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By A. G. Galaitsis

This report summarizes the work performed under the USBM Contract No. J0245001. The purpose of this work was to expand and improve the scope and accuracy of the method developed under USBM Contract No. J0113056 for the prediction of the number of overexposed workers in the mining industry. A significant portion of the noise data were acquired during mine visits-that took place in the-course of this contract. These data were obtained with time-resolved dosimeters which among other things store a time history of the sampled noise for an eight hour work period. The remainder of the noise data have been obtained from MSHA files and from other BoM-sponsored projects. The report reviews the prediction model, discusses the model's assumptions and approximations, describes the function of the developed software, offers typical examples on the use of the software and includes plots of the newly acquired noise data records.

Jan 1, 1986

By John C. Machisak

THIS CHAPTER of the Minerals Yearbook (Volume III) contains overall injury experience for coal mines, both anthracite and bituminous, coke plants, petroleum and natural gas, peat, and asphalt and related bitumens (native); metal mines, their metallurgical plants, including ore-dressing plants and primary nonferrous reduction plants and refineries; nonmetal mines; nonmetal mills; sand and gravel operations; slag (iron blast-furnace) plaints; and stone quarries and their related pants. Volume I of the yearbook contains a chapter showing injury experience and employment data treated separately by metal mines, nonmetal mines, quarries and their related plants, metallurgical plants (ore-dressing plants and primary nonferrous reduction plants and refineries are shown separately), nonmetal mills, sand and gravel plants, and iron blast-furnace slag plants. Volume II contains injury and employment experience in the fuel industries (coal, coke, petroleum and natural gas, asphalt and related bitumens (native), and peat. Injury and employment data are submitted voluntarily for the mineral operations through an industry canvass made by the Bureau of Mines, except for the coal industry, whose reports are mandatory. Information published in this chapter is the result of this canvass. Figures presented in this chapter for 1961 are preliminary except for anthracite, peat, coke, petroleum and natural gas, asphalt and related bitumens, and slag. These preliminary data, with the exception of bituminous coal, are a summation of reports received by May 31, 1962, from the operators showing their injury and employment experience. Estimations of injury and employment experience are not included in these preliminary data.

Jan 1, 1962

This publication summarizes the in-house and contract research and development projects programed for fiscal year 1981 by the Bureau of Mines under its Minerals Environmental Technology activity. The document provides a mechanism for interested parties, including potential contractors, to gain insight into ongoing and projected work of the Bureau?s environmental research efforts. Research to identify and correct environmental problems associated with mining and metallurgical operations has long been an integral part of the Bureau's mission. The environmental research and demonstration activities of the Bureau were consolidate in 1979 with the formation of the Minerals Environmental Technology program, which is directed toward the elimination or reduction of environmental problems associated with the extraction and processing of minerals. Among the efforts underway are development of data and technology for assessing the potential environmental impact of minerals development, for monitoring minerals extraction operations, and for establishing viable reclamation requirements on abandoned mine lands; development and demonstration of technology 'or control of environmental disturbances during minerals extraction operations; development and demonstration of land reclamation and mine closure techniques to restore or enhance the productive use of mined lands; development of engineering techniques that incorporate state-of-the-art mining environmental technology in the design and planning of minerals extraction operations; development and demonstration of new mining systems that greatly reduce or eliminate the adverse environmental impacts of minerals extraction; and providing the technologic base for Federal, State, and local establishment of environmental standards for mining operations. Included in the minerals-processing-related work are projects to clean mineral-processing waters: demonstrate a Bureau process for scrubbing SO from powerplant stack :;as; recover dissolved minerals from process streams; stabilize discarded dusts, slags, and tailings: remove hazardous contaminates from byproduct wastes; reduce generation of waste solids; and improve metallurgical process engineering to eliminate pollution. Approximately $21 million was appropriated for this work in fiscal year 1981.

Jan 1, 1981

By John C. Machisak

INJURY and employment figures for nonmetal mines and mills in 1959 are presented in this publication. Data for nomnetal mines are presented separately from those for nonmetal mills. The Bureau of Mines is authorized to send questionnaires to the nonmetal mining industry each year requesting their voluntary submission of injury experience and employment data. The voluntary response to these requests has contributed greatly toward the promotion of safety in the industry, and every effort has been made to make the information as complete as possible.

