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Energy R and D in Germany

Description: Germany's total national (i.e., combined public and private sector) funding for R&D stood at $42 billion in 1997. The private sector accounted for nearly 62% ($24 billion) of the total, while the public sector accounted for approximately 38%. Since the late 1970s, when the public and private sectors each funded roughly half of Germany's R&D, the private sector has steadily assumed a larger and larger role as the dominant supporter of R&D activity, while overall government funding has remained essentially flat for much of the past two decades. In addition to declining relative to private R&D expenditures, public R&D expenditures in Germany declined by 4% in real terms between 1991 and 1997, to approximately $15 billion. The reduction in R&D investments in the public sector can be attributed in large part to the financial challenges associated with German reunification and related shifts in social priorities including efforts to address high unemployment and to rebuild basic infrastructure in the eastern states. R&D expenditures have also declined as a percentage of the total public budget, from a peak of 3.4% in 1985 to 2.7% in 1996. Energy R&D has been the hardest hit of all major socioeconomic areas of R&D expenditure funded by the German government. Between 1981 and 1997, public energy R&D fell from approximately $1.6 billion to $400 million--a 75% real decline. The $850 million reduction in Germany's fission R&D budget (which constituted two-thirds of government R&D investment in 1985) explains some 90% of the funding decline. Negative public perceptions regarding the safety and environmental impacts of nuclear energy have reduced nuclear power's viability as a long-term energy option for Germany. Discussions of a complete nuclear phaseout are now under way. At the same time, the German government has slashed its investments in fossil energy R&D by more than 90%. ...
Date: November 1, 1999
Creator: Runci, PJ
Partner: UNT Libraries Government Documents Department

Radioxenons: Their role in monitoring a Comprehensive Test Ban Treaty

Description: Monitoring for xenon radionuclides which are produced in a nuclear detonation can provide a strong deterrent to the violation of a Comprehensive nuclear Test Ban Treaty (CTBT). There are 18 known radioactive xenon isotopes produced in nuclear fission with half-lives ranging from less than one second to 11.9 days. However, only four of these remain in significant amounts more than a day after a detonation. In order for radioxenon monitoring to be practical, it was necessary to develop an automated measurement system which could operate unattended for periods of months, measure the entire spectrum of radioxenons, and provide hundreds of times better sensitivities than current laboratory procedures. This capability was developed at the US Department of Energy`s Pacific Northwest National Laboratory based on rapid separation of atmospheric xenon coupled with a unique high sensitivity measurement device for the radioxenons. A fieldable prototype analyzer is scheduled for testing in August 1996 with commercial availability planned by 1998.
Date: June 1996
Creator: Perkins, R. W. & Casey, L. A.
Partner: UNT Libraries Government Documents Department

Feasibility Study of Using High-Temperature Raman Spectroscopy for On-Line Monitoring and Product Control of the Glass Vitrification Process

Description: A pulse-gating Raman spectroscopy setup was developed in this project. The setup was capable of performing in-situ high-temperature Raman measurements for glasses at temperatures as high as 1412 C. In the literature, high-temperature Raman measurements have only been performed on thin films of glass to minimize black-body radiation effects. The pulse-gating Raman setup allows making high-temperature measurements for bulk melts while effectively minimizing black-body radiation effects. A good correlation was found between certain Raman characteristic parameters and glass melt temperature for sodium silicate glasses measured in this project. Comparisons were made between the high-temperature Raman data from this study and literature data. The results suggest that an optimization of the pulse-gating Raman setup is necessary to further improve data quality (i.e., to obtain data with a higher signal-to-noise ratio). An W confocal Raman microspectrometer with continuous wave laser excitation using a 325 nm excitation line was evaluated selectively using a transparent silicate glass ad a deep-colored high-level waste glass in a bulk quantity. The data were successfully collected at temperatures as high as approximately 1500 C. The results demonstrated that the UV excitation line can be used for high-temperature Raman measurements of molten glasses without black-body radiation interference from the melt for both transparent and deep-color glasses. Further studies are needed to select the best laser system that can be used to develop high-temperature Raman glass databases.
Date: January 4, 1999
Creator: Windisch, C.F. Jr.; Piepel, G.F.; Li, H.; Elliott, M.L. & Su, Y.
Partner: UNT Libraries Government Documents Department

