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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 1,405 records · Page 78
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DOE OSTI2015

Novel inorganic sorbent for iodine removal in pump and treat system - 15020

The radioisotope {sup 129}I is one of the key risk components in the migrating subsurface plumes present in the Hanford Site vadose zone due to its long half-life, large inventory, high toxicity, and high mobility in the aquifer. Removal of iodine from groundwater in the 200 Area is an essential component for managing the Hanford Site cleanup and protecting the Columbia River. In the subsurface aquatic environment it mainly exist as iodide, iodate, and organic derivatives of iodine. Because of different chemical properties of these species and significantly lower concentration than other constituents in the subsurface plumes their removal using commercial ion exchange resins is problematic. In addition, availability of a stable matrix for a long-term waste form for iodine is needed. Novel engineered inorganic composites that possess superior characteristics including large surface area, high sorption capacity, and good chemical-mechanical-thermal stability may potentially offer a solution. These two-in-one novel materials can be designed to serve as an efficient sorbent for the simultaneous removal of the dissimilar iodine species and a durable waste form under environmentally relevant conditions. This paper describes our current results on identification, characterization, and testing of the iodine-selective inorganic sorbents. (authors)

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DOE OSTI2015

Benefits from R. and D. for D. and D. projects - 15089

CEA (French Alternative Energies and Atomic Energy Commission) is both the operator of important nuclear facilities all over the nuclear cycle, in charge of major new built or D and D projects and a R and D group with dynamic policy of technology transfer: second in France for patents deposit, active partnership agreements with industries, and support for Start-ups. The position of CEA in D and D is unique because of the number and the wide diversity of facilities under decommissioning, with some high level of contamination. Innovative solutions are being developed in 6 main axes to protect the operators, to minimize the overall costs and the volumes of waste: - Investigations in the facilities - Radiological measurement of waste - Robotics, laser cutting devices, virtual reality to simulate and choose the best way to operate, - Decontamination of soils and structures - Waste treatment and conditioning - Methods and Information Technology (IT)Tools for project and waste management The last developments are shown and examples of industrial applications given: encapsulation of Magnesium or vitrification of high level waste for UP1 retreatment plant, treatment of sodium for Phenix fast breeder, treatment of organic liquids, etc. CEA is willing to share actions in partnership with other operators or with industrials so they can use the results for other contracting authorities. (authors)

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DOE OSTI2015

Improving high level waste solids mobilization and transfer through Hanford double-shell tanks - 15099

The Hanford Tank Operations Contractor (TOC) and the Hanford Waste Treatment and Immobilization Plant (WTP) contractor are both engaged in demonstrating mixing, sampling, and transfer system capabilities using simulated Hanford High-Level Waste (HLW) formulations. Efficient and effective handling of solid radioactive waste is essential to the successful completion of River Protection Project (RPP) mission and the Department of Energy's Hanford site. The TOC ust transfer over 416 million liters (110 million gallons) of HLW slurry through a complex system of 28 double shell tanks (DSTs) of approximately 3.8 million liters (1 million gallons) each as it is staged and delivered to the WTP. Through the use of scaled tanks and non-radioactive simulants, the TOC has identified operational methodologies for mixer pumps that enhance the movement of the solids through the DST system which will minimize the amount of solids remaining for final tank closeout. (authors)

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DOE OSTI2015

Selective separation of Sr by potassium titanates from solution of nitrate - 15248

