Search Documents

By A. W. Effinger

The Bureau of Mines used regression analysis and applied statistical methods in an effort to rationalize the results of an experiment examining the effects of certain variables on carbon deposition in a reservoir for thermal recovery of petroleum. Although none of the 15 trials of the original experiment resulted in the response of weight-percent of carbon regarded by the experimenter as adequate, values calculated using canonical analysis in two trials yielded responses 33 and 54 percent higher than the minimum acceptable figure. The actual responses differed by less than 3 and 6 percent, respectively, from the predicted responses. Methods are described for defining a path of increasing response based on the minimum point and the response surfaces and for defining a set of values for the parameters in question, which result in increased response, A detailed explanation of the mathematical process used in this analysis is presented in the appendix for ease in computer programing the technique.

Jan 1, 1970

By D. E. Hirsch

A systematic procedure for separation, characterization, and semiquantitative analysis of high-boiling petroleum distillates was developed by the Bureau of Mines and applied to a 370° to 535° C distillate of Wilmington, Calif., crude oil. Separation procedures employed were isothermal and molecular distillation, chemical treatment, silica-alumina adsorption, and gel permeation chromatography. Characterization and analysis were accomplished by gel permeation chromatography correlations and mass and nuclear magnetic resonance spectrometry. These data should be useful in improving petroleum processing and utilization and in achieving the energy conservation inherent therein.

Jan 1, 1974

By Larry G. Stolarczyk

1.0 FRAMEWORK FOR COMPARISON This document describes the decision factors that bear on the selection of the modulation process for the wireless underground medium frequency (MF) communication system. The selected modulation process must satisfy the Bureau of Mines stated objective of improving general communications within an underground mine. The improvement being sought includes the development of a wireless communication technology of measurable benefit to both mine safety and mine productivity. The improvement will allow wireless communications paths to exist between roving miners. The wireless communication paths will also be made compatible with the existing underground telephone system to extend paging and voice communication throughout the underground mine. The new wireless equipment will include man-pack, vehicular, repeater, and base station transceivers. Repeaters and base stations will feature coupling networks for interfacing with the existing telephone circuits. Frequency modulation (FM) and single sideband (SSB) modulation processes are analyzed in view of the special conditions associated with underground mining. Of primary importance is the tremendous electrical noise generated in an operating mine that could adversely affect communications quality. High noise coupled with high attenuation rate of near field signals forces the communication system to be inherently short range. Fortunately, near field signals can propagate over great distances on underground wires and cables. The framework for comparison is generated by presenting all factors that

By Robert R. Stein, Roy C. Bartholomae, William W. Aljoe

This Bureau of Mines report describes in detail the design and operation of a test apparatus for measuring the sound power levels of drills used by the mining industry. The two major components of the test apparatus are a computer-controlled automated drill test fixture (ADTF) and a large (45,000-ft3) reverberation chamber that houses the ADTF. Design specifications and performance capabilities of the ADTF and the reverberation room are given. Initial test results for three types of drills--a pneumatic percussion drill, a hydraulic percussion drill, and a pneumatic rotary drill--are given to illustrate the types of experiments that can be conducted with the test appartus.

By Kevin Connor

The mineral industry in Burundi was a minor contributor to the country's gross domestic product (GDP), which was estimated at just $1 billion for 19812. Coffee and tea continued as the Nation's major export commodities. Mineral exports consisted of small tonnages of wolframite, cassiterite, and baetnasite. Burundi's trade balance of payments situation worsened in 1981, with import payments more than double export revenues. Petroleum imports alone equaled 46% of the export revenue total. By year-end, the only indigenous fossil fuel source to have been found in Burundi was peat, which the Government had been attempting to develop to alleviate some of the petroleum import requirements. In June 1981 the Irish Peat Development Authority, Bord na Mona, signed a 4-year contract with the Burundian Government to supply technical staff for the ongoing peat project work there. Funding for the project was provided by the VS. Agency for International Development and the Government of Ireland. The new contract, which was an extension of ongoing peat research there, represented Burundi's increased awareness of the value of its large peat reserves for both energy and agricultural uses. At yearend, Burundi's Ministry of Public Works and Mines was does to selecting a contractor to study the feasibility of developing Burundi's phosphate deposits. The study would determine the potential for establishing fertilizer production facilities based on the country's phosphate reserves at Matongo-Bandaga, The study's specific objectives are to prove mineral reserve tonnage and grade, draw up mining and processing facility designs, estimate capital and production costs, and conduct a regional market and distribution survey. The cost of the study was estimated at slightly over $1 million, and it should take approximately 16 months to complete. The proposed project will mark the Burundian Government's first step in its plan to exploit on a large scale its natural mineral resources for advancing its agriculture-based economy. Burundi was dependent on imports, which are expensive to transport inland from coastal ports, to supply its domestic requirements for fertilizer. It was planned that part of the fertilizer production from the

