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By Mukhopadhaya K. K, Cory A. H

The concept of using travelling magnetic fields created by linear motors was stimulated by Laithwaite who advanced ideas on motors with shaded poles (Laithwaite, 1968), rack and pinion motors (Laithwaite, 1970) as well as low speed, brushless motors and three dimensional motors (Laithwaite, 1973a and 1973b).Sudan (1963) and Sundberg (1969) had applied the concept to metallurgical processes. However, the use of travelling magnetic fields has not been used widely to produce conditions for the separation of magnetic from non-magnetic minera1s or even magnetic materials from non-magnetic materials, although some attempts were made by McCarthy (1922), Davis (1934), Dean, Gottschalk and Davis (1934) and Gottschalk (1934).Laithwaite (1973, a) while working with linear motors made suggestions for designing separators and in the work described here, the observations of Laithwaite and others are extended to determine the characteristics of the motor with a view to using it as a magnetic separator.

Jan 1, 1980

By M. Foguenne, A. van Lierde, P. Henry

Leaching experiments were carried out on a spent catalyst sample with a honeycomb structure, containing 47.5% Ti, 5.8% Mo, 2.7% Si, 2 035 ppm As, 52 ppm Pb and 8.8 ppm Hg. More than 93% of the Mo and As was removed by direct alkaline leaching after grinding to 80% -36 micrometres. The residue contained 0.3% Mo and 60 ppm As. To obtain a TiO2 matrix with 30 ppm As, acid leaching at controlled pH with 90 kg/t Al scrap was followed by oxidising alkaline leaching. Treatment of the direct alkaline leach solution or of the mixed solutions from the two-stage process involved two successive operations: purification by neutralisation with Al(OH)3 addition to raise the Al concentration to 4 g/l, and ion exchange on Amberlite IRA 94 S resin. Whatever the type of solution treated, elution with 200 g/l NH4OH solution gave an eluate of very high purity containing 164 g/l Mo, less than 70 mg/l V and less than 2 mg/l As

Jun 19, 1905

By Nicholas Chlumecky

One of the oldest mine supports in use today is timber cribbing. In many mining operations material, installation and maintenance costs for timber cribbings are substantial. Their performance characteristics also add to mining costs. During the 1970'6, the U.S. Bureau of Mines recognized many of the deficiencies of timber cribbing and very successfully initiated the development of steel-fiber- reinforced (SFR) concrete blocks. Since the early 1980's this SFR concrete cribbing has been manufactured as a high quality product which has found increasing acceptance by mine operators. The rapid acceptance of the SFR concrete block cribbing has proven that its use is eliminating many of the deficiencies of timber cribbing while providing superior load carrying capability. The use of SPR concrete blocks to build the cribbing is based on the same principle as wood. That is, stacking longitudinal, rectangular blocks in layers in a crisscross manner. The blocks are positioned at right angles to the blocks of the layer below. With this situation, the possibility of misalignment exists when the concrete blocks at the base are not placed exactly parallel or when the blocks of the base are subject to unequal settlement. Such misalignments creates localized, high stress areas which reduces the load capacity of the cribbing made from SFR concrete blocks. Recognizing the problem of misalignment, the Underground Supports Division of Commercial Shearing, Inc., conceived a circular, one-piece, steel-fiber-reinforced concrete cribbing which is being marketed under the name - Donut Cribbing. This concept eliminates the possibility of misalignment and provides 100% bearing between layers of stacked cribbing as well as other advantages. The purpose of this paper is to discuss the performance characteristics, installation speed and economical factors of each of the three cribbing types -- timber cribbing, SFR concrete block cribbing and SFR concrete Donut Cribbing.

