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At least 235 records · Page 13
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Special Analysis for the Disposal of U.S. Department of Energy High Activity Cesium Sources Waste Stream at the Area 5 Radioactive Waste Management Site, Nevada National Security Site, Nye County, Nevada

This special analysis evaluates whether the Lawrence Livermore National Laboratory (LLNL) U.S. Department of Energy (DOE) High Activity Cesium (Cs) Sources waste stream is suitable for shallow land burial at the Area 5 Radioactive Waste Management Site on the Nevada National Security Site. Disposal of the LLNL DOE High Activity Cs Sources waste meets all DOE M 435.1-1, “Radioactive Waste Management Manual,” Chapter IV, Section P performance objectives (DOE 1999). The LLNL DOE High Activity Cs Sources waste stream is recommended for acceptance with the conditions that 1) the total waste stream cesium-137 activity be limited to 1.7E16 Bq and 2) the waste be disposed 4.4 m (10 ft) below existing grade.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2026

RH-TRU Waste Streams: HFDA Crucibles Create New Complex Waste Stream

This project focuses on the removal of the Hot Fuel Dissolution Apparatus (HFDA) crucibles from the Hot Fuel Examination Facility’s (HFEF) hot cells to create space for upcoming projects. The project team has created a crucible and pyro-salt non-debris waste stream that can be disposed of at Waste Isolation Pilot Plant (WIPP). Chemical Compatibility Examinations (CCEs) must be performed on candidate waste by reviewing the types of chemicals used in the experiments, information found in INL Process Knowledge Summary Reports (PKSRs), and Environmental Protection Agency guides on chemical compatibility. The CCEs identify which chemicals can be safely combined to ensure adverse reactions do not occur in the waste packages. The CCEs are then used to update the PKSR, Basis of Knowledge, and Acceptable Knowledge documents and demonstrate compliance with the WIPP Waste Acceptance Criteria. Once documents are finalized, they are reviewed and approved by the WIPP Central Characterization Project (CCP) to ensure proper waste stream characterization. After the documents are approved, the crucibles can be packaged and shipped to the Idaho Nuclear Technical and Engineering Center for storage awaiting certification. CCP will certify the waste using the approved documents and a series of confirmatory testing before being shipped and disposed in WIPP’s deep geological repository. Currently, the CCE is in progress and the PKSRs are being updated.

Basis of Knowledge↗
DOE OSTI2017

Analysis on carbon dioxide emission reduction during the anaerobic synergetic digestion technology of sludge and kitchen waste: Taking kitchen waste synergetic digestion project in Zhenjiang as an example

Highlights: • Reduce CO{sub 2} emission is a referential index for future sludge disposal. • Synergetic digestion technology of kitchen waste and sludge contributes to the CO{sub 2} reduction. • Synergetic digestion technology reduced more CO{sub 2} emission than sludge landfill. • Synergetic digestion technology should be effectively promoted and applied. - Abstract: With the popularization of municipal sewage treatment facilities, the improvement of sewage treatment efficiency and the deepening degree of sewage treatment, the sludge production of sewage plant has been sharply increased. Carbon emission during the process of municipal sewage treatment and disposal has become one of the important sources of greenhouse gases that cause greenhouse effect. How to reduce carbon dioxide emissions during sewage treatment and disposal process is of great significance for reducing air pollution. Kitchen waste and excess sludge, as two important organic wastes, once uses anaerobic synergetic digestion technology in the treatment process can on the one hand, avoid instability of sludge individual anaerobic digestion, improve sludge degradation rate and marsh gas production rate, and on the other hand, help increase the reduction of carbon dioxide emissions to a great extent. The paper uses material balance method, analyzes and calculates the carbon dioxide emissions from kitchen waste and sludge disposed by the anaerobic synergetic digestion technology, compares the anaerobic synergetic digestion technology with traditional sludge sanitary landfill technology and works out the carbon dioxide emission reductions after synergetic digestion. It takes the kitchen waste and sludge synergetic digestion engineering project of Zhenjiang city in Jiangsu province as an example, makes material balance analysis using concrete data and works out the carbon dioxide daily emission reductions. The paper analyzes the actual situation of emission reduction by comparing the data, and found that the synergetic digestion of kitchen waste and sludge can effectively reduce the carbon dioxide emission, and the reduction is obvious especially compared with that of sludge sanitary landfill, which has a certain effect on whether to promote the use of the technology.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2014