TWRS privatization support project waste characterization resource dictionary

Description: A single estimate of waste characteristics for each underground storage tanks at the Hanford Site is not available. The information that is available was developed for specific programmatic objectives and varies in format and level of descriptive detail, depending on the intended application. This dictionary reflects an attempt to define what waste characterization information is available. It shows the relationship between the identified resource and the original data source and the inter-relationships among the resources; it also provides a brief description of each resource. Developed as a general dictionary for waste characterization information, this document is intended to make the user aware of potenially useful resources.
Date: September 1, 1996
Creator: Patello, G.K. & Wiemers, K.D.
Partner: UNT Libraries Government Documents Department

Summary of uncertainty estimation results for Hanford tank chemical and radionuclide inventories

Description: The exact physical and chemical nature of 55 million gallons of radioactive waste held in 177 underground waste tanks at the Hanford Site is not known in sufficient detail to support safety, retrieval, and immobilization missions. The Hanford Engineering Analysis Best-Basis team has made point estimates of the inventories in each tank. The purpose of this study is to estimate probability distributions for each of the analytes and tanks for which the Hanford Best-Basis team has made point estimates. Uncertainty intervals can then be calculated for the Best-Basis inventories and should facilitate the cleanup missions. The methodology used to generate the results published in the Tank Characterization Database (TCD) and summarized in this paper is based on scientific principles, sound technical knowledge of the realities associated with the Hanford waste tanks, the chemical analysis of actual samples from the tanks, the Hanford Best-Basic research, and historical data records. The methodology builds on research conducted by Pacific Northwest National Laboratory (PNNL) over the last few years. Appendix A of this report summarizes the results of the study. The full set of results (in percentiles, 1--99) is available through the TCD, (http://twins.pnl.gov:8001).
Date: September 1, 1998
Creator: Ferryman, T.A.; Amidan, B.G. & Chen, G.
Partner: UNT Libraries Government Documents Department

Corrosion of mild steel in simulated cesium elution process solutions

Description: The West Valley Support Project is being conducted to meet technology needs for the West Valley Demonstration Project and to provide support to the site cleanup and stabilization activities, which involves removing residual Cs in Tank 8D-1 after waste retrieval. In-tank oxalic acid elution of Cs-loaded zeolite is being evaluated. The work reported here involved evaluating the potential for increased corrosion of Tank 8D-1 during Cs elution, because oxalic acid is corrosive to carbon steel. This included corrosion tests with mild steel (A516 Grade 55) at 27-50 C with 4 and 8 wt% oxalic acid, for 2, 4, and 6 days. Results agreed with Sept. 1995 tests at 50 C for 1-3 weeks. Corrosion rate of A516 Grade 55 mild steel in oxalic acid is quite high (about 150 mils/y or 3.8 mm/y). Corrosion increased three- or fourfold going from 27 to 50 C. Although the tests resulted in a very rough surface appearance, indicating potential for localized corrosion, eg, pitting and crevice corrosion, the exposure times used were apparently too short to initiate pitting.
Date: September 1, 1996
Creator: Elmore, M.R.
Partner: UNT Libraries Government Documents Department

Hanford Site National Environmental Policy Act (NEPA) characterization. Revision 8

Description: This eighth revision of the Hanford Site National Environmental Policy Act (NEPA) Characterization presents current environmental data regarding the Hanford Site and its immediate environs. This information is intended for use in preparing Chapters 4 and 6 in Hanford Site-related NEPA documents. Chapter 4 (Affected Environment) includes information on climate and meteorology, geology, hydrology, ecology, historical, archaeological and cultural resources, socioeconomics, and noise. Chapter 6 (Statutory and Regulatory Requirements) provides the preparer with the federal and state regulations, DOE directives and permits, and environmental standards directly applicable to the NEPA documents on the Hanford Site. The following sections were updated in this revision: climate and meteorology; ecology (threatened and endangered species section only); historical; archaeological and cultural resources; and all of chapter 6. No conclusions or recommendations are given in this report. Rather, it is a compilation of information on the Hanford Site environment that can be used directly by Site contractors. This information can also be used by any interested individual seeking baseline data on the hanford Site and its past activities by which to evaluate projected activities and their impacts.
Date: August 1, 1996
Creator: Neitzel, D.A.; Bjornstad, B.N.; Fosmire, C.J. & Fowler, R.A.
Partner: UNT Libraries Government Documents Department

