Surface changes of alternative cement matrices in a water environment over two years for their application in a deep repository for radioactive waste storage

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F26722445%3A_____%2F24%3AN0000208" target="_blank" >RIV/26722445:_____/24:N0000208 - isvavai.cz</a>

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Surface changes of alternative cement matrices in a water environment over two years for their application in a deep repository for radioactive waste storage

Popis výsledku v původním jazyce

A two-year study was initiated to investigate alternative materials for storing radioactive waste generated from the decommissioning of nuclear facilities in the Czech Republic. The proposed materials (matrices) should act as a chemical barrier reducing the migration of radionuclides, inhibit the corrosion of metallic waste (e.g., steel), and have a suitable mineral composition that warrant their long-term stability. Four matrices were studied: 1) cement CEM I, 2) geopolymer, 3) alternative filling matrix (CEM I + bentonite), and 4) nano-based matrix (cement CEM I+ 1% nanoiron). Two parallel experiments were designed, the first one to test the stability of the matrices under porewater (synthetic water simulating underground water); the second to test the corrosion of the steel pieces – corrosion coupons embedded in the matrices, where the matrices were enclosed in synthetic granitic water and stored under argon atmosphere. In the present work, we focus on the superficial changes of the matrices after being under different water environments for 0.5, 1, and 2 years, and monitor the corrosion of the embedded steel pieces (Fig. 1). Changes in mineral composition were monitored using X-ray diffraction both on the surface and at the interface of the steel and its corresponding matrix. Additionally, GIXRD was employed. Poster at The 18th European Powder Diffraction Conference, Padova, 30. 8. 2024 – 2. 9. 2024.

Název v anglickém jazyce

Surface changes of alternative cement matrices in a water environment over two years for their application in a deep repository for radioactive waste storage

Popis výsledku anglicky

A two-year study was initiated to investigate alternative materials for storing radioactive waste generated from the decommissioning of nuclear facilities in the Czech Republic. The proposed materials (matrices) should act as a chemical barrier reducing the migration of radionuclides, inhibit the corrosion of metallic waste (e.g., steel), and have a suitable mineral composition that warrant their long-term stability. Four matrices were studied: 1) cement CEM I, 2) geopolymer, 3) alternative filling matrix (CEM I + bentonite), and 4) nano-based matrix (cement CEM I+ 1% nanoiron). Two parallel experiments were designed, the first one to test the stability of the matrices under porewater (synthetic water simulating underground water); the second to test the corrosion of the steel pieces – corrosion coupons embedded in the matrices, where the matrices were enclosed in synthetic granitic water and stored under argon atmosphere. In the present work, we focus on the superficial changes of the matrices after being under different water environments for 0.5, 1, and 2 years, and monitor the corrosion of the embedded steel pieces (Fig. 1). Changes in mineral composition were monitored using X-ray diffraction both on the surface and at the interface of the steel and its corresponding matrix. Additionally, GIXRD was employed. Poster at The 18th European Powder Diffraction Conference, Padova, 30. 8. 2024 – 2. 9. 2024.

Druh

O - Ostatní výsledky

CEP obor

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OECD FORD obor

10402 - Inorganic and nuclear chemistry

Projekt

<a href="/cs/project/FW01010115" target="_blank" >FW01010115: ALternativní výplňové MAtrice pro ukládání RAdioaktivních odpadů z vyřazování jaderných elektráren (ALMARA)</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2024

Kód důvěrnosti údajů

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