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By D. Bienstock, J. H. Field, M. J. Lempel

A computer program is presented to perform the detailed and numerous calculations required for determining the interface temperatures and steady - state heat flow through a furnace wall composed of several refractories in layers . A method is developed that will allow the designer to determine the various thicknesses for each refractory layer to minimize either the total wall thickness or the cost of the wall per unit of area . A sample problem is presented and analyzed to illustrate the techniques involved .

Jan 1, 1964

By James Westfield

Uranium activity has introduced a comparatively new hazard to United States mining. In addition to the hazards common to all mines, uranium mines have a complex health problem of radiation damage. Like many new processes, radiation and nuclear energy can be made to serve man in many useful ways when properly understood and handled; but, like fire, gases, and electricity, their potential dangers must be known and respected, and appropriate precautions must be taken or death may result. Since 1950 the Public Health Service has been conducting basic investigations on exposure to radon and its daughter products and the effect of exposure upon the health of miners in uranium mines of the Western States. The Bureau of Mines assisted in several of these investigations, especially in mines on Indian lands. The studies have shown that a serious health hazard exists from radioactive exposure that might cause lung cancer if continued over a number of years. The Public Health Service report, Control of Radon and Daughters in Uranium Mines and Calculations on Biologic Effects,6/ shows that 55 percent of the uranium mines employing 64 percent of the miners had atmospheric concentrations more than five times the working level now accepted as reasonably safe for industrial exposures. Extensive control measures are necessary to reduce these concentrations to the suggested working level of less than 300 micromicrocuries of total radon daughter products per liter of air.

Jan 1, 1958

By C. J. Thompson

This Bureau of Mines study describes the preparation of sulfur compound concentrates boiling from 225° to 400° C, and reports the sulfur types detected in these concentrates by low-voltage mass spectrometry (LVMS). Existing LVMS methods were extended; the procedures described should be generally applicable to high-boiling petroleum distillates and concentrates as a preliminary means of narrowing the number of factions to be considered for more detailed separation and identification studies. The following major sulfur compound constituents of petroleum are indicated by the data: benzothiophenes, dibenzothiophenes, naphthanothiophenes, naphthenobenzothiophenes, and homologs and isomers of these. Cyclic and chain sulfides comprise a significant portion of the gas-oil range sulfur compound types. The presence of some classes of sulfur compounds containing two sulfur atoms per molecule was indicated.

Jan 1, 1966

By L. B. Berger

"INTRODUCTION Accurate determination of carbon monoxide in concentrations ranging from 0.2 to about 0.5 percent by volume is troublesome, because such concentrations are too high for some analytical methods and too low for others. Methods that are sensitive to concentrations of carbon monoxide considerably less than 0.2 percent are approaching their upper limit of usefulness when applied to the analysis of samples containing 0.2 percent or more of carbon monoxide, and it may be necessary to resort to dilution of the sample with a known proportion of air, or otherwise modifying the analytical technique, to obtain satisfactory results. Such methods include the determination of carbon monoxide by reduction of heated iodine pentoxide 3/4/5/ by the ""Pyrotannic acid"" method 6/ and by the so-called ""phosphomolybdic acid"" method. 7/ The use of conventional gas-analysis equipment, such as the Orsat type, in the determination of carbon monoxide in concentrations ranging from 0.2 to 0.5 percent is not desirable, as possible analytical errors may be of about the same magnitude, thus producing results of little quantitative value.For several years prior to this publication, the Gas Analysis Laboratory of the Health Division of the Bureau of Mines has used a modification of the Haldane type 8/9/10/ gas-analysis apparatus for the determination, by absorption in a chemical reagent, of carbon monoxide in low concentrations that are not readily determined by other methods. The method is applicable also to the determination of higher concentrations. As the procedure has proved successful and has been adopted by others, this report was prepared to describe the method and to present results of analyses obtained with it."