Institutional Plan FY 1999-2003

Description: Computational science is becoming an increasingly important component of Pacific Northwest's support to DOE's major missions. The advanced parallel computing systems in the William R. Wiley Environmental Molecular Sciences Laboratory (EMSL), coupled with new modeling and simulation software, data management tools, and user interfaces, are providing solutions to previously intractable problems. Research focuses on developing software and other tools to address computational challenges in molecular science, environmental management, global climate change, advanced materials and manufacturing processes, molecular biology, and information management. The Graphics and Visualization Laboratory is part of EMSL'S Molecular Science Computing Facility (MSCF). The MSCF contains a 512-processor IBM RISC System/6000 scalable power parallel computer system that provides the advanced computing capability needed to address ''Grand Challenge'' environmental research problems. The MSCF provides an integrated computing environment with links to facilities in the DOE complex, universities, and industry. The image inserts are graphical representations of simulations performed with software developed at the Laboratory.
Date: February 8, 1999
Creator: Hughes, P.J.
Partner: UNT Libraries Government Documents Department

Electrically switched cesium ion exchange. FY 1996 annual report

Description: An electrochemical method for metal ion separations, called Electrically Switched Ion Exchange, is described. Direct oxidation and reduction of an electroactive film attached to an electrode surface is used to load and unload the film with alkali metal cations. The electroactive films under investigation are Ni hexacyanoferrates, which are deposited on the surface by applying an anodic potential to a Ni electrode in a solution containing the ferricyanide anion. Reported film preparation procedures were modified to produce films with improved capacity and stability. Electrochemical behavior of the derivatized electrodes were investigated using cyclic voltammetry and chronocoulometry. The films show selectivity for Cs in concentrated sodium solutions. Raman spectroscopy was used to monitor changes in oxidation state of the film and imaging experiments have demonstrated that the redox reactions are spatially homogenous across the film. Requirements for a bench scale unit were identified.
Date: December 1, 1996
Creator: Lilga, M.A.; Orth, R.J.; Sukamto, J.P.H.; Schwartz, D.T.; Haight, S.M. & Genders, D.
Partner: UNT Libraries Government Documents Department

Drying results of K-Basin fuel element 0309M (Run 3)

Description: An N-Reactor outer fuel element that had been stored underwater in the Hanford 100 Area K-West Basin was subjected to a combination of low- and high-temperature vacuum drying treatments. These studies are part of a series of tests being conducted by Pacific Northwest National Laboratory on the drying behavior of spent nuclear fuel elements removed from both the K-West and K-East Basins. The drying test series was designed to test fuel elements that ranged from intact to severely damaged. The fuel element discussed in this report was removed from K-West canister 0309M during the second fuel selection campaign, conducted in 1996, and has remained in wet storage in the Postirradiation Testing Laboratory (PTL, 327 Building) since that time. The fuel element was broken in two pieces, with a relatively clean fracture, and the larger piece was tested. A gray/white coating was observed. This was the first test of a damaged fuel element in the furnace. K-West canisters can hold up to seven complete fuel assemblies, but, for purposes of this report, the element tested here is designated as Element 0309M. Element 0309M was subjected to drying processes based on those proposed under the Integrated Process Strategy, which included a hot drying step.
Date: July 1, 1998
Creator: Oliver, B.M.; Klinger, G.S.; Abrefah, J.; Marschman, S.C.; MacFarlan, P.J. & Ritter, G.A.
Partner: UNT Libraries Government Documents Department

Screening assessment and requirements for a comprehensive assessment: Volume 1, Draft. Columbia River comprehensive impact assessment

