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By Warren E. Morrison

Stimulated by 4 years of continuous economic growth without inflation, demand for energy in the United States reached an alltime high in 1964. Total value of production of goods and services (gross national product--GNP) for the year was $629 billion, an increase of 6.8 percent from 1963. Allowing for price changes based on 1958 dollars, the gain in real terms was 5 percent. In 1964 the Federal Reserve Board Index of Industrial Production stood at 132, a rise of 6.2 percent. With the impetus provided by personal income and corporate tax reductions during the year, aggregate wages, profits, and consumption reached record levels. Even the persistent balance of payments problem improved. Against this background the national consumption of commercial energy increased 4.2 percent. Energy needs continued to be met largely from domestic resources with imports, mainly crude petroleum and refined petroleum products, accounting for but 7 percent of the total. Mineral energy resources, namely gas, coal, and petroleum, contributed 96 percent of the input of energy into the economy during the year. The remaining 4 percent came from hydropower and nuclear power.

Jan 1, 1965

By F. W. Lee

This paper purposes to outline briefly results of seismic measurements made in the vicinity of blasts in a mine and in open-quarry operations. It endeavors to examine the amplitude and frequency of such vibrations as influenced by the loading, geology, and distance from the source and includes comments on factors that may index the destructiveness of a vibration and a method for measuring the stresses produced. There seems to be no simple mathematical analysis of the transmission of seismic energy through the ground, and experimental observations are at present most feasible. SEISMOLOGIC INSTRUMENTS Instruments developed by the Bureau of Mines for recording ground vibrations from quarry blasting comprise a new type of seismometer, oscillators, and a recording oscillograph. The seismometers respond to vibrations reaching them through the earth and transmit their characteristics by electric current to the oscilloglaph, where they are recorded by a beam of light on a moving strip of sensitized photographic paper. The seismometers are so constructed that their sensitivity to earth vibration can be controlled, thus keeping the amplitude of the recorded wave within bounds on the paper. Each instrument has been calibrated against vibrations of known intensity and frequency so that correction factors are known for the idiosyncracies of each unit. Moreover, each seismometer is calibrated in the field for its particular sensitivity setting at each blast. By these controls the actual movement of the earth due to vibrations of one ten-thousandth of an inch can be accurately measured.

Jan 1, 1936

By Sam S. Taylor

Subsurface disposal of oil-field brines was practiced in Oklahoma on a limited scale as early as 1925. The technique of subsurface injection has been improved immensely and has been applied with varying success in many oil-producing areas in Oklahoma, and elsewhere. This method of disposal, however, is only one of several methods available to operators of oil-producing properties, but, in contrast with usual methods of handling brines on the surface it eliminates the damaging effect of mineralized water on fresh-water supplies, vegetation, and aquatic and other animal life. Other methods of brine disposal approved by regulatory agencies in some States include (1) impounding in impervious ponds and solar evaporation, (2) controlled diversion into surface waters, and (3) recovery of the mineral salts of the brine. In most, States where oil is produced regulatory bodies authorize the use of one or more of these methods of brine disposal. In Oklahoma, for example, the Oklahoma Planning and Resources Board of the Conservation Commission has been authorized to adopt whatever methods or means may be necessary to prevent contamination by mineralization of all potable waters within the State.

Jan 1, 1942

By Sam S. Taylor

Subsurface disposal of oil-field brines was practiced in Oklahoma on a limited scale as early as 1925. The technique of subsurface injection has been improved immensely and has been applied with varying success in many oil-producing areas in Oklahoma, and elsewhere. This method of disposal, however, is only one of several methods available to operators of oil-producing properties, but, in contrast with usual methods of handling brines on the surface it eliminates the damaging effect of mineralized water on fresh-water supplies, vegetation, and aquatic and other animal life. Other methods of brine disposal approved by regulatory agencies in some States include (1) impounding in impervious ponds and solar evaporation, (2) controlled diversion into surface waters, and (3) recovery of the mineral salts of the brine. In most States where oil is produced regulatory bodies authorize the use of one or more of these methods of brine disposal. In Oklahoma, for example, the .Oklahoma Planning and Resources Board of the Conservation Commission has been authorized4/ to adopt whatever methods or means may be necessary to prevent contamination by mineralization of all potable waters within the State.

