Search Documents

By Jon C. Volkwein

The Bureau of Mines, Foster-Miller Inc., and Beaver Creek Coal Co. have evaluated the ability of a new system to ventilate a 40-ft-deep cut. A remote-control continuous-mining machine, in a 7-ft-thick seam, with exhausting brattice was fitted with an improved sprayfan system plus additional forward and reverse pointing sprays. Static and dynamic tests using tracer gas were conducted in a full-scale model and under-ground to measure the effectiveness of exhaust face ventilation for various deep-cutting mine and spray configurations. When compared to a lO-ft primary ventilation brattice, the extended-cut spray system consistently provided better face ventilation at all configurations up to and including a 40-ft brattice setback. The system also provided good dust protection and visibility for the machine operator. Another safety advantage is the elimination of the need to set temporary roof supports to maintain the ventilation brattice.

Jan 1, 1985

By ALBERT C. DURHAM

In anthracite mining , pumping is a problem of major importance , and water must be handled and rehandled in almost every mine whether the mine is in operation or idle . The motor - driven centrifugal pump is the most commonly used type of unit for the large pumping installations, and experience has . proved that fully automatic control has certain advantages over manual control . Some of these advantages are greater safety for maintenance personnel , continuous protection against faulty operation , which could cause damage to the Lumping apparatus , and lower pump -room operating costs .

Aug 1, 1948

By H. Dolezal

A laboratory study of acid-ferrous sulfate treatment of low-grade manganese ores from the Cuyuna range, Minnesota resulted in 93-percent extraction of manganese as manganese sulfate with consumption of 3.8 pounds of H2S04 per pound of extracted manganese. Two types of ore were treated in consecutive stages. The first are contained carbonate minerals of manganese and iron, both soluble in H2S04 solution. The second ore contained manganese oxide minerals, insoluble in straight acid solution but soluble in the ferrous sulfate solution obtained from treating the first ore. Leaching data were obtained by countercurrent percolation of coarse (minus-1/2-inch) ore particles at room temperature and by agitating minus-65-mesh ore particles in heated solution. Extraction of manganese and acid consumption were the same, but the percolation leach required 6 days compared with 1 hour for hot agitation. Variations in the size of ore particles treated, leaching time, acid concentration, solution temperatures, and method of applying ferrous sulfate solution to the oxide ore were studied. The effects of several reagents for removing iron from solution and improving filtration were also studied.

Jan 1, 1959

By R. B. McElwaine

From November 1943 to April 1944, the Bureau of Mines put down 18 churn-drill holes aggregating 2,571 feet of bore in an investigation of the virtually abandoned zinc deposits of the north-central Arkansas district, principally in Marion, Boone, Searcy, and Newton Counties. The ore of this area occurs in flat-lying sedimentaries of the Mississippian and Ordovician ages. Much of the zinc is in the form of carbonate and silicate, although some sulfide has been produced. Preliminary studies resulted in selection for investigation of the Big Hurricane mine in northwest Searcy County, the Spies mine in northeast Newton County, and the Coon Hollow mine in eastern Boone County The comparatively large production of th.ese properties in the past was a factor in the selection. This report describes the work accomplished in the investigation and presents the data obtained.

Jan 1, 1948

By J. W. Thompson

MINERALS OWNERSHIP AND POSSESSION. The owner of minerals under a conveyance from the surface owner does not lose his right or his possession by mere nonusage of the minerals. McBeth v. Wetnight (Indiana), 106 Northeastern, 407, p. 410, October, 1914. QUIETING TITLE TO MINERALS-PLEADING. A complaint in an action to quiet title to minerals and to the min- eral rights in certain land is insufficient in the absence of a direct allegation of possession, although it avers that the plaintiff from the time of receiving the conveyance assessed the mineral interest for taxes each year and paid the taxes thereon and exercised various acts of ownership of such mineral interests, in that he caused test pits to be dug on the land for the purpose of exploring the minerals and ascertaining their quality and extent, in going upon the land and looking after them from time to time, and that he accompanied or caused his agents to accompany prospective purchasers of such mineral interests and exhibited the same to such prospective pur- chasers in efforts to sell them. Fowler r. Alabama Iron & Steel Co. (Alabama), 66 Southern, 672, p. 673, Novem- ber, 1914. SALE BY MARRIED WOMAN-VALIDITY. A conveyance by a married woman of the mineral rights in certain described land is void where she had previously conveyed the land to another grantee who had acquired title by adverse possession under the deed.

