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By J. G. Croeni

The titanium-iridium alloy system was investigated to determine whether alloys of this system would merit further development as control-rod material for nuclear reactors. A study was made to determine the titanium-iridium phase diagram by using melting-point, thermal analyses, X-ray diffraction, dilatometric, electrical resistivity, and metallographic techniques. The titanium-iridium alloy system was investigated between 500° and 2,400° C. Results indicate the formation of two intermetallic compounds, Ti3Ir rind TiIr3, and one intermediate solid solution centered about the 50 atomic percent iridium composition. A eutectic reaction occurs at 1,475° C, and 19 atomic percent iridium. The Ti3Ir decomposes peritectically at 1,520° C. The intermediate solid solution exhibits a maxima of 2,140° C. at 50 atomic percent iridium. This phase is also believed to undergo an order-disorder transformation at 1,750° C. Another eutectic reaction takes place at 2,000" C. and 60 atomic percent iridium. The compound TiIr3 formed at 75 atomic percent iridium decomposes peritectically at 2,115° C. Further increases in iridium content result in the formation of an iridium-rich terminal solid solution. Information obtained below 900° C. in titanium-rich alloys indicates that iridium acts as a beta stabilizer in titanium, and the authors believe that a eutectoid decomposition of beta-titanium occurs near 500° C. and 10 atomic percent iridium.

Jan 1, 1962

By G. M. Wilemon

The Bureau of Mines conducted preliminary investigations on the use of an acid-alcohol leaching technique for recovering phosphate values from phosphate matrices. H2S04 and methanol were used as the leaching agents. Starting-matrix particle size and acid-apatite ratio were found to significantly affect the efficiency of phosphate leaching. Phosphate extractions of more than 80 pct were obtained when minus 200-mesh ore was used and the acid-apatite ratio was 8:1 or more. The iron and aluminum oxide impurities (R203) present in the crude acid products were monitored, and R203-P205 ratios are reported. Phosphate extractions in excess of 80 pct also were obtained when phosphatic clay wastes were leached. Typically, leach slurries filtered using test leaf filters ex-hibited filtration rates of 100 lb/(h·ft2) or more.

Jan 1, 1987

By D. R. Tesarik

An instrumentation and numeric modeling study was conducted by the Bureau of Mines at the Magmont Mine in Bixby, MO. An isolated section of this room-and-pillar mine was monitored with borehole and closure extensometers during a pillar recovery program to determine stress redistribution. In situ stress measurements were taken in the rib before pillar extraction began. Sample cores from the boreholes were taken for analysis of the properties of the host rock in the laboratory. The extensometers recorded no measurable displacements during most of the operation. Two-dimensional, finite-element; three-dimensional, finite-element; and three-dimensional displace-ment discontinuity codes were used to model the area of study. The finite-element models were run with two initial stress conditions, i.e., stress due to gravity only and stress obtained by in situ measurements. Horizontal stresses in the models reduced the calculated factor-of-safety in the mine back by up to a factor of 10, but did not have a significant effect on calculated pillar stability.

Jan 1, 1989

By A. Visnapuu

The Bureau of Mines investigated carbonyl processing techniques for the recovery of the critical metals Ni, Co, Mn, and Cr from domestic primary and secondary sources. In most cases, the source materials require reductive precarbonylation treatment to metallize the contained Fe, Ni, and Co compounds to render them reactive with CO. The critical metals were recovered either by direct conversion to the respective carbonyls or as upgraded products by carbonyl removal of an undesirable metal. Best metal-to-metal carbonyl conversion was under CO pressure, from 80 atm upward, and at 1400 C. Carbonylation was accelerated by the addition of HzS in small quantities. CO pressure, temperature, promoter and pretreatment trends, and other factors enhancing metal carbonyl formation are presented.

