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By Richard H. Spencer, Warren G. Bender

Since the passage of the Coal Mine Health and Safety Act of 1969, the Bureau of Mines has made many advances in mine communications. These efforts have resulted in the following developments and demonstrations: • Surface-to-surface electromagnetic transmission of baseband voice signals through overburdens as deep as 600 feet. This transmission was achieved with equipment from the Interim Mine Rescue and Survival System Program, and demonstrated that baseband voice communications could be obtained through these overburdens in the absence of mine-generated noise; that is, when the mine power system was shut off. However, during mine operational conditions, the mine-generated noise proved to be so large that effective baseband voice communications to the desired depths could not be effected. • The development of beacon transmitters for locating trapped miners. This work was again the outgrowth of the Interim Mine Rescue and Survival System. Extensions of this work have led to reliable detection and location of trapped miners to depths of 1000 feet. The system, which makes use of a loop antenna deployed where the trapped miner is located, uses low-duty-cycle, tone-burst transmission. Portable tuned receivers and loop antennas are used on the surface to determine the location of the trapped miner. An extension of this work has led to a call-alert paging system concept, wherein a transmitter, similar to that used in the trapped miner system, is used to audibly and/or visually alert key mine personnel carrying pocket receivers that they are wanted at the nearest mine telephone. In addition, a roof-bolt paging system has been developed, wherein commercial paging and mine carrier phone equipment are used in conjunction with a long-wire "roof bolt" antenna to page individuals and relay to them short voice messages.

Jan 7, 1975

By Ivette E. Torres

For a study such as this, which summarizes and amalgamates much information collected, compiled, and utilized by the numerous U.S. Bureau of Mines country specialists and branch chiefs for inclusion in their country and regional reports that comprise the five other sections of 1992 Minerals Yearbook-International Review, it is clearly impossible to cite all sources of information used in its presentation, but some recognition is due. Generally speaking, this study and its related detailed studies on countries and areas would be much more difficult, if not impossible to complete, without the efforts of the personnel of our counterpart national mining and geological agencies throughout the world. Information that they collect, compile, and then publish, either in their own volumes or those of central statistical agencies in their countries, are the foundations on which this work rests. Thus, our appreciation is expressed to the multitude of persons employed by these agencies for their contributions.

Jan 1, 1994

By C. Stephan, E. Weiss, J. Trackemas, M. Sapko

The National Institute for Occupational Safety and Health (NIOSH), Pittsburgh Research Laboratory (PRL), in collaboration with the Mine Safety and Health Administration (MSHA), the mining industry, and seal manufacturers recently conducted a series of full-scale experiments within the underground experimental mine at PRL’s Lake Lynn Laboratory. The purpose of the experiments was toe valuate the explosion-resistant characteristics of several new seal designs for rapid deployment during mine emergencies. These seals can be deployed in 6 to 10 hr and are capable of with standing explosion overpressures in excess of 140 kPa (20 psi). These novel seal designs use available mine materials, do not require conventional rib hitching, and, most importantly, can substantially reduce exposure time for coal miners during sealing and mine recovery operations.

By Lisa Steiner, Robin Burgess-Limerick

In 2004, there were 646 underground coal mines in the USA employing 37,445 miners. These mines reported 3556 injuries to MSHA that year - 17% were associated with bolting machines (593 injuries), 8% with continuous miners (283 injuries), and 4% each with Scoop/LHD (1 51 injuries), shuttle cars (134 injuries), and personnel transport (145 injuries). The use of the frequency of reported injuries for the prioritization of risk control strategies has limitations because of the tendency to underestimate the importance of relatively rare but high-consequence events. Injury reports also underestimate the contribution of risk factors such as whole body vibration, which have a long-term cumulative contribution to an elevated risk of injury. However, taking these limitations into consideration, the results of the injury narrative analysis suggest the following hazards as the highest priority for elimination or control: • rock falling from supported roof • inadvertent or incorrect operation of bolting controls • handling continuous miner cable • collisions while driving LHD/Scoop, shuttle cars and personnel transport • rough road while driving or traveling in LHD/Scoop, SC & PT

By P. T. Brooks

Electrochemical machining sludge, a troublesome fluid waste product, was dewatered on a bench-scale basis by three alternative methods tested by the Federal Bureau of Mines. These methods would enable recycling 89 percent or more of the liquid content of the sludge and allow the dewatered solids to be dumped as landfill or processed further to recover contained nickel. Dewatering by vacuum precoat filtration was estimated to be the least expensive. Based on treating 20,000 gallons per day of sludge, precoat filtration costs were estimated as totaling 1.96 cents per gallon of sludge. Two options of an alternative method, comprised of acidification, reprecipitation, thickening, and filtration, were estimated to cost either 3.41 or 3.60 cents per gallon of sludge.

