Search Documents

By L. C. IlsLey

As part of its work for the improvement of safety conditions in mines , the Bureau of Mines has undertaken to establish a list of permissible storage - battery locomotives for use in gaseous mines , and , to this end , has issued Schedule 15 , "Procedure for Establishing a List of Permissible Storage -Battery Locomotives for Use in Gaseous Mines . " Up to the present time , two approvals * have been issued under this Schedule , and considerable testing work done on four other applications which have been made for approval . Prior to the publication of Schedule 15 , the Bureau conducted both field and laboratory investigations to determine the hazard from the batteries used in mine locomotives . ** These investigations indicated that the safety of the locomotive would depend largely on proper care of the battery , also on the use of a battery as mechanically rugged as possible . For this reason the Bureau staff , in testing locomotives submitted for approval , considered it advisable to subject the batteries to a jarring or bumping test to prove their adequacy as regards mechanical endurance and ruggedness . These tests on the batteries of the locomotives are described below.

May 1, 1922

By J. C. Meeks, C. L. Klingman

An instrument that is sensitive , portable , safe , and low in cost was developed by the Bureau of Mines for detecting helium leaks by comparing the thermal conductivity and flow rate of the atmosphere around the suspected leak against a reference of helium- free air . A vacuum pump pulls the sample gas through a restriction and over thermistor elements , the combined electrical output of which is affected by thermal conductivity and flow rate of the sample gas . Tests showed that the battery - operated Helium Leak Detector was effective and rugged instrument that could be operated safely in explosive atmospheres . The instrument could also detect , but not identify , other gases such as methane , hydrogen , argon , carbon dioxide , and Freon 12 .

Jan 1, 1964

By John J. Henn

As part of the U.S. Department of the Interior programs on rutile, authorized by the Office of Emergency Preparedness in June 1967 under provisions of the Defense Production Act, the Bureau of Mines reviewed available literature on major proposed processes for producing rutile substitutes. The processes are grouped according to the major processing step, and important operating features are described. Sixty-one references are cited.

Jan 1, 1970

By Sidney Katell

This report covers the period January 1963 through December 1963; it is a continuation of the series that began with the publication of Information Circular 7516 in October 1949. Also, it is the fifth in a series of reports prepared under a cooperative agreement between the Bureau of Mines and the American Association of Cost Engineers. The agreement provides for the publication of an annual cost bibliography with the work load involved in the preparation shared equally. The abstracted articles, concerned with all facets of cost engineering in the field of chemical and petroleum plants and related subjects, are from the following sources: 1. American Association of Cost Engineers Bulletin. 2. Bureau of Mines Information Circulars. 3. Bureau of Mines Reports of Investigations. 4. Chemical Engineering. 5. Chemical Engineering Progress. 6. Chemical Week. 7. Coal Age. 8. Coal--Today and Tomorrow. 9. Coal Utilization. 3/ 10. Cost Engineering. 11. Hydrocarbon Processing and Petroleum Refiner. 12. Industrial and Engineering Chemistry. 13. Nucleonics. 14. Oil and Gas Journal. 15. Petroleum Management. 16. World Oil.

Jan 1, 1964

By F. D. Everett

The exploration work on a seleniferous tuff deposit near Lysite, Wyo., was confined chiefly to an area of approximately 1 square mile selected on the basis of prior examination and sampling work by the Bureau of Mines. This area was superficially explored by digging and sampling over 2,000 feet of trenches and 15 test pits. The surface sampling indicated that the deposit might contain a multimillion-ton reserve of easy-to-mine volcanic tuff assaying more than 0.01 percent Se. Later, 11 holes, ranging in depth from 57 to 135 feet and totaling 929.4 feet, were drilled under contract using a dry rotary drill. Samples for assay were cut at 5-foot intervals or at noticeable physical changes in the formation being drilled. Of the 206 samples assayed from the drilling, only 8 contained more than 0.005 percent selenium, and 2 of these assayed as high as 0.012 percent Se. Chemical analyses of samples obtained from six holes drilled by the Nugget Coal & Timber Co. to the south of the area explored by the Bureau of Mines showed that no selenium-bearing formations were encountered in that work. Two of 72 samples taken from 42 validation pits dug by claim holders contained more than 0.005 percent selenium. The exploratory work established that the selenium mineralization is erratically distributed in small irregular bodies and is not confined to any one tuff bed. Because of the lack of correlation between the infrequent showing of low-grade tuff, neither the extent nor grade of the reserves could be calculated.