Description: To evaluate the impact to the Columbia River from the Hanford Site-derived contaminants, the U.S. Department of Energy, U.S. Environmental Protection Agency, and Washington State Department of Ecology initiated a study referred to as the Columbia River Comprehensive Impact Assessment (CRCIA). To address concerns about the scope and direction of CRCIA as well as enhance regulator, tribal, stockholder, and public involvement, the CRCIA Management Team was formed in August 1995. The Team agreed to conduct CRCIA using a phased approach. The initial phase, includes two components: 1) a screening assessment to evaluate the potential impact to the river, resulting from current levels of Hanford-derived contaminants in order to support decisions on Interim Remedial Measures, and 2) a definition of the essential work remaining to provide an acceptable comprehensive river impact assessment. The screening assessment is described in Part I of this report. The essential work remaining is Part II of this report. The objective of the screening assessment is to identify areas where the greatest potential exists for adverse effects on humans or the environment. Part I of this report discusses the scope, technical approach, and results of the screening assessment. Part II defines a new paradigm for predecisional participation by those affected by Hanford cleanup decisions.
Date: April 1, 1997
Partner: UNT Libraries Government Documents Department

Structure/function studies of resorcinol-formaldehyde (R-F) and phenol-formaldehyde (P-F) copolymer ion-exchange resins

Description: he U.S. Department of Energy`s (DOE) Hanford Site was established to produce plutonium for the U.S. defense mission. Over the course of decades, hazardous, toxic, and radioactive chemical wastes were generated and disposed of in a variety of ways including storage in underground tanks. An estimated 180 million tons of high-level radioactive wastes are stored in 177 underground storage tanks. During production of fissile plutonium, large quantities of 90Sr and 137CS were produced. The high abundance and intermediate length half- lives of these fission products are the reason that effort is directed toward selective removal of these radionuclides from the bulk waste stream before final tank waste disposal is effected. Economically, it is desirable to remove the highly radioactive fraction of the tank waste for vitrification. Ion-exchange technology is being evaluated for removing cesium from Hanford Site waste tanks. This report summarizes data and analysis performed by Pacific Northwest National Laboratory (PNNL)for both resorcinol-formaldehyde (R-F) and phenol-formaldehyde (P-F) resins and relates their observed differences in performance and chemical stability to their structure. The experimental approach used to characterize the resins was conducted using primarily two types of data: batch distribution coefficients (Kds) and solid-state 13C NMR. Comparison of these data for a particular resin allowed correlation of resin performance to resin structure. Additional characterization techniques included solid-state 19F NMR, and elemental analyses.
Date: September 1, 1996
Creator: Hubler, T.L.; Franz, J.A.; Shaw, W.J.; Hogan, M.O.; Hallen, R.T.; Brown, G.N. et al.
Partner: UNT Libraries Government Documents Department

Legal and social concerns to the development of bioremediation technologies

Description: The social and legal framework within which bioremediation technologies must be researched, developed, and deployed in the US are discussed in this report. Discussions focus on policies, laws and regulations, intellectual property, technology transfer, and stakeholder concerns. These discussions are intended to help program managers, scientists and engineers understand the social and legal framework within which they work, and be cognizant of relevant issues that must be navigated during bioremediation technology research, development, and deployment activities. While this report focuses on the legal and social environment within which the DOE operates, the laws, regulations and social processes could apply to DoD and other sites nationwide. This report identifies specific issues related to bioremediation technologies, including those involving the use of plants; native, naturally occurring microbes; non-native, naturally occurring microbes; genetically engineered organisms; and microbial products (e.g., enzymes, surfactants, chelating compounds). It considers issues that fall within the following general categories: US biotechnology policy and the regulation of field releases of organisms; US environmental laws and waste cleanup regulations; intellectual property and patenting issues; technology transfer procedures for commercializing technology developed through government-funded research; stakeholder concerns about bioremediation proposals; and methods for assuring public involvement in technology development and deployment.
Date: September 1, 1996
Creator: Bilyard, G.R.; McCabe, G.H.; White, K.A.; Gajewski, S.W.; Hendrickson, P.L.; Jaksch, J.A. et al.
Partner: UNT Libraries Government Documents Department

