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By H. E. Powell

The selective recovery of nickel and zinc from a waste phosphate solution by solvent extraction was investigated by the Bureau of Mines as part of a broad program to recover valuable metals and compounds from industrial wastes, and to reduce the associated land and water pollution caused by dumping these wastes. The waste, which resulted from the phosphation of automboile bodies, yielded 99 percent of both the nickel and the zinc by extraction with dinonyl naphthalene sulfonic acid (DNSA) and di-2-ethylhexyl phosphoric acid (EHPA), respectively. Dilute sulfuric acid was used to recover the metals and regenerate the solvents.

Jan 1, 1970

By L. C. IlsLey

From time to time the Bureau of Mines has issued publications dealing with the various classes of explosion-proof mining machinery that have been tested and approved as permissible for use in mines having atmospheres that may become inflammable by reason of the inadvertent presence of gas or dust. These publications are confined almost entirely to description of the features contributing directly or indirectly to the prevention of explosion or shock hazards, and are intended to give inspectors, safety engineers, and others already familiar with the general safety requirements more detailed information on the safety features of the design of a particular machine. As a background for papers describing permissible machines and to avoid the necessity of duplicating descriptions of methods of conducting investigations and tests of such machinery, Bureau of Mines Bulletin 305, Inspection and Testing of Mine-Type Electrical Equipment for Permissibility, was published in 1929. Three bulletins giving detailed descriptions of the three most numerous types of machines have been issued, viz., Bulletin 313, Permissible Storage-Battery Locomotive and power Trucks. Bulletin 343, Permissible Coal-Handling Equipment. Bulletin 382, Permissible Coal-Cutting Equipment.

Jan 1, 1937

By John F. Papp

The Bureau of Mines has sampled microstructure of low-pressure flat flames by mass spectrometer for normal methane-oxygen-argon and for methane-oxygen-argon-bromotrifluoromethane flames. The physical and chemical phenomena, and the method of analysis of mole fraction data to evaluate net reaction rates are here considered in detail. Included is a computer program listing with output on one flame. Chemical species considered are CH4 , CO, CO2, H, H20, OH, Ar, H2, O2 , O, H2CO, CH3 , CF3Br, HF, HBr, Br, CH3Br, HCO, F2CO, CH2 CF2 , H02.

Jan 1, 1975

By A. W. Maynard

Simple chemical spot tests for the identification of major alloying elements in aluminum-base alloys are described. The tests are suitable for use by nontechnical personnel working outside a laboratory. Tests for zinc, copper, manganese, and magnesium employ electrographic sampling methods and sample papers. Use of electrographic sampling in a test for magnesium in aluminum is made possible by using glass fiber filter paper. Differentiations between magnesium and magnesium-silicon alloys of aluminum and between aluminum-base and magnesium-base alloys are made by direct chemical solution tests. Description of a device for obtaining reliable electrographic samples is included. A sequence of testing for identification by alloy groups is given.

Jan 1, 1971

By W. S. Anderson

The use of flexible liners for support of underground openings has been investigated by the Bureau of Mines. This report presents installation procedures and instrumentation results of a full-scale flexible liner field installation in the Burgin mine. The flexible liner is a part of the mine support system and has provided maintenance-free support for 22 months

Jan 1, 1975

By Richard F. Hewlett

The mining industry utilizes a vast store of knowledge, wisdom, and engineering talent in designing mining systems. However, the complexity of the required systems and the presence of numerous variables frequently necessitates raking important decisions without having adequate accurately detailed information. That many of the decisions made in the past were nearly correct, in the long run, is substantiated by the number of successful mining enterprises that exist in the world today. Subsequent to 1940, the disciplines of operations research and systems engineering were developed. The disciplines have produced methods of providing better information to persons responsible for making decisions.

Jan 1, 1963

By S. D. Sanders

Goals of the Bureau of Mines include utilizing readily available minerals as substitutes for scarce mineral commodities and minimizing occupational hazards associated with mineral processing occupations. Therefore, the Tuscaloosa Research Center investigated using rapid-set cement as a suitable molding sand binder for small ferrous castings; currently petroleum-based binders are used. Substitution of a rapid-set cement would eliminate organic vapors associated with the petroleum-based binders; these vapors constitute occupational hazards and environmental pollutants. A binder containing 60 percent white portland cement (WPC) and 40 percent calcium aluminate (CA) would be an acceptable and economic substitute for petroleum-based binders where the foundry requirements are compatible with its limitations. It produced a set time and a pattern strip time of less than 1 hour. Cement, sand, and water mixtures developed compressive strengths from about 40 to 75 psi after 2 hours and from 120 to 130 psi after 24 hours. Tensile strengths of 18 to 22 psi were obtained after 2 hours, increasing to 30 to 35 psi after 24 hours. The addition of about 1 percent polyphosphate to the sand-cement-water mixture doubled the compressive strength and increased the tensile strength about 50 percent after 4 hours, but also increased the set time from 30 minutes to 1 to 1-1/2 hours. Po1yvinylacetate (PVA) resin latex additions resulted in rapid strength development. When castings were poured into the cement-bonded molds, the surface finish was fair to good on gray iron castings, but some areas of burn-on were present on steel castings. Using a graphite wash on the cement-bonded molds produced good surfaces on gray iron castings.

