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Measurements of Al(NO sub 3 ) sub 3 activities in aqueous nitrate solutions

Description: Aluminum nitrate activity coefficient obtained by vapor pressure osmometry are compared with activity coefficients derived from nitric acid extraction measurements using Bromley's correlation. This solvent extraction approach was possible because of the poor extraction of Al{sup 3+}(D{sub Al} {le} 10{sup {minus}3}) by the chosen solvents. The solvent compositions were 0.25M CMPO (octyl(phenyl)-N,N-diisobutylcarbamoyl-methylphosphine oxide) in tetrachloroethylene (TCE) and 0.25M CMPO with 0.75M tributyle phosphate (TBP) in TCE. In both approaches, nitric acid was used to supress the hydrolysis of Al{sup 3+}. At high ionic strengths, the two techniques yielded very similar activity coefficients for Al(NO{sub 3}){sub 3}. However, at intermediate and very low ionic strengths, the two procedures produced activity coefficients which differed considerably from each other. 2 figures, 3 tables, 18 references.
Date: January 1, 1992
Creator: Chaiko, D. J.; Fredrickson, D. R.; Difilippo, A. A.; Smidt, S. M.; Vandegrift, G. F. (Argonne National Lab., IL (United States)) & Tasker, I. R. (National Inst. for Petroleum and Energy Research, Bartlesville, OK (United States))
Partner: UNT Libraries Government Documents Department

Monolithic Nickel (II) Oxide Aerogels Using an Organic Epoxide: The Importance of the Counter Ion

Description: The synthesis and characterization of nickel (II) oxide aerogel materials prepared using the epoxide addition method is described. The addition of the organic epoxide propylene oxide to an ethanolic solution of NiCl{sub 2} 6H{sub 2}O resulted in the formation of an opaque light green monolithic gel and subsequent drying with supercritical CO{sub 2} gave a monolithic aerogel material of the same color. This material has been characterized using powder X-ray diffraction, electron microscopy, elemental analysis, and nitrogen adsorption/desorption analysis. The results indicate that the nickel (II) oxide aerogel has very low bulk density (98 kg/m{sup 3} ({approx}98 %porous)), high surface area (413 m{sup 2}/g), and has a particulate-type aerogel microstructure made up of very fine spherical particles with an open porous network. By comparison, a precipitate of Ni{sub 3}(NO{sub 3}){sub 2}(OH){sub 4} is obtained when the same preparation is attempted with the common Ni(NO{sub 3}){sub 2} 6H{sub 2}O salt as the precursor. The implications of the difference of reactivity of the two different precursors are discussed in the context of the mechanism of gel formation via the epoxide addition method. The synthesis of nickel (II) oxide aerogel, using the epoxide addition method, is especially unique in our experience. It is our first example of the successful preparation of a metal oxide aerogel using a metal divalent metal ion and may have implications for the application of this method to the preparation of aerogels or nanoparticles of other divalent metal oxides. To our knowledge this is the first report of a monolithic pure nickel (II) oxide aerogel materials.
Date: January 13, 2004
Creator: Gash, A E; Satcher, J H & Simpson, R L
Partner: UNT Libraries Government Documents Department

Assessment of Physical Properties of Transuranic Waste in Hanford Single-Shell Tanks