Performance and evaluation of gas-engine-driven split-system cooling equipment at the Willow Grove Naval Air Station

Description: DOE`s Federal Energy Management Program supports efforts to reduce energy use and associated expenditures within the federal sector; one such effort, the New Technology Demonstration Program (NTDP)(formerly the Test Bed Demonstration program), seeks to evaluate new energy saving US technologies and secure their more timely adoption by the federal government. This report describes the field evaluation conducted to examine the performance of a 15-ton natural-gas-engine- driven, split-system, air-conditioning unit. The unit was installed at a multiple-use building at Willow Grove Naval Air Station, a regular and reserve training facility north of Philadelphia, and its performance was monitored under the NTDP.
Date: January 1, 1997
Creator: Armstrong, P.R. & Schmelzer, J.R.
Partner: UNT Libraries Government Documents Department

Fiscal year 1996 laboratory scale studies of the WVNS flowsheet for remediation of Tank 8D-1 and Tank 8D-2

Description: These tests simulated the West Valley (WV) tank heel removal flowsheet in which oxalic acid solution (OAS) is used to elute Cs from zeolite in tank 8D-1 for 28 h. The eluent is then transferred to tank 8D-2, to dissolve the waste sludge heel. Sequence for the tests were: elute 10 g of Cs-loaded zeolite for 28 h at 50 C at 40 L/kg- zeolite, using 8 wt% OAS; decant used OAS and add 240 g waste slurry simulant, which was washed to <2g/L dissolved solids and containing 120-140 g total oxides/L; let the 3 test combinations (various Fe{sub 2}O{sub 3}) and control age at 50 C for 50 h; and after adjusting pH from 2.5 to 5, sampling at 0.25 to 16 h. Results include visual and analyses; data tables include compositions of the OAS after the Cs- zeolite contact, Cs eluted, supernate OAS in contact with sludge, and neutralized tests. Data have also been graphed for each element vs contact time. Cs elution data was consistent with >90% eluted; the OA conc. after Cs elution was also consistent with essentially no acid consumption. During contact with OAS at pH 2.5, the solution appears to have come into equilibrium with the sludge solid almost immediately; presence of additional Fe oxide appears to have decreased the Cr/Ni/Mn relative solubility. After neutralization, elements that form more insoluble hydroxides such as Fe, Ni, Mn, Ca, and Sr show lower conc. in supernatant; Si may also have been removed. Flowsheet testing confirms that OA is efficient for eluting Cs from zeolite and promotes dissolution of sludge heels in the WV tanks.
Date: November 1, 1996
Creator: Smith, H.D.; Smith, G.L.; Russell, R.L. & Patello, G.K.
Partner: UNT Libraries Government Documents Department

Tank Vapor Characterization Project: Annual status report for FY 1996

Description: In Fiscal Year 1996, staff at the Vapor Analytical Laboratory at Pacific Northwest National Laboratory performed work in support of characterizing the vapor composition of the headspaces of radioactive waste tanks at the Hanford Site. Work performed included support for technical issues and sampling methodologies, upgrades for analytical equipment, analytical method development, preparation of unexposed samples, analyses of tank headspaces samples, preparation of data reports, and operation of the tank vapor database. Progress made in FY 1996 included completion and issuance of 50 analytical data reports. A sampling system comparison study was initiated and completed during the fiscal year. The comparison study involved the vapor sampling system (VSS), a truck-based system, and the in situ vapor sampling system (ISVS), a cart-based system. Samples collected during the study were characterized for inorganic, permanent gases, total non-methane organic compounds and organic speciation by SUMMA{trademark} and TST methods. The study showed comparable sampling results between the systems resulting in the program switching from the VSS to the less expensive ISVS methodology in late May 1996. A temporal study was initiated in January 1996 in order to understand the influences seasonal temperatures changes have on the vapors in the headspace of Hanford waste tanks. A holding time study was initiated in the fourth quarter of FY 1996. Samples were collected from tank S-102 and rushed to the laboratory for time zero analysis. Additional samples will be analyzed at 1, 2, 4, 8, 16, and 32 weeks.
Date: January 1, 1997
Creator: Silvers, K.L.; Fruchter, J.S.; Huckaby, J.L.; Almeida, T.L.; Evans, J.C. Jr.; Pool, K.H. et al.
Partner: UNT Libraries Government Documents Department