The radioactive waste treatment is planned in LWTF (Low-level radioactive Waste Treatment Facility, JAEA) for the low-level liquid wastes generated from Tokai-reprocessing facility [1]. The target liquid wastes mainly consist of highly concentrated sodium nitrate (4.7 M NaNO{sub 3}) containing low level radioactive {sup 137}Cs and {sup 90}Sr, while the conventional adsorbent (Titanic acid-PAN) has some problems in the adsorption performance and irradiation resistance. In this study, the adsorption properties of Sr{sup 2+} ions, leaching properties of Sr{sup 2+} and irradiation properties were clarified by using the novel adsorbent of potassium titanates (KT-1). Relatively large uptake percentage (99%) and maximum uptake capacity (0.37 mmol/g) were obtained for the KT-1 compared to that of Titanic acid-PAN. As for the breakthrough properties, KT-1 had the smoother breakthrough carve and larger 5% breakthrough capacity compared to Titanic acid-PAN. From the results of batch and column experiments, KT-1 was effective for the uptake of Sr{sup 2+} ions in the presence of highly concentrated Na{sup +} ions. The leached percentages of Sr{sup 2+} ions form calcined products of Sr-KT-1 in pure water and 0.1 M NaOH were less than the detection limit of ICP-AES, and those in 0.1 M HCl tended to markedly decrease with calcining temperature; the formation of SrTiO{sub 3} phase above 800 deg. deg. C was effective for the lowering of leachability. The irradiation stability of the adsorbent was examined by instrumental analyses and the evaluation for the uptake percentage of Sr{sup 2+} ions by batch method. The growth of surface crystal was observed by SEM, but no significant change in X-ray diffraction peak was observed, and Sr{sup 2+} uptake (%) was almost constant. The novel adsorbent of KT-1 had excellent characteristics for Sr selectivity, uptake capacity, leachability and irradiation resistance. KT-1 is thus effective for the treatment and disposal in LWTF. (authors)

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DOE OSTI2015

Managing the interfaces for successful waste treatment operations at the river protection project - 15347

The Department of Energy (DOE) is constructing the Waste Treatment and Immobilization Plant (WTP) at the Hanford site in Washington to treat and immobilize(vitrify) approximately 432 million liters (114 million gallons) of high level radioactive waste (after all single-shell retrievals are accomplished). The tank operating contractor (TOC) is charged with delivering feed, with preconditioning if required. Other Hanford contractors are charged with providing utilities and other services and waste disposal facilities. In all, four DOE contractors, two DOE offices along with DOE headquarters, and two Washington state regulators play essential roles in enabling successful treatment operations eliminate the radioactive and hazardous waste threats to the public and the environment. DOE has decided that the appropriate approach is to proceed with operations at the WTP's Low-Activity Waste (LAW) vitrification facility ahead of completing the WTP Pretreatment and High Level Waste (HLW) waste vitrification facilities, This paper outlines the approach that is being taken to ensure that all the functions, reviews, and approvals needed for radioactive operations are achieved to allow successful feed delivery, startup, and operations of the WTP in a direct feed to LAW mode. A massive effort is needed to be successful and a One System organization, jointly managed and staffed by WTP and TOC personnel is tasked with achieving the integration, coordination, tracking, and reporting necessary for the endeavor. (authors)

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DOE OSTI2015

Technetium and iodine getters to improve Cast Stone performance - 15420

Technetium-99 ({sup 99}Tc) and iodine-129 ({sup 129}I) have been determined to be tank waste components contributing most to the environmental impacts associated with the cleanup of the Hanford site. Cast Stone, which has the ability to immobilize {sup 99}Tc, {sup 129}I, and other contaminants of concern, is being considered as a low temperature waste form for solidification of aqueous secondary liquid effluents from the Hanford Tank Waste Treatment and Immobilization Plant (WTP) An environmental assessment of Cast Stone performance, using measured diffusivities of the radionuclides from the Cast Stone product, calculates groundwater at the 100 m down-gradient in excess of the allowable maximum permissible concentrations for both radionuclides. Therefore, an opportunity exists to improve the performance of Cast Stone. One method for improvement is through the addition of immobilizing agents known as 'getters' that selectively sequester Tc and I. In the present paper, we report on seven getter materials that have been tested for Tc and five materials that have been tested for I to determine their effectiveness for radionuclide removal in a series of batch sorption tests in 18.2 MΩ DI H{sub 2}O and a 7.8 M Na Ave LAW waste simulant. Contact experiments have been carried out in anoxic conditions at room temperature, with varying solid-to-solution ratios, and in the presence and absence of competing species. Results indicate that most materials perform better in the 18.2 MΩ DI H{sub 2}O compared to the 7.8 M Na LAW waste simulant for both Tc and I getter. Radionuclide sequestration may be affected by the presence of the redox sensitive Cr(VI) in the simulant. The top performing Tc getter materials, Sn(II)-apatite, BFS-2, KMS-2 and Sn-hydroxyapatite, were examined through various solid-state characterization techniques such as SEM/XEDS, XANES and EXAFS. Tc removal is theorized to occur through reduction of the highly soluble Tc(VII) species to the less soluble Tc(IV). Solution results from the series of I tests show that iodide is effectively removed from solution via, most likely, a precipitation reaction of AgI. A wide range of I getter materials and the silver exchanged zeolite getter performed well in both DI water and the simulant. (authors)

