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By Lloyd Williams

1. This investigation shows that the Sewanee bed is the only coal bed being mined in Sequatchie County. Other coal beds are present, but as they do not contain known recoverable reserves, estimates of reserves were made only for the Sewanee bed. 2. Known measured and indicated reserves in the Sewanee bed, based on a minimum thickness of 14 inches and on 1,800 short tons per acre-foot of coal in place, are estimated to be 76 million short tons as of January 1, 1953. Of this total 62 million short tons represent coal 28 inches and more thick. Areas in the bed were omitted from the estimate because available data relative to the bed characteristics were insufficient to permit making an estimate conforming with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves determined by this investigation.

Jan 1, 1955

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 high funding level program plan.

Jan 1, 1980

By C. E. Brechtel

This project describes the design and testing of large face ventilation systems for oil shale mining. A design data base was generated by reviewing general industry practice, oil shale industry planning, and technical literature. Conceptual designs for seven different systems were developed and evaluated for suitability. A large, free-standing, jet fan and reversible fan with rigid duct were selected for fabrication and testing. The two systems were field tested in a dead-end heading 55 ft wide by 30 ft high and 320 ft long. System performance was optimized using measurements of air flow direction and air velocity. Total system performance was then measured using SF6 tracer gas released to simulate blast fumes, hot diesel exhaust, methane layering and methane from a blasted muckpile. Field testing indicated that both systems delivered similar performance. The jet fan offered some clear advantages because of its mobility, ease of oper-ation and lower power requirement. It also offered some functional advantages in ventilating for methane because of it high average velocity.

Jan 1, 1985

By Richard D. Miller

This Bureau of Mines publication contains analyses and related source data for 224 natural as samples from 18 States. Of the total, 191 sam¬ples were collected during calendar year 1981. The remaining 33 samples were collected during previous years, but releases, granting permission to publish were not received until 1981. All samples were obtained and analyzed as part of Bureau of Mines investigations of the occurrences of helium in natural gases of countries with free market economies. This survey has been conducted since 1917. The analyses published herein were made by the mass spectrometer and special helium apparatus described previously (1-2).3 The results of the investigation of the occurrences of helium are published annually to make the information available as soon as possible to the gas industry and the general public. Twenty-five publications have presented the results of 12,827 gas analyses made prior to 1981. The first three bulletins (1-3) contain analyses and related data on 5,218 gas samples collected from 1917 through 1960; these bulletins have been supplemented annually by information circulars (4-17, 19-24) containing 7,609 analyses of samples collected since 1960.

Jan 1, 1982

By Emory Smith

The Victorville cement plant of the Southwestern Portland Cement Co. is located about 1 mile from the city of Victorville, Calif. Two transcontinental railway systems, the Atchison, Topeka & Santa Fe, and the Southern Pacific Railroad, afford shipped facilities. The plant is modern and well kept, as the officials, especially the higher operating officials, take pride in the appearance of the place. Dust has been practically eliminated by the installation of dust collectors and wet grinding. The plant has a rated capacity of 5,000 barrels of cement daily.

Jan 1, 1929

By F. R. Cattoir

This Bureau of Mines study investigated molten salt electrorefining for beneficiating low-grade, high-carbon ferrochromium products which can be readily produced from domestic chromite concentrates. A second objective was to refine commercial ferrochromium into low-iron chromium products. Electrorefining of both types of ferrochromium in molten CaC12-NaCl-CrC12, CaCl2-MgC12-CrCl2, or KC1-LiCl-CrCl2 electrolytes produced chromium-iron products with virtual elimination of other impurity elements and some lowering of the iron content, Over 90 percent of the chromium present in the feed materials was recovered. The electrodeposited products were upgraded further by magnetic separation techniques into chromium containing less than 5 percent iron. The technical feasibility of preparing a premium chromium product from a low-grade, high-carbon ferrochromium made from domestic chromite was demonstrated. Chromium virtually free of carbon, oxygen, and silicon from high-carbon ferrochromiums was produced. In addition, the amenability of three commercial grades of ferrochromium to electrorefining and magnetic separation for preparing chromium metal containing less than 5 percent iron was determined.