Description: CH2M HILL Hanford Group, Inc. (CH2M HILL) is in the process of identifying and developing supplemental process technologies to accelerate the tank waste cleanup mission. One technology targets disposal of Hanford transuranic (TRU) process wastes stored in single-shell tanks (SSTs). Ten Hanford SSTs are candidates for designation as contact-handled TRU waste type: the B-200 series tanks (241-B-201, -B-202, -B-203, and -B-204), the T-200 series tanks (241-T-201, -T-202, -T-203, and -T-204), and Tanks 241-T-110 and T-111. Current plans identify a process in which these wastes are retrieved from the tanks, either dry or with a recycled liquid stream to help mobilize the waste in the tank and through transfer lines and vessels, dewatered to remove excess liquid, and transferred to waste packages in a form suitable for disposal. CH2M HILL seeks to procure a process for dewatering, handling, and packaging the contact-handled TRU waste after it is retrieved. An understanding of waste physical properties is needed to support design of the SST TRU handling and packaging system and to produce suitable physical simulants to test such a process. Pacific Northwest National Laboratory (PNNL) has been tasked with developing these waste simulants. This report summarizes PNNL's assessment of available waste physical property information for the 10 candidate TRU SSTs. Data sources include the Hanford Tank Waste Information Network System (TWINS) database, technical reports, and visual observations from the review of photographs and videotape recordings taken during the extrusion of various SST TRU waste core samples. While the retrieval process is expected to alter certain waste physical properties such as shear strength, the effects of this process on waste properties cannot yet be quantified. Therefore, the scope of this report is to describe the properties of SST TRU wastes as they are known for unprocessed wastes or, in some cases, for diluted waste ...
Date: March 5, 2003
Creator: Rassat, Scot D.; Mahoney, Lenna A.; Wells, Beric E.; Mendoza, Donaldo P. & Caldwell, Dustin D.
Partner: UNT Libraries Government Documents Department

Radiation Damage Effects in Candidate Ceramics for Plutonium Immobilization: Final Report

Description: In this document, we summarize our study of the effects of radiation induced damage to the titanate ceramics that were to be the immobilization form for surplus weapons-grade Pu. In this study, we made five ceramic materials: pure-phase pyrochlore, pure-phase zirconolite, pyrochlore-rich baseline, zirconolite-rich baseline, and impurity baseline. Two-hundred specimens were made of which 130 contained approximately 10 mass% 238Pu and 70 contained 10 mass% 239Pu. The specimens containing 239Pu served as materials against which the behavior of the 238Pu-bearing specimens could be compared. In our studies, we measured the true density (density exclusive of surface connected porosity), bulk density, crystalline-phase composition with X-ray diffraction (XRD), and dissolution rates as radiation induced damage accumulated in the 238Pu-bearing specimens. We routinely took photographs of the specimens during each characterization period. From our studies, we determined that these materials swell less than 10% and generally less than 5%. As the material swells, some open porosity can be converted to closed porosity, often causing the true density to decrease more rapidly than the bulk density. In general, 3?1018 a/g of damage accumulation were required for the materials to become amorphous as determined with the XRD method. The order in which the phases became amorphous was brannerite, pyrochlore, and zirconolite with brannerite being the most susceptible to radiation induced damage. However, we also show that Pu is not evenly distributed amongst the phases when multiple phases are present. We were unsuccessful in making a pure brannerite to study. Therefore, the brannerite was always present with other phases. For a material containing about 10 mass% 239Pu, 3?1018 a/g represent about 500 years in the geologic repository. At no time in our studies was there evidence for microcracking in these materials, even upon close examination in a scanning-electron microscope . Upon careful comparison between the dissolution ...
Date: February 1, 2004
Creator: Strachan, Denis M.; Scheele, Randall D.; Icenhower, Jonathan P.; Buck, Edgar C.; Kozelisky, Anne E.; Sell, Rachel L. et al.
Partner: UNT Libraries Government Documents Department

ASSESSMENT OF RADIONUCLIDE RELEASE FROM INTACT STRUCTURES BACKFILLED WITH CONTAMINATED CONCRETE AT THE YANKEE NUCLEAR POWER STATION.

