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By R. Q. Shotts

Factors of geological structure and occurrence of coalbeds, plus the resulting mining conditions, have required more care in preparing coals in Alabama than in most other districts almost since mining Alabama coals began. For this reason, literature on these coals may be interesting to those in areas where prime coals have been mined out, and thinner and less regular beds must now be exploited. This literature review has been arranged in order of subject matter. Some references have been listed more than once, but each separate review is limited to the material pertaining to the subject matter being discussed. For those seeking specific information, the authors have indicated which items repeat material and which items are most complete or specific. Geology, preparation, and carbonization of coal have been reviewed the most frequently.

Jan 1, 1963

By A. G. Starliper, H. Kenworthy

A procedure was developed for the separation of lead and sulfur in industrial concentrates of galena by a combination of chlorination and fused - salt electrolysis . Galena could not be satisfactorily electrolyzed in the various media tried ; however , when it was treated with chlorine the resulting lead chloride could be effectively separated electrically into lead and chlorine . An apparatus was designed and constructed to chlorinate galena and to volatilize simultaneously most of the chloridized impurities . By electrolyzing the chlorinated concentrate , a high percentage of lead was recovered . Anodic chlorine was drawn from the cell and was used to chlorinate new feed . In many runs , the recovered metal analyzed from 99.8 to 99.9 percent lead . Lead was also distributed as a chloride in the bath , and a small portion was in the volatile fraction produced during the chlorination step . During a tinuous operation , only 0.1 percent of the total lead was discarded ; 99.9 percent was accounted for in the metal , electrolytic bath , and washed or leached chlorination condensate which was essentially lead chloride . About 95 percent of the sulfur from the galena was recovered as a byproduct of over 90 - percent grade .

Jan 1, 1964

Development of automatic fire protection systems for large, mobile mine haulage equipment was initiated under Department of Interior's Bureau of Mines-FMC Corp. contract H0122053, "Improved Sensors and Fire Control Systems for Mining Equipment June 1972 to May 1973." After successfully designing and mock-up testing an effective economical automatic fire protection system, and after having demonstrated that the system could extinguish controlled fires on 100-ton capacity haulage trucks, USBM-FMC contract 110232059 was issued in June, 1973, to conduct further development and validation testing. This report documents technical progress and activity under the latter contract. Figure 1 shows areas of the two haulage trucks that were protected by the automatic fire protection systems tested during this program. Figures 2 and 3 are composites showing hardware and schematic diagrams of the systems tested.

Jan 1, 1974

By R. Q. Shotts

Factors of geological structure and occurrence of coalbeds, plus the resulting mining conditions, have required more care in preparing coals in Alabama than in most other districts almost since mining Alabama coals began. For this reason, literature on these coals may be interesting to those in areas where prime coals have been mined out, and thinner and less regular beds must now be exploited. This literature review has been arranged in order of subject matter. Some references have been listed more than once, but each separate review is limited to the material pertaining to the subject matter being discussed. For those seeking specific information, the authors have indicated which items repeat material and which items are most complete or specific. Geology, preparation, and carbonization of coal have been reviewed the most frequently.