Jan 1, 1986

By R. Venugopal, T. C. Rao, N. Suresh

Experiments were carried out using the cyclone to treat coal in the size range -2.0+0 mm. The diameters of the cyclone outlets (vortex finder and spigot) were varied to study their effects on cyclone performance. The cyclone products were deslimed over a screen with an aperture of 0.075 mm. The performance of the separator was studied for washing coarse coal (-2.0+0.075 mm) and fines (-0.075 mm). Performance curves were plotted for the separation of -2.0+0.075 mm coal. The concept of a generalised distribution curve was adopted to predict cyclone performance. A mathematical representation was derived from the generalised distribution curve. The specific gravity of separation for individual size fractions showed a decreasing trend with decreasing particle size down to 0.85 mm, beyond which a reverse trend was noted. It was also found that the fine size fraction (-0.075 mm) does not separate on the basis of size or specific gravity but follows the water distribution

Apr 1, 1995

By Terry J. Close

A mineral resource survey of the 236-mil (611-km2) Hyalite-Porcupine-Buffalo Horn wilderness study area (RARE 11 Areas No. 1-155 G, Gallatin Divide; and H, Hyalite) between the Gallatin and Yellowstone rivers in Montana, indicates there are phosphate rock and petrified wood resources (fig. 1). The area also has some potential for oil, gas, and geothermal resources. Stone and alluvium are abundant but appear to have little potential for development because other sources are available nearer to markets.

Jan 1, 1981

By Fredrick L. Johnson

The Jerry Peak, Jerry Peak West, and Boulder Creep: Wilderness Study Areas contain no identified mineral resources. Two workings, a 20-ft-long adit and a pit, were found in Paleozoic, brecciated, limonitic jasperoid in the east part of the Jerry Peak Wilderness Study Area (WSA), but no significant metallic mineral values were noted. Lenses and pods of quartz containing copper minerals occur in Paleozoic sedimentary rocks 1/2 mi north of the Jerry Peak West WSA. Similar rocks crop out along Pine Creep: in that study area but no copper-bearing quartz lenses were found.

Jan 1, 1984

By Steven W. Schmauch

The Farlin Creek study area encompasses 610 acres managed by the Bureau of Land Management in Beaverhead County, Montana. A mineral survey was conducted by the U.S. Bureau of Mines and U.S. Geological Survey in 1984. Bureau of Mines personnel reviewed literature and county mining records, and examined prospects or mineralized areas to determine its mineral potential. Geological Survey personnel evaluated the area by geochemical sampling and geophysical surveys. The study area is included in the Mount Baldy mining district. Nearby mineralized Quartz veins or tactite bodies apparently do not extend into or exist within the study area. No significant gold or economic detrital minerals were found in samples from streams draining the area. All of the study area is leased for oil and gas.

Jan 1, 1985

By Robert Stefanko

This report abstracts project work performed for the USBM Grant No. GO-133077 during the period 19 June 1973 to 15 October 1974. Five reports have been separately produced and are as follows: 1. Mine Electrical Systems Evaluation - Cable Splicing, 2. Mine Electrical Systems Evaluation - Explosion-Proofing of Mine Containers, 3. Mine Electrical Systems Evaluation - Transient Analysis, 4. Mine Electrical Systems Evaluation - Mine Power System Performance, and 5. Mine Electrical Systems Evaluation - Model Coal Mine Electrical System Specifications. Abstracts of each comprise the balance of this executive summary, and 50 copies of each volume have been forwarded to the USBM under the terms of the grant agreement.

