Conceptual study of measures against heat generation for TRU fuel fabrication system

TRU燃料製造システムのための発熱対策の概念設計研究

川口 浩一  ; 滑川 卓志

Kawaguchi, Koichi; Namekawa, Takashi

環境負荷低減を目的にマイナーアクチニド(MA)を炉内で燃焼させるTRU燃料は、含有するMAの崩壊熱により、高い発熱を示す。簡素化ペレット法燃料製造システムにおいては、原料粉末やペレットの酸化,被覆管の酸化等の影響が懸念される。発熱量20W/kgHM程度の燃料を扱う燃料製造システムにおける除熱対策の概念検討を行い、粉末容器,O/M調整炉,燃料要素バンドルについて熱流動解析によって対策の有効性を確認した。

The JAEA has developed advanced FBR cycle system since 1999 as the Feasibility Study (FS). Several combination of fuel and reactor type, reprocessing method and fuel fabrication method were studied. As the result of FS, the combination of oxide fuel, sodium cooling reactor, advanced aqueous reprocessing system and simplified pelletizing fuel fabrication system is chosen as the most promissing fuel cycle system. In the Fast Reactor Cycle technology (FaCT), six development issues for simplified pelletising technology were selected. TRU fuel handling technology, which is heat removal from nuclear fuel material, is one of these issues. Accumulation of decay heat of MA which is contained in TRU fuel cause oxidation of fuel powder, fuel pellet and cladding tube. Authors designed concept of powder hoppper, O/M adjusting furnace and fuel assembling equipment with heat removal function, and evaluated temperature distribution using thermal hydraulics analysis technique. As a result, it is shown that it is possible to cool fuel materials with specific heat generation up to 20 W/kgHM enough, though more detailed study is required for comprehensive equipments.