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By R. S. Warfield

Several reconnaissance-type surface and drill core samples of Arctic Northwestern Alaska coals were taken during the summer field seasons of 1964 and 1966 for coking studies. Surface samples were taken from the Kokolik River and the Cape Beaufort areas; core samples were obtained from the Kukpowruk River and the Cape Beaufort areas. Only one Kokolik River surface sample possessed coking properties. This sample, representing an 11.6-ft coal seam, made coke approaching metallurgical quality when a 30-pct portion of selected blending coals was added. Four Kukpowruk River core samples, each representing the same 19-to 20-ft coal seam, were all of about the same coking quality. No differences of coke quality attributable to depth of permanently frozen overburden were found, but the data confirm previously reported information that the 19- to 20-ft coal bed is a potentially satisfactory base coking coal. In the Cape Beaufort area, a core sample with appreciable coking properties was taken at depth from a coalbed determined noncoking in a surface sample.

Jan 1, 1969

By James W. Myers

"Packaged fuel" is the trade name applied by the industry to a product consisting of coal screenings and a binder compressed into 3 -or 4-inch cubes and wrapped (six or eight in a package) in sturdy paper and sealed with gummed tape. Parry describes the product in greater detail and distinguishes clearly between packaged fuel and briquettes. The industry developed from the desire of retail coal dealers to improve utilization of the relatively large quantities of slack sizes that result from the degradation, during shipping and handling in the yard, of friable coal, particularly Pocahontas coal. During the war an attempt was made to apply this technique to anthracite fines, and a recent publication of the U. S. Bureau of Mines reported the results of physical and combustion tests on packaged fuels containing anthracite fines. References made in this report to the previous investigation on packaged fuels containing anthracite represent data or conclusions presented in Report of Investigations 3882. This investigation was conducted as a continuation of the previously reported studies and consisted of physical and combustion tests of packaged fuels made from high-volatile bituminous coal, as well as the low-volatile bituminous coal ordinarily used in the industry, to determine their relative suitability for domestic firing. Particular attention was given to the smoke-producing properties of the packaged fuels because of the increasing importance of the prevention or reduction of smoke from hand-fired domestic heating plants resulting from the widespread enactment of smoke-prevention ordinances.

Jan 1, 1951

By E. D. Calvert

Molybdenum has been successfully cast into static and rotating molds in conventional equipment used for casting titanium and zirconium. Melting was accomplished by using an arc potential of 36 to 40 volts with a current of 10,000 amperes. Pouring efficiency, after a skull had been formed in the crucible, averaged 70 percent. Techniques are described by which four successful castings were made. Tensile properties on specimens cut from one centrifugally cast tube averaged: Tensile strength, 39,800 p.s.i.; yield strength (0.1 pct. offset), 35,300 p.s.i.; elongation, nil; reduction in area, nil; impact strength, 2 ft.-lb.; hardness DPH (diamond pyramid hardness) 180. Mold reaction was not evident in shapes cast in machined graphite. This was not true, however, for rammed graphitic-base molds.

Jan 1, 1960

By W. G. Pariseau

This Bureau of Mines report is an evaluation of the state of knowledge about gravity flow from bin hoppers, the most commonly used method of handling bulk materials where the force of gravity is used. The requirements for flow to be initiated and to continue, formulas developed experimentally or mathematically from various assumptions to describe the materials flow, and the question of whether or not a material will flow over the entire cross sectional area of the bin hopper according to the flow regime developed are the primary areas discussed. The work of A. W. Jenike, whose pioneering investigations raised bin hop- per design from the trial and error state, is examined in depth and its limitations and assumptions are pointed out. Bin hopper design depends heavily upon prior experience, and suggestions for further studies of bin hopper flow to include the effects of feeders are made.

