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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 1,009 records · Page 56
All sourcesNASA NTRSDOE OSTI
DOE OSTI2014

Development And Initial Testing Of Off-Gas Recycle Liquid From The WTP Low Activity Waste Vitrification Process - 14333

The Waste Treatment and Immobilization Plant (WTP) process flow was designed to pre-treat feed from the Hanford tank farms, separate it into a High Level Waste (HLW) and Low Activity Waste (LAW) fraction and vitrify each fraction in separate facilities. Vitrification of the waste generates an aqueous condensate stream from the off-gas processes. This stream originates from two off-gas treatment unit operations, the Submerged Bed Scrubber (SBS) and the Wet Electrospray Precipitator (WESP). Currently, the baseline plan for disposition of the stream from the LAW melter is to recycle it to the Pretreatment facility where it gets evaporated and processed into the LAW melter again. If the Pretreatment facility is not available, the baseline disposition pathway is not viable. Additionally, some components in the stream are volatile at melter temperatures, thereby accumulating to high concentrations in the scrubbed stream. It would be highly beneficial to divert this stream to an alternate disposition path to alleviate the close-coupled operation of the LAW vitrification and Pretreatment facilities, and to improve long-term throughput and efficiency of the WTP system. In order to determine an alternate disposition path for the LAW SBS/WESP Recycle stream, a range of options are being studied. A simulant of the LAW Off-Gas Condensate was developed, based on the projected composition of this stream, and comparison with pilot-scale testing. The primary radionuclide that vaporizes and accumulates in the stream is Tc-99, but small amounts of several other radionuclides are also projected to be present in this stream. The processes being investigated for managing this stream includes evaporation and radionuclide removal via precipitation and adsorption. During evaporation, it is of interest to investigate the formation of insoluble solids to avoid scaling and plugging of equipment. Key parameters for radionuclide removal include identifying effective precipitation or ion adsorption chemicals, solid-liquid separation methods, and achievable decontamination factors. Results of the radionuclide removal testing indicate that the radionuclides, including Tc-99, can be removed with inorganic sorbents and precipitating agents. Evaporation test results indicate that the simulant can be evaporated to fairly high concentration prior to formation of appreciable solids, but corrosion has not yet been examined.

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

Single Stage Contactor Testing Of The Next Generation Solvent Blend

The Modular Caustic Side Solvent Extraction (CSSX) Unit (MCU) facility at the Savannah River Site (SRS) is actively pursuing the transition from the current BOBCalixC6 based solvent to the Next Generation Solvent (NGS)-MCU solvent to increase the cesium decontamination factor. To support this integration of NGS into the MCU facility the Savannah River National Laboratory (SRNL) performed testing of a blend of the NGS (MaxCalix based solvent) with the current solvent (BOBCalixC6 based solvent) for the removal of cesium (Cs) from the liquid salt waste stream. This testing utilized a blend of BOBCalixC6 based solvent and the NGS with the new extractant, MaxCalix, as well as a new suppressor, tris(3,7dimethyloctyl) guanidine. Single stage tests were conducted using the full size V-05 and V-10 liquid-to-liquid centrifugal contactors installed at SRNL. These tests were designed to determine the mass transfer and hydraulic characteristics with the NGS solvent blended with the projected heel of the BOBCalixC6 based solvent that will exist in MCU at time of transition. The test program evaluated the amount of organic carryover and the droplet size of the organic carryover phases using several analytical methods. The results indicate that hydraulically, the NGS solvent performed hydraulically similar to the current solvent which was expected. For the organic carryover 93% of the solvent is predicted to be recovered from the stripping operation and 96% from the extraction operation. As for the mass transfer, the NGS solvent significantly improved the cesium DF by at least an order of magnitude when extrapolating the One-stage results to actual Seven-stage extraction operation with a stage efficiency of 95%.

