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By Jon K. Ahlness

The Bureau of Mines conducted laboratory and field experiments to determine tne amount of permeability reduction in uranium sandstone after its exposure to different drilling fluids. Seven polymer and two bentonite fluids were laboratory-tested in their clean condition, and six polymer fluids were tested with simulated drill cuttings added. Sandstone cores cut from samples collected at an open pit uranium mine were the test medium. The clean fluid that resulted in the least permeability reduction was an hydroxyethyl cellulose polymer fluid. The greatest permeability reduction of the clean polymers came from a shale-inhibiting synthetic polymer. Six polymer fluids were tested with simu-lated drill cuttings added to represent field use. The least permeability reduction was obtained from a multipolymer blend fluid. A field experiment was performed to compare how two polymer fluids affect formation permeability when used for drilling in situ uranium leaching wells. For this test, the polymer fluid with the best laboratory results (multipolymer blend) was compared with a commonly used polymer fluid (guar gum) that gave poorer laboratory results. When fluid injection rates for the four wells drilled with the guar gum were compared with those for the four drilled with the multipolymer blend, no statistically significant difference was found.

Jan 1, 1984

By Carl H. Beal

The oil industry in the United States is further advanced than in any other country, because of American initiative and the development of industries dependent in some way on petroleum or its products. For this reason the output has constantly increased (fig. 1), and as a result this country has produced more than half of the total output of the world. Trw total past output of the world is approximately 7,000,000,000 barrels of 42 gallons each; of this the United States produced about 4,000,000,000 barrels, or about 57 per cent. The limit of production in this country is being approached, however, and although new fields undoubtedly await discovery, the yearly outpnt must inevitably decline, because the maintenance of a given output each year necessitates the drilling of an increasing number of wells. Such an increase becomes impossible after a certain point is reached, not only because of a lack of acreage to be drilled, but because of the great number of wells that will ultimately have to be drilled. According to figure 1, the daily production per well each year has increased during the last few years. However, this increase is abnormal, being caused by the new pools brought in. Although such a condition may continue for several years, the average production per well will finally begin to decrease on account of the lack of new pools to make up for the normal decline in production of the old ones.

Jan 1, 1919

By D. Harrington

The occurrence of dust in mines has always been a source of trouble, but for any years, and virtually up to the beginning of the present century, relatively little of a definite nature was known as to the numerous ill effects of dust in mining operations. Even today, with the west amount of time given and attention paid (for at least 40 years in various, countries) to research and observation en dust in mining, and in spite of the experience with it, much information remains to be obtained, before definite, well-authenticated statements can be made as to numerous features connected with the occurrence of dust in Dines an of its effect upon the health and safety of the worker. One statement that can be made with relatively good assurance of being uncontradicted in that dust is a real menace to the well-being of mine workers, and this includes both health and safety. In addition, dust in and around mines and mining plants is one cause of large financial losses to mine owners and operators. FORMATION OF DUST IN COAL MINES IN THE UNITED STATES One definition of mining is "the processes by which useful materials are obtained from the earth's crust; " since virtually all of the useful materials of or in the earth's crust either are solids or must be reached by penetrating through solids, the materials that are moved in mining must necessarily be broken or disrupted, so that almost every phase of the work of loosening the material and transporting it is likely to produce dust.

Jan 1, 1939

By Wallace W. Key

Mineral raw materials produced in California, other States, and foreign countries were purchased for consumption in quantities valued at over $60 million at 800 of the 1,200 chemical plants operating in California in 1960, according to questionnaires completed by company officials. These and other data received from mineral consumers, producers, dealers, and Government agencies formed the basis for this the first of a series of reports designed to present the intricate features and relationships controlling mineral raw material supply and demand in California industries. The results of this study indicated certain changes in use patterns of minerals in chemica 1 manufacturing; a shift in requirements from metals to nonmeta ls, from inorganics to organics, from natura 1 to synthet ic materia ls , and from distant to local sources of supply.

