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By J. A. Cooper

The objectives of this research were to define the chemical composition and physical characteristics of the aerosols associated with attached radon daughters in operating uranium mines, and to investigate the relationship between these aerosol parameters and operating conditions. Major Results and Conclusions The organic, inorganic and radiological characteristics of test chamber and active U-mine aerosols have been measured as a function of particle size. These measurements represent the first detailed analyses of the organic and inorganic components in U-mine aerosols and the first determinations of the details of the individual and total radon daughter distributions in operating U-mines. The following is a list of the major results and conclusions:

Jan 1, 2012

By G. Gavan

Analysis of reported injuries for off-highway haul trucks indicated that 42.7% were slip and fall, and of these 34.1% occurred mounting and dismounting the machine. Redesign of the lower steps was concluded to provide the most overall improvement for increased safety and accident reduction. Various existing, innovative and conceptual designs were reviewed and evaluated. The most promising candidate designs were the four-spring supported lower steps and the center tube mounted lower steps. Both configurations proved to be viable designs as they passed successfully human factors and survivability tests conducted at a large copper mine.

Jan 1, 1979

By GEORGE T. Harley, Walter R. Storms

This paper, which describes mining mothods at International Minerals & Chemical Corp, 'e. potash mine. in. Eddy. County, N. Mex., is one of a sories being prepared by the Mining Branch of the Bureau of Minos. on mining method a and practicos in, various mining districts of the United States. The mine shafts and. surface plant or International Minerals & Chemical Corp. are situated. in. sec.. 12, T. 22 S., R. 29 E., N. M. P. M., about 26-1/2 miles by paved highway east of the city of Carlsbad (figs. 1, 2, and 3). A spur line of the Atchison, Topeka & Santa Fe Railroad connects the mine with the Clovia-Pecos branch of the same road near Loving, a few miles south of Carlsbad. This spur also serves the refinery of United Staics Potash Co. This report gives. the history and describes the geology of the district. Methods of prospecting, exploration, sampling, and estimation of tonnage and values are explained; development and mining methods are discussed in con- siderable detail; transportation, ventilation and drainage are outlined; safety measures are noted; and the wage scale and organization are mentioned.

Jun 1, 1949

By Seth C. Schaefer

The Bureau of Mines studied thermodynamic properties of Al-Ni alloys con¬taining 0.54 to 30.04 atomic percent nickel with the aid of the high-temperature galvanic cell Al(1) // Al+3 (AlCl3 in NaCI.KC1) // Al-Ni alloy (1 or s). Activities of aluminum and nickel (compared with pure liquid metals as the standard state) show pronounced negative deviation from Raoult's law at 1,273 K. The properties [?G, ?Gxs, ?G ideal, ?GA1, AGxs1, ?Gni , and ?GNixs] have been derived from the experimental data and are summarized in tables and illustrations. At 1,127 K, the thermodynamic stability for the invariant three-phase equilibrium consisting of a saturated liquid, A13Ni, and A13Ni2 has been uniquely defined by an activity for aluminum of 0.751. A free energy of formation at 1,127 K of -7,940 cal/g-atom was derived for the compound A13Ni.

Jan 1, 1975

This report presents the results of a study of mill tailings disposal practices and potential tailings dam stability problems. Recognizing the long period of time that would be required to develop the technology and practices necessary to significantly improve refuse disposal safety, the Bureau initiated this research effort as a first step in that development. Volume 1 includes a summary of conclusions and recommendations resulting from the overall research effort; discussions of disposal systems and methods, geology, seismicity, hydrology, and materials characteristics; evaluations of investigational techniques; discussions of usable interim generalized investigational, analytical and inspection procedures; discussion of general principles and presentation of a tailings technology manual outline; and discussion of needed future research am recommended programs.

