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At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

A Tool for Planning Near-Term Waste Transfers at the Hanford Site - 18491

Washington River Protection Solutions, LLC is developing a software tool designed to simulate near-term waste affecting activities at the Hanford Site. The tool will allow for timely planning and evaluation of near-term operational activities, as well as facilitate feedback incorporation from the field to enable rapid iteration of various planning scenarios for a Multi-Year Operating Plan. Implementation of this tool in the Multi-Year Operating Plan planning process will support building a better connection between execution of daily activities and long-term mission objectives. (authors)

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DOE OSTI2012

The Erosion And Corrosion Analysis Of Waste Transfer Primary Pipeline Sections From 241-SY Tank Farm (Final Report)

Three sections of primary transfer pipeline removed from the 241-SY Tank Farm in Hanford's 200 West area, labeled as SN-285, SN-286, and SN-278, were analyzed for the presence and amount of corrosion and erosion on the inside surface of the transfer pipe. All three sections of pipe, ranging in length between 6 and 8 in., were received at the 222-S Laboratory still in the pipe-in-pipe assembly.

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DOE OSTI2020

Transfer and Flushing Evaluation for Potential Precipitated Solids in the 241-AP-106 to EMF Transfer Pipeline for DFLAW

Waste transfer pipeline flushing is necessary to maintain pipeline performance, but added flush fluid increases the nuclear waste inventory. During the Direct Feed Low-Activity Waste (DFLAW) mission, waste transfer lines from the Interim Low-Activity Waste Storage Tank (i.e., 241-AP-106) to the Hanford Waste Treatment and Immobilization Plant (WTP) Low-Activity Waste (LAW) Facility must have the capability of being flushed to prevent accumulation of solids and to mitigate corrosion concerns. Operational experience at Hanford has shown that the solids precipitation occurs during processing operations from dilute Hanford liquids. Pacific Northwest National Laboratory was requested to evaluate the potential precipitated solid particle transport and flushing operational capabilities of the AP-106 through the Effluent Management Facility (EMF) low-point drain LAW feed pipeline. The evaluation results do not provide operational requirements, but rather provide a scoping basis for understanding the potential operational significance of solids precipitation in the pipeline. The salt and aluminum phase solids most likely to precipitate from the LAW feeds during cooling, evaporation, or mixing have particle densities that are estimated to range from 1.62 to 2.78 g/mL and a spherical particle size range of 8 to 2100 μm, depending on the solid phase considered. Application of the method to calculate the critical deposition velocity required by TFC-ENG-STD-26 at conservatively bounding estimates for the solids concentrations demonstrates that potentially precipitated solids may deposit on the bottom of the transfer pipe invert at the lower LAW feed pipeline flow rate, but the upper LAW feed pipeline flow rate will likely prevent deposition. The system pressure limit for the AP-106 through the EMF low-point drain LAW feed pipeline likely exceeds any pressure loss at a calculated critical deposition velocity even for the most adverse potential precipitated solid. However, should solids settle as a result of no-flow conditions, the flow capabilities of the AP-106 through the EMF low-point drain LAW feed pipeline are shown, based on the available literature, to be potentially inadequate for effective flushing operations to remove solids, even at solids concentrations below the maximum specified for LAW feed. Thus, stepwise solids accumulations over multiple transfers may be an issue, and eventual line plugging may occur. Further inadequacies may potentially be realized should the cohesive nature of certain precipitates be accounted for.

