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By James V. Kelly

During the spring and summer of 1947, the Bureau of Mines conducted an investigation and core-drilling program in the vicinity of the Rodham mine, approximately 4 miles north of Shullsburg, Wis. This work was undertaken as a part of a general study of the zinc and lead-producing area of southwestern Wisconsin. Work in the Rodham-mine area was done to investigate further a mineralized area frilled in part by the Puritan Exploration Co., a Delaware corporation, with offices in Galena, Ill. Some significant lead-bearing samples were obtained, but no continuous ore body was disclosed as a result of the Bureau of Mines work.

Jan 1, 1949

By Richard C. Repsher

Intermittent mining in the slope section at Dutch Creek No. 1 mine, Carbondale, Colo., of the Mid-Continent Coal and Coke Co. has resulted in erratic and minimal rock noise data, which, in turn, has necessitated a change in the method used to plot daily mine noise in order to be useful to the researchers at the mine. Daily and weekly cumulative plots of rock noise under these conditions have not shown significant stress changes as clearly as bimonthly or longer noise rate plots. Hence, longer term cumulative rock noise plots, as described in this Bureau of Mines report, have been added to the data analysis at Dutch Creek No. 1 mine, and have been shown to delineate unique areas of rock noise activity more clearly than shorter term plots. The longer term plots should aid in the detection and delineation of potential failure areas, when used in conjunction with other proven forms of data analysis.

Jan 1, 1979

By Philip E. Sanker

The Bureau of Mines conducted small-scale batch and semicontinuous tests on the reduction of zinc sulfide with iron according to the reaction ZnS + Fe ? FeS + Zn to determine reaction kinetics in the temperature range 1,000° to 1,400° C and to investigate the potential use of a scrap iron reductant. Batch tests indicated that a temperature of at least 1,300° C with a 1:1 mole ratio of Fe to ZnS is needed for good zinc recovery. Semicontinuous tests were conducted, using four zinc concentrate samples, containing various percentages of copper, cadmium, and lead, which were reacted with iron and iron contaminated with iron oxide and tin in an externally heated graphite furnace. Analysis of the zinc metal and FeS matte reaction products showed cadmium to be entirely in the zinc metal, copper to be in the FeS matte, and lead to be about 60 pct in the zinc metal and 40 pct in the matte. Tin reported to the matte, and none was detected above the O.OS-pct level in the zinc. Sulfur dioxide was not detected in the offgas when up to 20 pct of the iron was replaced by Fe203.

Jan 1, 1976

By A. J. Kraemer

The Bureau of Mines for a number of years has been carrying on an investigation of properties of crude oils from producing fields in the United States and has published a series of reports on different fields, including oil fields of Texas3. Production Data The Spindletop field was discovered in 1901 when the pay sand was found at deaths of about 800 feet. During the following twenty-five years a number of attempts were made to find a deep productive sand. All attempts sere failures until a roll drilled by the Yount Lee Oil Company found oil late in 1925. An intensive drilling campaign began at once, and the production of the Spindletop field increased to a daily average of 93,217 barrels in September, 1926; the present production is estimated at 66,000 barrels doily. Tile following table taken from the Oil and Gas Journal for February 10, 1927, shows the daily average and the total production by ninths for 1926.

Jan 1, 1927

By Arthur J. Hudson, Lawrence W. Scott

The performance of RETIMET metal foam as a flame arrester on explosion-proof enclosures was investigated by the U.S. Bureau of Mines both in laboratory tests and at the U.S. Mine Safety and Health Administration's (MSHA's) Approval and Certification Center, Triadelphia, WV. The objective of this research was to develop a permissible pressure vent for use on lightweight, vented, explosion- proof enclosures. In laboratory tests, four grades of RETIMET, a stainless steel foam material, were evaluated: (1) 45 NC-7, (2) 45 NC-13, (3) 80 NC-7, and (4) 80 NC-13. Explosive gas mixtures were prepared by a dynamic flow system. Ignition was by a low-voltage arc. Each grade of RETIMET metal foam successfully arrested the flame front in all methane-air tests. To evaluate RETIMET metal foam on large, commercial size enclosures, a multicompartmented enclosure was designed and tested in MSHA's explosion gallery in Triadelphia, WV. Extensive explosion testing revealed that a minimum vent-area-to-enclosure-volume ratio of 11.33 in2/ft3 is required to keep internal pressure rises below 3 psig. The RETIMET metal foam functioned satisfactorily in all tests as evidenced by the absence of external ignitions.

