Nuclear Engineering and Technology

Korean Nuclear Society (한국원자력학회)
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Investigation of the various properties of several candidate additives as buffer materials

  • Gi-Jun Lee (Disposal Safety Evaluation Research Division, Korea Atomic Energy Research Institute (KAERI)) ;
  • Seok Yoon (Disposal Safety Evaluation Research Division, Korea Atomic Energy Research Institute (KAERI)) ;
  • Taehyun Kim (Disposal Performance Demonstration on Research Division, Korea Atomic Energy Research Institute (KAERI)) ;
  • Seeun Chang (Disposal Safety Evaluation Research Division, Korea Atomic Energy Research Institute (KAERI))
  • Received : 2022.08.04
  • Accepted : 2022.11.21
  • Published : 2023.03.25
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Abstract

Bentonite buffer material is a critical component in an engineered barrier system (EBS) for disposing high-level radioactive waste (HLW). The bentonite buffer material protects the disposal canister from groundwater penetration and releases decay heat to the surrounding rock mass; thus, it should possess high thermal conductivity, low hydraulic conductivity, and moderate swelling pressure to safely dispose the HLWs. Bentonite clay is a suitable buffer material because it satisfies the safety criteria. Several additives have been suggested as mixtures with bentonite to increase the thermal-hydraulic-mechanical-chemical (THMC) properties of bentonite buffer materials. Therefore, this study investigated the geotechnical, mineralogical, and THMC properties of several candidate additives such as sand, graphite, granite, and SiC powders. Datasets obtained in this study can be used to select adequate additives to improve the THMC properties of the buffer material.

Keywords

Acknowledgement

This research was funded by the Nuclear Research and Development Program (2021M2E3A2041351) by the National Research Foundation of Korea, and Institute for Korea Spent Nuclear Fuel and National Research Foundation of Korea (2021M2E1A1085193).

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