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

Small Gas Bubble Experiment for Mitigation of Cavitation Damage and Pressure Waves in Short-pulse Mercury Spallation Targets

Populations of small helium gas bubbles were introduced into a flowing mercury experiment test loop to evaluate mitigation of beam-pulse induced cavitation damage and pressure waves. The test loop was developed and thoroughly tested at the Spallation Neutron Source (SNS) prior to irradiations at the Los Alamos Neutron Science Center - Weapons Neutron Research Center (LANSCE-WNR) facility. Twelve candidate bubblers were evaluated over a range of mercury flow and gas injection rates by use of a novel optical measurement technique that accurately assessed the generated bubble size distributions. Final selection for irradiation testing included two variations of a swirl bubbler provided by Japan Proton Accelerator Research Complex (J-PARC) collaborators and one orifice bubbler developed at SNS. Bubble populations of interest consisted of sizes up to 150 m in radius with achieved gas void fractions in the 10^-5 to 10^-4 range. The nominal WNR beam pulse used for the experiment created energy deposition in the mercury comparable to SNS pulses operating at 2.5 MW. Nineteen test conditions were completed each with 100 pulses, including variations on mercury flow, gas injection and protons per pulse. The principal measure of cavitation damage mitigation was surface damage assessment on test specimens that were manually replaced for each test condition. Damage assessment was done after radiation decay and decontamination by optical and laser profiling microscopy with damaged area fraction and maximum pit depth being the more valued results. Damage was reduced by flow alone; the best mitigation from bubble injection was between half and a quarter that of flow alone. Other data collected included surface motion tracking by three laser Doppler vibrometers (LDV), loop wall dynamic strain, beam diagnostics for charge and beam profile assessment, embedded hydrophones and pressure sensors, and sound measurement by a suite of conventional and contact microphones.

bubbles↗
DOE OSTI2013

Operating Experience and Lessons Learned in the Use of Soft-Sided Packaging for Transportation and Disposal of Low Activity Radioactive Waste

This paper describes the operating experience and lessons learned at U.S. Department of Energy (DOE) sites as a result of an evaluation of potential trailer contamination and soft-sided packaging integrity issues related to the disposal of low-level and mixed low-level (LLW/MLLW) radioactive waste shipments. Nearly 4.3 million cubic meters of LLW/MLLW will have been generated and disposed of during fiscal year (FY) 2010 to FY 2015—either at commercial disposal sites or disposal sites owned by DOE. The LLW/MLLW is packaged in several different types of regulatory compliant packaging and transported via highway or rail to disposal sites safely and efficiently in accordance with federal, state, and local regulations and DOE orders. In 1999, DOE supported the development of LLW containers that are more volumetrically efficient, more cost effective, and easier to use as compared to metal or wooden containers that existed at that time. The DOE Idaho National Engineering and Environmental Laboratory (INEEL), working in conjunction with the plastic industry, tested several types of soft-sided waste packaging systems that meet U.S. Department of Transportation requirements for transport of low specific activity and surface contaminated objects. Since then, soft-sided packaging of various capacities have been used successfully by the decontamination and decommissioning (D&D) projects to package, transport, and dispose D&D wastes throughout the DOE complex. The joint team of experts assembled by the Energy Facility Contractors Group from DOE waste generating sites, DOE and commercial waste disposal facilities, and soft-sided packaging suppliers conducted the review of soft-sided packaging operations and transportation of these packages to the disposal sites. As a result of this evaluation, the team developed several recommendations and best practices to prevent or minimize the recurrences of equipment contamination issues and proper use of soft-sided packaging for transport and disposal of waste.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2015

System and method for the identification of radiation in contaminated rooms

Devices and methods for the characterization of areas of radiation in contaminated rooms are provided. One such device is a collimator with a collimator shield for reducing noise when measuring radiation. A position determination system is provided that may be used for obtaining position and orientation information of the detector in the contaminated room. A radiation analysis method is included that is capable of determining the amount of radiation intensity present at known locations within the contaminated room. Also, a visual illustration system is provided that may project images onto the physical objects, which may be walls, of the contaminated room in order to identify the location of radioactive materials for decontamination.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2015

Special Analysis for the Disposal of the West Valley Demonstration Project Extraction Cell 2 Low Density Waste Stream at the Area 5 Radioactive Waste Management Site, Nevada National Security Site, Nye County, Nevada