Jan 1, 1974

By E. D. Gardner

This bulletin, which discusses open-cut mining at the metal mines of the United States, is the last of a series of such papers by the Bureau of Mines describing the principal methods of mining.4 Open-cut mining is applicable to flat-lying mineral deposits relatively near the surface. Vein deposits seldom are amenable to this method, although outcrops of veins sometimes are worked as open pits. Most of the iron ore of the country is mined from open pits; according to the Minerals Yearbook, 67.4 percent was mined from open pits and 32.6 percent from underground mines in 1937. Open-cut mining is relatively new in the copper industry but yields more copper than any other method; in 1937 about 52 percent of the copper ore mined in the United States was taken from open pits. Lead-zinc ore has been produced from open pits in the Joplin (Mo.) district, but most of the deposits in this area, although flat-lying, are too deep to be mined economically by the open-cut method. In 1937 one company at Oronogo, Mo., was stripping overburden and mining mixed oxidized and sulfide ores by this method.

Jan 1, 1941

By Gilbert L. Forst

The objective of this program is to identify and evaluate superior, lightweight substitutes for selected coal mine roof support concepts such as crossbars, posts, and crib blocks. Engineering analysis and concept design identified, through tradeoff studies, that some materials are promising, from a technical standpoint, as support substitutes: E-glass reinforced polyester resin, high strength low alloy steel, aluminum, and very high early strength (VHE) cement. An economic analysis indicates that none of the lightweight substitutes are economically competitive with wood on an initial cost basis; however, in terms of life cycle costs based on current dollars, the high strength low alloy steel appears competitive for crossbars, and the VHE cement and E-glass/resin appear competitive for posts.

Jan 1, 1978

By D. H. Desy

The Bureau of Mines studied the properties of copper that had been oxide dispersion-strengthened with 2 vol pct of either yttria or alumina. Compounds of copper and aluminum or yttrium, coprecipitated from aqueous solution, were converted to oxides; the copper was reduced, compacted, sintered, and extruded. For the resulting copper-dispersoid composites, room temperature tensile properties after annealing in hydrogen, elevated temperature tensile and stress-rupture properties, and electrical conductivity were determined. Compared with oxygen-free copper, copper-2 vol pct alumina or yttria had improved strength after annealing between 400° and 1,000° C, and improved elevated temperature strength, with little loss in electrical conductivity.

Jan 1, 1969

By S. H. Lorain

This paper briefly describes the principal commercial and near-commercial deposits of gold-bearing gravel and the important placer-mining operations in Lemhi County, Idaho. It is on of a series on western mining districts being published by the Bureau of Mines. This paper is based on a field survey of the placer-mining districts of Lemhi County in the summer of 1938. Available information concerning gold-bearing gravels was obtained from prospectors and claim owners; operators supplied the data on mining operations. No attempt was made actually to test the gravels. The principal object of the examination was to indicate placer areas worthy of further investigation by prospective operators.