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DOE OSTI2015

3D Sonar for tank waste quantification - 15430

An innovative remote 3D Sonar technology adapted from the oil and gas industry has been successfully applied to the mapping of radioactive sludge deposits during tank, fuel pool and silo remediation operations at the Sellafield site in the UK. The technology can: -Measure the disposition and calculate the volume of settled solids in a waste tank thereby supporting tank closure objectives - Produce accurate 3-D images of solids disposition, structure and tank internals to help identify where sludge deposits and debris are located -Capture real time 'Sonar video' of movement of solids in the tank in real time to aid retrieval - Detect and monitor gas release and bubble generation Aside from direct safety, cost and schedule benefits, improved accuracy and confidence in residual waste volume determinations can lead to increased level of regulator confidence in meeting closure objectives. This technology has potential to bring such benefits to challenges in the DOE estate, such as Savannah River Site (SRS) and Hanford Tank Farms remediation, and operations at the Hanford Waste Treatment Plant. This paper describes the 3D Sonar technology and its applications, and reviews a 3D Sonar demonstration project specifically aimed at enhancing retrieval and closure operations at SRS. (authors)

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DOE OSTI2015

The cementitious barriers partnership experimental programs and software advancing DOE's waste disposal/tank closure efforts - 15436

The U.S. Department of Energy Environmental Management (DOE-EM) Office of Tank Waste Management sponsored Cementitious Barriers Partnership (CBP) is chartered with providing the technical basis for implementing cement-based waste forms and radioactive waste containment structures for long-term disposal. DOE needs in this area include the following to support progress in final treatment and disposal of legacy waste and closure of High-Level Waste (HLW) tanks in the DOE complex: - Long-term performance predictions and - Flow sheet development and flow sheet enhancements - Conceptual designs for new disposal facilities The DOE-EM Cementitious Barriers Partnership is producing software and experimental programs resulting in new methods and data needed for end-users involved with environmental cleanup and waste disposal. Both the modeling tools and the experimental data have already benefited the DOE sites in the areas of performance assessments by increasing confidence backed up with modeling support, leaching methods, and transport properties developed for actual DOE materials. In 2014, the CBP Partnership released the CBP Software Toolbox - 'Version 2.0' which provides concrete degradation models for: 1) sulfate attack, 2) carbonation, 3) chloride initiated rebar corrosion, and includes constituent leaching. These models are applicable and can be used by both DOE and the Nuclear Regulatory Commission (NRC) for service life and long-term performance evaluations and predictions of nuclear and radioactive waste containment structures across the DOE complex (Figure 1) including Future SRS salt-stone and HLW tank performance assessments and special analyses - Hanford site HLW tank closure projects and other projects in which cementitious barriers are required - The Advanced Simulation Capability for Environmental Management (ASCEM) project which requires source terms from cementitious containment structures as input to their flow simulations - Regulatory reviews of DOE performance assessments - Nuclear Regulatory Commission reviews of commercial nuclear power plant (NPP) structures which are part of the overall US Energy Security program to extend the service life of NPPs In addition, the CBP experimental programs have had a significant impact on the DOE complex by providing specific data unique to DOE sodium salt wastes at Hanford and SRS which are not readily available in the literature. Two recent experimental programs on cementitious phase characterization and on technetium (Tc) mobility have provided significant conclusions as summarized below: Recent mineralogy characterization discussed in this paper illustrates that sodium salt waste form matrices are somewhat similar to but not the same as those found in blended cement matrices which to date have been used in long-term thermodynamic modeling and contaminant sequestration as a first approximation. Utilizing the CBP generated data in long-term performance predictions provides for a more defensible technical basis in performance evaluations. - In addition, recent experimental studies related to technetium mobility indicate that conventional leaching protocols may not be conservative for direct disposal of Tc- containing waste forms in vadose zone environments. These results have the potential to influence the current Hanford supplemental waste treatment flow sheet and disposal conceptual design. (authors)

