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By L. Allan White

Instrumental analysis is an indispensable tool to many phases of research on rare-earth metals and their compounds; therefore, the development of new and improved instrumental techniques is essential. This report describes an emission spectrometric analytical method using direct-current carbon-arc excitation of various rare-earth-oxide mixtures. Lanthanum oxide serves the dual purpose of an internal standard and a constant major constituent. The versatility of the method was demonstrated by three different applications: (a) Analysis of complex rare-earth concentrates; (b) determination of impurities in high-purity rare-earth oxides; and (c) detection of rare-earth elements in other types of matrices, such as those resulting from beneficiation of rare-earth ores. The average error of analysis in the concentration range of 0.2 to 10.0 percent was 14.6 percent for a group of complex synthetic mixtures of rare-earth oxides. An average error of analysis in the concentration range of 0.05 to 0.50 percent was 21 percent for a group of high-purity rare-earth oxides.

Jan 1, 1959

By D. E. Shanks

This U.S. Bureau of Mines (USBM) research simplified an earlier hydrogen chloride (HCI) leach-sparge process developed by the USBM to recover reduction-grade alumina from domestic kaolin clay. Improvements were made by decreasing the initial leaching acid concentration from 25 to 20 pet, decreasing the leaching time from 1 to 2 h to 15 to 30 min, eliminating the solvent extraction step for Fe removal, and eliminating the step to recover the AI content of the bleedstream circuit. A 10-cycle bench-scale experiment of the simplified process showed that the ferric chloride (FeC13) concentration built up to 9.3 g/L in the recycle stream. This did not interfere with any of the unit operations or final alumina product purity because Fe forms stable soluble chloride complexes when sparged with HCI and is easily washed from the large aluminum chloride hexahydrate (ACH) crystals. The reduced leaching time and acid concentration did not decrease Al extraction.

Jan 1, 2010

By Robert D. Saltsman

Two modes of seal application were identified, and promising state-of-the-art seals of both types -shaft and drum -were selected for initial rating by non-destructive testing. Only one shaft seal survived the initial test, and a search was made for other candidate seals including new seals. One new type of seal was found that gave promising enough operation, as both a shaft and drum seal, to be recommended for installation in prototype wet-head machines.

Jan 1, 1975

By Thomas A. Jones

An impure variety of barite, which lends itself well to the manufacture of heavy drilling mud for oil wells, is widely distributed throughout the Ouachita Mountains in Arkansas. The ore mined in the area and used for drilling muds usually contains an average of 67 percent barium sulfate, although ores as low as 50 percent BaSO4 are occasionally used. Due to the increased demand for barite for drilling caused by the intense search for hew oil occurrences during the years 1945 and 1946, the Federal Bureau of Mines began an investigation of barite deposits in the Ouachita? Mountains in October 1946. In all, 10 barite deposits were examined, trenched, sampled, and studied during the investigation, which was terminated in May 1947.

Jan 1, 1948

By G. A. Savanick

The Bureau of Mines has designed, fabricated, and field tested a water jet cutting device capable of perforating nonmetallic well casings for the purpose of completing or stimulating in situ uranium leaching wells. The device is lowered into the wellbore, where it issues a high-velocity water jet that penetrates either a polyvinyl chloride or fiberglass casing, cement, and from 1 to 4 feet into the surrounding uraniferous sandstone. The resulting perforations allow leaching solution to pass between the sandstone and the wellbore. This report describes the water jet perforator, tells how it is used, presents cost data, and discusses the results of laboratory and field tests. The tests were designed to (1) determine the optimum operating conditions for water jet perforation, (2) assess the effects of changes in these conditions, (3) evaluate the performance of the water jet perforator under actual conditions, and (4) compare this method with other methods of well completion. These tests showed that water jet perforation is superior to conventional well completion methods for selectively achieving communication between the well-bore and adjacent sand while maintaining sand control, for restoring permeability lost through wellbore damage, for stimulating poorly performing wells for completing wells with casings that have inside diameters as small as 2 inches, and for extending the effective well diameter.

Jan 1, 1981

By T. T. Campbell

Although secondary recovery of lead and lead-tin alloys has been common practice in the United States during recent years, there is little published in-formation concerning recovery techniques. Available information does not cover metal recovery from wet dross skimmings. This investigation by the Bureau of Mines was undertaken to develop techniques that would allow lead-tin alloys to be recovered from wet dross skimmings containing large amounts of zinc chloride. A process was developed, on a laboratory scale, for recovering lead-tin alloys from wet solder dross skimmings. Straight water leaching, either with or without a second leaching operation carried out with a Na2C03 addition for removing chloride, produced a dross that could be smelted without further treatment. Overall recoveries averaging 92 percent of the metal values in the dross were obtained in the form of lead-tin alloys, which had an average tin content of 16 percent and lead content of 84 percent. The recovered alloy contained less than 0.02 percent zinc, as determined by both chemical and spectrographic analyses.

