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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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.
S. P. Congdon, M. R. Mendelson
Nuclear Science and Engineering | Volume 33 | Number 2 | August 1968 | Pages 151-161
Technical Paper | doi.org/10.13182/NSE68-A20653
Articles are hosted by Taylor and Francis Online.
The derivation of blackness boundary conditions is reviewed and generalized into a standard matrix formalism that is valid for any order PN approximation. It is then shown that for a finite slab effective diffusion and absorption matrices can be found which reproduce blackness boundary conditions at the interfaces. In the continuous or infinitely many mesh point description of the black region, the analysis leads to infinite series expressions for the equivalent matrices, which have been evaluated explicitly by means of the Caley-Hamilton theorem for the case of the P 3 approximation. Equivalent matrices have also been derived for two- and three-mesh-point descriptions of the black region. Numerical calculations for three model problems indicate that P3 blackness theory is a great improvement over conventional P3 theory and is roughly equivalent to P5 theory in the prediction of both the exterior scalar flux and the absorption rate in the black region.