Advanced process development for high reflector coatings on solar concentrator panels. Final letter report

Description: Objectives were to develop and demonstrate the manufacturing process for vacuum deposition of low-cost thin-film high reflectance coatings onto large solar concentrator panels; demonstrate thin-film deposition processes for commercialization of this technology by United Solar Technologies (UST); apply reflective coatings to solar concentrator panels for prototype application by UST.
Date: October 1, 1996
Creator: Martin, P.M.; Stewart, C.D.; Bennett, W.D. & Johnston, J.W.
Partner: UNT Libraries Government Documents Department

System design description for the whole element furnace testing system

Description: This document provides a detailed description of the Hanford Spent Nuclear Fuel (SNF) Whole Element Furnace Testing System located in the Postirradiation Testing Laboratory G-Cell (327 Building). Equipment specifications, system schematics, general operating modes, maintenance and calibration requirements, and other supporting information are provided in this document. This system was developed for performing cold vacuum drying and hot vacuum drying testing of whole N-Reactor fuel elements, which were sampled from the 105-K East and K West Basins. The proposed drying processes are intended to allow dry storage of the SNF for long periods of time. The furnace testing system is used to evaluate these processes by simulating drying sequences with a single fuel element and measuring key system parameters such as internal pressures, temperatures, moisture levels, and off-gas composition.
Date: May 1, 1998
Creator: Ritter, G.A.; Marschman, S.C.; MacFarlan, P.J. & King, D.A.
Partner: UNT Libraries Government Documents Department

Low-temperature catalytic gasification of food processing wastes. 1995 topical report

Description: The catalytic gasification system described in this report has undergone continuing development and refining work at Pacific Northwest National Laboratory (PNNL) for over 16 years. The original experiments, performed for the Gas Research Institute, were aimed at developing kinetics information for steam gasification of biomass in the presence of catalysts. From the fundamental research evolved the concept of a pressurized, catalytic gasification system for converting wet biomass feedstocks to fuel gas. Extensive batch reactor testing and limited continuous stirred-tank reactor tests provided useful design information for evaluating the preliminary economics of the process. This report is a follow-on to previous interim reports which reviewed the results of the studies conducted with batch and continuous-feed reactor systems from 1989 to 1994, including much work with food processing wastes. The discussion here provides details of experiments on food processing waste feedstock materials, exclusively, that were conducted in batch and continuous- flow reactors.
Date: August 1, 1996
Creator: Elliott, D.C. & Hart, T.R.
Partner: UNT Libraries Government Documents Department

Independent Evaluation of Air Filter Media from Chornobyl

Description: An independent evaluation was performed to assess the morphology, pressure drop characteristics, alpha spectroscopy characteristics, and collection efficiency of an air sampling filter media and two types of aerosol face masks provided from Chernobyl by Pacific Northwest National Laboratory. The evaluation included characterizing the filter morphology by scqg electron microscopy; measuring the filter pressure drop as a function of air flowrate; evaluating the spectroscopy characteristics of the filter for alpha-emitting radionuclides by sampling ambient radon progeny aerosols in an Eberline Alpha-6A alpha continuous air monitor; determining the particle collection efficiency of the filter media for 0.3 {micro}m aerodynamic diameter monodisperse particles at 1 and 2 cfm; and comparing the apparent construction, durability, and performance similarities of the filter media to other media commonly used for monitoring airborne alpha-emitting radionuclides.
Date: December 21, 1999
Creator: Hoover, MD; Fencl, AF & Vargo, GJ
Partner: UNT Libraries Government Documents Department

Effects of High-pH and High-Ionic-Strength Groundwater on Iodide, Pertechnetate, and Selenate Sorption to Hanford Sediments: Final Report for Subtask 3a

