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By Harry V. Makar

As part of a continuing research program for conserving domestic mineral resources, the Bureau of Mines is investigating new and improved scrap identification techniques to improve sorted mixed scrap purity. This report focuses on various classes of wrought and cast copper alloys produced with recycled scrap. Based on a survey of the literature, principal alloys, such as the brasses and bronzes, are examined with respect to impurity elements and their effects on metallurgical behavior. Effects of elements such as lead, antimony, iron, chromium, and aluminum are discussed. The metallurgical effects described include hot shortness, fire cracking, and undesirable phase transformations.

Jan 1, 1985

By F. L. Wideman

This paper lists resources of sulfur in Wyoming, Colorado, Utah, New Mexico, and Arizons, an area comprising approximately 522,600 square miles, Sources of sulfur occuring within the region are sulfur are, pyrite and pyritic ores, and natural gases and petroleum. Data concerning these sources are presented on a statewide basis. Some of the known deposits of sulfur ore are surficial and of fumerole origin; other deposits have resulted from oxidation of pyrite or sulfide ores of copper, lead, and zinc. The deposits are small and the sulfur is distributed erratically in them. There is a small production from some of the deposits, and the material produced is used as soil conditioner.

Jan 1, 1957

By R. Barany

The heats of formation at 298.15° K of calcium tungstate, calcium molybdate, and magnesium molybdate were determined by solution calorimetry. For the heats of formation from the elements, the values obtained were calcium tungstate, -402.4 ± 0.5 kcal/mole, calcium molybdate, -369.5 ± 0.3 kcal/mole, -334.8 ± 0.2 kcal/mole. For the heats of formation from the oxides J the values obtained were calcium tungstate, -49.2 ± 0.4 kcal/mole, calcium molybdate, -39.6 ± 0.1 kcal/mole, and magnesium molybdate, -12.9 [ ] 0.1 kcal/mole.

Jan 1, 1962

By Daryl R. Tweeton

The Bureau of Mines conducted experiments to measure the influence of environment on the friction and wear of a steel-quartz system at several speeds and loads. In each test a quartz block was pressed against a rotating ring of low-carbon steel. Environments used were moist air, dry air, dry nitrogen, water, aqueous oleylarnmonium acetate (ClsH35NH3+-OCOCH3), and aqueous aluminum chloride (A1C13). The sliding speeds were 2.2, 13, and 33, cm/sec, and the loads were 6.8 and 13.6 kg. The coefficient of friction, the wear, and the roughness of the surfaces were measured, and the wear debris was examined. The coefficient of friction was significantly lower in moist air at 2.2 cm/sec than for any other combination of environment and speed employed, and was generally an inverse function of the oxidizing ability of the environment. The coefficient of friction increased somewhat with increasing load. The wear of the steel rings was greatest in dry air at all speeds and loads. The wear of the quartz blocks at 180 rpm was greatest in dry air, but at 12 rpm it was greatest in nitrogen. Friction and wear in aqueous oleylarnmonium acetate and in aqueous aluminum chloride were similar to effect in water alone.

Jan 1, 1976

By Roy T. Sorensen

The Bureau of Mines has investigated the recovery of cell-grade alu-mina by RCI leaching of calcined kaolin in the alumina miniplant at its Boulder City (NV) Engineering Laboratory. Classification and thickening were used for separating aluminum chloride leach liquor from the siliceous residue generated in the acid leaching step of the clay-HCI process. Coarse solids were classified from fines at 115 mesh and countercurrently washed in three additional spiral classifiers. Fines were treated in a conventional five-thickener, countercurrent decantation circuit. When this method was applied to the solids-liquid separation of slurry from RCI leaching of minus lO-mesh calcined kaolin, 75 pct of the residue reported as classifier sands and 25 pct as thickener underflow. Predicted individual classifier and thickener area requirements were 6 and 25 ft2/tpd, respectively. Total thickener circuit flocculant requirement was 2.4 lb/ton solids. Aluminum chloride pregnant liquor was produced that analyzed 8.4 pct A1203 and contained more than 97 pct of the alumina in the liquid phase of the slurry. Bench-scale settling tests were used to correlate fines content of leach residue to thickener area and flocculant requirements.