Jan 1, 1979

By P. G. Barnard

The Nation's steel industry is largely dependent on shipments of manganese from foreign sources for steel production. An adequate substitute for the manganese requirements of our present steel technology would improve our national self-sufficiency and also contribute substantially to the conservation of our manganese resources. As each of these objectives is a major interest of the Bureau of Mines, possible substitutes for manganese in steel were investigated. Titanium was selected as the most promising substitute because the published results of several investigations indicate that titanium would perform the most obvious function of the manganese in steel: The elimination of iron sulfide and its deleterious effects. The investigation involved extending the published data on titanium additions in steel to provide enough information for an accurate evaluation of the practical value of the substitute. Therefore, quantitative data were obtained on the partition of sulfur and carbon between iron and relatively small titanium additions.

Jan 1, 1962

By Uldis Jansons

This report evaluates the economic Mining feasibility of four selected mineral deposit types that can be anticipated to be found in (d)(2) lands in the western Brooks Range, Alaska. The major assumption made for this study is the availability of a rail system for transporting equipment and concentrates for the base metal mines. Commodity prices used are those in existence in July 1976. Mine models were established based on known deposits and then evaluated. A lead-zinc-silver-barite deposit for which grades were available but ore reserves were assumed would require approximately 25% higher ore grades or higher metal prices to yield a 15% discounted cash-flow rate of return an the investment if mined at a rate of 10,000 tons per day open pit methods. Large copper-zinc mineral deposits could be mined economically at rates either of 5,000 tons per day underground or 10,000 tons per day by open pit methods. A high-grade copper deposit require a copper price of over one dollar ryes pound to yield an economic profit to be mined at 2,000 tons per day by underground methods. A small high-grade gold underground mine would require a gold price of about $295 per ounce to yield a 20% discounted cash-flow rate of return on investment if all new mine equipment were used and if existing labor rates were paid: Enterprising mining groups operating as partnerships might be able to operate this mine profitably at a gold price of about $152 per ounce, perhaps slightly less.

Jan 1, 2012

By Martin Hertzberg

The Bureau of Mines 8-liter flammability system was used to study the effectiveness of a variety of powdered inhibitors in preventing the propagation of explosions of coal dust or methane in air. Over 35 different chemical additives were evaluated against Pittsburgh seam pulverized coal. The least effective inhibitors were the carbonates, which required mass additions in the range of two to three parts inhibitor to one part of coal dust in order to prevent propagation. The most effective inhibitors were the derivatives of ammonium phosphate, which were effective quenching agents at additions of only one part inhibitor to four parts of coal dust. Alkali halide powders were of intermediate effectiveness. These laboratory-scale results are in good agreement with full-scale mine experiments in all cases where detailed comparisons have been made. Data were also obtained for the effectiveness of several of the same powdered inhibitors against methane-air explosions. Their relative order of effectiveness and the concentration ranges required for quenching the gas explosion are comparable to those measured for coal dust explosions. Data are also presented for the effectiveness of N2 and CF3Br addition. Some preliminary data are also presented for powder addition to methane burner flames. Those data are compared with other burner data and evaluated in terms of their relevance to explosion tests.

Jan 1, 1982

By Warren E. Morrison

The continuing high-level performance of the domestic mineral and mineral fuels industries during 1966 was sustained by the longest business upturn in the Nation's history. Spurred by consumer demand at home and the defense production requirements of the Viet-Nam war, the rising trend of economic activity during the year was reflected in the upward movements of the major economic indicators. At yearend the gross national product (GNP), representing the value of all goods and services produced, stood at $740 billion, $58 billion greater than in 1965. Corrected for price changes, the real value of GNP in terms of 1958 dollars was $648 billion and represented an annual increase in economic activity of 5.4 percent. Some 74 million persons were employed during the year out of a total population of 196.8 million, while unemployment fell below 4 percent. The Federal Reserve Index of Industrial Production averaged 156 for 1966, up 13 points from the previous year. However a jarring note in the 1966 expansion, and one which affected the mineral industries in particular, was the increasing pressure on prices and the threat of inflation. From 1961-65 economic growth was facilitated by relatively stable wages and prices and only mild inflation. During the period average wholesale prices hardly moved while average consumer prices rose only about I percent per year. But this long run of relative price stability ended during 1966 when consumer prices rose 2.9 percent and wholesale prices were up 3.2 percent from the previous year.