Jan 1, 1969

By Edmund S. Leaver, A. P. Towne, Jesse A. Woolf

Part of the work of the Precious Metals Section is to conduct oretesting experiments on ores selected as representative of various mining districts or areas . The projects are authorized by the Metallurgical Division , and only those ores in which gold and silver or gold or silver constitute an essential part of the total values are assigned to the Precious Metals Section . Such ores include those containing the precious metals only as commercially important ingredients , as well as those containing base metals such as copper , lead , and zinc along with the gold and silver . In many instances the "ore " may be a tailing product of a grade good enough to warrant retreatment , or a concentrate for which it is desirable to develop a method of treatment to avoid the expense of shipment to a smelter . It is evident that in general the greater part of this ore - testing work is done according to standard testing procedure , such as cyanidation, amalgamation, gravity - concentration , and flotation , or a combination of these methods . The standard methods of conducting such tests have been outlined in previous reports of ore - testing studies . However , since the inauguration of this oretesting program 6 years ago , the ores submitted under authorization have become increasingly more refractory to simple methods of treatment. Consequently, a considerable number of the projects completed during the fiscal year 1941 have required an unusual amount of work and in some instances have developed into real research problems . For such ores more complete microscopic and spectroscopic examinations and more complete chemical analyses

Feb 1, 1942

By G. E. McElroy

The Coeur d'Alene minim, district of Shoshone County, Idaho, has been one of the largest and most active lead-silver producing districts in the United States for the last 40 years. The mines of the district enjoy exceptional natural advantages with respect to ventilation in that the veins apex high on mountain sides and are most often developed to considerable depths, up to 2,000 feet, by adit and crosscut tunnels under conditions that develop large natural draft pressures; the increase of temperature of the rock with increase of depth from surface in at a low rate; and the average surface temperatures are low. These natural conditions have, in the main, resulted in well-ventilated mines with low temperature conditions throughout. However, where the development has been carried to considerable depths below the lowest level of surface entry, natural-draft ventilation has proved inadequate, and mechanical ventilation systems have been installed on the three largest mines of the district. Local conditions, more particularly those in dead-ended working places, have also required auxiliary ventilation by will fan-pipe units in these and other mines. A particular feature of the district is the number of exceptionally long crosscut tunnels that have been driven to provide entry to vein systems from low points adjacent to milling and transporta¬tion facilities. Three of these tunnels are approximately 2 miles long, and lengths of 3,000 to 8,000 feet are quite common.

Jan 1, 1931

By James Westfield

A brief résumé follows of some of the most recent activities of the Division of Coal-Mine Inspection that have had a favorable effect. on health, safety, and injuries at coal mines: 1. There were approximately 8,510 active coal mines in the United States during 1955. In all, 82,389 regular Federal inspections of coal mines have been made since Public Law 49 became effective in May 1941; 9,823 of these inspections were made during 1955. 2. The Bureau of Mines introduced the revised Coal-Mine Accident-Prevention Course for Supervisors in the coal-mining industry on March 1, 1948. Since that date, 19,455 supervisors and those aspiring to official positions have completed such training conducted by personnel of the Division of Coal-Mine Inspection.

Jan 1, 1956

By A. J. Kraemer

The properties of crude petroleum continue to interest the Bureau of Mines and constitute an important phase of its major studies on the mineral resources of the United States. The Bureau's interest in the subject has been intensified by frequent requests for information on the characteristics of crude petroleum from various producing fields. Since its inception the Bureau of Mines has collected and analyzed samples of typical oils and at present has surveyed and classified crude petroleums from nearly all the known oil fields of the Western Hemisphere. Results of these surveys have been presented in various Bureau of Mines publications. (See bibliography, appendix A, p. 145.) The nature and comparative value of crude oils from various countries and the extent to which these oils may be considered potential competitors for markets are of manifest importance to the petroleum industry in all lands, largely because all crude oils, wherever produced, are either actual or potential competitors for a market with all other crude oils. The numerous discussions of foreign production of oil that have appeared in the technical press in the past indicate the great interest of the United States in this subject.