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DOE OSTI2013

Simulant Development for Hanford Tank Farms Double Valve Isolation (DVI) Valves Testing

Leakage testing of a representative sample of the safety-significant isolation valves for Double Valve Isolation (DVI) in an environment that simulates the abrasive characteristics of the Hanford Tank Farms Waste Transfer System during waste feed delivery to the Waste Treatment and Immobilization Plant (WTP) is to be conducted. The testing will consist of periodic leak performed on the DVI valves after prescribed numbers of valve cycles (open and close) in a simulated environment representative of the abrasive properties of the waste and the Waste Transfer System. The valve operations include exposure to cycling conditions that include gravity drain and flush operation following slurry transfer. The simulant test will establish the performance characteristics and verify compliance with the Documented Safety Analysis. Proper simulant development is essential to ensure that the critical process streams characteristics are represented, National Research Council report “Advice on the Department of Energy's Cleanup Technology Roadmap: Gaps and Bridges”

DVI Simulant↗
DOE OSTI2020

Development of Acoustic Backscatter for In Situ Monitoring of Nuclear Sludge Wastes During Transfer - 20117

This paper presents an overview into the use of acoustic backscatter systems (ABS) for the in situ characterization of nuclear waste sludge concentration, size and aggregation, highlighting key achievements from the University of Leeds. Previous projects funded through the Engineering and Physical Sciences Research Council (EPSRC) UK and Innovate UK are firstly reviewed and linked to current research within the new TRANSCEND consortium. Detailed are a number of developments at various stages of technology readiness level, from the use of ABS to monitor small-scale sludge settling in columns, to large-scale jet-mixing and waste transfer operations. Current work with Sellafield Ltd will see new technology and world leading analysis methods deployed to measure the consolidation of complex wastes currently undergoing containment, the first time full industrial utilization of these systems has been achieved. (authors)

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DOE OSTI2020

Erosion-Corrosion Detection in Carbon Steel Pipe Loops using SRNLs Thickness and Mass Loss Measurement Coupons - 20464

Structural health of waste transfer infrastructure is of utmost importance to DOE and communities surrounding their active sites. A Fitness-for-Service (FFS) program for the Waste Transfer System has been implemented by the US Department of Energy (DOE) for the purposes of evaluating and quantifying the degradation of critical components. Currently, the method of approach is to section and evaluate pipelines that have been removed at end service. In order to augment data collection methods applied to making lifespan estimates of waste transfer system components, Florida International University (FIU) has been investigating new-technology based strategies for quantifying the rate of degradation. Present research considers the option of a coupon system installed on a section of pipe at points of interest that will provide easy access to high resolution measurements of erosion/corrosion rates during operation. Researchers at Savannah River National Laboratory (SRNL) have developed this novel solution for in situ erosion and corrosion measurements in many applicable locations such as tanks, pipes, ducts, and injection points. The coupons are approximately 12.7 mm (1/2 inch) in diameter and 25.4 mm (1 inch) in length and can be placed in the pipe sections using Swagelok compression fittings. The coupon design allows for monitoring of the total degradation resulting from corrosion and erosion. High-resolution Ultrasonic Thickness (UT) testing allows in-situ monitoring of both degradation mechanisms. When removed from the system mass loss resulting from corrosion and erosion may also be evaluated. Experimental testing at FIU implemented the SRNL coupon system in a 6.10 meter (20 foot) pipe loop system comprised of 50.8 mm (2 inch) and 76.2 mm (3 inch) pipe sections in order to replicate expected use cases at the sites. Operational conditions were emulated by pumping abrasive materials through the pipeline at full capacity and collecting measurements from the SRNL coupons. Initial testing was conducted by circulating water followed by a mixture of sand and water for uniform wear rates. Thickness changes and mass loss were measured, and the surface exposed to the process fluid was observed for visual evidence of characteristic wear patterns resulting from an erosive environment. The test matrix consisted of several hours of operation and using fine, medium and coarse grain sands. Test results were analyzed to check for all three parameters (mass loss/gain, thickness change and surface patters) which could provide estimates of the remaining useful life of the pipe sections. Thus, the research presents the findings of this evaluation of the SRNL coupons as a means for conducting high accuracy, cost effective in-situ analysis of pipeline and waste transfer systems for erosion and corrosion susceptibility. (authors)

