All Issue

2017 Vol.33, Issue 7 Preview Page
A Prediction of Thermal Conductivity for Compacted Bentonite Buffer in the High-level Radioactive Waste Repository

고준위폐기물 처분시설의 압축 벤토나이트 완충재의 열전도도 추정

Seok Yoon1*
,
Min-Soo Lee2
,
Geon-Young Kim2
,
Seung-Rae Lee3
,
Min-Jun Kim4
윤 석1*
,
이 민수2
,
김 건영2
,
이 승래3
,
김 민준4
1Senior Researcher, Radioactive Waste Disposal Research Division, KAERI
2Principal Researcher, Radioactive Waste Disposal Research Division, KAERI
3Prof., Dept. of Civil and Environmental Eng., KAIST
4Member, Graduate Student, Dept. of Civil and Environmental Eng., KAIST
1한국원자력연구원 방사성폐기물처분연구부 선임연구원
2한국원자력연구원 방사성폐기물처분연구부 책임연구원
3KAIST 건설 및 환경공학과 교수
4KAIST 건설 및 환경공학과 박사과정
*교신저자. *Corresponding Author. 
31 July 2017. pp. 55-64
PDF XML Citation
Abstract

A geological repository has been considered one of the most adequate options for the disposal of high-level radioactive waste. A geological repository will be constructed in a host rock at a depth of 500～1,000 meters below the ground surface. The geological repository system consists of a disposal canister with packed spent fuel, buffer material, backfill material, and intact rock. The buffer is very important to assure the disposal safety of high-level radioactive waste. It can restrain the release of radionuclide and protect the canister from the inflow of groundwater. High temperature in a disposal canister is released into the surrounding buffer material, and thus the thermal transfer behavior of the buffer material is very important to analyze the entire disposal safety. Therefore, this paper presents a thermal conductivity prediction model for the Kyungju compacted bentonite buffer material which is the only bentonite produced in Korea. Thermal conductivity of Kyungju bentonite was measured using a hot wire method according to various water contents and dry densities. With 39 data obtained by the hot wire method, a regression model to predict the thermal conductivity of Kyungju bentonite was suggested.

Keywords
Compacted bentonite buffer
Thermal conductivity
Hot wire method
Regression analysis

심층 처분방식은 고준위폐기물을 처분하기 위한 가장 적합한 대안으로 고려되어지고 있다. 심층 처분시설은 지하 500～1,000m 깊이의 암반층에 설치되며 심층 처분시스템의 구성 요소로는 처분용기, 완충재, 뒷채움 및 근계 암반이 있다. 이 중 완충재는 심층 처분시스템에 있어 매우 중요한 역할을 한다. 완충재는 지하수 유입으로부터 처분용기를 보호하고, 방사성 핵종 유출을 저지한다. 처분용기에서 발생하는 고온의 열량이 완충재로 전파되기에 완충재의 열적 성능은 처분시스템의 안정성 평가에 매우 중요하다고 할 수 있다. 따라서 본 연구에서는 국내 경주산 압축 벤토나이트 완충재에 대한 열전도도 추정 모델을 개발하고자 하였다. 압축 벤토나이트 완충재의 열전도도는 비정상 열선법을 이용하여 다양한 함수비와 건조밀도에 따라 측정하였으며, 총 39개의 실험 데이터를 토대로 회귀분석을 이용하여 경주 압축 벤토나이트의 열전도도 추정 모델을 제시하였다.

