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Kinetics experiments and bench-scale system: Background, design, and preliminary experiments

Description: The project, Supercritical Water Oxidation of Hazardous Chemical Waste, is a Hazardous Waste Remedial Actions Program (HAZWRAP) Research and Development task being carried out by the Los Alamos National Laboratory. Its objective is to obtain information for use in understanding the basic technology and for scaling up and applying oxidation in supercritical water as a viable process for treating a variety of DOE-DP waste streams. This report gives the background and rationale for kinetics experiments on oxidation in supercritical water being carried out as a part of this HAZWRAP Research and Development task. It discusses supercritical fluid properties and their relevance to applying this process to the destruction of hazardous wastes. An overview is given of the small emerging industry based on applications of supercritical water oxidation. Factors that could lead to additional applications are listed. Modeling studies are described as a basis for the experimental design. The report describes plug flow reactor and batch reactor systems, and presents preliminary results. 28 refs., 4 figs., 5 tabs.
Date: October 1, 1987
Creator: Rofer, C.K.
Partner: UNT Libraries Government Documents Department

The destruction of hazardous chemical waste by oxidation in supercritical water

Description: The chemistry of oxidation in supercritical water is being investigated for development into a practical destruction process for hazardous chemical waste. In principle, a wide variety of waste streams might be treated by this technology, including those that are unsuitable for incineration because of high water content. To establish a basis for extrapolation of kinetic measurements to a variety of compounds, a mechanism is being developed for oxidation in supercritical water on the basis of conventional free-radical reactions, with modifications for high pressures and high concentrations of water. Global rate expressions for oxidation of methane and methanol in supercritical water have been determined. A base mechanism and modifications to the mechanism to account for the roles of hydrogen bonding and water dimer formation have been investigated for CO. On this limited basis, reasonable agreement between model and experimental results has been obtained. Further verification of the model with experimental results will provide insight into the roles of hydrogen bonding and water dimer formation in oxidation in supercritical water. 30 refs., 3 tabs.
Date: January 1, 1989
Creator: Rofer, C.K. & Streit, G.E.
Partner: UNT Libraries Government Documents Department

Packaging of plutonium metal and oxide in the ARIES project

Description: The objective of the Advanced Recovery and Integrated Extraction System (ARIES) Project is to demonstrate technology to dismantle plutonium pits from excess nuclear weapons, convert the plutonium to a metal ingot or an oxide powder, package the metal or oxide, and verify the contents of the package by nondestructive assay. The packaged weapons plutonium will be converted to mixed oxide reactor fuel or immobilized in ceramic forms suitable for geologic storage. The packaging of the material must therefore be suitable for storage until the material is further processed. A set of containers for plutonium metal and oxide has been developed to meet the needs of the ARIES process and the Department of Energy requirements for long-term storage. The package has been developed and qualified with the participation of private companies.
Date: December 1, 1998
Creator: Rofer, C.K.; Martinez, D.A. & Trujillo, V.L.
Partner: UNT Libraries Government Documents Department

Waste site characterization through digital analysis of historical aerial photographs at Los Alamos National Laboratory and Eglin Air Force Base

Description: Historical aerial photographs are used to provide a physical history and preliminary mapping information for characterizing hazardous waste sites at Los Alamos National Laboratory and Eglin Air Force Base. The examples cited show how imagery was used to accurately locate and identify previous activities at a site, monitor changes that occurred over time, and document the observable of such activities today. The methodology demonstrates how historical imagery (along with any other pertinent data) can be used in the characterization of past environmental damage.
Date: May 1, 1995
Creator: Van Eeckhout, E.; Pope, P.; Wells, B.; Rofer, C. & Martin, B.
Partner: UNT Libraries Government Documents Department

Laser-initiated chain reactions in the partial oxidation of methane

Description: Using laser photolysis of suitable precursor molecules to produce gas-phase free radicals, we have been studying important kinetic processes in the partial oxidation of methane. Prompt production of a relatively high concentration of free radicals via laser photolysis makes it possible to separate the thermal initiation step from the subsequent chain propagation steps. Since the conditions (temperature, pressure, and mixture composition) for rapid thermal initiation and optimum production may differ, this provides an exciting potential application for laser-induced chemistry where the laser acts as the initiation source. We report our results on the partial oxidation of methane by oxygen at moderate temperatures. A trace amount of acetone is photolyzed at 193 nm a prompt source of methyl radicals in methane-oxygen mixtures. Details of the proposed mechanism are discussed as well as application of the technique to technologies for methane conversion to transportable fuels such as methanol. 15 refs., 6 figs.
Date: January 1, 1986
Creator: Baughcum, S.L.; Oldenborg, R.C.; Danen, W.C.; Streit, G.E. & Rofer, C.
Partner: UNT Libraries Government Documents Department