Jan 1, 1965

By D. W. Bridges, S. R. Borrowman

Thorium and yttrium oxides were recovered from siliceous ores of the Powderhorn , Colo . , area . Processing comprised ( 1 ) acid curing and subsequent ( 2 ) acid baking , ( 3 ) leaching , and ( 4) solvent extraction of thorium , using a primary alkylamine , and yttrium , using di - 2 - ethylhexyl phosphoric acid . About 95 pct of the contained thorium and yttrium was recovered from ore containing 1.2 pct Th02 and 0.5 pct Y₂ 03. The thoria product was 99 pct Tho ; the yttria product was 77 pct Y₂ 03. A 150 - to - 1 concentration ratio was effected on the latter , but some contaminating lanthanon - group oxides remained .

Jan 1, 1964

By A. G. Galaitsis

This report summarizes the work performed under the USBM Contract No. J0245001. The purpose of this work was to expand and improve the scope and accuracy of the method developed under USBM Contract No. J0113056 for the prediction of the number of overexposed workers in the mining industry. A significant portion of the noise data were acquired during mine visits-that took place in the-course of this contract. These data were obtained with time-resolved dosimeters which among other things store a time history of the sampled noise for an eight hour work period. The remainder of the noise data have been obtained from MSHA files and from other BoM-sponsored projects. The report reviews the prediction model, discusses the model's assumptions and approximations, describes the function of the developed software, offers typical examples on the use of the software and includes plots of the newly acquired noise data records.

Jan 1, 1986

By C. S. Tout

While investigating methods for determining the best temperatures for hot-working experimental stainless steels, the Bureau of Mines Albany Metallurgy Research Center developed a machine in which hot-twist tests could be made in a few minutes. This machine is similar to some used previously except that specimens are heated by induction instead of by radiation, and their temperature is measured by a calibrated radiation-detection unit instead of by a thermocouple. In. developing the technique for using the new machine, tests were made on specimens of medium-carbon steel, mild steel, and AISI (American Iron and Steel Institute) type 304 stainless steel. Tests also were made on as-cast specimens and preworked specimens of experimental AISI type 202, low austenitic stainless steel, and as-cast specimens of AISI type 301 experimental stainless steel. The optimum hot-working temperatures were determined for all types of steel tested. Also, data were gathered on the effects of test speed and temperature on torsional strength and the effect of twisting on tensile stress in the specimen.

Jan 1, 1962

By Fun-Den Wang

This report presents theoretical studies and experimental work dealing with the detection of dangerous roof and pillar conditions in underground mines through measure¬ment of temperature differences on the surface of the mine opening. The theoretical work is directed at modeling the circumstances where a loose slab of rock might be detected. The experimental work provides input data for the theoretical models. At the beginning of the project, little was known by the authors of the conditions that would permit detection of a loose slab of rock or coal by measuring the surface temperature differences. The U.S. Bureau of Mines had found that there were detectable surface temperature differences on the roofs and pillars of mines. The Bureau contracted with Colorado School of Mines to measure temperature profiles around mine openings in an effort to learn if the temperature differences they had detected were directly related to loose pieces of roof and pillar rock. The Bureau was principally interested in learning if loose rock could be found in coal mines by measurement of surface temperature differences with an infrared thermometer.

Jan 1, 1972

By Edmund S. Leaver, Charles E. Van Barneveld

In response to numerous requests from metallurgists and operators for information regarding the status of the sulphur dioxide leaching process , developed at the Southwest experiment station of the U. S. Bureau of Mines , Tucson , Ariz . , the following statement has been prepared . A more complete report is now in course of publication and will appear as Technical Paper 312. This process was devised to provide a cheap and efficient method for treating the so- called "porphyry " copper ores of the Southwest which generally contain both " sulphide " and "nonsulphide " copper minerals , mixed in such proportions that they can only be satisfactorily treated by a method which will concurrently recover both the sulphide copper and the nonsulphide copper . The latter term has been adopted to include all the minerals commonly referred to in operating phraseology in the mills of the Southwest as " oxidized" , " oxide " , or " soluble " copper . confident that the sulphide dioxide leaching process , as developed by us with the cooperation of the Miami Copper Co. and the Arizona Copper Co. , is suitable and commercially available for a wide range of ores .