Jan 1, 1983

By J. R. Welty

High-temperature thermodynamic data have, in recent years, become increasingly important for the extractive metallurgist. The extraction of metals from their ores previously was based on trial and error methods, involving hours of testing and often costly equipment fabrication. Using thermodynamic data it is frequently possible to predict the feasibility of a proposed metallurgical process as well as the optimum operating conditions for the process with reasonable accuracy. Such predictions can save consider-able tim~ and expense. Widespread use of thermodynamic analyses has been handicapped by lack of dependable experimental data. Investigators, notably K. K. Kelley (4)4. have devoted many years to determining and compiling such data. These investigators, although prolific in their production of thermodynamic values, have been unable to meet all the needs of industry and other branches of science. This becomes obvious when one considers the aeronautical and nuclear fields, in which previously unimportant, therefore uninvestigated, substances have become of prime importance.

Jan 1, 1962

By J. B. Gayle

Numerous investigators have studied the addition of inert4 substances to coking blends. Generally, the results have yielded trends applicable only to the particular coals and inerts studied. Recently, somewhat more general results were obtained for cokes produced from blends containing added inerts, using the sole-heated oven. The present investigation represents an extension of this work to include a wider range of inerts and to determine the applicability of the various conclusions to cokes produced with the Tuscaloosa oven. The results indicated that an increase in dry-coal charge density of 1 pound per cubic foot (p.c.f.) caused a corresponding change in the hardness (1/4-inch tumbler index) of Tuscaloosa oven cokes of 0.9 percentage points. This value compares favorably with the value of 0.7 determined previously for the sole-heated oven and Bureau of Mines-American Gas Association (BM-AGA) retort.

Jan 1, 1961

By R. V. Ramani

"Exposure to respirable contaminants in mine atmospheres has long posed a serious hazard to miners. The control of these hazards, some of which can have sudden and catastrophic effects and some others, slow and long enduring consequences, has been a major concern for labor, management and government alike. This concern has manifested itself in four primary mechanisms of control -- (1) regulatory control through minimum standard setting by the passage of mine health and safety laws, (2) engineering control through design and operation of 'mines according to the best recommended practices, (3) medical control through periodic physical examinations, wearing personal protection devices, etc., and (4) legal and social control through workmen's compensation laws for occupation related health deterioration:-The respirable contaminants in mine atmo¬spheres are toxic and explosive gases, toxic and explosive dusts, diesel exhaust particu¬lates, radon progeny, etc. Perhaps the most important of all these and the most widely occurring in mine atmospheres is respirable dust, an inevitable product of fragmentation, a unit operation fundamental to all mining operations. In fact; the-most serious health hazard for workers in the mining and minerals processing industries is still the exposure to respirable dust, and solutions to the problem of respirable dust disease remain to be found.The 1969 Coal Mine Health and Safety Act and its provisions for the respirable dust standards in underground coal mines are briefly reviewed. An overview of the research accomplishments in meeting the standards is presented. The current state of knowledge on the effectiveness of the standards and the new and emerging problems are discussed. A brief summary of the research programs of the Generic Technology Center on Respirable Dust is presented.In general, underground mines are becoming increasingly safe. The mine atmospheric environment is definitely improving * Professor and Head, Department of Mineral Engineering,-The Pennsylvania State University, University Park, PA for the better. Significant progress has been made in lowering the dust levels in mines. It is generally agreed that mines are less dusty today than they were a decade ago. However, as long as the risks of occupation-related diseases are not completely eliminated, vigilance can hardly be relaxed, and the search for engineering solutions must be intensified."

Jan 1, 1988

By Ray J. Holmquist

"INTRODUCTION The Copper King or Red River copper mine was examined on December 13, 1942, by the Bureau of Mines at the request of Richard Kelly of Santa Fe, N. Mex. The examination was made to determine whether the expenditure of funds for rehabilitation work necessary to make the workings accessible for examination would be warranted.As a favorable report was made, the workings of the Copper King mine were opened and sampled under the direction of the author. The portal of the Copper King adit was opened first. Considerable rehabilitation was necessary in the first 50 feet of the workings, but the remainder of the drifts and crosscuts were sufficiently open to permit surveying and sampling.An attempt was made to open the Waterbury atilt, which was reported to be about 30 feet east of the Copper King portal, and to crosscut the ore body nearly to its southern border. However, slide rock and mine dumps had completely obscured the portal of this adit, and no opening into it could be found or made.Work on the project was started on September 27 and vas completed on November 6, 1943."

