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By A. C. Smith

The U.S. Bureau of Mines developed an experimental method to evaluate the relative effectiveness of water additives on the extinguishment of coal fires. The experiments were conducted in the fire zone of the multiple-entry section of the Bureau's Bruceton Experimental Mine. Four-hundred-pound Pittsburgh Seam coalbeds were ignited and allowed to burn until well-developed fires were achieved. Extinguishing agent-water solutions were then applied to the fires, and the quantity required to extinguish the fires was compared with the quantity of water alone required to extinguish similar fires. A 20% diammonium phosphate-water solution required an average of 5.8 gal to extinguish the coal fires, while two commercially available additive-water solutions required an average of 8.1 and 8.0 gal, respectively. The average amount of water required to extinguish the fires was 7.4 gal. An analysis of covariance, using the thermal energy of the coalbed to quantify the fire at the time of extinguishment, showed that the diammonium phosphate-water solution was slightly more effective at extinguishing these coal fires than water alone, and the two commercially available additive-water solutions were statistically equivalent to water alone.

Jan 1, 2010

By Joseph A. DeCarlo

According to the annual survey of beehive-coke plants by the Bureau of Mines, United States Department of the Interior, there were 61 plants with 9,549 ovens in the United States on December 31, 1956, This publication in¬cludes only those for which an annual report was filed with the Bureau of Mines. Not all plants listed were active, however, as nearly one-third of those canvassed were idle all year. A compilation of the returns showed that 44 plants with 6,920 ovens were active part or all year and 17 plants with 2,629 ovens were idle throughout the year. The capacity of beehive ovens has fluctuated between 6 and 14 million tons during the past decade. At the end of 1956, the annual coke capacity of beehive ovens on which reports were received amounted to 5.8 million tons. As noted in table 2, however, not all of this capacity was in operating condition, as 2,093 ovens with a capacity of 1.2 million tons were not operable on [ember] 31, 1956.

Jan 1, 1958

By J. Croeni

The search for new alloys for application in the atomic energy field had prompted investigation of zirconium-rare earth metal alloys by the Federal Bureau of Mines. In this instance the zirconium-dysprosium system was investigated by melting point, thermal analysis, resistivity, X-ray and metallographic methods. Results indicate a single eutectic system with a peritectoid reaction occurring at 890° C. The eutectic isotherm extends from 30 to 95-percent dysprosium at 1,280° C. Eutectic composition is located at approximately 70 percent dysprosium. Solid solubility of dysprosium in both alpha and beta zirconium is extensive. The extent of solid solubility of zirconium in dysprosium has not been determined. Although zirconium rich alloys exhibit a significant increase in hardness, they can be cold worked extensively. These alloys also appear adaptable to solution heat treatment. Additional investigations concerning corrosion resistance and other mechanical properties are necessary for satisfactory evaluation of these alloys. The superior corrosion resistance of zirconium and the nuclear cross-section characteristics of the rare earth metals have stimulated alloy investigations using zirconium as a base metal. Alloys combining these characteristics present a possible substitute for hafnium as a control rod material. In this particular study dysprosium was chosen as the alloying element, and several series of alloys were used to establish the equilibrium diagram.

Jan 1, 1960

A revolutionary development in blasting materials has occurred in recent years. Ammonium nitrate, sensitized by the addition of a small percentage of No. (class) 2 diesel fuel or other suitable petroleum product, has been adopted as a low-cost, efficient blasting agent2 in a wide variety of mining, quarrying, and heavy construction operations. Moreover, the ready availability of the component supplies throughout the Nation, together with the ease of formulating them into effective blasting agents, has made it possible for the blaster himself to prepare the mixes at the site of use. Recently, most established explosives manufacturers have begun supplying premixed AN-FO (ammonium nitrate-fuel oil) or a comparable product to various mining operations. However, many individuals and small business establishments are marketing premixed products prepared in facilities that are often poorly constructed and poorly located. Although these blasting agents have partly or wholly displaced explosives such as dynamites in many applications, there are some blasting operations in which the fuel-sensitized ammonium nitrate agents do not appear to be well adapted. As long as the hazards they present are clearly understood and respected, ammonium nitrate-based blasting agents have important safety characteristics when prepared under competent factory control or field-mixed under equivalent close control. This publication attempts to summarize the knowledge of those hazards and to incorporate practical ways to cope with them.

