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By S. S. Dean, B. Silkes

"INTRODUCTION The metallurgical-research program of the Bureau of Mines .for the past 15 years has emphasized the production of high-purity nonferreus metals through the utilization of our available resources, ores, reducing agents, fuel, and power.Ore dressing or concentration, has always been a vitally important part of nonferrous metallurgy, and the Bureau continues to give most of its attention to it. In the field of the traditional nonferrous metals, the Bureau staff has developed natural-gas reduction of zinc, the application of glomerule technique to preparing high-grade lead concentrates for Scotch-hearth smelting, the production of electrolytic antimony from precious metal-bearing ores, and the recovery of nickel from nickel-chrome-iron ores.In the field of light metals, the Bureau staff has developed several improvements in both magnesium and aluminum production and in alloys of these metals. In the so-called ""rare-metal"" field, Bureau activities have included the production of pure ductile titanium on a larger scale than heretofore attempted, the electrolytic production of cobalt, chromium, and manganese which may now take their proper places as bases for nonferrous alloys as well -as ingredients of special steels. The Bureau staff has investigated many of these new alloys. Investigations of methods of recovering vanadium from its low-grade domestic ores have given promising results. Methods for the preparation of metallic zirconium have been improved."

May 1, 1947

By John B. Gayle

The Bureau of Mines has designed and constructed an experimental coke oven, using a commercial oven as a model where practicable. Because the rate of carbonization is important in determining the quality of the coke produced and may affect the "mount of pressure developed during carbonization, particular attention was given to those elements of the design that govern the heat transfer to the charge. The new oven deviates in design from most existing test ovens in that the charge is full width (17 inches), the heating walls ore constructed of 4-1/2-inch silica brick, and zoned, heat-input arrangements compensate for heat losses at the ends, top, and bottom of the charge. This report describes the oven, which was designed by H. S. Auvil and installed under his direction, at the Southern Experiment Station, Tuscaloosa, Ala., while he was supervising, engineer, Coke Section. It gives the results of a limited number of carbonizing tests. These results indicate that the main objective in designing and building this oven, that off duplicating commerical, slot-oven carbonizing conditions, has been accomplished; if coke-discharge conditions simulate commercial-oven conditions, the cokes from the experimental oven arc very similar to oven coke, in soma tests being fully as close is duplicate tests from a Angle batch of coke.

Jan 1, 1952

By D. J. Parker, J. B. Benson, J. H. Bird, F. E. Cash

"INTRODUCTION The organic act that became effective July 1, 1910, imposes two very definite primary obligations upon the Bureau of Mines: (1) The prevention of loss of life and limb and the protection of the health of workers in the mineral industries, and (2) the conservation and scientific utilization of the country's mineral resources.The subject of this publication falls within the scope of both of these responsibilities by reason of the fact that (1) certain safety precautions are involved in combating even surface fires and, (2) although peat is not now, so far as known, utilized commercially or otherwise in this country as a fuel, it is extremely valuable agriculturally in at least one of our States, The justification for the conservation of such low-grade fuel through fire prevention appears warranted because of its present value to agriculture and the possible advantages accruing to future generations as a source of heat and power.Although the Bureau of Mines has published information on the origin and uses of peat, this is the first attempt to give out data concerning the prevention and control of peat-bog fires. Although the information presented here is restricted to the Lake Superior District, California, and Florida, there may be similar conditions in other sections of the country that have not come to the attention of engineers of the Bureau of Nines."

Jul 1, 1947

By Sean Gallagher

The restricted workspace present in low-seam coal mines forces workers to adopt awkward working postures (kneeling and stooping), which place high physical demands on the knee and lower back. Method: This article provides an analysis of injury claims for eight mining companies operating low-seam coal mines during calendar years 1996-2008. All cost data were normalized using data on the cost of medical care (MPI) as provided by the U.S. Bureau of Labor Statistics. Results: Results of the analysis indicate that the knee was the body part that led in terms of claim cost ($4.2 million), followed by injuries to the lower back ($2.7 million). While the average cost per injury for these body parts was $13,100 and $14,400, respectively (close to the average cost of an injury overall), the high frequency of these injuries resulted in their pre¬eminence in terms of cost. Analysis of data from individual mining companies suggest that knee and lower back injuries were a consistent problem across companies, as these injuries were each among the top five most costly part of body for seven out of eight companies studied. Application/Impact: Results of this investigation suggest that efforts to reduce the frequency of knee and low back injuries in low-seam mines have the potential to create substantial cost savings.