Jan 1, 1915

By R. Karl Zipf, Z. T. Bieniawski

"A set of fracture profile photomicrographs is presented for fractures generated under mixed mode loading of the Pittsburgh coal. The fractal dimension is used· to characterize the irregularity of these profiles and a tentative relationship is presented between the fractal dimension and the fracture toughness. Surface roughness appears to depend solely on the stress intensity and no other dependence was observed with fracture loading mode, loading rate· or specimen orientation. Observations of crack bifurcations.in fracture profiles can indicate crack growth direction whereas direct surface observations generally cannot in materials such as rock and coal.1 INTRODUCTIONThe production of fine fragments of material as a result of some loading event occurs in many industrial processes. In crushing and grinding, the efficient production of fine fragments is the desired end result; .however, in coal cutting, the production of fine fragments may lead to high levels of respirable dust in the immediate atmosphere with the danger of human lung diseases. Two of the most important sources of fragments in the 1 to 10 micron size range during a cutting process are 1) severe crushing in a zone near the loading tool and 2) subsequent shearing along major crack surfaces that form the larger fragments during material reduction. These and other sources of fine fragments generation are discussed by Roepke (1984) and Zipf and Bieniawski (1986). The physical character of the nearly created major crack surfaces is believed to have a strong influence on the amount of fine fragment generation that occurs during subsequent shearing movement. When the major large fragments initially form, they are ""locked"" in place by the irregular character of the new fracture surface. Only after some relative motion has occurred between fragments are they actually liberated, and the net result is the formation of additional fine fragments. The fine fragmentation is not necessarily limited to the shearing of high points from the macrocrack surf ace since material remaining in the wake of the crack tip is damaged to a substantial depth below the actual crack surface."

Aug 31, 1989

By H. P. Holmes

Tonnage quantities of hafnium metal have been prepared in Kroll-process equipment designed for producing zirconium. Some slight process modifications have been necessary, but overall operation is the same as for zirconium. Hafnium oxide is chlorinated in the presence of carbon and the resultant hafnium tetrachloride reduced by magnesium metal. Byproduct magnesium chloride is removed in a high-vacuum distillation step and the hafnium sponge metal crushed for further use. Arc-melted metal can be forged and rolled to sheet, but the best material produced to date would not be considered cold ductile. INTRODUCTION This investigation is part of the program for the production of pure metals from domestic and foreign ores that has been underway at the Bureau of Mines for several years. It was done in cooperation with the Atomic Energy Commission and the Bureau of Ships.

Jan 1, 1955

By G. W. Birge

Twenty-eight samples, representing the Pittsburgh, Lower Kittanning, Stockton-Lewiston, Coalburg, Winifrede, Cedar Grove, Peerless, No. 2 Gas, Powellton, and Eagle beds, were carbonized by the Bureau of Mines--American Gas Association (BM-AGA) method, and yields of products and physical properties of cokes were determined. Expanding characteristics of 22 of the samples were determined in the Bureau of Mines sole-heated oven. The Kanawha County coals tested were high-volatile A bituminous in rank, with dry, mineral-matter- free fixed- carbon contents ranging from 53.9 to 66.3 percent. With few exceptions, they were chemically satisfactory for metallurgical use, and most of the coke-strength indexes were within the industrially accepted range for high-volatile blending coals.

Jan 1, 1963

By Jr. Kauffman

The data contained in this report were obtained incidental to the Bureau of Mine's investigation of the lime-soda sinter process as applied to the recovery of alumina from siliceous bauxite, kaolin, and other high aluminous materials. The Bureau of Mines was charged by Congress to investigate processes for the production of aluminum from domestic low-grade ores. The Eastern Experiment Station at College Park, Md., conducted laboratory and pilot-plant investigations of the recover-y of alumina by the lime-soda sinter process. Reports by the College Park staff covering the recovery of alumina from these sources have been published. The lime-soda sinter process involves the sintering of the finely ground siliceous bauxite or clay with limestone and soda ash in a rotary kiln. During the sintering the alumina supposedly reacts with the soda ash to form soluble sodium aluminate and the silica combines with the lime to form the insoluble orthosilicate. In the early stages of the investigation it was considered desirable to know the temperatures at which the phase changes occurred during the sintering operation. The total time involved in the passage of any given portion of the charge through the kiln was 28 minutes. The exposure time of the charge to temperatures above 600° C. (decomposition temperature of kaolinite) was, roughly, half the total. The exposure to the full temperature of the kiln, 1,100° C was only 3 minutes. (Subsequently, the maximum kiln temperature and retention time were increased.)