Description: This calculation determines the release of residual radioactivity (including H-3, C-14, Co-60, Ni-63, Sr-90, and Cs-137), from subsurface structures filled with concrete debris at the Yankee Nuclear Power Station. Analyses were performed to assess the rate of release from the source of contamination and the resulting dose in the groundwater pathway. Two mechanisms were considered, diffusive release from the concrete structures (walls and floors) that remain intact and sorption onto concrete backfill placed within these structures. RESRAD was used to calculate the predicted maximum dose assuming a unit loading of 1 pCi/g on the intact structures. To the extent possible, the same assumptions in the soil DCGL calculations performed for Yankee Atomic were used in the calculation. However, modifications to some input parameter values were needed to represent the geometry of the subsurface facilities, flow through these facilities, and releases from the backfill and intact structures. Input parameters specific to these calculations included the leach rate, disposal geometry, pumping rate, porosity and bulk density. The dose results for a unit loading of 1 pCi/g on intact structures showed that Sr-90 had the highest dose (3.67E-02 mrem/yr).
Date: September 30, 2004
Creator: SULLIVAN, T.
Partner: UNT Libraries Government Documents Department

Characterization of phosphate/sulfate waste grout cores

Description: As part of efforts to clean up federal production sites, the U.S. Department of Energy (DOE) is treating selected low-level liquid wastes by incorporating them into cementitious waste forms. At the Hanford Site, low-level radioactive liquid wastes will be mixed with a blend of Portland cement, fly ash, clays, and other ingredients in a continuous process at the Grout Treatment Facility (GTF). The resulting grout slurry will be pumped to lined, underground concrete vaults where the grout will harden, thereby immobilizing contaminants. Physical property measurements and American Nuclear Society (ANS) 16.1 leach tests have been completed on 45 samples obtained from five cores from the phosphate/sulfate waste (PSW) grout vault. A summary of the compressive strength, bulk density, and sonic velocity data is compared with data from other PSW grout samples. Results of moisture content, thermal conductivity, and the leaching of aluminium, calcium, sodium, sulfate, cobalt-60, and cesium-137 are given.
Date: September 1, 1993
Creator: Martin, P. F. C. & Lokken, R. O.
Partner: UNT Libraries Government Documents Department

Laboratory procedures for waste form testing

Description: The 100 and 300 areas of the Hanford Site are included on the US Environmental Protection Agencies (EPA) National Priorities List under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). Soil washing is a treatment process that is being considered for the remediation of the soil in these areas. Contaminated soil washing fines can be mixed or blended with cementations materials to produce stable waste forms that can be used for beneficial purposes in mixed or low-level waste landfills, burial trenches, environmental restoration sites, and other applications. This process has been termed co-disposal. The Co-Disposal Treatability Study Test Plan is designed to identify a range of cement-based formulations that could be used in disposal efforts in Hanford in co-disposal applications. The purpose of this document is to provide explicit procedural information for the testing of co-disposal formulations. This plan also provides a discussion of laboratory safety and quality assurance necessary to ensure safe, reproducible testing in the laboratory.
Date: September 19, 1994
Creator: Mast, E. S.
Partner: UNT Libraries Government Documents Department

Thermodynamic properties of pulverized coal during rapid heating devolatilization processes. Quarterly progress report, January--March 1994

Description: Knowledge of the thermodynamic and morphological properties of coal associated with rapid heating decomposition pathways is essential to progress in coal utilization technology. Specifically, knowledge of the heat of devolatilization, surface area and density of coal as a function of rank characteristics, temperature and extent of devolatilization in the context of rapid heating conditions is required both, for the fundamental determination of kinetic parameters of coal devolatilization, and to refine existing devolatilization sub-models used in comprehensive coal combustion codes. The objective of this research is to obtain data on the thermodynamic properties and morphology of coal under conditions of rapid heating. Specifically, the total heat of devolatilization, external surface area, BET surface area and true density will be measured for representative coal samples. In addition, for one coal, the contribution of each of the following components to the overall heat of devolatilization will be measured: the specific heat of coal/char during devolatilization, the heat of thermal decompose ion of the coal, the specific heat capacity of tars, and the heat of vaporization of tars. Progress reports are presented for the following tasks: heat of devoltalization of voltaile coal samples; specific heat and heat of fusion of tars; heat of vaporization of tars from rapid heating; and morphological characterization of coal/char samples as a function of extent of devoltalization.
Date: June 1, 1994
Creator: Proscia, W. M. & Freihaut, J. D.
Partner: UNT Libraries Government Documents Department