Jan 1, 2009

By James F. Neill, O&apos

Brown iron ore resources in Barbour, Butler, Crenshaw, and Pike Counties were investigated in a drilling program and geological study by the Federal Bureau of Mines in cooperation with the Alabama Geological Survey and the University of Alabama. The aggregate footage drilled was 18,010 linear feet. When developed, reserves of 12,664,000 long tons of crude ore were indicated, containing from 26.9 to 29.0 percent iron and 0.2 to 1.6 percent manganese under a maximum overburden of 40 feet. Total inferred crude ore for the four counties was calculated to be 827,700,000 long tons. Beneficiation of samples by simulated log washing and use of a 1/8-inch screen yielded from 46.8 to 51.7 percent iron and 0.2 to 2.6 percent manganese. Screen-test studies indicated no appreciable interlocking between the iron and manganese minerals and the waste particles of materials retained on a 200-mesh screen. Clay was prominent in micron-size slimes. Silica was deleterious in the minus 20-mesh size. While an indicated 2,198,000 dry long tons of usable iron ore can be recovered, sink-and-float tests show that it may be possible for 4,654,000 dry long tons to be recovered by other than log washing. However, applicable commercial processes have not been demonstrated.

Jan 1, 1965

By James F. Neill, O&apos

Brown iron ore resources in Barbour, Butler, Crenshaw, and Pike Counties were investigated in a drilling program and geological study by the Federal Bureau of Mines in cooperation with the Alabama Geological Survey and the University of Alabama. The aggregate footage drilled was 18,010 linear feet. When developed, reserves of 12,664,000 long tons of crude ore were indicated, containing from 26.9 to 29.0 percent iron and 0.2 to 1.6 percent manganese under a maximum overburden of 40 feet. Total inferred crude ore for the four counties was calculated to be 827,700,000 long tons. Beneficiation of samples by simulated log washing and use of a 118-inch screen yielded from 46.8 to 51.7 percent iron and 0.2 to 2.6 percent manganese. Screen-test studies indicated no appreciable interlocking between the iron and manganese minerals and the waste particles of materials retained on a 200-mesh screen. Clay was prominent in micron-size slimes. Silica was deleterious in the minus 20-mesh size. While an indicated 2,198,000 dry long tons of usable iron ore can be recovered, sink-and-float tests show that it may be possible for 4,654,000 dry long tons to be recovered by other than log washing. However, applicable commercial processes have not been demonstrated.

Jan 1, 1965

By William W. Elmer

This paper, describing the mining method at the Black Butte quicksilver mine, is one of a series of papers being prepared by the U. S. Bureau of Mines on mining practices, methods, and costs in the various districts of the United States. It is presented to show the mining practice and costs in the successful treatment of low-grade quicksilver deposits. The operation discussed is an excellent example of w1-pat can be done in working a limited tonnage of low-grade ore under sound management. The Black Butte mine is situated at Black Butte, Lane County, in the southern part of the State of Oregon, 17-1/2 miles from Cottage Grove -- a station on the Siskiyou branch of the Southern Pacific Co. The Black Butte mining district lies in the foothills of the Calapooia Mountain Range, which connects with the Cascade Range on the east and with the Coast Range on the west. The elevation at '.lie reduction plant is 1,000 feet above sea level. The apex of Black Butte Mountain, or which the mine is situated, has an elevation of 2,700 feet. The district possesses exceptional natural facilities infrequently met with elsewhere for the mining and reduction of cinnabar ores. Several factors which contribute to the unusually low mining costs are:

Jan 1, 1930

By E. C. Tarpley, H. M. Cooper, R. F. Abernethy

"INTRODUCTION The float-and-sink test 5/6/ is generally the first test used in determining the washing characteristics of coal. The simplest form of the test is that of using one solution of such specific gravity that the test sample is separated into ""float"" and ""sink"" fractions. In practice, however, a series of solutions is used, and the sample is separated into a number of fractions of a definite specific-gravity range. Analyses of a series of fractions of this type are often referred to as the ""specific-gravity analysis,"" and are of great value in the selection, construction, and operation of commercial washing equipment.The test is rather simple to use, provided a number of conditions are recognized and as many as possible held constant, such as:1. In laboratory testing, two types of solution are available -Aqueous solutions of calcium and zinc chlorides.Mixtures of organic liquids such as carbon tetrachloride, benzene, gasoline, bromoform, etc.2. Absorption of the solution by the coal,3. Solvent action of the solution toward the coal.4. Constancy of specific gravity during the test is affected by temperature changes, dilution, and evaporation.5. Personal technique of the test, such as the time the coal is in the liquid, rate of adding the sample to the liquid, stirring, time of draining, etc.6. Moisture content of the coal as tested."

Dec 1, 1947

By E. D. Gardner

About 300 tons of gold ore per week was being produced in February 1934 by Thomas D, Herron and Con Laster from the old lake Superior and Arizona workings; the ground was leased from the Magma Copper Co. The workings adjoined but were not a part of the Magma mine. The lessees had been employees of the Magma Copper Co, at the time the Magma closed down for the summer of 1932. Work on the lease began in July 1932 on an exposure of $2-per-ton ore disclosed in a drift; after a few hand-drilled rounds were blasted the gold content increased to about $30 per ton. Extensive sampling by pannings elsewhere of exposed portions of the vein indicated that other ore shoots existed. The last work previously done in the mine was during the World War, when lessees mined a number of small shoots of copper ore. In some of the stapes the copper miners had left a quartzose streak on the hanging wall that carried $15 per ton of gold. This material did not look as if it cried values and evidently never had been sampled. The first shipment of gold ore was made on September 28, 1932. Up to April 1, 1933, 3,778 tons had been shipped and from September 1, 1933, to January 31, 1934, 3,125 tons.

Jan 1, 1934

By R. G. Meara, O&apos

[P.F? bmit e-ninirq ir.3.l r;tq: in the Znited State :; was u~irlyortant p~ior to the Torld ;Jar, ?-.lt with the c~r,sxti~rl of imports d11rln.c thr World 'Jar tke Rmericnn mar~factu~er:. of 1itkopone mcl Sayiun c;~oai?als forced tile tl~veloor?.ent of domertic bar,i$e dqosit9. Pr%~~,n-ily bcca-lse of tho increasing dc.n;;nl'i for lit,hupone3 by the pr?i:~t, Tlocr-covcrin~;, ,md rt1tbe.r indl~stries, ~3c.vs1o~:rnc2t of cto~entic de~onits has cr~ntim~ed to c-cpand. 13 1914, the salnr! oC doxegtic c~l~.dt? t,m-it~ ;u~cr-~nteii. to 52,91? tons, in 1237 ???,1!.1 tons nmre so1.d; thc 12:t~r rcyrprcntcd 77 .E;T pmccnt of the tot,:rl, dr??;ectic and imortcd., haritd US~C in the Cnited State? di7rinz t,hat :.vXr. C,f +he total 193,3:& ton? coy.1~-ed in the United 4 Steter ir. 135, 3E.X percent v;as usec? as groi.z.ld ~rai.te? , "0.3 percent arr lithopone, and 17 .:A ].ercc?t in the rnx 11fact,ure of b;~riim chs:nicals ]