Jan 1, 1949

By R. C. Buehl

Pilot-plant tests have been in progress at the Bureau of Mines, Pittsburgh, Pa., on the recovery of manganese from open-hearth slag.3/4/5/ In the process, 1 the slag is first reduced in a blast furnace to make a high-phosphorus spiegeleisen containing 12 to 22 percent manganese. A slag containing 55 to 60 percent manganese is made from this spiegel by oxidation in a basic-lined converter. The metal from this blowing operation contains about 3 percent phosphorus, 1 percent manganese, and less than 1 percent carbon. Economic efficiency in the manganese-recovery process requires that this metal be converted into steel. Because of its high phosphorus content the metal is suitable for blowing in a basic-lined converter. In most of the tests described in this report, metal of this composition was used as the starting material in a 1-ton, side-blown, basic-lined converter. Although basic-lined converters are not used for steel production in the United states, in Europe a considerable portion of the steel is made in them. Open hearths largely have replaced converters for steelmaking in the United States; mainly because open-hearth steels have better physical properties than converter steels because of lower nitrogen and phosphorus contents. However, by improving converter design and operating technique during the past 15 years, metallurgists have found that low-nitrogen steels with physical properties equal to open-hearth steels can be produced in converters.6/ Tests at Jones & Laughlin steel Corp. with side-blown, acid-lined converters of 3 and 22 tons capacity showed that steel with a low nitrogen content comparable to that of open hearths operating on scrap charges could be made by surface blowing.7/

Jan 1, 1955

By W. E. Anable

The Bureau of Mines studied the purification of commercially available yttrium by melting it in a 100-kw electron-beam furnace. Button-scale melts were made to determine the ultimate purification that could be attained by melting yttrium at 1,733° to 1,770° C at low pressure (0.05 to 0.1 micron) for 1 to 120 minutes. In addition, numerous melts were made to study the effect of doping yttrium with carbon, 17 selected metallic additions, and 3 compounds. Except for nickel and zirconium, the metallic impurities in yttrium were lowered significantly on extended treatment; silicon was lowered only slightly. The nonmetallic impurities} oxygen, nitrogen, and carbon, were not lowered except on short exposures. In isolated instances, the oxygen content was lowered from 5,860 ppm to about 5,000 ppm. In most instances the carbon con-tent was lowered from 545 to about 220 ppm in 20 minutes and then increased again. It was concluded that yttrium cannot be purified by direct heating or by the doping technique employed.

Jan 1, 1965

By Charles L. Ross

A successful placer mine is being operated by the E. T. Fisher Co. on Rock Creek in the South Pass mining district at Atlantic City, Wyo. About 2,800 cubic yards of gravel is dug daily by a gasoline-driven dragline shovel with a 1 1/4-yard bucket and washed in a movable plant with a gold-dredge trommel and standard-dredge sluice boxes; the total cost is about 12 cents per cubic yard. The gold-bearing gravel occupies a narrow valley between two low ranges, of hills. The ground is covered by brush and willows, which are cleared of in the fall by burning after the leaves have dried. The elevation at the mine is 7,600 feet above sea level.

Jan 1, 1935

By F. W. Hoertel

Tungsten from the hydrogen reduction of WF was vapor - deposited to coat MERM (Material Evaluation Rocket Motor ) graphite and rhenium- lined graphite nozzles . These nozzles have surface configurations that preclude the conventional fabrication of high- density- tungsten liners . Operation at 550 ° C produced selectively placed uniform coatings of specified thicknesses at near theoretical density . An acceptable coating could not be deposited on a beryllia nozzle because of an undesirable side reaction between the substrate and one or more of the products of the reduction reaction .

Jan 1, 1964

By T. M. Garland

This report presents a Bureau of Mines assessment of crude oil and associated gas production and reserves that would result from different drilling efforts in the lower or contiguous 48 States during the 1972-85 period. The drilling effort was based upon five growth rate assumptions from the 1971 level. Additions to crude oil reserves were computed for nine cases resulting from the use of three equations for findings per foot drilled and three constant revision factors. The results indicate that the United States will not become self-sufficient in crude oil production by 1985 and also illustrate the lead time required to reverse the decline in oil production. Discussion is limited to three of the nine cases to provide high, intermediate, and low results. More emphasis is on the intermediate case because it is indicative of the most probable trends. The methodology and statistical data are included in the appendices.

Jan 1, 1974

From 1886, the first year shipments were recorded, until 1939, the Leadville district produced over 3,500,000 long tons of manganiferous ore. Of this total, metallurgical-type ores comprised 27 percent and manganiferous iron ores suitable for fluxing in lead smelters made up 73 percent. In 1939, the Bureau of Mines, as part of the strategic minerals investigative program being conducted at the time, requested the Mineral Industries Survey Section of the Mining Division to make a comprehensive study of the manganese resources of the Leadville area. This investigation, owing to the caved and flooded condition of the underground mine workings, was necessarily confined to a study of old maps, production records, and geological reports, and the results were published as an Information Circular in July 1940.