Jan 1, 1987

By Rose L. Ballard

This chapter summarizes data on crude nonfuel mineral production for the United States, its island possessions, and the Commonwealth of Puerto Rico. Included also are the tables that show the principal nonfuel mineral commodities exported from and imported into the United States and that compare world and U.S. mineral production. The detailed data from which these tables were derived are contained in the individual commodity chapters of volume I and in the State chapters of volume II of this edition of the Minerals Yearbook. Although crude mineral production may be measured at any of several stages of extraction and processing, the stage of measurement used in this chapter is what is normally termed "mine output." It usually refers to minerals or ores in the form in which they are first extracted from the ground, but customarily includes the output from auxiliary processing at or near the mines.

Jan 1, 1984

By R. B. Prater

Research by the Bureau of Mines includes efforts to devise means for maximum recovery of critical and strategic metals from primary and secondary domestic resources. As part of that effort, the Bureau developed a hydrometallurgical process to recover Co, Ni, and Cu from Missouri lead-smelter matte. The process includes leaching with H2S04 plus Mn02 as an oxidizing agent, liquor purification, selective precipitation of CuS, (Co,Ni)S, and MnC03, and crystallization of Na2S04&apos; This report is concerned primarily with liquor purification, in which As and Fe are removed from the leach liquor by pH adjustment and filtration. Two variations of the purification step are described. One variation provides liquor containing <1 mg/L As and Fe but requires two solid-liquid separations, The other is achieved with only one solid-liquid separation but leads to a lower degree of purification.

Jan 1, 1987

By W. H. Ode

Low-temperature distillation tests at 200°, 350°, and 500° C. were made on a subbituminous coal from Boulder County, Colo., and a subbituminous coal from Weld County, Colo., in connection with a survey of carbonizing properties of American coals4/ and. investigations of their chemical and physical properties.5/ The coal represented by the sample from weld County was reported to give off combustible volatile matter at unusually low temperatures when placed on a fuel bed. The yields of tar and oil and the composition of the gas from this coal, as obtained in the distillation tests, did not confirm this report. These yields and the gas composition of the Weld County coal differed but little from those obtained from the coal from Boulder County. Both coals yielded tar and gas in amounts considered to be normal for coals of their rank.

Jan 1, 1937

By V. Rajaram, S. Bhattacharya, M. F. Dunn

During a mine fire or other emergency, it may be desirable to reverse the airflow in order to provide an escapeway or to isolate a fire. Also, (in colder areas, the airflow may be reversed to prevent ice buildup. When reversing main mine fans, the mine operator usually does not know what operating characteristics of flow and pressure to expect. Laboratory a field tests of vane axial main mine fans in the 7- to 9-ft diameter size range were conducted to establish forward and reverse performance characteristics under controlled conditions and at typical mine installations. The data obtained suggest that reverse performance characteristics are dependent upon the blade angle and the hub to tip ratio. There is also evidence that reverse performance can be predicted for a family of blade angles and a given hub to tip ratio. Generally, quantity of air is 30% to 65% less in reverse than when operating in the normal forward mode.

Jan 8, 1983

By Paul T. Allsman

Iron-ore deposits in southwestern Utah, as the major source of iron ore for western steel plants, were investigated by the Bureau of Mines in 1942-45 in cooperation with property owners and operators and with the assistance of the United States Geological Survey with a view to determining and extending the known reserves. The factual data resulting from that project were presented in a previous report and in a report on the geophysical surveys now in course of publication. The present report has been prepared in response to expressed public interest in the ore reserves of Iron County. Mining began in the district in 1871} but. did not become important until 41 1923. From 1923 to 1946, inclusive) production totaled 10,139,500 long tons. In 1945 the district yielded 1,931,749 long tons containing 52.84 percent iron; in 1946 the corresponding figures were 1,317,671 and 53.75. The deposits lie .in a narrow, 23-mile long belt extending northeasterly from Washington &apos;County into Iron County along a line of mountains, chief of which are Iron Mountain, Granite Mountain, &apos;and Three Peaks in Iron. County. The deposits are hematite-magnetite bodies, chiefly in limestone near its contact with the monzonite of the mountain masses, but with a few important veinlike bodies in the monzonite or at the contact. They range in size from small pods to several millions of tons, and in depth from surface or near-surface to a known maximum of 1,300 feet:

Jan 1, 1948

By Kenneth C. Stewart

Eight brands (three samples of each kind) of commercially available audio-dosimeters were performance-tested. Each unit was placed in an anechoic chamber and subjected to various acoustic signals to measure its A-weighting response and overall integration accuracy. All units met the A-weighting tolerance for type II sould level meters, and six brands were within the Bureau I s overall accuracy requirements of ±2 dbA referred to input.