Jan 1, 1957

By W. E. Brown, P. R. Porath, V. Miller, C. E. Wood, C. Prasky, E. P. Barrett

"INTRODUCTION This investigation was a part at the Bureau of Mines program for the production of critical and essential materials needed for the war.The Boykin Committee for investigating the steel shortage aided in obtaining an appropriation to be expended by the Bureau of Mines in studying the utilization of North Dakota lignite in the manufacture of hydrogen that could be used in the production of sponge iron from low grade ores of Minnesota.OBJECT OF INVESTIGATIONThe investigation was conducted by the Bureau of Mines to ""determine the workability of the proposed bubble-hearth process and its possible use in connection with an experimental plant for the gasification of lignite being operated by the Coal Division of the Bureau of Mines at Grand Forks, North Dakota.ACKNOWLEDGMENTSThis report is one of many on various aspects of the Bureau of Mines program directed toward the more effective utilization of our mineral resources.Investigations of our mineral resources are conducted by the Mining Branch, L. B. Moon, chief, and by the Metallurgical Branch, O. C. Ralston, chief.The scope of the report falls in the province of the Metallurgical Branch, whose activities embrace the separation of difficulty beneficiated ores, the production of pure metals from domestic deposits, the exploration of marginal ore reserves, the recovery of secondary metals, and the improvement of present industrial metallurgical practice."

Jun 1, 1947

These inspection standard have been prepared for use in the Federal inspection of strip mines producing, bituminous coal, anthracite, and lignite. This circular is a revision of the Safety Code for Strip Mining, which was prepared by the Bureau of Mines and employed as a guide for Federal inspectors. Numerous changes have been made in the original code to keep the in step with improvements in the industry. With continuing changes in mining methods and facilities some of these standards may become inapplicable and further revision may be advisable. Therefore, questions regarding these standards, and suggestions regarding new standards should be brought to the attention of the Bureau of Mines. Few States haves laws pertaining to strip mines, but where such laws do exist it is possible that some of the standards may conflict with them. In cases of conflict, the intent is not to advocate noncompliance with State laws, but to suggest reconsideration of such laws or safety orders.

Jan 1, 1946

By Gerald T. Homce, James C. Cawley

Problem: CFOI and SOII data show that 2,287 U.S. workers died and 32,807 workers sustained days away from work due to electrical shock or electrical burn injuries between 1992 and 1998. Method: The narrative, work activity, job title, source of injury, location, and industry for each fatal electrical accident were examined. A primary causal factor was identified for each fatality. Results: Electrical fatalities were categorized into five major groups. Overall, 44% of electrical fatalities occurred in the construction industry. Contact with overhead power lines caused 41 % of all electrical fatalities. Discussion: Electrical shock caused 99% of fatal and 62% of nonfatal electrical accidents. Comprising about 7% of the U.S. workforce, construction workers sustain 44% of electrical fatalities. Power line contact by mobile equipment occurs in many industries and should be the subject of focused research. Other problem areas are identified and opportunities for research are proposed. Impact on Industry: Improvements in electrical safety in one industry often have application in other industries.

By Thomas M. Barczak

This U.S. Bureau of Mines study evaluates factors that influence longwall support and strata interaction. The longwall system is composed of an immediate and main roof structure and three supporting foundations: longwall panel, powered roof supports, and gob waste. The main roof forms a structure that is generally supported by all three foundations, while the immediate roof acts as a beam that cantilevers from the coal face to the powered support. In most cases, shield loading involves a complex interaction of both main roof and immediate roof behavior and is a combination of loads produced from convergence of the main roof and displacements of the immediate roof caused by deformations of the cantilevered roof beam. Since the shield stiffness remains constant for all leg pressures and main roof convergence is irresistible in terms of shield capacity, the shield must be able to control the behavior of the immediate roof or floor structure for shield loading to be sensitive to setting pressures. If the goal is to minimize total shield loading, any active setting force must be offset by reduced passive shield loading to justify the active setting loads. Field data sumest that the typical reductions in passive loading do not justify the required increases in setting pressure in some applications.

Jan 1, 2010

By Richard J. Mainiero

The Bureau of Mines has developed a prototype nonincendive explosive rock-breaker charge that can be fired unconfined in underground bituminous coal mines without the danger of igniting a flammable atmosphere that might be present. At present, unconfined shooting in underground coal mines is prohibited, but there are situations where the use of such shots would yield an overall improvement in safety. The charge consists of 1-1/2 lb of permissible water gel explosive in the form of a short cylinder 7 inches in diameter and 7/8 inches high, surrounded by a 1 1/2-inch-thick layer of damp salt, and encased in latex rubber reinforced with cheese cloth. The latex rubber housing provides a charge package that is strong enough to resist rough handling yet is pliable enough to conform to an irregular stone surface. A charge of this shape was found to be more effective at breaking rock than charges with lined or unlined cavities. Incendivity tests in a gallery have shown that the prototype charge will not ignite a flammable methane-air atmosphere when fired. Rock- breaking tests made with limestone boulders indicate that the charge will satisfactorily break stone slabs weighing 1 to 2 tons, and that two or more charges might be effective for slabs weighing up to 10 tons. In cooperation with the Mine Safety and Health Administration (MSHA), a test protocol for the certification of these charges as "permissible" for use in flammable atmospheres is being developed.

