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By W. H. Lewis

This Bureau of Mines report and its companion report (Information Circular 9074) have been prepared as a complete reference on underground coal mine lighting. This report discusses the fundamentals of light and its interrelationship with the visual process. The purpose of the report is to insure an understanding of the numerous complex and interrelated factors that must be considered to design and implement a mine lighting system that will satisfy human needs for good vision and comfort. Topics include history, objectives, and technical considerations of coal mine lighting; light physics; light and vision relationships; and disability and discomfort glare.

Jan 1, 1986

By D. Bienstock

A high-B.t.u, gas can be synthesized by the catalytic methanation of a mixture of 2.5 to 3 parts of hydrogen to 1 part of carbon monoxide, obtained in the gasification of coal, using a steel catalyst followed by Raney nickel in a hot-gas-recycle system. Conversion of 99 percent of the H2+CO yields a fuel gas with a heating value of 983 to 1130 B.t.u. per cubic foot containing 78 to 96 percent methane, no carbon monoxide, and very small amounts of unsaturated hydrocarbons. With the steel catalyst alone, conversions were 85 to 90 percent, giving a fuel gas of 810 to 868 B.t.u, per cubic foot, or 847 to 975 B.t.u. on a C02-free basis. INTRODUCTION In 1948 the U.S, marketed production of natural gas was 5.15 trillion cubic feet; by 1958 it had reached 11.0 trillion cubic feet, a rate of growth of 8 percent annually. 4 5 Although demand is expected to increase less rapidly, by 1966 it may reach 16 trillion cubic feet, based on an estimated 4.7 percent annual increase.6

Jan 1, 1961

By Harold P. Rue

The problem of removing hydrogen sulphide from natural gas has become within the last few years one of major importance to the natural gas and petroleum industry. Several gas fields in the United States produce natural gas containing hydrogen sulphide, and a number of oil fields produce gas which contains hydrogen sulphide. 3 The percentage of hydrogen sulphide in natural gas produced in these fields varies from a fraction of 1 per cent to as high as 20.5 per cent by volume. Hydrogen sulphide is probably the most toxic gas associated with natural gas, and from the standpoint of health and safety it is important that the hydrogen sulphide be removed if the gas is to be used for domestic purposes. Hydrogen sulphide, besides being toxic and therefore a hazard to animal life, is under certain conditions an active corrosive agent and very destructive to equipment. The annual loss caused by the corrosive action of hydrogen sulphide on equipment amounts to hundreds of thousands, perhaps millions, of dollars. The largest percentage of natural gas produced in the United States comes from wells which also produce oil. This associated gas invariably carries with it light fractions of petroleum, which when separated from the gas, condense to the liquid form at ordinary temperatures and pressure. Commercial application is made of this natural condition, and "wet gas" is processed to obtain so-called natural gasoline by employing the principles of absorption, adsorption, or compression and subsequent expansion accompanied by cooling. In the manufacture of natural gasoline from wet gas which contains hydrogen sulphj.de, if this contaminating gas is not first removed, some of the hydrogen sulphide may oxidize to form free sulphur and water. The free sulphur will dissolve in the gasoline produced by any of the aforementioned methods and cause the product to be positive to the corrosion test and there-fore unsuitable for commercial use in that condition. The objectionable sulphur compounds can be removed by washing the gasoline with a solution of caustic soda or other chemicals, but this treatment is expensive. It is advantageous therefore to remove the hydrogen sulphide from the gas before it is processed in a natural-gasoline plant.

Jan 1, 1932

By T. H. Jeffers

The Bureau of Mines conducted laboratory tests to devise a procedure for extracting copper from low-grade discarded mill tailings. A solid extractant consisting of an organic solvent extraction reagent adsorbed on granular activated carbon was investigated and proved to be satisfactory for extracting copper directly from leach pulps. When this material was used in a cyclic leaching, stripping, and electrowinning pro-cess, 95 pct of the acid-soluble copper was recovered from oxidized mill tailings. The weathered tailings contained 0.24 pct Cu (total) and 0.20 pct acid-soluble Cu. The copper was recovered as cathodes containing, in parts per million, 1.6 Pb, 3.6 Fe, 0.5 Sb, 1.5 AI, 1.9 Mn, and <1 Mg.