Jan 1, 1972

By B. W. Gandrud

This report, consisting mostly of float-and-sink data and washability curves, has been prepared in connection with an exhaustive study of coal preparation in Alabama conducted, by the U, S. Bureau of Mines and the University of Alabama with the cooperation of the different coal operators On the basis of the float-and-sink data, an attempt has been made to determine approximately the extent of ash and sulphur reduction obtainable under given conditions on coal from the mines which were sampled, In the coal-producing districts of Alabama a great deaf of attention has been given in recent years to the problem of improving preparation methods so as to obtain from various coal beds the best possible grade of washed coal. This is especially so where the washed coal is used for the making of metallurgical coke in by-product plants or where there are possibilities of using the coal for this purpose. In the manufacture of metallurgical coke, the sulphur content of the coal is a very important consideration. It is quite often the determining factor as to whether or not a certain coal can be used for coke making. In the studies which form the basis for this report, all samples have been analyzed for sulphur in order to obtain information regarding the possibilities of sulphur elimination as well as ash reduction, and the samples on which reports are made were obtained from beds that are characterized by rather high percentages of sulphur. In connection with the present investigations of coal preparation in Alabama a standardized method of interpreting float-and-sink data has been used extensively for predicting the ash and sulphur reduction and yields obtainable in a commercial washing plant from various sizes of raw coal and from the raw coal as a whole after a certain degree of crushing. This method, which will be explained in subsequent chapters, was used in interpreting the data contained in this report. The samples used for these washability studies were obtained from the following mines in the Warrior field of Alabama: Beltona mine on the Jefferson bed; Dolomite and Mulga mines on the Pratt bed; Coal Valley No. 163 and Coal Valley No. 11 mines on the Corona bed; Cedar Cove mine on the Carter bed.

Jan 1, 1932

By B. W. Candrud

This report, consisting mostly of float-and-sink data and washability curves, has been prepared in connection with an exhaustive study of coal preparation in Alabama conducted by the U. S. Bureau of Mines and the University of Alabama with the cooperation of the different coal operators on the basis of the float-and-sink data, an attempt has been made to deter-mine approximately the extent of ash and sulphur reduction obtainable under given conditions on coal from the mines which were sampled. In the coal-producing districts of Alabama a great deal of attention has been given in recent years to the problem of improving preparation methods so as to obtain from various coal beds the best possible grade of washed coal. This is especially so where the washed coal is used for the making of metallurgical coke in by-product plants or where there are possibilities of using the coal for this purpose. In the manufacture of metallurgical coke, the sulphur content of the coal is a very important consideration. It is quite often the determining factor as to whether or not a certain coal can be used for coke making. In the studies which form the basis for this report, all samples have been analyzed for sulphur in order to obtain information regarding the possibilities of sulphur elimination as well as ash reduction, and the samples on which reports are made were obtained from beds that are characterized by rather high percentages of sulphur. In connection with the present investigations of coal preparation in Alabama a standardized method of interpreting float-and-sink data has been used extensively for predicting the ash and sulphur reduction and yields obtainable in a commercial washing plant from various sizes of raw coal and from the raw coal as a whole after a certain degree of crushing. This method, which will be explained in subsequent chapters, was used in interpreting the data contained in this report. The samples used for these washability studies were obtained from the following mines in the Warrior field of Alabama: Beltona mine on the Jefferson bed; Dolomite and Mulga mines on the Pratt bed; Coal Valley No. 16B and Coal Valley No. 11 mines on the Corona bed; Cedar Cove mine on the Carter bed.

Jan 1, 1932

By R. A. Strehlow

This is the final report for U.S. Bureau of Mines contract HO-122122, which was in effect from June 30, 1972 through January 4, 1976. The work resulted in the design and construction of a large laboratory scale coal dust burner and the use of this burner to study gaseous and coal dust flammability. A new technique for determining gas phase flammability was developed and the effect of solid and gaseous suppressants on the propagation of coal dust flames was studied. In addition, a technique for measuring the C/H ratio in the flame was developed and the C/H ratio that was measured in a coal dust flame on this burner showed that the burning process was preceeded by pyroysis of the coal dust. Both experimental and theoretical studies showed that radiative trans-port is very important to the propagation of a coal dust flame.

Jan 1, 1977

By G. W. Jones

In a previous report,6/ results were given that showed the amount of natural ventilation in a manhole having a capacity of 74.1 cubic feet when the number of ventilation openings in the cover was varied from no openings to a maximum of 48. The result s showed that the ventilation (air changes per day) in the manhole was proportional to the area of the openings in the cover, and also that the number or area of the openings was the factor that chiefly affected the ventilation.

