Foaming during nuclear waste melter feeds conversion to glass: Application of evolved gas analysis

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60461373%3A22310%2F18%3A43917162" target="_blank" >RIV/60461373:22310/18:43917162 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/67985891:_____/18:00497147

Výsledek na webu

<a href="https://onlinelibrary.wiley.com/doi/full/10.1111/ijag.12353" target="_blank" >https://onlinelibrary.wiley.com/doi/full/10.1111/ijag.12353</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1111/ijag.12353" target="_blank" >10.1111/ijag.12353</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Foaming during nuclear waste melter feeds conversion to glass: Application of evolved gas analysis

Popis výsledku v původním jazyce

During the final stages of batch-to-glass conversion in a waste-glass melter, gases evolving in the cold cap produce primary foam, the formation and collapse of which control the glass production rate via its effect on heat transfer to the reacting batch. We performed quantitative evolved gas analysis (EGA) for several HLW melter feeds with temperatures ranging from 100 to 1150°C, the whole temperature span in a cold cap. EGA results were supplemented with visual observation of batch-to-glass transition using the feed expansion tests. Upon heating, most of the gases mainly H2O, CO2, NO, NO2, N-2, and O(2)evolve at temperatures below 700°C and escape directly to the atmosphere through open porosity. However, as open porosity closes when enough glass-forming melt appears at 720°C, the residual gas evolution leads to the formation of primary foam. We found that primary foaming is mostly caused by the decomposition of residual carbonates, though oxygen evolution from iron-redox reaction can also play a role. We also show that the gas evolution shifts to a higher temperature when the heating rate increases. The implications for the mathematical modeling of foam layer in the cold cap are presented.

Název v anglickém jazyce

Foaming during nuclear waste melter feeds conversion to glass: Application of evolved gas analysis

Popis výsledku anglicky

During the final stages of batch-to-glass conversion in a waste-glass melter, gases evolving in the cold cap produce primary foam, the formation and collapse of which control the glass production rate via its effect on heat transfer to the reacting batch. We performed quantitative evolved gas analysis (EGA) for several HLW melter feeds with temperatures ranging from 100 to 1150°C, the whole temperature span in a cold cap. EGA results were supplemented with visual observation of batch-to-glass transition using the feed expansion tests. Upon heating, most of the gases mainly H2O, CO2, NO, NO2, N-2, and O(2)evolve at temperatures below 700°C and escape directly to the atmosphere through open porosity. However, as open porosity closes when enough glass-forming melt appears at 720°C, the residual gas evolution leads to the formation of primary foam. We found that primary foaming is mostly caused by the decomposition of residual carbonates, though oxygen evolution from iron-redox reaction can also play a role. We also show that the gas evolution shifts to a higher temperature when the heating rate increases. The implications for the mathematical modeling of foam layer in the cold cap are presented.

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

2018

Kód důvěrnosti údajů

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

Název periodika

International Journal of Applied Glass Science

ISSN

2041-1286

e-ISSN

—

Svazek periodika

9

Číslo periodika v rámci svazku

4

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

12

Strana od-do

487-498

Kód UT WoS článku

000443390700004

EID výsledku v databázi Scopus

2-s2.0-85045843375