Air and hydrogen injection tests on saturated compacted bentonite

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21110%2F23%3A00370140" target="_blank" >RIV/68407700:21110/23:00370140 - isvavai.cz</a>

Výsledek na webu

<a href="https://doi.org/10.59490/seg.2023.589" target="_blank" >https://doi.org/10.59490/seg.2023.589</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.59490/seg.2023.589" target="_blank" >10.59490/seg.2023.589</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Air and hydrogen injection tests on saturated compacted bentonite

Popis výsledku v původním jazyce

The concept of the Czech deep geological repository for radioactive waste, as in most other countries that are planning such projects, currently envisages the use of compacted bentonite for the sealing layer around the waste disposal package emplaced in the disposal borehole. The concept considered involves the use of steel-based waste disposal packages. It is expected that gases (mostly hydrogen) will form as a result of the corrosion of the waste disposal package, via the radiolysis of water or due to the development of microbial activity; therefore, a knowledge of the gas transport mechanisms in bentonite is fundamental in terms of the safety assessment of the deep geological repository. It is known that gas flow in water-saturated bentonite occurs mostly via networks of pressure-induced dilatant pathways, a fact that has been supported by the results of numerous laboratory tests involving indirect observations as well as direct detection methods. The current state of the art with concern to gas transport processes was established via the EURAD project [1]. This article presents the work carried out by the CTU in Prague and ÚJV Řež as part of Task 2 of the GAS Work Package of the EURAD project. Since the Czech deep geological repository concept is considering the use of local bentonites, the research programme is focusing on Czech Ca-Mg bentonite (BCV) and its benchmarking comparison with foreign materials such as MX-80 sodium bentonite. Both the CTU and ÚJV laboratory testing programmes involve the performance of gas breakthrough tests on water-saturated compacted bentonite samples using similar methodologies and equipment. The objective of the research is to compare the gas breakthrough behaviour of Czech bentonite with other materials. Moreover, the key contribution of the research concerns the direct use of hydrogen as the gas injection medium for some of the tests, thus providing unique data for comparison with other gases that are typically used as a surrogate for hydrogen.

Název v anglickém jazyce

Air and hydrogen injection tests on saturated compacted bentonite

Popis výsledku anglicky

The concept of the Czech deep geological repository for radioactive waste, as in most other countries that are planning such projects, currently envisages the use of compacted bentonite for the sealing layer around the waste disposal package emplaced in the disposal borehole. The concept considered involves the use of steel-based waste disposal packages. It is expected that gases (mostly hydrogen) will form as a result of the corrosion of the waste disposal package, via the radiolysis of water or due to the development of microbial activity; therefore, a knowledge of the gas transport mechanisms in bentonite is fundamental in terms of the safety assessment of the deep geological repository. It is known that gas flow in water-saturated bentonite occurs mostly via networks of pressure-induced dilatant pathways, a fact that has been supported by the results of numerous laboratory tests involving indirect observations as well as direct detection methods. The current state of the art with concern to gas transport processes was established via the EURAD project [1]. This article presents the work carried out by the CTU in Prague and ÚJV Řež as part of Task 2 of the GAS Work Package of the EURAD project. Since the Czech deep geological repository concept is considering the use of local bentonites, the research programme is focusing on Czech Ca-Mg bentonite (BCV) and its benchmarking comparison with foreign materials such as MX-80 sodium bentonite. Both the CTU and ÚJV laboratory testing programmes involve the performance of gas breakthrough tests on water-saturated compacted bentonite samples using similar methodologies and equipment. The objective of the research is to compare the gas breakthrough behaviour of Czech bentonite with other materials. Moreover, the key contribution of the research concerns the direct use of hydrogen as the gas injection medium for some of the tests, thus providing unique data for comparison with other gases that are typically used as a surrogate for hydrogen.

Druh

O - Ostatní výsledky

CEP obor

—

OECD FORD obor

20501 - Materials engineering

Projekt

—

Návaznosti

S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2023

Kód důvěrnosti údajů

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