1, 1978

By Michael J. Friedel

The permeability and flow capacity in unsaturated media are investigated by the U.S. Bureau of Mines for application to in situ copper leach mining. Moisture retention properties are derived and combined with scanning electron microprobe data to characterize the mineralogy, texture, pore size, distribution, and permeability of the host rock. Finite-element modeling is used to derive a saturated permeability, ambient degree of saturation, and assess various injection-recovery schemes. Recommended design modifications for optimization of solution distribution and maximum recovery from the rock matrix requires either (1) the injection pressures on the order of 1,500 psi and recovery wells operating in a suction mode, or (2) performing permeability enhancement, through in situ rubbling. Injection pressures can be reduced to 500 psi with improved recovery and containment of solutions.

Jan 1, 2010

By W. N. Marchant

The Bureau of Mines performed chemical research to elaborate details of sulfur chemistry pertaining to the citrate flue gas desulfurization process in which sulfur dioxide (SO2), absorbed (as bisulfite ion) in a buffered sodium citrate solution, is reduced by hydrogen sulfide (H2S) according to the overall reaction 2H2S + HSO3 + H+ ? 3S + 3H20. The rate-limiting step in the process was shown to be the reduction by H2S of thiosulfate (S2031-) that is formed as an intermediate. Pseudo first-order kinetic measurements were made at room temperature to retard the reaction sufficiently that adequate analysis was possible. These measurements showed the rates of the following net processes to be -d [S02]/dt (pH 4.5) = (0.409±0.050)min-1 [S02]; d [S2032-]/dt (pH 4.5) = (0.199±0.017)min-1 [S02]; -d [S2032-]/dt (pH 4.0) = (0.0437±0.0265)min-1 [S2032-]~1; -dH2S/dt (pH 3.9) = (21.6±3.0) mmoles/min-atm [H2S]g1.4, where [H2S]g is the partial pressure of H2S in the gas phase, in atmospheres, and the rate describes the consumption of H2S, in millimoles per minute; d[S]/dt (pH 4.0) = (38.0±3.4)min-1 [H2S]1, where [H2S] is the concentration of H2S in solution. Hydrogen ion consumption during the slow phase of regeneration was shown to occur at (2.1±0.5) times he rate of thiosulfate consumption, which is interpreted as evidence for the following as the rate-limiting reaction: 2H2S + S2032- + 2H+ ? 4S + 3H20 A scheme consisting of five sequential general reactions is proposed to account for sulfur formation.

Jan 1, 1981

By H. R. Shell, John L. Miller, M. V. Denny

In the mica research program conducted by the Bureau of Mines at Norris , Tenn . , many micas other than silicon fluorphlogopite have been synthesized . It has been well established since the initiation of the program that synthetic micas are important materials useful for their superior or unique properties as well as substitutes for natural micas . The possibility of controlling the physical properties of synthetic mica by isomorphic substitution of other ions in the fluorphlogopite lattice further emphasizes the importance of these materials . Accurate measurement and reporting of their properties constitute an essential part of the research program . The study of germanium fluorphlogopite is in keeping with the requirements of a comprehensive study on isomorphic substitution , specifically to identify precisely the material -- chemically , structurally , and optically . The X- ray measurements , including indexed powder and single crystal data , with a description of the methods used to obtain these data , are provided . 5 Earlier work on germanium mica by R. A. Hatch et al . (5) gave an estimate of the cell parameters from X - ray powder data , but no attempt was made to index the diffraction pattern or to determine the space group symmetry . Later work by E. A. Schatz and J. C. Withers (9) listed X- ray and optical measurements , but no attempt was made to index the mica or determine its symmetry . Roth (7) found that germanium dioxide having the a - quartz structure , when heated with equimolar percentages of MgO , CaO , Sr0 , or Ba0 at 1,235 ° C , formed ABO3 -type compounds , e.g. MgGe03 isostructural with enstatite (MgSiO3 ) . Geo₂ also has a rutile - type polymorph with Ge ++ ions in octahedral coordination . Germanium was substituted for silicon in the serpentine structure by Roy and Roy (8 ) using hydrothermal techniques . These authors wrote as follows : "The substitution of Ge + for Si + yielded a magnesia - germania serpentine , formed easily in euhedral hexagonal plates which in some instances were visible in the light microscope . Electron micrographs and the sharp X - ray diffraction patterns confirm a plate - like rather than tubular habit . " It has been shown in this investigation that substitution of germanium for silicon in the mica structure is readily accomplished without radically changing the characteristics of the mica . Substitutions in the mica structure take place in three locations : Tetrahedral , octahedral , and interlayer positions . The tetrahedral positions are normally occupied by Sit or by a combination of Sit with Al +3 the most common combination being 2A1 +3 and 6Si +4 · , The octahedral position , which has six - fold coordination in phlogopite , contains a larger cation such as magnesium . In muscovite it contains only 2A1 ions ; therefore , this mica is considered a dioctahedral mica , whereas phlogopite is considered trioctahedral . +3 The interlayer position has twelve - fold coordination with six oxygen ions from each of two adjacent tetrahedral silica layers . This is the cleavage plane of the mica and commonly contains the largest cation in the mica structure (e.g. potassium) .