Jan 1, 1937

By D. Bienstock

In connection with air-pollution studies, the Bureau of Mines is cooperating with the U.S. Public Health Service in investigating the use of solids for removing sulfur dioxide in concentrations of less than 0.5 percent from combustion and waste gases. Removal of sulfur dioxide at flue-gas tempera¬tures would no longer result in the cooling of scrubbed gas, which is inherent to liquid scrubbing processes used exclusively in industry today. Results are reported of extensive investigation, using metallic oxides as absorbents, adsorbents, and oxidation catalysts at 130° and 330° C. (temperatures at which flue gas may be treated in powerplant practice). The most active absorbents tested were the oxides of manganese, cobalt, copper, and alkalized alumina; 23 to 33 grams of sulfur dioxidn were removed by 100 grams of absorbent at 130° C., while scrubbing more than 90 percent of the sulfur dioxide from a simulated flue gas, and 19 to 61 grams of sulfur dioxide were removed at 330° C. A more detailed study is reported on absorption and regeneration, using manganese oxides and alkalized alumina. Adsorption of sulfur dioxide on activated carbons and molecular sieves at elevated temperatures is considerably less efficient than removal by absorption--a maximum of 7 to 8 grams of sulfur dioxide could be removed with 100 grams of adsorbent at 130° C. A potash-promoted vanadium pentoxide is effective in converting sulfur dioxide to trioxide; complete conversion in a simulated flue gas containing 0.35 percent sulfur dioxide was obtained at 365° C. Pilot-plant and cost studies are being made by the Bureau to determine the economic feasibility of removing on an industrial scale the sulfur dioxide present in gases in low concentrations.

Jan 1, 1961

By R. L. Rankin

The program objective was to conduct surveys of respirable dust concentrations in coal mining operations at locations outby the working face. The results of these surveys were directed toward 1. identifying outby dust sources, 2. evaluating the severity of the major dust sources, 3. establishing dust sampling frequency, 4. establishing dust sampler locations, and 5. assessing the? areas of influence of the dust sources. The study included dust sampling of only nonhigh risk personnel and areas at six dif-ferent mines. Thirteen continuous mining, four longwall and two conventional mining sections were sampled. The severity of outby respirable dust sources such as load points, runways, dump points, beltways, transfer points and main haulage operations were characterized and areas within the mine were ranked according to severity. Information on engineering controls was also acquired. Guidelines for implementing a dust sampling program are presented and include sampler locations, ventilation surveys, dust surveys, effects of shift-to-shift variations, and sampling frequency.

Jan 1, 1980

By David R. Flinn

This Bureau of Mines report describes methods to electrodeposit erosion-resistant titanium diboride coatings from molten alkali metal borate baths at 900° C. These coatings have been shown to be highly resistant to material loss during impingement with high-velocity alumina and silicon carbide powders, and they show promise as protective coatings to reduce metal loss in erosive chemical environments, such as coal gasification systems. The most erosion-resistant coatings were prepared on nickel, Inconel, and molybdenum from an electrolyte containing LiBO2, NaBO2, Na2Ti03, and TiO2. The best coatings were deposited at current densities of [~]20 ma/cm2, using titanium or titanium diboride anodes. Erosion-resistant coatings were shown to exhibit (1) a high degree of crystallographic orientation along the (100) or (110) planes, (2) a chromium impurity level of less than 3 pct, and (3) a uniform, smooth, consolidated surface appearance when viewed under a microscope or by scanning electron microscopy. Optical spectroscopic studies of the molten electrolyte suggest that the lower valent (+3) titanium ion predominates in the baths.

