Hydro-mechanical response to gas transfer of deep argillaceous host rocks for radioactive waste disposal

During recent decades, argillaceous sedimentary formations have been studied as potential host formations for the geological disposal of long-living and heat-emitting radioactive waste—Boom Clay in Belgium and Opalinus Clay and Brown Dogger in Switzerland. A significant issue in the long-term perfor...

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Detalhes bibliográficos
Autores: González Blanco, Laura|||0000-0003-3800-3007, Romero Morales, Enrique Edgar|||0000-0002-4105-8941, Marschall, Paul, Levasseur, Severine
Formato: artículo
Fecha de publicación:2022
País:España
Recursos:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/360215
Acesso em linha:https://hdl.handle.net/2117/360215
https://dx.doi.org/10.1007/s00603-021-02717-3
Access Level:acceso abierto
Palavra-chave:Radioactive waste disposal in the ground
Gas dynamics
Rocks--Analysis
Analytical geochemistry
Rocks--Permeability
Deep geological repository
Coupled process
Gas transfer
Hydro-mechanical behaviour
Argillaceous rocks
Laboratory tests
Geoquímica analítica
Dinàmica de gasos
Àrees temàtiques de la UPC::Física
Descrição
Resumo:During recent decades, argillaceous sedimentary formations have been studied as potential host formations for the geological disposal of long-living and heat-emitting radioactive waste—Boom Clay in Belgium and Opalinus Clay and Brown Dogger in Switzerland. A significant issue in the long-term performance of these potential host rocks concerns the generation and transport of gases. The pressure resulting from the generation of gas in an almost impermeable geological medium in the near field of a repository will increase. Under high gas pressures, the mechanical and hydraulic properties of the host rock are expected to change significantly. Preferential gas pathways may develop which exploit material heterogeneity, anisotropy (bedding planes), rock discontinuities, or interfaces between the different components of the repository, and may eventu- ally lead to the release of the produced gases. Gas flow through these clayey rocks is investigated on the basis of laboratory work. Priority has been given to studying the volume change response of these initially water-saturated materials through relatively fast and controlled volume-rate gas injections. The effect of the gas injection rate, the confining pressure and the bedding orientation on the gas transport properties have been studied with particular attention paid to the coupling with strain behaviour. The results have shown features common to the three formations concerning the gas transfer process through preferential pathways, despite their initially differential properties.