Waste Stream Treatment and Waste Form Fabrication for Pyroprocessing of Used Nuclear Fuel

This report summarizes treatment and waste form options being evaluated for waste streams resulting from the electrochemical/pyrometallurgical (pyro ) processing of used oxide nuclear fuel. The technologies that are described are South Korean (Republic of Korea – ROK) and United States of America (US) ‘centric’ in the approach to treating pyroprocessing wastes and are based on the decade long collaborations between US and ROK researchers. Some of the general and advanced technologies described in this report will be demonstrated during the Integrated Recycle Test (IRT) to be conducted as a part of the Joint Fuel Cycle Study (JFCS) collaboration between US Department of Energy (DOE) and ROK national laboratories. The JFCS means to specifically address and evaluated the technological, economic, and safe guard issues associated with the treatment of used nuclear fuel by pyroprocessing. The IRT will involve the processing of commercial, used oxide fuel to recover uranium and transuranics. The recovered transuranics will then be fabricated into metallic fuel and irradiated to transmutate, or burn the transuranic elements to shorter lived radionuclides. In addition, the various process streams will be evaluated and tested for fission product removal, electrolytic salt recycle, minimization of actinide loss to waste streams and waste form fabrication and characterization. This report specifically addresses the production and testing of those waste forms to demonstrate their compatibility with treatment options and suitability for disposal.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2010

PAPER STUDY EVALUATIONS OF THE INTRODUCTION OF SMALL COLUMN ION EXCHANGE WASTE STREAMS TO THE DEFENSE WASTE PROCESSING FACILITY

The objective of this paper study is to provide guidance on the impact of Monosodium Titanate (MST) and Crystalline Silicotitanate (CST) streams from the Small Column Ion Exchange (SCIX) process on the Defense Waste Processing Facility (DWPF) flowsheet and glass waste form. A series of waste processing scenarios was evaluated, including projected compositions of Sludge Batches 8 through 17 (SB8 through SB17), MST additions, CST additions to Tank 40 or to a sludge batch preparation tank (Tank 42 or Tank 51, referred to generically as Tank 51 in this report), streams from the Salt Waste Processing Facility (SWPF), and two canister production rates. A wide array of potential glass frit compositions was used to support this assessment. The sludge and frit combinations were evaluated using the predictive models in the current DWPF Product Composition Control System (PCCS). The results were evaluated based on the number of frit compositions available for a particular sludge composition scenario. A large number of candidate frit compositions (e.g., several dozen to several hundred) is typically a good indicator of a sludge composition for which there is flexibility in forming an acceptable waste glass and meeting canister production rate commitments. The MST and CST streams will significantly increase the concentrations of certain components in glass, such as Nb{sub 2}O{sub 5}, TiO{sub 2}, and ZrO{sub 2}, to levels much higher than have been previously processed at DWPF. Therefore, several important assumptions, described in detail in the report, had to be made in performing the evaluations. The results of the paper studies, which must be applied carefully given the assumptions made concerning the impact of higher Ti, Zr, and Nb concentrations on model validity, provided several observations: (1) There was difficulty in identifying a reasonable number of candidate frits (and in some cases an inability to identify any candidate frits) when a waste loading of 40% is targeted for Sludge Batches 8, 16, and 17, regardless of the addition of SCIX or SWPF streams. This indicates that the blending strategy for these sludge batches should be reevaluated by Savannah River Remediation (SRR). (2) In general, candidate frits were available to accommodate CST additions to either Tank 40 or Tank 51. A larger number of candidate frits were typically available for the sludge batches when CST is added to Tank 51 rather than Tank 40, meaning that more compositional flexibility would be available for frit selection and DWPF operation. Note however that for SB8 and SB17, no candidate frits were available to accommodate CST going to Tank 40 with and without SWPF streams. The addition of SWPF streams generally improves the number of candidate frits available for processing of a given sludge batch. (3) The change in production rate from 40 Sludge Receipt and Adjustment Tank (SRAT) batches per year (i.e., the current production rate) to 75 SRAT batches per year, without SWPF streams included, had varied results in terms of the number of candidate frits available for processing of a given sludge batch. Therefore, this variable is not of much concern in terms of incorporating the SCIX streams. Note that the evaluation at 75 SRAT batches per year (approximately equivalent to 325 canisters per year) is more conservative in terms of the impact of SCIX streams as compared to a production rate of 400 canisters per year. Overall, the outcome of this paper study shows no major issues with the ability to identify an acceptable glass processing window when CST from the SCIX process is transferred to either Tank 40 or Tank 51. The assumptions used and the model limitations identified in this report must be addressed through further experimental studies, which are currently being performed. As changes occur to the planned additions of MST and CST, or to the sludge batch preparation strategy, additional evaluations will be performed to determine the potential impacts. As stated above, the issues with Sludge Batches 8, 16, and 17 should be further evaluated by SRR. A review of Chemical Process Cell (CPC) processing identified no changes to the recommendations from the previous review of the SCIX process impacts. Recommendations for testing were made during the previous review to evaluate the impact of CST on the rheological properties of DWPF process streams and evaluate the impact of CST on catalytic hydrogen generation during CPC processing.