Jan 1, 1956

By Thomas J. Peters

The U.S. Bureau of Mines conducted a mineral investigation, and the U.S. Geological Survey did a geological appraisal of an east portion of the Bear-Marshall-Scapegoat-Swan (BMSS) RARE II area (No. A1485) to provide mineral resource information for land use planning. The Bureau of Mines' investigation consisted of a library and field search for all mineral properties and occurrences, and included a review of Teton County mining claim records. Those records showed two placer claims, the only mining-related activity known in the area. Six reconnaissance pan samples were taken in the vicinity of the two placer claims, the Lone Star and Spotted Horse, located on Hannan Gulch in 1900 and 1901. One sample contained a trace of gold, but there are no identified resources. However, the study area is in the Rocky Mountain Overthrust Belt, which is productive for oil and gas elsewhere. The entire study area is blanketed by oil and gas leases and is currently being explored.

Jan 1, 1983

By M. R. Geer, H. F. Yancey

Fuel requirements of the Pacific Northwest have been increased greatly by the war . To the normal peacetime demands for fuel have been added the requirements of new industrial and metallurgical plants engaged in war production , the increased demand arising from expansion of existing industrial establishments , increased amounts of railroad fuel required to handle wartime traffic , and increased quantities of domestic fuel required by the influx of war workers . In the face of these augmented demands for fuel shipments of fuel oil have been curtailed , wood fuel which normally is an important factor in both industrial and domestic markets of the area is less abundant , and the production of coal in Washington has decreased sharply . The fuel requirements of the region have been met so far by shipping large tonnages of coal into the Pacific Northwest from Utah , Wyoming , Montana , and Colorado ; the quantity received from these States and Canada in 1943 amounted to 2,688,9124/ tons , 175 percent of the Washington production . or The proximity of the Washington coal mines to large centers of war production has resulted in widespread migration of miners to employment in shipyards and aircraft plants ; the ensuing shortage of miners largely accounts for the decreased production of coal in the State . Hence , strip mining , which requires relatively few workers and a shorter time for development , offers an attractive means of alleviating the local coal shortage and obviating the necessity of shipping coal from the producing areas of the Rocky Mountain States to the Pacific.coast . So urgent has been the necessity for augmenting local coal production that any coal property that promises to be amenable to strip mining , even though the coal may be inferior in quality , has warranted examination . Even low- grade coals that cannot compete in the normal market can be used locally , thus releasing better coals for shipment to critical centers. of consumption ... One such deposit of low- rank fuel examined by the Bureau of Mines is in western Lewis County , about 9 miles east of Toledo , Wash . The coal is lignitic and on the as - received basis has a heating value of 6,000 to 6,500 B.t.u. per pound . The property is of interest primarily because the physical conditions favor operation by stripping and offer opportunities for low- cost production with very low manpower requirement .

Jan 1, 1945

By L. A. Neumeier

Sound experimental ingots of zinc alloys for use as rolling slabs were cast with a specially constructed, semicontinuous casting machine. Nominal alloy compositions of Zn-1.0 percent Cu, Zn-0.12 and 0.36 percent Ti, and Zn-1.0 percent Cu-0.03 to 0.36 percent Ti were cast. This Bureau of Mines study was conducted to evaluate the suitability of the casting procedure for providing stock for rolling into sheet. Microscopic examination of ingot sections revealed structures in which grain size varied from the outer to center ingot zones. Columnar grains present in the center zone of the Zn-1.0 percent Cu ingot were absent in the titanium-containing ingots. The ingots with titanium displayed a finer grain size and eutectic structure in the center ingot zone than in the outer zone; the transition in grain size between the two zones was quite abrupt in some ingots. The overall grain size of the titanium-containing ingots was finer than that of alloys cast by more conventional methods. Chemical analysis revealed that compositional segregation is not a significant factor in the formation of the ingot structure. Microstructural studies of small ingots of similar alloys solidified at slow, fast, and intermediate rates confirmed that the ingot structure in the semicontinuous-cast ingots is related to cooling rate, which is, in turn, related to the particular casting machine design and the influx of cooling water on the withdrawing ingots. Microstructures of thin sheet hot-rolled from slabs of the semicontinuous-cast ingots demonstrated that the ingot structure does not preclude the rolling of sheet having a uniform microstructure. Results of hardness surveys of the semicontinuous-cast ingots demonstrated that copper and titanium exert essentially additive hardening effects in these cast alloys.