Nov 1, 1947

By D. J. Stoops, H. Kato, M. D. Carver

The effects of impurity elements silicon , aluminum, copper , nitrogen , and manganese , at 50 to 300 ppm, on properties of the zirconium alloy Zircaloy 2 were investigated . Variations in microstructure , mechanical properties , and corrosion behavior in some inorganic acid and salt solutions were observed with variations in level of impurity element . Corrodents were solutions of sulfuric acid , phosphoric acid , copper chloride , and iron chloride . Silicon was found to modify annealed microstructures by spheroidizing and dispersion of secondphase material throughout grains . Silicon or manganese improved ultimate and yield strength of the alloy without loss in ductility . All five elements affected corrosion rates of the alloy , the effect being generally different for each element .

Jan 1, 1964

By G. W. Birge, D. E. Wolfson, J. G. Walters

Seventeen samples were carbonized by the BM -AGA pilot - plant test method and in industrial ovens . Chemical and physical properties of the samples were determined , and the physical properties of the cokes prepared by the two methods were compared . Since the capacity of the plants from which these samples were obtained is about 30 percent of the 1959 total for the United States , the data given in this report are indicative of the chemical and physical properties of blends used to produce industrial cokes and the acceptable chemical and physical properties of the resultant coke .

Jan 1, 1964

By C. A. Herbert

Information Circular 6746 reviewed the fatalities in Indiana coal mines. for the fiscal year October 1, 1951 to September 30, 1933. Since then Indiana has changed its fiscal year to the period July 1 to June 30, but as most statistical data on accidents are arranged according to calendar years, the data in this paper are for the last 3 months of 1932 and the calendar year 1933, rather than for the new Indiana fiscal year. Tables 1 and 2 list the fatalities in Indiana coal mines3/ by cause and occupation for the last 3 months of 1932 and for the calendar year 1933. The fatalities for the small wagon mines employing fewer than 10 men are separated from those employing 10 or more men to call attention to the ex- tremely high fatality rate in small mines, largely because the State mining law does not apply to them nor do they come under the jurisdiction of the Indiana mine inspectors; as a result health and safety conditions are ex- tremely bad. During the last 3 months of 1932, 5 (approximately 42 percent of the total) fatalities occurred in the small mines, while for the calendar year 1933, 12 (approximately 32 percent) of the fatalities occurred in them. The Indiana Division of Mines and Kining estimates that these small mines have an annual production of approximately 325,000 tons, or about 4.5 percent of the total coal-mine production of the State. In other words, for these small mines the fatality rate per tons mined during 1933 was about 10 times as great as for the mines employing 10 or more men. Another lamentable feature in connection with the fatalities in small mines is that very few carry any compensation insurance and the owners are not worth enough financially for dependents of victims to collect anything under the common law; as a result, the dependents of those killed usually are left penniless and subjects of public charity.

Feb 1, 1935

By Jack E. Tress

The Bureau of Mines has been involved for several years in the development of processes for the recycling of solid wastes. As part of this program, a project was initiated to determine the feasibility of producing secondary pig iron from auto scrap. During the test period, 86,000 pounds of shredded auto scrap, along with petroleum coke and fluxing agents, was charged to a submerged-arc furnace of 1-ton nominal capacity. Eighty-eight thousand pounds of pig iron, with an average carbon content of 3.90 percent and an average copper content of 0.2 percent, was produced at an electrical consumption of 512 kW-hr per net ton. A cost estimate of the process showed that the pig, iron might be produced at a cost of $57 per ton.

Jan 1, 1973

By Maria I. De Rosa

Table 10 and figure 4 show the number of fires and fire injuries occurring at the surface of underground metal/nonmetal and stone mines by state during 1990-2001. Table 10 also shows the injury risk rates, employees' working hours, and lost workdays. A total of 12 fires occurred in 11 states; 5 of the fires caused 5 injuries. The yearly average was one fire and 0.42 injury. Five fires with two injuries occurred at metal mines, five fires with two injuries occurred at nonmetal mines, and two fires with one injury occurred at stone mines. None of the fires involved contractors. The Ewhr value was 58 x 106 hr (Irr = 0.017), and the LWD value was 75. Nevada had the most fires (two fires and no injuries). Ohio, New Mexico, Missouri, South Dakota, and Idaho each had one fire with one injury. Of these states, Missouri had the highest injury risk rate value (In = 0.25). Table 11, partly illustrated in figure 5, shows the number of fires, fire injuries, risk rates, employees' working hours, and lost workdays by time period. The number of fires decreased during most of the six time periods. The number of fire injuries and employees' working hours decreased during all of the periods. The Irr values follow patterns similar to those shown by the injury values. Tables 12-17 show the number of fires by ignition source, method of detection and suppression, equipment involved, location, and burning material by time period. Figure 6 shows the major variables related to fires for 1990-2001. Table 18 shows the number of fire injuries per number of fires causing injuries and total fires by year, ignition source, equipment involved, and location.

