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Radionuclides in plankton from the South Pacific Basin

Description: We have initiated an investigation of the utility of marine plankton as bioconcentrating samplers of low-level marine radioactivity in the southern hemisphere. A literature review has shown that both freshwater and marine plankton have trace element and radionuclide concentration factors (relative to water) of up to 10/sup 4/. We participated in Operations Deepfreeze 1981 and 1982, collecting a total of 48 plankton samples from the USCGC Glacier on its Antarctic cruises. Battelle Pacific Northwest Laboratories sampled air, water, rain, and fallout. We were able to measure concentrations in plankton of the naturally-occurring radionuclides /sup 7/Be, /sup 40/K, and the U and Th series, and we believe that we have detected low levels of /sup 144/Ce and /sup 95/Nb in seven samples ranging as far south as 68/sup 0/. Biological identification of the plankton suggests a possible correlation between radionuclide concentration and the protozoa content of the samples. 7 references, 5 figures.
Date: March 23, 1984
Creator: Marsh, K.V. & Buddemeier, R.W.
Partner: UNT Libraries Government Documents Department
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Quantitative analysis of the hydrothermal system in Lassen Volcanic National Park and Lassen Known Geothermal Resource Area

Description: The Lassen hydrothermal system is in the southern Cascade Range, approximately 70 kilometers east-southeast of Redding, California. The conceptual model of the Lassen system is termed a liquid-dominated hydrothermal system with a parasitic vapor-dominated zone. The essential feature of this model is that steam and steam-heated discharge at relatively high elevations in Lassen Volcanic National Park (LVNP) and liquid discharge with high chloride concentrations at relatively low elevations outside LVNP in the Lassen Known Geothermal Resource Area (KGRA) are both fed by an upflow of high-enthalpy, two-phase fluid within the Park. Liquid flows laterally away from the upflow area towards the areas of high-chloride discharge, and steam rises through a vapor-dominated zone to feed the steam and steam-heated features. The geometric model corresponds to an areally restricted flow regime that connects the Bumpass Hell area in LVNP with regions of chloride hot springs in the Mill Creek canyon in the KGRA south of LVNP. Simulations of thermal fluid withdrawal in the Mill Creek Canyon were carried out in order to determine the effects of such withdrawal on portions of the hydrothermal system within the Park. 19 refs., 17 figs., 4 tabs.
Date: January 1, 1984
Creator: Sorey, M.L. & Ingebritsen, S.E.
Partner: UNT Libraries Government Documents Department
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Pacific Northwest Laboratory, annual report for 1983 to the DOE Office of Energy Research. Part 4. Physical sciences

Description: Part 4 of the Pacific Northwest Laboratory Annual Report for 1983 to the Office of Energy Research, includes those programs funded under the title Physical and Technological Research. The Field Task Program Studies reports in this document are grouped under the subheadings and each section is introduced by a divider page that indicates the Field Task Agreement reported in that section. These reports only briefly indicate progress made during 1983. The reader should contact the principal investigators named or examine the publications cited for more details.
Date: February 1, 1984
Partner: UNT Libraries Government Documents Department
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Interactions of tailings leachate with local liner materials found at Canonsburg, Pennsylvania.

Description: The mill tailings site at Canonsburg, Pennsylvania is the first mill site to receive remedial action under the Department of Energy's Uranium Mill Tailings Remedial Action Program. Part of this remedial action will require excavating the 53,500 m/sup 3/ (70,000 yd/sup 3/) of tailings on the site having a specific activity exceeding 100 pCi/g, and encapsulating these contaminated tailings in a clay-lined cell. As part of the remedial action effort, Pacific Northwest Laboratory has been studying the interactions of tailings and tailings leachate with locally occurring clays proposed for liner materials. These studies include physical and chemical characterization of amended and unamended local clays, chemical characterization of the tailings, column studies of tailings leached with deionized water, and column studies of clays contacted with tailings solutions to determine the attenuation properties of the proposed liner materials. Column studies of tailings leached with deionized water indicated that the Canonsburg tailings could represent a source of soluble radium-226 and uranium-238, several trace metals, cations, and the anions SO/sub 4/, NO/sub 3/, and Cl. Of these soluble contaminants, uranium-238, radium-226, the trace metals As and Mo, and the anions F and SO/sub 4/ were present at levels exceeding maximum concentration levels in the tailings leaching column effluents. However, local clays, both in amended and unamended form were effective in attenuating contaminant migration. The soil amendments tested failed to increase radium attenuation. The tailings leaching studies indicated that the tailings will produce leachates of neutral pH and relatively low contaminant levels for at least 200 years. We believe that compacting the tailings within the encapsulation cell will help to reduce leaching of contaminants from the liner system, since very low permeabilities (<10/sup -8/ cm/s) were observed for even slightly compacted tailings materials.
Date: April 1, 1984
Creator: Dodson, M.E.; Gee, G.W. & Serne, R.J.
Partner: UNT Libraries Government Documents Department
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Damage nucleation in Si during ion irradiation