Jan 1, 1963

By Lloyd A. Morley, Alan M. Christman

1. Anonymous. "Getting Down to Earth," booklet 25T, James G. Biddle Co, Plymouth Meeting, Pa. (1970) pp. 1-48. 2. Anonymous. "Megger Ground Tester, Special Instructions," booklet 25-J-1, James G. Biddle Co, Plymouth Meeting, Pa. (1961) pp. 1-16. 3. AIEE Committee. "Application Guide on Methods of Substation Ground¬ing," AIEE Transactions on Power Apparatus and Systems (April 1954) pp. 271-277. 4. AIEE Committee. "Voltage Gradients Through the Ground Under Fault Conditions," AIEE Transactions on Power Apparatus and Systems (October 1958) pp. 669-692. 5. American Standards Association. "American Standard Safety Rules for Installing and Using Electrical Equipment in and about Coal Mines," U. S. Bureau of Mines Information Circular 8227 (1964). 6. Armstrong, H. R. "Grounding Electrode Characteristics from Model Tests," AIEE Transactions on Power Apparatus and Systems (December 1953) pp. 1301-1306. 7. Beck, Edward. Lightning Protection for Electric Systems, McGraw¬Hill, New York (1954) pp. 281-295. 8. Bellaschi, P. L. "Impulse and 60 Cycle Characteristics of Driven Grounds," AIEE Transactions (March 1941) pp. 123-128. 9. Bellaschi, P. L. "Lightning Strokes in Field and Laboratory," Elec¬trical Engineering, Vol. 58 (November 1939) pp. 466-468. 10. Bellaschi, P. L., Armington, R. E., and Snowden, A. E. "Impulse and 60 Cycle Characteristics of Driven Grounds-II," AIEE Tran¬sactions (1942) pp. 349-363. 11. Bewley, L. V. "Theory and Tests of the Counterpoise," AIEE Transac¬tions (August 1934) pp. 1163-1172. 12. Brereton, D. S. and Hickok, H. N. "System Neutral Grounding for Chemical Plant Power Systems," AIEE Transactions on Applica¬tions and Industry (November 1955) p. 315. 13. Bruce, C. E. R. and Golde, R. H. "The Lightning Discharge," Journal of the Institute of Electrical Engineers, London, Vol. 88 (December 1941) pp. 487-505.

Jan 1, 1976

By George A. Savanick

This paper reviews advances in the art of borehole (slurry) mining made by the Bureau of Mines from 1974 to 1980. The design of a proto-type borehole-mining tool (BMT) developed by the Bureau of Mines is pre-sented along with production data, reclamation data, and an application of the BMT to the mining of coal, uraniferous sandstone, oil sands, and phosphate ore. The BMT was first used near Wilkeson, WA, where steeply pitching metallurgical coal was mined at 8 st/h from a depth of 25 to 75 ft. Next, 940 st of uraniferous sandstone was mined at 8 st/h from a depth of 75 to 100 ft in Natrona County, WY. One thousand short tons of oil sands was mined in Kern County, CA, at the rate of 14 st/h from a depth of 110 to 150 ft in 1979. Most recently, 1,700 st of phosphate ore was produced at 25 st/h from deep (230-to 250-ft) deposits in St. Johns County, FL. Progressive improvements were made in the borehole mining technique. These include the use of the hydrostatic head of a water-filled borehole for roof support, and the development of methods to survey and backfill mined-out cavities.

Jan 1, 1987

By Lester J. Crow

This study advances the use of elemental sulfur in structural materials by demonstrating its value in bonding high-strength, well-graded basalt aggregates to form sulfur-basalt concretes. Sulfur is an excellent bonding agent, and the strength of a thermoplastic sulfur-aggregate mixture depends, to a large degree, on the strength and grain-size distribution of the aggregate used. A 3-cubic-foot, electrically powered mixer with heat applied to the barrel was used to mix the sulfur and aggregate. Sulfur content of several mixtures was varied to obtain the best workability with a minimum of sulfur in excess of that necessary to fill the voids. The average grain sizes and grain-size distributions were also varied to determine their effects on strength. Unconfined compression tests of forty-five 6-by l2-inch cylinders yielded average strendths of 3,348 psi to 10,398 psi. The highest strength single cylinder was 10,717 psi. The cylinders were tested from 24 hours to 6 days after pouring; after 24 hours the rise in strength was very slight. From the results obtained it appears that sulfur can be a useful construction material. An evaluation was made of a high-vacuum application for sulfur concrete. Sulfur has a high vapor pressure at elevated temperatures, 50° to 100° C; consequently, significant losses by sublimation can be expected. At lower temperatures the losses are not significant; however, this factor will limit its use at a higher temperature.