Jan 1, 2004

By K. K. Kershner, J. G. Donaldson

This investigation was conducted to obtain data on optimum conditions for chloridizing metal sulfides . Salt- roasting galena at 450° C for 8 hours chloridized 75 percent of the lead ; in an equal time of treatment at 750° C , the process chloridized 42 percent of the zinc in sphalerite . Hydrogen chloride at 500° C completely chloridized galena in 15 minutes , and at 600° C converted all of the zinc in sphalerite to the chloride in 4 hours .

Jan 1, 1963

By Victor E. Kral

The Modarelli iron deposit , formerly known as the Requa iron deposit , is 44 miles by road south of Palisade , Nev . , on the Southern Pacific and Western Pacific Railroads . Construction of 10 miles of new road, which is necessary in case the property is exploited , will reduce this distance to about 28 miles . The deposit was discovered in 1905 , and patent was obtained in 1907 . The present owners obtained title to the property in recent years by paying the delinquent taxes . There has been no production . The ore deposit is a replacement of a Tertiary volcanic believed to be a rhyolite . Except for evidence of slight shearing , the deposit has no apparent structure . Hematite is the principal ore mineral ; it is fine-grained and is associated with very fine-grained apatite and unidentified minerals assumed to be alteration products of residual rhyolite minerals .

Feb 1, 1947

By K. E. Tame

The Bureau of Mines is studying possible modifications in conventional uranium ore-processing steps to confine and permit controlled disposal of radioactive wastes. Surveys of Ra226 contamination of liquid wastes from uranium mills indicated that the Vanadium Corporation of America plant at Durango, Colo., had one of the more urgent problems. A possible procedure for minimizing the waste disposal problem was to reuse the waste solution in the mill--in effect, erasing the need for disposal of liquid waste. In examining this possibility, interlocked bench-scale leaching and solvent extraction tests simulating the Durango flowsheet were made. The simulated reuse of barren raffinate for leaching and washing was carried through three separate campaigns of 9, 12, and 35 cycles each.

Jan 1, 1961

By Hillary W. Clair

An equation is derived for the rate of reaction of a sphere of metal oxide in a restricted enclosure through which a reducing gas is flowing . The equation takes into consideration the reaction rate coefficient , transport through the gas and through the porous shell of reduced oxide , the rate of gas flow , and the volume of the enclosure . The equation serves as a model for predicting the course of reduction of a particle of metal oxide in a shaft furnace .

Jan 1, 1964

By R. M. Gammell, S. H. Lorain

The Anderson prospect is one of a number of properties investigated by the Bureau of Mines during the course of preliminary studies of the lead-zinc districts of northern Stevens County, Washington. examined by W. R. Green, an engineer of the Bureau of Mines, in June 1944. This examination was supplemented in late 1944 and the spring of 1945 by pre- The property was first liminary angle-dozer trenching and core-drilling. A second examination of the property was made by the junior author in November 1945. The data obtained in the course of these studies is presented in the following report.

Mar 1, 1947

By Thomas J. Albin

This U.S. Bureau of Mines report identifies potential causes of slip-and-fall accidents occurring during surface mine equipment maintenance and describes the relative roles of direct worker behavior and machine design. The relative roles of human behavior and machine design in the causation of slip-and-fall accidents were determined through analysis of accident records, observations of maintenance worker behavior, and evaluation of mine machinery. From these data, relative risk ratios were calculated. Behavior had a relative risk ratio of 1.5; machine design, specifically access systems design, had a relative risk ratio of 2.2. Of the access systems, ladders had the highest relative risk ratio, 7.0. This study suggests that accident intervention would be most profitably made in improving the design of systems used to access maintenance worker areas of mining equipment.

