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Dust Sources and Controls for Multiple-Machine Longwall Faces

Description: Abstract: Longwall mining in lower seam heights may necessitate the use of single-drum shearers to overcome size constraints associated with standard double-drum shearers. To avoid the operational problem of clearance in the tailgate entry with one single-drum shearer, two single-drum machines can be operated on the same face, with each shearer responsible for mining a predefined portion of the face. However, utilization of two shearers on the same face necessitates the positioning of one shear… more
Date: 1995
Creator: Colinet, Jay F. & Spencer, Ellsworth R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of Remote Drop and Pumpdown Placement on Cellular Concrete

Description: Abstract: The hazards to the public posed by abandoned mine shafts are well documented. As private development encroaches on previously mined areas, the potential for fatalities and serious injuries from abandoned mine shafts increases. The U.S. Bureau of Mines has conducted research into cellular concrete as a material for sealing these openings. The current work involves testing the characteristics of cellular concrete before and after it had been pumped or dropped from different heights into… more
Date: 1995
Creator: Boreck, D. L. & Miller, R. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electrochemical Reduction of Titanium in Nonaqueous Solvents

Description: Abstract: Electrorefining of Ti in nonaqueous solvents has been studied by the U.S. Bureau of Mines as a method for recycling impure scrap Ti. Electrochemical behavior of Ti species was investigated using cyclic voltammetry. Research results showed that Ti metal can be dissolved in polar solvents such as dimethylformamide or dimethyl sulfoxide. However, deposition of Ti from these solvents was not successful. Several solvent systems were investigated for electrodepos.tion of Ti but no deposits … more
Date: 1995
Creator: Sibrell, P. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Field Demonstration of Two Pneumatic Backfilling Technologies

Description: Abstract: This U.S. Bureau of Mines (USBM) report summarizes a field demonstration of pneumatic backfiling technologies conducted at the abandoned Hillside Coal and Iron Slope in Vandling, PA. Researchers demonstrated tro pneumatic backfilling technologies recently developed under the USBM's Abandoned Mine Reclamation Research Program, the Pneumatic Pipefeeder and the High-Efficiency Ejector. Both systems had previously been evaluated at the USBM's subsidence abatement investigation laboratory … more
Date: 1995
Creator: Dyni, Robert C.; Burnett, Mackenzie & Philbin, David
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hazards of Conveyor Belt Fires

Description: This report describes a U.S. Bureau of Mines study on the hazards of large-scale conveyor belt fires in underground coal mines, as a function of both air velocity and distance from belt surface to gallery roof. The fire hazards considered were smoke obscuration, toxic effects of carbon monoxide (CO), and elevated air temperatures downstream of the fire. All of these hazards scale with the ratio of fire intensity to ventilation airflow. These hazards were all found to be greater at the lower bel… more
Date: 1995
Creator: Perzak, Frank J.; Litton, Charles D.; Mura, Kenneth E. & Lazzara, Charles P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High-Temperature Cyanide Leaching of Platinum-Group Metals from Automobile Catalysts--Pilot Plant Study

Description: From abstract: The U.S. Bureau of Mines Reno Research Center investigated, developed, and patented a high temperature cyanide leaching process for recovering platinum-group metals (PGM) from automobile catalysts. A batch pilot plant was constructed at the center and operated to demonstrate this technology to industry.
Date: 1995
Creator: Kuczynski, R. J.; Atkinson, G. B. & Dolinar, W. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Human Factors Analysis of Roof Bolting Hazards in Underground Coal Mines

Description: Abstract: The U.S. Bureau of Mines conducted a human factors analysis of hazards associated with roof bolting activities in underground coal mines. Emphasis was placed on hazards related to the movement of the drill-head boom or mast of a roof bolting machine. The objective was to identify hazards and recommend solutions. The data-collection effort consisted of analysis of U.S. Mine Safety and Health Administration accident data; visits to underground mines and interviews with experienced roof … more
Date: 1995
Creator: Turin, Fred C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Improved Grindability of Taconite Ores by Microwave Heating

Description: The 11.S. Bureau of Mines has conducted studies to utilize rapid microwave heating to stress fracture ore samples. Iron ores containing hematite, magnetite, and goethite were subjected to microwave energy in batch operations at 3 kW and heated to average maximum temperatures between 840 and 940 *C. Standard Bond grindability tests showed that microwave heating reduced the work index of iron ores by 10 to 24 pct. In a microwave chamber designed to simulate a continuous throughput operation at 3 … more
Date: 1995
Creator: Walkiewicz, John W.; Lindroth, David P. & Clark, Andrea E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Improved Performance of Linear Coal Cutting Compared with Rotary Cutting