Jan 1, 1939

By Others, C. M. Weld

During the past two years the Bureau of Mines has issued a series of mimeographed reports giving the results of research work and experiments conducted as part of its war minerals investigations. In this bulletin the reports on manganese are presented, which range in scope from the beneficiation of the ore to the utilization of the metal. The bulletin is in eleven chapters, each comprising a separate report, arranged in the order given below. 1. General information regarding manganese, by C. M. Weld. 2. Uses of manganese other than in steel making, by W. C. Phalen. 3. Problems involved in the concentration and utilization of domestic low-grade manganese ores, by Edmund Newton. 4. Preparation of manganese ore, by W. R. Crane. 5. Leaching of manganese ores with sulphur dioxide, by C. E. Van Barneveld. 6. The Jones process for concentrating manganese ores; results of laboratory investigations, by Peter Christianson and W. H. Hunter. 7. Cost of producing ferromanganese ores, by C. M. Weld and W. R. Crane. 8. Production of manganese alloys in the blast furnace, by P. H. Royster. 9. National importance of allocating low-ash coke to the man- ganese-alloy furnaces, by P. H. Royster. 10. Electric smelting of domestic manganese ores, by H. W. Gillett and C. E. Williams. 11. Use of manganese alloys in open-hearth steel practice, by Samuel L. Hoyt. As each chapter was originally prepared as a unit, there is neces- sarily some duplication and overlapping. With certain exceptions, however, each paper is reproduced in practically its original form. In chapter 1, covering certain general phases of the industry, such as uses, specifications, prices, and statistics, the subject matter has been somewhat modified in view of changes in conditions.About 95 per cent of the manganese consumed in the United States goes into the manufacture of steel. The remaining 5 per cent is used in a number of minor industries, the chief of which is the manufacture of dry cells. These minor uses are described in chapter 2. No discussion of the geology of manganese eres is presented, but a short bibliography on the subject is appended. With few excep- tions the manganese deposits of the United States are irregular, pockety, and uncertain. Largely for this reason, mining methods are crude and hardly warrant descriptions. The concentration of manganese ores, however, is an important problem and involves some details not common to other ores. Chapter 3 discusses the concentration and utilization of low-grade ones, notes the relationship of concentration to metallurgical prao- tices, outlines concentrating processes, and treats of commercial problems. In general, as regards concentration methods, manganese ores may be divided into two groups, as follows: (1) Ores permitting mechanical separation of the manganese minerals and the gangue, and (2) ores in which the manganese minerals and the gangues are so intimately associated that separation requires some hydrometal- lurgical or pyrometallurgical process. Heretofore, attention has been confined almost wholly to mechanical separation, chiefly by gravity. In fact, so far as known, all production of concentrates has been by wet gravity methods, although during the war some companies investigated the commercial pessibilities of magnetic separation and reported favorable results, the construction of one magnetic con- centration mill being started. The usual wet gravity methods are described in chapter 4. During the war, the Bureau of Mines undertook investigations of methods applicable to ores of group 2. A hydrometallurgical process involving leaching with sulphur dioxide was studied at the mining experiment station of the bureau at Tucson, Ariz. The results of this work, presented in chapter 5, indicate that the process is metallurgically feasible but the cost makes it unattractive. The results of an investigation of a pyrometallurgical process known as the Jones process are presented in chapter 6. The process, which is still in the experimental stage, was found to be metal- lurgically sound. The manganese product is not a concentrate but an alloy, made directly from a lean unconcentrated ore. The custom- ary method is to manufacture alloys from high-grade ores or from concentrates of leaner ores. A discussion of the costs of ferro-grade manganese ores is pre- sented in chapter 7. This discussion is in general terms only, but should be of use in so far as it relates to competitive conditions.

Jan 1, 1920

By S. H. Ash

NO MORE important question has come before the coal-mining industry in many places, especially in the anthracite region of Pennsylvania, than prevention of stream pollution by mine drainage. Available information on acid mine drainage in the anthracite region of Pennsylvania indicates that a pollution problem must be solved in any program of anthracite mine drainage. The major problem concerns satisfactory disposal of the daily average mine-water discharge of 327,000 gallons per minute (g. p. m.), or 472 million gallons per day (g. p. d.), containing a free-acid load of 431 tons or a total acid load of 934 tons a clay as H2S04. This report indicates the scope of the problem and gives some suggestions concerning its solution.

Jan 1, 1951

By R. J. Leary

The Bureau of Mines experimental blast furnace was blown with oxygen-enriched blast in combination with natural gas injected at the tuyeres. The air blast was augmented with oxygen to form an enriched blast containing 24,8 pct oxygen, and tests were run at natural gas injection rates of 4.5, 6.0, and 8.3 pct of the air blast. Similar enrichment to 26.8 pct oxygen was tested at natural gas rates of 7.2, 9.1, and 11,0 pct of the air blast. At intermediate proportions of natural gas to oxygen, (1) the fuel rate and the replacement ratio of coke by natural gas were unaffected by oxygen injections and (2) the productivity increased about 4 pct for each I pct oxygen added to the blast. The higher proportions of natural gas to oxygen were less efficient; in return for a lower coke rate, the fuel rate increased and productivity declined. A deficiency in reducing gas imposed a limit upon lower than normal proportions of natural gas to oxygen. Beyond this limit the formation of reducing gas was insufficient to support the rate of metal production. When this condition was encountered, the coke rate requirement for specification iron was abnormally high and production fell off badly. Adiabatic flame temperature is discussed as a means for proportioning oxygen and natural gas additions.