Jan 1, 1979

By R. R. Sayers

Under compuision of the present urgency to implement the President's promise to make the United States the arsenal for the democracies there is a tendency to demand a relaxation of restrictions on hours of labor and to speed up all industrial processes. The pressure is the more insistent with growing realization of the importance of the time factor in the success- ful prosecution of the war effort and the lack of skilled workers due to (2) operation of the draft, lack of an apprentice system in industry, and loss of skill by workers unemployed for long periods during the depression. With "total" war such as it is today the probabilities are that everyone will be required to exert greater effort (in many instances in activities to which they are unaccustomed) for longer periods than ever before has been necessary. The question arises, "What will be the aftereffects as well as the immediate effects on health, safety, and efficiency?" A review of the literature leaves the impression that this question has not been an- swered completely, especially as regards the ultimate effects. Mechanization, speeding up of industrial processes, mass produc- tion, and the small industrial concerns present many problems to indus- trial medicine. Does the tendency to expect the worker to produce at full speed all the time he is on the job decrease the effectiveness of the shorter working hours and cause undue fatigue, loss of efficiency, and increased accident proneness? The answer is important as this condition is likely to be intensified by the exigencies of the present emergency. According to Viteles (1)3, The increased tension under such conditions of work appears to offset the savings in muscular force made pos- sible by the machine. The tension, the speed, the subject- tion to specialization of work and a rhythm uncontrolled by the individual promote fatigue, characterized by a "decrease in the power to work, a decrease in pleasure taken in work, and a decrease in the enjoyment of the hours spent away from work."' The crowding of workers in temporary structures without proper provision for comfort and health may add greatly to the general fatigue factors already present in many industrial establishments. In 1932 Lockhart (2) stated that the production and maintenance of a healthy, satisfied industrial population is the most urgent necessity, involving problems so serious as to constitute a national task too great economically to be relegated to industrial concerns. If this was true in 1932, it must be doubly so today.

Jun 1, 1942

By R. J. Leary

This investigation was conducted to determine the effects of various rare-earth metal addition practices upon the macrostructure and the pattern of sulfur distribution in steel ingots. Heats of plain carbon steel were melted in a 1-ton, basic electric-arc furnace. Melts were treated with mixtures of rare-earth silicides, aluminum, and cryolite either in the furnace before tap or in the ladle after tap to determine the effects of this form of rare-earth treatment upon ingot macrostructure. Steels thus treated with rare earths in the furnace were characteristically free of the gross subsurface nonmetallics which typically result from conventional rare-earth treatments. Steel treated in the ladle showed only a few such nonmetallics, and practical techniques were developed for eliminating most of these. Results showed that furnace deoxidation was controlled by the concentration ratio of rare earths: aluminum. During casting, deoxidation was controlled by the concentration of rare earths. Oxygen contents equivalent to vacuum ladle degassing resulted from air-melt furnace treatments with the rare-earth mixtures described. Rare earths in steel inhibited the onset of equiaxed grain formation during ingot freezing, and also virtually prevented interdendritic segregation of sulfides.

Jan 1, 1968

By Vernon C. Davis

In initial attempts to mine taconite by conventional open-pit methods, the material tended to break into tabular blocks that were too large to be handled by conventional shovel dippers and were unsatisfactory in an ordinary crusher feed. A great amount of secondary blasting was necessary, which added considerably to the cost of mining. The Bureau of Mines and others are engaged in studies designed to contribute to the solution of taconite-mining problems. These studies concern problems related to drilling techniques and patterns, types and methods of use of explosives, and other factors relative to effecting maximum fragmentation at minimum cost. This report, is concerned with study of the application of shaped charges in drill holes, the effectiveness of shaped charges as compared to capped charges in secondary blasting, and the merits of different drilling patterns and methods of detonation of conventional-explosive charges. Fragmentation of taconite at or near the surface is controlled or strongly influenced by joint and bedding planes. Since all tests in this study were made in a jointed and bedded area, a definite conclusion as to the relative effect of a shaped charge in a drill hole, as compared to a conventional charge at greater depths and tighter ground, is precluded. However, application of shaped charges in primary blasting of taconite appears to be of no advantage. In secondary blasting of taconite, conventional, capped charges produced better breakage than shaped charges of the designs tested. Based on the results of conventional blasting practice in horizontal-, inclined-, and vertical-hole tests, no better fragmentation is obtained from blasting either horizontal or inclined holes, compared to vertical holes. Holes drilled in staggered parallel rows that intersect both series of joint planes at the greatest possible angle, give maximum breakage compared to rows paral-lel to one of the series of joint planes. Methods of detonation made little difference in breakage; but the milli-delay caps produced the best conditions for moving the broken rocks.