May 1, 1922

By Diana K. Schimmelpfennig

Assessment of revegetation success on mined lands is a difficult, time consuming task and has been the subject of a number of controversies. Present regulations require that both plant cover and aboveground plant biomass be measured for use in making that assessment. Of these two variables, biomass is the most time consuming to measure and requires destructive sampling, a most undesirable requirement on fragile, recently revegetated areas. On the other hand, plant cover can be estimated using the point-frame method which is relatively nondestructive. In addition, vegetation can be sampled more uniformly with the point frame and in less time if species composition measures are to be made. A study was done to evaluate the predictability of aboveground biomass production on revegetated mined sites and adjacent native prairies using plant cover estimates made with the point frame method. The predictability of biomass production by cover estimates bears on the need for both measurements in assessing revegetation success. In general, a positive, statistically, significant correlation was demonstrated between plant cover (estimated by the point frame) and aboveground biomass (estimated by the harvest method) regardless of community type (mined or native), species composition, diversity or level of biomass production. However, the latter did have their effects on the relationship and must be accounted for in any predictive equations (that is to say, the predictive equations must be considered site-specific). Considering the relationship observed between the two parameters, cover estimation may be a sufficient indicator of revegetation success, especially where time and minimization of disturbance are critical.

Jan 1, 1982

By Nan C. Jensen

Modern high-temperature metallurgical processes have created a demand for raw material for furnace parts and lining that not only will with-stand high temperatures is but will not react with the substance being melted in the furnace. Spark-plug insulators, laboratory ware, tanks for the glassmaking making industry, and saggers and kiln furniture for the chinaware and pottery trades also must be made of materials hat have high melting points. Among the minerals that can be employed for such refractory uses ore those commonly known as the "sillimanite group' -kyanite, andaluste, sillimanite, and dumortierite - and the allied minerals topaz and pinite. Consideration of the occurrence, properties, qualities, uses, and sources of supply of these commodities and the markets for them constitute the subject of this paper. General Features of Kyanite and Related Minerals Kyanite, andalusite, and sillimanite ire composed of three elements - aluminum, silicon, and oxygen ? and are called aluminum silicates. The have

Jan 1, 1943

By Sidney Katell

Philippine laterite and serpentine ores can be utilized in an electric furnace operation to produce both a steel ingot and a ferronickel product. Figure 1 is a schematic interpretation of a plant in which laterite and serpentine ores are processed separately to obtain both ferronickel and steel as products. A relationship of estimated capital requirements and probable returns has been established in this study for a plant of this type. No attempt has been made to evaluate the risks involved in commercial operations. At such time that the project might be constructed and placed in operation, changes in the costs of material, labor, and power may materially affect the profitability aspects of this study. One of the uncertainties involved in the economic evaluation is the cost of mining, handling, and shipping the ores. It is on this basis that the cost of ore delivered at the plant is assumed to be variable at $3, $5, and $7 per net ton (dry basis). For all other costs a plant site at Iligan City, Philip-pine Islands, has been assumed in preparing the economic characteristics for a plant that will process 2,000 tons4/ of ore per day. Results of the study, for the 2,000-ton plant, with all monetary values expressed in terms of United States currency (Philippine peso valued at $0.50), are summarized as follows:

Jan 1, 1962

By Steven W. Schmauch

The Sugarloaf RARE II area (No. 5296) covers 11,100 acres in the northern part of the White Mountain Range, in the Inyo fictional Forrest. It is in Nevada, about 45 mi north of Bishop, California. A mineral survey was conducted by On U.S. burro of Mines in 1982 and by the U.S. Geological Survey in 1980-1982. The Bureau reviewed pertinent literature, searched Esmeralda and Mineral County mining records, obtained current claim information from the administrative agencies, and contacted claim owners. Thirty-six properties were examined, and 674 samples were taken from them to help assess win oral resources and potential. The Geological Survey evaluated the regional mineral potential by geologic, geochemical, and Geophysical surveys.

