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By Ronald J. Mathis

The objective of this contract is to design, build, surface test, and evaluate a breadboard prototype of the Variable Wall Mining System so that data are available for the design of a production machine. The Variable Wall Mining System (VWMS) consists of a series of side cutting augers, connected end to end, and distributed across a panel. Supplying rotary power at the end of the string and anchorage from conventional longwall roof supports, the augers are sequentially thrust into the face and then lifted to the roof to extract the coal in a continuous manner. The augers not only cut but also transport the coal. The effort described in this report summarizes the operation characteristics of the VWMS, the design methodology used to develop various working models, the surface testing of a ½ -scale version of the VWMS, prediction of power requirements and performance potential of a full-scale system, and a critique of the VWMS concept, conclusions, and recommendations.

Jan 1, 1987

By A. Gene Collins

Potassium, lithium, strontium, barium, and manganese are present in many oilfield brines, None of them except barium is determined routinely in brine analyses. Therefore, sensitive and accurate flame-spectrophotometric methods were developed. Potassium, lithium, and strontium were determined by a standard-addition technique in ethyl alcohol solutions. Barium and manganese were determined in ethyl alcohol and normal propyl solutions, respectively, after interfering substances were removed.

Jan 1, 1962

By Cecil Q. Cupps

Results are presented of a comprehensive study of the characteristics of the original oil in the Weber sandstone reservoir, Rangely oil field, Colorado. Through the medium of subsurface sampling, adequately representative samples of the original reservoir oil were obtained from many parts of the reservoir over a period of 5 years concurrent with active development of the reservoir. Data of differential gas liberation, pressure-viscosity, and. pressure-volume-temperature relationships are shown for 12 subsurface oil samples. Data also are given of reservoir pressure and. temperature, composition of liberated or solution Gas, composition of 22 produced-gas samples, and Hempel analyses of crude-oil samples from 18 wells. The characteristics or physical properties of the 12 subsurface oil samples, as determined by laboratory analyses, were correlated with elevation of the top of the Weber sandstone. These relationships of oil characteristics to elevation in the reservoir show that only the oil in contact with the initial gas cap was gas-saturated at the existing pressure and temperature. The characteristics of the original reservoir oil were marked by an appreciable decrease of saturation pressure and solution gas-oil ratio and increase of viscosity and density with depth below the gas-oil contact. The composition of solution gas and of' produced was also was found to vary with elevation of the oil in the reservoir.

Jan 1, 1951

By M. K. McCarter

Previous investigations suggest the possibility of determining shear strength of geologic materials by measuring the force necessary to rupture the web between two closely-spaced, parallel holes using a borehole jack. Current research using finite element modeling and laboratory testing of intact rock indicates that web failure initiates by tensile fracturing induced by a complex stress field. Based on these results, a theoretical justification for relating web strength with shear strength appears unlikely for holes of equal diameter spaced two diameters apart. Empirical results, however, show a strong correlation between average web strength and average unconfined compressive strength for some rock materials under laboratory conditions. A good correlation also exists between residual web strength and the residual angle of friction under the same conditions. This research project involves the construction and field testing of a large borehole jack. The jack is designed to operate within a conventional 12-1/4 inch rotary blasthole common to open pit mining. The system is capable of exerting approximately 800,000 pounds on curved platen measuring roughly 4x24 inches. Field tests indicate that the system will operate in a mining environment, and preliminary results suggest the possibility of using the force-displacement data generated by the jack to rank the competency of material within a mine bench.

Jan 1, 1982

By Donald F. Reed

In its program of investigation of deposits of strategic minerals, the Bureau of Mines did some development drilling from October 1247 to March 1948 at the Pickering Creek deposits, Charter County, Pa., in an endeavor to find an additional source of supply of lead and zinc. Lead mining in Pickering Creek Valley showed great activity from 1851 to 1855; but after this period mining gradually declined until 1870 when all mines were. One small mine did some work from 1917 to 1920. The ores were sulfides of lead and zinc, which were partly oxidized from the surface to the 20-foot level. As zinc was penalized at the reduction works, the ore was sorted at the mine and the zinc discarded. The Wheatley and Chester County veins contained the beet ore bodies in the district. These converging veins are 2 to 5 feet wide. To cut the veins below the old mine working' the Bureau of Mines diamond-drilled eight holes aggregating 2,820 feet. No significant lead-zinc mineralization was found.

Jan 1, 1949

By Lon A. Williams

This appendix contains drawing lists and drawings of components and assemblies designed for the prototype portable and machine mounted lighting systems per Tasks II & IV of Contract No. H0220065.