Jan 1, 1942

Presented in this volume are the basic mining techniques and production operations associated with underground bituminous coal mining. Chapter 2, "Multiflow Process Charts", presents, in sketch form, a description of the various operations characteristic of conventional and continuous mining. In order to focus attention upon the major components and operations in each work cycle, certain items are not shown in the sketches, e. g., machine electrical cables, brattice, and rib posts. The elapsed time shown for each sketch is considered representative for the various work elements summarized by the sketch. More detailed work element times can be found in Chapter 3, "Typical Work Cycle Times", and Chapter 4. "Standard Time Data".

Jan 1, 1971

By R. L. Guerguerian

Nowadays, most grinding mills driven by a wrap-around ring motor are operating successfully. Some of the earlier problems could be attributed to the lateral stiffness and stability of their bearings. As a result, modifications to the bearings included the rearrangement of the shoes, or the addition of more shoes, closer to the horizontal centerline. This technical paper reports a study of the effects of bearings on the lateral stiffness of grinding mills driven by a wrap-around ring motor. The discussions cover the design of the four shoe trunnion bearings and examine the effects of the angular location of the shoes.

Jan 1, 2000

Pillars in underground limestone mines are required to support the overburden and provide a safe, stable working environment for mining personnel and equipment. Pillar stability was assessed by the National Institute for Occupational Safety and Health in underground limestone mines in the Eastern and Midwestern United States. It was found that current mine layouts have been successful in providing support to the overburden, while a small number of isolated pillar failures were observed. The stable pillar layouts and failed pillars were plotted on a chart that demonstrates the relationship between pillar width-to-height ratio and pillar stress. The results show that pillar failures occurred at the lower range of width-to-height ratios and can occur at relatively low stress levels. Zones indicating the potential risk of pillar instability are shown on the chart, based on hazards associated with the onset of rib spalling, large angular discontinuities and unconfined pillars. The chart can assist limestone mine planners to evaluate potential instability in current or new pillar layouts that are similar to those included on the stability chart.

Jan 1, 2008

By Ruth F. Brinkley

This report is the 18th of a series of reports originally issued annually, and more recently bienially, to acquaint the public with the work of the Federal Bureau of Mines in explosives technology. Part I reviews briefly the overall activities during fiscal years 1957 and 1958.4/ Part II presents in abstract form the publications prepared by the Bureau that appeared during the period.5/

Jan 1, 1961

By Phillip R. Mulligan, Kevin Gantz, Aaron J. Ward, allen shirley, Sean Treadway

Understanding the impulse transferred into a structure by the coupled two-phase loading produced by an explosive charge buried in soil is of interest for various applications. The most common impulse measurement technique involves a buried explosive charge and a steel plate/test structure suspended above the charge. Upon detonation of the charge, the soil and overpressure heave the plate into the air. The plate’s trajectory and velocity provide the necessary information to calculate the total impulse transferred from the charge configuration.

Jan 1, 2016

By Gruenewaldt von

Paper presented at the IAGOD international symposium on mineralization related to mafic and ultramafic rocks held in Orleans, France, 1-3 September 1993. The principles of shear-driven aggregation of particulate matter suspended in fluids, a common industrial method of concentration and separation, were applied to a convecting magma to estimate the time required to sparge or strip the PGE and Cr content and concentrate it into the boundary layers. It was calculated that an ore-grade (e.g. 6 ppm PGE) boundary layer about 1 m thick would require 100 000 years at most to form from a body of magma 500 m deep with a PGE content of 20 ppb. Since concentration would be most vigorous when the magma was warmest, at least half of this concentration would take place in the first 10 000 years. The effect of dispersive pressure in the boundary layer would generate a concentration high of refractories just below the top of each boundary layer and another just above the bottom. If the magma was a double-diffusive system, it might evolve by the downward cascade of enriched boundary-layer material into the hotter, lower magma layers, where depending on saturation levels chromites would equilibrate and sulphides undergo partial or total resorption, enriching PGE levels in any remaining sulphides. This cascade process would in time greatly enrich the lower regions in PGE-bearing sulphides and chromites