Jan 1, 1963

By F. W. Wood

The use of consumable.-electrode arc melting as a production technology is growing. One advantageous feature of this process is that it avoids ingot contamination by soluble crucible materials by employing a chilled metal crucible. Because the thermal balance under these conditions is rather delicate and does not necessarily provide a favorable environment for solidification, catastrophic imbalances can occur. The effectiveness and mechanistic roles of various factors are mostly unknown, and more intelligent insight regarding the distribution of temperature and heat is needed. Experience has provided several pertinent observations, some of which are quite superficial. The most meaningful data have resulted from studies of molten pool shapes and sizes and from measurements of heat flow through crucible walls. Overall experience, intuitively interpreted and supplemented, is sufficient nevertheless as a basis for a boundary-value treatment of the problem. A mathematical analysis based on a separation of variables, using conventional differential equation methods, provides a useful solution. For a cylindrical ingot, the temperature varies as a Bessel function of an argument proportional to the radius and as an exponential function of longitudinal position. Trial calculations using the problem solution seem to verify the general correctness of the result as compared with experience. The role and nature of solution parameters are also clarified, though not entirely resolved. It is revealed that the barrier to heat flow at the ingot-crucible surface has a prominent influence. Utility of the model embodied in the problem solution is readily demonstrated by considering a variety of contemporary questions about arc melting, and it is hoped that utility can be enhanced by improvement of the model.

Jan 1, 1968

By E. D. Calvert

This Bureau of Mines report discusses the electric-arc reduction of zirconium and hafnium oxides with carbon yielding a metal-metallic carbide mixture. The carbon to oxide ratio in the feed determines the metal to carbide ratio in the product. A sample of this product was produced -or testing as a feed for the deBoer iodide-dissociation process. A new technique for producing pure carbides is described, which uses the intense heat of the arc to volatilize the carbide. The condensed vapor form , crystals of nearly stoichiometric carbide, INTRODUCTION This research examines the preparation of refractory metal carbides in the controlled atmosphere electric-arc furnace.

Jan 1, 1962

By d&apos, Kathleen J. Amico

This summary appears in Minerals Yearbook volumes I-II, and III, which cover mineral production in the United States, its island possessions, the Canal Zone, and the Commonweath of Puerto Rico, as well as the principal minerals imported into and exported from the United States. The sections of this chapter and the area chapters in volume III contain further details on production. A summary table comparing world and U.S. mineral production also is included. Mineral production may be measured at any of several stages of extraction and processing. The stage of measurement used in the chapter is normally what is termed "mine output." It usually refers to minerals in the form in which they are first extracted from the ground, but customarily includes for some minerals the product of auxiliary processing operations at or near mines.

Jan 1, 1967

By d&apos, Kathleen J. Amico

This summary appears in Minerals Year-book volumes I-II, and III, which cover mineral production in the United States, its island possessions, the Canal Zone, and the Commonwealth of Puerto Rico, as well as the principal minerals imported into and exported from the United States. The sections of this chapter and the area chapters in volume III contain further details on production. A summary table comparing world and U.S. mineral production also is included. Mineral production may be measured at any of several stages of extraction and processing. The stage of measurement used in the chapter is normally what is termed "mine output." It usually refers to minerals in the form in which they are first extracted from the ground, but customarily includes for some minerals the product of auxiliary processing operations at or near mines.

Jan 1, 1967

By Kathleen J. D?Amico

This summary appears in Minerals Year- book volumes I-II, and III, which cover mineral production in the United States, its island possessions, the Canal Zone, and the Commonwealth of Puerto Rico, as well as the principal minerals imported into and exported from the United States. The sections of this chapter and the area chapters in volume III contain further details on production. A summary table comparing world and U.S. mineral production also is included. Mineral production may be measured at any of several stages of extraction and processing. The stage of measurement used in the chapter is normally what is termed "mine output." It usually refers to minerals in the form in which they are first extracted from the ground, but customarily includes for some minerals the product of auxiliary processing operations at or near mines.

