Preliminary Estimation of Activation Products Inventory in Reactor Components for Kori unit 1 decommissioning

고리1호기 해체시의 원자로 구조물에서의 방사회 생성물 재고량 예비평가

  • Lee, Kyung-Jin (KOREA Hydro & Nuclear Power Co., Ltd (KHNP) Nuclear Environment Technology Institute (NETEC)) ;
  • Kim, Hak-Soo (KOREA Hydro & Nuclear Power Co., Ltd (KHNP) Nuclear Environment Technology Institute (NETEC)) ;
  • Sin, Sang-Woon (KOREA Hydro & Nuclear Power Co., Ltd (KHNP) Nuclear Environment Technology Institute (NETEC)) ;
  • Song, Myung-Jae (KOREA Hydro & Nuclear Power Co., Ltd (KHNP) Nuclear Environment Technology Institute (NETEC)) ;
  • Lee, Youn-Keun (Korea institute of Nuclear Safety (KINS))
  • 이경진 (한국수력원자력(주) 원자력환경기술원) ;
  • 김학수 (한국수력원자력(주) 원자력환경기술원) ;
  • 신상운 (한국수력원자력(주) 원자력환경기술원) ;
  • 송명재 (한국수력원자력(주) 원자력환경기술원) ;
  • 이윤근 (한국원자력안전기술원)
  • Published : 2003.06.30

Abstract

Based on the necessity to evaluate the activation products inventory during decommissioning lot domestic nuclear power plants, a preliminary estimation of the activation products inventory for Kori unit 1, which is getting close to the end of lifetime, was carried out with ANISN and ORIGEN2 code. In order to calculate neutron nux using ANISN code, the reactor was divided into 9 zones from core to bioshield concrete for radial direction. Also :he cross-section of main nuclides were calibrated with neutron flux in the reactor pressure vessel(RPV) region. The results showed that 95 % of tile total radioactivity in RPV from reactor shutdown to 10 years came from the nuclides of $^{55}Fe,\;^{59}Ni,\;^{63}Ni\;and\;^{60}Co$. And the total radioactivity with cooling of more than 50 years after decommissioning was no more than 0.2 % of at the time of shutdown. Considering the weight of RPV is 210 tons, the total radioactivity of RPV reached to $5.25{\times}10^{6}GBq$ at shutdown time. As compared with the total radioactivity of bioshield concrete at reactor shutdown time, the radioactivity after tooling more than 10 years was below 1 %.

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