Jan 1, 1970

By Donald W. Mitchell

Studies were made in the Bureau of Mines Experimental coal mine to evaluate the effectiveness of a few extinguishing agents and techniques for controlling a fire on a simulated mining machine. The investigation showed that water containing an alkali-metal salt or a surface-active (wetting) agent was more effective than water alone. For close attack, fog applications was the most effective technique studied; high rates of agent application controlled the fire more quickly than low rates. The ability to control the fire increased as the distance of attack decreased. Dry powders controlled the fire when applied by shovel but not when applied airborne by rock-dust distributor or by hand fire extinguishers. Dry alkali-metal salt powders (potassium and sodium bicarbonates and sodium tetraborate) quenched the fire more readily than limestone dust. In each instance the finer powder, the greater its effectiveness. In an open ventilated entry, smoke and hot gases backed against the air currents. An airspeed of 230 feet per minute was required to permit approach to within 10 feet of the fire. At lower airspeeds, approach could be made by extending the brattice across the bottom two-thirds of the entry, by pushing the smoke ahead with water sprays, or by discharging dust from a rock-dust distributor. In a dead-end entry, the fire was approached to within 30 feet by coursing fresh air along an airtight line brattice; however, it was safer, easier, and less time-consuming to attack the fire from a fresh-air base 100 feet away with a solid stream or by high-expansion foam; the latter method was more effective.

Jan 1, 1961

The principle activities of the Explosives Research Laboratory from July 1, 1961 to June 30, 1962, are described briefly in part 1. Part 2 gives short abstracts of publications that appeared during fiscal year 1962; in general, the research reported in these publications antedates the report period. Part 3 gives the results of an investigation which, although too limited to warrant separate publication, merits presentation in some detail because of current interest in ammonium nitrate-fuel oil compositions.

Jan 1, 1964

By F. G. Scott

This document is a proposed program plan for mining environmental research to be conducted by the U.S. Bureau of Mines in support of industrial oil shale mining and processing. This program plan is one of three research alternatives being considered by the Bureau, each based on a different level of anticipated funding. This report documents the low funding level program plan.

Jan 1, 1980

By Lawrence K. Requa

The property being worked by the Lewiston dredge of Placer Development (Ltd.) is on the Trinity River in Trinity County, Calif., about 9 miles north of the town of Lewiston (see fig. 1). The nearest rail point is at Rending, Calif., which is exactly 50 miles bar road from the dredge camp. Recently a very good section of State highway has been constructed from Redding to Weaverville, and it is now possible to use this highway for 35 miles of the distance between the dredging property and Redding. The remaining 15 miles, however, are over ordinary dirt road. No trouble is experienced in reaching the property except for a few weeks during the middle of the winter when snowstorms may make travel difficult but not impossible. At present the property consists of about 500 acres of patented land, which extends for about 3 miles along the main Trinity River and Stuart's Pork. It is being worked with one 7-cubic foot, Bucyrus-type dredge, which has an average monthly capacity of about 100,000 cubic yards. To the end of 1931 approximately 10,000,000 cubic yards of gravel had been dredged.

Jan 1, 1932

By R. F. Linfield

Figure 1-1 shows the basic transmitter design concepts used for the pulse system, the half-wave CW system, and the full-wave CW system. The antenna current waveform is also shown for each transmitter for typical operating frequencies and antennas. The switches shown in Figure 1-i were actually implemented using solid state devices. In all three systems the signaling format may be interrupted to conserve power and thereby extend battery life. Frequency accuracy and stability is achieved using a tuning fork oscillator in the transmitters and tuning fork filters in the receivers for all three systems. This provides the narrow reception bandwidths needed to enhance signal detectability. All three systems also use frequency assignment for identification purposes. The location schemes employed are likewise identical, each being based on detecting the null (signal minimum) of the horizontal magnetic field on the surface. Since these systems are basically similar, the primary purpose is to select the system which gives the maximum signal detectability on the surface from a manpack transmitter operating in the mine. Both the pulse and half-wave C W systems use a d. c. pulse to energize the loop antenna. However, with the pulse system, this pulse duration is short compared to the pulse repetition rate (prf), whereas with the half-wave C W system the pulse duration equals one-half the period of the switching frequency. In the pulse system, energy from the battery is stored in a capacitor so that during the switching interval the internal resistance of the power source can be considered almost negligible. Both transmitters must drive a loop antenna which is a reactive load having inductance, L, and resistance, Ra.