Apr 1, 1947

Provide mine operators with a quick means of identifying the effect of cutting system changes on relative dustiness at the mine face, by developing an interactive computer program for drum-type coal mining machines. Approach A program which simultaneously evaluates machine parameters, coal seam parameters and mine operator-controlled parameters for their effects on relative dustiness has been developed for use on any minicomputer using BASIC computer language. How it works The interactive computer program allows mine operators to make one or more changes at a time to their cutting system to determine how these changes affect relative dustiness of the face. Using this program, mine operators can find the optimum cutting system configuration to minimize dust using their seam conditions and their equipment specifications. The mining machine variables include: number of vane bits, number of gage bits, number of starts, vane wrap, number of end ring lines, rpm, advance rate, ton/min, percentage of time spent cutting per shift, and airflow.

Jan 1, 1986

By Vijia K. Karra, John J. Sammarco, Robert Paddock, Edward F. Fries

Workers in hazardous environments such as mining are constantly exposed to the health and safety hazards of dynamic and unpredictable conditions. One approach to enable them to manage these hazards is to provide them with situational awareness: real-time data (environ-mental, physiological, and physical location data) obtained from wireless, wearable, smart sensor technologies deployed at the work area. The scope of this approach is limited to managing the hazards of the immediate work area for prevention purposes; it does not include technologies needed after a disaster. Three critical technologies emerge and converge to support this technical approach: smart-wearable sensors, wireless sensor networks, and low-power embedded computing. The major focus of this report is on smart sensors and wireless sensor networks. Wireless networks form the infrastructure to support the realization of situational awareness; therefore, there is a significant focus on wireless networks. Lastly, the “Future Research” section pulls together the three critical technologies by proposing applications that are relevant to mining. The applications are injured miner (person-down) detection; a wireless, wearable remote viewer; and an ultrawide band smart environment that enables localization and tracking of humans and resources. The smart environment could provide location data, physiological data, and communications (video, photos, graphical images, audio, and text messages).

Jan 4, 2007

By D. R. Douslin

This report describes an inclined-piston pressure gage that operates from a zero-pressure datum level. The gage is adaptable to accurate vapor-pressure measurements in the low and intermediate pressure range, 0.01 to 40 mm (mercury). Residual friction in the oil-lubricated piston-cylinder combination is eliminated by a unique oscillatory method that is free of end thrust on the piston and allows the full sensitivity of the gage to be realized. The axial component of the weight-to-area ratio of the piston is determined by measuring the angle of inclination with a goniometer that can be read to 1 sec. Accuracy of the gage proper is estimated to range from 0.001 to 0.012 mm from lower to upper pressure limits. Its highest practical sensitivity is about 0.0005 mm. As a test, the vapor pressures of ice and water were measured in the range -30° to +20° C.

Jan 1, 1963

By A. R. Rule

Research was conducted by the Bureau of Mines to develop a process for utilization of Idaho kyanite. A continuous gravity-flotation separation process was applied successfully to recover kyanite-group minerals from an Idaho ore containing about 21 percent combined kyanite, andalusite, and sillimanite. Dry magnetic separation of the concentrate resulted in a product containing about 90 percent kyanite at a recovery of 63 percent of the kyanite-group minerals in the ore, Alumina and silica analyses were within the range generally accepted for conversion to mullite, and the finished products had a pyrometric cone equivalent of more than 38. A recovered garnet coproduct may be of commercial value.

Jan 1, 1973

By J. E. Zeilinger

This Bureau of Mines report describes the preparation characteristics of three samples collected from the Kidney seam, in the Northern Field of the anthracite region. Removal of the sink 1.70 specific gravity material from the samples collected would result in greatly reduced ash contents at yields in excess of 90 percent. The Kidney seam, in the locations sampled, proved to be a low-ash anthracite containing an unusually high percentage of float 1.45 specific gravity material.

Jan 1, 1970

By Richard H. Singleton

Native asphalt was produced in 1978-79 by six companies in four States. Leading States were Texas and Utah. Output in-creased 37% in 1978 to 1.7 million tons and decreased 5% in 1979 to 1.6 million tons while value increased 39% in 1978 to $19.3 million and 33% in 1979 to $25.6 million. Bituminous limestone was produced by Whites Uvalde Mines and by Uvalde Rock Asphalt Co. in Uvalde County, Tex.; by Southern Stone Co. in Colbert. Ala.; and by Barton County Rock Asphalt Co. in Barton County, Mo. The product was used mainly in street and road repair. Gilsonite was produced by American Gilsonite Co. in Uinta County, Utah, and by Ziegler Chemical and Mineral Corp. in Weber County, Utah. This material was used for purposes other than road repair.