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DOE OSTI2019

Career Development through Discreet Simulation Modeling - 19009

The cleanup mission of the Department of Energy (DOE) Office of River Protection (ORP) at the Hanford Site is to immobilize 212,000 m3 (56 million gallons) of nuclear waste, currently stored in 177 underground tanks, at the Waste Treatment and Immobilization Plant (WTP) and associated supplemental treatment facilities. Waste transfers to and from the WTP utilize the intricate Hanford Waste Feed Delivery (WFD) system, a network composed of: double-shell tanks (DSTs), single shell tanks (SSTs), the effluent treatment facility (ETF), a large number of pumps, valves, and leak detectors, and thousands of feet of underground transfer lines. This equipment must be prepared to safely and reliably transfer waste to the WTP. This study used discrete event simulation modeling to explore the behavior of the waste transfer system to identify areas of improvement. Two models and their subsequent results are presented: the Effluent Treatment Facility and the next-to-be-retrieved single-shell tanks (A/AX Farms). This study focused on identifying throughput bottlenecks, operational constraints, choke-point analysis, and redundancy in equipment, process design, and operational strategy. Analysis performed on the ETF OR Model indicated that the existing facility operation strategy will not result in a sufficient throughput to prevent WTP melter idling. Furthermore, in the absence of equipment failures, the facility was still shown to be unable to reach the required throughput to prevent melter idling. It is concluded that ETF system maintenance events are currently the main bottlenecks in the ETF facility. Analysis performed on the SST (A/AX) OR model indicate that the main drivers of the retrieval schedule are the hard retrieval start dates for each SST tank. In addition, it was concluded that operating the ventilation trains in parallel results in 15 times less retrieval interruptions and shortens the retrieval durations. (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 OSTI2012

Waste disposal technology transfer matching requirement clusters for waste disposal facilities in China

Highlights: Black-Right-Pointing-Pointer We outline the differences of Chinese MSW characteristics from Western MSW. Black-Right-Pointing-Pointer We model the requirements of four clusters of plant owner/operators in China. Black-Right-Pointing-Pointer We examine the best technology fit for these requirements via a matrix. Black-Right-Pointing-Pointer Variance in waste input affects result more than training and costs. Black-Right-Pointing-Pointer For China technology adaptation and localisation could become push, not pull factors. - Abstract: Even though technology transfer has been part of development aid programmes for many decades, it has more often than not failed to come to fruition. One reason is the absence of simple guidelines or decision making tools that help operators or plant owners to decide on the most suitable technology to adopt. Practical suggestions for choosing the most suitable technology to combat a specific problem are hard to get and technology drawbacks are not sufficiently highlighted. Western counterparts in technology transfer or development projects often underestimate or don't sufficiently account for the high investment costs for the imported incineration plant; the differing nature of Chinese MSW; the need for trained manpower; and the need to treat flue gas, bunker leakage water, and ash, all of which contain highly toxic elements. This article sets out requirements for municipal solid waste disposal plant owner/operators in China as well as giving an attribute assessment for the prevalent waste disposal plant types in order to assist individual decision makers in their evaluation process for what plant type might be most suitable in a given situation. There is no 'best' plant for all needs and purposes, and requirement constellations rely on generalisations meaning they cannot be blindly applied, but an alignment of a type of plant to a type of owner or operator can realistically be achieved. To this end, a four-step approach is suggested and a technology matrix is set out to ease the choice of technology to transfer and avoid past errors. The four steps are (1) Identification of plant owner/operator requirement clusters; (2) Determination of different municipal solid waste (MSW) treatment plant attributes; (3) Development of a matrix matching requirement clusters to plant attributes; (4) Application of Quality Function Deployment Method to aid in technology localisation. The technology transfer matrices thus derived show significant performance differences between the various technologies available. It is hoped that the resulting research can build a bridge between technology transfer research and waste disposal research in order to enhance the exchange of more sustainable solutions in future.