Jan 1, 1964

By Townsend. James W.

"INTRODUCTION As a byproduct of its mineral investigation program, the Bureau of Mines has developed a number of operating devices and techniques worthy of note. This paper, prepared under the direct supervision of Paul T. Allsman, chief, Salt Lake City Division, Branch, and under the general supervision of Lowell B. Moon, chief, Mining Branch, reports upon one such device. A simple device has been developed for measuring angles of deviation from the horizontal as recorded on a glass tube by acid etching. The device has facilities, also, for measuring the angle between the long axis of the ellipse and the north-south reference points established by a Maas compass or from an established axial lamina, on the tube, which was ori¬ented to a specific direction in the hole by rod alinement.The device was found accurate within half a degree on repeated orientations of the same tube. However, the degree of accuracy is dependent on the accuracy of personal manipulation in orienting the tube to the correct plane."

May 1, 1947

By Sidney Katell

Continuing the series of cost bibliographies which was initiated with the publication of Information Circular 7516 in October 1949, the present report covers the period from January 1959 through December 1959. The abstracted articles, concerned with all facets of cost engineering in the field of petroleum and chemical plants and related facilities, were obtained from the following sources: 1. Bureau of Mines Information Circulars. 2. Bureau of Mines Report of Investigations. 3. Chemical Engineering. 4. Chemical Engineering Progress. 5. Chemical Week. 6. Coal Age. 7. Coal Utilization. 8. Cost Engineering. 9. Industrial and Engineering Chemistry. 10. Nucleonics. 11. Oil and Gas Journal. 12. Petroleum Engineering. 13. Petroleum Refiner. 14. World Oil. On Oct. 16, 1959 a cooperative agreement between the Bureau of Mines and the American Association of Cost Engineers became effective. This agreement provides for the publication of the annual bibliography under the sponsorship of both groups with the work load involved in the preparation divided equally between the two. As a result, the present report partially reflects the efforts of the members of the Association.

Jan 1, 1960

By B. E. Blair

"This report presents the physical properties and related geological and petrographic data of some 84 rock types from operating mines, quarries, or blasting research test sites. These fundamental rock data were collected as a quantitative approach to underground mining problems, blasting research, or other related studies; however, the data are equally applicable to any problem wherein rock characteristics are important factors. Stress-strain curves are given where available, and the standardized procedure for determining elastic constants from static tension tests is described. Computed (laboratory) and measured (field) free-medium velocities are compared in those instances where such data are available. A chart is given showing both the optimum and minimum number of test specimens for the various core sizes employed in the Bureau of Mines standardized physical-property tests. Rock-type, geographical, and geological indexes are included to aid the reader in locating physical-property data in this and previously published Bureau of Mines physical-property reports.INTROD'OCTI ONThis report presents the physical properties of 84 rock types tested from 16 different projects (sections 37-52). Two previous physical-property reports 2-3 / (hereinafter referred to as parts I and II) presented data on 160 rock types from 36 different projects (part I, sections 1-25 and part II, sections 26-36).The physical-property data were originally obtained to supplement structural mining problems, seismic studies, or related investigations; however, they should be equally applicable in all fields of studies where the strength, hardness, or other properties of rock are important factors. The properties, determined from laboratory tests performed on diamond-drill core, include the following:"

Jun 1, 1955

By D. E. Wolfson

As a part of its overall program of coal carbonization, the Bureau of Mines is studying the coking properties of coals that may be used for metallurgical purposes. The objectives of this study were given in detail in a previous report.2/ The inherent suitability of coal for metallurgical use depends primarily on (1) chemical composition, (2) preparation characteristics, and (3) carbonization behavior. The first two factors, as well as the available reserves, are considered in selecting coals for carbonization tests.