Jan 1, 1980

By F. L. Wideman

Materials handled at metal and non-metal mines in the United States increased 10 percent compared with those of 1965 as a result of expansions in output at existing mines and development of others to meet increasing demands for mineral products. The tonnage of commercial materials mined or quarried increased as did the quantity of waste handled. Crude material from which metal or nonmetal products were derived comprised 71 percent (75 percent in 1964) of the total materials handled. Great strides were made in mining technology and there were indications that, in the future, earth moving by the mining industry will involve materials-handling systems of increasing size and complexity. Materials Handled.-Output of ore and waste at metal and nonmetal mines and quarries in the United States in 1966 totaled 3,518 million tons (3.213 million tons in 1965). The quantity of materials handled has increased at an average annual rate of 5 percent since 1962. Ore production increased 4 percent over that of 1965, also comparable to the average annual rate of increase in the last 5 years. Waste removal in 1966 increased 25 percent over that of the previous year.

Jan 1, 1967

By B. Dimitriades

Experimental work has been done to refine and to confirm an analytical procedure by which gas-liquid chromatographic (GLC) spectra are interpreted from retention time data alone. The rationale of this spectra interpretation technique involves whether or not a given peak invariably represents the same component or component mixture; if not, what factors influence changes in peak identifications. To answer these questions, peak-identification procedures, based mainly on the use of subtractive columns, were developed and applied to interpret GLC spectra of several exhaust (and fuel) samples.

Jan 1, 1972

By Paul T. Allsman

THIS CHAPTER reviews the highlights of developments in mining technology during 1956 and presents a special report on the design of mine openings in stable ground. This special report is presented each year in an endeavor to stimulate use of the scientific approach to the solution of problems related to mining technology. Assuming that the literature on mining technology reflects trends in mining, it appears that two areas of activity were given most attention in 1956. One was research on mining technology,4 and the other was improvement of transportation, particularly trackless transportation, both at surface and underground mines.

Jan 1, 1958

Utilize innovative processing technology to prepare high-purity, ultrafine advanced ceramic powders with little or no contamination occurring during the milling process. Advanced ceramic materials made from these powders could substitute for high-temperature alloys containing critical materials such as chromium, cobalt, and nickel. Approach Modify and evaluate the Bureau's turbomill, developed earlier to grind a variety of ceramic raw materials (clay, mica, and talc), as a milling or size-reduction technique for hard and abrasive advanced ceramic powders, such as silicon carbide. Background Powders for producing ceramic materials, such as silicon carbide. silicon nitride, alumina, and zirconia, which arc being considered for use in severe applications requiring high-temperature and/or corrosion resistance, are very difficult to reduce to fine sizes for processing into finished parts. Traditional techniques of particle size reduction, such as ball milling and jet milling, are very energy intensive and/or slow. These traditional techniques often produce materials that have a nonuniform particle size distribution and are contaminated by the milling media or container.

Jan 1, 1989

By Robert J. Anderson

"Introductory Statement.In founding any kind of castings, even with the best practice, scrap castings are produced because of rejections for certain defects. Casting los¬ses are a serious source of financial loss in iron and steel foundry practice as well as, in brass and bronze, but they are particularly serious in aluminum foundry work because of the high value of aluminum. The indications are that in many aluminum foundries in the United States, the casting losses are at times high, and in some plants they are entirely too high when compared with average practice. Of course, defective castings have a residual value for remelting, but if much machine work has been done on a casting before it is scraped, the labor costs alone may exceed the value of the metal and even that of the rough casting.In a foundry, the monetary losses incurred through the production of waster castings can be ascertained from calculations based upon adequate scrap-loss reports. Such reports, when properly kept and interpreted are a valuable aid in finding foundry costs, but they are primarily useful in diagnosing the causes for casting losses. Many aluminum foundries in the United States do not keep adequate records of strap losses; as a result the causes for defective castings can not be traced, nor preventative measures adopted. However, some of the large aluminum foundries keep excellent records, and it has been found that these involve little extra expense for clerical work. If a foundry man will study his daily production of defective and waster castings, he will be able to trace the causes or losses and then make such corrections in his plant practice as will effect a considerable reduction in these losses -- as much as 50.0 per tent in some foundries. If all the present casting losses of the United States could be reduced 50.0 per cent, by eliminating only the readily preventable defectives, a saving of several million dollars would accrue. In the aluminum-foundry industry alone, the saving would amount to about $600,000."

Apr 1, 1920