In-situ grouting of the low-level radioactive waste disposal silos at ORNL`s Solid Waste Storage Area Six

Description: At Oak Ridge National Laboratory (ORNL), one method of solid low-level radioactive waste disposal has been disposed of in below-grade cylindrical concrete silos. Located in Solid Waste Storage Area 6 (SWSA 6), each silo measures 8 ft in diameter and 20 ft deep. Present day operations involve loading the silos with low-level radioactive waste and grouting the remaining void space with a particulate grout of low viscosity. Initial operations involving the disposal of wastes into the below-grade silos did not include the grouting process. Grouting was stated as a standard practice (in late 1988) after discovering that {approximately}75% of the silos accumulated water in the bottom of the silos in the {approximately}2 years after capping. Silo water (leachate) contained a wide range of types and concentrations of radionuclides. The migration of contaminated leachate out of the silo into adjoining soil and groundwater was considered to be a serious environmental concern. This report describes how a specially designed particulate-base grout was used to grout 54 silos previously filled with low-level radioactive waste. Grouting involved three steps: (1) silo preparation, (2) formulation and preparation of the grout mixture, and (3) injection of the grout into the silos. Thirty-five of the 54 silos grouted were equipped with a 3-in.-diam Polyvinyl Chloride (PVC) pipe used to monitor water levels in the silos. A method for rupturing the bottom section of these PVC wells was developed so that grout could be pumped to the bottom of those silos. Holes (2-in. diam) were drilled through the {approximately}18 in. thick concrete to fill the remaining 19 wells without the PVC monitoring wells. The formulation of grout injected into the silos was based on a Portland Type I cement, flyash, sand, and silica fume admixture. Compressive strength of grout delivered to SWSA6 during grouting operations averaged 1,808 lb/in{sup ...
Date: July 1, 1993
Creator: Francis, C. W.; Farmer, C. D. & Stansfield, R. G.
Partner: UNT Libraries Government Documents Department

Measurements of Al(NO{sub 3}){sub 3} activities in aqueous nitrate solutions

Description: Aluminum nitrate activity coefficient obtained by vapor pressure osmometry are compared with activity coefficients derived from nitric acid extraction measurements using Bromley`s correlation. This solvent extraction approach was possible because of the poor extraction of Al{sup 3+}(D{sub Al} {le} 10{sup {minus}3}) by the chosen solvents. The solvent compositions were 0.25M CMPO (octyl(phenyl)-N,N-diisobutylcarbamoyl-methylphosphine oxide) in tetrachloroethylene (TCE) and 0.25M CMPO with 0.75M tributyle phosphate (TBP) in TCE. In both approaches, nitric acid was used to supress the hydrolysis of Al{sup 3+}. At high ionic strengths, the two techniques yielded very similar activity coefficients for Al(NO{sub 3}){sub 3}. However, at intermediate and very low ionic strengths, the two procedures produced activity coefficients which differed considerably from each other. 2 figures, 3 tables, 18 references.
Date: September 1, 1992
Creator: Chaiko, D. J.; Fredrickson, D. R.; Difilippo, A. A.; Smidt, S. M.; Vandegrift, G. F. & Tasker, I. R.
Partner: UNT Libraries Government Documents Department

Preparation and physical properties of U{sub 3}O{sub 8}

Description: Uranyl nitrate solution from 200-Area processing of spent SRP fuel tubes is now sent to Oak Ridge Y-12 for conversion of uranium metal. However, after implementation of the powder metallurgy (P/M) process, U{sub 3}O{sub 8} powder will be needed at SRP but not uranium metal. U{sub 3}O{sub 8} powder for fabrication and irradiation tests was produced during development of P/M at SRL by firing UO{sub 3}, obtained from Y-12, at 800{degrees}C for 6 hours in a low grade nitrogen atmosphere. The UO{sub 3} powder was produced by denitration of unsulfated uranyl nitrate solution. The stoichiometry, particle size distribution, surface area and density of the Y-12 and SRL powders were measured. A comparison was then made between SRL U{sub 3}O{sub 8} produced at 800{degrees}C in nitrogen and in air and U{sub 3}O{sub 8} produced at Y-12 at other heating temperatures.
Date: January 31, 1983
Creator: Peacock, H. B.
Partner: UNT Libraries Government Documents Department