Description: Damage nucleation in single crystals of silicon during ion irradiation is investigated. Experimental results and mechanisms for damage nucleation during both room and liquid nitrogen temperature irradiation with different mass ions are discussed. It is shown that the accumulation of damage during room temperature irradiation depends on the rate of implantation. These dose rate effects are found to decrease in magnitude as the mass of the ions is increased. The significance of dose rate effects and their mass dependence on nucleation mechanisms is discussed.
Date: January 1, 1984
Creator: Holland, O.W.; Fathy, D. & Narayan, J.
Partner: UNT Libraries Government Documents Department
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Retrospective examination of geothermal environmental assessments

Description: Since 1976, the Department of Energy (DOE) has supported a variety of programs and projects dealing with the exploration, development, and utilization of geothermal energy. This report presents an overview of the environmental impacts associated with these efforts. Impacts that were predicted in the environmental analyses prepared for the programs and projects are reviewed and summarized, along with measures that were recommended to mitigate these impacts. Also, for those projects that have gone forward, actual impacts and implemented mitigation measures are reported, based on telephone interviews with DOE and project personnel. An accident involving spills of geothermal fluids was the major environmental concern associated with geothermal development. Other important considerations included noise from drilling and production, emissions of H/sub 2/S and cooling tower drift, disposal of solid waste (e.g., from H/sub 2/S control), and the cumulative effects of geothermal development on land use and ecosystems. Mitigation measures were frequently recommended and implemented in conjunction with noise reduction; drift elimination; reduction of fugitive dust, erosion, and sedimentation; blowout prevention; and retention of wastes and spills. Monitoring to resolve uncertainties was often implemented to detect induced seismicity and subsidence, noise, drift deposition, concentrations of air and water pollutants, and effects on groundwater. The document contains an appendix, based on these findings, which outlines major environmental concerns, mitigation measures, and monitoring requirements associated with geothermal energy. Sources of information on various potential impacts are also listed.
Date: March 1, 1984
Creator: Webb, J. W.; Eddlemon, G. K. & Reed, A. W.
Partner: UNT Libraries Government Documents Department
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Murakami density limit in tokamaks and reversed-field pinches

Description: A theoretical upper limit for the density in an ohmically heated tokamak discharge follows from the requirement that the ohmic heating power deposited in the central current-carrying channel exceed the impurity radiative cooling in this critical region. A compact summary of our results gives this limit n/sub M/ for the central density as n/sub M/ = (Z/sub e//(Z/sub e/-1)/sup 1/2/n/sub eo/ (B/sub T//1T)(1m/R) where n/sub eo/ depends strongly on the impurity species and is remarkably independent of the central electron temperature T/sub e/(0). For T/sub e/(0) approx. 1 keV, we have n/sub eo/ = 1.5 x 10/sup 14/ cm/sup -3/ for beryllium, n/sub eo/ = 5 x 10/sup 13/ cm/sup -3/ for oxygen, n/sub eo/ = 1.0 x 10/sup 13/ cm/sup -3/ for iron, and n/sub eo/ = 0.5 x 10/sup 13/ cm/sup -3/ for tungsten. The results agree quantitatively with Murakami's original observations. A similar density limit, known as the I/N limit, exists for reversed-field pinch devices and this limit has also been evaluated for a variety of impurity species.
Date: March 1, 1984
Creator: Perkins, F.W. & Hulse, R.A.
Partner: UNT Libraries Government Documents Department
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Second Nuclear Era