Jan 1, 1970

By Stephen C. Tadolini, Peter (Yunqing) Zhang

A unique circumstance created by monitoring a pre-driven longwall recovery room permitted measuring the stresses of a coal pillar throughout its entire life cycle in less than a week. A fender pillar, created in approximately the middle of a longwall panel at a depth of 650 ft, transformed from a solid barrier pillar - to a yielding pillar - to a residual pillar as 3 ft slices were methodically removed with the longwall shearer. The complete transformation, or life cycle, took place in less than 12 hours. The stresses were quickly transferred from the pillar onto the standing pumpable concrete supports and into the outby pillars. Roof to floor closure measurements, combined with the timing of the pillar behavior, provides a detailed look at the uncontrollable convergence of underground mine openings. Pillars remain the most important form of “primary support” and understanding these life cycles is vital for safe and efficient mine design, in both room and pillar and longwall panel extractions.

By E. R. Maize

This report is the third of a series on convergence of roof and floor in coal mines and subsidence of surface that accompanies it. The first papery dealt with extraction in a mechanized mine (Montour 10) having relatively short rib lines that retreat rapidly. The second 6/ dealt with extraction in a mine (Crucible) in which coal was loaded by hand and in which the rib lines were long and slow-moving. The present report deals with a mine (Gibson) in which conditions approximated those in the Crucible mine, except that the distance between room centers was considerably less and the pillars were narrower in consequence. Moreover, the average cover was less and the studies were made under the steep hillside of a stream valley compared with a gently rolling surface over the portions of the second mine studied. Gibson mine lies in the east-central part of Washington County, Pa., approximately midway between the Montour 10 and Crucible mines on a north-south line. A cooperative agreement covering the work was made with the Hillman Coal & Coke Co. through W. L. Affelder, vice president. This paper describes the methods used in the investigation, gives excerpts from the data obtained, and offers such generalisations as appear to be justified.

Jan 1, 1940

By Jerry E. Olson

In 1986, at the request of the U.S. Bureau of Land Management, the U.S. Bureau of Mines studied part of the 20,071-acre South Fork Wilderness Study Area (OR-005-033) and part of the 8,791-acre Sand Hollow Wilderness Study Area (OR-005-034) in order to evaluate their identified mineral resources. The study areas are located in Crook County, OR, about 58 air miles east from Bend. The areas studied are underlain by Tertiary- and Quaternary-age volcanic and tuffaceous sedimentary rocks. No mineral resources were identified in or adjacent to the study area. Except for common opal and agate occurrences along the northern boundary of the study areas, no mines, prospects, or mineralized zones occur within the study areas. Bentonite is periodically mined less than 1 mi southwest of the Sand Hollow study area boundary. Neither of the study areas has geothermal leases, but both areas are under lease for oil and gas.

Jan 1, 1987

By E. C. Lane

This paper is the first part of a report giving the results of the Bureau of Mines' twenty-third semiannual survey of motor gasoline marketed in the United States. A companion report, Part II, is in preparation and will give a more detailed discussion of the whole survey. Results of the determination of copper-strip corrosion, color, sulphur content, copper-dish evaporation residue, and gum content as given by the Bureau of Mines steam-oven method will be presented in the second paper, which will also include the prevailing retail price and the tax at the time the sample was taken. This paper deals specifically with data relative to gravity, Reid vapor pressure,5 and distillation (method 100.13).6 The samples tested were divided into "competitive-price gasolines" and "premium-price motor fuels," a method of presentation that was begun with the twenty-second semiannual survey.7 A total of 312 samples were collected from service station pumps in 20 cities throughout the United States. Of this number of samples, 207 were "competitive-price gasolines" and 105 were "premium-price motor fuels." All of the samples were collected in March, 1931, and analyzed at the Petroleum Experiment Station of the United States Bureau of Miner at Bartlesville, Okla.