Jan 1, 1974

This report summarizes the results of the Narragansett Win Projec't's activities during the U.S. Bureau of Mines (BOM) Phase 1, which was transitional from and which followed the National Science Foundation (NSF) Phase which initiated the investigation of New England's potential roil resource. The 960 sq. mile basin is structural and topographic lowland containing 12,000 to 20,000 ft. of terrigenous clastic sediments of late Pennsylvanian age, and which rests on an upper Precambrian and Cambrian basement. The Rhode Island Formation, which is the coal-bearing unit, comprising the bulk of the Pennsylvanian rocks consists, in order of decreasing abundance, of sandstone, conglomerate, silts tone, shale, and coal. In the NSF Phase, 24 drill-holes yielded 17,900 ft, of core; in the BOM Phase I study, 4 drillholes yielded 2,100 ft. of core. Anthracite and semi-anthracite was encountered in beds Up to 30 ft. thick in widely spaced parts of the Basin. The coal, typically very low in sulfur, and a high ash anthracite, won mined in substantial volumes from 1808 to 1959 from shaft and open lit in Portsmouth and Cranston, R.I., and in lesser volumes in Mansfield, Mass. Currently coal is now being mined in Plainville, Mass. as a fuel in the manufacturing of light-weight aggregate from the same quarry that serves as the source of the rock being processed. The structurally complex Narragansett Basin is now known to have a greater extent than earlier since recent drilling by others (Chapter 2) has confirmed our interpretation that the Basin extended offshore south A Boston. The, Basin also extends into Rhode Island Sound to the south. The geological structure is more complex in the southern part of the Basin than in the northern part. Three episodes of folding have been documented on Aquidneck Island and four episodes of faulting have been demonstrated for the Basin as a whole. Relatively less well exposed rock in the northern part of the Basin, increases the difficulty of recognizing and correlating structural episodes in the northern part of the Basin. The Basin his hewn subdivided into six structural domains which appear to have distinctive structural, metamorphic, paleontological and sedimentological differences that mw assist in isolating important events in the evolution of the Basin and its component parts. The tentative structural model recently developed in POP Phase I has important implications for exploration and mining. In the first and second folding stages the coal is mobilized and thickened in the crests and troughs of folds whose axes are horizontal to subhorizontal. While conventional coal exploration and mining methods are not applicable, great thickening in the crests and troughs of large scale structures, which can he defined by geology, geophysics and drilling, may provide compensating advantages. Bedrock over most of the Basin is 0-50 ft., but thicknesses of glacial deposits up to 150 ft. are present locally. Pro-Pleistocene topographic trends are controlled by structure and rock hardness; Pleistocene deposits aligned to the S. F. are superimposed on earlier trends. The southern part of the Basin is mainly dominated by high grade Barrovian metamorphism and plutonism of Permian age, related to the Alleghanian Orogeny. About 300 sq. miles of the 960 sq. mile Basin has been affected. The remaining 660 sq. miles, in the chlorite and subchlorite zones of metamorphism are compatible with the presence of high quality anthracite and semi-anthracite. Illite crystallinity studies begun in the NSF Phase, have been carried out in the BOM Phase l with important results. About ME of the northern Basin is now known to be in the diagenetic (unmetamorphosed) or subchlorite zone and the remainder in the chlorite zone of metamorphism. Mite studies, probably best recording temperature effects, show a generally progressive increase from the NW corner of the Basin near Plainville, Mass. toward the south and southeast. Reflectivity and coal petrography studies, probably best recording pressure and effects related to shearing, indicate a generally opposite pattern. Thus these methods provide powerful tools for the ultimate solution of problems important to coal exploration for coals of higher combustible volatile content and exploitation of these. Due to the complex nature of the coal, chemical data may not he easily used to determine rank. The coals have been tectonically deformed and mineralized. This deformation plus thermal metamorphism have altered the coals, in some cases by producing natural coke. Brecciated coal is often coated with a secondary depositional carbon. The coals' hydroscopic nature and high ash contents are due to the deformed nature of the coal and the presence of this secondary carbon. The stratigraphy and sedimentology of the coal-bearing Rhode Island Formation is similar to described alluvial fan deposits. The non-geological studies al-low three conclusions to be made: 1. A substantial number of areas have been identified in the Narragansett Basin in which mining could be carried out without undue difficulty from a land use point of view. 2. Substantially more than two hundred instances of past or current- mining activities have been identified in the Basin. Many of those are in areas defined as geologically interesting, and may be advantageous From the point of view of future exploration. 3. The map synthesis technique developed for this contract is successful and may easily be adapted to future exploration in its current form and also in its expandable form dealing with unit measurements of one-tenth mile. We recommend that BOM Phase 2 exploration should accomplish the intent of the Congressional language in House Report No. 95-1251, to continue a substantial drilling and geophysics program: "The Committee expects the Bureau to continue studies involved in ascertaining the extent and quality of low sulfur coal reserves in the Narragansett Basin in New England including necessary drilling and geophysical studies. The knowledge of the extent of such deposits is of great importance to this 'energy pour' area".

