Investigation of Radiolysis in Cement Pastes Immobilizing Simulated Evaporator Concrentrates

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F26722445%3A_____%2F21%3AN0000037" target="_blank" >RIV/26722445:_____/21:N0000037 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0306454920305983" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0306454920305983</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.anucene.2020.107901" target="_blank" >10.1016/j.anucene.2020.107901</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Investigation of Radiolysis in Cement Pastes Immobilizing Simulated Evaporator Concrentrates

Popis výsledku v původním jazyce

The waste management of radioactive evaporator concentrates (EC) in deep geological repositories requires safe immobilization in a solid matrix, such as cement composites. Radiolysis occurs inside the hydrated cement paste due to irradiation of either free or bonded water. As a result, the generation of hydrogen and the consequent pressure build-up within the material may pose safety risks within the geological repository. Three kinds of cement pastes sealed in steel containers were irradiated by gamma source Co-60 to achieve absorbed dose of 1.75 MGy simulating the conditions inside a repository. Specific binder matrix suitable for cement composites immobilizing EC marked as "NP" was studied, as well as the actual simulated immobilized waste (model concentrate) in the binder marked as "NP_C" and a reference paste "PC". Results showed an increase in pressure of generated gas from the irradiated samples up to 100 kPa. After 120 days of irradiation the reference paste reached steady state, while NP and NP_C continued in the rising trend. However, the absolute values of NP_C were lower than the values of the reference paste, probably due to the presence of dissolved salts in the model concentrates, especially nitrates. The maximum value reached does not present safety risks within the repository, moreover the presence of certain salts in the concentrate has a positive effect on the decrease of the rate and the final values of the pressure build-up.

Název v anglickém jazyce

Investigation of Radiolysis in Cement Pastes Immobilizing Simulated Evaporator Concrentrates

Popis výsledku anglicky

The waste management of radioactive evaporator concentrates (EC) in deep geological repositories requires safe immobilization in a solid matrix, such as cement composites. Radiolysis occurs inside the hydrated cement paste due to irradiation of either free or bonded water. As a result, the generation of hydrogen and the consequent pressure build-up within the material may pose safety risks within the geological repository. Three kinds of cement pastes sealed in steel containers were irradiated by gamma source Co-60 to achieve absorbed dose of 1.75 MGy simulating the conditions inside a repository. Specific binder matrix suitable for cement composites immobilizing EC marked as "NP" was studied, as well as the actual simulated immobilized waste (model concentrate) in the binder marked as "NP_C" and a reference paste "PC". Results showed an increase in pressure of generated gas from the irradiated samples up to 100 kPa. After 120 days of irradiation the reference paste reached steady state, while NP and NP_C continued in the rising trend. However, the absolute values of NP_C were lower than the values of the reference paste, probably due to the presence of dissolved salts in the model concentrates, especially nitrates. The maximum value reached does not present safety risks within the repository, moreover the presence of certain salts in the concentrate has a positive effect on the decrease of the rate and the final values of the pressure build-up.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20305 - Nuclear related engineering; (nuclear physics to be 1.3);

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2021

Kód důvěrnosti údajů

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

Název periodika

Annals of Nuclear Energy

ISSN

0306-4549

e-ISSN

—

Svazek periodika

151

Číslo periodika v rámci svazku

February

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

5

Strana od-do

1-5

Kód UT WoS článku

000595796000031

EID výsledku v databázi Scopus

2-s2.0-85092272330