Jan 1, 1957

By Harold E. Marr

The computer program XRF4 was designed by the Bureau of Mines to provide for the calculation of several different interelement correction procedures in X-ray fluorescence analysis, including Lachance-Traill, Rasberry-Heinrich, and Claisse-Quintin procedures. The program was written in the BASIC language for timesharing application, and a conversational interaction with the computer is employed during operation. This report presents test problems using data for iron-nickel-chromium alloys and aluminum alloys and directions for use of the program.

Jan 1, 1976

By P. D. Tracy, M. W. Von Bernewitz

"IntroductionA study of 256 coal-mine explosions, which occurred during the period 1909-1924 killed 4113 men and injured 570 others, reveals the fact that there are the critical times of day when explosions are most likely to occur, and when corresponding care should be exercised to guard against disaster. Of these 256 explosions, 83 straight as explosions, 89 were straight coal-dust explosions, and 81 were mixed gas and dust explosions, while three were undetermined.It has been determined from the times given in these reports (in several cases no times were given,that the critical period in the morning ranges between 6 and 9 o'clock when 83 explosions took place with a peal. at 7;30 o'clock. Of these 55 were straight gas explosions, the remainder being either coal dust or mixed gas and coal dust explosions. The critical period in the afternoon or early ranges between 3 and 7 o'clock, when 113 explosions took place, with a peak at 6 o'clock. Of these, 87 wore straight coal-dust explosions the remainder being neither gas or mixed gas and coal-dust explosions. Between these morning and evening periods is one which might be called the noon period - that is, from 11m to 7. p. m. - when 26 explosions occurred while some of these were normal type of explosions - that is, as to causes - others were of unusual cause and character, and. are discussed later. A number of explosions (29 in all) took place during mid-afternoon, late at night, and early in the morning - that is, after midnight."

Sep 1, 1924

By Judith L. Bolis

The Bureau of Mines estimated the potential availability of iron ore from 129 domestic and foreign mines and deposits in 25 market economy countries. The availability of four products on a total and regional basis was determined from demonstrated resources of 75.3 billion It. From the resources evaluated there are a total of 18.6 billion It of sinter fines, 4.9 billion It of lump ore, 14.7 billion It of pellets, and 820 MMlt of pellet feed potentially available at a 15-pct DCFROR, f.o.b. port. On a regional basis, at or below a total cost of $0.26 per iron unit there are 1.7 billion It, 2.8 billion It, and 186 MMlt of sinter fines potentially available from Brazil, Australia, and Africa, respectively. There are 825 MMlt of lump ore from Brazil and 1.4 billion It from Australia potentially available at or below a total cost of $0.24 per iron unit. There are 2.1 billion It of pellets potentially available from the United States at or below a total cost of $0.80 per iron unit, while 442 MMlt are potentially available in Brazil at or below $0.38 per iron unit. South America has 208 MMlt of pellet feed potentially available at or below a total cost of $0.28 per iron unit. While the resources of iron ore are more than adequate to satisfy demand, the future of the iron ore industry is very dependent upon changes in the world economy, and on the domestic scene, changes in the domestic steel industry and steel imports.

Jan 1, 1987

By Sam Friedman

The Bureau of Mines conducted experiments using bench-scale apparatus to explore the effect of large changes in process variables on the yield and composition of the gases produced by passing 800° C steam through a fixed bed of Pittsburgh seam (hvab) coal. The total yield of combustible gases increased throughout the given range for the following variables: Superficial steam velocity increasing from 0.02 to 0.12 fps, pressure increasing from 1,000 to 6,000 psig, residence time increasing from 0 to 60 minutes, and temperature increasing from 800° to 900° C; however, a greater increase in the yield of hydrogen in comparison with the increase in yield of methane reduced the gross heating value of the gas to around 470 Btu per scf at conditions giving the maximum yield. Pressures of 1,000, 3,000, and 6,000 psig at 0.09 fps steam velocity, 800° C, and 60 minutes residence time, respectively, produced methane yields of 20, 24, and 22 percent, based on maf coal, with the gross heating value of the CO2-free gas decreasing from 552 to 520 and to 470 Btu per scf. Methane concentrations in the CO2-free gas were 26, 22, and 14 percent, respectively. Based on the gross heating value of the coal, the percentage of the heating value recovered in the gas was 60, 71, and 87 percent, respectively. The use of tungsten sulfide as a catalyst for converting carbon oxides and hydrogen into methane was explored briefly using both a sulfur-free gas rich in methane and a sulfur-bearing synthesis gas (3H2:1CO).