Jan 1, 1953

By Ralph H. Espach

In the spring of 1943, when it was evident that the Tensleep sandstone in the Elk Basin field, Wyoming and Montana, held a large reserve of petroleum, Bureau of Mines engineers obtained samples of oil from the bottom of nine wells and analyzed them for such physical characteristics as the volumes of gas in solution, saturation pressures or bubble points, shrinkage in volume caused by the release of gas from solution, expansion of the oil with decrease in pressure, and other related properties. The composition of the gas in solution in the oil was studied. The pressures and temperatures existing in the reservoir and the productivity characteristics of the oil wells were determined. The data obtained indicate that the oil in the Tensleep reservoir of the Elk Basin field has unusually varying physical characteristics, such as a saturation pressure of 1,250 pounds per square inch absolute and 490 cubic feet of gas in solution in a barrel of oil at the crest of the structure, and a saturation pressure of 530 pounds per square inch absolute and 134 cubic feet of gas in solution in a barrel of oil low on the flanks. The hydrogen sulfide content of the 6a r; in solution in the oil varies from 18 percent for oil on the crest to 5 percent for oil low on the flanks of the structure. Of even greater significance is the fact that these and other variable characteristics of the reservoir oil are related to the position of oil in the structure. Many geologists and petroleum engineers have considered all the oil in a petroleum reservoir to have uniform physical characteristics and that equilibrium conditions prevailed in all underground accumulations of oil and gas. That such is not always so is borne out by the results of the study made by the writers.

Jan 1, 1951

By S. J. Aresco

The Bureau of Mines has been active in promoting the purchase of coal for Government use under specifications that define the requirements in terms of heating value of the coal, expressed in British thermal units, and the composition as shown by proximate analyses. To these, when required, are added the ash-softening temperature, the free-swelling index, and the Hardgrove grindability index. Under most of these specification contracts the bidders guarantee the quality of the coal, and that guaranteed by the successful bidder becomes the standard of his contract. The deliveries are sampled in accordance with instructions4/ issued by the Bureau of Mines; the samples are analyzed in the Bureau laboratory to determine whether the coal is of the quality guaranteed by the contractor and, if it is not, a price adjustment is made. Analyses of the delivered coal and tipple samples (samples collected at mine tipples as coal is being loaded into railroad cars or trucks) provide valuable data for use in evaluating future bids. In addition, the continuous .sampling of coal as delivered is a check on the practical results obtained in burning the coal.

Jan 1, 1958

By R. H. Lien

The Bureau of Mines developed a flue gas desulfurization process as part of its goal of minimizing the undesirable environmental impacts associated with energy and mineral-processing plants. The modified citrate process involves absorption of sulfur dioxide (S02) in a buffered citric acid solution. The S02-loaded solution is regenerated by countercurrent contact with steam in a packed tower. The wet S02 product is then dried and can be liquefied or further processed to make sulfuric acid. Test data from process investigation unit studies are presented. Material balances, flowsheets, and cost estimates are given for recovering S02 from copper smelter reverberatory gas, lead smelter sintering machine tail gas, and power-plant stack gas. Operating cost estimates show the process will add $0.04 per pound of copper, $0.01 per pound of lead, and $0.015 per kwhr to the cost of the respective operations. These costs could be substantially reduced if a source of waste heat was avail-able to provide the process steam requirements.

Jan 1, 1982

By H. L. Retcofsky

Carbon-13 nuclear magnetic resonance (18CNMR) spectra of nine 2-substituted pyridines, seven 3 -substituted pyridines, and nine 4-substituted pyridines have been obtained and analyzed. Substituents included both electron-releasing groups and electron-with hawing groups. Substituent effects on the magnetic shieldings of the ring carbons, except for those in the 2-positions of 2-substituted pyridines, were found to be quite similar to the effects reported for the monosubstituted benzenes, Thus, at least to a first approximation, the two classes of compounds have similar shielding mechanisms. Shieldings of the carbon atoms in the 5-positions of 2-substituted pyridines and those in the 6-positions of 3-substituted pyridines were found to reflect electron release or withdrawal by substituent groups, The pyridinium cation and the compounds 2,2'-dipyridyl and benzonitrile were also investigated.

Jan 1, 1969