Jan 1, 1963

By W. N. Marchant

The Bureau of Mines performed chemical research to elaborate details of sulfur chemistry pertaining to the citrate flue gas desulfurization process in which sulfur dioxide (SO2), absorbed (as bisulfite ion) in a buffered sodium citrate solution, is reduced by hydrogen sulfide (H2S) according to the overall reaction 2H2S + HSO3 + H+ ? 3S + 3H20. The rate-limiting step in the process was shown to be the reduction by H2S of thiosulfate (S2031-) that is formed as an intermediate. Pseudo first-order kinetic measurements were made at room temperature to retard the reaction sufficiently that adequate analysis was possible. These measurements showed the rates of the following net processes to be -d [S02]/dt (pH 4.5) = (0.409±0.050)min-1 [S02]; d [S2032-]/dt (pH 4.5) = (0.199±0.017)min-1 [S02]; -d [S2032-]/dt (pH 4.0) = (0.0437±0.0265)min-1 [S2032-]~1; -dH2S/dt (pH 3.9) = (21.6±3.0) mmoles/min-atm [H2S]g1.4, where [H2S]g is the partial pressure of H2S in the gas phase, in atmospheres, and the rate describes the consumption of H2S, in millimoles per minute; d[S]/dt (pH 4.0) = (38.0±3.4)min-1 [H2S]1, where [H2S] is the concentration of H2S in solution. Hydrogen ion consumption during the slow phase of regeneration was shown to occur at (2.1±0.5) times he rate of thiosulfate consumption, which is interpreted as evidence for the following as the rate-limiting reaction: 2H2S + S2032- + 2H+ ? 4S + 3H20 A scheme consisting of five sequential general reactions is proposed to account for sulfur formation.

Jan 1, 1981

By S. P. Kinney

The efficient operation of a blast furnace is primarily dependent upon efficient contact between the descending stream of solid materials and the ascending stream of gas. The United States Bureau of dines is conducting a program of research dealing with the interior of the present-day furnace. The work is being carried oat by.(1) observations on commercial furnaces end (2) experiments in the laboratory. Through the courtesy of the officials of the Illinois Steel Co. it was possible to make a detailed investigation of the interior of the shaft of Number.4 furnace at the company's South Works, South Chicago, Ill. The experimental work is to be reported in a U. S. Bureau of Mines bulletin which will include the results of several thousand observations on the interior of the shaft of this furnace. Such of the data as are presented later in this paper constitute only a brief summary.

Jan 1, 1929

By M. Hayashi

The Bureau of Mines conducted laboratory studies on Idaho mudstones to examine techniques for extracting vanadium. Recovery of vanadium from low-grade sources could contribute to future vanadium production and reduce reliance on imports. An Idaho mudstone surface sample containing 0.30 pct V205 and an underground sample containing 0.21 pct V205 were used in the extraction tests. Leaching of the surface sample for 18 h at 800 C with the addition of up to 1,000 lb/ton H2S04 recovered 70 pct of the vanadium. How-ever, leaching of the underground sample under the same conditions re-covered only 47 pct. By adding 15 wt pct NaCl and roasting the samples at 7500 C for 2 h, followed by leaching with 800 lb/ton H2S04, vanadium extractions were increased to 78 pct from the surface sample and 83 pct from the underground sample. Water leaching of samples roasted at 7500 C for 4 h with a 25-wt-pct NaCI addition yielded about 60 pct of the vanadium from both surface and underground samples. Autoclave leaching at 2000 C for 3 h with 1,000 Ib/ton H2S04 extracted 97 pct of the vanadium from the surface sample and 86 pct from the underground sample. An exploratory solvent extraction investigation to purify and concentrate vanadium in the leach solution using several organic reagents was also conducted.