Jan 1, 1990

By E. C. Tarpley, R. A. Drogowski, R. F. Abernethy

Three of the test methods frequently used for the determination of moisture in the analysis sample of coal were employed in analyzing a series of coals ranging in rank from anthracite to lignite . For most coals , the variation between the three methods are within the tolerances allowed between duplicate determinations by the same method . The processing variables studied included atmosphere , flow rate of atmosphere , inert atmospheres , oven temperatures , heating time , exposure of the dried coal to laboratory air , and surface area of the test sample . Unless close control is kept on these variables , erratic results will be obtained .

Jan 1, 1964

By John G. Kovac

A computer simulation has been developed to estimate the chances of a miner making a successful escape while wearing a SCSR. The model takes into account: (1) training in the use of SCSRs, (2) apparatus integrity, and (3) the oxygen cost of a mine escape. This Bureau of Mines report examines survival odds for a prototypical escape, and illustrates how these odds change when SCSR training is improved.

Jan 1, 2009

By William R. Wayment, David E. Nicholson

A modified percolation - rate test is proposed for use in determining flow rates through hydraulic backfill ; in contrast to the conventional test , a percolation- rate versus void - ratio relationship is established . requirements and a detailed test procedure are described . Equipment Results of a conventional test are compared with those of the proposed modified test . The proposed modified test method yields more accurate , realistic , and usable percolation- rate ( permeability ) data . The significance of obtaining accurate percolation rates for use in analyzing waterflow through hydraulic backfill is discussed .

Jan 1, 1964

By J. S. Dunning

The objective of this research by the U.S. Bureau of Mines was to determine the effects of AI additions on the sulfidation resistance of Fe-Cr-Ni alloys. A series of Fe-Cr-Ni alloys with and without -additions of 4 pet AI were tested in a wet S vapor atmosphere at 677 C. A study of the morphology and composition of corrosion scales indicated a different corrosion mechanism for AI-free alloys compared with AI-containing alloys. Aluminum-containing alloys formed a compact, tightly adherent layer at the metal-scale interface that reduced corrosion rates by a factor of 3 to 10 compared with that of AI-free alloys. The thin, adherent AI-containing scale limited inward diffusion of 0 and S to the base metal and outward diffusion of Ni from the base metal. Aluminum-containing alloys formed a three-layer scale in oxidizing-S environments, while AI-free alloys formed a less protective two-layer scale.

Jan 1, 1989

By Robert M. Strong

The following report is a summary of the commercial results which 'Were obtained from 2,000 tests conducted by the technologic branch of the United States Geological Survey at St. Louis, Mo., and Norfolk, Va., in 1907 and 1908, under the technical supervision of R. H. Fernald, engineer in charge of the producer-gas section. The tests dealt primarily with gasoline, forming part of the investigation of mineral fuels provided for by acts of Congress. To determine the relative economy and efficiency of gasoline it was compared with denatured alcohol. The tests, many of which were undertaken in connection with work for the Navy Department, supplemented, to a certain extent, the work of previous investigations, but only so far as was necessary to emphasize some of the more important points and to lead up to the defining of conditions required for the economical use of gasoline and alcohol. In order to determine and eliminate the affecting engine conditions as far as possible, the investigation was commenced by making comparative gasoline and alcohol tests on the same engines. These tests were repeated on other engines of approxiElately the same size and speed, having different degrees of comFression, different methods of governing, and different carburetors. The final report will include much material that may be of use in engine design, but that side of the investigation was not pursued any further than was necessary to obtain the best possible results, for alcohol and for gasoline with the engines at hand, and to prove that the minimum fu·el-consumption rate for each could be obtained in approximately the same manner. The effects of engine and of operating conditions both have a bearing on the commercial deductions but will be discussed only in a general way at this time.

Jan 1, 1911