Jan 1, 1974

By Charles E. Whieldon

This report presents the results of a study on part of the Smithfield oilfield, Wetzel County, W. Va. The primary purpose of the investigation was to determine the original and the present volume of stock-tank oil in the formations and to investigate the feasibility of waterflooding the Gordon Stray, Gordon, and Fourth sands underlying the I. D. Morgan lease. The study was based on laboratory core analyses, geophysical well logs, geologic considerations, and various field prediction data from the I. D. Morgan lease. The Bureau found that, of the three sands cored, the Gordon Sand was the best prospect for waterflooding, and that a properly engineered water flood should recover 136 to 230 barrels of oil per acre-foot from this formation.

Jan 1, 1967

CESIUM metal production increased sharply in 1963. Domestic Production.--Cesium metal was produced by The Dow Chemical Co., Midland, Mich., MSA. Research Corp., Callery, Pa., and by Penn Rare Metals, Inc., Revere, Pa. American Potash & Chemical Corp., Trona, Calif., produced some combined cesium and rubidium. This company, Penn Rare Metals, Inc., and Rocky Mountain Research, Inc., Denver, Colo., produced various cesium compounds. Complete production data on cesium and rubidium and their compounds were not available for publication. Consumption and Uses.-Substantially more pollucite was consumed to produce cesium metal and compounds in 1963 than in 1962 but the overall consumption of pollucite continued to be small.

Jan 1, 1964

By F. P. Haver

A procedure is described for recovering both lead and sulfur from galena flotation concentrate, comprising the following steps: (1) Aqueous oxidation of the concentrate, using ferric sulfate to convert lead sulfide to sulfate and to give elemental sulfur; (2) regeneration of the ferric sulfate by electrolysis in a diaphragm cell; (3) treatment of the leach residue with ammonium carbonate solution to change the lead to an acid-soluble form and to produce ammonium sulfate as a byproduct; (4) solution of the lead carbonate in hydro-fluosilicic acid followed by electrolysis to recover the lead as metal and regenerate the acid; and (5) extraction of the elemental sulfur from the final residue with an organic solvent. About 90 percent of the lead can be recovered by the above method as 99.9-percent-pure metal, together with two-thirds of the sulfur--half in the elemental form and half as ammonium sulfate.

Jan 1, 1970

By Stephen D. Smith

This chapter summarizes data on crude nonfuel mineral production for the United States, its island possessions, and the Commonwealth of Puerto Rico. Also included are tables that show the principal nonfuel mineral commodities exported from and imported into the United States and that compare world and U.S. mineral production. The detailed data from which these tables were derived are contained in the individual commodity chapters of Volume I and in the State chapters of Volume II of this edition of the Minerals Yearbook. Although crude mineral production may be measured at any of several stages of extraction and processing. the stage of measurement used in this chapter is what is normally termed ?mine output." It usually refers to minerals or ores in the form in which they are first extracted from the ground, but customarily includes the output from auxiliary processing at or near the mines.

Jan 1, 1989

By H. C. George

This report presents a comprehensive tabulation of lifting cost data collected from oil companies in many different fields. These data were collected during the writer&apos;s studies of surface equipment and methods of pumping oil wells, in practically all of the important oil fields in the United States and are based on average operating conditions at 57 groups of properties with a total of 4,497 producing wells. Although lifting cost is only a part of the total cost of producing oil, it nevertheless gives a representative cost figure for purposes of comparison.

