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By J. J. de Barbadillo

This report describes a process for recovering chromium and other metals from superalloy scrap. Part I contains the results of laboratory scale experiments which were conducted to test a complex flowsheet utilizing a wide range of extractive metallurgical operations. The novel basis for the process is the formation of a sulfide matte in which chromium is concentrated in a discrete chromium sulfide phase. Mineral processing and hydrometallugical procedures are used to separate chromium sulfide from the other matte constituents. The products of the process are a chromium-nickel alloy suitable for reuse in the superalloy industry, electrolytic nickel, electrolytic cobalt, and an iron-molybdenum residue. Recovery of the principal elements contained in the scrap are chromium(Cr)-93 percent, nickel(Ni)-99 percent, cobalt(Co)-96 percent, molybdenum(Mo)-92 percent. Part II encompasses a preliminary engineering design of a pilot plant capable of treating 100 pounds(lb) of superalloy scrap per hour. Also included is an economic analysis of the operation of the pilot plant.

Jan 1, 1980

By Horace C. Porter, F. K. OVITZ

Much has been written of the changes undergone by coal in storage and the deterioration of coal through exposure to the weather. In order to obtain definite information for the benefit of the Government departments and of all who store coal in large quantitieS', a series . of tests was begun in the fall of 1909 under the supervision of tT. A. Holmes, then chief technologist of the United States Geological Survey, and was continued by the Bureau of Mines after its establishment in 1910. The tests were confined to determinations of the loss in heating value of the coals and did not include a study of other deterioration; for exaIp.ple, in coking quality or the yield of by-products in coking. The Bureau of Yards and Docks of the Navy Department cooperated in tests of New R~ver (W. Va.) coal, a variety largely used by the Navy. A preliminary report presenting a brief account of the early results of these tests has been published by the Bureau of Mines as Technical Paper 16.a The detailed report is presented in this bulletin, which gives a fu11 account of the tests and the analytical data covering a period of five years' storage. Data of somewhat similar experiments for shorter periods with gas coal from the Pittsburgh bed, with Pocahontas coal on the Isthmus of Panama, and with Sheridan, Wyo., subbituminous coal, which is used for railroad and other purposes in the West, are included. The tests of New River coal, in cooperation with the Navy Department, were undertaken to determine the advantage to be gained by storing coal under water, and particularly under salt water. Small lots were used in order to make the tests of maximum severity, and parallel experiments were made with run-of-mine and crushed coal under one-fourth inch size. All of the small lots tested under the different conditions (except those tested near Key West, Fla.) were taken as representative portions from one large original lot. The tests of Pocahontas coal, which, like the New River, is semibituminous, were undertaken chiefly to determine th.e effect of the tropical conditions in Panama. They were made on an outdoor pile of 100 tons of run-of-mine coal. Pittsburgh gas coal, a high-volatile, bituminous type used at gas and by-product coke works, was exposed for test at Ann Arbor, Mich., in cooperation with the University of Michigan. The university agreed to make tests at successive intervals of storage to determine, in its illuminating-gas experiment station, the yields of gas and byproducts from the coal. The coal, screened lump, was stored in about 4-ton lots out of doors in open bins. Subbituminous coal, which is mined in Colorado, Wyoming, and other States, and is known also as "black lignite," is commonly supposed to deteriorate rapidly in storage, especially by "slacking" or crumbling of the lumps. The tests herein described were undertaken at Sheridan, Wyo., in cooperation with the Chicago, Burlington & Quincy Railroad Co., in order to determine the extent of this slacking and the accompanying loss of heat value. The tests were in open bins holding 4 to 12 tons.

Jan 1, 1917

By P. R. Jones

A computer program was written for design and cost of a shell and tube heat exchanger in which the total cost, which includes annual fixed charges and annual operating costs, was minimized. The program was written for the type of heat exchanger in which only the tube side pumping costs were significant and for triangular pitch, single or multiple pass, heating or cooling, and no change in phase. Tube diameter was not optimized since the tube dimensions do not affect the cost very much. However, the tube dimensions do affect the shell diameter, number of tubes, and length of tubes; and price optimum design was obtained for four standard tube diameters. Standard heat exchangers having at least the required area are also listed. The program was made adaptable to various fluids and to various tube dimensions by including many of the required data such as physical properties of the fluids, tube data, and standard shell data as input data.