This special analysis (SA) evaluates whether the West Valley Demonstration Project (WVDP) Extraction Cell 2 Low Density waste stream is suitable for disposal by shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) on the Nevada National Security Site (NNSS). The WVDP Low Density waste stream consists of debris contaminated during the decontamination and decommissioning (D&D) of Extraction Cell 2 at the WVDP (WVDP 2015). The WVDP Low Density waste stream required an SA because the radium-226 (226Ra) activity concentration exceeds the NNSS Waste Acceptance Criteria (WAC) Action Level (U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office [NNSA/NFO] 2013). The effect of adding the WVDP Low Density waste stream inventory to the inventory of waste disposed through the end of FY 2014 was evaluated with the A5 RWMS v 4.119 PA model. The results indicate that all performance objectives can be met with disposal of the WVDP Low Density in a SLB trench. Addition of the WVDP Low Density inventory slightly increases the 222Rn flux density, but the maximum mean and 95th percentile flux density remain less than the performance objective throughout the compliance period. The WVDP Low Density waste stream had no significant effect on the maximum mean and 95th percentile for all other PA results. The WVDP Low Density waste stream, therefore, is suitable for disposal by SLB at the Area 5 RWMS.

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

Current Developments in Prokaryotic Single Cell Whole Genome Amplification

Our approach to prokaryotic single-cell Whole Genome Amplification at the JGI continues to evolve. To increase both the quality and number of single-cell genomes produced, we explore all aspects of the process from cell sorting to sequencing. For example, we now utilize specialized reagents, acoustic liquid handling, and reduced reaction volumes eliminate non-target DNA contamination in WGA reactions. More specifically, we use a cleaner commercial WGA kit from Qiagen that employs a UV decontamination procedure initially developed at the JGI, and we use the Labcyte Echo for tip-less liquid transfer to set up 2uL reactions. Acoustic liquid handling also dramatically reduces reagent costs. In addition, we are exploring new cell lysis methods including treatment with Proteinase K, lysozyme, and other detergents, in order to complement standard alkaline lysis and allow for more efficient disruption of a wider range of cells. Incomplete lysis represents a major hurdle for WGA on some environmental samples, especially rhizosphere, peatland, and other soils. Finding effective lysis strategies that are also compatible with WGA is challenging, and we are currently assessing the impact of various strategies on genome recovery.

09 BIOMASS FUELS↗
DOE OSTI2016

Systems and methods for harvesting and storing materials produced in a nuclear reactor

Systems produce desired isotopes through irradiation in nuclear reactor instrumentation tubes and deposit the same in a robust facility for immediate shipping, handling, and/or consumption. Irradiation targets are inserted and removed through inaccessible areas without plant shutdown and placed in the harvesting facility, such as a plurality of sealable and shipping-safe casks and/or canisters. Systems may connect various structures in a sealed manner to avoid release of dangerous or unwanted matter throughout the nuclear plant, and/or systems may also automatically decontaminate materials to be released. Useable casks or canisters can include plural barriers for containment that are temporarily and selectively removable with specially-configured paths inserted therein. Penetrations in the facilities may limit waste or pneumatic gas escape and allow the same to be removed from the systems without over-pressurization or leakage. Methods include processing irradiation targets through such systems and securely delivering them in such harvesting facilities.

07 ISOTOPE AND RADIATION SOURCES↗
DOE OSTI2016

Probabilistic Anthrax Risk Assessment Tool v. 1.0

PARAT is a human health risk assessment tool for quantifying the uncertainty associated with inhalational exposures to Bacillus anthracis (Ba), which is the causative agent for contracting anthrax. The tool has a unique set of aerosol transport algorithms to account for indoor-outdoor deposition, re-aerosolization, building infiltration/exfiltration, and ventilation system effects, all of which are coded to preserve mass. PARAT is currently implemented within a Microsoft Excel application along with the Crystal Ball third-party add-on software that provides a Monte Carlo simulation technique for quantifying uncertainty in model predictions. The tool predicts both air and surface concentrations, as well as the fraction of the population that would contract a lethal dose from exposure to Ba. The tool can be used by decision makers to support Preliminary Remediaiton Goals (PRGs) to guide sampling and decontamination decisions after a release of Ba. Currently the de facto standard for recovery from a Ba release is a sampling protocol whereby all of the surface samples sent to a laboratory have to meet the requirement of “no culturable growth” on the media. This could lead to some very costly cleanups, as was evidenced following the 2001 anthrax letter attack responses. So PARAT may provide decision makers and risk assessors the ability to negotiate risk-based endpoints for the recovery process.