Jan 1, 1992

By J. E. Hamak

This publication contains analyses and related source data for 144 natural gas samples from 19 States. Of the total samples, 139 were collected during calendar year 1990. The remainder were collected earlier, but releases granting permission to publish were not received until 1990. 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 were made by mass spectrometer and chromatograph.

Jan 1, 1991

1. In 2001, a total of 7,131 sand and gravel mining operations reported employment statistics to the Mine Safety and Health Administration (MSHA). Sand and gravel mines comprised 48.8% of all mining operations, the largest percentage of all mining sectors. Sand and gravel mines are distributed throughout all 50 states. The median number of operator employees per sand and gravel mine was 3.0.

Jul 1, 2003

By B. J. Scheiner

The Federal Bureau of Mines investigated an electrolytic oxidation procedure for extracting lead, zinc, copper, and silver from lead-zinc concentrates. Concentrates slurried in brine were pumped through the anode compartment of electrolytic cells equipped with selective ion diaphragms. Hydrochloric and hypochlorous acids generated in the anode compartment converted the metal sulfides in the concentrates to soluble metal chlorides, sulfate ion, and elemental sulfur. Metal extractions of 92 to 100 pct were obtained from lead-zinc concentrates at an energy consumption ranging from 1.5 to 5.0 kW-hr/lb metal extracted. Sodium hydroxide was formed in the cathode compartment at a current efficiency of >99 pet. Silver and copper were extracted from refractory tetrahedrite minerals, but the process entailed a relatively high energy consumption. Sealing the top of the diaphragm cell utilized the chlorine more effectively, thereby reducing energy consumption 10 to 50 pct.

Jan 1, 1975

By D. G. Foot

The Bureau of Mines devised a direct flotation method for recovering potash from carnallite (KC1?MgC12?6H20) ore characterized by a high content of water-insoluble impurities. The method includes (1) a decomposition leach of the carnallite, (2) flocculation-depression of the insoluble slimes, (3) potash rougher, cleaner, and recleaner flotation, and (4) final product leaching. The technique eliminates the necessity for removing the water-insoluble slimes by mechanical or flotation de-sliming. Laboratory results demonstrated that the direct flotation procedure, when compared with conventional techniques, yielded equivalent or improved flotation results with equal or less reagent consumption. Locked-cycle testing of the direct flotation method recovered 87.8 pct of the potassium in the flotation feed in a final product containing 60.6 pct K20. A flowsheet incorporating the carnallite leaching-potash flotation procedure is presented.

Jan 1, 1982

By R. V. Subramanian

This project financed by the Bureau of Mines investigated the use of polymers to achieve rock bonding and reinforce coal mine structures for better or permanent ground support. Support was achieved by pumping the polymers into the rock interstices to bond the mass together for increased structural competence. Holes were drilled in the mine roof, after which the polymers were injected at about 100 psi to permeate the cracks. Initial laboratory work indicated that of all the resin systems tested, the epoxy resins could most likely be modified to be suitable for rock injection. This was confirmed when several potentially suitable resin systems underwent intensive evaluation. In a series of three field tests, two conducted in a copper mine with coal mine-type shale and the third in a coal mine, it was shown that the polymers penetrated cracks less than 0.005 inch wide. The fast-setting epoxy systems, cured out in thin films under mine conditions, produced a bond exceeding the strength of the uncracked virgin rock.