Jan 1, 1976

By R. V. Ramani, V. T. Burgos, J. A. McClay

The data for Test I describes an underground bituminous coal mine operation in a 48 inch seam, with an estimated production rate of 1,056,000 tons per year. The system includes four continuous mining sections, conveyor belt haulage, and a rail network for supply and personnel transportation. This section illustrates the input data sequence and the various report formats which may be selected for the printing of results. As explained earlier, at the present time, the elements of the Cost Data Library must be read in with the regular data input. Thus, in the input data listing, immediately following the required user input, are cards which contain the inputs of the cost library. Examination of the cost reports indicate the absence of cost values for some categories for which the system would normally be expected to incur costs. This situation has arisen due to the format of the cost data provided in the U. S. Bureau of Mines reports. An example of this is the charge of $20/ton for brattice cloth while no charge is indicated for stoppings. The test report data provided a single figure for ventilation cost without a supplemental breakdown. Thus the cost indicated for brattice cloth is actually the total ventilation cost. These explanations hold true for the data input and output for Test II, Appendix III.

Jan 1, 1975

By R. Ward Stahl

Fire has been one of man's most useful tools through the ages and certainly is a "must" for industrial progress but when uncontrolled is one of the most destructive agencies. This fact is even more important in a coal mine, where many persons and much expensive equipment are confined in a relatively small area. Means of escape from a burning area, as well as from the products of combustion, are often limited; and in many instances the entire surroundings are combustible. Numerous mine fires, which resulted in a high death toll and great financial loss through the years, have caused mine owners to search for the best fire-fighting equipment; much of this has been installed, the quantity depending largely upon the experience of the individual companies or neighboring mines in certain coalfields. A mine owner or operator has meager published information on the actual fire protection afforded and systems of fire-fighting inaugurated in the coalfields, by which he could compare his efforts and get some idea of the adequacy of his own protection. To further general knowledge of the subject, it was decided to survey a representative number of mines in the field and show what has been accomplished. Representative mines were selected in various coal beds; some had similar tonnage, so comparison could be made if desired.

Jan 1, 1957

By F. W. Cox

Exhaust emissions were measured from 25 aircraft turbine engines using Jet A fuel. Analytical apparatus, procedures, and results are described. Carbon monoxide, carbon dioxide, nitric oxide, nitrogen dioxide, and aldehydes were measured at engine operating modes representing power levels used in airline operation. Carbon monoxide, hydrocarbon, and aldehyde emissions were highest at idle and lowest at takeoff; oxides of nitrogen were lowest at idle and highest at takeoff. Of the total oxides of nitrogen emitted, nitrogen dioxide constituted from 10 to 100 pct, depending on the exhaust gas temperature. Engines retrofitted with smoke-reducing burner cans produced less carbon monoxide, hydrocarbon, and aldehyde emissions, and slightly more oxides of nitrogen then engines with standard burner cans.

Jan 1, 1972

By J. B. Zadra, S. M. Shelton, M. M. Fine

"Ferrograde manganese ore or its equivalent is essential to the manufacture of every ton of steel produced; although it is well known that there are large deposits of low-grade ore in the United States, the production of substantial amounts of ferrograde material from domestic sources presents a problem that becomes more and more critical as the stockpiled ore is depleted through inability to procure adequate supplies from foreign sources. Consequently, a program of laboratory and pilot-plant investigation designed to solve the problem of obtaining a domestic supply of manganese has been undertaken by the Metallurgical Division, Bureau of Mines.This paper is one of a new series that will include reports of results obtained in the various investigations conducted under the manganese program. The scope of the program and the organization that woo set up to direct and supervise the work were discussed in the foreword of the first paper of this series, Report of Investigations 3606, Manganese Investigations. 1. Concentration of Manganese Ores from the Drum Mountain District, Utah, by S. R. Zimmerley, J. D. Vincent, and C. R. Schack. Other reports will be published as the work progresses."

Mar 1, 1942

By C. E. Jordan

Domestic cobalt resources are relatively large, but low grade. The full potential for cobalt production from domestic sources is at least 19.4 million lb of cobalt per year exclusive of offshore resources. A summary of the cobalt processing technologies for the major domestic resources is presented in this Bureau of Mines report. The processing technologies for the Blackbird, Madison Nine, Duluth Gabbro, iron ore pyrite, laterites, and manganese sea nodules are nearly complete, but the economics are not favorable. Research on these resources should be limited to approaches that promise to cut the total processing costs by at least 50 pct. The most promising sources of cobalt are the spent copper leach solutions and siegenite from the Missouri lead ores. Research on cobalt processing from these two sources needs to be completed.