Knowlton, Robert↗
DOE OSTI2015

Sampling Tools for Contaminated Hot Cells and Remotely Accessed Tanks

The U.S. Department of Energy (DOE) and the Pacific Northwest National Laboratory in collaboration with the Andronikashvili Institute of Physics in Tbilisi, Georgia have developed and tested technologies which sample contaminated areas inside hot cell facilities. Sampling locations in the facility include drains, ventilation exhaust ducts, sumps and shielded waste tanks. Tool designs for sampling each location include the ability to introduce the tool using existing ports, pass-throughs or inter-cells trolley and operate the tool with the existing remote manipulators. Areas inside the hot cell facility that would likely be contaminated from chemically processing irradiated reactor targets and fuel even after decontamination have been identified as potential sampling locations. Andronikashvili Institute of Physics in Tbilisi, Georgia has access to a reactor, hot cells, glove boxes and storage facilities that have been used to develop and test hot cell sampling technologies. These facilities are uncontaminated with radiological material and provide the ability to test these sampling technologies on representative equipment without contaminating the tools. Prototype tools have been fabricate and tested at these facilities using simulants representative of radiological contamination and waste.

Rostomashvili, Z.↗
DOE OSTI2016

Molecular Simulation of Cesium Adsorption at the Basal Surface of Phyllosilicate Minerals

A better understanding of the thermodynamics of radioactive cesium uptake at the surfaces of phyllosilicate minerals is needed to understand mechanisms of its selective adsorption and help guide the development of practical and inexpensive decontamination techniques. In this work, molecular dynamics simulations were carried out to determine the thermodynamics of adsorption of Cs + at the basal surface of six 2:1 phyllosilicate minerals, namely pyrophyllite, illite, muscovite, phlogopite, celadonite, and margarite. These minerals were selected to isolate the effects of the magnitude of the permanent layer charge (≤ 2), its location (tetrahedral versus octahedral sheet), and the structure of the octahedral sheet (dioctahedral versus trioctahedral). Good agreement was obtained with experiment in terms of the hydration free energy of Cs + and the structure and thermodynamics of Cs + adsorption at the muscovite basal surface, for which published data were available for comparison. With the exception of pyrophyllite, which did not exhibit an inner-sphere free energy minimum, all phyllosilicate minerals showed similar behavior with respect to Cs + adsorption; notably, Cs + adsorption was predominantly inner-sphere whereas outer-sphere adsorption was very weak with the simulations predicting the formation of an extended outer-sphere complex. For a given location of the layer charge, the free energy of adsorption as an inner-sphere complex was found to vary linearly with the magnitude of the layer charge. For a given location and magnitude of the layer charge, adsorption at phlogopite (trioctahedral sheet structure) was much less favorable than at muscovite (dioctahedral sheet structure) due to the electrostatic repulsion between the adsorbed Cs + and the hydrogen atom of the hydroxyl group directly below the six-membered siloxane ring cavity. For a given magnitude of the layer charge and structure of the octahedral sheet, adsorption at celadonite (layer charge located in the octahedral sheet) was favored over muscovite (layer charge located in the tetrahedral sheet) due to the increased distance with surface potassium ions.

(001) surface↗
DOE OSTI2017

An Assessment of Fission Product Scrubbing in Sodium Pools Following a Core Damage Event in a Sodium Cooled Fast Reactor

The U.S. Nuclear Regulatory Commission has stated that mechanistic source term (MST) calculations are expected to be required as part of the advanced reactor licensing process. A recent study by Argonne National Laboratory has concluded that fission product scrubbing in sodium pools is an important aspect of an MST calculation for a sodium-cooled fast reactor (SFR). To model the phenomena associated with sodium pool scrubbing, a computational tool, developed as part of the Integral Fast Reactor (IFR) program, was utilized in an MST trial calculation. This tool was developed by applying classical theories of aerosol scrubbing to the decontamination of gases produced as a result of postulated fuel pin failures during an SFR accident scenario. The model currently considers aerosol capture by Brownian diffusion, inertial deposition, and gravitational sedimentation. The effects of sodium vapour condensation on aerosol scrubbing are also treated. This paper provides details of the individual scrubbing mechanisms utilized in the IFR code as well as results from a trial mechanistic source term assessment led by Argonne National Laboratory in 2016.