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DOE OSTI2017

Comparison of Exhibited Wear in Tefzel?, Kynar?, and UHMWPE Valve Seats Exposed to Cyclic Operations with Abrasive Slurry - 17519

Pacific Northwest National Laboratory (PNNL) conducted abrasive-wear testing of ball valves used for double valve isolation in nuclear waste process lines. The valve seat materials consisted of Kynar{sup R}, Tefzel{sup R}, and ultra-high-molecular-weight polyethylene (UHMWPE). Cycle testing was conducted for 1500 operating cycles for the Kynar{sup R} and Tefzel{sup R} valve seats and 5500 cycles for the UHMWPE valve seats. A valve operational cycle consisted of slurry flow, slurry gravity drain, flush water flow, and flush water gravity drain. Both two-way and three-way valves were evaluated, and valves were configured in simulated manifolds so the impact of serving various operational functions (e.g., slurry, flush, or drain control) could be evaluated as some valves are flushed prior to being cycled and others are not. Testing was conducted in PNNL's Multi-Phase Transport Evaluation Loop Facility using a performance-based simulant developed by PNNL specifically for this test program to emulate abrasive slurries for Hanford Tank Farms Waste Transfer System during single-shell tank retrieval and waste feed delivery to the Hanford Tank Waste Treatment and Immobilization Plant. Pre- and post-test valve tear-down evaluations were conducted to observe changes in the condition of internal components for the various seat materials. The various forms of physical wear observed for the different seat materials are presented. The wear results can be used to assess seat materials and valve configurations for application to waste transfer operations, and the observed wear mechanisms can provide insight into assessing valve service life. This information will be used to identify and select additional valve designs that should be evaluated for certification for future use. (authors)

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DOE OSTI2022

Measurement of Total, Elemental, and Methyl Mercury in Hanford Tank Waste: Technology Transfer from PNNL to Hanford 222-S Laboratory

This report describes the chemical separations used to measure the amount and chemical form of mercury in Hanford tank waste and provides the technical basis and recommendations for transferring and implementing this new ultra-trace mercury analytical technique at Hanford’s 222-S Laboratory. In the Hanford tank waste, mercury can exist as either elemental, inorganic, or organic mercury species. Of key interest is understanding the quantification and speciation of total (elemental + inorganic + organic), elemental, and organic (assumed to be only methyl mercury) mercury. The tanks may also have other organic mercury species, but their direct measurement is outside the scope of this report.

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DOE OSTI2012

Strong-Sludge Gas Retention and Release Mechanisms in Clay Simulants

The Hanford Site has 28 double-shell tanks (DSTs) and 149 single-shell tanks (SSTs) containing radioactive wastes that are complex mixes of radioactive and chemical products. The mission of the Department of Energy's River Protection Project is to retrieve and treat the Hanford tank waste for disposal and close the tank farms. A key aspect of the mission is to retrieve and transfer waste from the SSTs, which are at greater risk for leaking, into DSTs for interim storage until the waste is transferred to and treated in the Waste Treatment and Immobilization Plant. There is, however, limited space in the existing DSTs to accept waste transfers from the SSTs, and approaches to overcoming the limited DST space will benefit the overall mission. The purpose of this study is to summarize and analyze the key previous experiment that forms the basis for the relaxed controls and to summarize progress and results on new experiments focused on understanding the conditions that result in low gas retention. The previous large-scale test used about 50 m3 of sediment, which would be unwieldy for doing multiple parametric experiments. Accordingly, experiments began with smaller-scale tests to determine whether the desired mechanisms can be studied without the difficulty of conducting very large experiments. The most significant results from the current experiments are that progressively lower gas retention occurs in tests with progressively deeper sediment layers and that the method of gas generation also affects the maximum retention. Based on the results of this study, it is plausible that relatively low gas retention could occur in sufficiently deep tank waste in DSTs. The current studies and previous work, however, have not explored how gas retention and release will behave when two or more layers with different properties are present.