Apr 1, 1994

By Lottrey A. L, Sowerby B. D, Cutmore N. G

On-line monitoring of low rank coal quality during input to a process has the potential to provide benefits through: ò anticipation of coal quality variations prior to utilisation; ò provision of a tool to help determine the influence of coal quality on process behaviour, and ò provide a direct measure of coal quality for pricing. Moisture and ash are the two most significant coal quality parameters for combustion. They determine the energy content which can be derived from the coal and the problems arising from the presence of ash in the process (eg ash fouling, corrosion, erosion, particulate emissions and ash disposal). Extensive pilot-scale testing and full-scale experience has shown that specific coal/ash constituents (eg Na2O/ash ratio, acid-soluble aluminium, silica, sulphur contents, etc) are also important for the behaviour of Latrobe Valley brown coal during combustion, ash formation, deposition and removal of ash in precipitators and furnace ash hoppers. This paper discusses the range of on-line analysis techniques which have been investigated and their application to low rank coal analysis. Preliminary results from a joint SECV/CSIRO project which aims to develop two separate advanced instrument systems are also presented. These systems are based on: ò microwave attenuation and phase shift - for direct determination of moisture content; and ò inelastic neutron scattering - to provide total hydrogen, carbon, chlorine and ash contents, with potential for calculation of moisture content, specific energy, sodium content and Na20/ash ratio using correlations.

Jan 1, 1992

By Brett Zernich, Michael Krulc, Brett Robinson

This paper provides an account of the efforts undertaken to construct the Northeast Interceptor Sewer (NEIS) project, which is a portion of a much larger program in Los Angeles, California to upgrade the city’s wastewater facilities. The project consisted of a number of elements, including both soft ground and rock slurry wall shafts, drilled shafts, soft ground EPBM mining, rock TBM mining, large diameter pipe placement, and underground structure construction. The need to complete the project under strict schedule constraints, in addition to the challenges of underground construction in congested urban areas, necessitated the work be undertaken with the proper balance of state of the art equipment, and thoughtful planning. The paper will detail the means, methods, and equipment used on the project, as well as discuss several of the unforeseen conditions encountered during construction.

Jan 1, 2005

By John V. Simmons, Peter J. Simpson

Excavated slopes in open pit coal mines are designed to be as steep as possible consistent with stability and safety requirements. Slope failures occur for many reasons, including oversteepening. This paper is concerned with slope design and excavation experience in the Bowen Basin coalfields of central Queensland (Figure 1), [ ]

Jan 1, 2006

By G. M. Zhao

The gasification of lump coke with CO2 was studied in a fixed-bed reactor. The effective diffusivity of the gas was evaluated from measurements of the reactivity of the lump coke, produced by BHP Steel in New South Wales, and from kinetic parameters that were determined from the reactivity of fine grains. The grain model of effective diffusion in porous media was adopted to express the gasification rate of the lump coke and was found to fit the experimental data well. The relationship between reactivity and textural characteristics of the coke was examined

Jun 18, 1905

By N. B. J. Kieser

Paper presented at the IAGOD international symposium on mineralization related to mafic and ultramafic rocks, held in Orleans, France, 1-3 September 1993. Platinum-group minerals (PGM) in the enriched zone at Dust Mountain occur in two separate parageneses, the first representing primary magmatic PGM and the second primary magmatic PGM that have been reduced to alloys during serpentinisation. Minerals in the first group were unaffected by hydrothermal alteration on account of their textural setting or stable chemical composition. Despite substantial alteration of the serpentinised assemblage, most evidence points to the dominant role of primary magmatic processes in determining PGM occurrence. Several base metals have nevertheless been introduced hydrothermally. With respect to surficial dispersion the single most important paragenetic factor was the reduction of sulphides to alloys, rendering them more susceptible to mechanical erosion and less so to chemical leaching. The different textural setting of Pd-group and Ir-group phases results in different dispersion characteristics, with major implications for stream sediment sampling

Apr 1, 1994

By D. Michael Holloway

The California Department of Transportation (CALTRANS) evaluated several pile foundation schemes for supporting the structures along the realignment of Interstate 880. The project replaces the double-decked (Cypress) viaduct collapsed in Oakland, California during the 1989 Loma Prieta Earthquake. Structural support demands led to the selection of steel pipe piles (16-, 24-, and 42-inch-(406-, 610- and 1067-mm-)diameter), filled with concrete and steel reinforcement. Deep penetrations required through layers of very dense/cemented sands in some locations, caused serious drivability and pile integrity concerns. The need for large pile driving hammers and large diameter steel pipe piles pushed the engineers well beyond local experience. Such questions as the feasibility of driving the pipes closed-ended through dense upper strata and quantifying the effects of installation on the long-term capacities of the piles led Caltrans to develop a comprehensive pile test program to address the design and construction issues effectively. The results were furnished to prospective bidders on the production stages of the ensuing contracts.