Jan 1, 1967

By W. H. Oppelt

To provide a relatively structurally stable form of dried lump lignite, two North Dakota lignites from Mercer County were dried by the Fleissner process in an atmosphere of saturated steam at 200, 300, and 370 p.s.i.a. pressure, corresponding to steam temperatures of 382°, 417°, and 437° F., respectively. Two series of experiments were made at each test pressure with the individual lignites. In one series, the autoclave was preheated to the processing temperature before charging the lignite; in the other the lignite was charged into the autoclave at room temperature. In each case, heat losses were determined by blank tests of steam consumption over a similar operating cycle with the empty autoclave. The degree of moisture removal and net steam consumption were calculated from material balances. The amount of water removed as a liquid from the two North Dakota lignites during the heating and steaming periods was compared with results calculated from previously published data on drying Austrian lignite and Australian brown coal. These lignites, covering a wide geographical area, had original moisture contents ranging from 35 to 49 percent. The Austrian lignite and Australian brown coal are considered to be of Miocene Age, and the Dakota lignites belong to the Paleocene.

Jan 1, 1955

The 1965 Lignite Symposium, the Louth in a series and the third sponsored by the University of North Dakota and the Bureau of Mines, was held at Bismarck, N. Dak., on April 29-30, 1963. These symposia provide a forum for those interested in the technology and utilization of solid fuels, especially lignitic coals. As part of the meeting, a 200-mile field trip was taken including; inspection of (1) the 200-megawatt, pulverized lignit-fired Leland Olds plant of Basin Electric Power Cooperative, under construction near Stanton, N. Dak.; (2) the site of the Glunharold mine of the Truax-Traer Coal Co., Division of Consolidation Coal Co., where a wheel excavator was being assembled; (3) the operating Beulah mine of Knife River Coal Mining Co., subsidiary of Montana-Dakota Utilities Co., near Beulah, N. Dak.; and (4) the 400-megawatt, hydroelectric Garrison Dam powerplant, near Garrison, N. Dak.

Jan 1, 1966

By David Schlain

IN 1942 the Bureau of Mines began to develop the Kroll process for use in the large-scale production of titanium. Titanium and titanium alloys are now commercial metals. These metals are relatively expensive, but It is now evident that they will have important industrial uses and that in many instances these will be related to their remarkable corrosion resistance. This bulletin presents the known corrosion properties of titanium and its alloys in useful form. In marine environments titanium is highly resistant to corrosion and does not pit, or undergo crevice corrosion, stress corrosion, or corrosion fatigue. Titanium is also highly resistant in many salt solutions, including most chlorides. It is very resistant to corrosion in nitric acid solutions. It is also resistant to white fuming nitric acid. However, it may react violently with red fuming nitric acid. In phosphoric acid solutions titanium has rela¬tively good resistance to corrosion, but it has less resistance to sulfuric acid and still less to hydrochloric acid solutions. Titanium corrodes very rapidly in hydrofluoric acid Solutions. It is very resistant to corrosion in many organic chemicals. However, it has only moderate resistance to formic acid solutions and poor resistance inn oxalic acid solutions. Titanium does not corrode in dichloroaretic acid but, corrodes rapidly in 100 percent trichloroacetic acid at 100° C. Titanium is resistant to barium, calcium, magnesium, ammonium, and sodium hydroxides. Titanium is inert in wet chlorine, bromine, or iodine gases. However, in dry chlorine gas titanium reacts rapidly enough to ignite. It also reacts rapidly with dry bromine gas, but, it is resistant to dry iodine gas. When titanium is exposed to red fuming nitric acid solutions with high nitrogen dioxide content and low water content, it corrodes, undergoes stress-corrosion cracking, and becomes pyrophoric. This occurs more readily with some titanium alleys, such as titanium-8 percent manganese. A fresh titanium surface immersed in water or in an aqueous solution and in contact with an oxygen-rich atmosphere under sufficientt pressure is unstable and will ignite spontaneously. Inherently an active metal, titanium has a tendency to become less active in environments containing oxidizing agents such as air, oxygen, chlorine, or ferric, cupric, or platinic ions. Titanium is more noble than most structural metals in roost, environments and its excellent corrosion resistance is generally not, affected by contact with these metals. However, some of the other metals corrode faster because of contact with titanium. Titanium undergoes anodic polarization readily, so that even when it is the less noble member of a galvanic couple it may corrode less because of the contact. Titanium alloys often have corrosion properties and electrochemical characteristics similar to those of commercially pure titanium. Titanium alloys containing noble metals, zirconium, molybdenum, vanadium, tantalum, or copper sometimes have better corrosion resistance than pure titanium.