Description: The Institute for Energy Analysis with support from The Andrew W. Mellon Foundation has studied the decline of the present nuclear era in the United States and the characteristics of a Second Nuclear Era which might be instrumental in restoring nuclear power to an appropriate place in the energy options of our country. The study has determined that reactors operating today are much safer than they were at the time of the TMI accident. A number of concepts for a supersafe reactor were reviewed and at least two were found that show considerable promise, the PIUS, a Swedish pressurized water design, and a gas-cooled modular design of German and US origin. Although new, safer, incrementally improved, conventional reactors are under study by the nuclear industry, the complete lack of new orders in the United States will slow their introduction and they are likely to be more expensive than present designs. The study recommends that supersafe reactors be taken seriously and that federal and private funds both be used to design and, if feasible, to build a prototype reactor of substantial size. 146 references, 8 figures, 2 tables.
Date: March 1, 1984
Creator: Weinberg, Alvin M.; Spiewak, Irving; Barkenbus, Jack N.; Livingston, Robert S. & Phung, Doan L.
Partner: UNT Libraries Government Documents Department
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Measurements of the dependence of damage thresholds on laser wavelength, pulse duration and film thickness

Description: Results of three experiments will be described. We used 351-nm and 355-nm pulses with durations of 0.6, 1, 5 and 9 ns measure thresholds for a variety of anti-reflectance and high reflectance coatings. The functional form t/sup m/, with t the pulse duration, was used to scale fluence thresholds measured at 0.6 ns to those measured at 9.0 ns. Values of the coefficient m ranged from 0.10 to 0.51. The average value was 0.30. In the second experiment, we measured thresholds at 1064 nm, 527 nm and 355 nm for single-frequency high reflectance ZrO/sub 2//SiO/sub 2/ coatings. Coatings for all three frequencies were deposited simultaneously by use of masks in the coating chamber. Thresholds varied from 2 to 4 J/cm/sup 2/ at 355 nm to 7 to 10 J/cm/sup 2/ at 1064 nm. The third experiment measured thresholds at 355 nm for antireflection coatings made with layer thicknesses varying from greater than one wavelength to less than a quarterwavelength. A significant variation of threshold with coating thickness was not observed, but the median thresholds increased slightly as coating thickness increased.
Date: March 1, 1984
Creator: Rainer, F.; Vercimak, C.L.; Milam, D.; Carniglia, C.K. & Tuttle Hart, T.
Partner: UNT Libraries Government Documents Department
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Mechanical transport in two-dimensional networks of fractures

Description: The objectives of this research are to evaluate directional mechanical transport parameters for anisotropic fracture systems, and to determine if fracture systems behave like equivalent porous media. The tracer experiments used to measure directional tortuosity, longitudinal geometric dispersivity, and hydraulic effective porosity are conducted with a uniform flow field and measurements are made from the fluid flowing within a test section where linear length of travel is constant. Since fluid flow and mechanical transport are coupled processes, the directional variations of specific discharge and hydraulic effective porosity are measured in regions with constant hydraulic gradients to evaluate porous medium equivalence for the two processes, respectively. If the fracture region behaves like an equivalent porous medium, the system has the following stable properties: (1) specific discharge is uniform in any direction and can be predicted from a permeability tensor; and (2) hydraulic effective porosity is directionally stable. Fracture systems with two parallel sets of continuous fractures satisfy criterion 1. However, in these systems hydraulic effective porosity is directionally dependent, and thus, criterion 2 is violated. Thus, for some fracture systems, fluid flow can be predicted using porous media assumptions, but it may not be possible to predict transport using porous media assumptions. Two discontinuous fracture systems were studied which satisfied both criteria. Hydraulic effective porosity for both systems has a value between rock effective porosity and total porosity. A length-density analysis (LDS) of Canadian fracture data shows that porous media equivalence for fluid flow and transport is likely when systems have narrow aperture distributions. 54 references, 90 figures, 7 tables.
Date: April 1, 1984
Creator: Endo, H.K.
Partner: UNT Libraries Government Documents Department
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Inspection of the Heber binary-cycle geothermal project