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DOE OSTI2015

RCRA Part B Permit Application Nevada National Security Site (NNSS) for Waste Management Activities at the NNSS Mixed Waste Storage Unit (MWSU)

This volume of the Resource Conservation and Recovery Act (RCRA) permit application to the Nevada Division of Environmental Protection focuses on continued operation of the Mixed Waste Storage Unit at the Nevada National Security Site (NNSS), under the auspices of DOE’s National Nuclear Security Administration Nevada Field Office (NNSA/NFO). Low-level mixed waste (LLMW) accepted at the NNSS contains both radioactive and hazardous material components as defined by various laws and regulations. The Mixed Waste Storage Unit (MWSU) is located at the Area 5 Radioactive Waste Management Complex (RWMC). Existing facilities at the RWMC are used to store LLMW generated at or shipped to the NNSS prior to disposal at the Mixed Waste Disposal Unit (MWDU). The document describes the MWSU, its general design, its operation, the materials it stores, and relevant health and safety regulations with which NNSS complies. The currently permitted MWSU has been operated since December 2010. Each of the four designated storage areas is RCRA-compliant for the storage of hazardous waste. This application represents a renewal request by DOE for the permitted MWSU. For security reasons, some of the contents of the full application are not available for public viewing. This version of the application contains most but not all of the contents as submitted to the regulatory agencies.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2013

Progress of the High Level Waste Program at the Defense Waste Processing Facility - 13178

The Defense Waste Processing Facility at the Savannah River Site treats and immobilizes High Level Waste into a durable borosilicate glass for safe, permanent storage. The High Level Waste program significantly reduces environmental risks associated with the storage of radioactive waste from legacy efforts to separate fissionable nuclear material from irradiated targets and fuels. In an effort to support the disposition of radioactive waste and accelerate tank closure at the Savannah River Site, the Defense Waste Processing Facility recently implemented facility and flowsheet modifications to improve production by 25%. These improvements, while low in cost, translated to record facility production in fiscal years 2011 and 2012. In addition, significant progress has been accomplished on longer term projects aimed at simplifying and expanding the flexibility of the existing flowsheet in order to accommodate future processing needs and goals. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2017

The Effect of Ettringite on Cementitious Waste Form Development for Low- Activity Waste - 17170

The current Cast Stone formulation, with 8% ordinary Portland cement (OPC), 45% fly ash (FA), and 47% blast furnace slag (BFS), proposed for cementitious waste forms (CWFs) at the Hanford site has been shown to be inadequate for secondary liquid wastes sent to the Effluent Treatment Facility (ETF). This is due to the high sulfate concentrations and non-alkaline conditions present in the ETF waste stream that lead to the late formation of ettringite, [Ca{sub 6}Al{sub 2}(SO{sub 4}){sub 3}(OH){sub 12}.26(H{sub 2}O)], which can consequently cause undesirable swelling and cracks in the CWF that facilitate {sup 99}Tc release. To overcome this challenge, hydrated lime (HL), Ca(OH){sub 2}, can be used instead of FA to provide the Ca necessary to sequester sulfate early in the cast stone curing process through early formation of ettringite. Early ettringite formation minimizes the risk of localized disruptive action or harmful stress that lead to undesirable swelling and cracking of the CWF. Furthermore, early formation reduces the permeability of the CWF, further reducing the risk of {sup 99}Tc release and increasing structural stability. Two liquid waste simulants, 1) WTP off-gas condensate (WTP) and 2) Effluent Management Facility (EMF) process condensate combined with low activity waste (LAW) caustic scrubber (labeled EMF/CS), were prepared and tested for ettringite formation effects on HL-containing CWF development and {sup 99}Tc leachability. After curing for 28 days, X-ray diffraction analysis revealed that ettringite was formed in the early stages of curing for the CWFs prepared using both simulants. However, because of the higher sulfate concentration in the EMF/CS simulant and limited Ca and Al sources, some sulfate did not form ettringite during the early stages of curing, resulting in significant monolith swelling and cracking during subsequent leaching tests. Despite observable cracking in monoliths prepared with the EMF/CS simulant, low {sup 99}Tc release from HL-based waste forms was measured in later leaching periods tested by the EPA Method 1315 in both simulants. Ettringite-{sup 99}Tc co-precipitation batch experiments support a possible chemical sequestration mechanism that is hypothesized to contribute to the observed low {sup 99}Tc leach rates, which are likely the result of an additional chemical reaction that sequesters {sup 99}Tc rather than simply physical factors such as reduced porosity and permeability (or tortuosity). Overall these findings quantitatively support the use of HL to overcome the deleterious effects of sulfate-rich conditions on CWFs through early formation of ettringite and provide evidence for {sup 99}Tc release rates that fall within low risk levels reported by the United States Department of Energy (US DOE). (authors)

