Super safe small reactor RAPID-L conceptual design and R&D, JAERI's nuclear research promotion program, H11-002 (Contract research)

Kobe, Mitsuru*; Tsunoda, Hirokazu*; Mishima, Kaichiro*; Kawasaki, Akira*; Iwamura, Takamichi

JAERI-Tech 2003-016, 68 Pages, 2003/03

JAERI-Tech-2003-016.pdf:4.37MB

The 200 kWe uranium nitride fueled lithium cooled fast reactor "RAPID-L" combined with thermoelectric power conversion system that can be operated unmanned without refueling for up to ten years has been demonstrated. The RAPID refueling concept enables quick and simplified refueling, and achieves plant design lifetime over 20 years. A significant advantage of the RAPID-L design, which does not require the use of control rods - is the introduction of the innovative reactivity control systems: lithium expansion module (LEM), lithium injection module (LIM) and lithium release module (LRM). LEM is the most promisiong candidate for improving inherent reactivity feedback. LEMs could realize burnup compensation. LIMs assure sufficient negative reactivity feedback in unprotected transients. LRMs enable an automated reactor startup by detecting the hot standby temperature of the primary coolant. All these systems use Li as liquid poison and are actuated by highly reliable physical properties (volume expansion of Li for LEM, and freeze seal melting for LIM and LRM).