Jan 1, 1983

By GEORGE T. Harley, Walter R. Storms

This paper, which describes mining mothods at International Minerals & Chemical Corp, 'e. potash mine. in. Eddy. County, N. Mex., is one of a sories being prepared by the Mining Branch of the Bureau of Minos. on mining method a and practicos in, various mining districts of the United States. The mine shafts and. surface plant or International Minerals & Chemical Corp. are situated. in. sec.. 12, T. 22 S., R. 29 E., N. M. P. M., about 26-1/2 miles by paved highway east of the city of Carlsbad (figs. 1, 2, and 3). A spur line of the Atchison, Topeka & Santa Fe Railroad connects the mine with the Clovia-Pecos branch of the same road near Loving, a few miles south of Carlsbad. This spur also serves the refinery of United Staics Potash Co. This report gives. the history and describes the geology of the district. Methods of prospecting, exploration, sampling, and estimation of tonnage and values are explained; development and mining methods are discussed in con- siderable detail; transportation, ventilation and drainage are outlined; safety measures are noted; and the wage scale and organization are mentioned.

Jun 1, 1949

By J. E. Tiffany

Some of the gases produced by permissible explosives on detonation are poisonous, and the probable hazard involved by the inhalation of carbon monoxide in the past has been evaluated from results of tests in the Bichel Gage. Tests have now been made in the Experimental Coal Mine of the Bureau of Mines at Bruceton, Pa., to determine the composition of the gases obtained under actual mining conditions for the purpose of comparing these, results with those found by the Bichel gage tests. Two permissible explosives were procured for these tests, one that produces a relatively low quantity of poisonous gases in the Bichel gage (24.8 liters per 1-1/2 pounds of explosive) and another that produces a relatively high quantity of poisonous gases (94.6 liters per 1-1/2 pounds). The first of these is designated by the Bureau of Mines as a class A4/ explosive and the other is designated a class B explosive. In comparison with Bichel-gage tests, the shooting of permissible explosives in a coal shot hole resulted in a large reduction in the quantity of carbon monoxide, the principal poisonous gas, which; in the mine tests, was only 22 percent of that found in Bichel-gage tests: The quantity of carbon monoxide from the class B explosive in Bichel-gage tests was 3.8 times larger than that from the class A explosive; in the coalmine tests the ratio was 4:1. The concentrations of carbon monoxide in the mine tests, as determined by analysis of the atmosphere in an enclosed space resulting from shooting 1-1/2-pound and 3-pound charges of the class A explosive, were 0.03 and 0.06 percent, respectively, and the concentrations from 1-1/2-pound and 3-pound charges of the class B explosive were 0.10 and 0.24 percent.

Jan 1, 1950

By F. S. Wartman

Recent changes in metallurgical practice, particularly those in flotation, have altered greatly the functions of the different units of a copper smelter. Gangue minerals are removed from the feed so much more thoroughly that the reverberatory furnace, once virtually a concentrator in which a low-grade ore was concentrated into a rich matte by virtue of the removal of gangue elements as slag, has become very largely a melting furnace in which the rich flotation concentrates are rendered molten so that they may be converted. Moreover, since the proportion of matte to slag in the reverberatory furnace output is greater than it was formerly, the amount of converter slag returned to the reverberatory for cleaning is, in comparison to the amount of slag actually formed in that furnace, also much larger. In some cases, approximately half of the reverberatory dump slag may have originated in the converter. The increase in the proportion of convertor slag to total slag produced has brought about certain consequences not entirely desirable. Converter slags contain a high percentage of iron and therefore are high in specific gravity and are very basic. A considerable guantity of magnetite, both dissolved and suspended as solid crystals, is always a component, The basic nature of the ordinary converter slag and the presence of the suspended magnetite crystals make impossible the reduction of the copper content of the slag below approximately 1 per cent by even the most prelonged settling, and a re-treating process is necessary. At present, general practice in western copper smelters is to return the converter slag molten to the reverberatory furnace. Here dilution by mixing, with slag formed in the reverberatory furnace and reaction with raw sulphides and siliceous materials in the reverberatory feed reduce the magnetite and increase the silicates to the point necessary for a satisfactory dump slag.

Jan 1, 1930

By C. J. Walker

The Bureau of Mines undertook a theoretical and laboratory study to determine the feasibility of using ethylene as a tracer for natural gas in underground gas-storage reservoirs. The study indicated that ethylene was a useful gas tracer in underground gas storages. Tracer losses were not excessive. Laboratory tests were conducted at pressures as high as 500 psia in both wet and dry consolidated-sandstone cores, evaluating tracer loss with gas blends containing natural gas with different concentrations of ethylene tracer. Under certain conditions losses were less than 17 percent.

Jan 1, 1966

By Robert J. Hundhausen

During the early part of World War II , it appeared likely that supplies of chromite for United States industry might become critically short . As a part of the ensuing search for new sources of domestic chromite supply , the chromite - bearing black sands along the coast of southern Oregon were hurriedly investigated by State and federal agencies and by private interests , These investigations led to a decision to begin exploitation of the deposits immediately . A government stock- piling program was put into effect , a concentrator was financed by the Defense Plant Corporation , two privately controlled companies were encouraged to start mining operations , and the Bureau of Mines and the Geological Survey were authorized to search. for additional reserves of minable ore .