Jan 1, 1982

By A. J. Fejes

The purpose of this Bureau of Mines report is to provide mining industry personnel and regulatory authorities with a subsidence-reference list and annotated bibliography that will aid them in locating subsidence information and in developing their own subsidence information sources. Over 700 references are listed in the Bureau's subsidence information center bibliography; approximately 600 of these references were obtained for assessment. Of these 600 references, 167 were selected to be rated, categorized, and annotated. All literature referenced in this report was published prior to 1984. Table 1 is a cross - referenced index that classifies and rates selected references with respect to specific keywords. References are rated not on quality of content but rather on applicability to given subject areas. Appendix A is an annotated bibliography of the references listed in table 1 and provides further information of each article to aid the user in selecting articles for specific areas of subsidence technology. Appendix B is a copy of the subsidence information center bibliography.

Jan 1, 1985

By D. E. Hirsch

The Bureau of Mines has developed a systematic procedure for separation, characterization, and semiquantitative analysis of high-boiling (350° to 550° C) distillates of crude oils. Isothermal and molecular distillation were used to prepare the 370° to 530° C distillate of Recluse, Wyo., crude oil. The distillate was separated into fractions by chemical treatment, silica-alumina gel adsorption, and gel permeation chromatography (GPC). The fractions were analyzed by use of GPC correlations and mass and nuclear magnetic resonance (NMR) spectrometry. The increased knowledge of petroleum composition obtained from the data will contribute to improved petroleum processing and utilization and energy conservation.

Jan 1, 1974

By E. J. Gleim

Many people consider the mining of coal to be an extremely hazardous occupation; but it should be remembered that most large industries have to meet special conditions which, if not dealt with properly, might become hazards to life and property. Mining men may not always be fully aware that some practices and certain equipment that is incorrectly designed or maintained can lead to dangerous conditions. In endeavoring to help the coal-mining industry to prevent accidents and disasters, the Bureau of Mines has engaged in a program of education on conditions and practices that must be avoided. An effective way to teach safety is by visual demonstration. For example, it is generally known that certain kinds of electrical flashes have ignited explosive atmospheres in mines, but actually to see and hear explosions caused by electrical sparks of different size and character under laboratory control is likely to teach a much more emphatic and lasting lesson than would be learned by merely reading about them. The interest manifested by those who witness the demonstrations seems to prove that this is true. The purpose of the demonstrations is not to discourage the use of electricity in mines, but rather to indicate what types of equipment (including some generally regarded as harmless) can ignite gas and what safeguards have been developed to prevent such ignitions. It is hoped that this information will improve the ability of mining men to cope with underground hazards.

Jan 1, 1937

By Frank A. Peters

A series of evaluations is being made to determine the relative processing costs of producing metallurgical-grade alumina from low-grade aluminous materials. These evaluations include the estimated operating and capital costs as well as recommendations for additional research and development to improve the processes and to lower their costs. The design for each process is based on published work. The three processes considered in this evaluation are designed to leach alumina as aluminum sulfate from calcined clay with sulfuric acid and to remove the silica residue by filtration. The filtrate from leaching is then purified by one of the following methods: Removal of iron in electrolytic cells using mercury cathodes; removal of iron by chemical precipitation through the formation of an iron-manganese complex; or precipitation of the alumina from an aqueous-ethanol solution, leaving iron in solution. Both the operating and capital costs for these processes are higher than those for the Bayer process. For plants producing 1,000 tons of alumina a day, the estimated operating costs per ton of alumina are: Electrolytic iron-removal process........... $81.35 Chemical iron-.removal process............... 82.08 Ethanol purification process............... 86.17 The investment in mercury is not part of the operating cost since this cost is considered equivalent to catalyst cost which would not be shown. The estimated capital investments for 1,000- ton-per- day plants on a Marshall and Stevens chemical equipment index basis of 240.0 are: Electrolytic iron-removal process...... $116,775,500 Chemical iron-removal process............... 99,418,900 Ethanol purification process................ 94,210,200 These investments include the working capital but not the land for each of the processes. Included in the electrolytic iron-removal process is an investment of $4,859,400 for mercury. Investigation of other methods for removing iron, of the decomposition operation, and of the leaching operation could reduce these costs.

