Upgrading the experimental database of fission products and actinides release behaviour in the VERCORS program through chemical analysis

VERCORS実験における化学分析結果を用いた核分裂生成物及びアクチニド放出挙動データベースの改良

三輪 周平  ; Ducros, G.*; Hanus, E.*; Bottomley, P. D. W.*; Van Winckel, S.*

Miwa, Shuhei; Ducros, G.*; Hanus, E.*; Bottomley, P. D. W.*; Van Winckel, S.*

核分裂生成物(FP)及びアクチニド放出・移行実験VERCORSにおいて装置配管等への沈着物の化学分析を行うことにより線、線放出核種及び安定核種の破損燃料からの放出挙動を評価した。公衆に対する影響が大きいSrは還元雰囲気において放出が促進されること、Uは水蒸気雰囲気により放出が大きく促進されるが、その多くは燃料近辺に沈着すること等がわかった。また、Rb, Pd, Tc及びPu等の他の核種の放出挙動は従来のVERCORS実験結果からの予想とよく一致した。化学分析結果から放出挙動を評価する手法を用いることにより、線, 線放出核種及び安定核種の放出挙動の雰囲気依存を明らかにし、FP放出挙動データベースの改良に寄与した。

The release behaviour of -ray emitters, -ray emitters and stable nuclide from the degraded fuel in the fission product (FP) and actinide release and transport tests, VERCORS tests, were investigated based on the chemical analysis of their deposits on the components of VERCORS test loops. The release of Sr which has a significant public impact shows the possibility to be enhanced in reducing atmosphere. The release of U was significantly enhanced in steam atmosphere, but almost all the released U remained near the fuel. The release behaviour of other non--ray emitters such as Rb, Pd, Tc and Pu shows the good consistency with the expectation based on the previous VERCORS tests results. The experimental database of the FP and actinide release behaviour was upgraded through the chemical analysis in terms of the effects of atmosphere on the release behaviour of -ray emitters, -ray emitters and stable nuclide.