Description: From abstract: The linear cutting system, developed by the U.S. Bureau of Mines, uses geometric principles developed by Cardan to produce a nearly constant cut depth. The new system has been extensively tested in a synthetic material under laboratory conditions to verify mechanical capability and to identify operational characteristics. This report details the improved performance versus rotary cutting.
Date: 1995
Creator: Roepke, Wallace W.; Hanson, B. D.; Olson, R. C.; Wingquist, C. F. & Myren, T. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Influence of Environmental Factors on Spark Ignition Probability

Description: Abstract: In past years, the U.S. Bureau of Mines has been involved in safety research that could ultimately relate the conditions of spark testing and actual use by estimating the simple ignition probability of a circuit in question. A major problem in estimating this probability is that results show a significant variability, even though gas mixtures and electrical parameters may be closely controlled. Some researchers have suggested that the ambient environmental conditions of the testing ma… more
Date: 1995
Creator: Peterson, Jeffrey Shawn
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of Acid Production, Leaching, and Transport of Dissolved Metals at an Abandoned Sulfide Tailings Impoundment: Monitoring and Physical Properties

Description: Abstract: Researchers at the U.S. Bureau of Mines conducted a long-term groundwater monitoring and site characterization program at an abandoned 10-ha, acid-producing, copper-gold tailings impoundment in north-central Washington State. The purpose was to investigate contaminant release and transport, and attenuation mechanisms in the tailings, sediments below the tailings, and gravels downgradient of the impoundment. This report summarizes the monitoring results and physical properties of the t… more
Date: 1995
Creator: Stewart, Bill M.; Williams, B. C. & Lambeth, R. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of Optimum Thrust, Cutting Speed, and Water Pressure for Tungsten Carbide and Polycrystalline Diamond Compact Roof-Bolt Drill Bits

Description: Abstract: Laboratory tests were conducted at the U.S. Bureau of Mines to determine the effects of roof-bolt drilling parameters on penetration rate in sandstone using tungsten carbide alloy (WC-Co) and polycrystalline diamond compact (PDC) drill bits. During the tests, water pressure of 552 kPa was found to be adequate for removing the cuttings from the tops of drill holes. Test results show that for both types of bits, penetration rate increased when thrust was raised from 227 to 1,588 kg. Whe… more
Date: 1995
Creator: Sundae, Laxman S.; Smelser, Thomas W. & Howie, Wayne L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Kinetic Model for Conventional Flotation of Coal

Description: The U.S. Bureau of Mines has developed a computer model to 'describe a flotation process. Coal data from conventional flotation has been converted to a simple, two-parameter kinetic model developed by Reuter and van Deventer (j,2 3. Each set of coal data was represented by two constants, a and a, and an average flotation rate. The success of the model was demonstrated when the calculated and experimental recoveries showed good correlation. The two-parameter model allows complex data to be defin… more
Date: 1995
Creator: Susko, Frank J. & Stanley, Don A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Longwall Gate Road Stability in a Steeply Pitching Thick Coal Seam with a Weak Roof

Description: The U.S. Bureau of Mines (USBM) conducted ground pressure analysis of a wide abutment-type chain pillar in a two-entry gate road of a Western U.S. coal mine with an extremely weak immediate roof. About 15 m of fragile, low-strength mudstone lies between the seam and the lowest competent roof member. Three- and two-entry gate road designs with several pillar sizes and various secondary support systems have been employed to improve tailgate-entry stability, with varying results. This report discu… more
Date: 1995
Creator: Barron, Lance R. & DeMarco, Matthew J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Numerical Modeling Analysis of Stress Transfer Modification Concepts for Deep Longwall Mines

Description: Abstract: This U. S. Bureau of Mines (USBM) report evaluates three stress-transfermodification concepts for their potential in reducing longwall gate road stresses and closures. In each of the three concepts - packwalling, gob infilling, and entry filling - support structures are constructed on the headgate side of the panel parallel with or inby the face line. When the headgate becomes the tailgate of the adjacent panel, these structures are in place to accept stresses transferred from the min… more
Date: 1995
Creator: Vandergrift, Thomas L. & Jude, Charles V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Petrographic and Geochemical Analyses of Leach Samples from Artillery Peak, Mohave County, Arizona

Description: Abstract: The first step in determining whether Mn can be recovered by in situ leaching is to develop and test a selective lixiviant. Two column leach tests and one core leach test were conducted by the U.S. Bureau of Mines on Mn oxide ore using aqueous sulfur dioxide (SO2) as the lixiviant. The column tests showed that aqueous SO2 could selectively dissolve available Mn oxides from calcite-rich ore in a heap leach system. However, the core test showed that calcite gangue side reactions can hav… more
Date: 1995
Creator: Brink, Susan E.; Blake, Rolland & Marozas, Dianne
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Radar Positioning System Accuracy Test

