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Multinuclear NMR Monitoring of Decontamination Chemistries of Bulk Chemical Agents and Simulants.
Abstract not provided.
Challenges in the Decontamination of Chemical and Biological Warfare Agents and Other Biological Pathogens.
Abstract not provided.
Superabsorbing gel for actinide, lanthanide, and fission product decontamination
The present invention provides an aqueous gel composition for removing actinide ions, lanthanide ions, fission product ions, or a combination thereof from a porous surface contaminated therewith. The composition comprises a polymer mixture comprising a gel forming cross-linked polymer and a linear polymer. The linear polymer is present at a concentration that is less than the concentration of the cross-linked polymer. The polymer mixture is at least about 95% hydrated with an aqueous solution comprising about 0.1 to about 3 percent by weight (wt %) of a multi-dentate organic acid chelating agent, and about 0.02 to about 0.4 molar (M) carbonate salt, to form a gel. When applied to a porous surface contaminated with actinide ions, lanthanide ions, and/or other fission product ions, the aqueous gel absorbs contaminating ions from the surface.
Decontamination of tritiated water
Methods and systems directed to the separation of tritium from an aqueous stream are described. The separation method is a multi-stage method that includes a first stage during which tritium of a tritium-contaminated aqueous stream is adsorbed onto a separation phase, a second stage during which the adsorbed tritium is exchanged with hydrogen in a gaseous stream to provide a gaseous stream with a high tritium concentration, and a third stage during which the tritium of the gaseous stream is separated from the gaseous stream as a gaseous tritium product.
Customized Instructory Guide Lab Biorisk Managment - Focus on MC&A Good Lab Practices & Decontamination.
Abstract not provided.
Decontamination Strategy and Technology Selection Tool - TaCBRD TD3 Orientation Slides.
Abstract not provided.
A Proposed Methodology for Estimating Decontamination Costs in MACCS 3.10.
Abstract not provided.
Decontamination of tritiated water
Methods and systems directed to the separation of tritium from an aqueous stream are described. The separation method is a multi-stage method that includes a first stage during which tritium of a tritium-contaminated aqueous stream is adsorbed onto a separation phase, a second stage during which the adsorbed tritium is exchanged with hydrogen in a gaseous stream to provide a gaseous stream with a high tritium concentration, and a third stage during which the tritium of the gaseous stream is separated from the gaseous stream as a gaseous tritium product.
In-Between-Patient Decontamination of CT Rooms and Equipment Following COVID-19 Exposure Using Pulsed Plasma Activated Fog
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Rapid Beryllium Analysis to Expedite Decontamination
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Dual Mode Air Plasma Decontamination System
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Radioactive Contamination Tenacity on Building Substrate – 17417
Radiological decontamination is an essential enterprise that has become more important over the last four decades due to unfortunate accidents and the threat of terrorist actions. Decontamination can be an effective, beneficial alternative for the cleanup of radiological contamination events; however, the costs and benefits need to be balanced against those for complete removal and demolition of contaminated areas or facilities. Demolition and removal are often the first options considered in such circumstances as decontamination may be thought of as slow and costly. Decontamination has advantages, including significant waste reduction over demolition. In areas with buildings of cultural or societal importance, demolition may not be an option. Three decontamination evaluation test series are the focus of this article: SIMCON 1 and 2 (i.e., simulated contamination), and Urban RDD (radiological dispersal device, i.e., a dirty bomb detonation). These test series revealed that different contaminants respond differently during decontamination. This was found to be true with both SIMCON and Urban RDD simulant tests. SIMCON 2 especially demonstrated that chemically different contaminants respond differently to different decontamination methods: cesium appears to be less tenacious (more easily removed) than zirconium using chemical methods. These differences were underscored by the Urban RDD tests where americium and cobalt tended to precipitate on high pH surfaces (such as concrete), making them easier to remove, while cesium and strontium were essentially unaffected by surface pH and were imbibed more strongly into the substrate pore structure. While authorities argue over the contributions of contaminant chemistry and substrate morphology, the clear answer is that each has a contribution to the tenacity of a contaminant. Knowing how these characteristics interact will make us better at decontamination in the field. This knowledge refutes the efforts of perhaps well-meaning marketers to define our decontamination problems by what products they are trying to sell; often a “one size fits all” type approach. Knowing even a little bit about the character of the decontamination problem will save time and money and increase the efficacy of decontamination.
