Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT) (방사성폐기물학회지)

Korean Radioactive Waste Society (한국방사성폐기물학회)
권호 표지
DOI QR코드

DOI QR Code

Criticality Uncertainty Analysis of Spent Fuel Transport Cask applying Burnup Credit

연소도이득효과(BUC) 적용 사용후핵연료 운반용기의 임계 불확실도 평가

  • Received : 2011.02.16
  • Accepted : 2011.08.29
  • Published : 2011.09.30
Download PDF
⟨ Previous Next ⟩

Abstract

In general, conventional criticality analyses for spent fuel transport/dry storage systems have been performed based on assumption of fresh fuel concerning the potential uncertainties from number density calculation of Transuranic and Fission Products in spent fuel. However, because of economic loss due to the excessive criticality margin, recently the design of transport/dry storage systems with Burnup Credit(BUC) application has been actively developed. The uncertainties in criticality analyses on transport/storage systems with BUC technique show strong dependance upon initial enrichment and burnup rate, whereas those in the conventional criticality evaluation based on fresh fuel assumption do not show such a dependance. In this study, regulatory-required uncertainties of the criticality analyses for BK 26 Cask, which is conceptually designed spent fuel transport cask with BUC corresponding to the limiting circumstances on nuclear power plants in Korea, are evaluated as a function of initial enrichment and burnup rate. Results of this study will be used as basic data for spent fuel loading curve of BK 26 Cask.

국내 외 수많은 수송 건식저장 시스템의 임계해석은 사용후핵연료내에 초우라늄물질(transuranic) 및 핵분열생성물(fission products) 계산의 불확실성을 이유로, 신연료로 가정된 가상연료를 적용하여 평가해왔다. 그러나 과도한 임계 여유도에 따른 경제적 손실이 크기 때문에 최근 들어 연소도이득(Burnup Credit, BUC)이 반영된 수송 건식저장 시스템의 설계 및 상용화가 추진되고 있다. 이러한 BUC 기술은 기존 임계해석 시요구되는 상수화된 불확실도와 달리 초기 농축도와 연소도 구간에 따라 상이한 불확실도를 갖게 된다. 이에 본 연구에서는 '국내 원전의 제한사항이 반영된 26다발 SNF 장전 BUC 적용 용기'(이하 BK 26 Cask)를 대상으로 관련 기술표준 및 설계요건에서 요구되는 불확실도를 평가하여 농축도 및 연소도의 함수로 계산하였다. 본 연구결과는 추후 BK 26 Cask 국내 사용후핵연료의 장전 수용률 분석의 기반자료로 활용된다.

Keywords

References

  1. International Standard, ISO/DIS 27468, "Nuclear criticality safety - Burnup credit in evaluations of systems containing PWR fuels", 2009.
  2. Deutsches Institut fur Normung, DIN 25471, "Kritikalitatssicherheit unter Anrechnung des Brennelementabbrands bei der Lagerung und Handhabung von Brennelementen in Brennelementlagerbecken von Kernkraftwerken mit Leichtwasserreaktoren", 2009.
  3. Interim Staff Guidance, ISG-8 Revision.2, "Burnup Credit in the Criticality Safety Analyses of PWR Spent Fuel in Transport and Storage Casks", 2002.
  4. ANSI/ANS-8.27-2008, "Burnup Credit for LWR Fuel"
  5. 한국수력원자력(주), "경수로 사용후핵연료 건식저장 시설 최적 설계기술 개발", 2009.
  6. S. M. Bowman, W. C. Jordan, J. F. Mincey, C. V. Parks, "Experience with the SCALE Criticality Safety Cross-Section Libraries," Oak Ridge National Laboratory, 2000.
  7. J. C. Dean, R. W. Tayloe, Jr, "Guide for Validation of Nuclear Criticality Safety Calculational Methodology", NUREG/CR-6698, 2001.
  8. J. J. Lichtenwalter, S. M. Bowman, M. D. DeHart, and C. M. Hopper, "Criticali ty Benchmark Guide for Light-Water-Reactor Fuel in Transportation and Storage Packages", NUREG/CR-6361, 1997.
  9. Nuclear Energy Agency, OECD, "International Handbook of Evaluated Criticality Safety Benchmark Experiments" NEA/NSC/DOC(95)03, Volume VI, 2008.
  10. M. Rahimi, E. Fuentes, and D. Lancas ter, "Isotopic and Criticality Validation for PWR Actinide-Only Burnup Credit," DOE/RW-0497, 1997.
  11. 이성희, 한영태, 안준기, "사용후핵연료 저장시설의 임계해석 시 연소도 고려 영향 분석", Proceedings of the Korean Radioactive Waste Society Conference, pp. 261-262 (2005).
  12. I. C. Gauld, "Strategies for Application of Isotopic Uncertainties in Burnup Credit", NUREG/CR-6811, 2003.
  13. R.J. Cacciapouti, S.Van Volkinburg, "Axi al Burnup Profile Database for Pres surized Water Reactors", YAEC-1937, Yankee Atomic Electric Company, 1997
  14. J.C. Wagner, M. D. DeHart, C.V. Parks, "Recommendations for Addressing Axial Burnup in PWR Burnup Credit Analy ses", NUREG/CR-6801, 2003
  15. 박덕진, 한영태, 이성희, "연소도고려 임계해석을 적용한 사용후핵연료 운반용기 수용성 결정요소 분석", Proceedings of the Korean Radioactive Waste Society Conference, pp. 449-450(2008).
  16. 한국수력원자력(주), "울진원자력 1,2호기 최종안전성 분석보고서", 2003