Jan 1, 1931

By Herbert M. Wilson

The act (36 Stat., 369) that established the Bureau of Mines in the Department of the Interior defined as part of the bureau's province and duty the making of "diligent investigation of the methods of mining, especially in relation to safety of miners and the appliances best adapted to prevent accidents," and it authorized the bureau from time to time to make such public reports of its work and investiga- tions as the Secretary of the Department of the Interior may direct, with the recommendations of the bureau. The national mine-rescue and first-aid conference was projected in the hope that it would be a factor in increasing safety in the mining industry through the recommendation of better and safer methods of conducting mine-rescue operations, more efficient methods of extend- ing and giving training in the use of artificial-breathing apparatus, and approved and more effective methods of administering first aid to injured miners and of training miners in first-aid work. The bureau feels warranted in publishing the resolutions adopted by the conference as a guide to mine workers and others concerned in obtaining greater safety in mining, and in presenting such extracts from the discussion as indicate the reason for the adoption of any particular method. In issuing this bulletin, however, the bureau does not indorse these resolutions in whole or in part as a final ex- pression of its views regarding the best method or procedure in any case. It does believe, however, that the resolutions furnish an excel- lent starting point from which to develop a standard code of pro- cedure in mine-rescue and first-aid work. It will be noted that in some important cases further information is necessary before any standard procedure can be recommended, par- ticularly as regards types of bandages, methods of resuscitation, the use of stimulants, the cumulative effect of poisonous gases, the diet of men engaged in rescue work, the physiologic effect of the pressure

Jan 1, 1913

By Beatrice Lukens, David Schlain, John D. Prater

"The electrolytic manganese process4/ developed by the Bureau of Mines involves the electrolysis of a solution of manganese sulfate and ammonium sulfate in a diaphragm-type cell. Metallic manganese is deposited on the cathodes, and sulfuric acid is produced at the anodes. The spent electrolyte contains, in addition to the sulfuric acid, approximately 40 percent of the manganese sulfate and most of the ammonium sulfate originally present in the feed solution. This spent solution is used to leach fresh ore that has previously been subjected to a reducing roast. The resulting leach liquor is purified and returned to the cell.Manganese of very high purity is produced by the electrolytic process. The properties of this metal are so different from those of the best grade of manganese that can be made by any other commercially feasible process that it is virtually a new material. Electrolytic manganese has been used in the preparation of new high-manganese alloys with valuable properties.3/ and further developments are to be expected. The electrolytic manganese process not only results in a product of superior qualities, but is applicable to large tonnages of domestic ores that are unsuitable for direct use in producing ferromanganese.The future industrial use of electrolytic manganese is of course, related to its cost. Decreases in the cost of production will lead to wider use of the metal; conversely, increases in the volume of production made possible by greater demand will bring further .decreases in cost."

May 1, 1946

By M. J. Kovalik

Lower Sunnyside seam coal from Utah was blended with various proportions of char and high-temperature coke to improve the quality of the coke obtained from carbonizing this coal. The Hanson 5-pound carbonizer was used as a "screening test" for the larger scale Bureau of Mines-American Gas Association (BM-AGA) tests, which were correlated with industrial production. Eighteen carbonization tests were made in the BM-AGA 13-inch retort, with a coal charge of about 90 pounds; the cokes were evaluated by the standard ASTM tumbler test. Carbonization of blends containing char and coke breeze yielded less fissured and blockier cokes of significantly higher ASTM I-inch tumbler indices as compared with the value for the straight Sunnyside coal. It was found that the simultaneous addition of char and coke breeze yielded stronger cokes than that obtained by the addition of either one of these additives. Addition of a small proportion of Pocahontas No. 3 or Sewell coal to an optimum blend improved the resulting coke strength further.

Jan 1, 1969

By R. H. Hiltz

The Coal Mine Health and Safety Act of 1969 legislated maximum dust levels for the working place. As the law was implemented, extensive efforts were undertaken to provide the technology necessary to control dust generation. One approach to dust control was the use of high expansion foam in place of the usual water sprays on coal cutting equipment. At the time of the act, high expansion foam had already seen considerable testing for the suppression of dust in underground coal mines. Work by MSA, several coal companies and the Bureau of Mines itself had provided data which showed foam to have some merit as a dust control mechanism. It suffered in a few areas, however, which limited its practical application. Its principal difficulty was persistence which hampered operations due to foam buildup, but problems were also encountered due to equipment size and form.