Jan 1, 1976

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 J. P. Morris

The Bureau of Mines investigated the mechanics of fuming of iron-carbon melts during top-blowing with oxygen. Melts weighing 45 lb were prepared in an induction furnace and blown with oxygen by means of water-cooled lances. The rate of fuming was measured and correlated with the operating variables. The data showed that the primary cause of fuming was a boil at the bath surface in the impingement zone of the oxygen jet. Nucleation of the carbon monoxide bubbles producing the boil was apparently brought about by the precipitation of an oxide phase. The actual fuming mechanism involved partial oxidation and vaporization of bubble films and fine metal spray generated by the bursting of the bubbles. Bubbles that formed outside the impingement zone produced little fume. The distribution of trace elements between the metal and fume strongly indicated that the fume contained fine spray particles as well as particles that had condensed from vapor. The rate of fuming was found to be proportional to the carbon content of the metal) the concentration of oxygen in the jet) and the bath temperature) provided that a continuous boil occurred. In the absence of a boil) very little fume was produced.

Jan 1, 1967

By V. F. Parry

The major industrial uses of char or semicoke produced by low-temperature carbonization of coal4/ are as fuel for generating electric power, for blending with metallurgical coking coal as a substitute for low-volatile coals, and for gasification to produce synthesis gas for chemical purposes. This paper discusses various methods for carbonizing coal, emphasizing processing of the noncoking coals to produce char for thermal power-plant fuel and for blending with metallurgical coking coals and tar for chemical use. Low-temperature carbonization is a relatively simple processing step involving heating coal to about 900° to 1,200° F. to decompose the coal into 4 main products: (1) Semicoke or char; (2) complex, partly oxygenated liquid hydrocarbons or tar; (3) fixed gases; and (4) water. If the coal is heated rapidly under conditions that prevent decomposition of the primary products, 68 to 87 percent of the net heat in the raw coal is left in the char and 10 to 23 percent of the potential heat appears in the primary tar. Fixed gases represent approximately 7 percent of the heat and approximately 2 percent is lost or dissipated in the reactions of decomposition. Considering the different ranks of coal in the United States, the yield of tar will vary from about 9 to 44 gallons per ton, therefore it is important that each coal be carefully considered if it is to be carbonized for industrial use.

Jan 1, 1955

By L. A. Stewart

This paper describes all occurrences of barite in Arizona that were known or reported to the authors. The history, ownership, production, and geologic setting are discussed for most of the deposits. The uses and specifications of product grades are briefly discussed. Seventy-five deposits were examined in 9 of the 14 counties of the State. The descriptions are given under county headings. No occurrences were reported in the four northeastern counties of Coconino, Navajo, Apache, and Greenlee, nor in Santa Cruz in the southern part of the State. From about half of the deposits examined, 55 samples were taken; of these, 45 were for chemical analysis, and 8 larger samples, ranging from 100 to 350 pounds, for beneficiation tests. A 30-ton bulk sample was taken for pilot-plant tests. Bench-scale flotation tests of the eight samples employing several different procedures and reagent combinations yielded marketable-grade barite products with barite recoveries ranging from 60 to 97 percent. Five of the samples contained enough fluorspar to warrant its recovery. Acid-grade concentrates, which accounted for fluorspar recoveries of 45 to 70 percent, were obtained from three of these ores. Batch laboratory tests of a representative portion of the 30-ton bulk sample revealed that acid-grade fluorspar and high-grade barite concentrates could be recovered. Results of the laboratory and continuous pilot-plant tests of this ore will be presented in a separate report.

Jan 1, 1960

By A. R. Taylor

In recent years, thermodynamic data have been used to a greater degree than ever by the chemical and metallurgical engineer as a means of predicting and controlling chemical reactions. To satisfy the spiraling demand for basic physical data needed for the calculations, the Bureau of Mines is studying the heat capacities of a variety of chemical compounds at high and low temperatures. This paper is one of a series presenting such data. The heat capacities of two alkaline earth compounds, strontium bromide and strontium nitrate, were measured in a temperature range of 60° to 300° K. in an adiabatic calorimeter and at temperatures of 300° to about 1,200° K. in a Bunsen ice calorimeter. The construction and operation of the calorimeters are discussed in other reports.3 4 The heat-capacity data presented in this report were extrapolated to 0° K., and smooth values of heat capacity, entropy, enthalpy function, and free-energy function were calculated and tabulated at even 10-degree intervals. The enthalpy data were fitted with algebraic equations by applying the method of least squares; calculations a£ heat-capacity values, entropy, enthalpy function, and free-energy function were made at even 50-degree intervals. The heat and entropy of fusion of strontium bromide were calculated from the enthalpy measurements.

