한국지반공학회논문집 (Journal of the Korean Geotechnical Society)

  • 제37권4호
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  • Pages.19-26
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  • 2021
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  • 1229-2427(pISSN)
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  • 2288-646X(eISSN)
한국지반공학회 (Korean Geotechnical Society)
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고준위폐기물처분장 공학적방벽의 갭 공간이 미치는 영향 분석

An Influence Analysis on the Gap Space of an Engineered Barrier for an HLW Repository

  • 윤석 (한국원자력연구원 방사성폐기물처분연구부) ;
  • 이창수 (한국원자력연구원 방사성폐기물처분연구부) ;
  • 김민준 (한국지질자원연구원 심지층연구센터)
  • Yoon, Seok (Radioactive Waste Disposal Research Division, KAERI) ;
  • Lee, Changsoo (Radioactive Waste Disposal Research Division, KAERI) ;
  • Kim, Min-Jun (Deep Subsurface Research Center, KIGAM)
  • 투고 : 2021.02.19
  • 심사 : 2021.03.30
  • 발행 : 2021.04.30
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초록

원자력발전소에서 발생되는 고준위폐기물은 지하 수백 미터 깊이의 암반에 처분된다. 이러한 고준위폐기물은 인체에 유해하기에 공학적방벽시스템에 의해 안전하게 처분되어야 하며, 공학적방벽시스템은 처분용기, 뒤채움재, 완충재 등으로 구성된다. 고준위폐기물처분장에 이러한 공학적방벽시스템의 구성요소를 설치하게 되면, 처분용기 및 완충재 사이, 완충재와 자연 암반 사이 등에 갭이 존재하게 된다. 이러한 갭의 존재로 인해 공학적방벽재의 차수능과 열전달 효율이 떨어질 수 있기에, 갭 공간의 크기 및 갭채움재 특성 평가 등의 연구가 반드시 필요하다고 할 수 있다. 해외에 비해 국내 처분시스템을 고려한 갭 공간 및 갭채움재에 대한 연구는 아직 진행되고 있지 않는 상황이기에, 본 연구에서는 수치해석을 통해 국내 처분시스템을 고려한 갭 공간이 공기로 채워져 있는 조건하에서 갭의 크기에 따른 벤토나이트 완충재의 첨두 온도를 도출하였다. 처분용기와 완충재 사이의 갭 공간이 완충재의 첨두 온도에 미치는 영향은 미미하였으나, 완충재와 자연 암반 사이의 갭 공간에 따른 완충재의 첨두 온도는 최고 약 40%의 차이를 나타냈다.

The high-level radioactive waste (HLW) produced from nuclear power plants is disposed in a rock-mass at a depth of hundreds meters below the ground level. Since HLW is very dangerous to human being, it must be disposed of safely by the engineered barrier system (EBS). The EBS consists of a disposal canister, backfill material, buffer material, and so on. When the components of EBS are installed, gaps inevitably exist not only between the rock-mass and buffer material but also between the canister and buffer material. The gap can reduce water-retarding capacity and heat release efficiency of the buffer material, so it is necessary to investigate properties of gap-filling materials and to analyze gap spacing effect. Furthermore, there has been few researches considering domestic disposal system compared to overseas researches. In this reason, this research derived the peak temperature of the bentonite buffer material considering domestic disposal system based on the numerical analysis. The gap between the canister and buffer material had a minor effect on the peak temperature of the bentonite buffer material, but there was 40% difference of the peak temperature of the bentonite buffer material because of the gap existence between the buffer material and rock mass.