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DOE OSTI2015

Analysis of erosion/corrosion data for high-level waste pipelines at Hanford - 15519

Washington River Protection Solutions (WRPS) has implemented a fitness-for-service program which will evaluate the degraded condition of the tank farm waste transfer system. The Tank Farms Waste Transfer System Fitness-for-Service Requirements and Recommendations, includes a requirement to inspect primary piping, encasements, and jumpers for corrosion/erosion. The 242-A Evaporator pump room was upgraded by adding instrumentation to the feed and return jumpers, prior to running the next campaign. As part of this upgrade, several jumpers were removed for disposal and a total of five jumpers were selected for ultrasonic thickness (UT) inspection. The jumpers selected were the following: 18-4, C-4 and 5, J-13A, 13-K, and 19-5. All of these jumpers will be removed permanently except for jumper 19-5 which will be reinstalled for further service. As part of this study, several jumpers from the AW-02E Feed Pit were also removed for disposal and two were selected for UT inspection. The jumpers selected were the 1-4 and B-2 which were packaged and sent to the 222-S Laboratory for UT assessments. This paper includes details of each jumper as well as the estimated remaining useful life (ERUL), if applicable, for its components based on the wall thinning measured in elbows and straight sections. The jumper's ultrasonic thickness measurements are plotted and trends are assessed based on the volume of fluid transferred or time of service. Variability in thickness is generally evaluated in two approaches, radially around the circumference of the pipe or component and longitudinally along the length. The paper also explains the analysis procedure for evaluating the different components. In particular, issues related to thinning from manufacturing different types of elbows (long radius, five diameter bend radius) are presented. Analysis techniques are developed for elbows that differentiate thinning from erosion/corrosion and manufacturing which is critical for this analysis. Results demonstrate that in most components, the thickness measurements are still greater than the manufactured nominal thickness. For the cases in which the thickness is below the nominal thickness, the ERUL well exceeds the life needed for servicing the Waste Treatment Plant. (authors)

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DOE OSTI2015

Materials for Tc capture to increase Tc retention in glass waste form - A review - 15553

{sup 99}Technetium is a long-lived fission product found in the tank waste at the Hanford site in Washington State. In its hepta-valent species, it is volatile at the temperatures used in Hanford Tank Waste Treatment and Immobilization Plant vitrification melters, and thus is challenging to incorporate into waste glass. In order to decrease volatility and thereby increase retention, technetium can be converted into more thermally stable species. Several mineral phases, such as spinel, are able to incorporate tetravalent technetium in a chemically durable and thermally stable lattice, and these hosts may promote the decreased volatility that is desired. In order to be usefully implemented, there must be a synthetic route to these phases that is compatible with both technetium chemistry and current Hanford Tank Waste Treatment and Immobilization Plant design. Synthetic routes for spinel and other potential host phases are examined. (authors)

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DOE OSTI2015

Plan for resolution of technical issues at the Hanford waste treatment and immobilization plant project - 15596

The Waste Treatment and Immobilization Plant (WTP) Project has a number of first-of-a-kind technical challenges that have necessitated expert analysis and testing activities to resolve. Since 2006, the U.S. Department of Energy (DOE) chartered two major WTP technical reviews. Most recently, in 2012, a number of top scientists and engineers conducted a review focused on the design and operability of WTP black cell and hard-to-reach areas. To provide leadership and oversight for resolution of the technical issues, DOE assembled a Design Completion Team composed of personnel from the DOE Office of River Protection (ORP), DOE contractors, and the national laboratories. The Design Completion Team established five technical sub-teams to address specific focus areas. The work of these sub-teams has evolved such that the project is now focused on eight technical issues referred to as T1 to T8. The WTP contractor has developed, and DOE has approved, plans for resolution of these issues. These plans form the basis for the Pretreatment (PT) Facility engineering work that will be performed over the coming years. This work, along with a corresponding update to the PT Facility safety basis, will result in an authorization to resume the engineering work necessary to complete the PT Facility design. (authors)

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DOE OSTI2015

Nuclear waste management approach for new build nuclear power plants in the people's republic of China - 15687