Jan 1, 1979

By Ignaz Lichtig

[IN CONNECTION with its work on the conversion of coal to liquid cud gaseous fuels,3 the Bureau of Mines has always striven to keep informed of developments in this and related fields so that unnecessary duplication of effort could be prevented and so that useful ideas, presented in scientific and technical literature, could be evaluated as quickly as possible. Thus the E has compiled expensive literature and patent abstracts on the Fischer-Tropsch synthesis4 and hydrogenation d e venation of coal at elevated h temperatures and pressures.5 6 This publication differs from the references just given in that it covers patent applications, which may or may not have been approved for issuance as a patent, and also includes later material. The patent literature is, of courses, a valuable source for new ideas. German patent, have been particularly useful in this field because both processes for the complete conversion of coal to fluid fuels originated in Germany and were thoroughly investigated there because of the shortage or of indigenous fluid fuels. Among the German literature relating to these processes are patent applications. In contrast to the United States, Germany has a system in which applications are published before the final patents are issued. This arrangement permits the public to view all the applications and not just those for which a patent was granted as is done in the U.S. system. When main of the invention are judged not patentable by the German Patent Office, such documents nevertheless may contain useful ideas for scientists and engineers.]

Jan 1, 1961

By John C. Machisak

THIS PUBLICATION presents injury experience and employment data for the nonmetal mining industry in the United States for 1960. Data for the mines and mills are presented separately, as shown in the list of tables. The Bureau of Mines is authorized to send questionnaires to the nonmetal mining industry for their voluntary submission of injury and employment data. As the information submitted contributes largely to the promotion of safety in the industry, special effort has been made to ma e these questionnaires as complete as possible.

Jan 1, 1963

By John C. Machisak

THIS PUBLICATION presents injury experience and employment data for the nonmetal mining industry in the United States for 1960. Data for the mines and mills are presented separately, as shown in the list of tables. The Bureau of Mines is authorized to send questionnaires to the nonmetal mining industry for their voluntary submission of injury and employment data. As the information submitted contributes largely to the promotion of safety in the industry, special effort has been made to make these questionnaires as complete as possible.

Jan 1, 1963

An underground mine disaster is an accident of major proportions that takes a significant toll in human lives. A disaster usually disrupts the normal functioning of a mine and may result in entrapment of miners whose normal egress from the mine is cut off. A disaster often necessitates a rescue operation and a means of keeping the trapped miners alive while they await rescue. Explosion, fire, inundation of water or toxic gases, and collapse of a major portion of a mine are among the causes of mine disasters. Miners threatened by such an occurence must either bring the situation under control (e.g., by extinguishing a fire) or remove themselves from the danger. If control is unsuccessful, they must retreat to a place of safety. Four different activities may be involved: evacuation, escape, survival, and rescue. Evacuation is the orderly exit of people from the mine using previously identified escapeways and following a previously determined evacuation plan. Miners whose normal evacuation routes are blocked may be able to find alternative exit routes and escape by their own efforts. For those who cannot, the issue becomes survival while waiting to be rescued. The survival period may last for many days while rescue efforts are mounted from outside the mine.

Jan 1, 1981

By T. F. Anstett

The Bureau of Mines estimated the potential availability of tungsten from 57 mines and deposits in 19 market economy countries. The tungsten resources of China and the U.S.S.R. were also estimated. This resulted from an evaluation of tonnage-cost relationships indicating the quantity of tungsten available as ammonium paratungstate (APT), artificial and natural scheelite, and ferrotungsten at various average total costs of production including 0- and 15-pct rates of return on invested capital. The evaluated deposits contain 1.2 million metric tons (t) of recoverable WO3, of which approximately 52,000 t of AEYT can be produced at the January 1983 market price of $5.37/lb, 89,000 t of natural and artificial scheelite at a market price of $3.63/lb, and 1,700 t of ferrotungsten at $5.61/lb of tungsten. An annual availability analysis indicates that by the early 1990's new deposit discoveries, development of known prospects, or expansions of producing mines will be necessary to meet projected tungsten demand.

Jan 1, 1985

Research personnel from the Bureau of Mines, a representative of the Mine Safety and Health Administration, and research contractors for the Bureau of Mines met with other Government and industry representatives at three seminar locations in December 1980 to discuss the findings and products of Bureau research on mine safety training. The research program is aimed at providing assistance to the mining community in its efforts to reduce industrial-type, human-error accidents through research establishing performance based methods and media for employee training. Research emphasis is directed toward development of baseline materials and instructional models; development of methods for structuring and evaluating health and safety, supervisory, and occupational training; and the continued investigation and application of current learning and simulation technology that could significantly enhance the effectiveness of training opportunities.