Jan 1, 1967

By R. V. Lundquist

The work described in this report, part of the Bureau of Mines long-range program to develop methods of utilizing submarginal domestic sources of aluminum, was undertaken to investigate the effects of iron in the lime soda sinter process, The approximate Fe2O3 content in a sinter for maximum alumina and soda recovery was 8 to 9 percent. Fe2O3 appears to inhibit gelation, and 15.5 percent Fe2O3 produces effects similar to those produced by 1 percent sucrose. In the lime soda sinter process, aluminum silicates are sintered with limestone and soda ash to yield dicalcium silicate and sodium aluminate. The sodium aluminate is extracted by leaching in caustic solution. The solution is purified by heating in an autoclave with lime to remove silica, and alumina trihydrate is precipitated with carbon dioxide. The reactions involved in sintering and leaching are complex. A number of studies by the Bureau of Mines4-9 and others1 indicate that the iron content of sinters influenced the recovery of alumina and soda and the gelation characteristics.

Jan 1, 1962

By H. V. Makar

A study was conducted by the Bureau of Mines to determine problems associated with the use of ferrous fractions from urban refuse as melting stock for steelmaking and to evaluate the resulting steel products. The study involved 50-pound ingots from laboratory melts and 50-pound ingots from 1-ton electric-arc-furnace melts. The 50 pound ingots from the laboratory melts and the arc-furnace melts were hot rolled to provide material for mechanical and corrosion testing. Results obtained in the study include the following: Most steels rolled successfully and exhibited acceptable surface and edge condition. Tensile strengths of the plain carbon steels were not significantly affected by copper up to concentrations of 0.65 pct and were not affected by tin content up to 0.16 pct. Yield strength increased with increasing copper and tin contents, and impact strength decreased with increasing tin content. Hardness increased slightly with increasing copper content. In general, properties of the steel produced were not measurably affected by charge composition (that is, melting stock), melting practice, or method of scrap preparation.

Jan 1, 1975

By Charles L. Kimbell

Available statistics on 1989 worldwide consumption of selected nonfuel minerals shown in table 5 show increases for 11 of 14 listed nonfuel mineral commodities with 1 unchanged from the 1988 level, a departure from the pattern of the past 2 years, in which each of the listed commodities registered gains. The 1989 results, however, were better than those for 1986 when only seven listed nonfuel mineral commodities recorded gains with one un- changed from 1985. Consumption of the two ferrous metal raw materials listed advanced as functions of increased output of pig iron and crude steel. The increase in iron ore consumption exceeded the increase in iron ore output, suggesting a slight drawdown of world iron ore inventories. The estimated in- crease in iron and steel scrap consumption was slightly greater than the minuscule increase in world steel production, but it is believed that there was little change in the ratio of iron ore to scrap in steel plant feed on a global basis.

Jan 1, 1992

By T. A. Johnson

Recovering from low demand in 1975, raw mineral production in the United States maintained a steady climb in value and quantity throughout 1976, keeping pace with the gross national product (GNP), which increased 11.5% compared with that of 1975. The minerals industry, in the past, has met ever-increasing demand while keeping production costs to a minimum. To maintain this capability, technological research and development of more efficient processing methods must continue. The role of Government and its increasing involvement in minerals industry actions received unfavorable comment from various segments of the industry in 1976. Government pricing controls were of concern to most industrial firms marketing like products. Public land withdrawals in large blocks were of concern to the mineral industry.

Jan 1, 1978

By Donald P. Blasko

The Bureau of Mines investigated two areas of the Alaska Peninsula (Iniskin Peninsula and Becharof Lake) where oil and gas seeps were known to occur in an attempt to determine (1) whether the seeps are still active and (2) the amount of bitumen contained in the drainage leaving the seeps. The oil, water, oil-water, and gas were sampled and analyzed. Five oil samples were taken at four separate oil seeps. The API gravity of the oil ranged from 8.90 to 21.4° and the sulfur content was from 0.12 percent to 0.59 percent. Four of the seven gas samples obtained revealed fair high caloric values, ranging from 746 to 924 Btu/cu ft, and averaging 844 Btu/cu ft. A total of 44 water samples were obtained. Bitumen content of the water was as high as 9,773 mg/l at one seep, but averaged less than I mg/l where the seep-drainage water entered the Gulf of Alaska.