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DOE OSTI2021

Immobilization of cesium and iodine into Cs 3 Bi 2 I 9 perovskite-silica composites and core-shell waste forms with high waste loadings and chemical durability

Cs$_3$Bi$_2$I$_9$, a defect perovskite derivative, is a potential host phase to immobilize iodine and cesium with high waste loadings. In this work, two strategies were explored to form Cs$_3$Bi$_2$I$_9$-silica composites and a core-shell structure in order to improve chemical durability of waste form materials meanwhile maintaining high waste loadings. Cs$_3$Bi$_2$I$_9$ loadings as high as 70 wt.% were incorporated into a silica matrix to form silica-ceramic composites, and 20 wt.% Cs$_3$Bi$_2$I$_9$ was encapsulated into silica to form a core–shell structure by low temperature spark plasma sintering. Chemical durability of the composite and core-shell waste forms was evaluated by semi-dynamic leaching experiments, and Cs and I were incongruently released from waste form matrices. A BiOI alteration layer formed, acting as a passivation layer to reduce the release of radionuclides. The long-term iodine release rate was low (30 mg m$^{-2}$ day$^{-1}$) for the 70 wt.%Cs$_3$Bi$_2$I$_9$–silica composite leached in deionized water at 90 °C, which can be further reduced to 5 × 10$^{-3}$ mg m$^{-2}$ day$^{-1}$ for the 20 wt.% core-shell structure. This work highlights a robust way to immobilize the highly mobile radionuclides with high waste loadings through encapsulation into durable matrices and a surface passivating mechanism that can greatly reduce the elemental transport from waste form materials and significantly enhance their chemical durability.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

Unreviewed Disposal Question Evaluation: Disposal of the Los Alamos National Laboratory H3 Waste from the Weapons Engineering Tritium Facility at the Area 5 Radioactive Waste Management Site, Nevada National Security Site, Nye County, Nevada

This Unreviewed Disposal Question Evaluation (UDQE) assesses whether the Los Alamos National Laboratory (LANL) Tritium ( 3 H) Waste from the Weapons Engineering Tritium Facility (WETF) (LANL000000039, Revision 0 [LANL 2018]) is suitable for shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) on the Nevada National Security Site (NNSS). Disposal of the LANL 3H Waste from WETF waste stream meets all performance objectives of U.S. Department of Energy (DOE) Manual DOE M 435.1-1, “Radioactive Waste Management Manual,” Chapter IV, Section P (DOE 2011). The LANL 3 H Waste from the WETF waste stream is recommended for acceptance without conditions.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

Large Diameter Deep Borehole (LDDB) Disposal Design Option for Vitrified High-Level Waste (HLW) and Granular Wastes

This study considers the feasibility of large diameter deep boreholes for waste disposal. The conceptual approach considers examples of deep large diameter boreholes that have been successfully drilled, and also other deep borehole designs proposed in the literature. The objective for large diameter boreholes would be disposal of waste packages with diameters of 22 to 29 inches, which could enable disposal of waste forms such as existing vitrified high level waste. A large-diameter deep borehole design option would also be amenable to other waste forms including calcine waste, treated Na-bonded and Na-bearing waste, and Cs and Sr capsules.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2022