Jan 1, 1963

By R. S. Dean

[Methods s of preparing the manganese metal that has been used in chemical and metallurgical investigations have passed through a cycle. Most of the investigations made before the turn of the century, used Moissen's pyrophoric manganese.3/ This material was made by electrolysis into a mercury cathode and distillation in vacuo. The material was essentially pure, and investigations in which it was employed (with proper precautions against oxidation) led to accurate results on tie intrinsic behavior of metallic manganese.]

Jan 1, 1941

By D. E. Emerson, C. G. Kirkland, E. M. Frost

An apparatus has been developed for determining the helium content of gases containing 40 percent or more helium . It utilizes activated coconut charcoal at liquid nitrogen temperatures to adsorb constituents other than helium in the mixture . Series of analyses have been run where the mean deviation was less than 0.05 percent helium . Twenty or more analyses can be made in an 8- hour day .

Jan 1, 1964

By D. H. Carlson, J. H. Johnson

"The U.S. Bureau of Mines and Michigan Technological University (MTU) are collaborating to develop an apparatus for measuring diesel tailpipe emissions in underground mines. A tailpipe emissions measurement apparatus (EMA) is described that dilutes diesel exhaust and measures the concentrations of diesel particulate matter (DPM), CO, CO2, NO, and NO2 at known dilution ratios.The EMA was evaluated by side-by-side comparison of its measurements with those by laboratory grade instruments. Concentrations of CO and C02 measured by the EMA were usually within ± 14 pct of concentrations measured by laboratory-grade instruments for CO and ±20 pct for C02• EMA measured DPM concentrations were, on average, 29 pct lower than those measured by laboratory-grade instruments, with the differences being fairly consistent. The CO and C02 differences are related to the method of calculating the EMA's dilution ratio, and the difference in DPM concentrations is attributed to thermophoretic and/or condensation losses related to the EMA's unheated sample probe. Preliminary analysis of data obtained with a heated sampling probe and modifications in the sampling procedures have indicated reduced variability in DPM and in the calculated dilution ratios."

Mar 1, 1992

By E. J. Gleim

The construction of explosion-proof electric mine equipment for operation in gassy coal mines of the United States was begun as early as 1903. In 1.906, similar equipment with special protective devices was built for export. An investigation of explosion-proof motors was conducted by the United States Bureau of Mines during 1910 and 1911. In other words, this was among the first efforts of the Bureau directed toward the saving of life and property subsequent to its establishment by act of Congress in 1910. In these early motors, those with special devices for relief of explosion pressures predominated. At that time it was generally considered that, by providing for pressure relief, the enclosures could be made lighter in weight because of the lower explosion pressures developed within.

Jan 1, 1954

By Charles V. Jude

This U.S. Bureau of Mines report presents a review and evaluation of existing and new backfilling materials and methods for their applicability to the problem of gate road stress reduction in deep retreat longwall coal mines. Candidate backfill materials include pulverized coal combustion fly ash, flue gas desulfurization, and fluidized bed combustion by-products from coal-fired electric power generation plants. Properties of both backfill and its component materials are presented, with particular emphasis on the unconfined compressive strength and elastic modulus of backfill mixtures. Hydraulic mix designs discussed in this report include high-water content slurry and low-water content paste fills. Three gate road stress-transfer-modification concepts are proposed to reduce abutment stresses in gate road systems. The first concept, packwalling, involves packwall construction behind the headgate shield inby the face and adjacent to the headgate pillars. The second concept, gob-filling, involves infilling a strip of gob inset from and parallel to the headgate using paste injection methods patterned after a technology recently developed in Europe. In the third concept, entry-filling, slurry fill methods are used to fill abandoned gate roads and crosscut entries inby the face.

Jan 1, 1995

By Oliver Bowles

[Simple systematic accounting that adequately records all transactions has long been regarded as essential to the welfare of any business enterprise. Some of the defects that detract from the prosperity of the slate industry are attributable to a lack of effectiveness in cost keeping. This condition has promoted the United States Bureau of Mines to make a detailed study of accounting methods for the slate industry, and to present for consideration a system of accounts, which it is believe would enable the industry to attain more economical management and operation if accepted by a fair proportion of its important units. The method of accounting presented herein has been worked out with the assistance of leading slate producers and the recommendations are tentative and are submitted in this form as a means of developing constructive criticism. Believing that cooperative effort in this, as in many ether problems will bring the most enduring benefits to the industry as a whole, the writer urges that the cost earnest consideration be given to this vital problem now facing the slate industry.]

Jan 1, 1929