Description: As part of the Immobilized Low-Activity Waste-Performance Assessment three experiments were conducted to evaluate the effect of the expected near-field chemistry on the sorption of iodide, selenate, and pertechnetate onto a sediment obtained from the Hanford Site. These experiments were performed in fiscal year 1998 at the Pacific Northwest National Laboratory.' During these experiments, attention was directed at the identification of the chemical mechanisms controlling the sorption processes to provide technical defensibility for the selection of the distribution coefficients (IQ to be used in the remainder of the performance assessment. It was found, during the conduct of the experiments, that selenium and technetium I&s increased as ionic strength increased. The cause for this is most likely to be that the higher ionic strength caused the double layer around the particles to decrease, thereby permitting greater interaction with the mineral surfaces. Further, the pH level had an effect on the sorption of these anions. These are the first-ever experiments conducted with Hanford Site sediment in which the IQ were measured as a function of ionic strength and pH. Overall, the observed trends were consistent with more generalized geochemical principles. One of the most important contributions of these experiments was that they quantified the & changes induced by variations in ionic strength and pH that are expected to exist in the near field.
Date: October 14, 1998
Creator: Kaplan, DI; Parker, KE & Orr, RD
Partner: UNT Libraries Government Documents Department

Evaluation of the Long-Term Performance of Titanate Ceramics for Immobilization of Excess Weapons Plutonium: Results from Pressurized Unsaturated Flow and Single Pass Flow-Through Testing

Description: This report summarizes our findings from pressurized unsaturated flow (PUF) and single-pass flow-through (SPFT) experiments to date. Results from the PUF test of a Pu-bearing ceramic with enclosing surrogate high-level waste glass show that the glass reacts rapidly to alteration products. Glass reaction causes variations in the solution pH in contact with the ceramic materials. We also document variable concentrations of Pu in solution, primarily in colloidal form, which appear to be related to secular variations in solution composition. The apparent dissolution rate of the ceramic waste form, based on Ba concentrations in the effluent, is estimated at {le} 10{sup {minus}5} g/(m{sup 2} {center_dot} d). Pu-bearing colloids were recovered in the size range of 0.2 to 2 {micro}m, but it is not clear that such entities would be transported in a system that is not advective-flow dominated. Results from SPFT experiments give information on the corrosion resistance of two surrogate Pu-ceramics (Ce-pyrochlore and Ce-zirconolite) at 90 C over a pH range of 2 to 12. The two ceramics were doped with minor quantities ({approximately}0.1 mass%) of MoO{sub 3}, so that concentrations of Mo in the effluent solution could be used to monitor the reaction behavior of the materials. The data obtained thus far from experiments with durations up to 150 d do not conclusively prove that the solid-aqueous solution systems have reached steady-state conditions. Therefore, the dissolution mechanism cannot be determined. Apparent dissolution rates of the two ceramic materials based on Ce, Gd, and Mo concentrations in the effluent solutions from the SPFT are nearly identical and vary between 1.1 to 8.5 x 10{sup {minus}4} g/(m{sup 2} {center_dot} d). In addition, the data reveal a slightly amphoteric dissolution behavior, with a minimum apparent rate at pH = 7 to 8, over the pH range examined. Results from two related ceramic ...
Date: September 13, 1999
Creator: McGrail, B. P.; Schaef, H. T.; Icenhower, J. P.; Martin, P. F.; Orr, R. D. & Legore, V. L.
Partner: UNT Libraries Government Documents Department

Comparison of vapor sampling system (VSS) and in situ vapor sampling (ISVS) methods on Tanks C-107, BY-108, and S-102

Description: The objective of this report is to evaluate the equivalency of two methods used to sample nonradioactive gases and vapors in the Hanford Site high-level waste tank headspaces. In addition to the comparison of the two sampling methods, the effects of an in-line fine particle filter on sampling results are also examined to determine whether results are adversely affected by its presence. This report discusses data from a January 1996 sampling.
Date: May 1, 1996
Creator: Huckaby, J. L.; Edwards, J. A. & Evans, J. C.
Partner: UNT Libraries Government Documents Department