Jan 1, 1962

By William R. Wayment, David E. Nicholson

The Bureau of Mines studied some physical properties of hydraulic backfills and their paramount characteristics , and made preliminary attempts to compact this type of material . The in- place density of hydraulic backfills affects the properties of strength , consolidation , and water percolation . Dense fills give better support than loose fills . In - place density properties themselves are affected by grain size , grain size distribution , and the particular conditions of sedimentation in a stope ( the amount of work the slurry water does to compact the material ) . Field sampling of in - place densities of fills presently used in four different mines and laboratory and underground compaction tests using a standard concrete vibrator show that the initial in - place density of the cohesionless fill material tested can be significantly increased by vibratory compaction .

Jan 1, 1964

Two coal seams were selected and the conceptual designs were based on the geological and physical conditions typical of these seams. As a result of the screening process presented below, the two coal seams selected were the Lower Kittanning Seam in central Cambria County, Pennsylvania and the Pittsburgh Seam in northwestern West Virginia and southwestern Pennsylvania. SELECTION PROCESS FIRST SCREENING OF LONGWALL OPERATIONS The list of longwall operations prepared in Phase I and included in the Phase I report, was used as the basis for a first screening. From this list it was determined which longwall operations were not in the Appalachian coal fields and not in a coal seam of the thickness range of 42 to 72 inches. The first screening eliminated 30 of the listed operations, leaving 48.

Jan 1, 1976

By T. H. Jeffers

The U.S. Bureau of Mines has developed porous beads containing immobilized biological materials for removing metal contaminants from waste waters. The beads, designated as BID-FIX beads, are prepared by blending biomass, such as sphagnum peat moss or algae, into a polymer solution and spraying the mixture into water. Laboratory studies were conducted to determine bead sorption and elution characteristics. Batch and continuous tests demonstrated that BIO-FIX beads sorbed arsenic, cadmium, lead, and other toxic metals from acid mine drainage waters collected from several sites. Selectivity for heavy and toxic metal ions over calcium and magnesium was demonstrated. The beads exhibited excellent metal sorption and handling characteristics in stirred tanks, column contactors, and a low-maintenance passive system. The sorption process was reversible, and metal ions were eluted from the beads using dilute mineral acids. Cyclic tests indicated that the beads continued to extract metal ions after repeated loading-elution cycles.

Jan 1, 1991

Commodities statistics and other information are available through the following three systems: Internet Access: To acccess the USBM Gopher server on Internet, connect to: gopher.usbm.gov port 70, using gopher client software. Or contact the Systems Administrator for technical questions: Matt Klevemann, 412-892-6499 (klevemmc@miner.usbm.gov) These USBM materials are available on Internet, with more to come in the future: Publications and other research findings, including this bimonthly publications list, newsletters, tech transfer updates, enviromental technology research, health and safety information. USBM software products Media materials and speeches. Mines Data: Computer bulletin board. Log on via modem through 202/501-0373, or call 202/501-0406 for technical assistance. Mines FaxBack: Return fax service. 1. Use the touch-tone handset attached to your fax machine's telephone jack. (ISDN [digital] telephones cannot be used with fax machines.) 2. Dial 202/219-3644. 3. Listen to the menu options and punch in the number of your selection, using the touch-tone telephone. 4. After completing your selection, press the start button on your fax machine.

Jan 1, 1995

By Carl W. Kelley

PRODUCTION in the United States of carbon black has increased from 20 million pounds per year in 1920 to over 2 billion pounds in 1964 valued at $156 million, mostly for consumption by the rubber-tire industry, which uses over 90 percent of total production. Production of over 2 billion pounds in 1964 is a 7.8-percent increase over 1963 and is the first time furnace black production has topped 2 billion pounds. Although 1964 channel black production dropped 6 percent below 1963, carbon black produced by the furnace process, which ac-counted for 92 percent of total production, increased 9 percent to 2,053 million pounds. Total shipments during 1964 amounted to 2,245 mil-lion pounds, a 7 percent increase. This growth parallels the expansion of the automotive and petroleum industries. Along with this expansion have been many advances, both in methods of manufacture and in the quality and variety of blacks available to industry. There are several kinds of carbon black, thermal, channel, furnace, lamp, and oil blacks. Until recently, channel has been the important black in rubber compounding. Following the introduction of the synthetic GR-S, and more recently of "cold rubber," it has been found that certain furnace blacks with particle size larger than that of the standard channel black give superior reinforcement. A great advantage of furnace black is that its yield per unit of gas feedstock is higher than that of channel black. The 184-million-pound increase in domestic carbon black sales was partially offset by a 37-million-pound decrease in exports. Decrease in exports especially to Europe, is expected to continue. In Europe, as in the United States, the major end use for carbon black is in the manufacture of automobile and truck tires. Although the number of automobiles in Europe is predicted to grow by about 7.5 percent per year, compounded until 1975, the increased demand will be met by a 20 percent increase in existing capacity and by the new plants being built in Europe by U.S. companies. Also) aromatic oils for producing furnace blacks are plentiful now that western Europe's chemical industry is switching to a petroleum base.

