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Laboratory Studies of the Trent Process

Description: Report issued by the U.S. Bureau of Mines detailing the laboratory-scale tests of the efficiency of the Trent process in cleaning coal, in which powdered coal, water, and oil is agitated or beaten together to remove impurities. The report includes details in tables detailing the efficiency varying the type and amounts of coal, oil, and water on the process.
Date: July 1921
Creator: Perrott, G. St. John & Kinney, Selwyne Perez
open access

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.
open access

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.
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.
open access

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.
open access

Ten-Cycle Bench-Scale Study of Simplified Clay-Hydrogen Chloride Process for Alumina Production

Description: From abstract: This U.S. Bureau of Mines (USBM) research simplified an earlier hydrogen chloride (HCl) leachsparge process developed by the USBM to recover reduction-grade alumina from domestic kaolin clay. Improvements were made by decreasing the initial leaching acid concentration from 25 to 20 pct, decreasing the leaching time from 1 to 2 h to 15 to 30 min, eliminating the solvent extraction step for Fe removal, and eliminating the step to recover the Al content of the bleedstream circuit. A… more
Date: 1995
Creator: Shanks, D. E.
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.
open access

Well-Point Containment of Impoundment Leakage

Description: Research was conducted to evaluate the effectiveness of a well-point dewatering system in conjunction with a french drain to intercept waste impoundment leakage while reducing the volume of waste water requiring treatment. A well-point dewatering system composed of 585 production wells was installed around the perimeter of a leaking impoundment that previously used only a french-drain system for leakage control. The placement of the well-point system was designed to intercept and remove the lea… more
Date: 1995
Creator: Smith, C. W.
open access

Bending Fatigue Tests on Flattened Strand Wire Rope at High Working Loads

Description: Abstract: The U.S. Bureau of Mines established a wire rope research laboratory to examine the factors that affect the safety and the useful life of wire rope. In the most recent work, two 32-mm 6x27H flattened strand ropes were degraded on a bending fatigue machine. The two tests were run at constant loads of 285 and 347 kN or safety factors of 2.5 and 2. Nondestructive and tensile strength tests were performed on samples of the ropes to determine the relationship between rope deterioration and… more
Date: 1995
Creator: Wang, Richard C. & Shapiro, David E.
open access

Characterization of Dredged River Sediments in 10 Upland Disposal Sites of Alabama

Description: Abstract: The U.S. Bureau of Mines, Tuscaloosa Research Center, in cooperation with the U.S. Army Corps of Engineers under interagency Agreement No. 14-09-0078-1510, conducted a comprehensive sampling program of 10 upland disposal sites along the Alabama, Black Warrior, and Tombigbee River systems in Alabama. Samples from each site were characterized according to particle size, chemical analysis, mineralogical content, and potential end use. Additionally, samples were subjected to the Toxic Cha… more
Date: 1995
Creator: Smith, C. W.
open access

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
open access

Development of Coal Combustion Sensitivity Tests for Smoke Detectors

Description: Standard smoldering and flaming combustion tests using small coal samples have been developed by the U.S. Bureau of Mines as a method to evaluate the response of a smoke detector. The tests are conducted using a standard smoke box designed and constructed according to Underwriters Laboratories. The tests provide a standard, easily reproducible smoke characteristic for smoldering and flaming coal combustion, based upon a comparison of the smoke optical density and the response of a standard ioni… more
Date: 1995
Creator: Edwards, John C. & Morrow, Gerald S.
open access

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.
open access

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
open access

Detection and Control of Spontaneous Heating in Coal Mine Pillars--a Case Study

Description: This U.S. Bureau of Mines study examined spontaneous heating episodes in coal mine pillars in an active underground coal mine. The information obtained from these incidents was then analyzed to learn which sampling methods provided the earliest indication of pillar heating. The objective of this study was to discover if the location of future events of pillar spontaneous heating could be inferred from the available information. The spontaneous heating-prone area in this evaluation involved pill… more
Date: 1995
Creator: Timko, Robert J. & Derick, R. Lincoln
open access

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.
open access

Timing and Duration of Subsidence Due to Longwall Mining

Description: Subsidence data gathered by the U.S. Bureau of Mines over a series of longwall panels in the Pittsburgh Coalbed were studied to obtain insight as to the role of time in the subsidence process. It was found that subsidence began essentially with undermining and was completed within 1 year. The progress of the subsidence was dependent upon location above the panel. Subsidence in the central area of the subsidence trough, where subsidence is the greatest, was about 90 pct complete by the time the … more
Date: 1995
Creator: Jeran, Paul W. & Trevits, Michael A.
open access

An Adaptive System for Process Control

Description: Abstract: Researchers at the U.S. Bureau of Mines (USBM) have developed adaptive process control systems in which genetic algorithms (GA's) are used to augment fuzzy logic controllers (FLC's). GA's are search algorithms that rapidly locate near-optimum solutions to a wide spectrum of problems by loosely modeling the search procedures of natural genetics. FLC's are rule-based systems that efficiently manipulate a problem environment by modeling the "rule-of-thumb" strategy used in human decision… more
Date: 1995
Creator: Karr, Charles L.; Gentry, E. J. & Stanley, D. A.
open access

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.
open access

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
open access

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.
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