Jan 1, 1973

By Peter Grandstone, D. A. Jessup, D. B. Taliaferro

"INTRODUCTION Water flooding of oil sands in Texas as a means of secondary recovery of oil has been practiced mainly in the north-central part of the State, which includes the old shallow fields in eight counties, extending south through Wichita and Clay Counties on the Red River into Brown County.The Texas Railroad Commission, is empowered ""to promote conservation and prevent waste in the drilling, completion, operation, and abandonment of oil wells"" and ""to issue regulations necessary for fulfillment of these ends,"" granted The Texas Co. the first permit to inject water into the oil-bearing sand on December 7, 1935. The permit was granted after the Commission had conducted a number of hearings, which were attended by many operators interested in that method of secondary recovery. Through December 31, 1944, the Commission had granted 50 permits for water flooding. Of that number, 45 permits were issued for projects in north Texas, the remaining 14 being distributed throughout west and south Texas. By the end of 1944, there were 33 active and 5 abandoned water-flooding projects in the North Texas area, as is in figure I.Oil production in the North Texas area started in 1904 from the shallow sands (ranging from 100 feet to 800 feet in depth) of the Petrolia (or Henrietta) field in northern Clay County. Development was rapid and unrestricted during the boom period from about 1911 to 1918, and considerable waste of both produced oil and reservoir energy resulted."

Jul 1, 1946

By Ronald W. Schaefer

This report describes operations at the Rosiclare Fluorspar Works of the Aluminum Co. of America at Rosiclare, Hardin County, Ill. The works include the Fairview mine, the fluorspar mill, and related facilities. The publication covers exploration, development, mining and milling practices, mine-drainage problems, and other activities and is presented as part of the Bureau of Mines series of publications on mining and milling practices in various parts of the United States. The Rosiclare fluorspar area, for its size, has been the largest producer of high-grade fluorspar in the United States and probably in the world. The vein system in this area is over 5 miles long and 1/2 mile wide, and ore has been found as deep as 900 ft.

Jan 1, 1961

By G. R. Peterson

To determine the availability of lead and zinc from demonstrated resources, the Bureau of Mines evaluated 235 mines and deposits in 31 market economy countries. Of the 235 mines and deposits evaluated for this study, 186 were evaluated as zinc operations, 30 as lead operations, and 19 as copper operations. Demonstrated lead-zinc resources of market economy countries in 1981 were approximately 4.3 billion metric tons (t) of ore containing 221 million t of zinc and 97 million t of lead. Of these amounts, approximately 154 million t of zinc and 70 million t of lead are estimated to be recoverable. The analyses indicate that demonstrated resources in market economy countries should be sufficient to satisfy projected demand for primary lead and zinc through the balance of the century. The U.S. lead industry will continue to have a comparative advantage over the rest of the world industry, barring any drastic increase in the cost of compliance with pollution control regulations. It appears that the comparative disadvantage faced by the U.S. zinc industry will probably intensify owing to the relative quantity of lower cost zinc resources in other countries, especially Canada, Australia, Mexico, and Peru.

Jan 1, 1985

By W. M. Deaton

[The formation of gas hydrates in natural-gas pipe lines depends on temperature and pressure conditions in the lines as well as on the presence of condensed water. The operating pressure in a pipe line may be determined easily and usually is available from the records of operation, but the temperature seldom is known. In cooperation with the American Gas Association, the Bureau of Mines, in its investigation of gas hydrates, conducted a pipe-line-temperature survey and studied underground temperatures at depths at which pipe lines ordinarily are buried and the relationship of these temperatures to prevailing atmospheric conditions. A similar but more limited study of this type was, conducted by engineers of the Bureau of Mines a number of years ago.4/A summary of the earlier findings was included in a general report by the Bureau on the flow of natural gas through high-pressure transmission lines.5/ In the present study, data on temperature variations were obtained at several places widely separated geographically. This information should assist pipe-line engineers in designing and operating natural-gas pipe lines. In the pipe-line-temperature survey here resorted, a study was made along a 22-inch natural-gas pipe line: originating near Amarillo, Tex., and extending northwestward through New Mexico into Colorado (fig. 1). Some data also were collected along a 16-inch line extending southward from Amarillo. In the study of underground temperatures and their variation with atmospheric temperature, recording; equipment was installed at the]