Jan 1, 1985

By Rex D. Thomas

Concentration of the kerogen (organic material) in oil shale was accomplished by centrifuging after pretreating the oil shale with carbonic acid to remove the carbonates and pretreatment with sodium hydroxide (pH 11.5) to remove the claylike minerals. Analysis of the materials obtained showed that the concentrations of organic sulfur and organic nitrogen compounds were not affected by centrifuging. These compounds are evenly distributed in the kerogen and are not strongly bound to the mineral constituents. Organic oxygen compounds, however, were concentrated in the light fraction. These compounds are more closely associated with the kerogen and are not bound to the mineral constituents. Iron compounds other than pyrite apparently are closely associated with the organic material.

Jan 1, 1970

By Walter Pajalich

This Bureau of Mines report is a study of the organizational framework of the ferrous scrap industry, of the products produced, and of the factors affecting the consumption of ferrous scrap by the steel industry. Consumption data from 27 major iron and steel firms in the States of Illinois, Indiana, Iowa, Michigan, Minnesota, and Wisconsin during the period between 1957 to 1962 were grouped by type of iron and steel furnace production facilities to determine consumption pattern for various grades of scrap in comparison to ingot production, hot metal consumption, and home scrap generation. Grades of scrap affected by changes in scrap consumption were determined, and the pattern that emerged was analyzed. Correlation of scrap demand and its effects on scrap prices based on price of scrap receipts of No. 1 heavy melting scrap and No. 2 bundles in the Chicago area for the years 1957 through 1962 indicated that demand trends do not always affect the price of scrap, Past and present technological advancements in steelmaking processes are discussed, and their effects on the scrap industry are analyzed.

Jan 1, 1967

By J. G. Walters

This bulletin presents, in collected and tabluated form, Bureau of Mines and American Gas Association (EM-AGA) carbonization data pertaining to the chemical analysis of tars and the characterization of tars and light oils obtained from U.S. coals.

Jan 1, 1967

By Walter W. Fowkes

Leonardite is a coallike substance, similar in structure and composition to lignitic coal and believed to be derived from lignitic coal by the process of natural oxidation. Leonardite is little known outside lignite-producing areas and has been developed commercially only to a minor extent. The higher oxygen content and less compact structure of leonardite, compared with lignite, make it undesirable as a fuel but indicate that it has potential as a source of chemicals and for other nonfuel uses. It is a convenient source of humic acids. The United States has a large natural reserve of leonardite; furthermore, it can be produced in the laboratory under controlled conditions. The significant elemental difference between leonardite and lignite is the oxygen content (leonardite, 28-29 percent; lignite, 19-20 percent). The higher oxygen content of leonardite is due entirely to a Larger number of carboxylic acid groups. This fact explains the 17-Cold increase in alkali solubility of leonardite. Spectral studies indicate that the material is mixed salts of humic acids.

Jan 1, 1960

By William H. King

The Nevada Massachusetts tungsten deposits (fig. 1) are in the Mill City Mining District in north-central Pershing County, Nev., about 37 miles southwest of Winnemucca. Contact metamorphism of thin limestone beds within a series of metamorphosed sedimentaries formed scheelite-bearing ore bodies. These deposits are distributed over a wide area. A Bureau of Mines development program was started January 11 d was completed on July 25, 1941. This work was centered on the outer and less explored beds in the district and comprised trenching, sampling, and diamond drilling. Exploratory work was done in cooperation with the U.S. Geological Survey. Project work substantially increased the reserve tonnage of marginal ore in three of the areas explored and proved the nonexistence of tungsten in a fourth area. The following pages summarize the history of the district, outline property ownership, and describe physical features and ore deposits. The plan and results of the work performed by the Bureau of Mines are presented along with geologic and topographic maps, assay maps, and diamond drill-hole logs.

