Effect of cold cap coverage and emissivity on the plenum temperature in a pilot-scale waste vitrification melter

0534155 - ÚSMH 2021 RIV US eng J - Článek v odborném periodiku
Abboud, A.W. - Guillen, D.P. - Pokorný, Richard
Effect of cold cap coverage and emissivity on the plenum temperature in a pilot-scale waste vitrification melter.
International Journal of Applied Glass Science. Roč. 11, č. 2 (2020), s. 357-368. ISSN 2041-1286. E-ISSN 2041-1294
Institucionální podpora: RVO:67985891
Klíčová slova: computational fluid dynamics * heat transfer * melter * plenum * vitrification * waste glass
Obor OECD: Ceramics
Impakt faktor: 2.029, rok: 2020
Způsob publikování: Omezený přístup
https://ceramics-onlinelibrary-wiley-com.ezproxy.lib.cas.cz/doi/full/10.1111/ijag.15031

Integrated computational fluid dynamics (CFD) models are being developed to model the complex physics occurring within the high-level waste melter for vitrification of legacy tank waste at the Hanford site. This study presents a validation of the integrated CFD model by using data from two experimental runs in a pilot-scale melter. While the model uses several simplifying assumptions (such as constant heat sinks from a cooling jacket and inleakage of ambient air, steady state feed-to-batch conversion heat, and a cold cap model with a simplified shape), it closely predicts the molten glass (1150 degrees C and 1175 degrees C) and plenum temperatures (550 degrees C) obtained from thermocouples during two pilot-scale tests, with an average cold cap coverage of 80%. Additional simulations were performed to explore the sensitivity of the predicted plenum temperatures to variations in cold cap coverage (fraction of melt surface covered by the glass batch) and batch emissivity. The plenum temperature was found to be in the range of 606 degrees C when cold cap coverage decreased from 95% to 70%. Cold cap emissivity had a smaller effect, increasing the plenum temperature by as much as 179 degrees C when cold cap emissivity increased from 0.2 to 0.8. Maintaining a high cold cap coverage without overfeeding is important for a sustained melter operation with high glass throughput. This work provides a tool for achieving that goal in terms of correlating the plenum temperature with the cold cap coverage.
Trvalý link: http://hdl.handle.net/11104/0312393