Jan 1, 1975

By E. R. Maize

[he scconG rcport of :his st?rI.org 8cdt with o3servatioi:s of conver- gence of roof an4 floor at t!x*re: ?.cc.-.tioris iri til~ ClVucible mine of kke Cru- cib1.o Fuel Co. Data on sl:'ociacnce ?.rd Lztcrcl mwe:~cnt cf the surface were .:lven for two of these areas, a-12 it was mentioned that ~lr~~ilar data were being obtained on a ?art of Pe:sc:rlvtzr.ia Fii~l?trr.y FE:, ~i!lic;l pcser: over the third area. 'I'hie hichw~ :LEO FasseE over t!lc ITenncoli::. :.line of the Bnckeye Coal Co. 9 milcs to ';he so-lth, cnd at P. l~tcr C'..att: ~.nr?r.,cc?r:cntS *.rere mnd.e to make similar observati on3 there. This y: pr mrnmri:.c n Czto obtnino? at those two locetionn,]

Jan 1, 1941

A series of laboratory evaluations examined the impact of water spray pressure, curtain setback distance, and external and underboom spray use for controlling respirable dust levels and sulfur hexafluoride tracer gas concentrations around a continuous mining machine. This mining machine was equipped with a flooded-bed dust scrubber and was positioned in the box or slab cut. Exhaust line brattice was used for all tests. Dust levels were measured in the return airway and at locations representing the operators of the continuous mining machine and the standard and off-standard shuttle cars. Increasing water pressure or using the underboom sprays produced no significant impacts on dust levels, although their interactions did produce some significant impacts. Increasing curtain setback distance often elevated dust levels, likely by reducing the amount of airflow reaching the face. Use of the external sprays created additional airflow around the mining machine that pushed the dust cloud past the scrubber inlets. This significantly increased dust levels at all sampling locations. Tracer gas levels were measured on the off-curtain and curtain sides of the cutter head and in the return airway. Increasing water pressure generally led to significantly increased gas levels on the curtain side, although a slight decrease was observed on the off-curtain side with the machine in the box cut. Increasing setback distance elevated gas levels on both sides of the cutter head and in the return by limiting the quantity of ventilation airflow reaching the face. Use of the external sprays provided additional airflow along the off-curtain side of the machine, significantly reducing gas levels in this region. These sprays adversely impacted the dilution and removal of gas on the curtain side of the cutter head. Use of the underboom sprays adversely impacted gas levels on both sides of the cutter head. Use of the external sprays provided the best control of respirable dust and face gas concentrations. The smaller increases in miner operator dust levels produced by these sprays were offset by larger reductions in face gas levels on the off-curtain side of the cutter head. Although the underboom sprays minimally impacted respirable dust levels, use of these sprays was not recommended because they increased face gas levels.

Jan 1, 2007

By R. T. C. Rasmussen

"INTRODUCTION The primary purpose of the Bureau of Mines electrolytic manganese pilot plant at Boulder City, Nev., is to improve the Bureau-invented electrowinning process and to determine the applicability of the process to the extensive domestic low-grade manganese ores with a view to making the United States dependent upon foreign sources of manganese. 3/4/ Incidental to accomplishing this purpose, the pilot plant has produced a substantive quantity of electrorytic manganese since the start of operations late in 1941; present cabacity about 1 ton a day of manganese metal. A second important purpose of the pilot plant is the supplying of electrolytic manganese for full-scale tests in cooperation with industrial users of manganese.The Rustless Iron& Steel Corp., Baltimore, Md., was the first steel company to cooperate with the Bureau of Mines in large-scale testing of electrolytic manganese. Arrangements were made with C. E. Tuttle, then president of the corporation, whereby the Bureau would supply electrolytic manganese to make a sufficient number of full-scale stainless-steel heats to demonstrate thoroughly its merits as a replacement for low-carbon ferro-manganese in the corporation's stainless-steel practice. The corporation's purpose in the investigation was to determine the possible advantages of electrolytic manganese resulting from its almost complete lack of phosphorus and caroon that might offset its then considerably higher cost per unit of manganese than low-carbon ferromanganese. The data presented herein are based upon reports of A. L. Field, technical director, and L. Weitzenkern, research engineer of Rustless Iron & Steel Corp.; they are supplemented by observation of the author who visited the plant during the tests."

Oct 1, 1945