Coupled mixed-potential and thermal-hydraulics model for long-term corrosion of copper canisters in deep geological repository

Canister performance is a major issue for constructing reliable deep geological repositories for storing spent nuclear fuels, and corrosion resistance is main the factor determining canister durability. We developed a 2-D multiphysics model, which can predict both the corrosion rate and potential, for simulating copper canister corrosion in deep geological repositories. We found that canisters corroded through the long-cell action in a deep geological repository, the corrosion was quite limited, and the overall canister durability was around 1.7 million years. Our results demonstrated that copper exhibits sufficient corrosion resistance and that long-cell action-based corrosion cannot severely damage copper canisters.

Automated summary

Canister performance is crucial for reliable deep geological repositories storing spent nuclear fuels, and corrosion resistance determines canister durability. A 2-D multiphysics model was developed to predict copper canister corrosion rate and potential in deep geological repositories. The corrosion through long-cell action was limited, demonstrating copper's sufficient corrosion resistance and canister durability of approximately 1.7 million years.