키워드

참고문헌

  1. Cengel, Y. A. and Ghajar, A. J. (2011), "Heat and Mass Transfer: Fundamentals and Applications", Fourth edition McGraw Hill Education.
  2. Chen, W. Z., Ma, Y. S., Yu, H. D., Li, F. F., Li, X. L., and Sillen, X. (2017), "Effects of Temperature and Thermally-induced Microstructure Change on Hydraulic Conductivity of Boom Clay", Journal of Rock Mechanics and Geotechnical Engineering, Vol.9, pp.383-395. https://doi.org/10.1016/j.jrmge.2017.03.006
  3. Cho, W. J. (2017), "Radioactive Waste Disposal", KAERI/GP-495/2017.
  4. Cho, W. J., Lee, J. O., and Chun, K. S. (1999), "The Temperature Effects on Hydraulic Conductivity of Compacted Bentonite", Applied Clay Science, Vol.14, pp.47-58. https://doi.org/10.1016/S0169-1317(98)00047-7
  5. Choi, H. J., Lee, J. Y., Kim, S. S., Kim, S. K., Cho, D. K., Kim, K. Y., Jeong, J. T., Jeon, K. S., Choi, J. W., Lee, J. O., Lee, M. S., and Kim, P. O. (2008), "Korean Reference HLW Disposal System", KAERI/TR-3563/2008.
  6. Comsol Inc. (2019), "Comsol Multiphysics user's manual Ver. COMSOL 5.5", USA.
  7. Dixon, D. A., Gray, M. N., and Thomas, A. W. (1985), "A Study of the Compaction Properties of Potential Clay-sand Buffer Mixtures for Use in Nuclear Fuel Waste Disposal", Engineering Geology, Vol.21, pp.247-255. https://doi.org/10.1016/0013-7952(85)90015-8
  8. Incropera, F. P., DeWitt, D. P., Bergman, T. L., and Lavine, A. S. (2006), "Fundamentals of Heat and Mass Transfer, 6th ed", John Wiley & Sons.
  9. Juvankoski, M. (2013), "Buffer design 2012", Posiva 2012-14, Posiva Oy.
  10. Karnland, O. (2010), "Chemical and Mineralogical Characterization of the Bentonite Buffer for the Acceptance Conctrol Procedure in a KBS-3 Repository", Svensk Karn-branslehantering AB Report, SKB TR-10-60.
  11. Kim, M. J., Lee, S. R., Jeon, J. S., and Yoon, S. (2019), "Sensitivity Analysis of Bentonite Buffer Peak Temperature in a High-level Waste Repository", Annals of Nuclear Energy, Vol.123, pp.190-199. https://doi.org/10.1016/j.anucene.2018.09.020
  12. Kim, M. J., Lee, S. R., Yoon, S., Jeon, J. S., and Kim, M. S. (2018), "Effect of Thermal Properties of Bentonite Buffer on Temperature Variation", Journal of the Korean Geotechnical Society, Vol.34, No.1, pp.17-24. https://doi.org/10.7843/kgs.2018.34.1.17
  13. Kjartanson, B., Dixon, D., and Kohle, C. (2005), "Placement of Bentonite Pellets to Fill Repository Sealing System Voids and Gaps", Technical Report No. 06819-REP-01200-10136-R00, Ontario Power Generation.
  14. Lee, C. (2013), "A Benchmark for 2-Dimensional Incompressible and Compressible Mantle Convection Using COMSOL Multiphysics", Journal of the Geological Society of Korea, Vol.49, No.2, pp. 245-265.
  15. Lee, J. O., Brich, K., and Choi, H. J. (2014), "Coupled Hydro Analysis of Unsaturated Buffer and Backfill in a High-level Waste Repository", Annals of Nuclear Energy, Vol.72, pp.63-75. https://doi.org/10.1016/j.anucene.2014.04.027
  16. Lee, J. O., Cho, W. J., and Kwon, S. (2011), "Thermal-hydro-mechanical Properties of Refernece Bentonite Buffer for a Korean HLW Repository", Tunnel and Underground Space, Vol.21, No.4, pp.264-273. https://doi.org/10.7474/TUS.2011.21.4.264
  17. Lee, J. O., Choi, Y. C., and Choi, H. J. (2013), "R&D Status on Gap-filling Materials for the Buffer and Backfill of a HLW Repository", KAERI/AR-1005/2013.
  18. Lee, J. O., Choi, H. J., Kim, G. Y., and Cho, D. K. (2019), "Numerical Analysis of the Effect of Gap-filling Options on the Maximum Peak Temperature of a Buffer in a HLW Repository", Progress in Nuclear Energy, Vol.111, pp.138-149. https://doi.org/10.1016/j.pnucene.2018.11.007
  19. Lee, J. Y., Kim, H. A., Kim, I. Y., Choi, H. J., and Cho, D. G. (2020), "Analyses on Thermal Stability and Structural Integrity of the Improved Disposal Systems for Spent Nuclear Fuels in Korea", Journal of Nuclear Fuel Cycle and Waste Technology, Vol.S, pp. 21-36.
  20. LLoret, A., Villar, M. V., Sanchez, M., Gens, A., Pintado, X., and Alonso, E. E. (2003), "Mechanical behavior of heavily compacted bentonite under high suction changes. Geotechnique, Vol. 53, pp. 27-40. https://doi.org/10.1680/geot.2003.53.1.27
  21. Marjavaara, P. and Holt, E. (2012), "Customized Bentonite Pellets: Manufacturing, Performance and Gap Filling Properties", Working report 2012-62, Posiva Oy, Eurajoki.
  22. Marjavaara, P. and Kivikoski, H. (2011), "Filling the Gap between Buffer and Rock in the Deposition Hole", Woking report 2011-33, Posiva Oy, Eurajoki.
  23. Xiang, G., Ye, W., Xu, Y., and Jalal, F. E. (2020), "Swelling Deformation of Na-bentonite in Solutions Containing Different Cations", Engineering Geology, Vol.277, pp.105757. https://doi.org/10.1016/j.enggeo.2020.105757
  24. Yoon, S. and Kim, G. Y. (2021), "Measuring Thermal Conductivity and Water Suction for Variably Saturated Bentonite", Nuclear Engineering and Technology, Vol.53, pp.1041-1048. https://doi.org/10.1016/j.net.2020.08.017
  25. Zheng, L., Rutqvist, J., Birkholzer, J. T., and Liu, H. H. (2015), "On the Impact of Temperature up to 200℃ in Clay Repositories with Bentonite Engineered Barrier System: A Study with Coupled Thermal, Hydrological, Chemical, and Mechanical Modeling", Engineering Geology, Vol.197, pp.278-295. https://doi.org/10.1016/j.enggeo.2015.08.026