Jan 1, 1969

By Joseph Coffman

There are 14 operations that supply 97% of the Market Economy Country (MEC) manganese and contain nearly all of its resources. Six mines account for about 70% of the production and 85% of the resources; there are no known resources that are economically close to those that are currently being mined. Costs (January 1989 dollars) of producing manganese concentrates from the operations evaluated are estimated to range from $ 0.96 to $ 1.86 per long ton unit (ltu or 22.4 lb) of contained manganese. Total MEC demonstrated resources evaluated amount to about 1.2 billion tons of in situ ore containing 474 million tons of manganese. Identified resources amount to about 1.8 billion tons of in situ material. Key results of the study indicate the following: 1. The MEC supply of manganese will be from the currently mined resources well into the next century. 2. Centrally Planned Economy Countries (CPEC's) will be increasingly dependent on MEC manganese ore and concentrate in the future. 3. At the 1976 to 1987 demand increase rate, total MEC resource needed through the year 2000 would be about 282 million tons of in situ material. 4. Transportation and infrastructure support will continue to be major elements of production costs.

Jan 1, 1992

By D. R. Tesarik

As part of its research program to investigate ways of improving resource recovery and reducing subsidence, researchers from the U.S. Bureau of Mines placed instruments in the B-North ore body of the Cannon Mine, Wenatchee, WA, to monitor cemented backfill and rock deformation during mining. The vibrating-wire gauges proved to be reliable and versatile, and approximately half of the instruments are providing data after 2 years of use. A two-dimensional, finite-element model was used to analyze the Cannon Mine's multilevel bench cut-and-fill mining method and predict rock and backfill displacements. The model accurately predicted rock displacements, but the predicted and measured displacements in cemented backfill had a correlation coefficient near zero, indicating that the model should only be used to predict rock displacements and not backfill displacements. A finite-difference model was also used to evaluate the stability of a cemented backfill pillar. Results can be used to conservatively predict backfill stresses, but on-site observation of pillar failures coupled with in situ measurements are needed to make more accurate predictions. An ongoing evaluation of the mining system has indicated that filling the primary stopes tight to the back with cemented backfill allowed these pillars to carry overburden loads soon after the cemented backfill was placed.

Jan 1, 2010

By A. M. Poston

Introduction of radioactive elements into ore samples and/or pregnant liquors and radiometric tracing thereof have greatly improved control of fusion and extraction studies on beryllium ores and products. Extractive metallurgical research on beryllium, normally guided by the usual laborious analytical methods, is both costly and slow. Recognition of this problem by the Bureau of Mines led to the development and application of radioisotope tracer techniques" as a substitute for chemical analysis at the Salt Lake City Metallurgy Research Center, The result was that much faster progress at significantly lower cost was achieved. This report discusses the problems encountered and resolved in using radioactive tracers and radiometric methods, defines the conditions and techniques for their effective use, and delineates the limitations and flexibility inherent in applying such methods in laboratory-scale beryllium research.

Jan 1, 1962

By R. S. Rosso

A program to investigate the effects of hardened washers on the uniformity of roof bolt tension and the resulting ground control in an underground mine was carried out. The complete roof bolt installation and roof bolt loads, mine convergence, and bed separation were monitored for a period of five months. The results show no evidence to support or refute the theory that mechanical roof bolts offer better support when they are installed with a high uniformity of tension. Also shown is the fact that if the bolts are installed with a maximum deviation from the mean torque of ±15% the addition of hardened washers significantly improved the uniformity of the installed tensions in the roof bolts.

Jan 1, 1977

By Albert L. Toenges

(1) The Castleman Basin was investigated by diamond drilling, engineering examination, and geologic study. Agreements permitting investigation of about 14,700 acres of land were entered into with 79 landowners. Eleven beds of coal between the horizons of the Harlem and Mercer beds were penetrated in drilling. These beds from top downward are: Harlem, Upper Bakerstown, Lower Bakerstown, Brush Creek, Upper Freeport Rider, Upper Freeport, Upper Kittanning, Middle Kittanning, Lower Kittanning, Mount Savage, and Mercer. The total estimated reserves of coal (measured, indicated, and inferred), 14 inches or more thick, in six beds follow: [Coal bed: Etimated reserves, tons Harlem _______________________ 23,430,000 Lower Bakerstown _______________ 44, 688, 000 Brush Creek ____________________ 23, 694, 000 Upper Freeport __________________57, 731, 000 Upper Kittanning ________________ 40, 450, 000 Middle Kittanning ______________42,276,000 Total________________________ 232,269,000]