Feb 1, 1947

By R. L. Hopkins, H. T. Rall, H. J. Coleman, C. J. Thompson

Two methods were tested for separating sulfur compounds in certain petroleum fractions into types . Such separation is preliminary to identifying the compounds . Each method involved extraction of sulfides from petroleum sulfur concentrates . In the first method , the sulfur concentrate was reacted with methyl - ptoluenesulfonate to form sulfonium compounds from which unreacted portions of the sample were removed by washing with solvent . The sulfides then were recovered by heating the sulfonium compounds with anhydrous triethanolamine . The second method consisted of passing anhydrous hydrogen iodide into a n-butane solution of the sample cooled in dry ice , whereupon the hydrogen iodide adducted with the sulfides to form sulfonium compounds . These adducts separated as crystalline solids or , more frequently , as glassy viscous liquids . The sulfide was regenerated by adding water to the filtered sulfonium compound and was recovered by steam distillation or by extraction with pentane . These methods have been evaluated , using individual pure sulfur compounds and blends of sulfur compounds . They also have been applied successfully to separating sulfides from sulfur concentrates derived from petroleum fractions .

Jan 1, 1964

By Michael J. Friedel

As part of an investigation aimed at improving the health and safety and competitiveness of the mining industry, the U.S. Bureau of Mines evaluated the application of common offset radar profiling, using a 250-MHz ground-penetrating radar (GPR) system, for the detection of fractures in igneous rock. A series of radar reflection surveys were conducted to detect and delineate the extent of fracturing at various granodiorite and gabbro quarries and outcrops located in Minnesota. The application of radar profiling for detecting joints, sheeting fractures, shear zones, and depth to water table was demonstrated to be feasible with minimal processing. Radar reflection interpretations were verified by visual inspection of the rock mass and field mapping of local structure. The radar reflection section provides a simple, rapid, and cost-effective means for mapping of shallow (less than 10 m) small-scale fractures (greater than 0.25 cm) in igneous rock masses (characteristic of velocities between 0.061 m/ns for gabbro and 0.125 m/ns for granodiorite). Depth or distance estimates to fractures are within 10 pct of the actual, and time-shift compensation is necessary only when topographic irregularities exceed 30 cm.

Jan 1, 2010

By G. L. Oldright, Virgil Miller

"ACKN0WLEDGMENTSThe data given in this paper were collected at the Bunker Hill smelter through the courtesy of Stanley A. Easton, the vice-president and general manager, Frank M. Smith, the smelter director, and with the assistance and cooperation of A. F. Beasley, the smelter superintendent, and his staff members.THE BLAST FURNACE AND PLANTThe general lay-out of the recently built (1917) Bunker Hill plant has been given in the technical press in articles that were cited in Report of Investigations 3088. In addition it may be noted that the description of an ideal smelter given by Riddell 5 a year later fits the Bunker Hill smelter very well, with some changes, such as the location of the stack, made necessary by topography. For purposes of this article on the blast furnace it may suffice to state that the plant is one of the ""side hill location"" type. The various successively lower benches may roughly be considered as made for (1) the stack, (2) Cottrells and bag houses, (3) Dwight and Lloyd sintering machines with the equipment or bins for handling or mixing the feed and storing the finished product, sinter, and (4) the blast furnace feed floor with a slightly rising gradient to the bottom of the bins for sinter, feed, and take. The lowest bench (5) might be considered that of the blast furnace tapping floor at which or at appropriately slightly lower elevations are located the units for softening, refining, and treating precious metals, and for casting and loading lead. A very careful study of grades was made in order to be able to handle the products easily. All units were left with at least one end open to permit expansion of the plant, it desired, and each unit was separated from the other, evidently so that the operators on one level would be annoyed as little as posssible with the products made on another."

Apr 1, 1931

By Jr. Herty

As the problem of inclusions in steel has become increasingly important, more and more attention has been paid to the source of the oxide inclusions in steel. In killed steels the oxide inclusions are traceable to the reaction of deoxidizers with the iron oxide dissolved in the steel during the refining period of the open-hearth heat. In a large class of steel known as "rimming steel" the action of the steel during solidification depends entirely on the gas evolved, and this evolution in turn is controlled by the amount of iron oxide in the liquid steel in the mold. It is therefore of great importance to be able to determine the amount of iron oxide dissolved in steel and to devise methods for the control of iron oxide in any class of steel. The object of the present investigation was to obtain a true value of the oxygen con-tent of liquid steel. If the steel has not been deoxidized, the greater percentage of the oxygen is present as iron oxide in solution.