Jan 1, 1923

By d&apos, Kathleen J. Amico

THIS SUMMARY appears in Minerals Yearbook volumes I and III, which cover mineral production in the United States, its island possessions, the Canal Zone, and the Commonwealth of Puerto Rico, as well as the principal minerals imported into and exported from the United States. The several commodity and area chapters contain further details on production. A summary table comparing world and U.S. mineral production also is included. Mineral production may be measured at any of several stages of extraction and processing. The stage of measurement used in the chapter is normally what is termed ?mine output." It usually refers to minerals in the form in which they are first extracted from the ground, but customarily includes for some minerals the product of auxiliary processing operations at or near mines.

Jan 1, 1965

By W. N. Marchant

The Bureau of Mines improved removal of selenium from zinc smelter acidic gas scrubber effluent by using zinc dust to precipitate soluble selenium prior to lime neutralization. Lime neutralization alone decreased selenium in the waste water from, typically, 6 parts per million to 2 parts per million, whereas the use of zinc dust precipitant gave an effluent containing less than 0.1 part per million of selenium. The waste treatment operation first was developed on a laboratory scale and later was successfully tested at a smelter site on a 1-gallon-per-minute basis. During the research a simple and rapid means was developed for determining selenium in waste water; the technique enabled visual semiquantitative selenium determinations that later were confirmed quantitatively by X-ray fluorescence.

Jan 1, 1978

By T. W. Goodman, J. Cervik

The Bureau of Mines conducted studies to compare the effectiveness of the cross-measure borehole system with that of surface gob holes on two successively mined retreating longwalls in the Lower Kittanning Coalbed. Only the cross-measure system was in operation on panel A; on panel B, both systems were in operation. In addition, the cross-measure bore-holes on panel B were drilled parallel to the face, whereas those on panel A were drilled at a 45O angle with respect to the longwall axis. The studies show that the cross-measure system captured 71 pct of the methane generated by longwall mining on panel A. On panel B, the sur- face gob hole dominated over the cross-measure system for about 700 ft (213 m) after it was intercepted. Beyond that point, the cross-measure system dominated. About 93 pct of the methane generated on panel B was captured by the two systems. Cross-measure boreholes that were drilled parallel to the face were as effective as boreholes oriented 45" with respect to the longwall axis. In addition, they are shorter and require less drilling time. Comparison between observed gas pressure differentials in boreholes and calculated values indicate that boreholes can be shortened further to 140 ft (43 m). Additional studies are needed to verify these calculations.

Jan 1, 1986

By Edward J. Kansa

In a Bureau of Mines study, unsteady, spherically symmetric, one-dimensional, compressible-flow (finite sound speed) equations were solved numerically for a spherical deflagration propagating concentrically in a spherical vessel with Mach numbers ranging from 0.2 to 0.7; trajectory histories agree with the infinite-sound-speed theory developed by Perlee, Fuller, and Saul (PFS). A preliminary result of this study shows that flames propagating with speeds greater than 20 pct the speed of sound in the unburned gas mixture generate a complex history of aerodynamic waves distributed throughout the spherical vessel. Although the average pressure and flame radius agree with those predicted by the PFS models, the aerodynamic waves have a pronounced effect on the flame velocity, differing appreciably from that predicted by the PFS model.

Jan 1, 1976

By Douglas C. Peters, Valois R. Shea-Albin, Dennis R. Dolinar

An accurate assessment of the vertical stress on a coal seam at depth is important for mine design. Vertical stress calculation techniques presently available either are not sufficiently accurate or cannot handle complex surface topography. Therefore, the U.S. Bureau of Mines developed a computerized method to calculate vertical stress exerted on surfaces at depth that includes the effect of topography. Two input data sets are required: a digital elevation model containing topographic elevations and a coal seam file defining coal seam elevations at depth. Boussinesq&apos;s equation then quantifies the vertical stress resulting from topography. The computerized method was tested on a coal seam overlain by a complex topography where a vertical stress map encompassing several square miles was produced. Results show that depth mitigates the affects of surface topography, while the coal seam topography has a direct effect on the vertical stress. In comparison to the computerized method, the direct stress method overestimates stress under hills and underestimates stress under valleys. The largest difference between the two methods occurs under the steepest topographic relief. A limitation of the computerized method is that stresses cannot be accurately determined near an outcrop.

Jan 1, 1992