Jan 1, 1952

By T. H. Jeffers

The Bureau of Mines conducted a laboratory investigation of copper electrowinning from electrolytes produced by solvent extraction. The purpose of the research was to gain a better understanding of the fundamental relationship between copper electrowinning conditions, anode corrosion, and cathode purity. Processing variables were evaluated in a cyclic semicontinuous system in which the depleted electrolyte was used to strip copper from loaded organic extractant. For the production of high quality copper cathodes, the electrolyte was dosed with cobalt and stripped of organic solvent extraction reagent. An optimum cobalt addition of 60 ppm, and removal of the entrained extractant with activated carbon provided the best conditions for electrowinning copper containing the least amount of lead and controlling anode corrosion. As little as 13 ppm of the entrained organic extractant, LIX 64-N, significantly accelerated anode corro-sion. However, the addition of 1,000 ppm of organic diluent kerosine did not affect anode corrosion. After cobalt dosing and removing the entrained extractant, cathodes containing less than 2 ppm lead were consistently electrowon at widely varied current densities, electrolyte copper and acid concentrations, and temperatures. Dosing of the electrolyte with selected impurities including magnesium, aluminum, manganese, and iron did not affect the cathode purity. However, 0.05 giL of chloride ions markedly increased anode corrosion and the sub-sequent transfer of lead to the cathode copper.

Jan 1, 1985

By W. A. SLOAN, G. L. Oldright, J. D. Sullivan, E. K. PRYOR, A. F. HALLET, R. S. Dean, S. L. BROWN, F. S. Wartman, A. J. Thompson

Lack of sufficient publication funds has resulted in the accumulation of considerable unpublished experimental work on copper metallurgy by the Bureau staff . The present report gives extended abstracts of this work , as well as a discussion of the best direction for future efforts . The experimental work reported in this series of papers was done in cooperation with the University of Arizona , Tucson , Ariz . The investigations covered in the third , fifth , and seventh papers were done under the direction of G. L. Oldright and the remainder under the direction of V. H. Gottschalk .

May 1, 1934

By N. S. Dalal, X. Shi

"Electron spin resonance (ESR) spectroscopy has been employed to· examine the role of tetraperoxochromate( V) ions (Cro:-) and other Cr(V) species in the generation of hydroxyl (OH) radicals in the reaction of Cr(VI) with H2O 2 in biological media. In contrast to earlier suggestions, the present ESR studies using crystalline K3CrO8 as a source of Cro:- show that decomposition of Cro:- in water or in H2O 2 does not generate significant amounts of OH radicals. Addition of NADH to a solution containing Cro:- yields a Cr(V)-NADH complex, which readily reacts with H2O 2 to generate OH radicals. Similar results obtained from several other biological reductants, including vitamin B2 , indicate that a vacant coordination site on a Cr(V) complex facilitates its reaction with H2O 2 to generate ""OH radicals. We thus suggest that in biological media, reaction [3] instead of [1] or [2] is the major pathway for the OH radical generation: While the carcinogenic potential of Cr(Vl)-based compounds has been well established via epidemiologic and animal studies (1), the underlying biochemical mechanism is still not well understood (2). In a recent development, however, Kawanishi et al. (3) have reported that hydroxyl (OH)2 radicals might be the key species in the mechanism of Cr(VI) toxicity. As to the mechanism of the ""OH radical formation they suggest that Cr(VI) reacts with cellular hydrogen peroxide (H2O 2) to form the tetraperoxochromate(V) (Crog-) ions, which decompose to produce hydroxyl radicals. It was also suggested (3) that the ""OH radicals thus produced cause genotoxicity via DNA base modification and deoxyribose phosphate backbone alterations. More recently Aiyar et al. (4) reported the detection of OH radicals in the reaction of Cr(VI) with H2O 2 in biological media, including the reaction of ""OH radicals with deoxyguanosine to generate 8-hydroxydeoxyguanosine adducts, confirming that ""OH radicals could indeed play a significant role in the mechanism of Cr(VI) toxicity. However, the mechanism for the ""OH generation was not clarified, although the role of Crog- ions as possible precursors was mentioned, somewhat along the lines suggested by Kawanishi et al. (3). The possibility of the participation of Crog- in the ""OH generation has also been indicated by Sugiyama et al. (5), since they mention that vitamin B2 enhances the formation of""OH radicals in the reaction of Cr(VI) with H2O 2 because of the generation of Crog- in the reaction."