Jan 1, 1995

By Donald Bruce, Mark Harris, Wesley Schmutzler, James Sanders

"This paper evaluates the history, construction and most importantly the performance of two remedial seepage cutoff walls installed in two major dams in the United States. Beaver Dam, on the White River in northwest Arkansas, was completed in 1966 and seepage through the karstic limestone under the embankment was apparent almost immediately upon filling of the reservoir. Several attempts to stop the seepage by grouting were unsuccessful. In 1994 a cutoff wall consisting of secant piles drilled with 32"" diameter down-the-hole hammers to a maximum depth of 185'?was completed and the seepage was reduced to a negligible amount. It has been over 20 years since the completion of the cutoff wall, and all indications are that the cutoff wall is performing as expected. Walter F. George Lock and Dam on the Chattahoochee River near Fort Gaines, Georgia, was completed in 1963 and suffered the same problem as Beaver Dam due to the limestone on which the dam was founded. Cutoff walls were installed in both embankments (1980s) and solved the problem in these areas, but under-seepage at the concrete lock, dam and spillway structures increased to the point that remediation was essential. The cutoff wall had to be installed through 110'?of water and another 100'?into rock upstream of an active dam that continued to generate electricity during the construction of the cutoff wall. A secant pile wall, in combination with a diaphragm wall, was completed in front of these structures in 2004. It has been over 10 years since the completion this cutoff wall and, again, the cutoff wall is performing as expected. The paper describes the construction of these cutoffs, but focuses on the long-term performance in terms of controlling seepage and piezometric levels.BEAVER DAMBeaver Dam is located on the White River, 609 miles above its mouth, in Carroll County, Northwest Arkansas. The construction of the dam and Beaver Reservoir was authorized on September 1954 by the Congressional Flood Control Act for purposes of water supply, flood control and hydroelectric power generation. The dam site was selected in 1957: construction began in November 1960 and was completed in June 1966. (FIG. 1)"

Jan 1, 2017

By L. W. Vigrass

Porous and permeable rocks deeply buried in sedimentary basins contain immense volumes of hot water with the potential to supply low-grade heat energy. A part of Canada with sizeable potential for low-grade geothermal energy is the northern Williston Basin of southern Saskatchewan. In this region, the University of Regina has conducted a geological study investigating the feasibility of producing large quantities of warm water suitable for space heating in the Regina - Moose Jaw area. The study has shown that the most favourable geothermal reservoirs are in the Basal Clastic Unit (Cambrian Ordovician), which, at an approximate depth of 2,000 metres has predicted temperatures of 71°C to 74°C. We anticipate sustainable flow rates from these reservoirs of 100 to 300 ms/hr. The water contains about 150,000ppm of total dissolved solids, mostly sodium chloride. It is anticipated that the sulphate content will be 3,000 to 6,000 ppm, that the dissolved oxygen and hydrogen sulphide content will be small, and that the waters will be neutral to slightly alkaline. It is anticipated that the piezometric level will be 46 m below the ground surface for reservoirs in the upper part of the Basal Clastic Unit and 141m below the ground surface for the lower reservoirs of the unit. Plans are to build a low-grade geothermal research, testing and demonstration facility at the University of Regina. To be a practical demonstration, the facility will have to handle very large volumes of water. Because of high salinity, the water will be re injected into a subsurface reservoir. We do not anticipate insurmountable problems because of salinities or as a result of corrosion provided that the waters are not aerated during handling