Description: We concluded that DOE had effective management control procedures to monitor project costs and the design, construction and demonstration activities. Lessons learned from previous DOE geothermal projects were applied and technical information generated from the Heber plant will be transferred to the public and private sectors by the project participants. We also identified the following issues that concerned us: Revenue Sharing: under existing revenue sharing provisions in the Cooperative Agreement, we estimate that reimbursable revenues to DOE will range between $30.5 million and $51.6 million. DOE and the public should be reimbursed for the total contribution of $61 million because the plant, if commercialized, will primarily benefit ratepayers and stockholders of San Diego Gas and Electric Company (SDG and E); Project Office Support Contracts: Our analyses of a number of project office support contracts suggest that some of this work should be cost shared with SDG and E; in other cases, the value of the work is questionable and appears to be an unnecessary expenditure of DOE funds; and Questionable Contractor Procurement: the noncompetitive procurement of a private firm to develop an economic study of a second Heber plant appears to be unjustified and duplicates work already planned by project participants. Comments on a draft of this report were received from the Acting Assistant Secretary for Conservation and Renewable Energy and from Heber program and project managers.
Date: March 28, 1984
Partner: UNT Libraries Government Documents Department
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Recent progress on ATF

Description: The ATF experiment will test improvements to high-beta, steady-state toroidal confinement using external helical fields. The device design has been optimized to (1) provide direct access to the high-beta second-stability regime, (2) have sufficient flexibility to study a large range of toroidal configurations both with and without plasma current, (3) test the reduction of low-collisionality transport by EXB drifts induced by the self-consistent radial electric field, and (4) permit steady-state, high-beta operation without disruptions. Continued physics studied at ORNL and recent results from foreign stellarator experiments have increased confidence in ATF performance.
Date: January 1, 1984
Creator: Neilson, G.H.
Partner: UNT Libraries Government Documents Department
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Response of a glass melter to steam explosion

Description: As part of the safety assessment in the design of the glass melter for large-scale immobilization of high-level radioactive wastes, structural considerations of the containment shell include its dynamic responses to abnormal loading conditions such as that caused by a steam explosion. The postulated steam explosion, conservatively given an energy content equivalent to 13 pounds of TNT, is capable of exerting sudden pressures greater than 300 psi but less than 410 psi on the melter wall. By use of thin-shell theory, the equations of motion satisfying the discontinuity conditions at junctions of shells with different curvatures are solved analytically. Results of stress analysis ensure elastic responses of the containment structure of the melter. 6 references, 3 figures, 1 table.
Date: January 1, 1984
Creator: Yau, W. F. & Durant, W. S.
Partner: UNT Libraries Government Documents Department
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Analysis of fracture modes during extrusion and drawing of bimetal rods or wire. Analytical study of drawing and extrusion of superconducting filamentary wires: fracture problems and evaluation of temperature rise. Final report

Description: Based on the upper-bound theorem in limit analysis, a theoretical model describing sound flow, core fracture, and sleeve fracture in bimetal rods and wire during extrusion and drawing was developed. The variables affecting core and sleeve fracture are: reduction in area, die geometry, friction, relative size and strength of the core, and applied surface tractions. Within the wide range of combinations of these process variables, only a small range permits co-extrusion and codrawing without fracture. Criteria for the prevention of core and sleeve fracture during co-extrusion and core fracture during co-drawing were developed and presented graphically in this study. The results were applied to the central burst problem during extrusion and drawing of homogeneous materials.
Date: January 9, 1984
Creator: Avitzur, B.; Wu, R.; Chou, Y.T. & Talbert, S.
Partner: UNT Libraries Government Documents Department
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Innovative approach to asbestos removal

Description: The most common asbestos materials used at the Savannah River site include: steam pipe insulation; powerhouse boiler insulation; wallboards; roofing materials; and cement products. Asbestos was also found in a number of other materials: aprons; gaskets; laboratory hot pads; and talcum powder used for gloves. Techniques for removal; personnel training; mechanical ventilation; and personnel isolation techniques are described for completing asbestos removal safely and without boiler downtime. (PSB)
Date: January 1, 1984
Creator: Kahal, E J
Partner: UNT Libraries Government Documents Department
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EPICS System: An Overview