Jan 1, 1990

By D. R. Tweeton

The U.S. Bureau of Mines has developed tomographic computer programs for geophysical applications and is distributing them as part of a Bureau plan to facilitate the transfer of technology to potential users. These programs were developed for predicting and monitoring the flow pattern of leach solution during in situ mining. The Bureau has also applied them to assessing high-wall blast damage and examining the integrity of mine-related geological structures. This report describes the curved ray program BOMCMTR (Bureau of Mines curved ray tomographic reconstruction), tells how to run it, and gives examples with synthetic and field data. BOMCRATR provides optional mathematical constraints to counteract the nonuniqueness of tomographic reconstructions with crosshole data. These constraints include limiting the maximum and minimum velocities, fixing the velocity at any point to any value, and establishing layers in which velocity does not vary with horizontal position. The user can test for nonuniqueness by varying the initial velocity pattern, The program can perform either curved or straight ray analysis. Ray paths are calculated analytically in triangular pixels, which is faster than incremental numerical approximations,

Jan 1, 2010

By Robert F. Chaiken

Burnout Control is a process developed by the U.S. Bureau of Mines for accelerating the burning of wasted coal fires in situ, while at the same time controlling the heat and fumes produced. The Albright fIre project is a fIrst fIeld trial of Burnout Control as applied to a coal waste bank. An exhaust ventilation system was designed and constructed and then operated over a 1-year period at the site of an existing abandoned mine land fire near the town of Albright, WV. While predicted exhaust gas temperatures of 900° C and thermal power levels of 5 MW were achieved at 20-to 3O-in H20 vacuum levels, problems were encountered with engineering designs, equipment breakdown, and fuel-rich combustion that curtailed the time period of satisfactory operation. Effective afterburning of the exhaust gases (as they were drawn from the bank) corrected the problems associated with combustion stoichiometry and led to high thermal outputs. It is believed that with (1) improvements in engineering design and construction, (2) better control of the afterburning process, and (3) the use of conventional stack gas air-pollution controls, Burnout Control can be applied successfully to a coal waste bank fire.

Jan 1, 1991

By Robert D. Saltsman

Two modes of seal application were identified, and promising state-of-the-art seals of both types -shaft and drum -were selected for initial rating by non-destructive testing. Only one shaft seal survived the initial test, and a search was made for other candidate seals including new seals. One new type of seal was found that gave promising enough operation, as both a shaft and drum seal, to be recommended for installation in prototype wet-head machines.

Jan 1, 1975

By L. Bruce McDonald

This Federal Bureau of Mines publication is a statistical analysis of all surface and underground coal mine fires reported in the United States from 1950 to 1977. Accounts of selected nonreportable fires and opinion data gathered via interviews with mine safety directors were separately analyzed. Both reported and nonreportable fires were analyzed by time trends, State, ignition source, burning substance, location in mine, equipment, detection, duration, injuries, fatalities, and successful extinguishing agents. It was found that the majority of all mine fires were electrical in origin. The equipment most frequently involved in underground fires was conveyor belts, and in surface fires, it was crushers and/or breakers. Underground fires occurred most often near the working face. Water and hand-portable extinguishers were the most common methods of extinguishment.

Jan 1, 1980

By William K. Cunningham

The investigation described in this report was begun as part of the Bureau of Mines progress to develop acid processes for the extraction of alumina from low-grade bauxite and. clays. A domestic shortage of high-grade bauxite sui table for treatment by the Bayer process became acute as a result of' World War II; an intensive search for a practical acid process using lower-grade alumina-bearing raw materials was therefore warranted. The laboratory development was described in a preceding Bureau of Mines publication wherein the basic theory for the design and erection of a pilot plant maybe found. A 2-ton-per-day continuous pilot plant was constructed and successfully operated at College Park, Md., which demonstrated conclusively the chemical and mechanical feasibility of a solvent purification process for aluminum sulfate. The estimated production cost of $38.64 indicates that under present market conditions the process would not be economically feasible.

Jan 1, 1948

By W. R. Hardwick

This Information Circular describes the development of block-caving methods and practices by the Miami Copper Co. at the Miami mine in Gila County, Arizona. It is one of a series published by the Bureau of Mines on mining methods, practices, and costs in various mining districts of the United States. This report gives a history of the district and outlines early prospecting and exploration including methods of sampling and estimation of ore tonnage and value at the Miami mine. Early mining methods are described, particularly those that influenced developments in the caving method. Mine exploration, development, and operating methods for block caving are described with particular attention to those factors, physical, economic, engineering, and managerial that have improved efficiency in the mining operations over a long productive period. Extraction, ventilation, wage system, safety, water supply, power plant, and shop facilities are discussed. The last section gives a brief sumary of such costs as are available for publication.