Tank 241-BY-112, cores 174 and 177 analytical results for the final report

Description: Results from bulk density tests ranged from 1.03 g/mL to 1.86 g/mL. The highest bulk density result of 1.86 g/mL was used to calculate the solid total alpha activity notification limit for this tank (33.1 uCi/g), Total Alpha (AT) Analysis. Attachment 2 contains the Data Verification and Deliverable (DVD) Summary Report for AT analyses. This report summarizes results from AT analyses and provides data qualifiers and total propagated uncertainty (TPU) values for results. The TPU values are based on the uncertainties inherent in each step of the analysis process. They may be used as an additional reference to determine reasonable RPD values which may be used to accept valid data that do not meet the TSAP acceptance criteria. A report guide is provided with the report to assist in understanding this summary report.
Date: May 6, 1997
Creator: Nuzum, J. L.
Partner: UNT Libraries Government Documents Department

Characteristics of soils and saprolite in Solid Waste Storage Area 6

Description: Solid Waste Storage Area 6 (SWSA-6) is one of the disposal sites for solid low-level radioactive waste at Oak Ridge National Laboratory. Soils and saprolites from the site were characterized to provide base line information to initiate assessment for remedial actions and closure plans. Physical, chemical, mineralogical, and engineering analyses were conducted on soil and saprolite samples.
Date: September 30, 1987
Creator: Ammons, J. T.; Phillips, D. H.; Timpson, M. E. & Lee, S. Y.
Partner: UNT Libraries Government Documents Department

Tank 241-B-103 tank characterization plan

Description: The Defense Nuclear Facilities Safety Board (DNFSB) has advised the US Department of Energy (DOE) to concentrate the near-term sampling and analysis activities on identification and resolution of safety issues. The data quality objective (DQO) process was chosen as a tool to be used to identify sampling and analytical needs for the resolution of safety issues. As a result, a revision in the Federal Facility Agreement and Consent Order (Tri-Party Agreement or TPA) milestone M-44-00 has been made, which states that ``A Tank Characterization Plan (TCP) will also be developed for each double-shell tank (DST) and single-shell tank (SST) using the DQO process... Development of TCPs by the DQO process is intended to allow users (e.g., Hanford Facility user groups, regulators) to ensure their needs will be met and that resources are devoted to gaining only necessary information.`` This document satisfies that requirement for Tank 241-B-103 (B-103) sampling activities. Tank B-103 was placed on the Organic Watch List in January 1991 due to review of TRAC data that predicts a TOC content of 3.3 dry weight percent. The tank was classified as an assumed leaker of approximately 30,280 liters (8,000 gallons) in 1978 and declared inactive. Tank B-103 is passively ventilated with interim stabilization and intrusion prevention measures completed in 1985.
Date: January 23, 1995
Creator: Carpenter, B. C.
Partner: UNT Libraries Government Documents Department

Stochastic analysis of contaminant transport. Final report, July 1, 1989--November 1, 1991

Description: A reliability algorithm is used to develop probabilistic (stochastic) models or contaminant transport in porous media. The models are based on advective-dispersive transport equations, and utilize the reliability algorithm with existing one- and two-dimensional analytical and numerical solutions. Uncertain variables in the models include: groundwater flow velocity (or permeability in the numerical model), dispersivity, diffusion coefficient, bulk density, porosity, and solute distribution coefficient. Each uncertain variable is assigned a mean, covariance, and marginal distribution. The models yield an estimate of the probability that the contaminant concentration will equal or exceed a target concentration at a selected location and time. The models also yield probabilistic sensitivity measures which identify those uncertain variables with most influence on the probabilistic outcome. The objective of this study is to examine the basic behavior and develop general conclusions regarding transport under certain conditions as modeled using a reliability approach.
Date: February 1, 1992
Creator: Cawlfield, J. D.
Partner: UNT Libraries Government Documents Department