Jan 1, 1938

By R. G. Meara, O&apos

[P.F? bmit e-ninirq ir.3.l r;tq: in the Znited State :; was u~irlyortant p~ior to the Torld ;Jar, ?-.lt with the c~r,sxti~rl of imports d11rln.c thr World 'Jar tke Rmericnn mar~factu~er:. of 1itkopone mcl Sayiun c;~oai?als forced tile tl~veloor?.ent of domertic bar,i$e dqosit9. Pr%~~,n-ily bcca-lse of tho increasing dc.n;;nl'i for lit,hupone3 by the pr?i:~t, Tlocr-covcrin~;, ,md rt1tbe.r indl~stries, ~3c.vs1o~:rnc2t of cto~entic de~onits has cr~ntim~ed to c-cpand. 13 1914, the salnr! oC doxegtic c~l~.dt? t,m-it~ ;u~cr-~nteii. to 52,91? tons, in 1237 ???,1!.1 tons nmre so1.d; thc 12:t~r rcyrprcntcd 77 .E;T pmccnt of the tot,:rl, dr??;ectic and imortcd., haritd US~C in the Cnited State? di7rinz t,hat :.vXr. C,f +he total 193,3:& ton? coy.1~-ed in the United 4 Steter ir. 135, 3E.X percent v;as usec? as groi.z.ld ~rai.te? , "0.3 percent arr lithopone, and 17 .:A ].ercc?t in the rnx 11fact,ure of b;~riim chs:nicals . ]

Jan 1, 1938

"There seems to be some confusion between the terms carbon black and lamp black, although in American lampblack is generally understood to be a soot formed by the smudge process. In this process oil, coal tar, resin or some solid, or carbonaceous substance is burned in an insufficient quantity of air, while on the other hand carbon black is a product resulting from the incomplete combustion of gas and is deposited by actual contact of flame upon a metallic surface.The various carbons, such as gas retort coke, oil retort coke, graphite, carbon black, lampblack, vine black, wood-pulp,black, willow charcoal, and blacks made from refuse material such as leather have different characteristics as to flocculence strength of color, and physical structure. These blacks are made by one of the following methods:(1) Formation by direct contact of a flame upon a depositing surface.(2) Production by combustion of an oil, tar, etc., in an inadequate supply of air; the soot is allowed to slowly settle out on the floors and the walls of the collecting chambers.(3) Carbonization of solids and subsequent reduction to a state of small subdivision.(4) Production by heating carbonaceous vapors or gases to a decomposition temperature by external heating with or without air in the forming chamber. This is usually referred to as cracking or thermal decomposition."

Mar 1, 1920

By Mark S. Sanders

The purpose of this work was to develop and field test improved knee protection for underground coal miners working in low seam mines. In a previous phase of this contract (Sanders, 1982), experimental knee pads were developed and field tested. The field test revealed several design deficiencies with the knee pads, and suggestions for improving the design were made. The work summarized in this report, therefore, consists of modifying the design and method of fabrication of the knee pads originally describes by Sanders (1982), and of field testing the improved design. The new prototype was shorter and wider than the original design, and used a neoprene pass-through strap design rather than a cloth strap molded into the pad itself. The new prototype was constructed by slush molding a hollow bladder that was then filled with foam. Initial reactions to the pads in the field test were very positive. However, after two months, the opinions about the new prototype became less positive. They were judged, generally, to be no better or worse than the pads usually worn by the field-test participants. Problems were encountered in the field with respect to durability. Water seeped into the inner cavity of many of the pads and caused the foam to deteriorate. It was concluded that it would not be cost-effective or feasible to significantly improve upon current commercially available knee pad designs.