Jan 1, 1988

By Joseph S. Coffman

The Bureau of Mines investigated the availability of barite (BaSO4) from 35 U.S. and 41 non-U.S. mines and deposits in 17 market economy countries (MEC's). This evaluation assesses the availability of mud-grade barite, and concentrates consumed by the chemicals and fillers industries. The demonstrated resources defined in this analysis totaled 130 million metric tons (Mmt) of barite (contained BaSO4), yielding a potential 115 Mmt of recoverable barite concentrates. At the 1984 MEC production rate, the evaluated resources would last about 30 yr; however, this would include production costs of up to $100/mt concentrate. An average price needed to cover all costs of production over the life of each operation was determined for both mud-grade and chemical- and filler-grade barite products. Including a 0-pct discounted-cash-flow rate of return (DCFROR), regional weighted- average total production cost ranged from $38/mt for barite concentrates in Asia to $71/mt for U.S. operations. Transportation costs have the greatest impact, contributing up to 60 pct of the total cost of production. Rail transportation costs from the mines to U.S. markets are generally significantly higher than ocean shipping rates on imports.

Jan 1, 1986

By S. J. Davenport

[The tremendous increase in mine mechanization since 1929 has increased markedly the application of electric power in and about the coal mines of the United States. Cutting, drilling, and leading machines have replaced hand-mining methods in nary mines. As a result, expansion of the gathering haulage has necessitated introduction of extensive feeder, trolley, grid other power wires. (1)3/ In spite of this vast mechanization the fatality rate from electric shock has been on the decline. However, there are still too many accidents, and efforts to eliminate electrical hazards cannot be relaxed. It is hoped that an acquaintance with the physiological aspects of electrical accidents will make workers end management aware of the lurking dangers of this very common and extremely dangerous form of energy.]

Jan 1, 1951

By G. B. Shea

The accident experience of the California petroleum industry for 1927 was characterized by a decrease it .the number of fatalities. The year closed with a total of 41 fatal accidents, as compared with a total of 54 for the preceding year. 3 In percentage, the figure for 1927 represents a decrease of 24 per cent from that of 1926 and evidences the promising results of organized safety work, in which the industry in California has taken an absorbing interest. The percentage of decrease for 1927 is the largest recorded in any one year since the compilation of the fatality record in the California petroleum industry was begun. Although good progress has been made during the past few years, much remains to be done to reduce still further the human and economic waste caused by accidents. This review is intended to show the employee, as well as the employer, the proximate and contributing cause of accidents. To increase the value of the report, preventive measures in various instances are suggested, on the theory that accidents of a similar nature will occur unless remedial action in taken to remove the cause.

Jan 1, 1928

By H. B. Cooke

In connection with its researches on the crude petroleums of the United States, the Bureau of Mines has made a particular study of apparatus for the distillation of hydrocarbon mixtures. While this study is still incomplete it has already resulted in the development of considerable laboratory and semi-plant equipment, motet of which has been described in various publications of the Bureau. The laboratory apparatus (Hempel distillation) and method gives satisfactory comparative results in the laboratory examination of crudes and have been found applicable to crudes of all types, but the agreement of laboratory and plant distillations is not as close as might be desired. This is due, in part, to limitations in size and construction of the laboratory apparatus. Some refiners claim that the Bureau of Mines' laboratory method (Hempel distillation3) for distilling crude petroleum, does not show the full gasoline content of the oil, while others have stated that it indicates more gasoline than can be obtained from the crude commercially. This difference of opinion among refiners results largely from the great variation in stills used and methods of operating them. The Bureau's experience has shown that crude oils from different fields vary widely in character; in fact, that it is not yet possible to classify crude's adequately on the basis of their Down chemical and physical characteristics. As a result of the differences that exist among crudes, and of the difficulty of designing refinery equipment, no standard practice has yet been adopted for the commercial distillation of petroleum, and ma" types of stills are used in the refineries of this country. Although many factors enter into the design of equipment and the development of commercial practice in refining of crude oil, there

Jan 1, 1924

By Joseph N. Harstead

This Bureau of Mines report provides information on the first 49 water-flood projects (or units) in Nebraska. All injection was in the ?D? or "J" Cretaceous sands of western Nebraska. Specific data presented include location, map, discovery and development, water supply and injection, oil and water production, estimates of oil in place, primary and secondary recoveries. The 49 projects studied) including four dual-zone projects, should recover about 126.5 million barrels of oil. Eighty-six percent of the estimated oil had been recovered by the end of 1966. Abundant water was found near most projects.