Jan 1, 1974

By J. A. McAllister, H. G. Iverson, K. C. Dean

"INTRODUCTION During the course of the investigation of the occurrence of manganese deposits in the western United States, laboratory studies of concentration were conducted at the Salt Lake City station on a sample of ore from the Lake Valley mines of the Newalpitt Fluorspar Corp. of Deming, N. Mex. The ore was reported to be representative of the type that would be mined for mill feed. The sample tested was found to be amenable to beneficiation by ore-dressing methods for the production of products that, when sintered, assayed over 44 percent Mn.At the beginning of the investigation of manganese-ore beneficiation in December 1940, the only product marketable to Metals Reserve Company was ferrograde manganese grade B, the requirements for which follow: Mn, min., 48 percent; Fe, max., 7 percent; Si02, max., 10 percent; P, max., 0.18 percent; Al203, max., 6 percent; Zn, max., 1 percent, Al2O3,Later the specifications were modified gradually. As of May 15, 1943, manganese products were acceptable if they contained over 35 percent manganese and less than 3 percent zinc and 1 percent phosphorus. Prices were based upon material containing 48 percent manganese, 6.0 percent iron, and 11 percent silica plus alumina. Premiums were paid for manganese content in excess of 48 percent and iron content below 6 percent, penalties being imposed upon products containing less than 43 percent -manganese, or more than 6 percent iron, or more than 11 percent silica plus alumina. The specifications for commercial manganese further required that maximum particle size be 12 inches and that, 75 percent of the product be coarser than 20-mesh. Therefore, fine material such as table and flotation concentrates had to be nodulized or sintered. In addition, oarbcnate manganese ores were not acceptable unless calcined."

Feb 1, 1948

By W. A. McKinney

A sample of oxidized copper ore from a large deposit located in Pinal County, Ariz., about 50 miles northeast of Tucson, was treated by the Federal Bureau of Mines in a small-scale continuous pilot plant by a procedure which comprised acid curing complemented by water leaching and countercurrent decantation washing in a series of drag classifiers. A feed was prepared by pugging minus 1/4-in, ore with concentrated sulfuric acid and about 10 pct, of eater, followed by curing in batches for about 24 hr. The cured ore was fed continuously to a leach drum, where it was mixed with advance solution from the countercurrent washing system to dissolve the sulfated copper. The pulp was thickened and washed in four Esperanza-type classifiers, using a flocculating agent to obtain rapid settling and thickening. The leached ore pulps thickened satisfactorily in the drag classifiers when about 0.8 lb. of a polyacrylamide flocculant per ton of dry feed was used. Clear overflow liquors were obtained, and classifier rake products containing about 60 pct. solids were produced, As much as 90 lb./hr. of ore was treated in the plant, with a recovery of 60 pct. of the total copper or 80 pct, of the acid-soluble copper when 2 tons of water per ton of feed was used in washing. The acid consumption was 4.3 lb./lb. of copper recovered. On the basis of the maximum feed rate employed and the effective pulp-settling area of the classifiers, a total of 1 sq. ft. of pool area was required per ton of dry feed per day for the thickening and washing operations. The washing efficiency in the test was 95 pct.

Jan 1, 1960

By L. E. Schultze

[The Bureau of Mines conducted bench-scale studies to develop techniques for stripping tetravalent cerium from tri-n-butyl phosphate solutions. Experiments were conducted in a constant-temperature bath using beakers and mechanical stirring. Ninety-five pct of the cerium was stripped from a 50-pct tri-n-butyl phosphate 50-pct kerosene solution containing 0.18 M cerium in 15 minutes at 50° C using 0.11 M aqueous formaldehyde.]

Jan 1, 1974

By E. L. Rawlins

Pipe lines through which natural gas is flowing should be buried in order to minimize fluctuations in the temperature of the gas, as these fluctuations have several harmful effects. One of these effects is to decrease the accuracy of measurements of gas volume. In order to meter properly the quantity of gas flowing past any point in a transmission system, it is necessary to how the temperature of the gas. If the temperature remains fairly constant, the gas flow can be measured with a close degree of accuracy, but if it fluctuates rapidly, close measurement is impossible.