Jan 1, 1968

By Graham W. Marks

The general positions of the absorption maxima of aqueous solutions of the violet and green isomers of chromic sulfate the visible spectral region have long been known, but, to the knowledge of the writer, no comprehensive studies have ever been made. To gain further knowledge concerning these inorganic complexes and to investigate the possibilities of developing an analytical method for determining the concentrations of the violet and green isomers in a mixture, a more complete investigation was made in the spectral range from 325 to 850 millimicrons.

Jan 1, 1951

By B. Numerov

A numerical proceeding of corrections with respect to topography is worked out for places near the station and a graphical one for the remote parts of the terrain. The description is clear and very detailed. The numerical proceeding is very similar to that of the Eötvös and Schweydar methods which are in use already. In both methods the levelling is accomplished in certain circles and fixed azimuths around the station. While, in using the Eötvös method, the height differences are directly inserted into the final formulas with regard to the foot of the instrument and in case of accurate formulas derived by Schweydar the height differences are calculated with respect to the center of gravity of the attachment, Numerov introduces functions A and B, the heights, of the terrain and of the center of gravity, which are to be inserted into the formulas.

Jan 1, 1929

By Spencee L. Willett

In 1986, at the request of the Bureau of Land Management, the U.S. Bureau of Mines studied a 51, 160-acre portion of the 107,920-acre Diablo Mountain Wilderness Study Area (OR-001-058) in order to evaluate its mineral resources. The study area is located 1n Lake County, OR, about 45 miles northwest from Lakeview. The study area is located near the northwest corner of the Basin and Range physiographic province. Tertiary Picture Rock basalt with tuff interbeds underlies the area (Travis, 1983). No mineral resources were identified; no mines, prospects, claims, or mineralized areas exist in or adjacent to the Diablo Mountain study area.

Jan 1, 1987

By Floyd R. Anderson

Noise control of existing pneumatic drills is difficult and runs into cost, performance and weight penalties. A need exists for a start-from-scratch approach for quiet pneumatic rock drills. The designs based on Leavell Principles which has been successfully used in demonstrating a quiet and vibration free paving breaker, is the concept chosen here. This report shows the feasibility of a quiet stoper for drilling roof bolt holes in coal mines. The work is directly applicable to pneumatic percussive rock drills. The report shows an oscillator based on patented Leavell concepts which results in a vibration free tool and noiseless exhaust. Dynamics of the oscilator is analyzed. Independant rotation of drill rod is provided by an air motor (screw expander) and flushing of cuttings is accomplished by an air ejector in a compact lower housing. The feasibility of no exhaust noise, low drill machine noise, and vibration free casing is discussed.

Jan 1, 1977

By R. M. Jimeson

Pressure-drop measurements through beds of granular iron, lathe turnings, steel wool, and parallel-plate assemblies were made at linear velocity and gas-density ranges expected in the Fischer-Tropsch hot gas recycle process.4/ Equations relating pressure drop, linear velocity, gas density, and bed porosity were derived. The results indicate that the exothermic heat of reaction can be removed at a lower cost by using catalyst beds with high porosity. INTRODUCTION The Fischer-Tropsch hot-gas-recycle process requires a catalyst offering low resistance to gas flow as one condition to economic feasibility. Conventional granular or spherical catalysts used during early development of the process in Germany did not meet this requirement. Large pressure drops across these beds made the cost of recirculating the gas excessive. The Federal Bureau of Mines is investigating the process by using novel and unusual catalysts that offer little resistance to gas flow. Pressure-drop measurements across these types of catalyst beds are discussed in this report.

Jan 1, 1959

By Oliver Bowles

The wire saw, introduced by the Bureau of Mines about two years ago, has revolutionized slate quarrying in Pennsylvania. The success of the saw since its early accomplishments has become greater and greater as the equipment has been perfected and skill acquired .in its use. In the first test made, a cutting rate of 9.7 square feet per hour was attained; in the next four cuts, made early in 1927, the average rate of cutting was increased to 12.8 square feet per hour; in 1928 a maximum of 34 square feet per hour had been attained, with a general average of about 20 to 25 square feet, The wire saw is now regarded as essential equipment in practically all of the quarries in the Bangor, Pen Argyl, and Windgap districts. The wire saw consists of a three-strand steel cable of 3/16 or 1/4 inch diameter running as an endless belt. The driving pulley is a 40-inch double-groove cast-iron sheave. A tension pulley supported by a frame mounted on wheels may travel back and forth on a short track. A weight of 800 to 2,000 pounds gives the desired tension on the wire. The driving units consist of electric motors with direct-drive compactly enclosed gear reduction, or double-belt speed-reduction units; the former is preferred. Silent chain and. pinion gear reductions are used to a limited extent. The travelling speed of the wire is about 15 feet per second. The driving and tension equipment are shown in Figure 1, A.