Jan 1, 1937

By L. R. Stark

Two wetland simulation experiments were carried out in order to determine the effects on manganese retention of several wetland design parameters, including flow rate, inlet pH, carbon supplementation, substrate type, and surface free water depth. The primary aim in each experiment was to determine if sustained manganese retention could be accomplished under the specific experimental treatments. If successful, these experiments could recommend design parameters for the construction of field wetland systems for manganese treatment. Crushed limestone clearly was superior to spent mushroom compost with respect to manganese retention. The presence of free surface water detracted from manganese treatment, while lower flow rates enhanced manganese treatment. Sustained manganese retention was achieved using crushed limestone as the substrate coupled with an absence of surface free water, under inlet water conditions of pH 7.0 and no appreciable iron. Sustained manganese retention was not achieved under reducing conditions using spent mushroom compost while varying flow rate, inlet pH, and carbon supplementation regimes. However, lowering the flow rate resulted in many significant beneficial effects on outlet water chemistry: lower outlet manganese concentrations (over the short term), higher outlet pH, lower outlet acidity, higher outlet alkalinity, higher outlet sulfide, lower outlet sulfate, and lower outlet redox potential. Supplementation of the wetlands with dairy whey resulted in lower outlet manganese concentrations (over the short term), marginally higher outlet sulfide levels, and acted to lower the redox potential under the high flow regime. Wetlands receiving a neutral pH had lower outlet acidity, higher outlet alkalinity, lower outlet sulfate, but equivalent outlet manganese concentrations than wetlands receiving an acidic pH. When manganese is the primary mine water contaminant and a passive water treatment system is to be used, it is recommended that crushed limestone with negligible surface water be used in place of composted materials. This recommendation assumes a source water with circumneutral pH and an absence of other metals.

Jan 1, 1993

These proceedings consist of an introduction and four descriptive papers. The first paper is an update on fire protection for large haulage vehicles, the second paper is concerned with improved visibility systems for large haul- age vehicles, the third paper is on improved ladders for large haulage vehicles, and the fourth paper is concerned with large haul-age vehicle operator training systems.

Jan 1, 1980

By David A. Summers

The use of high pressure fluid cavitation is investigated as a means of breaking an ore into its constituent grains. This Cavitational Rock Dissagregation (CRD) is found to be possible and effective in breaking down galena ore, both in sandstone and dolomite host material. The technique did not work as well in comminuting and cleaning oil shale, because the cavitation drove the oil into emulsion with the water. The presence of dominant bedding in the rock also caused preferential breakage to these lines, rather than to the individual grain boundaries. This problem was also encountered in tests on igneous ore where weakness plants of the overall ore proved weaker than the boundaries of the individual grains. It was found that the prevailing expression of cavitation erosion dependence on pressure was not absolutely valid. In contrast it was found that CRD is much more sensitive to jet flow diameter, and when this was recognized it was found possible to erode rock with compressive strength of up to 350 MPa with operating jet pressures of 10 MPa.

Jan 1, 1982

By M. C. Irani

The Bureau of Mines, in cooperation with the Mine Safety Appliances Co., has developed a continuous-recording methanometer utilizing a catalytic combustion detector. The methanometer, which is presently operating at 22 exhaust fans at 14 mines in the Eastern coalfields, is reliable and simple to install, operate, and maintain. The instrument and the details of its installation and calibration are described. Analytical data obtained by infrared spectrophotometer and gas chromatograph are presented to substantiate its re liability.

Jan 1, 1974

By A. L. Service

Idaho has nearly 6 billion tons of potential sources of phosphorite, 10 to 31 percent P2O5' above and within 100 feet below entry level, the largest potential of any State in the United States. In 1963 Idaho ranked third after Florida and Tennessee in total mine and marketable production of phosphate rock; Montana ranked fourth. This report describes phosphate deposits, mines, and prospects in 10 districts covering most of the Idaho phosphate field. All mine production of phosphate rock in Idaho comes from surface mines and is processed to phosphate fertilizers, phosphoric acid, and elemental phosphorus. Producing districts are Fort Hall (Gay mine), Trail Creek (Conda and Ballard mines), and Crow Creek (Georgetown Canyon mine). FMC Corp. and J. R. Simplot Co. at Pocatello have the largest elemental phosphorus and fertilizer production facilities, respectively, in the State, followed by Monsanto Co. and El Paso Natural Gas Products Co. (formerly Central Farmers Fertilizer Co.). The only other major phosphate processing plant in the State is the phosphoric acid and phosphate fertilizer complex at Kellogg operated by the Bunker Hill Co. In 1963 a plant was constructed and put on line at Monsanto, Idaho, to recover vanadium from ferrophosphorus produced by electric furnace operations in the area. El Paso Natural Gas Products Co. completed construction of a fertilizer and phosphoric acid plant near Conda in 1965. There is a small fertilizer plant producing phosphate fertilizers for local consumption in Soda Springs.