Life Cycle Analysis and Life Cycle Costing for Municipal Solid Waste (MSW) Management and Materials Redeployment to Support ARPA-E’s Potential Program on Waste to Energy and Materials

Municipal solid waste infrastructure in the United States contains complex supply chains to transport, sort, and sequester waste. This project developed models to estimate the environmental and economic costs of waste infrastructure in the U.S. using data from several municipalities. Life cycle costing (LCC) models were developed for waste management relevant supply chain steps, including waste collection, sorting, landfilling, waste-to-energy, ash processing, and recycling. A waste-to-materials and energy (WTM&E) life cycle analysis (LCA) and LCC dashboard was developed in collaboration with Argonne National Laboratory (ANL) and an LCC tool was developed for additional analysis.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
DOE OSTI2023

Improved Compaction Experiments and Modeling of Waste Isolation Pilot Plant Standard, Non-degraded, Waste Containers

A credible simulation of disposal room porosity at the Waste Isolation Pilot Plant (WIPP) requires a tenable compaction model for the 55-gallon waste containers within the room. A review of the legacy waste material model, however, revealed several out-of-date and untested assumptions that could affect the model’s compaction behavior. For example, the legacy model predicted non-physical tensile out-of-plane stresses under plane strain compression. (Plane strain compression is similar to waste compaction in the middle of a long drift.) Consequently, a suite of new compaction experiments were performed on containers filled with surrogate, non-degraded, waste. The new experiments involved uniaxial, triaxial, and hydrostatic compaction tests on quarter-scale and full-scale containers. Special effort was made to measure the volume strain during uniaxial and triaxial tests, so that the lateral strain could be inferred from the axial and volume strain. These experimental measurements were then used to calibrate a pressure dependent, viscoplastic, constitutive model for the homogenized compaction behavior of the waste containers. This new waste material model’s predictions agreed far better with the experimental measurements than the legacy model’s predictions, especially under triaxial and hydrostatic conditions. Under plane strain compression, the new model predicted reasonable compressive out-of-plane stresses, instead of tensile stresses. Moreover, the new model’s plane strain behavior was substantially weaker for the same strain, yet substantially stronger for the same porosity, than the legacy model’s behavior. Although room for improvement exists, the new model appears ready for prudent engineering use.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2013

Reevaluation Of Vitrified High-Level Waste Form Criteria For Potential Cost Savings At The Defense Waste Processing Facility

At the Savannah River Site (SRS) the Defense Waste Processing Facility (DWPF) has been immobilizing SRS's radioactive high level waste (HLW) sludge into a durable borosilicate glass since 1996. Currently the DWPF has poured over 3,500 canisters, all of which are compliant with the U. S. Department of Energy's (DOE) Waste Acceptance Product Specifications for Vitrified High-Level Waste Forms (WAPS) and therefore ready to be shipped to a federal geologic repository for permanent disposal. Due to DOE petitioning to withdraw the Yucca Mountain License Application (LA) from the Nuclear Regulatory Commission (NRC) in 2010 and thus no clear disposal path for SRS canistered waste forms, there are opportunities for cost savings with future canister production at DWPF and other DOE producer sites by reevaluating high-level waste form requirements and compliance strategies and reducing/eliminating those that will not negatively impact the quality of the canistered waste form.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2016