Jan 1, 1950

By Eldon K. Stanek

The material presented in this chapter is a review of the work done during the period from June 23, 1972 to June 22, 1973 which was reported in detail in the first annual report for Grant No. 60122088 which was submitted on June 29, 1973. This report has appeared in the National Technical Information Service as bulletin number PB230 972/AS. 1.2 ANALYTICAL PREDICTIONS OF INDUCED VOLTAGES AND CURRENTS The basic building block in this analytical work is the development of an equivalent circuit. The equivalent circuit for the cable depends on all of the distributed parameters of the cable, although the series inductance and resistance are of primary importance. The cable resistances are generally available from handbooks or from cable manufacturers. On the other hand, the cable inductances are not usually available from either handbooks or the manufacturer&apos;s published data. Thus, it is useful to present the results of the derivation of the inductance matrix and a few intermediate steps.

Jan 1, 1975

By Robert H. Ridgway

This circular outlines salient facts regarding the sulphur industry of the United States and the world. It is founded chiefly upon published information available in the literature of the subject. The Bureau of Mines has in its files additional, more detailed data upon many of the topics presented very briefly here, and will endeavor to assist the mineral industries and the public by giving further information in response to individual inquiries. It will welcome comments, criticisms, and contributions of data that may assist in making later editions of this circular more accurate, or in developing more fully the bureau&apos;s mineral files pertaining to sulphur. Throughout this paper sulphur is used to designate crude sulphur or brimstone, not sulphur produced from pyrites or&apos; smelter gases.

Jan 1, 1930

By Otto Ruhl

The Oronogo-Webb City-Duenweg district is in the northeastern part of the Tri-State zinc and, lead field. Its metal-mining history dates from the early 1850&apos;s. For some years prior to 1918 it ranked as the leading producing area of the entire Tri-State field, but by 1920 most of its mines had been abandoned and allowed to fill with water. Its mine operators had-been attracted, to the newly discovered and richer deposits around Picher, Okla. In 1943, the Orenogo Mutual Mining Co. was exploiting the Oronogo Circle deposit in the northern end of the district, and the Federal Mining & Smelting Co. was preparing to mine on its holdings in the southern part near Duenweg. The area between these two operating units ranked as the largest single block of ore reserves under water in the Tri-State field. In 1942, engineers of the Bureau of Mines, in collaboration with the William Stewart Engineering Co. of Joplin, collected all available mine maps, mine reports, and logs of old drill holes in the inundated area. From a careful study an appraisal of these data, the reserves in the block were calculated at 20,647,800 tons of ore containing 606,440 tons of 60-percent zinc concentrates and 46,970 tons of 80-percent lead concentrates. The ore was estimated to contain 1.76 percent recoverable zinc and 0.18 percent recoverable lead.

Jan 1, 1949

By Fred D. DeVaney

The Mesabi iron district of Minnesota has a potential production of over 50 million tons of iron are annually. The large shipments of ore each year are gradually depleting the reserves, and if the present rate of production is to be maintained there must be a growth in the present available ore supply. Growth is a natural course. The growth of a city may be affected by the addition of city blocks or by the improvement of utilities necessary for its betterment. These may go on in the order named or concurrently. The city-block type of growth of the Mesabi has been tremendous, and the "betterment" type has followed in due course. Probably the former has reached its limit, and if so, more time will be allotted to the latter. It is not the in¬tent of this paper to present either a eulogy of the wonderful mining methods or a history of the milling, but it is pertinent to say that if the lean-ore area continues to produce, the continuance will be more the result of further improvement of milling methods non well under way than of extension of boundaries by the city block plan of growth.