Dec 1, 1964

By R. A. Cattell

The Bureau of Mines actively conducted a well-coordinated research pro- gram during the past fiscal year on problems dealing with the production of oil and gas, transportation of natural gas, chemistry and refining of petrole- um, thermodynamic properties of hydrocarbons, and the processing and utiliza- tion of incombustible helium gas. These particular reserach phases, compris- ing the presently scheduled activities, are integral parts of a broad program selected soon after the war as suitable for Bureau of Mines study, to meet immediate needs for specific information on petroleum and natural-gas problems of national scope. Important progress was made and many technical reports were finished during the year. Several reports were published on gas-condensate production problems, one giving the results of laboratory tests of relative merits of various steels and alloys for rosisting the corrosion that occurs in high-pressure gas- condensate wells. Research was continued, using the Bureau's windowed cell, to determine the characteristics of gas-condensate fluids, and an important paper on the phase relations of these fluids at low temperatures was published. An important part of the Bureau of Mines petroleum production research program for many yoars has been the engineering study of type oil fields. This year reports waro completed on the Lake Creek, Sheridan, and West Rod River fields, Tex.; the Atlanta field, Ark.; and the Bogge field, W.V. Othor fields under study and for which reports will be issued are the Carthage and Now Hope fields, Tex., and the Weber pool, Okla. Spocial studios to determine the characteristics of the oil-gas solutions as they exist within the native reservoir rocks have been in progress in the North Lindsay field, Okla.; the Elk Basin field, Wyo. and Mont.; and the Rangely field, Colo. The North Lindsay study brought to light several un- usual physical proporties of the oil as it is found in this deep-seated reservoir. For instance, its viscosity is less than that of water, and more than 2 barrels of the initial reservoir oil must be produced to yield 1 barrel of "stock-tank oil." In the Elk Basin and Rangoly fields the oil-gas solution varies in composition within the reservoir, depending upon structural location. Engineering studies were continued on woll spacing and on drilling fluids with special emphasis on obtaining uncontaminated cores, or coros for which the flushing action of the drilling fluid can be dotormined accurately. In connection with research on production of oil by secondary recovery methods, progress was made in studies of conditioning water for subsurface injoction, of input ratos and pressures for water-flooding oil sands, and of the selective plugging the more permeable mediurs to prevent or retard channel- ing of the injected fluid. The availability of fuels for all types of internal-combustion engines still is tho primary resoarch project in potroleum chomistry and refining. This rosearch program is subdivided into a sorios of problems under four main topics: (1) Raw-material studios; (2) relationships of fuel consumption, proporties, and performanco; (3) utilization of potroleum products; and (4) analytical mothods, which include chomical and physical property detorminations.

Dec 1, 1949

By Paul S. Goodman

This report examines the feasibility of Employee Assistance Plans for the coal industry. Three issues are examined in detail. First, the prevalence of off-the-job factors such as alcoholism, drug abuse, and marital problems are examined in a sample of miners from the eastern, midwestern, and western underground coal fields. Then data were presented that examined the link between these off-the-job factors and behaviors critical to the mines such as absenteeism and turnover. Lastly, we examined the effectiveness of the major Employee Assistance Program in underground coal mining--the HELP Program. The report contains recommendations on whether coal mining companies should implement these programs and how these programs should be designed.

Jan 1, 1986

By Lowell Stroud

Ten natural gases containing from 0.023 to 8.4 percent helium were investigated. In seven high-helium samples, the isotopic abundance of Ne21 was greater than in the atmosphere, being supplemented by 33 to 85 percent of "excess" or "radiogenic" Ne21. The ratio of He4/Ne21(rad) in these gases was evaluated and found to vary between 2.9 x 107 and 5.9 x 107 , a factor of approximately 2. Argon concentrations were determined by the isotope dilution method. The isotopic ratios of Ar40/Ar36 in the high-helium gases were from 5 to 75 times the atmospheric value, with the Ar40 being about 80 to 99 percent radiogenic in nature. The ratios of He4/Ar40(rad) in all 10 gases were evaluated and found to range from 4 to 18. The isotopic ratio of N14/N15 in four of the high-helium gases was essentially the same as in the atmosphere; in three cases it was approximately 5 percent higher than the atmospheric value of 272.0. The genesis of nitrogen and the relationship of nitrogen to helium in natural gases were reviewed and are discussed in terms of a theory for the concurrent generation of nitrogen, helium, radiogenic neon 21, and petroleum (hydrocarbon gases and liquids).

Jan 1, 1967