Evidence of Technetium and Iodine from a Sodalite-Bearing Ceramic Waste Form

Current plans for nuclear waste vitrification at the Hanford Tank Waste Treatment and Immobilization Plant (WTP) lack the capacity to treat all of the low activity waste (LAW) that is not encapsulated in the vitrified product. Several technologies are being considered to treat the excess LAW. One such technology is Fluidized Bed Steam Reforming (FBSR). The FBSR process results in a granular product composed of feldspathoid mineral phases that immobilize the major components in the LAW as well as other contaminants of concern (COCs), with Tc and I expected to be present in sodalite cages formed during the process. In order to meet compressive strength requirements at the Hanford Integrated Disposal Facility (IDF), the granular product may be encapsulated in a monolith. To demonstrate the ability of the technology to serve the mission of managing excess LAW, Single Pass Flow-Through (SPFT) tests have been performed on non-radioactive granular materials and granular materials encapsulated in a geopolymer binder produced at the engineering- and bench-scale as well as a granular product produced at the bench scale with actual Hanford tank waste. SPFT tests were conducted at 40 °C for durations up to 2 months with a flow-through solution buffered at pH 9. The forward reaction rate of the non-radioactive mineral product dissolution based on Si release for the granular product was measured to be (6.2 ± 2.1) × 10-4 g/m2d for the engineering-scale product and (13 ± 4.9) × 10-4 g/m2d for the bench-scale product. The resulting non-radioactive monoliths showed forward reaction rates based on Si release of (3.4 ± 1.1) × 10-4 g/m2d for the engineering-scale material and (4.2 ± 1.5) × 10-4 g/m2d for the bench-scale material demonstrating that encapsulation of the FBSR granular product in a monolith does not significantly alter the performance of the material. Finally, an FBSR granular product created at the bench scale using actual Hanford LAW gave similar release values and also demonstrated that Re and Tc show similar release behavior with a dilute-condition release rate of (1.1 ± 0.5) × 10-4 g/m2d for Tc and (1.6 ± 0.6) × 10-4 g/m2d for Re. We believe that this is the first demonstration to show that Re and I have similar release behavior and that similar behavior of Re and Tc also occurs. These results indicate that the FBSR mineral product may be a suitable supplementary immobilization technique at the Hanford site and they also suggest that both Tc and Re occupy similar sites in the sodalite cage structure.

fluidized bed steam reforming↗
DOE OSTI2014

Toward Understanding the Effect of Low-Activity Waste Glass Composition on Sulfur Solubility

The concentration of sulfur in nuclear waste glass melter feed must be maintained below the point where salt accumulates on the melt surface. The allowable concentrations may range from 0.37 to over 2.05 weight percent (of SO3 on a calcined oxide basis). If the amount of sulfur exceeds its tolerance level a molten salt will accumulate and upset melter operations and potentially shorten melter useful life. Therefore relatively conservative limits have been placed on sulfur loading in melter feed which in-turn significantly impacts the amount of glass that will be produced, in particular at the Hanford site. Crucible-scale sulfur solubility data and scaled melter sulfur tolerance data have been collected on simulated Hanford waste glasses over the last 15 years. These data were compiled and analyzed. A model was developed to predict the solubility of SO3 in glass based on 312 individual glass compositions. This model was shown to well represent the data, accounting for over 80% of the variation in data and was well validated. The model was also found to accurately predict the tolerance for sulfur in melter feed based on 19 scaled melter tests. The model is appropriate for control of waste glass processing which includes uncertainty quantification. The model also gives quantitative estimates of component concentration effects on sulfur solubility. The components that most increase sulfur solubility are Li2O > V2O5 ≈ TiO2 < CaO < P2O5 ≈ ZnO. The components that most decrease sulfur solubility are Cl > Cr2O3 > SiO2 ≈ ZrO2 > Al2O3.

Borosilicate↗
DOE OSTI2011

Nuclear Energy Advanced Modeling and Simulation Waste Integrated Performance and Safety Codes (NEAMS Waste IPSC): Subcontinuum-scale Verification and Validation Strategy

The objective of the U.S. Department of Energy Office of Nuclear Energy Advanced Modeling and Simulation Waste Integrated Performance and Safety Codes (NEAMS Waste IPSC) is to provide an integrated suite of computational modeling and simulation (M&S) capabilities to quantitatively assess the long-term performance of waste forms in the engineered and geologic environments of a radioactive-waste storage facility or disposal repository. Achieving the objective of modeling the performance of a disposal scenario requires describing processes involved in waste form degradation and radionuclide release at the subcontinuum scale, beginning with mechanistic descriptions of chemical reactions and chemical kinetics at the atomic scale, and upscaling into effective, validated constitutive models for input to high-fidelity continuum scale codes for coupled multiphysics simulations of release and transport. Verification and validation (V&V) is required throughout the system to establish evidence-based metrics for the level of confidence in M&S codes and capabilities, including at the subcontiunuum scale and the constitutive models they inform or generate. This Report outlines the nature of the V&V challenge at the subcontinuum scale, an approach to incorporate V&V concepts into subcontinuum scale modeling and simulation (M&S), and a plan to incrementally incorporate effective V&V into subcontinuum scale M&S destined for use in the NEAMS Waste IPSC work flow to meet requirements of quantitative confidence in the constitutive models informed by subcontinuum scale phenomena.

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