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DOE OSTI2013

Review Of Rheology Models For Hanford Waste Blending

The area of rheological property prediction was identified as a technology need in the Hanford Tank Waste – waste feed acceptance initiative area during a series of technical meetings among the national laboratories, Department of Energy-Office of River Protection, and Hanford site contractors. Meacham et al. delivered a technical report in June 2012, RPP-RPT-51652 “One System Evaluation of Waste Transferred to the Waste Treatment Plant” that included estimating of single shell tank waste Bingham plastic rheological model constants along with a discussion of the issues inherent in predicting the rheological properties of blended wastes. This report was selected as the basis for moving forward during the technical meetings. The report does not provide an equation for predicting rheological properties of blended waste slurries. The attached technical report gives an independent review of the provided Hanford rheological data, Hanford rheological models for single tank wastes, and Hanford rheology after blending provided in the Meacham report. The attached report also compares Hanford to SRS waste rheology and discusses some SRS rheological model equations for single tank wastes, as well as discussing SRS experience with the blending of waste sludges with aqueous material, other waste sludges, and frit slurries.

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DOE OSTI2021

Measurement of Iodine, Iodide, and Iodate in Hanford Tank Waste: Technology Transfer from PNNL to Hanford 222-S Laboratory

This report summarizes the measurement of the inorganic chemical forms of iodine in Hanford tank waste. The Hanford tank wastes have roughly a part per million iodine. Part of the iodine is the long-lived beta emitter 129I, and the rest is stable 127I. Because tank waste iodine is radioactive and radiotoxic, its chemical form must be known so that its behavior in the vitrification process can be reliably known and anticipated in various waste streams (glass, secondary liquid and solid waste, and offgas emissions) at Hanford. Iodine in tank wastes exists in the inorganic chemical forms iodide and iodate (and possibly also periodate) and also as organic forms such as alkyl iodides. The measurement of organic iodides is very different from the measurement of inorganic forms and is outside the scope of this report. The inorganic chemical forms are chemically separated, in sequence, from the raw tank waste using solvent extractions and several redox reactions, then measured by ICP-MS. The inorganic chemical forms of iodine are chemically reactive, and so is the tank waste. The chemistry must be carefully designed to avoid unintended reactions that could convert one form of iodine to another during the analysis, which would skew the data and report iodine in the wrong chemical form. This iodine analysis, developed at PNNL, is being transferred to the DOE 222-S Laboratory on the Hanford Site, in Washington State, for implementation during waste processing operations.

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DOE OSTI2014

Polybrominated diphenyl ethers in e-waste: Level and transfer in a typical e-waste recycling site in Shanghai, Eastern China

Highlights: • PBDEs were detected in the majority of e-waste. • PBDEs were found in TVs made in China after 1990. • The levels of ΣPBDEs in e-waste made in Japan far exceed the threshold limit of RoHS. • The inappropriate recycling and disposal of e-waste is an important source of PBDEs. - Abstract: Very few data for polybrominated diphenyl ethers (PBDEs) were available in the electronic waste (e-waste) as one of the most PBDEs emission source. This study reported concentrations of PBDEs in e-waste including printer, rice cooker, computer monitor, TV, electric iron and water dispenser, as well as dust from e-waste, e-waste dismantling workshop and surface soil from inside and outside of an e-waste recycling plant in Shanghai, Eastern China. The results showed that PBDEs were detected in the majority of e-waste, and the concentrations of ΣPBDEs ranged from not detected to 175 g/kg, with a mean value of 10.8 g/kg. PBDEs were found in TVs made in China after 1990. The mean concentrations of ΣPBDEs in e-waste made in Korea, Japan, Singapore and China were 1.84 g/kg, 20.5 g/kg, 0.91 g/kg, 4.48 g/kg, respectively. The levels of ΣPBDEs in e-waste made in Japan far exceed the threshold limit of RoHS (1.00 g/kg). BDE-209 dominated in e-waste, accounting for over 93%. The compositional patterns of PBDEs congeners resembled the profile of Saytex 102E, indicating the source of deca-BDE. Among the samples of dust and surface soil from a typical e-waste recycling site, the highest concentrations of Σ{sub 18}PBDEs and BDE-209 were found in dust in e-waste, ranging from 1960 to 340,710 ng/g and from 910 to 320,400 ng/g, which were 1–2 orders of magnitude higher than other samples. It suggested that PBDEs released from e-waste via dust, and then transferred to surrounding environment.