Jan 1, 1941

By E. E. Maust

The present work is part of an ongoing Bureau of Mines effort to provide a better understanding of the fundamental phenomena involved in sulfide flotation, the role of oxygen in xanthate adsorption being one essential issue. Galena was chosen as the material around which to develop a conceptual model, partly because of its demonstrated oxygen sensitivity and partly because information on its properties and flotation behavior constitutes the largest part of the fundamental information available on sulfides of commercial importance. The model is formulated primarily in terms of surface electronic energy levels produced by oxygen and xanthate and is further developed using existing experimental evidence and its implications. Four major functions of oxygen are elucidated, and the relationship of these to the formation of lead xanthate, dixanthogen, and a surface compound is discussed. Though yet incomplete, the model provides a useful framework within which the results of diverse experiments can be related to one another in their proper perspective, as shown by a brief discussion and resolution of some apparently discordant results reported in the literature.

Jan 1, 1976

By J. B. Gayle

The merits of the various methods for dry-quenching coke have been the subject of numerous publications and almost equally numerous controversies for the past 40 years.5/ Most investigators have concluded that dry quenching is advantageous. Some have based their arguments on the improved physical properties of the resultant cokes. Others have claimed little or no improvement and have based their arguments on the economies acquired from the recovery and utilization of sensible heat. The extent to which the method of quenching influences the properties of the resultant cokes is of importance in connection with the operation of both commercial and experimental ovens. On the other hand, the recovery and utilization of sensible heat are economic problems related solely to commercial oven operation and- depend on the method of dry quenching used and the demand for a low intensity energy source. The scope of the present Bureau of Mines investigation has been limited to a comparative study of the properties of wet- and dry-quenched cokes produced from six coals and blends carbonized at flue temperatures of 2, 000° and 2,400° F. in the Tuscaloosa oven.

Jan 1, 1959

By John A. Breslin

The Bureau of Mines measured respirable dust in coal mines by means of multiple dust samplers worn by persons moving about the mines. The measurements were made primarily to evaluate the effectiveness of certain dust-control techniques; however, for this report, the data have been analyzed to determine the precision of the personal dust-sampling measurements. A total of 68 sets of measurements were available from multiple personal samplers. The measured dust masses were less than 1.0 mg because the sampling times were short. The coefficient of variation calculated from these data was 18.5 pct, compared with coefficients of variation ranging from about 10 to 30 pct, which were calculated from the most precise and extensive data available for fixed-point dust measurements made in coal mines. From this comparison, it is concluded that dust samplers worn by personnel are as precise as fixed-point samplers in measuring respirabe coal dust; the wearing of the samplers by someone moving about a mine does not contribute significantly to the variation in measurements made with these instruments.

Jan 1, 1983

By Ronald F. Balazik

[This Bureau of Mines study is intended to identify and evaluate potential effects of impending large-scale U. S. rail line closings (abandonment) on domestic nonfuel mineral industries. This is the first nationwide study of rail abandonment impacts focused on nonfuel minerals. The analyses presented is based principally on a survey of 200 rail freight records and on statistical tests that correlated 2,000 points in the Bureau's Mines Industry Location System (MILS) with 700 prospective abandonments throughout the United States. The conclusions derived from the analysis can be useful in evaluating proposed national rail abandonment policy rind legislation regarding nonfuel miner it shipping. Among these conclusions are the following: (1) Certain mineral materials (especially fertilizers) are likely to account for a large percentage of the rail traffic affected by abandonment in the next few years, but the total tonnage- involved will be small; (2) abandonment will adversely affect some mineral shippers, particularly local smart haulers; and (3 abandonment could significance reduce the opportunity to develop new resources or reopen defunct mining facilities. Despite these problems, however, the data examined in this study do not indicate that current abandonment trends will cause widespread disruption 01 domestic nonfuel mineral shipping.]

Jan 1, 1980