[Dynamic enhanced recovery technologies]. Quarterly technical report, August 1992--October 1993

Description: This paper has presented the investigation of the mechanism of geopressure occurrence, the transition of elastic properties from the hydrostatic pressured formation to the geopressured formation, and finally, a novel seismic amplitude analysis technique to map the top-of-geopresure surface. The successful application of our new technique to the Pleistocene, offshore Louisiana, Gulf of Mexico has again demonstrated that seismic attributes analyses are of importantance in the hydrocarbon exploration. There are three parts in this paper corresponding to the above discussed topics: Part I discusses mechanisms of geopressuring, and the effects of changing porosity, pressure, and fluid saturation on the elastic properties; Part II investigates the controlling factors in the geopressure transition zone, their seismic responses, and theoretical derivations of our new prediction method; and Part III demonstrates the application of the proposed method to the Pleistocene, Offshore Louisiana, Gulf of Mexico, the prediction discrpepancy between the seismic predicted top-of-geopressure and that dericed from 145 well logs, and finally, the importance of this hydrodynamic surface.
Date: October 15, 1993
Creator: Anderson, R. N.
Partner: UNT Libraries Government Documents Department

Fabrication and characterization of MCC approved testing material - ATM-1 glass

Description: The Materials Characterization Center Approved Testing Material ATM-1 is a borosilicate glass that incorporates nonradioactive constituents and uranium to represent high-level waste (HLW) resulting from the reprocessing of commercial nuclear reactor fuel. Its composition is based upon the simulated HLW glass type 76-68 to which depleted uranium has been added as UO/sub 2/. Three separate lots of ATM-1 glass have been fabricated, designated ATM-1a, ATM-1b, and ATM-1c. Limited analyses and microstructural evaluations were conducted on each type. Each lot of ATM-1 glass was produced from a feedstock melted in an air atmosphere at between 1150 to 1200/sup 0/C and cast into stress annealed rectangular bars. Bars of ATM-1a were nominally 1.3 x 1.3 x 7.6 cm (approx.36 g each), bars of ATM-1b were nominally 2 x 2.5 x 17.5 cm (approx.190 g each) and bars of ATM-1c were nominally 1.9 x 1.9 x 15 cm (approx.170 g each). Thirteen bars of ATM-1a, 14 bars of ATM-1b, and 6 bars of ATM-1c were produced. Twelve random samples from each of lots ATM-1a, ATM-1b, and ATM-1c were analyzed. The concentrations (except for U and Cs) were obtained by Inductively-Coupled Argon Plasma Atomic Emission Spectroscopy analysis. Cesium analysis was performed by Atomic Absorption Spectroscopy, while uranium was analyzed by Pulsed Laser Fluorometry. X-ray diffraction analysis of four samples indicated that lot ATM-1a had no detectable crystalline phases (<3 wt %), while ATM-1b and ATM-1c contained approx.3 to 5 wt % iron-chrome spinel crystals. These concentrations of secondary spinel component are not considered uncommon. Scanning electron microscopy examination of fracture surfaces revealed only a random, apparently crystalline, second phase (1-10 ..mu..m diam) and a random distribution of small voids or bubbles (approx.1 ..mu..m nominal diam).
Date: October 1, 1985
Creator: Wald, J.W.
Partner: UNT Libraries Government Documents Department

Unsaturated zone characterization of the Area 5 Radioactive Waste Management Site