Jan 1, 1967

By G. R. Hopkins

"Summary An apparent decline in fuel efficiency at refineries, which first became came evident in 1930 and continued through 1933, was checked in 1933 when the average amount of heat needed to refine a barrel of crude oil amounted to 660,000 B.t.u. This compares with an average requirement of 692,000 B.t.u. In 1932 and with a low of 639,000 B.t.u. in 1929. (See fig. 1.) The improvement in fuel economy in 1933 probably was closely related to the increase of 5 per cent in crude runs to stills. As much of the fuel burned at refineries is utilized for purposes other than under crude-oil stills and in relatively stable amounts, it is evident that a material increase in crude runs will usually reflected in a decrease in average fuel requirements. Another factor which has influences fuel economy at refineries in the past is the trend in cracking, a refining process requiring more than the average expenditure of heat. In 1933 production of gasoline by cracking increased slightly, but no appreciable rise in heat requirements resulted as an equivalent amount of fuel was saved in improved technique, particularly in the field of heat exchange.Since the beginning of the refining industry, the transition in fuels has been from solid to liquid to gaseous; in other words, the leadership was first held by coal, then passed to oil, and is now held by gas. In 1933, 54.7 percent of the total heat units generated came from gas, 39.0 percent from oil (including acid sludge), and 6.3 percent from coal and coke. The principal change in the relative importance of the various refinery fuels in recent years has been the rapid growth in consumption of refinery or still gas at the expense of all the other common fuels. Still gas owes its ascendency to its cheapness and availability, and probably it would have become the primary refinery fuel years ago if recovery methods had been perfected. The relative importance of coal showed a small increase in 1933, the first gain recorded since these surveys were inaugurated in 1925. The increase in use of coal was undoubtedly due to increased operations at plants using it,"

Feb 1, 1935

By Charles L. Kimbell

While the statistical summary focuses on 1991 data, this update and outlook section draws on information available to the author as of the date of final preparation in early 1993. For all the press notoriety associated with the shift in the Near East crisis from the defensive posture of Desert Shield to the restoration of Kuwaiti sovereignty through Desert Storm, this was not the dominant event governing global economic thinking in 1991 and the first half and more of 1992. From the global perspective, the momentous political changes in the area that was the U.S.S.R. and in the smaller emerging transitional economy states of Eastern Europe will have even greater current and long-lasting effects on world mineral industry activities than the crisis in the Near East.

Jan 1, 1993

By Charles Prasky

This report describes bench-scale studies and pilot-plant development of the Bureau of Mines process for roasting iron ores with a ferrous scrap reductant, such as discarded automobile hulks, to yield artificial magnetite. Quality magnetic concentrates containing about 66 percent iron and 6 percent silica with iron recoveries of over 90 percent were obtained after roasting fine-grained oxidized or nonmagnetic taconite with unburned, sheared automobile hulks in a rotary kiln. The relatively complete oxidation of the lighter gage metal in the automobile during roasting resulted in a metallic byproduct consisting of the unconsumed heavier gage metal scrap. This residual or tailored scrap is potentially useful as heavy melting stock and has more value than the original automobile hulk.

Jan 1, 1970

By Andrew B. Cecala

The Bureau of Mines conducted laboratory and in-mine tests on the Racal airstream helmet (Model #AR21) to evaluate its protection efficiency. Laboratory tests indicated that as ambient air velocity increased, the protection offered by the helmet decreased. In tests conducted at several coal mine long-wall sections with face velocities under 400 fpm, the helmet was 84 pct effective at reducing respirable dust in the miner's breathing zone. However, at a high-velocity section, 1,200 fpm, the efficiency of the helmet was significantly reduced, confirming our laboratory results.

Jan 1, 1981

By Christopher C. Jobes, Alan G. Mayton, Farid Amirouche

Based on prior mine vehicle studies of operators’ exposure to whole-body vibration, researchers from the National Institute for Occupational Safety and Health (NIOSH) evaluated four seat designs on mine haulage vehicles, with regard to roadway-induced jarring/jolting and operator comfort. Investigators collected objective and subjective data from vehicle operators on two existing and two NIOSH seat designs. This study included time and frequency response data using accelerometers and a data recorder, operator perceptions of jarring/jolting and discomfort levels using a linear visual analogue scale, and data from a questionnaire developed for this study. Results from the analysis of subjective data show that operators generally favoured the NIOSH-designed seats over the existing seats. The results of analyses from the absorbed power method and the threshold limit method, based on ISO 2631-1 (ISO, 1985), support the premise that NIOSH seat designs are superior to the existing vehicle seat designs on both models of mine shuttle cars used in the study. The NIOSH seat designs, featuring viscoelastic foam padding, were more effective in reducing vibration energy for operators exposed to vehicle jarring/jolting. In this paper, the performances of the NIOSH and existing seat designs are compared relative to the operator’s exposure to vehicle vibration (mainly jarring/jolting).