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DOE OSTI2019

Development of a Preliminary Performance Assessment to Support Single-Shell Tank Waste Retrieval - 19446

A preliminary Performance Assessment (PA) of Single-Shell Tank (SST) Waste Management Area A-AX (WMA A-AX) located at DoE's Hanford Site in southeastern Washington is being conducted to satisfy the requirements of the Hanford Federal Facility Agreement and Consent Order (HFFACO), as well as other Federal and State requirements of closure plans and permits. The WMA A-AX PA effort is assessing the fate, transport, and impacts of radionuclides and hazardous chemicals within residual wastes left in tanks, ancillary equipment, and facilities in their assumed closed configuration, and the subsequent risks to humans into the far future. WMA A-AX includes the 241-A Tank Farm (A Farm), the 241-AX Tank Farm (AX Farm), and the ancillary equipment associated with each Farm. There are six underground SSTs in A Farm, and four underground SSTs in AX Farm. Each of these SSTs have a storage capacity of 1,000,000 gallons. A complex waste transfer system of ancillary equipment supported the transfer and storage of waste within WMA A-AX SSTs. This ancillary equipment includes transfer lines, catch tanks, diversion boxes, vaults, valve pits, and other miscellaneous structures. This paper emphasizes the development of the PA effort focused on radiological impacts to meet the requirements for a closure authorization under DOE Order 435.1. Lessons learned from retrieval and development of a recently completed PA of the nearby Waste Management Area C (WMA C) led to the decision to develop a preliminary PA for WMA A-AX prior to initiation of retrieval efforts so that a site-specific risk management capability could be available to support anticipated retrieval decisions. The technical approach for the PA analysis includes developing both a process-level model using site-specific hydrogeological data, as well as a system-level model. The system model is being developed to facilitate uncertainty and sensitivity analyses being conducted in the PA effort. Preliminary results of the DOE Order 435.1 PA are evaluating potential impacts to the groundwater and air pathways to determine radiation exposure once radionuclides are released to the environment from residual waste after closure of the tank farm. To meet other analysis requirements in DOE Order 435.1, the PA effort must also evaluate potential radiological impacts from inadvertent intruder scenarios into the closed WMA A-AX facility. The results of the PA evaluation will be compared to performance objectives and measures in the DOE Order 435.1 to support retrieval and eventual closure decisions at WMA A-AX. (authors)

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DOE OSTI2016

Overcoming Waste Removal Challenges at Savannah River Site: A Case Study of Tank 15 - 16198

Tank 15 is a High Level Waste Tank at the Savannah River Site containing sludge waste that had been allowed to dry due to several flaws in the primary tank wall. In order to remove the tank waste, the sludge had to first be re-hydrated. Due to the age of Tank 15 and the thirty years of 'dry sludge tank' status, there were numerous technical challenges and risks that had to be addressed to demonstrate operational readiness to add liquid to a tank with known flaws. Liquid management was a key to readiness since Tank 15 did not have the infrastructure to mitigate waste accumulating in the annulus or to transfer waste out of the primary tank as a means to control a large leak. The project team's fundamental expectation was that some amount of liquid would migrate to the annulus through identified flaws as the sludge waste was re-hydrated. Communication was crucial to ensuring this expectation was propagated to management, the customer, and the regulators. Equipment upgrades, provisions for annulus liquid management (monitoring and removal), and readiness for outgoing transfers mitigated waste migration. Liquid addition methodology and facility modifications were developed to safely re-hydrate the sludge while monitoring the integrity of the primary tank. These efforts culminated in successfully adding 697 m{sup 3} (184,000 gal) of liquid to Tank 15, re-hydrating the sludge waste. (authors)

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