Description: This paper presents an overview of the EPICS control system at FERMILAB. EPICS is a distributed, multi-user, interactive system for the control and monitoring of particle beamlines at a high-energy experimental physics laboratory. The overview discusses the operating environment of the control system, the requirements which determined the design decisions, the hardware and software configurations, and plans for the future growth and enhancement of the present system. This paper is the first of three related papers on the EPICS system. The other two cover (1) the system structure and user interface and (2) RSX implementation issues.
Date: February 1, 1984
Creator: Bartlett, J. F.; Bobbitt, J. S.; Kramper, B. J.; Lahey, T. E.; MacKinnon, B. A. & West, R. E.
Partner: UNT Libraries Government Documents Department
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Case study of the Wendel-Amedee Exploration Drilling Project, Lassen County, California, User Coupled Confirmation Drilling Program

Description: The Wendel-Amedee KGRA is located in Honey Lake basin in Lassen County, California, on the boundary between the Modoc Plateau and the Basin and Range geologic provinces. A variety of geophysical surveys was performed over the project property. Geophysical data helped in establishing the regional structural framework, however, none of the geophysical data is sufficiently refined to be considered suitable for the purpose of siting an exploration drill hole. Drilling of reservoir confirmation well WEN-1 took place from August 1 to September 22, 1981. Pulse and long-term flow testing subjected the reservoir to a maximum flow of 680 gpm for 75 hours. At that rate, the well exhibited a productivity index of 21.6 gpm/psi; the reservoir transmissivity was 3.5 x 10/sup 6/ md-ft/cp. The maximum bottom-hole temperature recorded during testing was 251/sup 0/F. The conceptual model of the geothermal resource at Wendel Hot Springs calls on ground water, originating in the neighboring volcanic highlands, descending through jointed and otherwise permeable rocks into the granitic basement. Once in the basement, the fluid is heated as it continues its descent, and lateral movement as dictated by the hydrologic gradient. It then rises to the discharge point along transmissive faults. 45 refs., 28 figs., 3 tabs.
Date: September 1, 1984
Creator: Zeisloft, J.; Sibbett, B.S. & Adams, M.C.
Partner: UNT Libraries Government Documents Department
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Structural materials for breeder reactor cores and coolant circuits

Description: The structural components of principal interest in LMFBR cores and cooling circuits include the reactor vessel, primary and secondary piping, intermediate heat exchanger (IHX), and steam generator. Load-bearing components inside the vessel, among these the fuel cladding and duct, are also included. The operating conditions present in a fast-breeder nuclear reactor impose a number of requirements on the mechanical, physical, and neutronic properties of the materials used to construct these components.
Date: February 1, 1984
Creator: Diercks, D. R.
Partner: UNT Libraries Government Documents Department
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Fermilab 200 MeV linac control system hardware

Description: This report is a description of the present Linac distributed control system that replaces the original Xerox computer and interface electronics with a network of 68000-based stations. In addition to replacing the obsolete Xerox equipment, goals set for the new system were to retain the fast response and interactive nature of the original system, to improve reliability, to ease maintenance, and to provide 15 Hz monitoring of all Linac parameters. Our previous experience with microcomputer installations showed that small, stand-alone control systems are rather straightforward to implement and have been proven to be reliable in operation, even in the severe environment of the 750-keV preaccelerator. The overall design of the Linac system incorporates the concept of many relatively small, stand-alone control systems networked together using an intercomputer communication network. Each station retains its local control system character but takes advantage of the network to allow an operator to interact with the entire Linac from any local console. At the same time, a link to the central computer system allows Host computers to also access parameters in the Linac.
Date: January 1, 1984
Creator: Shea, M.F.
Partner: UNT Libraries Government Documents Department
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Direct spectroscopic observation of charge-exchange recombination of medium-Z elements in the PLT tokamak