Jan 1, 1949

To design an apparatus that advances the state of the art in gas content testing equipment. The goal of the design is to incorporate improvements in testing sensitivity/accuracy, durability, and ease of operation over existing equipment. It is also desirable for the new design to successfully perform gas content determinations of multiple chemical species from a rock sample.

Jan 1, 1999

By Jon C. Volkwein

The U.S. Bureau of Mines investigated a method of using inert gas to prevent the formation of explosive gas mixtures in auger highwall mining of coal. A combination of gasoline and diesel engine exhaust gases was introduced into the auger drill hole using a short section of pipe located at the collar. Gas samples were taken and analyzed on-site with infrared detectors for oxygen, carbon dioxide, methane, and carbon monoxide. Evacuated bottle samples were also taken and analyzed by gas chromatography in the laboratory. These gas results were analyzed for explosibility. Coal samples from various depths were used to obtain the gas content of the coal using the modified direct method. Personal expo- sure to carbon monoxide was also monitored. The highest methane level observed was 9.55%. The levels of inert gas (carbon dioxide and nitrogen) were sufficiently high to prevent any ignition of the methane. Results showed that for all conditions during mining, gas concentrations were nonexplosive. The gas content of the coal was about 0.30 cm3/g. The maximum personal time-weighted average Sample for carbon monoxide was 20 ppm. This system provides a safe, inexpensive, simple method for preventing explosions during auger mining.

Jan 1, 2010

By J. Dean Warner

In 1984, as part of a project to evaluate Alaskan occurrences of certain critical and strategic minerals, the Bureau of Mines investigated a columbium-bearing regolith on upper Idaho Gulch, near Tofty, AK. The regolith is derived from weathering of a dolomitic marble and consists mostly of iron oxide minerals with accessory apatite, zircon, xenotime, rutile, monazite, and the columbium minerals aeschynite, columbite, and ilmenorutile. Two regolith lenses contain 340,000 lb of columbium resources at an average grade of 0.07 pct. Calculated composite concentrates from two regolith samples (approximately 200 lb each) contained 53 and 57 pct of the columbium at grades of 0.97 and 0.86 pct, respectively. In each case the grade could be improved to 1.1 pct Cb with a sacrifice of 9-pct recovery. The regolith's mineralogy, trace-element geochemistry, and similarity to descriptions of other columbium-enriched regoliths suggest that the underlying marble may be a carbonatite. The lack of associated alkalic igneous rocks and the stratiform nature of the regolith, however, may be interpreted as evidence for sedimentary origin of the marble. The marble and regolith are a lode source for some of the minerals in the Idaho Gulch placer deposit.

Jan 1, 1986

By R. B. Ladoo

"Present Situation:At the beginning of 1920 a general feeling of optimism was noted in many talc-producing districts. The industry seems to have recovered from the temporary depression of the first half of 1919 and many mills are running at capacity production with their entire output for 1920 contracted for. The imports of talc for 1919 were only slightly larger than in 1918 by weight and probably no more by value. Thus foreign competition has not begun to be seriously felt. Several new companies in this country have been organized, some to operate new deposits and others to continue the work done by others.An interesting phase of the present situation is the possibility of increased use of talc in paint. There is a shortage of barium sulfate used as a paint filler. Since, for some uses, talc is considered second only to BaSo4 as a filler for paint, it is possible that part of the shortage could be relieved by an increased use of talc.A series of physical tests upon all pigment materials used in the manufacture of paints is being conducted for the Paint Manufacturers Association of the United States. It is important that all types of talc be represented in these tests. Producers of finely ground talc, 200 mesh and finer, are urged to submit samples of at least two pounds each of these grades that are available to paint makers with trade name and quality data, to the Institute of Industrial Research, 19th & B Streets, N. W., Washington, D. C., where the tests are being conducted."

Jan 1, 1920

By G. F. Friel

A series of experiments in the U.S. Bureau of Mines Safety Research Coal Mine at the Pittsburgh Research Center evaluated the effects of crosscuts on the travel time of carbon monoxide (CO) along an entry to improve the accuracy of a mine-fire locator program. Three entries, ten single crosscuts, and three double crosscuts were instrumented with CO sensors. One-percent CO in nitrogen was released and monitored as it traveled the entries. In addition to dispersion of CO at the front of the CO wave, CO was entrained from the entry into the crosscuts. It was determined for an entry and single-crosscut configuration that the measured travel time for a concentration change of 5 ppm was 27% greater than the predicted time based upon entry volume only, but 13% less than the predicted time based upon entry and crosscut volumes. For an entry and double-crosscut configuration, the measured travel time for the same concentration change was 25% greater than the predicted time based upon entry volume only, but 10% less than the predicted time based upon entry and crosscut volumes. An effective dispersion coefficient for CO dispersion along one of the entries was estimated to be 1.5 m2/ s.

Jan 1, 2010