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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Glass strategy: Hanford’s enhanced waste glass program
The mission of the Department of Energy’s Office of River Protection (ORP) is to complete the safe cleanup of waste resulting from decades of nuclear weapons development. One of the most technologically challenging responsibilities is the safe disposition of approximately 56 million gallons of radioactive waste historically stored in 177 tanks at the Hanford Site in Washington state.
ORP has a clear incentive to reduce the overall mission duration and cost. One pathway is to develop and deploy innovative technical solutions that can advance baseline flow sheets toward higher efficiency operations while reducing identified risks without compromising safety. Vitrification is the baseline process that will convert both high-level and low-level radioactive waste at Hanford into a stable glass waste form for long-term storage and disposal.
Although vitrification is a mature technology, there are key areas where technology can further reduce operational risks, advance baseline processes to maximize waste throughput, and provide the underpinning to enhance operational flexibility; all steps in reducing mission duration and cost.
Acacia Brunett, Richard Denning, Tunc Aldemir
Nuclear Technology | Volume 186 | Number 2 | May 2014 | Pages 198-215
Technical Paper | Reactor Safety | doi.org/10.13182/NT13-40
Articles are hosted by Taylor and Francis Online.
The risk-dominant containment failure modes of a pressurized water reactor are reassessed using the current state of knowledge for the phenomena that contribute to these failure modes. Our review concludes that some mechanisms that were considered as having the potential to result in containment failure at the time of NUREG-1150, such as in-vessel steam explosions and vessel launch (i.e., the alpha-mode containment failure), have subsequently undergone sufficient review and can be excluded from further consideration. For other phenomena, such as high-pressure melt ejection (HPME) and combustible gas explosions, our review concludes that substantial uncertainties still exist with regard to modeling in system level codes; for combustion events, careful consideration is still required when making severe accident management decisions. With regard to HPME, sensitivity studies have been performed with the MELCOR computer code to address the effects of modeling uncertainties on containment loading. Sensitivity studies using MELCOR have also been performed with regard to combustion events to examine gas generation, the effect of containment cooling on the potential for deflagrations, and the combustion load on containment. Combustion loads are compared to the NUREG-1150 containment fragility curve to assess the likelihood of containment failure. Our MELCOR analyses agree with the NUREG-1150 assumption that insufficient hydrogen is generated in-vessel to result in containment failure. Sensitivity studies regarding the rate and timing of reflooding a degraded core do not indicate a significant effect on hydrogen production in-vessel or a significant challenge to containment integrity regarding HPME. However, it is observed that recovery actions resulting in cooling of the containment atmosphere could result in deinerting the containment and lead to a sufficiently energetic combustion event that can fail the containment.