Jan 1, 1932

By H. D. Hess

This report describes in detail a unique occurrence of fersmite, (Ca, Ce, Na) (Cb, Ti, Fe, Al)2 (0, OH, F)6, which occurs as small anhedral inclusions and intergrowths with a tantalum-free columbite found in the metamorphic complexes of Ravalli County, Mont. Chemical and crystallographic data along with the physical and optical properties agree in general with those given in the original description of fersmite from the Ural Mountains of Russia. X-ray diffraction data not given in the original description and more specific optical data have been determined. The Montana fersmite, now established as the second occurrence of this rare calcium-columbate mineral, was discovered during a routine Bureau of Mines mineralogical examination of a prospector&apos;s sample.

Jan 1, 1960

By M. P. Youker

USE OF LOW-PRESSURE GAS BURNERS IN OIL- FIELD BOILERS

Feb 1, 1922

By Alan G. Mayton

Exposure to whole-body vibration (WBV) and the postural requirements of the job have been identified as important risk factors in the development of musculoskeletal disorders of the back among workers exposed to a vibratory environment. This paper focuses on preliminary results of WBV data collected for two groups of haulage trucks ? four older trucks from manufacturer A (MFR-A) and two newer trucks from manufacturer B (MFR-B). All of the trucks and their respective seats were considered to be in good working order during the study. Measurement periods for the truck groups had similarities, but varied from 2 to 58 minutes. Sampling times for the older trucks included a mean of 19.5 minutes and a standard deviation (STD) of 6.5 minutes compared to a mean of 40.8 minutes and a STD of 12.1 minutes for the newer trucks. Data collection coincided with the approximate delivery and first operation of the new trucks, and occurred approximately 12 months apart under similar weather and road conditions, and with the same drivers except an additional driver was included with the older trucks. Truck routes were somewhat different in that quarry production had changed location in the time between data collection activities. Overall, the results suggest that the newer trucks may provide better overall isolation to drivers/operators from WBV exposure compared to the older trucks operating at the quarry; although, this will need to be confirmed with additional measurements. Considering the higher variability and shorter sampling times for the older trucks, the results should be viewed with caution. For two of seven trials, the older trucks showed that seats amplified vibration, i.e., a transmissibility (T) >1.0. Seat T for the older trucks ranged from 0.31 to 1.17 with a mean of 0.77 and STD of 0.32. This contrasted with the newer haulage trucks where seats amplified vibration in 3 of 8 trials. In this case, T did not vary greatly and ranged from 0.87 to 1.05 with a mean of 0.97 and STD of 0.07. Regarding older trucks, in five of seven trials, the seat (output) data of weighted root-mean square (RMS) acceleration (wRMSZ) for the dominant z-axis exceeded the action level of 0.5 m/s2 action level recommended by the European Union Good Practice Guide for WBV (EUGPG) and levels exceeded the recommended exposure limit of 1.15 m/s2 in two of the seven trials. The wRMSZ values for the older trucks varied from 0.41 to 1.83 m/s2 with a mean of 0.99 and STD of 0.57. Similarly, newer trucks indicated a narrower range of wRMSZ from 0.38 to 0.95 m/s2. The mean wRMSZ was lower for the newer trucks at 0.58 m/s2 with a STD of 0.23 m/s2. Similarly, newer trucks indicated wRMSZ reached or exceeded the action level in four of eight trials. None of the trials with the new trucks showed wRMSZ levels that reached or exceeded the recommended 1.15 m/s2 exposure limit. As an indicator of driver/operator discomfort, overall weighted total RMS acceleration (vector sum) values seem to show a ?rougher? ride for the older trucks. The vector sum values for these trucks ranged widely from 0.70 to 2.59 m/s2 and, in four of seven trials, showed levels greater than 1.40 m/s2. The mean vector sum was 1.44 m/s2 with a STD of 0.75 m/s2. Comparatively, the newer trucks exhibited less variation with a range from 0.69 to 1.59 m/s2. The mean vector sum was 1.02 m/s2 with a STD of 0.35 m/s2. Vibration dose values for the dominant z-axis (VDVZ), gave a sense of vehicle jarring/jolting conditions. All trials with the older trucks were within the recommended EUGPG action level of 9.1 m/s1.75. On the other hand, in three of eight trials, both newer trucks exceeded this action level with values of 9.18, 12.58, and 13.21 m/s1.75. Neither truck group showed VDVZ that exceeded the exposure limit of 21 m/s1.75. A statistical analysis was not conducted, since the differences reported between truck groups may not be statistically significant owing to the relatively small sample size. Road conditions, changes in the truck routes, and driver/operator differences (e.g., stopping and turning) are possible factors in the higher VDV for the newer trucks.