Jan 1, 1985

By Charles D. Litton

This Bureau of Mines report presents a discussion of the essential components of pneumatic monitoring systems and their associated functions. Design criteria are presented which can be used for the design and fabrication of pneumatic monitoring systems having total system response times on the order of 15 to 30 min. To illustrate the utility of these design criteria, two detailed design examples are presented,

Jan 1, 1983

A revolutionary development in blasting materials has occurred in recent years. Ammonium nitrate, sensitized by the addition of a small percentage of No. (class) 2 diesel fuel or other suitable petroleum product, has been adopted as a low-cost, efficient blasting agent2 in a wide variety of mining, quarrying, and heavy construction operations. Moreover, the ready availability of the component supplies throughout the Nation, together with the ease of formulating them into effective blasting agents, has made it possible for the blaster himself to prepare the mixes at the site of use. Recently, most established explosives manufacturers have begun supplying premixed AN-FO (ammonium nitrate-fuel oil) or a comparable product to various mining operations. However, many individuals and small business establishments are marketing premixed products prepared in facilities that are often poorly constructed and poorly located. Although these blasting agents have partly or wholly displaced explosives such as dynamites in many applications, there are some blasting operations in which the fuel-sensitized ammonium nitrate agents do not appear to be well adapted. As long as the hazards they present are clearly understood and respected, ammonium nitrate-based blasting agents have important safety characteristics when prepared under competent factory control or field-mixed under equivalent close control. This publication attempts to summarize the knowledge of those hazards and to incorporate practical ways to cope with them.

Jan 1, 1963

By A. D. Garman

This paper presents one of a series of digests of foreign mining legisla- tion and court, decisions which is being prepared in advance of a general report relative to the right of American citizens to explore for minerals and to own and operate mines in various foreign countries. This interpretation of the laws of Latin America has been prepared from the best available information in Washington, but is released subject to correction and amplification, if necessary, by the proper American diplomatic and consular officers, to whom it is being referred through the courtesy of the Department of State. Individual abstracts of the laws of each of the countries herein discussed have been prepared and published separately. This general summary is presented for the use of mining engineers and investors whose interests extend over the borders of a single country. It is also designed to bring out certain general principles of mining law and, so far as feasible, to indicate the trend of mining legislation in South and Central America. In order to gain perspective, the details of legislation are not com- pletely covered in this paper, but an effort has been made to bring out essential differences as well as points of similarity in the laws of the various countries. The course of legislation is first traced chronologically and the points discussed are then arranged in tables in somerhat greater detail. .Si. With a very few exceptions the existing mining legislation of Spanish America is a development, of the Spanish "Law Decree of Bases" (more briefly referr- ed to as the "Decree-Bases") of 1868. This in turn was influenced, particularly in its classification of minerals, by the French law of April 21, 1810.

Jul 1, 1930

By R. V. Lundquist

This report describes results of tests on the desilication of solutions resulting from the leaching of lime-soda sinters. Desilication was accomplished by heating the solutions in an autoclave. A liquor relatively free of silica was obtained after 30 minutes of heating at 200 p.s.i.g. in the presence of lime. The addition of lime improved desilication, but the rate and efficiency of desilication was effected by the quality of lime used. The optimum quantity of lime for effective desilication was about 6 grams per liter. A lesser quantity gave poorer desilication, and a greater quantity increased the alumina loss without improving desilication. The alumina loss was approximately proportional to the lime added. A complex structure, called artificial noselite in this report, was the only silica bearing compound detected in the desilication precipitate. Other compounds present were Ca(OH)2 (calcium hydroxide), CaCO3 (calcium carbonate), and Ca [A1(OH)6]2 (hydrated tricalcium aluminate). Sodium carbonate in the leach liquor retarded the formation of the calcium aluminate; hence it decreased the alumina lost to the precipitate. The extraction of alumina from aluminum silicate materials by the limestone soda-sinter process has been investigated by the Bureau of Mines for many years. The process consists of the following major operations: Blending the aluminum silicate with limestone and soda ash in such proportions that dicalcium silicate and sodium aluminate are formed on sintering; leaching the sinter in a carbonated caustic solution to extract the soluble alumina; purifying the leach liquor by the precipitation of soluble silica (this precipitate is designated desilication precipitate in this paper); precipitating alumina trihydrate from the purified liquors by carbonating with carbon dioxide gas; and calcining the trihydrate to alumina. Commercial grades of