Jan 1, 1981

By C. Ogasawara

This document describes the direction and progress of the Bureau of Mines Oil Shale Mining Environmental Research Program as of January 31, 1979. It is aimed at focusing the Bureau's role in environmental research supporting oil shale development with respect to the activities of other involved government agencies and private industry. Environmental considerations in oil shale extraction, such as ecological disturbances, health and safety hazards, waste management, and socioeconomic impacts, are discussed along with the type of research known to be planned by organizations to ameliorate these problems.

Jan 1, 1979

By Choon Kooi Quan

Water availability is essential for mining and minerals processing. To provide government and industry with recent data for water use planning and management, the Bureau of Mines canvassed a number of U.S. producers of nonfuel minerals to determine their water use in 1984. Data were analyzed and compared with previously published data in order to examine historical trends in water utilization in the nonfuel minerals industry and to estimate water requirements in the year 2000. Total water use in the domestic nonfuel minerals industry during 1984 was estimated at 2,267 billion gal, of which 571 billion gal was new water and 1,696 billion gal recirculated water. The largest users of water were the phosphate rock, iron ore, copper, sand and gravel, and crushed stone industries, together accounting for almost 90% of total used. More than one-half of all water was used in Florida, Michigan, and Minnesota. In the year 2000, total water use will amount to an estimated 2,679 billion gal, of which 810 billion gal will be new water and 1,869 billion gal recirculated water. Most of this water would be used in producing the foregoing suite of minerals,

Jan 1, 1988

By William E. Sopper

Heat-dried municipal sludge was applied to a barren burned anthracite refuse bank in 1974. Sludge was applied at rates of 0, 40, 75, and 150 dry metric tons per hectare" Ten species of trees were planted and five species of grasses and legumes were seeded for evaluation. One plot was also irrigated with sewage effluent. The 150 t/ha sludge application rate produced the best overall herbaceous vegetation growth response. The 40 and 75 t/ha sludge application rates produced the best tree seedling growth response. Foliar analyses for trace metals indicated no phytotoxity problems. Analyses of leachate water at the three-foot soil depth indicated that the sludge applications did not impair water quality. Results of the study indicate that treated municipal sludge can be used to revegetate land disturbed by mining activities without adverse effects on the vegetation or water quality.

Jan 1, 1978

By John S. Ball

[A system of analysis for sulfur groups in petroleum distillates has been developed as one phase of the Bureau-of Mines investigation of the more economic utilization of the so-called "black oils" of Wyoming. This problem is being studied by the Bureau of Mines under a cooperative agreement with the University of Wyoming at the Bureau's Petroleum Experiment Station , Laramie, Wyo. Wyoming black oils have high sulfur and asphalt content and usually yield only small percentages of straight-run gasoline. A more detailed description of the properties of black oils has been given in a previous publication (3)3/. The preparation and properties of asphalts from those oils have been described (1, 2), and the effect of thermal cracking and the use of ordinary methods of treating wore discussed in one Bureau publication (4), Although these studies gave considerable insight into the properties and characteristics of black- oils; it was thought t that a more fundamental attack would assist-materially in, the problem of sulfur removal.]

Jan 1, 1941

By John S. Ball

[A system of analysis for sulfur groups in petroleum distillates has been developed as one phase of the Bureau-of Nines investigation of the more economic utilization of the so-called "black oils" of Wyoming,. This problem is being studied by the Bureau of Nines under a cooperative agreement with the University of Wyoming at the Bureau's Petroleum Experiment Station, Laramie, Wyo. Wyoming black oils have high sulfur and asphalt content and usually yield only small percentages of straight-run gasoline. A more detailed description of the properties of black oilshas been given in a previous publication (3)3/. The preparation and properties of asphalts from those oils have been described (1, 2), end the effect of thermal cracking and the use of ordinary methods of treating wore discussed in one Bureau publication (4), Although these studies gave considerable insight into the properties and characteristics of black oil, it was thought t that a more fundamental attack would assist materially in the problem of sulfur removal.]

Jan 1, 1941