Jan 1, 1964

By V. R. Miller

The Bureau of Mines investigated methods for testing the tensile and sheer strength of cast specimens of bulk solder and of soldered joints in order to increase the strength and extend the useful temperature range of soft solders. A spread-area test for determining the wettability of solder on copper surfaces was developed. Mannitol was used as a flux in spread tests to control spreading and to avoid plating, etching, and other side effects of regular fluxes. Data on commercial and high-purity solders obtained by these methods show more consistency than those reported by others from similar tests.

Jan 1, 1967

By Winthrop F. Watts

The U.S. Bureau of Mines evaluated the performance of a catalyzed diesel particulate filter (CDPF) and a CDPF combined with a diesel oxidation catalyst (DOC) at two metal mines. This report describes the results from the two field evaluations. The CDPF-DOC was installed on a load-haul-dump (LHD) powered by a 175-kW, prechambered, turbocharged engine. This system reduced diesel particulate matter (DPM) concentrations by 71±28 pet, as determined by size-selective sampling with gravimetric analysis, and by 71±29 pet, as determined by respirable combustible dust (RCD) analysis at the vehicle operator's location. The CDPF was installed on a diesel-hydraulic, roof-bolting jumbo, powered by a 172-kW engine. The CDPF reduced DPM concentrations by 72±21 pet, as determined by size-selective sampling with gravimetric analysis, and by 62±25 pet, as determined by RCD analysis at the vehicle operator's location. Underground evaluation was more difficult because of frequent movement by the roof-bolting jumbo, variation in daily workload, tremendous fluctuation in ventilation airflow rates, and use of a high sulfur diesel fuel, which promotes the formation of sulfate particles, decreases filtration efficiency, and hastens the deterioration of the catalyst.

Jan 1, 2010

By Max F. Lee, Warren A. Peck

The applicability of the Q-system [Barton et al. 1974] to Australian underground metal mines is discussed with reference to two common design issues: ground support for horizontal mine development, and assessing the stability of bored raises. Installed ground support in mine development is com-pared to empirical estimates using the Q-system and associated support capacity calculations. Data are graphically presented from 59 specially selected sites at 15 contributing mines. The actual performance of large-diameter raise-bored shafts is also compared to empirical stability assessments using a modified version of Q (Qr, after McCracken and Stacey [1989]). Lower-bound Qr values are plotted against raise diameter for 47 selected sites at 23 mines in Australia and Papua New Guinea. The influence on Q and Qr of some geotechnical aspects of the Australian landscape, the dynamic nature of mines (compared to civil construction), and occupational health and safety regulations are discussed. Stability and support assessments that are based just on Q or Qr are not always conclusive. It is often necessary to consider other rock mass parameters, the regulatory environment, and risk issues. These results are interim; further data collection and analysis are required with regard to comparing actual performance versus empirical assessments.

Jan 5, 2007

By W. N. Hoskins

This report covers the final results of a two-phase contract study conducted between July 1974 and October 1976. A comprehensive summary of the initial phase of the study is included. Phase I of the study involved the investigation and evaluation of all potential candidate underground systems for mining the deeper deposits of oil shale and associated minerals in the Piceance Creek basin of northwestern Colorado. Phase II called for the refinement and the detailed technical and economic analysis of the most promising system, or systems, thus disclosed. Of the several systems initially investigated and evaluated, four showed considerable merit for exploiting the deeper deposits: (1) chamber and pillar mining with spent shale backfill, (2) sublevel stoping with spent shale backfill, (3) sublevel stoping with full subsidence, and (4) block caving mining using LHD's. Final refinement and analysis of these four systems indicated their technical feasibility over at least part of the range of conditions expected in the deeper deposits. Their economic feasibility also was indicated under certain operating and market conditions. A variety of engineering, production, and cost information is provided on each of these systems.

Jan 1, 1976

By Oliver C. Ralston, Dorsey A. Lyon

The data reported in this bulletin are largely the result of experiments conducted by the Salt Lake City station of the Bureau of Mines in cooperation with the department of metallurgical research of the University of Utah. The work on lead is only one of the phases of the investigations carried on at that station during the years 1914 to 1916. The results of similar work with zinc ores and with copper and other ores will be published in future reports of the bureau.

Jan 1, 1918