Jan 1, 1968

By R. V. Higgins

This report presents the results of a study of gas injection in the Upper and Lower Terminal zones in fault block VB and in the Upper Terminal zone in fault block VI, Wilmington field, California. This report is based on data obtained to January 1956. Earlier studies of gas injection in other California fields have been reported .3/ The Upper and Lower Terminal zones, fault block VB, have been producing oil since 1945 and the Upper Terminal zone, fault block VI, since 1948. Before starting the gas-injection project, the expansion of dissolved gas was the principal mechanism moving the oil to the wells. Gravity drainage and an edgewater drive also have contributed to the movement of the oil to the wells. When the gas injection was begun, the reservoir pressure and the oil production had declined appreciably. Gas injection was started in the Upper and Lower Terminal zones, fault block VB, in May 1953 and in the Upper Terminal zone, fault block VI, in October 1953.

Jan 1, 1957

By Richard W. Watson

Card-gap and projectile impact sensitivity data are presented for a wide variety of explosive compositions tested at the Bureau of Mines in more or less standard test geometries. The results of both tests are in good agreement in that they provide the same sensitivity ordering for different subclasses of explosives. Least sensitive were homogeneous liquids that did not exhibit a tendency to undergo low-velocity detonation, ammonium nitrate-fuel oil, and most cast military explosives. Of intermediate sensitivity were pressed and powdered military explosives, cast pentolite, permissible and non- permissible water-based explosives, and one commercial two-component explosive. The most sensitive were permissible and nonpermissible dynamites and explosives susceptible to low-velocity detonation.

Jan 1, 1973

By Otto Ruhl

As the result of a study of an area comprising some 100 square miles in the Missouri-Kansas Zinc district known to have produced zinc Ore from horizons below the Grand Falls formation, it was concluded that these horizons could become an important future source of zinc. To test this conclusion and to ascertain the general conditions associated with these lower-horizon ore deposits, the Bureau of Mines undertook detailed drilling of localities thought to be favorable for deposition of ore in the Reeds Spring and. Fern Glen formations. Two sites in the Galena, Kans., mining camp were chosen for this purpose. Ninety churn-drill holes totaling 19,338 feet of bore were completed by the Bureau in two campaigns that extended from October 1944 to June 1946. Approximately 25 percent of the holes encountered ore and indicated three separate ore bodies containing substantial tonnages. Observations made during the course of the work revealed that certain structural conditions are common to ore deposits in the Reeds Spring and. Fern Glen formations.

Jan 1, 1949

By Paul W. Johnson, Ralph C. Kirby, Frank A. Peters

A series of economic evaluations of processes for producing metallurgicalgrade alumina from low- grade aluminous materials is being conducted by the Bureau of Mines to determine the relative processing costs . The two processes considered in this evaluation are concerned with the recovery of alumina from clay through the formation of ammonium alum . In the first process , dehydrated clay is leached with ammonium bisulfate solution ; in the second process , clay is baked with ammonium sulfate and then leached with water containing a small quantity of sulfuric acid . After the alumina is dissolved by either of these methods , the iron is reduced to the ferrous state to avoid crystallization of ferric sulfate with the alum . The recovery of pure alum requires two crystallization steps . The alum crystals are then redissolved and precipitated with ammonia to produce alumina hydrate , which is calcined to a - alumina . These evaluations are based on published work , and the proposed plants are designed for a capacity of 1,000 tons of alumina per day . The estimated operating cost per ton of alumina for the bisulfate leaching process is $ 117.06 , and for the sulfate baking process , $ 109.26 . Using a Marshall and Stevens chemical equipment index basis of 240.0 , the estimated fixed capital costs , in the same order , are $ 158 million and $ 146 million . Under current economic conditions , these two processes are not competitive with the Bayer process for the production of alumina from bauxite . Since small improvements will not reduce costs sufficiently to approach competitive costs , future research work with these processes should be confined to areas likely to result in major cost reductions .