Jan 1, 1986

[~lis is the f'fth in a ~erieG of reports on properties of commercial motor fuels, made in accordance 1,'Vi t:h fl cooperative ae,ree-ment betwGon tho Cooperative Fuel ReRRarch (e.F.R.) Committee and the Bureau of I ines of the Dcpart~ent nf the Interior. The first report gave data on motor r-asolino~ sold during the wintor of 935-36.31 Thi~ report covers 84 brands of ga~oline represented by l,722 samples exclurling the Pacific Coast. T 3)Se J.rom th~. ?~'tcific Coast IV .ro avnrL)f:od b~r tho Pacific Coa!3t tecilnical group "bofore o8ing submi ttcd ruld arc p~.lbl:'shcd GX Gtl~r as they were submi tted. In some areas r~lJort~ . erc roceivod f~om ~ ix to eicht compD.l1ie~ on the same brands of gasoline. whoruar. in other areas only one company reported on a brond. Thut., it CU .. "! be senn that BO .. 0 uf the dnt ;.U'e more rCY>l'c entat vc thM others. The inclusion of r~0rts fro:n several ci tie. w' thin somo of tho di stricts has ir.rpr,)vcd the report by reducinc; tr.e numb~r of brand rcportel by only ono company. ]

Jan 1, 1938

[~lis is the f'fth in a ~erieG of reports on properties of commercial motor fuels, made in accordance 1,'Vi t:h fl cooperative ae,ree-ment betwGon tho Cooperative Fuel ReRRarch (e.F.R.) Committee and the Bureau of I ines of the Dcpart~ent nf the Interior. The first report gave data on motor r-asolino~ sold during the wintor of 935-36.31 Thi~ report covers 84 brands of ga~oline represented by l,722 samples exclurling the Pacific Coast. T 3)Se J.rom th~. ?~'tcific Coast IV .ro avnrL)f:od b~r tho Pacific Coa!3t tecilnical group "bofore o8ing submi ttcd ruld arc p~.lbl:'shcd GX Gtl~r as they were submi tted. In some areas r~lJort~ . erc roceivod f~om ~ ix to eicht compD.l1ie~ on the same brands of gasoline. whoruar. in other areas only one company reported on a brond. Thut., it CU .. "! be senn that BO .. 0 uf the dnt ;.U'e more rCY>l'c entat vc thM others. The inclusion of r~0rts fro:n several ci tie. w' thin somo of tho di stricts has ir.rpr,)vcd the report by reducinc; tr.e numb~r of brand rcportel by only ono company.]

Jan 1, 1938

By John A. Davis, John Gross

This paper is one of a series giving the results of metallurgical tests conducted by: the Alaska station of the Federal Bureau of Iſines, on the recovery of gold from the black sands of placer clean-ups. The data given in this report were obtained from tests on a lot of black sand from a property located on St. Patrick Creek, Fairbanks mining district, Territory of Alaska. This property comprises the Sagan Fraction and adjoining bench claims, and is being operated by J. A. Lillie. The sand ad already been treated at the mine by amalgamation. A sample taken by Mr. Lillie and assayed at the station showed that the gold still remain ing amounted to ll cents per pound. As this gold content was sufficiently high to justify further treatment of the same, 770 pounds were shipped to the station for testing. The reader will note that the gold content is given in cents per pouni, rather than per ton. This is in conformity with practice in the district in valuing black sands, as the quantity obtained at any one time is small, much less than one ton. . The sand consisted principally of schist and quartz, with very little ilmenite and garnet; and no magnetite or sulphides. Most of the gold present as contaminated with quartz, as the free particles of gold had been removed by amalgamation at the mine.

Sep 1, 1920

By E. V. Cilento, K. A. DiGregorio, R. C. Lantz

Pulmonary inflammation is accompanied by increased microvascular permeability and leakage of plasma into alveolar spaces. Serum has been shown to affect superoxide (O2-) production from pulmonary alveolar macrophages (PAM) in vitro, and in some cases serum has been shown to be necessary for stimulation of PAM. An electro-optical method was used to measure O2- production from single PAM by measuring the reduction of nitroblue tetrazolium (NBT) to a diformazan precipitate (NBTH2) from videorecorded images of individual cells. PAM were stimulated by their initial attachment to culture dishes independent of serum. The addition of 2% serum to the culture medium increased NBTH2 production during attachment, whereas concentrations of 5 and 10% serum had no additional effect. In contrast, PAM incubated for 2 hrs could not be stimulated by phorbol myristate acetate (PMA) or zymosan particles to produce O2- unless serum was present during the incubation and/or stimulation; however, NBTH production was similar in all cases of serum addition. Also2, serum alone did not stimulate adherent PAM indicating that serum is necessary but not sufficient for stimulation of attached. PAM. These results suggest that changes in microcirculatory permeability may have a pronounced effect on superoxide production by PAM and that serum may help regulate or condition these cells during inflammation of the lung. (Supported by USBOM Gll35142.)