Jan 1, 1932

By Frederick K. Allgaier

This is the first in a series of progress reports on the longwall subsidence research program at the Bureau of Mines Denver Research Center. As part of this program, the Bureau and the Utah Power and Light Co. are cooperating on a study conducted at the Deer Creek Mine, which is directed toward developing the capability to estimate the surface subsidence resulting from longwall mining in a geologic, topographic, and mining environment common to coalfields in the Western United States. A monitoring network has been established at the Deer Creek Mine to measure subsidence over four adjacent longwall panels. To date, two panels have been mined. Subsidence began as the first panel was mined and continued for 1 year following completion of the panel, during which time the adjacent panel was mined" A maximum of 2.7 feet of subsidence occurred over the two longwall panels mined at a depth of 1,500 feet. Because of the length of time that subsidence continued after mining, the final subsidence profiles and angle of draw have not yet been determined.

Jan 1, 1982

By W. G. Pariseau

A U.S. Bureau of Mines case study of pillar recovery in high-grade ore near the Ross shaft at, the Homestake Mine, Lead, SD, has demonstrated the usefulness of the finite-clement method for the evaluation of shaft pillar mining plans and shaft stability. This report, one of three in a series describing the Ross shaft pillar case study, focuses on the premining stability analysis. The two-dimensional computer program UTAH2 was used in advance of pillar mining; results suggested that the shaft would remain stable. Subsequent reports describe parts 2 and 3 of the study. In part 2, borehole extensometers and other instruments were installed to provide data for model verification and shaft monitoring. Results of the recalibrated two-dimensional model confirmed the premining stability evaluation. However, after mining began, great concern developed because of the appearance of cracks and other signs of ground movement over considerable distances from the area of active pillar miping. In part 3, an intense three-dimensional modeling effort using UTAH3 was initiated. The results again showed that the shaft would remain safe. Three-dimensional analyses of alternative pillar mining scenarios indicated that more of the shaft pillar ore reserve could be recovered than previously thought.

Jan 1, 2010

By R. K. Conrad

The Bureau of Mines conducted corrosion research to determine suitable construction materials for geothermal resource recovery plants. Weight loss, pitting and crevice corrosion, U-bend stress corrosion, and electrochemical polarization measurements were made on selected metals in brine and steam process environments produced from high-enthalpy hypersaline brine from geothermal well Magmamax No. 1 at the Salton Sea Known Geothermal Resources Area, Imperial Valley, Calif. Cadmium (and by extension cadmium coatings) and a 6061-T6 aluminum alloy were unsatisfactory because of high general corrosion rates and, in the case of aluminum, severe pitting Molybdenum and niobium (columbium) were resistant to general corrosion, pitting, and crevice corrosion, Copper alloys corroded at rates that may preclude their use in wellhead brine, The presence of iron accelerated the corrosion of the copper alloys Titanium alloys were resistant to general corrosion and stress corrosion cracking in all of the environments. They exhibited crevice corrosion in some of the brine and steam environments and Ti6A14V pitted in the brine environments. They exhibited passive behavior over a broad range of potentials. Exposure tests were conducted on a high-temperature polyphenylene sulfide thermoplastic (Ryton) in the same environments. A 40-pct-graphite fiber-reinforced Ryton composite deteriorated readily in wellhead brine and failed in all of the brine and steam process environments; Ryton coatings on 316L stainless steel were adherent and performed well.

Jan 1, 1983

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Jan 1, 2008

By Arnold B. Hubbard

Automatic control instruments were utilized by the Bureau of Mines for routine assays of large numbers of oil shale samples and other bituminous materials. The standard Fischer assay method was automated by automatically controlling the heating cycles of a battery of 12 electric heaters with electronic controllers and programmers. The condensers were cooled with a modified automatically controlled refrigeration bath. The complete assembly consisted of 12 retort units, necessary control instruments, and the refrigeration bath. This equipment was capable of producing more consistent results than those previously obtained with the gas-heated retorts and of increasing the output of assays substantially with no increase in operating personnel.

Jan 1, 1965

By J. W. Paul

This circular is one of a series of papers4 on coal-mining methods and costs which are being prepared through the sponsorship of the U. S. Bureau of Mines for the purpose of presenting information on present mining methods and certain features which govern costs, safety, and conservation. The methods employed are influenced by natural local conditions with respect to the thickness, character, and dip of the coal bed, the nature of the roof and thickness of the overbearing strata, and the means employed for roof support and its control.

Jan 1, 1929