Description: Six undisturbed soil samples of near-surface sediments were collected from the Nevada Test Site (NTS) Radioactive Waste Management Site (RWMS) for physical and hydrologic characterization in the laboratory. Of these samples, three were obtained from the wall of Pit No. 3 and three from the floor. Physical properties measured on all samples were dry bulk density ({rho}{sub b}) and solid particle density ({rho}{sub s}). Average dry bulk densities for the wall and floor samples were 1.47 g/cm{sup 3} and 1.45 g/cm{sup 3}, while solid particle densities were 2.34 g/cc and 2.53 g/cc, respectively. Based on these values, the average porosity for the wall samples was computed to be 0.372 and for the floor samples, 0.427. Moisture content-pressure head relations for each sample were determined using the pressure plate method. The moisture characteristic curves generated from these data have shapes similar to those of a silty sand, with volumetric moisture contents of less than 7% at 33.4 bars. Unsaturated hydraulic conductivity was estimated using the computer model of van Genuchten (1978), which is based on the theoretical developments of Mualem (1976). Results indicate that at near-surface in situ moisture contents, the unsaturated hydraulic conductivity for both wall and floor samples is less than 10{sup {minus}8} cm/sec. 15 refs., 12 figs., 4 tabs.
Date: November 1, 1990
Creator: Daffern, D.D.; Ebeling, L.L. & Cox, W.B.
Partner: UNT Libraries Government Documents Department

Influence of changing particle structure on the rate of gas-solid gasification reactions. Final report, July 1981-March 1984

Description: The objetive of this work is to determine the changes in the particle structure of coal as it undergoes the carbon/carbon dioxide reaction (C + CO/sub 2/ ..-->.. 2CO). Char was produced by heating the coal at a rate of 25/sup 0/C/min to the reaction temperatures of 800/sup 0/C, 900/sup 0/C, 1000/sup 0/C and 1100/sup 0/C. The changes in surface area and effective diffusivity as a result of devolitization were determined. Changes in effective diffusivity and surface area as a function of conversion have been measured for reactions conducted at 800, 900, 1000 and 1100/sup 0/C for Wyodak coal char. The surface areas exhibit a maximum as a function of conversion in all cases. For the reaction at 1000/sup 0/C the maximum in surface area is greater than the maxima determined at all other reaction temperatures. Thermogravimetric rate data were obtained for five coal chars; Wyodak, Wilcox, Cimmeron, Illinois number 6 and Pittsburgh number 6 over the temperature range 800-1100/sup 0/C. All coal chars exhibit a maximum in reaction rate. Five different models for gas-solid reactions were evaluated. The Bhatia/Perlmutter model seems to best represent the data. 129 references, 67 figures, 37 tables.
Date: April 4, 1984
Partner: UNT Libraries Government Documents Department

Alternative waste forms for immobilization of transuranic wastes

Description: Several alternative waste forms are being considered for the immobilization of consolidated trnsuranic (TRU) wastes. General characteristics and applicability of these waste forms to TRU wastes are reviewed. Specific attention is given to recent experimental results on sintered ceramic TRU waste forms including bulk properties, impact resistance, leachability, and volatility.
Date: September 1, 1979
Creator: Rusin, J. M. & Palmer, C. R.
Partner: UNT Libraries Government Documents Department

Review of high-level waste form properties. [146 bibliographies]

Description: This report is a review of waste form options for the immobilization of high-level-liquid wastes from the nuclear fuel cycle. This review covers the status of international research and development on waste forms as of May 1979. Although the emphasis in this report is on waste form properties, process parameters are discussed where they may affect final waste form properties. A summary table is provided listing properties of various nuclear waste form options. It is concluded that proposed waste forms have properties falling within a relatively narrow range. In regard to crystalline versus glass waste forms, the conclusion is that either glass of crystalline materials can be shown to have some advantage when a single property is considered; however, at this date no single waste form offers optimum properties over the entire range of characteristics investigated. A long-term effort has been applied to the development of glass and calcine waste forms. Several additional waste forms have enough promise to warrant continued research and development to bring their state of development up to that of glass and calcine. Synthetic minerals, the multibarrier approach with coated particles in a metal matrix, and high pressure-high temperature ceramics offer potential advantages and need further study. Although this report discusses waste form properties, the total waste management system should be considered in the final selection of a waste form option. Canister design, canister materials, overpacks, engineered barriers, and repository characteristics, as well as the waste form, affect the overall performance of a waste management system. These parameters were not considered in this comparison.
Date: December 1, 1980
Creator: Rusin, J.M.
Partner: UNT Libraries Government Documents Department