Jan 1, 1976

Part Two of this report is based upon six working memoranda prepared during the first half of 1972 at an early stage in our work for the Bureau of Mines. This work presents preliminary performance estimates of baseband voice and narrowband through-the-earth electromagnetic communications systems of principal interest to the Bureau for operational/ emergency mine communications applications. The calculations were prepared to obtain early indications of the feasibility and governing parameters of such communications systems. They are based on limited, but pertinent, coal mine electromagnetic noise data acquired to-date by Bureau of Mines contractors; on theoretical signal-attenuation characteristics for two transmitter antenna types of present interest to the Bureau and on semi-empirical models which describe the intelligibility of voice communications as a function of the frequency variations of the signal-to-noise ratio across the voiceband. This work examines the cases of baseband voice and narrowband communications for uplink and downlink transmissions, for frequencies up to 3kHz. Downlink transmissions are via a horizontal wire antenna, and uplink transmissions via a vertical-axis loop antenna, for typical mine depths of 300, 600, and 1000 feet. Representative coal-mine overburden conductivities of 10-2 mhos/meter (moderate and common) and 10-1 mhos/ meter (high) were used; the former figure for both voice and narrowband calculations and the latter for narrowband calculations only. Examples of high, moderate, and low, surface and subsurface, harmonic and broadband-impulsive noise conditions were taken from NBS and Westinghouse (WGL) mine noise data, together with examples of high- and low-levels of ELF atmospheric noise taken from M.I.T. Lincoln Laboratory data. The effects of simple voice spectrum shaping techniques on the intelligibility of through-the-earth voice communications are examined, and indexes of intelligibility more broadly based than signal-to-noise ratio are discussed. Finally, a means of overcoming the affects of 60 Hz noise and its harmonics which are the largest contributors to typical audio frequency in-mine noise, is suggested. These feasibility calculations are not intended to serve as definitive and complete treatments, but as a starting point: to establish first-order estimates of the magnitude and variability of transmitter power requirements under different noise, overburden conductivity, and mine depth conditions; to identify relationships, conditions, or frequencies that are likely to limit or enhance system performance; to reveal items requiring further investigation and data still required; and to suggest practical methods for optimizing system performance. These objectives were met by the calculations. Simple experiments to support these calculations can and should be carried out; together with more detailed investigations of specific modulation, coding, noise-suppression, voice-compression and signal-conditioning techniques, aimed at producing through-the-earth operational/emergency mine-communication systems that are not only effective, but practical and economically sound.

Jan 1, 1974

By George J. Conroy

This Bureau of Mines publication describes several fault locators and methods, including time domain reflectometers, a frequency domain reflectometer, tone generators, an infrared method, the Murray loop method, and high-voltage "click" methods. The Bureau of Mines has been conducting research into these methods for several years, to improve mine safety and facilitate production through rapid, safe location of trailing-cable faults. The problems encountered in practical applications are discussed, and schematic diagrams of several instruments fabricated by the Bureau are presented. Since no present single method of locating trailing-cable faults is universally applicable, a kit composed of several of the more promising fault locators is advisable.

Jan 1, 1978

By N. A. C. Smith

During the past, six, years, the Bureau of Mines has made and. published several hundred analyses of typical crude oils and 'has developed a system of interpreting the analyses and of classifying crudes. This system is presented here with. It is apparently equate for classifying crude oils into four main groups and has also been found very convenient in studying the geological relationships between crude oils, and the probable refinery yields of valuable products from them. Crude petroleum is morn to be a very complex substance. An analytical statement of its properties must, therefore, consist of two distinct parts, - first, the report of the results of the determinations made by the analyst in the laboratory, - second, the proper arrangement, classification and interpretation of these results so that the analysis, as a mole, will indicate the meaning- and the relative- importance of the essential characteristics of the oil.

Jan 1, 1927

By Raymond P. Maloney

The Rhyolite mercury prospect is on the south flank of Juninggulra Mountain--a large rhyolite intrusive in the Kuskokwim River region about 36 airline miles northwest of Red Devil, Alaska. Bulldozer trenching by the Bureau of Mines exposed bedrock at intervals in a 2,000-by 3,000-foot area where previous prospecting by the owners had disclosed abundant float and several in-place stringers containing cinnabar in widely varying amounts. The additional trenching indicated that the mercury mineralization in the limited area investigated was confined to erratically distributed short stringers and to small lenses, occurring in discontinuous zones in numerous silica-carbonate dikes and sills or along their altered contacts with sedimentary rocks. The geologic relationship of the mercury-bearing silica-carbonate dikes and the nearby rhyolite intrusive is similar to that existing at several other mercury mines and prospects in the. Kuskokwim region. The depth of over-burden and the presence of permafrost were serious obstacles to bulldozer trenching, and only a comparatively small part of the mineralized area was thus investigated.

Jan 1, 1962