Jan 1, 1979

By F. D. Richardson

STAFF: Editor, Gerhard Derge Carnegie lnstitute of Technology Schenley Park Pittsburgh, Pa. 15213 Editorial Assistant, M. A. Redmerski Production Editor, Otto T. Johnson THE METALLURGICAL SOCIETY: Jack H. Scoff, President; Richard C. Cole, Past-President; Harold 0. Emerick, President-Elect; Ralph L. Hennebach, Treasurer; Robert W. Shearman, Secretary; Donald A. Parks, Assistant Secretary; Leslie S. Wilcoxson, Assistant Secretary. PUBLICATIONS COMMITTEE OF THE METALLURGICAL SOCIETY: R. E. Lund, Chairman; T. E. Dancy, H. O. Emerick, P. R. Gouwens, R. E. Grace, J. H. Jackson, H. H. Johnson, A. E. Lee, Jr., R. R. Nosh, R. D. Pehlke, and Paul Queneau. Review and selection of manuscripts is under the supervision of the following Publications Committees: Extroctive Metallurgy Division: R. E. Grace, Choirmon; G. M. Bell, D. W. Bridges, J. M. Cigon, G. W. Heoly, T. A. Henrie, R. D. (Holli-doy, C. E. O'Neill, C. S. Somis, A. W. Schlech-ten, and Charles Shull. Iron and Steel Division: R. D. Pehlke, Choirmon; T. P. Floridis, Arnulf Muon, G. R. St. Pierre, E. T. Turkdogan, L. H.Von Vlock, and J. M. Uys. lnstitute of Metals Division: H. H. Johnson, Jr., Chairman; J. B. Clark, Vice Choirmon; M. R. Achter, G. F. Bolling. J. O. Brittoin, G. P. Conard, II, R. S. Davis, L. A. Girifolco, G. T. Hohn, J. P. Hirth, L. Himmel, G.T.horn, George Krauss, J. D. Livingston, R. D. Manning, H. M. Otte, S. V. Rodcliffe, R. E. Reed-Hill, H. C. Rogers, E. ScaIa, O. Sherby, M. T. Simnad, G. R. Speich, E. A. Steigerwald, R. A. Swolin, W. A. Tiller, W. R. Upthegrove, J. B. Wagner, Jr., Derek Wolton, H. W. Weart, W. W. Webb, and D. Published seven times yearly in February, March, April, June, August, October, and December by the American lnstitute of Mining, Metallurgical, and Petroleum Engineers, Inc., 345 East 47th Street New York, N. Y. 10017. Telephone PLAZA 2 -6800. Subscription $30 per year for non-AtME members m United States and North, South, and Central America; $32, foreign; $7.50 for AlME members Single copies, $6.00, single copier foreign, $6.50. The AiME is not responsible for any statement made or opinion expressed in its publications . . . Copyright 1964 by the American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc. . . . Registered cable address, AiME New York Indexed in Engineering Index, Industrial Arts Index, and Chemical Abstracts. Second dost postaas poid ot New York, N. Y.,ond Ann Arbor, Mich. Volume 230, Number 6.

Jan 1, 1964

Two types of low-sulphidation epithermal mineralisation may be recognised in volcanic terranes. Chalcedonic Silica- Adularia-Illite type mineralisation is most common in rhyolitic terranes, whereas Crystalline Quartz-Illite-(Adularia- Kaolinite) type mineralisation is more typically formed in andesitic terranes. A third type of epithermal mineralisation, the high sulphidation or Vuggy Silica-Alunite- Kaolinite-Illite type, is also common in andesitic terranes. Episodic violent boiling, accompanying hydraulic fracturing and hydrothermal eruptions, characteristic of geothermal systems in rhyolitic terranes, is stressed for the formation of Chalcedonic Silica mineralisation. Such boiling of deeply circulating meteoric groundwater, with some magmatic fluid contribution, provides chalcedonic veining, episodic banding and brecciation textures, adularia stability, bladed calcite, and extreme loss of H2S from the fluid to cause major gold deposition. Crystalline Quartz mineralisation is probably caused by the mixing of shallow acidic groundwater with ascending deep geothermal fluids beneath andesitic strato- volcanoes. The cooling effect, oxidation, and increased acidity, overcomes the dilution effect, and results in quartz deposition, illite (and locally kaolinite) alteration, and precipitation of metals. Extensive formation of base-metal sulphides further enhances gold deposition. Violent boiling is restricted to local structural dilation sites, potentially producing high grade "bonanza" gold mineralisation.

Jan 1, 1991