Jan 1, 1983

By John J. Mulligan

Coalbeds were discovered in outcroppings of the Beacon group of sediments on the north end of the Willett Range ( altitude 77 ° 11 ' S , longitude 160 ° 20 ' E ) , Victoria Land , Antarctica , in December 1960 during an investigation undertaken as part of the U.S. Antarctic Research Program under the auspices of the National Science Foundation . Three separate exposures of coal or coaly material were found . Two of the exposures contain , respectively , eight and four beds of hard , compact , finely banded attrital coal ranging in thickness from 8 feet downward to a few inches , and reported to range in rank from mediumvolatile bituminous to semianthracite . The coals are associated with carbonaceous shales containing an abundant assemblage of fossil plants resembling those associated with the Permian coals of Australia and other Gondwana areas . The third exposure , apparently somewhat higher in the stratigraphic sequence , contains only coaly plant fragments scattered through a thin conglomerate and overlying sandstones . A sandstone bed that overlies these coal - bearing sandstones contains abundant logs and fragments of silicified wood . Preservation of features is poor , but one segment of a silicified stem suggests comparison with Rhexoxylon , a gymnospermous tree that usually is considered indicative of Triassic age . The Beacon sediments in this area have been invaded , broken , and uplifted by a massive series of diabase sills and dikes greater in volume than the intruded sediments . The heat emitted by these intrusives must have advanced the metamorphic development of the coals . However , there is no evidence of alteration to graphite , and coal found in direct contact with a diabase sill contains no vesicles or other usual evidences of natural coking . Either the pressure of overlying rocks inhibited the development of coke , or the coals had been metamorphosed beyond the coke forming stage before the igneous intrusion .

Jan 1, 1963

By C. Froger

Since its creation in 1950, the Centre d'Etudes et Recherches des Charbonnages de France at Verneuil-en-Halatte (Oise) has been conducting many investigations concerned with airborne dust measurements, particularly in underground mines. The work has resulted in the development, a few years ago, of a new process of dust sampling, whereby the airborne dust particles are collected by a rotary filter of polyurethane foam rotating at high speed within 8 housing.

Jan 1, 1973

By Fun-Den Wang

Rock bolting has become a major method of coal mine roof support because of its effectiveness, economy, and convenience. The polymeric-resin-bonded bolt has generally proved to be more effective than the mechanically anchored bolt, but the higher cost of the resin bolt limits it to applications where the increased support is essential. The low-cost high-early-strength cement grout developed during this project will encourage more widespread use of fully grouted roof bolts provided practical installation techniques can be developed. Laboratory tests of four types were performed on various rapid-set and accelerated cement products to find a material with properties suitable for replacing resins. A proprietary gypsum cement was ultimately used with good success. A field test of the cement grout was made in an operating coal mine. An intersection was bolted in the standard pattern with cement-grouted bolts and instrumented. A nearby resin-grouted intersection was also instrumented and observations were carried out in both intersections for 2 months. No substantial difference was found between the support provided by the cement and the resin.

Jan 1, 1976

By Roy C. Bartholomae, Jeffrey Shawn Peterson

1. INTRODUCTION In the early 1980s, the U.S. Department of the Interior’s Bureau of Mines Pittsburgh Research Center required that a large reverberation acoustic facility be constructed. This facility was designed to determine the sound power level emissions of mining equipment, especially continuous miners and jumbo drills. A contract for a conceptual design of a reverberation chamber was awarded to Wyle Laboratories of Huntsville, AL, which had extensive experience in the design, construction, and accreditation of acoustical reverberation chambers. The following standards were referenced as guidelines for the design of the chamber: ANSI S1.31-1980, “Precision Methods for the Determination of Sound Power Levels of Broadband Noise Sources in Reverberation Rooms” and ANSI S1.32-1980: “Precision Methods for the Determination of Sound Power Levels of Discrete-Frequency and Narrowband Noise Sources in Reverberation Rooms.” Specific requested criteria included that the room be large enough to accommodate typically large mining equipment and that there be adequate acoustical modal density in the frequency range of interest. It was also required that the room dimensions would support broadband acoustical measurements down to the 100 Hz third octave band. With the closing of the Bureau of Mines in 1996, this reverberation chamber lay dormant for a number of years. However, this facility is now part of the National Institute for Occupational Safety and Health’s (NIOSH’s) Pittsburgh Research Laboratory (PRL). One of NIOSH’s missions is to decrease noise induced hearing loss among the nation’s mineworkers. To this end, PRL researchers are refurbishing and instrumenting this reverberation chamber to facilitate assessment of the various engineering controls being developed to decrease the sound power level emissions of mining equipment. Early on, this work has sought to bring the chamber up to the level of ISO 3743-21 standard for engineering grade measurements for broad-band noise, with a longer range goal of improving the lab to meet the requirements of ISO 37412standard for broadband precision grade measurements. 2. DESIGN OF THE REVERBERATION CHAMBER The nominal room dimensions are 18.3 meters long by 10.3 meters wide with a height of 6.7 meters. The chamber volume is 1,286 cubic meters. These dimensions are important, as few reverberation facilities are large enough to test typically huge mining equipment. The floor is poured concrete with a sealer to make it acoustically reflective. The walls are built of hollow concrete block, 16 inches long x 8 inches high by 12inches thick. Each block has two hollow cores. The hollow block cores were completely filled with concrete with horizontal and vertical steel reinforcing bars 16 inches on center. This was done to supply a