Jan 1, 1988

The panic bars (and associated linkages and electrical circuitry) that are defined in this document are a machine operator-actuated control for the emergency deenergization of the tram motors on self-propelled, electric and diesel face equipment; including haulage equipment such as shuttle cars. There are nine basic types of panic bars (and several variations) that are recommended in this document, but all of the panic bars are characteristically of the "fire door" type that is frequently encountered on outside exit doors of many public and some commercial buildings. It is also the intent of the following panic bar designs that, when emergency brakes are added to the face equipment machinery for which they arc required, that they be designed and hooked up so that actuation of the panic bar will result in automatic application of the emergency brakes (immediately following the deenergization of the tram motors). The following panic bar design requirements are a restatement of the proposed requirements defined in the Federal Register, requirements cited in "Guidelines for the Design and Installation of Devices for Deenergization of Self-Propelled Electric Face Equipment/Automatic Emergency Brakes" by G. E . Lester and J. D. Greenhalgh of MESA, and Bendix recommendations that were formulated as a result of discussions with personnel at the various machine manufacturers and underground coal mines that we surveyed, discussions with G. L. Judy (our consultant), etc:

Jan 1, 1974

By H. Reginald Hardy

This report is Volume II of a three volume final report dealing with the microseismic monitoring of a longwall coal mine. The research presented in Volume II is concerned with the evaluation of field techniques for obtaining seismic velocity data required for computing microseismic source locations. The report describes the evaluation of a number of different field techniques and the seismic velocity data obtained at the Greenwich mine site where the micro-seismic studies, described in Volume I of the final report, were carried out. Three different methods were employed to evaluate seismic velocities, namely; surface refraction, down-hole, and transmission. In all cases the seismic sources were either located on surface (mechanical impact) or near-surface (explosive charges). It was found that a mechanical energy source could be conveniently utilized to determine shallow velocities and make bedrock-regolith interface depth determinations. For deeper velocity determinations suitable explosive charge sources Here required. In general, refraction data did not always plot in a linear manner and some subjective interpretation was necessary. The down-hole method was found to be useful for incremental vertical velocity evaluation, however, the transmission method provided the most consistent average vertical velocity data. At the Greenwich site seismic velocities were found to be anisotropic with values ranging from 9,551 to 10,739 feet per second depending on direction.

Jan 1, 1977

By Richard A. Thomas, Michael J. Sapko, Gary L. Mowrey, William D. Monaghan, Michael A. Trevits

Over the years, more than 20,000 mine seals have been erected in underground coal mines in the United States. Seals are used extensively in underground mines to isolate worked-out areas, active mine fire zones, and to control water inundations. Seals are most often built directly in the mine and can be fabricated from blocks made of wood or cementitious material. Recently, several explosions occurred within sealed areas of underground U.S. coal mines. These explosions, believed to be initiated by lightning strikes on the surface, destroyed numerous seals and caused considerable damage external to the sealed area. The National Institute for Occupational Safety and Health is conducting research to develop design guidelines, to investigate noninvasive techniques to characterize seal strength properties, and to evaluate seal test methods. As part of this work, a 30-ft wide, 16.1-ft tall and 4-ft thick seal was built in an underground experimental mine using cement and foamed water. Two types of noninvasive techniques are currently being investigated, namely the Schmidt Hammer for measuring compressive strength and ground penetrating radar (GPR) for detecting the presence of anomalies (e.g., voids, discontinuities) within the seal. Once these noninvasive tests were completed, the seal was subjected to destructive explosion testing. This study presents the results of the Schmidt Hammer tests, GPR scans, and the characteristics of seal failure during explosion testing.