References
1
Anthony, J. H. (2007), “Probability and Statistics for Engineers and Scientists”, Third Edition, THOMSON BROOKS/COLE.
2
ASTM C1113/C1113M-09, “Standard Test Method for Thermal Conductivity of Refractories by Hot Wire (Platinum Resistance Thermometer Technique)”, ASTM International.
3
ASTM D5334-14, “Standard Test Method for Determination of Thermal Conductivity of Soil and Soft Rock by Thermal Needle Probe Procedure”, ASTM International.
4
Choi, H. J., Kim, K. S., Cho, W. J., Lee, J. O., and Choi, J. W. (2014), “HLW Long-term Management System Development: Develop-ment of Engineered Barrier System Performance”, Korea Atomic Energy Research Institute Report, KAERI/TR-3859.
5
Cho, W. J., Lee, J. W., and Kwon, S. (2011), “An Empirical Model for the Thermal Conductivity of Compacted Bentonite and a Bentonite-sand Mixture”, Heat and Mass Transfer, Vol.47, pp. 1385-1393.
6
Data solution Consulting Team (2013), “SPSS Statistics Descriptive Satistics and Correlation Analysis”, SPSS Data Solution.
7
Go, G. H., Lee, S. R., Yoon, S., and Kang, H. B. (2014), “Design of Spiral Coil PHC Energy pile Considering Effective Borehole Thermal Resistance and Groundwater Advection Effects”, Appled Energy, Vol.125, pp.165-178. 
8
Hair Jr, J. F., Black, W. C., Babin, B. J., and Anderson, R. E. (2009), Multivariate Data Analysis, 7th Edition, Prentice-Hall.
9
Jeon, K. H., Lee, S. R., and Oh, G. D. (2010), “Probabilistic Analysis of Unsaturated Soil Properties for Korean Weathered Granite Soil”, 24th KKCNN Symposium on Civil Engineering, Hyogo, Japan.
10
Karnland, O. (2010), “Chemical and Mineralogical Characterization of the Bentonite Buffer for the Acceptance Conctrol Procedure in a KBS-3 Repository”, Svensk Kärn-bränslehantering AB Report, SKB TR-10-60.
11
Lee, C. S., Lee, J. W., Choi, H. J., Kim, G, Y., and Kim, K. (2015), “Thermo-hydro-mechanical Modelling of CIEMAT Column Test : Part 1- before Hydration”, Korea Atomic Energy Research Institute Report, KAERI/TR-6216.
12
Lee, I. H. (2014), “Easy Flow Regression Analysis”, Hannarae Publishing Corporation.
13
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.
14
Lee, J. O., Lee, M, S., Choi, H. J., Lee, J. Y., and Kim, I. Y. (2014), “Establishment of the Concept of Buffer for an HLW Repository: An Approach”, Korea Atomic Energy Research Institute Report, KAERI/TR-5824.
15
Lee, J. O., Choi, H. J., and Lee, J. Y. (2016), “Thermal Conductivity of Compacted Bentonite as a Buffer Material for a High-level Radioactive Waste Repository”, Annals of Nuclear Energy, Vol. 94, pp.848-855.
16
Lee, J. Y., Cho, D. K., Choi, H. J., and Choi, J. W. (2007), “Concept of a Korean Reference Disposal System for Spent Fuels”, Journal of Nuclear Science and Technology, Vol.44, No.12, pp.1565-1573. 
17
Lee, M. S., Choi, H. J., Lee, J. O., and Lee, J. P. (2013), “Improve-ment of the Thermal Conductivity of a Compact Bentonite Buffer”, Korea Atomic Energy Research Institute Report, KAERI/TR-5311.
18
Park, H. (2011), “Thermal Conductivities of Unsaturated Korean Weathered Granite Soils”, Master thesis, KAIST.
19
Phoon, K. K., Santoso, A., and Quek, S. T. (2010), “Probabilistic Analysis of Soil-water Characteristic Curves”, ASCE Journal of Geotechnical and Geoenvironmental Engineering, Vol.136, No.3, pp.445-455.
20
Swedish Nuclear Fuel Suppply Co/Division KBS (1983), “Final Storage of Spent Nuclear Fuel-KBS3”, Svensk Kärn-bränslehantering AB Report, Stockholm.
21
Tang, A. M., Cui, Y, J., and Le, T. T. (2008), “A Study on the Thermal Conductivity of Compacted Bentonite”, Applied Clay Science, Vol.41, pp.181-189.
22
Villar, M. V., Martin, P. L., and Barcala, J. M. (2006), “Modification of Physical, Mechanical and Hydraulic Properties of Bentonite by Thermo-hydraulic Gradients”, Engineering Geology, Vol.81, pp. 284-297.
23
Yoo, M., Choi, H. J., Lee, M. S., and Lee, S. Y. (2016), “Measure-ment of Properties of Domestic Bentonite for a Buffer of an HLW Repository”, Journal of the Korean Radioactive Waste Society, Vol.14, No.2, pp.135-147.
24
Yoon, S., Lee, S. R., Kim, Y. T., and Go, G. H. (2015), “Estimation of Saturated Hydraulic Conductivity of Korean Weathered Granite Soils Using a Regression Analysis”, Geomechanics and Engineering, Vol.9, No.1, pp.101-113.
25
Yoon, S., Lee, S. R., Kim, Y. S., Kim, G. Y., and Kim, K. (2016), “Prediction of Ground Thermal Properties from Thermal Response Test”, Journal of the Korean Geotechnical Society, Vol.32, No.7, pp.5-14.
26
Yoon, S., Kim, G. Y., Kim, M. J., and Lee, S. R. (2017), “Evaluation of Water Content Measurement for Bentonite Buffer Material”, Proceeding of KGS Spring National Conference, Seoul, Korea.
Information
  • Publisher :The Korean Geotechnical Society
  • Publisher(Ko) :한국지반공학회
  • Journal Title :Journal of the Korean Geotechnical Society
  • Journal Title(Ko) :한국지반공학회 논문집
  • Volume : 33
  • No :7
  • Pages :55-64
  • Received Date : 2017-05-08
  • Accepted Date : 2017-07-04
  • DOI :https://doi.org/10.7843/kgs.2017.33.7.55
Journal Informaiton Journal of the Korean Geotechnical Society Journal of the Korean Geotechnical Society
Archives
: Vol.23~28 (2007~2012)
  • NRF
  • KOFST
  • KISTI Current Status
  • KISTI Cited-by
  • crosscheck
  • orcid
  • open access
  • ccl
Journal Informaiton Journal Informaiton - close