Physical and chemical characteristics of candidate wastes for tailored ceramics

Description: Tailored Ceramics offer a potential alternative to glass as an immobilization form for nuclear waste disposal. The form is applicable to the wide variety of existing wastes and may be tailored to suit the diverse environments being considered as disposal sites. Consideration of any waste product form, however, require extensive knowledge of the waste to be incorporated. A varity of waste types are under consideration for incorporation into a Tailored Ceramic form. This report integrates and summarizes chemical and physical characteristics of the candidate wastes. Included here are data on Savannah River Purex Process waste; Hanford bismuth phosphate, uranium recovery, redox, Purex, evaporator and residual liquid wastes; Idaho Falls calcine; Nuclear Fuel Services Purex and Thorex wastes and miscellaneous waste including estimated waste stream compositions produced by possible future commercial fuel reprocessing.
Date: December 15, 1980
Creator: Mitchell, M.E.
Partner: UNT Libraries Government Documents Department

Comparative Waste Forms Study

Description: A number of alternative process and waste form options exist for the immobilization of nuclear wastes. Although data exists on the characterization of these alternative waste forms, a straightforward comparison of product properties is difficult, due to the lack of standardized testing procedures. The characterization study described in this report involved the application of the same volatility, mechanical strength and leach tests to ten alternative waste forms, to assess product durability. Bulk property, phase analysis and microstructural examination of the simulated products, whose waste loading varied from 5% to 100% was also conducted. The specific waste forms investigated were as follows: Cold Pressed and Sintered PW-9 Calcine; Hot Pressed PW-9 Calcine; Hot Isostatic Pressed PW-9 Calcine; Cold Pressed and Sintered SPC-5B Supercalcine; Hot Isostatic pressed SPC-5B Supercalcine; Sintered PW-9 and 50% Glass Frit; Glass 76-68; Celsian Glass Ceramic; Type II Portland Cement and 10% PW-9 Calcine; and Type II Portland Cement and 10% SPC-5B Supercalcine. Bulk property data were used to calculate and compare the relative quantities of waste form volume produced at a spent fuel processing rate of 5 metric ton uranium/day. This quantity ranged from 3173 L/day (5280 Kg/day) for 10% SPC-5B supercalcine in cement to 83 L/day (294 Kg/day) for 100% calcine. Mechanical strength, volatility, and leach resistance tests provide data related to waste form durability. Glass, glass-ceramic and supercalcine ranked high in waste form durability where as the 100% PW-9 calcine ranked low. All other materials ranked between these two groupings.
Date: December 1980
Creator: Wald, J. W.; Lokken, R. O.; Shade, J. W. & Rusin, J. M.
Partner: UNT Libraries Government Documents Department

Birch's law and the properties of high temperature fluid metals

Description: By comparing acoustic velocities in fluid metals over a very wide range of densities we have established Birch's Law as an approximate representation over the entire liquid range. For a given liquid metal the acoustic velocity is close to linear in density, with a slope determined by the atomic weight. The measurements include isobaric expansion to less than half normal density, ultrasonics on molten metals at 1 atmosphere, and shock-melted metals to greater than twice normal density. We also find unusual behavior of the Gruneisen gamma, which can be explained in terms of simple fluid models. 15 refs.
Date: January 1, 1987
Creator: Shaner, J.W.
Partner: UNT Libraries Government Documents Department