EnergySolutions continues to provide waste treatment solutions in the People's Republic of China (PRC). Currently two projects are in the installation phase at different sites (Haiyang, an AP-1000TM site and Yangjiang, a CPR-1000 site). EnergySolutions is also working closely with PRC nuclear regulatory officials for certification of High Integrity Containers (HIC). This paper discusses progress on these two projects, and new information regarding current and future PRC waste management plans. (authors)

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DOE OSTI2016

U.S. Senate Bill S.854-IS - A Maladjusted Politicized Maze for Consent-Based Siting of New HLW-Repositories - 16019

At the end of 2015, the USA's HLW-disposal program had been on hold since 2010 pending the enactment of enabling legislation for one or both of: 1) The Yucca Mountain HLW repository; and/or 2) The law proposed in Senate Bill S.854-IS 'to establish a new organization to manage nuclear waste, provide a consensual process for siting nuclear waste facilities, ensure adequate funding for managing nuclear waste, and for other purposes'. But, S.854-IS does not acknowledge the existence of the Yucca Mountain HLW repository, which, if re-enabled, would affect both when another HLW repository would be needed and its disposal capacity. Furthermore, it neither timely nor meaningfully integrates waste generators, facility-host(s) and other directly affected parties with the new 'implementing' organizations deemed to be more susceptible to political influence and interferences than those plaguing the Yucca Mountain HLW repository program since 1987 that resulted in a multitude of contentions, lawsuits, delays, and increased costs. For these and other reasons very compelling and conclusive to the author, the legal status of the YM HLW repository should be 'definitive' before a law based upon S.854-IS is enacted. Instead, the near-term focus should be on: 1. Defining 'consent-based' quantitatively. 2. Promptly siting and opening at least one large, expandable, 'consolidated' HLW-storage facility allowing the government to begin taking title to commercially-generated HLW; most-expeditiously accomplished by amending existing legislation. 3. Updating S.854-IS based on lessons learned about siting, developing, and licensing nuclear-waste-storage and -disposal facilities in the USA and abroad the past 30+ years. (authors)

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DOE OSTI2016

Leak Testing with Simulated Waste of Hanford Tank Farm Valves Utilized for Double Valve Isolation - 16108

The existing Hanford Tank Farms Waste Transfer System has several models of ball valves used for double valve isolation (DVI) that have been installed for 10 or more years. The safety function of the safety-significant valves is to limit leakage of waste past the valves in order to decrease the consequences of a fine spray release due to a transfer misroute. While previous leak testing of the valves has been conducted, the testing did not address concerns in the Documented Safety Analysis concerns about the impact on valve operation and service life of the potential abrasive/erosive properties of the tank waste on the valves when cycled. Pacific Northwest National Laboratory (PNNL) conducted DVI tests at their Multi-Phase Transport Evaluation Loop Facility. Testing evaluated the leak rate of safety-significant isolation valves for DVI as a function of simulated operating cycles. PNNL developed a performance-based simulant specifically for this test program. The test environment simulated the abrasive characteristics of the Hanford Tank Farms Waste Transfer System during single-shell tank retrieval and waste feed delivery to the Hanford Tank Waste Treatment and Immobilization Plant. The testing consisted of periodically measuring leak rates and maximum operational torques on the DVI valves after prescribed numbers of valve operational cycles (open and close). The test results from the simulant cycle tests provide Washington River Protection Solutions with performance characteristics that can be used to verify compliance with the Documented Safety Analysis limits for valve seat leakage. (authors)

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DOE OSTI2016

Development of High Alumina Glass Property Data for Hanford High-Level Waste Glass Models - 16231

Roughly half of the projected Hanford high-level waste batches will have waste loadings limited by relatively high concentration of Al{sub 2}O{sub 3}. Individual glasses have been formulated and tested to demonstrate that it is possible to increase the loading of these high-Al{sub 2}O{sub 3} wastes in glass by as much as 50%. To implement such increases in waste loading in the Hanford Tank Waste Treatment and Immobilization Plant, the impact of composition on the properties of high-Al{sub 2}O{sub 3} waste glasses must be quantified in the form of validated glass property-composition models. To collect the data necessary for glass property-composition models, a multi-phase experimental approach was developed. In the first phase of the study, a set of 46 glass compositions were statistically designed to most efficiently backfill existing data in the composition region for high-Al{sub 2}O{sub 3} (15 to 30 wt%) waste glasses. The glasses were fabricated and key glass properties were tested: - Product Consistency Test (PCT) on quench (Q) and canister centerline cooled (CCC) samples - Toxicity Characteristic Leaching Procedure (TCLP) on Q and CCC samples - Crystallinity as a function of temperature (T) at equilibrium and of CCC samples - Viscosity and electrical conductivity as a function of T The measured properties of these glasses were compared to predictions from previously existing models developed over lower Al{sub 2}O{sub 3} concentration ranges. Areas requiring additional testing and modeling were highlighted. (authors)