Radioactive Contamination Tenacity on Building Substrate - 17417
Radiological decontamination is an essential enterprise that has become more important over the last four decades due to unfortunate accidents and the threat of terrorist actions. Decontamination can be an effective, beneficial alternative for the cleanup of radiological contamination events; however, the costs and benefits need to be balanced against those for complete removal and demolition of contaminated areas or facilities. Demolition and removal are often the first options considered in such circumstances as decontamination may be thought of as slow and costly. Decontamination has advantages, including significant waste reduction over demolition. In areas with buildings of cultural or societal importance, demolition may not be an option. Three decontamination evaluation test series are the focus of this article: SIMCON 1 and 2 (i.e., simulated contamination), and Urban RDD (radiological dispersal device, i.e., a dirty bomb detonation). These test series revealed that different contaminants respond differently during decontamination. This was found to be true with both SIMCON and Urban RDD simulant tests. SIMCON 2 especially demonstrated that chemically different contaminants respond differently to different decontamination methods: cesium appears to be less tenacious (more easily removed) than zirconium using chemical methods. These differences were underscored by the Urban RDD tests where americium and cobalt tended to precipitate on high pH surfaces (such as concrete), making them easier to remove, while cesium and strontium were essentially unaffected by surface pH and were imbibed more strongly into the substrate pore structure. While authorities argue over the contributions of contaminant chemistry and substrate morphology, the clear answer is that each has a contribution to the tenacity of a contaminant. Knowing how these characteristics interact will make us better at decontamination in the field. This knowledge refutes the efforts of perhaps well-meaning marketers to define our decontamination problems by what products they are trying to sell; often a 'one size fits all' type approach. Knowing even a little bit about the character of the decontamination problem will save time and money and increase the efficacy of decontamination. (authors)
Sorption of radionuclides to building materials and its removal using simple salts - 15452
Decontamination after a nuclear or radiological release requires a detailed understanding of the materials hosting the contamination, the chemistry of the radionuclide, and the chemical properties of the decontamination agent. We have been studying the sorption chemistry of cesium onto urban building materials and roadways to develop simple decontamination methods that can be deployed for wide-area decontamination efforts. Our results include sorption/desorption of these radionuclides onto specific minerals found in some concrete and brick, and from monolithic coupons of concrete, asphalt, marble, tile, and brick as a function of time, age of contamination, and salt composition of the decontamination solutions. For example, we found that both the fine and coarse aggregate of concrete sorb cesium very well, and its desorption is much improved using 0.5 M ammonium-based salts than at lower concentrations. Decontamination of cesium from asphalt was much improved when a surfactant was added to the salt to improve the wettability of the decontamination solution (40% removal compared to <20% when only salt was present in the solution). Decontamination of powdered cesium is significantly higher when salt is present (>80% removed) compared to tap water washes (40% removal) although we found no difference in the decontamination from asphalt. We have also tested the re-adsorption of these radionuclides from the decontamination solution onto solid supports to facilitate waste disposal and minimize collateral environmental contamination. For example, in ammonium solutions, montmorillonite clay sorbs cesium poorly, but vermiculite clay can remove >90% of the cesium at 0.5 M NH{sub 4}{sup +}. With these results, we have been able to recommend simple salt solutions that can be effective on certain radioactive contaminations. These methods may be applicable to self-help activities in addition to wide-area decontamination efforts. (authors)
Metallic Low-Level Waste (LLW) Handling Options: An Optimal Life cycle-Based Approach for North American Operations - 19413
Daily activities associated with nuclear power plant operations produce large volumes of low-level contaminated waste. During operation, a small percentage of this low-level waste is metallic (< 1% by volume). However, this figure increases materially when a facility is finally decommissioned, with approximately 1000 m{sup 3} of contaminated metal waste generated for every 1 GW decommissioned (13% by volume). With global nuclear decommissioning efforts expected to increase until 2050, the amount of low-level metallic waste generated is expected to increase the global inventory by over an order of magnitude. The high cost of conventional surface storage and burial of radioactive metal, coupled with the projected increase in low-level metallic waste volumes provides strong incentive to identify cost-effective waste management solutions. Surface decontamination and thermal methods are proven options for decontaminating low-level metallic waste. Surface decontamination processes include chemical, electrochemical, or mechanical methods, which are used to remove contamination from exposed layers of metal. Surface decontamination is most effective when metal has low levels of activity localized on the outer layers. When the activity is more uniformly distributed in the metal (or the geometry is complex), alternative methods such as thermal decontamination are required. In the thermal decontamination process, contaminated scrap metal is melted in a furnace and held in a molten state for a period of time while the radioactive material is separated out through gravity. Radioactive material reports to slag which is handled separately, or to the exhaust which is handled using conventional gas handling technologies. Thermal methods of decontamination involving metal melting present an opportunity to reduce long-term storage cost with a reduction in waste volume, along with the opportunity to reuse the decontaminated metal. Methods for dealing with metallic low-level waste from nuclear facilities vary extensively across the globe. The approach employed at any given site may be set by a host of factors ranging from regulatory influence, public perception, local economics, available geology for underground storage and often, precedent established long ago by early operations. This paper examines several low-level metallic waste handling options including techniques for surface decontamination and metal melting, as well as a combination of both. The various methods are categorized according to their suitability for waste characterization and local/global installations. The effectiveness of each option is benchmarked against a range of criteria, including capital and operating costs, environmental impact, overall sustainability and risk management issues. The overall objective of this paper is to develop a methodology for determining the most beneficial low-level metallic waste management strategy for a facility once the quantity, type and nature of the waste is established on a long-term basis. It is the authors' hope that the methodology can be used as a tool to test a facility's current plans (which are primarily focused on long-term storage) and identify areas for optimization with an emphasis on overall cost and environmental footprint reduction. The trend towards long term planning to handle large amounts of contaminated metal, along with obtaining a social license to implement a sustainable waste management solution, are key decision-making variables that will be discussed in relation to the LLW handling options presented in this paper. (authors)