Jan 1, 1965

By A. Matzick

In its work under the Synthetic Liquid Fuels Program the Bureau of Mines has developed on a 6-ton-a-day-pilot-plant scale a continuous, gravity-feed retort far distilling oil from oil shale. The development work covered by this report was done from January 27, 1950, to January 26, 1952, at the ail-Shale Experiment Station near Rifle, Colo. Over 300 pilot-plant tests were made during the investigation. The basic retort developed has been named the Gas-Combustion retort. In this process, part of the heat for retorting of the shale is generated by burning recycled product gas in a combustion zone within the descending shale bad in the retort. Additional heat is supplied by combustion of the carbonaceous residue remaining in the spent shale after the oil has been distilled. Air for combustion is admitted through an air distributor in the center of the bed at about the mid-point of the retort. Hot gas rising from the combustion zone heats countercurrently the descending raw shale and liberated shale oil by pyrolysis of the shale. After passing through and exchanging heat with the incoming raw shale, the oil is condensed as a fog or mist in the gas, which is withdrawn at the tip of the retort. The cool gas is then piped to an oil-recovery system where the oil is separated from the gas in centrifugal separators or other types of mechanical or electrostatic separators. The hot, spent shale below the combustion zone is cooled by heat exchange with recycle gas, which is a portion of the effluent gas from the oil-recovery system.

Jan 1, 1955

By Joseph S. Coffman

To determine the availability of manganese for metallurgical purposes from selected world resources, the Bureau of Mines evaluated the potential production of contained manganese in concentrates based on the demonstrated resources of 23 foreign and 8 domestic mines and deposits in 9 market economy countries. All but 2 of the 23 foreign deposits are operating mines; none of the domestic deposits are in operation. The demonstrated resources of the mines and deposits used in this study represent an in situ ore resource of approximately 2.2 billion tons," containing 780 million tons of manganese with a total recoverable production potential of 514 million tons of contained manganese in concentrates. The analyses of mines and deposits in this study indicate that about 213 million tons of the contained manganese (41 pct) is potentially available at a January 1981 constant dollar long-run total cost of up to $1.50 per long ton unit (22.4 lb, or 10.15 kg contained Mn), approximately 428 million tons (83 pet) is potentially available at a cost of about $1.75 or less, and 491 million tons (95 pet) is available at less than $3.30. The remaining 23 million tons, which is potentially available at much higher costs (about $8 to $35 per unit), represents the U.S. deposits. On an annual basis, with a cost range of up to $1.75 per long ton unit, the availability from currently operating mines would last at least 80 years based on 1980 world production data. Total manganese production costs are estimated to comprise mining-8 pet, beneficiation-3 pet, transportation-26 pet, and smelting-63 pet.

Jan 1, 1984

By G. E. McElroy

The Coeur d'Alene minim, district of Shoshone County, Idaho, has been one of the largest and most active lead-silver producing districts in the United States for the last 40 years. The mines of the district enjoy exceptional natural advantages with respect to ventilation in that the veins apex high on mountain sides and are most often developed to considerable depths, up to 2,000 feet, by adit and crosscut tunnels under conditions that develop large natural draft pressures; the increase of temperature of the rock with increase of depth from surface in at a low rate; and the average surface temperatures are low. These natural conditions have, in the main, resulted in well-ventilated mines with low temperature conditions throughout. However, where the development has been carried to considerable depths below the lowest level of surface entry, natural-draft ventilation has proved inadequate, and mechanical ventilation systems have been installed on the three largest mines of the district. Local conditions, more particularly those in dead-ended working places, have also required auxiliary ventilation by will fan-pipe units in these and other mines. A particular feature of the district is the number of exceptionally long crosscut tunnels that have been driven to provide entry to vein systems from low points adjacent to milling and transporta¬tion facilities. Three of these tunnels are approximately 2 miles long, and lengths of 3,000 to 8,000 feet are quite common.

Jan 1, 1931