Description: We report the first observation of line emission resulting directly from charge-exchange recombination of medium-Z elements (Al, Sc) injected into a PLT discharge. Transitions due to the radiative cascade immediately following charge-exchange of He-like Al and Sc were observed by a VUV spectrograph and two air monochromators. In two cases, AlXI 3209 A and ScXIX 112.1 A, the observed transition had not previously been experimentally identified. Spatial scans provided information on the profile of the neutral beam in the plasma.
Date: March 1, 1984
Creator: Skinner, C. H.; Suckewer, S.; Cohen, S. A.; Schilling, G.; Wilson, R. & Stratton, B.
Partner: UNT Libraries Government Documents Department
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Magnetic excitations in transition-metal ferromagnets. Recent progress and future prospects on neutron scattering experiments

Description: A review is given on current neutron scattering experiments at Brookhaven National Laboratory on transition-metal ferromagnets Ni, Fe, Pd/sub 2/MnSn and MnSi. The scattering intensity in constant-energy scans, observed above T/sub c/ in all of these materials, exhibited a clear peak at finite momentum transfers. Using a simple scattering function with double-Lorentzian shape, we demonstrate that this peak is a manifestation of simple diffusive spin fluctuations. Experimental results of several parameters are compared in the context of localized-moment and itinerant-electron pictures. The ratio of spin wave stiffness constant D and transition temperature kT/sub c/ is shown to be a good yardstick for the degree of itinerancy of d-electrons. 36 references.
Date: January 1, 1984
Creator: Uemura, Y.J.
Partner: UNT Libraries Government Documents Department
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Rapid seepage of contaminants through the highwall of a uranium mill tailings pit. [MIGRAT]

Description: A computer code (MIGRAT) is used to quantify the migration of moisture and multiple retarded contaminants in the unsaturated zone and assess the impact of open mine disposal of uranium mill tailings. The model is applied to a generic uranium mill tailings. The model is applied to a generic uranium mill tailings pit constructed with a clay-lined bottom and steep unlined sidewalls. The migration of a two contaminant system is modeled assuming that neither contaminant decays and only one contaminant is retarded. This study shows the anticipated result that the major pathway from the pit to the underlying water table is through the sidewall and that the time scales for this pathway are much shorter than those associated with the clay liner. More importantly, this study reveals that due to the strong nonlinear character of the hydraulic properties of unsaturated soils, concentrations of the retarded contaminant may only slightly lag the nonretarded contaminant through this pathway and contamination of the uppermost aquifer by the retarded contaminant may occur shortly after contamination by the nonretarded contaminant. 2 references, 5 figures.
Date: January 1, 1984
Creator: Pin, F.G.; Witten, A.J.; Sharp, R.D. & Long, E.C.
Partner: UNT Libraries Government Documents Department
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Oxidation/gasification of carbon residue on retorted oil shale. Final report

Description: Studies of the oxidation and gasification of oil shale char were extended to an investigation of the effects of mineral catalysis. Six shales with differing mineral compositions were studied, including samples from the saline zone in the Western Colorado and from the Antrim shales of Michigan. Oxidation kinetics data, corrected for mass transfer effects, were compared for all six samples. A high assay shale from Utah and a sample from the saline zone were found to have the highest oxidation rates. By examining the data for shales which were water leached and thermally pretreated, it was concluded that both NaO and CaO act as oxidation catalysts. However, as a result of mineral decomposition experiments conducted with a sample from the C-a lease tract, it appears as though the ankeritic dolomite fraction will not decompose as long as there is a minimal CO/sub 2/ over pressure. Rather, low temperature silication reactions appear to take place once the temperature exceeds 925/sup 0/K. An extensive evaluation was also completed for the gasification of an Antrim shale from Michigan. Both the rates of CO/sub 2/ and steam gasification of the char were found to be markedly lower than that observed for a shale sample from the Parachute Creek member in Colorado. However, unlike the Colorado shale, the make gas resulting from the steam gasification of the Antrim shale produced nearly equal quantities of CO and CO/sub 2/. Thus, despite the high concentration of iron in the Antrim shale, the water gas shift reaction is not catalyzed nearly to the same extent as in western shales.
Date: January 16, 1984
Creator: Thomson, W. J.
Partner: UNT Libraries Government Documents Department
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