Jan 1, 1962

By Kung-Lee Wang

This Bureau of Mines study illustrates the economic significance of the Florida phosphate industry to the State and to the Nation. Environmental considerations related to phosphate industry activity are discussed briefly. Based on forecasts of Florida phosphate production in 1975, and using 1972 dollars, regional and national output value, income, and employment created by the phosphate industry were estimated for 1975. State and Federal government tax revenues generated by the phosphate industry, are also measured. Further, the concentrated impact of the phosphate industry on certain Florida areas and on regional industries is examined. Finally, the phosphate industry's importance to the U.S. balance of payments, U.S. agricultural production, and the Frasch sulfur industry is considered, in addition to byproduct fluorine, and potential byproduct uranium from fertilizer manufacturing.

Jan 1, 1974

By R. A. Bloomfield

This report summarizes Bureau of Mines contract research on the disposal of retorted oil shale. A data base has been developed describing the physical-chemical properties, geotechnical engineering properties, and natural cementation characteristics of spent shale. Results of field compaction tests and seepage pond tests are presented, along with results of a partially saturated finite element seepage model used to predict infiltration and seepage rates. Preliminary engineering analyses are presented for underground disposal systems, which include material transport methods, and for a surface disposal system, which includes stability analyses.

Jan 1, 1981

By Albert J. Rambosek

The results obtained in a study of the stress conditions existing in a drill bit-point area and in the underlying rock, when the bit was in full but nonpenetrative contact with the rock, are presented. This investigation by the Bureau of Mines was the preliminary exploratory phase of a long-range program of research on rock drilling to establish criteria for the maximum economically feasible rate of rock penetration. The photoelastic technique of experimental stress analysis was the principal method used to obtain the data. Transparent models and transmitted light were employed to investigate patterns in drill-bit models and isotropic materials under the bit when subjected to a concentrated static load. Comparative stress data for anisotropic rock were obtained by the reflective photoelastic technique. Brittle lacquer and an extensometer were used obtain supplementary information wherever substantiating data were desired to check photoelastic results. The zone of maximum shear occurs along an arc near the contact face of the bit. The stress distribution pattern in an isotropic model rock near the area contacted by the bit was nearly a mirror image of that exhibited within a similar areal zone of the bit. The stress pattern in granodiorite specimens was similar, though not symmetric, to the pattern in the isotropic model rock. The asymmetry of the stress pattern in the granodiorite was attributed to the anisotropic characteristics of the constituent minerals of various sizes.

Jan 1, 1963

By Bernadette Michalski

Although hydrocarbons accounted for more than 60% of Bahrain's income and more than 80% of export earnings, this island nation sustained one of the more diversified economies in the Gulf Region. The availability of low-cost natural gas for electric power has fostered the development of a significant aluminum refining and manufacturing industry with emphasis on vertical integration. The Bahraini iron pelletization plant, closed since 1986 due to financial problems, was scheduled to reopen by early 1989. Commodity Review Metals.-Aluminum.-Aluminium Bah-rain Bsc (Alba) attained record high production levels in 1988 taking advantage of favorable aluminum prices, which averaged over $2,000 per ton as compared with less than $1,500 per ton in 1987. Net aluminum production was nearly 13,000 tons over design capacity. Fewer standard ingots (52,081 tons as compared with 79,685 in 1987) were produced as Alba concentrated on higher value added products such as rolling ingots (42,324 tons as compared with 32,125 tons) and extrusion billets (60,934 tons as compared with 46,618 tons).

Jan 1, 1990

By B. I. Ferber

Sodium chloride aerosol was employed to determine respirator filter penetration in a manner suitable for use in Bureau of Mines approval and certification procedures. The aerosol was produced by an ultrasonic generator and treated to yield the proper conditions of relative humidity, particle size, and concentration. Respirator filters were exposed to the aerosol; filter penetration (down to 0.02 percent) was determined with a flame photometer. Results are comparable with those obtained in another laboratory using different equipment.