Packaging of Plutonium Metal and Oxide in the ARIES Project

Description: The objective of the Advanced Recovery and Integrated Extraction System (ARIES) Project is to demonstrate technology to dismantle plutonium pits from excess nuclear weapons, convert the plutonium to a metal ingot or an oxide powder, package the metal or oxide, and verify the contents of the package by nondestructive assay. The packaged weapons plutonium will be converted to mixed-oxide reactor fuel or immobilized in ceramic forms suitable for geologic storage. The packaging of the material must therefore be suitable for storage until the material is further processes. A set of containers for plutonium metal and oxide has been developed to meet the needs of the ARIES process and the Department of Energy requirements for long-term storage. The package has been developed and qualified with the participation of private companies.
Date: November 9, 1998
Creator: Rofer, C. K.; Martinez, D. A. & Trujillo, V. L.
Partner: UNT Libraries Government Documents Department

Methane to methanol conversion

Description: The purpose of this project is to develop a novel process by which natural gas or methane from coal gasification products can be converted to a transportable liquid fuel. It is proposed that methanol can be produced by the direct, partial oxidation of methane utilizing air or oxygen. It is anticipated that, compared to present technologies, the new process might offer significant economic advantages with respect to capital investment and methane feedstock purity requirements. Results to date are discussed. 6 refs.
Date: January 1, 1990
Creator: Finch, F.T.; Danen, W.C.; Lyman, J.L.; Oldenborg, R.C.; Rofer, C.K. & Ferris, M.J.
Partner: UNT Libraries Government Documents Department

Development of weld closure stations for plutonium long-term storage containers

Description: Weld closure stations for plutonium long-term storage containers have been designed, fabricated, and tested for the Advanced Recovery and Integrated Extraction System (ARIES) at the TA-55 Plutonium Facility of the Los Alamos National Laboratory. ARIES is a processing system used for the dismantlement of the plutonium pits from nuclear weapons. ARIES prepares the extracted-plutonium in a form which is compatible with long-term storage and disposition options and meets international inspection requirements. The processed plutonium is delivered to the canning module of the ARIES line, where it is packaged in a stainless steel container. This container is then packaged in a secondary container for long-term storage. Each of the containers is hermetically sealed with a full penetration weld closure that meets the requirements of the ASME Section IX Boiler and Pressure Vessel Code. Welding is performed with a gas tungsten arc process in an inert atmosphere of helium. The encapsulated helium in the nested containers allows for leak testing the weld closure and container. The storage package was designed to meet packaging requirements of DOE Standard 3013-96 for long-term storage of plutonium metal and oxides. Development of the process parameters, weld fixture, weld qualification, and the welding chambers is discussed in this paper.
Date: December 31, 1998
Creator: Fernandez, R.; Martinez, D.A.; Martinez, H.E.; Nelson, T.O.; Ortega, R.E.; Rofer, C.K. et al.
Partner: UNT Libraries Government Documents Department

Environmental waste site characterization utilizing aerial photographs, remote sensing, and surface geophysics

Description: Six different techniques were used to delineate 40 year old trench boundary at Los Alamos National Laboratory. Data from historical aerial photographs, a magnetic gradient survey, airborne multispectral and thermal infra-red imagery, seismic refraction, DC resistivity, and total field magnetometry were utilized in this process. Each data set indicated a southern and northern edge for the trench. Average locations and 95% confidence limits for each edge were determined along a survey line perpendicular to the trench. Trench edge locations were fairly consistent among all six techniques. Results from a modeling effort performed with the total magnetic field data was the least consistent. However, each method provided unique and complementary information, and the integration of all this information led to a more complete characterization of the trench boundaries and contents.
Date: April 18, 1996
Creator: Pope, P.; Van Eeckhout, E.; Rofer, C.; Baldridge, S.; Ferguson, J.; Jiracek, G. et al.
Partner: UNT Libraries Government Documents Department

Destruction of explosives and rocket fuels by supercritical water oxidation

Description: Traditional methods for disposing of PEPs have been open burning or open detonation (OB/OD); however, regulatory agencies are likely to prohibit OB/OD because of the uncontrolled air emissions and soil contaminations. Likewise, controlled incineration carries a liability for air pollution because large quantities of NO{sub x} are produced in the conventional combustion chemistry of PEPS. Soil and ground water have already been contaminated with PEPs through normal operations at manufacturing plants and military bases. Incineration can be used for decontamination of these soils, with the associated liability for air pollution, but few satisfactory and economic methods exist for ground water decontamination. A clear need exists for improved disposal and destruction methods. The destruction of energetic materials, including propellants, explosives and pyrotechnics (PEPS) by oxidation in supercritical water is described. The focus is on the chemistry of the process. The destruction efficiencies and products of reaction contained in the aqueous and gaseous effluents of several representative PEPs are reported.
Date: January 1, 1992
Creator: Dyer, R.B.; Buelow, S.J.; Harradine, D.M.; Robinson, J.M.; Foy, B.R.; Atencio, J.H. et al.
Partner: UNT Libraries Government Documents Department