Jan 1, 1966

By L. C. George

The Bureau of Mines measured vapor pressures of selected mixtures in the binary system SnCla-ZnC12 by the static pressure method. Equations expressing the vapor pressure) and the heat and free energy of vaporization) as functions of temperature were developed by numerical analysis based on the sigma-plot method. It was found that the vapor pressure of any SnCl2-ZnCl2 mixture) at any temperature within the range of this investigation) could be accurately calculated from the derived values for the heat and free energy of vaporization for the mixture, with a probable error of 0.01 cm Hg or less.

Jan 1, 1967

By Charles Vaught, Kathleen M. Kowalski

Safety and health professionals from all sectors of industry recognize that training is a critical element of an effective safety and health program. A major concern in the mining industry is how to train both an aging workforce and the expected influx of new miners and mine managers as older workers retire. Thus, a review of some of the basic principles of adult learning may be helpful to mine trainers. This paper discusses the principles of adult learning based on research in education and psychology. It stresses the importance of taking a systems approach to training, focusing on the relationship between the environment and technology, and understanding how workers interact with both. The authors argue that the principles of adult learning and a systems approach are fundamental to the delivery of effective training in the mining industry. Examples of training programs developed by the Pittsburgh Research Laboratory of the National Institute for Occupational Safety and Health are presented within two broad performance domains: routine and nonroutine skills. Basics of curriculum development are also briefly presented to provide the mine trainer with a template for program development.

Jan 1, 2002

By Francis E. Federspiel

In 1984 and 1985, at the request of the U.S. Forest Service, the U.S. Bureau of Mines examined the 87,720-acre South Boise Yuba study area (formerly known as RARE II Wilderness Recommended area I-4553) to evaluate mineral resources. The study area and additions are in Blaine, Camas, and Elmore Counties, 10, about 60 mi east of Boise. Granitic rocks of the Cretaceous age Idaho Batholith occupy the western two-thirds of the study area. A Tertiary age granitic complex has intruded, and broken into small blocks, Paleozoic age sedimentary rocks in the eastern third of the study area. Tertiary Challis Volcanics overlie both of these rock types. Principal mineralized structures are gold-and silver-bearing quartz veins and shear zones trending northwest to easterly in the Cretaceous granitic rocks. Copper, lead, and zinc are accessory metals in many mineralized structures.

Jan 1, 1987

By Louis Schaffer

A literature review concerning dredging hazards and dredge safety practices and an examination of MSHA accident and injury statistics on dredge mining in the United States provided the background for an analysis which was completed by visiting 31 dredge operations, dredge manufacturers, and dredging experts. The principal hazards are discussed and countermeasures are suggested in several areas. Drowning is the single largest fatal injury category. Special emphasis is given to the design, care and use requirements of personal flotation devices.

Jan 1, 1984

By Kenneth H. Johnston

This report describes in detail three waterflooding projects and a pressure-maintenance project in Butler and Cowley Counties, Kans., that will be visited on the 1963 annual spring tour of the Kansas-Oklahoma Waterflood Association. Among the unique features of the projects are the flooding of five oil-producing horizons separately with injection water furnished by two water-treating plants. Discussion of the individual projects includes information on their early history, the source and treatment of the injection fluids, oil production decline curves, and the results of water injection on oil production.

Jan 1, 1963

By P. C. McWilliams

Theoreticians in soil mechanics have been pursuing a probabilistic approach to the factor of safety of an embankment or darn for the past 10 years. The motivation for this work is in contrast to the current practice of deterministically computing a factor of safety and treating it as an absolute with no regard to its inherent statistical variability. Basic to the probabilistic approach is the selection of an appropriate statistical model to represent the histogram or probability density function (PDF) of the factor of safety values, Rather than simply assuming which PDF is appropriate, the Bureau of Mines collected data at two waste disposal embankments for consideration, This report addresses three candidate models, using the techniques of nonlinear curve fitting, and identifies the "best" model. A propagation of error formula for estimating the variability of Fellenius? factor of safety is also discussed.

Jan 1, 1983

By A. George Stern

The literature dealing with the drilling of oil wells has become extensive during the last few years, and oil men can find much information relating to drilling muds in the technical literature of the petroleum industry. Although large tonnages of clay are used in preparing drilling mud (also known as drilling fluid), almost no information has been published to apprise the clay industry of the types of minerals used, with their requirements and limitations. It is from this point of view that the present report has been prepared.

Jan 1, 1941