Description: Abstract: The U.S. Bureau of Mines conducted research to develop an accurate, real-time, position monitoring and warning system for the vehicles used in surface mining. The product of this research will be technology to reduce accidents and injuries associated with the operation of surface mining haulage equipment. The position monitoring system should reduce accidents related to vehicle position and also increase the efficiency of haulage operations. This research was conducted in preparation … more
Date: 1995
Creator: Utt, Walter K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Rapid Separation of Heavy Rare-Earth Elements

Description: The U.S. Bureau of Mines investigated the separation of heavy rare-earth elements (REE) in an ion-exchange process. An ion-exchange column consisting of two sections, a loading section and a separation section, provides high levels of REE loading and good REE separation with an expected processing cycle of less than a month, while current ion-exchange technology requires more than 5 months. A different resin is used in each section: sulfonic resin in the loading section and iminodiacetic resin … more
Date: 1995
Creator: Moore, B. W.; Froisland, L. J. & Petersen, A. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Reactivity Studies During Drying and Relocation of Lead-Zinc-Gold Tailings: Phase 1 - Preliminary Evaluation and Laboratory Testing

Description: The U.S. Bureau of Reclamation requested U.S. Bureau of Mines (USBM) assistance in developing design data for moving lead-zinc-gold tailings from their current location without disrupting the existing chemically stable conditions. This report presents results of USBM work in determining (1) the minimum required time to air dry the tailings to approximately 20 pct moisture under various drying conditions both in the laboratory and in the field, (2) the degree of oxidation or reduction that occur… more
Date: 1995
Creator: Froisland, L. J. & Lym, P. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Reducing Respirable Dust Levels During Bag Conveying and Stacking Using Bag and Belt Cleaner Device

Description: Abstract: The U.S. Bureau of Mines has designed and tested a system called the Bag and Belt (leaner Device (B&BCD) to reduce dust levels in and around the bag conveying and stacking process. The device physically cleans either 22.7 kg (50 lb) or 45.4 kg (100 lb) paper bags by using a combination of brushes and air jets. It is completely self-contained and is kept under negative pressure by a baghouse to ensure that dust and product removed from the bags during cleaning does not flow into the wo… more
Date: 1995
Creator: Cecala, Andrew B.; Timko, Robert J. & Prokop, Alexander D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Reduction of Airborne Dust Generated by Roof Bolt Drill Bits Through the Use of Water

Description: Abstract: In the vast majority of American coal mines, roof bolt holes are drilled dry, mainly because of mine operator concern with the spent water creating adverse working conditions. Wet drilling, however, can increase drilling rates and the effective lifetime of the drill bits used. This study, carried out as part of an ongoing cooperative research program between the U.S. Bureau of Mines and the University of Missouri-Rolla, shows that the large volumes of water conventionally used in wet … more
Date: 1995
Creator: Sundae, Laxman S.; Summers, David A.; Wright, Douglas & Cantrell, Bruce K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Structural Analysis of a Mechanized LHD Trench Undercut Caving System

Description: Abstract: This U. S. Bureau of Mines (USBM) report presents results of stress analyses and field observations to investigate the effects of elevated trench drifts on the structural stability of rock mass zones surrounding a production draw drift in a mine utilizing a mechanized load-haul-dump (LHD) trench undercut panel caving system. A two-dimensional boundary-element mine stress model was developed to predict the locations and extent of damaged rock mass zones surrounding draw drifts where ad… more
Date: 1995
Creator: Jude, Charles V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Synthesis of Advanced Ceramic Compounds by Intercalation

Description: The U.S. Bureau of Mines investigated the synthesis of advanced ceramics (SiC+AlN, SiAlON, SiC+Al 203 , and Si 3N4 +AlN) from natural clays (kaolin, halloysite, or montmorillonite) by an intercalation and heat treatment method. This process includes the steps of refining a clay, intercalating organic chemicals into its layered structure, drying the intercalated mixture, firing the treated structure at certain temperature ranges in controlled atmospheres to form desired compounds, and grinding t… more
Date: 1995
Creator: Kwong, Kyei-Sing & Bennett, James P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Teleoperation of a Compact Loader-Trammer

Description: Abstract: The U.S. Bureau of Mines has developed a portable, inexpensive teleoperation system for mobile hard-rock mining equipment. The system was tested on a compact loader-trammer in a simulated stope. The teleoperation system includes radio remote control and computer-assisted navigation. A recent enhancement includes video cameras mounted on the machine to provide visual information to the operator. This system allows the operator to remain in a safe location while operating the machine fr… more
Date: 1995
Creator: Ruff, T. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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