By H. S. Kalman

A table of factors, for rapid, accurate calculation of the volume of pure helium in cylindrical steel containers, is presented. By use of the table the volume of helium in a container, at base conditions of 14.7 psia and 70° F, can be calculated from the observed pressure and temperature of the helium and the known internal volume of the container. The table covers a pressure range from 0 to 4,500 psia in 10 psi increments and a temperature range of 0° to 120° F in 2° increments. The calculation of volume requires a single multiplication, using a factor from the table and the known internal volume of the container. A discussion and evaluation of the accuracy obtainable and a derivation of the formula used (which takes into account compressibility of helium, thermal expansion of steel containers, and the stretch of steel due to internal pressure) are presented. An example showing how the table can be used is given also.

Jan 1, 1963

By William R. Archibald

This report presents the results of a program demonstrating the technical and economic feasibility of hydraulic borehole mining of uraniferous sandstone. This mining technique involves the drilling of a borehole from the surface down into the ore body. A borehole mining tool consisting of a high-pressure cutting jet and a slurry jet pump is lowered down the borehole. Water from the high-pressure cutting jet cuts into the sandstone formation generating a water-sand slurry which flows to the slurry jet pump and is pumped to the surface. The cutting jet is rotated and moved up and down from the surface, thereby generating a cavity in the formation. When the cavity size reaches a point beyond the effective radius of the cutting jet, the mining tool is moved to an adjacent borehole and the process is started again. This program was carried out in four phases. Phase I included modifications to the borehole mining system (built and tested under a previous contract, No. H0252007, for the mining of coal) and factory tests of the jetting system. Phase II covered the field tests and a public demonstration. Phase III involved nozzle and equipment modifications and factory tests. Field testing continued under Phase IV along with an evaluation of this method. The field tests were conducted successfully on Rocky Mountain Energy Company's Nine Mile Lake property near Casper, Wyoming. Results indicate that; hydraulic borehole mining of uranium is technically feasible (300 tons of uraniferous sandstone were mined from a depth of 90 ft) and the hydraulic borehole method is economically attractive. However, additional testing is required to clearly define the economic feasibility.

Jan 1, 1978

By Martin J. Gavin

The oil- shale studies of the Bureau of Mines , conducted in cooperation with the State of Colorado and the University of Utah , have for their primary purpose the determination of retorting and refining conditions most favorable for obtaining the highest yields of most satisfactory products . Oil shales , typical of the deposits in several States , are retorted in carefully controlled retorts of differe types , the conditions being varied in successive runs as the results indicate that improvement in the yield and quality of the products most desired may be expected . Each shale presents a somewhat different problem , for it has been found that different shales treated under similar conditions yield products of different natures , and also that the same shale will yield products of different natures when retorted under different conditions . Some shales apparently can not be made to yield , under any set of conditions , products of so high an order as are yielded by other shales . This indicates that the oil -yielding materials of certain shales differ in constitution and in their manner of breaking down when undergoing destructive distillation . Other shales appear to contain oil - yielding materials that resemble each other closely as regards chemical constitution , yet they require some. what different conditions of treatment , if products of similar nature are to be produced from each . In such cases the controlling factors seem to be the richness of the shale that is , its content of oil -yielding material and the physical and chemical nature of its mineral parts .

Mar 1, 1922