Fission Product Scrubbing↗
DOE OSTI2016

Disposition of Chicago Pile 5 (CP-5) Converter Tubes in the 10-160B Cask

This paper will focus on the unique characterization, packaging, and transportation issues associated with the disposition of the two CP-5 Converter Tube assemblies from Argonne National Laboratory. The converter tubes were constructed of combinations of HEU and alloys of zirconium, and were part of the original research facilities attached to the CP-5 reactor during operating evolutions. These assemblies were heavily irradiated during their operational lifetime, and were segregated from the balance of irradiated test specimens when the reactor was deactivated and slated for Decontamination and Demolition (D&D). In addition, the substantial contribution of fissile material to the assemblies’ inventory made the potential disposition pathways extremely challenging. As a result, these items became part of Argonne’s legacy “nuclear footprint”, and were added to the Nuclear Footprint Reduction Project scope for disposition. The Project was responsible for the size reduction and characterization of these items, as well as the ultimate disposition. After negotiating a disposal pathway for these tubes, there were significant transportation issues that required a small team to overcome, in order to successfully ship these items to the Nevada National Security Site (NNSS). The Project team at Argonne, technical support from transportation specialists, licensing support from the 10-160B license owner, the Savanah River National Lab (SRNL) Packaging Certification Team (PCT, and the DOE EM-33 staff contributed to license and safety analysis report amendments that eventually authorized the shipment of the material. The paper will identify the organizations, and the specific actions, required to successfully make three “one of a kind” shipments of irradiated test specimen material. This will include the unique packaging configurations, contents modification for the cask license (via the Amendment process), criticality evaluations, and associated review and approval processes.

CP-5↗
DOE OSTI2019

FX2 Fogging Fixative Deployment for Radioactive Contamination Control

Idaho National Laboratory’s FX2 fixative solution was deployed as part of the decontamination and decommissioning (D&D) of an alpha-contaminated glovebox. The fixative was dispensed via fogging. The goal of the deployment was to reduce friable alpha radioactive contamination prior to removal of the glovebox. Information about the deployment and the efficacy of the treatment is presented.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

Compounds for reactivation of acetylcholinesterase and related compositions methods and systems

Described herein are oxime compounds capable of inactivating a nerve agent, blood brain barrier (BBB)-penetration, and/or reactivation of nerve agent-inhibited acetylcholinesterase (AChE) and related methods, systems and compositions for inactivation of one or more nerve agents, therapeutic and/or prophylactic treatment of an individual, and/or decomposition of nerve agent for decontamination.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

EBR-II Driver Fuel Cladding Hull Analytical Data

Sharing EBR-II driver fuel cladding hull data with General Atomics under NDA No. 20NDA155. Data share is needed to advance discussions regarding process technologies to decontaminate separated cladding hulls

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗
DOE OSTI2021

BERYLLIUM DETECTION BY FLUORESCENT SPECTROSCOPY

Facilities that machine and process materials involving beryllium oxide are hazardous to workers safety and require monitoring of contamination. A primary goal in industrial worker safety in beryllium containing facilities is avoiding inhalation, which may cause chronic beryllium disease (CBD). Decontamination is labor intensive due to the miniscule size of beryllium dust and the difficulty of detecting its presence on surfaces. Current methods of beryllium detection, while successful, involve numerous intermediate steps such as obtaining wipe samples, applying buffers, centrifuging with ammonium bifluoride, additives to reduce influence of other competing metal ions, and require potentially long wait times of around 24 hours for a single surface sample. In some cases, these samples must be sent to testing facilities across the country and results may not be available for days. Therefore, for the purposes of this study, it has been deemed important to test new fluorescent dyes that can rapidly produce a beryllium presence confirmation via application spray.

61 RADIATION PROTECTION AND DOSIMETRY↗
DOE OSTI2021

Compounds for central reactivation of organophosphorus-based compound-inhibited acetylcholinesterase and/or inactivation of organophosphorus-based acetylcholinesterase inhibitors and related compositions methods and systems for making and using them

Described herein are oxime compounds capable of inactivating OP-based AChE inhibitors, crossing the blood brain barrier (BBB), and/or reactivation of OP-inhibited acetylcholinesterase (AChE) and related methods, systems and compositions for inactivation of one or more OP-based AChE inhibitors, therapeutic and/or prophylactic treatment of an individual, and/or decomposition of OP-based AChE inhibitors for decontamination.

Valdez, Carlos A.↗