Jan 1, 1965

By L. D. Johnson

On a project which is to develop a system to suppress coal dust explosions, a facility has been built and several devices tested. The facility is a 317-foot, 4.5-foot diameter shock tube and to date 53 tests have been carried out with methane-air and methane/coal dust-air as the explosive mixtures. Suppression of slowly propagating (up to 300 ft/sec) flame fronts has been successfully carried out on two tests using the dry chemical extinguishing agent Purple K. Delivery of the material directly into the flame front Seems to be required if effective suppression is to be accomplished.

Jan 1, 1972

By W. K. Overbey

The Bureau of Mines conducted surface joint and stress measurements, airborne remote sensing imagery studies, compass-oriented borehole televiewer surveys, numerical simulation of fractured wells, and well productivity studies in a four-quadrangle study area of Ohio, to determine the effects of earth fracture systems on the deliverability of gas storage fields. The results of these studies indicate that much useful information about a gas storage reservoir can be obtained and put to practical use by studying--(1) oriented cores for fractures and directional permeability, (2) orientation of induced hydraulic fractures for alignment of well patterns, and (3) aerial photos and multispectral scanner imagery for general surface geology comparison and to determine if some, development patterns can be generated by such results. The absence of known tectonic elements associated with flat-lying sediments, such as faults or fracture zones that can be seen on the surface, indicates that the use of remote sensors such as radar or aerial photography is not likely to be useful in picking well locations for drilling. Studies similar to those discussed here should be conducted in gently folded and strongly folded sedimentary formation areas to determine if the increased knowledge of earth fracture systems under these conditions might be beneficial in gasfield and gas storage reservoir development.

Jan 1, 1974

By R. V. Ramani

One area of study in the Coal Mine Injury Analysis project was to illustrate and enhance the ability of mine safety management personnel to apply analytical techniques to injury experience data and to justify requests for funds for safety enhancement actions on a cost/benefit and other quantitative basis. Four volumes of this final project report detail (1) the objectives and scope of the mine safety management research, (2) the results of literature review, and case studies, and (3) models developed for mine safety management. The four volumes are titled as Volume III: Mine Safety Management, Volume IV: Analytical Techniques for Mine Safety Management; Volume V: Mine Safety Management Case Studies and Volume IX: Training Cost Model. In this volume, the quantitative procedures that have been developed for the mine-specific analyses of accident/injury experience data are presented and their applications are demonstrated in a summary form through case study examples. The quantitative procedures will aid mine safety management personnel to develop focused accident prevention strategies including training, as well as to justify the investment in such proactive programs through cost-benefit analyses.

Jan 1, 1993

By M. A. Hammer

In this study by the Federal Bureau of Mines Pennsylvania anthracite from the Eastern Middle field was oxidized by concentrated nitric acid at steam-bath temperature for 24 to 1,000 hours. The quantitative data obtained include yields of nitric-acid soluble and insoluble products and the distribution of carbon and ash in each. The acid-insoluble residues were examined for solubility in aqueous sodium hydroxide. With a sodium hydroxide concentration of at least 1 normal, a portion of the residue could be extracted in the form of a true solution. With lower alkali concentrations, peptization occurred. Alkali solubility of the residue increased with length of oxidation. However, when expressed in percentages of original coal weight, the alkali solubility remained essentially constant after 192 hours of oxidation. This suggests that the alkali-soluble products are converted to acid-soluble products at the same rate as the original coal substance is converted to alkali-soluble material. Microscopic observations of the peptization of the acid-insoluble residues revealed a gross micellar physical structure. The action of nitric acid is apparently not restricted to the surface of a coal particle. The acid penetrates the particle through the pore structure, dissolving some of the ash and altering the bonds between the coal micelles. The bond alteration, as indicated by ultimate analyses, involves the physical and chemical adsorption of the components of nitric acid. Some of the altered bonds are not thermally stable; this instability is shown by the complete loss of peptizing ability when the acid-insoluble products are heated above 200° C. This loss is accompanied by the evolution of water, oxides of nitrogen, and hydrocyanic acid.

Jan 1, 1961