Jan 1, 1926

By G. W. Birge

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. The selection of coal beds in Westmoreland County for coking tests was based, in part, on estimates of the coal reserves by Dowd,3/ who estimated the recoverable reserves in beds 28 inches or more thick, in thousands of tons, as follows: [ ]

Jan 1, 1957

By L. B. Pankratz

High-temperature heat-content values of gallium and scandium sesquioxides were measured over the temperature range from 298° to 1,800° K. The results fill gaps in the thermodynamic information for these compounds; no previous similar data existed. The heat-content values were combined with heats and entropies of formation to obtain free energies of formation of gallium and scandium sesquioxides to 2,000° K. The thermodynamic stabilities of the sesquioxides of aluminum, gallium, scandim, and yttrium were compared.

Jan 1, 1963

By J. Douglas Causey

In 1985, at the request of the Bureau of Land Management, the U.S. Bureau of Mines studied a portion of the 110,000 acre Massacre Rim Wilderness Study Area (CA-020-1013). The area studied, containing 23,260 acres, is located in northwest Washoe County, Nevada, about 25 miles west of Vya adjoining the Charles Sheldon National Wildlife Refuge. Basalt caps older tuffaceous sedimentary rocks in an area that contains no claims or prospects. No mineral resources were identified during this investigation.

Jan 1, 1987

By M. Howard Berliner

During the spring of 1944, the Bureau of Mines investigated the Crescent mine area near the village of Rewey, Iowa County, Wis., as part of a general investigation of the zinc-producing area of southwestern Wisconsin. The work was done when every effort was being made to increase the production of metals important to the Nation's war program. The Bureau of Mines completed 24 churn-drill holes in an area immediately to the west of a mineralized section which had been mined through shallow workings for lead and zinc more than 40 years earlier.

Jan 1, 1948

By Foster Fraas

The response of minerals in magnetic separators is in accordance to dynamic rather than static magnetic susceptibility values . The dynamic value varies with respect to both passage speed through the separating field and time of exposure in a preliminary treatment field . Tests on 16 minerals and solids have demonstrated that both of these factors affect different minerals in different ways .

Jan 1, 1964

By R. V. Ramani, R. A. Jankowski, R. Bhaskar

"The spatial distribution of airborne dusts, deposition of dust in the airway, as well as the effect of airflow velocity and particle density on dust behavior in mine airways were studied in a set of experiments performed in a mine airway under controlled conditions. Considerable deposition of dust near the source was indicated. Pronounced effects due to velocity were observed in ambient dust concentration and deposition along the mine airway, both in the respirable and the total size ranges. Cross-sectional concentration measurements indicate an increase in concentration from the roof to the floor. The average cross-sectional concentration is about 75% of the concentration in the center of the airway.IntroductionA number of studies have been performed since the early 1950s on the behavior of dust in mine air (Bradshaw and Godbert, 1954; Dawes and Slack, 1954; Bradshaw et al., 1954; Hall, 1955-56; Reinhardt, 1971; Ford, 1971; Courtney et al., 1982). While the experimental data available from these studies are indeed useful in understanding dust cloud behavior in a specific situation, no generalized conclusions can be drawn because of the lack of data on parameters such as flow velocity, size distribution of the source dust, and particle density. These change from mine to mine or even within the same mine. The present study is aimed at providing a better understanding of the temporal and spatial behavior of dust particles in underground' mine airways (National Academy of Sciences, 1980). The characteristics studied encompassed airborne concentrations and floor depositions over the entire size range as well as the respirable size range. The experimental results in this paper are intended to complement a mathematical model developed to predict ambient concentration and deposition of airborne dust in mine airways (Bhaskar and Ramani, 1986)."

Aug 31, 1989