Jan 1, 1970

This final report summarizes the effort on a very aggressively scheduled and demanding development program undertaken by Westinghouse for the U.S. Bureau of Mines under Contract No. H0101262. The objective of this program was to produce hardware and test it to determine the efficacy of certain concepts of Coal Mine Rescue and Survival as established by the request for proposal and the study performed for the U.S. Bureau of Mines by the National Academy of Engineering (NAE). (These are stated in paragraph 1. 1 for reference.) In carrying out this program, Westinghouse provided specific hardware designs in consonance with the objectives of the concepts outlined in the NAE study final report. Though this contract did not require producing final design hardware ready for introduction to the coal mining community, components of the CMR&SS - as delivered - have some value in disaster situations and are to be kept on standby alert. Additional design and production development is required and should be undertaken on most of the subsystems and components before they can be used in the competitive coal mining community.

Jan 1, 1971

By R. S. Dean

A general survey of the metallurgical work of the U. S. Bureau of Mines has been given in an article in the Missouri School of Mines Alumnus, and a somewhat more detailed review of the bureau work on lead and zinc will be found in the Mining Congress Journal. C. C. Furnas has contributed one general mathematical article. Dean, R. S. U. S. Bureau of Mines. 4, 1930, pp. 7-8. Program of Metallurgical Investigations of the Missouri School of Mines Alumnus, vol. 4, No. Investigations of the U. S. Bureau of Mines on the Milling and Smelting of Lead and Zinc. Min. Cong. Jour., vol. 16, 1930, p. 799, 808. Furnas, C. c. Evaluation of the Modified Bessel Function of Am. Mathematical Monthly, vol. 37, the First Kind and Zeroth Order. No. 6, 1930, pp. 282-287.

Apr 1, 1931

By Charles S. Allbright, Frank G. Schwartz, Marvin L. Whisman

Radioactive tracer techniques were used to gain a better knowledge of the types of compounds that cause gum formation in gasoline during storage . A selected organic compound was labeled with tritium and purified . An unstable gasoline was tagged by adding a small amount of the labeled compound . After storage of the gasoline at 110 ° F for 16 weeks , the gum that had formed was recovered . The amount of the test compound converted to gum was determined by liquid scintillation counting . About 70 compounds , including several classes and types , were studied . The compounds , listed in order of descending reactivity in the test fuel , were sulfur compounds , nitrogen compounds , polycyclic hydrocarbons , olefins , alkylbenzenes , and saturates . In the order of decreasing percentage of each in the gum , the compounds were monoolefins , alkylbenzenes , sulfur compounds , polycyclic hydrocarbons , nitrogen compounds , and diolefins . This type of information should be helpful in developing a method for predicting the storage stability of gasoline .

Jan 1, 1964

By Lito C. Mejia

Diesel-powered equipment operating in a gassy underground mine could conceivably ingest a methane-air mixture from the mine atmosphere that could cause the diesel engine to overspeed, or exceed its rated speed. Engine overspeed, particularly if extreme (engine runaway), could result in personal injury, a possible mine explosion, and/or catastrophic engine failure. In this report, the Bureau of Mines reviews the literature on the potential hazards of methane-induced diesel engine overspeed. Also included are the Bureau's findings from consultations with representatives of the diesel engine industry to determine the specific engine behavior that could he expected under the overspeed condition. The report summarizes data on mine accidents involving methane, discusses results of tests on the compression ignition of methane in diesel engines, and examines fuel governors and intake-air-cutoff devices, two kinds of devices used to prevent overspeed. Analysis of the information gathered suggests that the conditions necessary to cause a diesel engine to overspeed uncontrollably are not likely to occur, particularly if the engine is equipped with flame-proofing devices. The available literature and lack of actual overspeed case histories suggest that the safety devices currently in use are sufficient to prevent diesel engine overspeed.

Jan 1, 1984