Jan 1, 2008

By G. Richards Gwinn

Vermiculites are secondary minerals formed by the: alteration of biotite and philogopite mica and are associated with basic rocks such as dunites, serpentines, and pyroxenites. Vermiculite was first described by T. H. Webb in 1824. It remained a mineralogical curiosity until 1913, when the first commercial deposit was discovered in the Turrett mining district of Colorado. Expanded or exfoliated vermiculite was first marketed in 1915 from a deposit in this district 5 miles southeast of Hecla, Colo. This activity was brief, but successful and continuous commercial development began in 1921 in Montana. &apos;Deposits in other States have been found and developed, but Montana is by far the largest producer. Vermiculite has also been found in South Africa, Western

Jan 1, 1944

By Beverly W. Dunning

The effect of vacuum melting on the elimination of gases and nonmetallic inclusions for six low-alloy steels was investigated. The purpose of these studies was the analysis and comparison of differences in gas content and inclusions in air-melted and vacuum-melted steel. Data obtained from melts of 1-1/4 to 20 pounds indicate that vacuum melting decreases the number and size of nonmetallic inclusions and at the same time increases the degree of dispersion of the remaining inclusions. These improvements are undoubtedly related to the elimination of approximately 80 percent of the nitrogen and 90 percent of the oxygen as well as most of the undesirable metallic trace impurities.

Jan 1, 1961

USBM Contract H0133045 consists of the design, build and test of 50 waveform generators. The waveform generator is a small ULF transmitter operating in the 1 to 3 KHz frequency range for the purpose of locating trapped miners during a mine disaster. This contract provided for the design, test, and building of 50 waveform generators using a discrete component construction with an option of using hybrid construction techniques within 105 days after the effective date of the contract. Because of large quantity economic considerations, this option was not initiated. Two engineering models were designed, constructed and tested and 50 final production units were fabricated using discrete construction. Complete documentation is supplied under a separate package which includes final schematics, parts list, layout information, equipment specification, production test procedures and qualification test procedures. Ten units have been delivered to the USBM. The remaining 40 units are being retained for packaging under contract H0242010 Transmitter Package and Receivers.

Jan 1, 1974

By A. B. Hooker, L. C. IlsLey

"The last previous Bureau of Mines publication relative to details of permissible electric mine lamps is Bulletin 332, which describes 16 lamps approved prior to May 1930. Some of the lamps have become obsolete through the development of improved models which, with several new types, make it desirable to supplement the Bureau's published data relative to permissible electric mine lamps.In the following descriptions, lamps approved since May 1930 and prior to July 1, 1935, are placed in the three following groups: (1) Electric cap lamps, (2) electric hand lamps, and (3) lamps for miscellaneous applications,ELECTRIC CAP LAMPS APPROVED UNDER SCHEDULE 6B1. Edison model J lamp, approval no. 24. - The features that distinguish this lamp from earlier models of Edison electric cap lamps are:(a) The battery consists of two F-2 cells of square cross section and about 1-1/4 inches higher than M-14 cells in the model H lamp, making the battery narrower and higher than any of the earlier models of Edison cap lamps.(b) The cells are insulated from each other and the Monel-metal casing by enclosure in vulcanized-rubber baglike enclosures. Both cell terminals are insulated from the cell jar.(c) The battery is equipped with rubber-tube Bunsen-valve-type gas vents.(d) The battery casing is secured by a new-type magnetic lock.(e.) The battery and cover terminal clips have been redesigned to give a wiping contact."

Jun 1, 1936