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DOE OSTI2016

200 West Pump and Treat: The First Three Years - 16473

The 200 West Pump and Treat (P and T), on the U.S. Department of Energy's Hanford Site, has a 9,464 liters per minute capacity designed to capture and treat an 8 km{sup 2} contaminated groundwater plume and reduce the mass of contaminants of concern (COCs) by 95 percent in 25 years. Treatable contaminants include carbon tetrachloride, trichloroethene, chromium, hexavalent chromium, nitrate, iodine-129 (I-129), and technetium-99 (Tc-99). After 3.5 years of continuous operation, the 200 West P and T treated over 10 billion liters of contaminated groundwater and removed over 190,000 kg of nitrate, 9,000 kg of carbon tetrachloride, nearly 5 curies of technetium-99, and smaller quantities of the remaining contaminants. Twenty three extraction wells strategically installed across the plumes pull contamination in from surrounding areas directing contaminated groundwater to the 200 West P and T for treatment. The 200 West P and T successfully removes all contaminants to below cleanup levels which are at (or lower than) the drinking water standard. Twenty one injection wells return treated water to the aquifer providing flow-path control to mitigate migration of contamination toward the Columbia River, a source of drinking water to the communities downstream. Contaminant concentrations in most monitoring wells are declining and the remedy is on target for accomplishing the mass removal goal ahead of schedule. In 2015, the 200 West P and T was expanded to include treatment for uranium from other operable units. With the uranium treatment expansion, the 200 West P and T is capable of cost-effectively treating contaminated groundwater beneath the 194 km{sup 2} Central Plateau. (authors)

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DOE OSTI2016

Testing of New Technetium Selective Media TcTreat - 16497

A new zirconium oxide based material TcTreat is under development and testing for the removal of radioactive oxo-anionic species (Tc-99 pertechnetate, Ru-106 ruthenate) from solution. TcTreat exhibited a very high {sup 99}Tc uptake over a broad pH-range of 4-10 and the uptake was reasonably high also in mildly alkaline and acidic ranges. Nitrate and sulphate had a decreasing effect on {sup 99}Tc uptake but is was still strong (k{sub d} = 100,000 ml/g and above) even at 1 molar concentrations.

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DOE OSTI2016

Reevaluation of Actinide(IV)-Humic Complexation in the WIPP Performance Assessment - 16547

The legacy humic colloid model for tetravalent actinides (Th(IV), U(IV), Np(IV), and Pu(IV)) in the performance assessment (PA) of the Waste Isolation Pilot Plant (WIPP) is highly conservative. The model structure is feasible, but substantial reductions are needed for two constants, PHUMSIM and PHUMCIM. These constants are proportionality constants representing the equilibrium aqueous concentration ratio of humic-bound An(IV) to non-colloidal An(IV) for the Salado and Castile formations. In the WIPP PA model, both constants are set at 6.3 based on observed colloidal partitioning of Th(IV) in seawater. This value greatly enhances the mobile An(IV) concentration in the WIPP PA. Actual humic partitioning of An(IV) in WIPP brines is expected to be significantly lower than in seawater because the pH of WIPP brines (∼9) is higher, concentrations of competing cations (e.g., Mg{sup 2+}) are higher, and concentrations of aqueous humic substances may be lower. In this work, the results of recent studies of Th(IV)-humic and Ca{sup 2+}-humic complexation are used to simulate competitive humic complexation under WIPP conditions. The PHUMSIM and PHUMCIM values calculated for these simulations are in the range of 0.0013-0.0016 and 0.0047-0.0056, respectively. These values reduce humic-bound An(IV) to less than 1% of aqueous non-colloidal concentrations and would reduce mobile An(IV) concentrations in the WIPP PA by as much as 85%. (authors)

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