Melting behaviour of simulated radioactive waste as functions of different redox iron-bearing raw materials

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985891%3A_____%2F22%3A00562746" target="_blank" >RIV/67985891:_____/22:00562746 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/60461373:22310/22:43925588

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0022311522004329" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0022311522004329</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.jnucmat.2022.153946" target="_blank" >10.1016/j.jnucmat.2022.153946</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Melting behaviour of simulated radioactive waste as functions of different redox iron-bearing raw materials

Popis výsledku v původním jazyce

Improved understanding of the mechanisms by which foaming occurs during vitrification of high-level radioactive waste feeds prior to operation of the Waste Treatment and Immobilization Plant at the Hanford Site, USA, will help to obviate operational issues and reduce the duration of the clean-up project by enhancing the feed-to-glass conversion. The HLW-NG-Fe2 high-iron simulated waste feed has been shown to exhibit excessive foaming, and the most recent predictive models overestimate the feed melting rate. The influence of delivering iron as a Fe2+-bearing raw material (FeC2O4 center dot 2H(2)O), rather than a Fe3+ (Fe(OH)(3)) material, was evaluated in terms of the effects on foaming during melting, to improve understanding of the mechanisms of foam production. A decrease of 50.0 +/- 10.8% maximum generated foam volume is observed using FeC2O4 center dot 2H(2)O as the iron source, compared with Fe(OH)(3). This is determined to be due to a large release of CO2 before the foam onset temperature (the temperature above which the liquid phases forming are sufficiently viscous to trap the gases) and suppression of O-2 evolution during foam collapse. Structural analyses of simulated waste feeds after different stages of melting show that the remaining Fe2+ in the modified feed is oxidised to Fe3+ at temperatures between 600 and 800 degrees C. This feed was tested in a Laboratory Scale Melter with no excessive foaming or feeding issues. Analysis of the final glass products indicates that the glasses produced using the original HLW-NG-Fe-2 feed using Fe(OH)(3) and the feed made with FeC2O4 center dot 2H(2)O are structurally similar but not identical: the difference in the structure converges when the glass is melted for 24 h, suggesting a transient structure slightly different to that of the baseline in the glass produced using the reduced raw material. (c) 2022 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)

Název v anglickém jazyce

Melting behaviour of simulated radioactive waste as functions of different redox iron-bearing raw materials

Popis výsledku anglicky

Improved understanding of the mechanisms by which foaming occurs during vitrification of high-level radioactive waste feeds prior to operation of the Waste Treatment and Immobilization Plant at the Hanford Site, USA, will help to obviate operational issues and reduce the duration of the clean-up project by enhancing the feed-to-glass conversion. The HLW-NG-Fe2 high-iron simulated waste feed has been shown to exhibit excessive foaming, and the most recent predictive models overestimate the feed melting rate. The influence of delivering iron as a Fe2+-bearing raw material (FeC2O4 center dot 2H(2)O), rather than a Fe3+ (Fe(OH)(3)) material, was evaluated in terms of the effects on foaming during melting, to improve understanding of the mechanisms of foam production. A decrease of 50.0 +/- 10.8% maximum generated foam volume is observed using FeC2O4 center dot 2H(2)O as the iron source, compared with Fe(OH)(3). This is determined to be due to a large release of CO2 before the foam onset temperature (the temperature above which the liquid phases forming are sufficiently viscous to trap the gases) and suppression of O-2 evolution during foam collapse. Structural analyses of simulated waste feeds after different stages of melting show that the remaining Fe2+ in the modified feed is oxidised to Fe3+ at temperatures between 600 and 800 degrees C. This feed was tested in a Laboratory Scale Melter with no excessive foaming or feeding issues. Analysis of the final glass products indicates that the glasses produced using the original HLW-NG-Fe-2 feed using Fe(OH)(3) and the feed made with FeC2O4 center dot 2H(2)O are structurally similar but not identical: the difference in the structure converges when the glass is melted for 24 h, suggesting a transient structure slightly different to that of the baseline in the glass produced using the reduced raw material. (c) 2022 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20504 - Ceramics

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2022

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Nuclear Materials

ISSN

0022-3115

e-ISSN

1873-4820

Svazek periodika

569

Číslo periodika v rámci svazku

OCT

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

21

Strana od-do

153946

Kód UT WoS článku

000864543400006

EID výsledku v databázi Scopus

2-s2.0-85135302153