Jan 1, 1929

By William C. McBee

Specialized sulfur concretes were developed by the Federal Bureau of Mines as a result of research for the beneficial utilization of sulfur in construction materials. Materials were developed for use in acid and salt corrosive environments where portland cement concrete has been found to deteriorate. Because the mineral aggregates also come into contact with the corrosive media, concretes were developed utilizing both limestone and quartz aggregates. The sulfur binder used with both aggregates was modified by reaction with 5 pct dicyclopentadiene to improve product durability. Sulfur quartz aggregate concrete was found to have moderately high strength characteristics (6,000 psi compressive) and was extremely resistant to chemical attack by both acid and salt solutions. Sulfur limestone aggregate concrete exhibited very high strength characteristics (9,000 psi compressive) and was extremely resistant to chemical attack of salt solutions. Both types of concretes maintained their strength and integrity after long-term testing in acid and salt solutions and exhibited considerable resistance to damage by the action of freezing and thawing. Potential uses include leach tanks, electrolytic cells, thickeners, bridge decking, industrial flooring, pipe, and tile.

Jan 1, 1979

By W. M. Dressel

The Federal Bureau of Mines has obtained data by differential thermal analysis of the various minerals that represent the nation's resources in manganese. These data are supported by X-ray diffraction analysis, chemical analysis, mineralography, and optical mineralogy, and provide fundamental information on the response of each mineral to thermal treatment in oxidizing, reducing, and neutral atmospheres. The information can be applied advantage¬ously in the identification of manganese minerals. Its greatest potential value, however, lies in the application of the quantitative data on the reaction temperatures, rates, and products to the more efficient extraction of manganese from U.S. ores. Thermal analysis curves are presented for certain manganese minerals, namely hausmannite, bixbyite, braunite, pyrolusite, lithiophorite, cryptomelane, hollandite, manganite, rhodochrosite, and rhodonite. The original minerals and the products of their thermal decomposition were identified by X-ray diffraction analysis, supplemented by chemical analysis and mineralogical identification.

Jan 1, 1961

By Charles W. Huggins

To determine the nahcolite and dawsonite content in oil shales, the Bureau of Mines compared X-ray diffraction, infrared spectroscopy, thermal methods, and a previously published method by Smith and Young based on the selective solubility of sodium compounds. The Smith and Young method and a new method based on the weight of carbon dioxide produced by thermal decomposition are recommended for determining nahcolite. X-ray diffraction and the Smith and Young method are recommended for determining dawsonite. X-ray diffraction, infrared spectroscopy, and differential thermal analysis were useful for identifying other minerals in the samples.

Jan 1, 1973

By C. C. Hwang

The Bureau of Mines formulated a method for calculating the concentration of entrained dust from a dust deposit by a turbulent gas stream. In particular, a diffusion equation is used to calculate dust concentrations in a channel following an explosion. Dust leaving the channel walls was treated as originating from stationary or moving, and single or multiple material sources. Formulas and sample computations for various types of dust sources in circular and rectangular channels are given, based on experimental entrainment rates. The analysis predicts the dust concentration as a function of time and channel space. The results appear to agree with the physical characteristics of explosion-driven dust dispersion in a O.6-m-diameter, 50-m-long explosion tunnel. The analysis is also applied to simultaneous and consecutive dispersion of coal and rock dust from simulated coal mine surfaces (walls, floor, roof, and ribs).

Jan 1, 1974

By E. W. Dean

A previous report of the Bureau of Mines* has supplied data for the physical and chemical properties of samples of crude petroleum produced in the eastern fields of the United States. It was issued as a preliminary chapter of a bulletin which is to cover the results of a survey of the entire country. The present report is a second preliminary chapter including figures that are available for the producing fields of the Rocky Mountain district. Work is being continued. with a series of samples from the States of Kansas and Oklahoma which will be described in a third preliminary chapter, to appear at a subsequent date. Acknowledgments. The obtaining of samples was rendered possible through the courtesy of representatives of a number of producing and refining companies operating in the Rocky Mountain district. The Bureau hereby acknowledges its appreciation of the hearty spirit of cooperation that was universally encountered.

Jan 1, 1921