Studies of super-critical CO gas turbine power generation fast reactor(Contract research, Translated document)

Kisohara, Naoyuki ; Kotake, Shoji; Sakamoto, Yoshihiko 

(1) Preliminary design of an SFR that adopts a super-critical CO turbine has been made. This SFR system eliminates secondary sodium circuits. The power generation efficiency of the SFR is 42%. Compared to a SFR that adopts a steam cycle with secondary sodium circuits, the reactor building volume of the SC-CO SFR is reduced by 20%. (2) A super-critical CO cycle test loop was fabricated. The high efficiency of a compressor is confirmed near the super-critical region. The temperature efficiencies of PCHE recuperators are 98-99% (hot leg). No flow instability is observed in the loop operation. (3) Na/CO Reaction tests were executed. Continuous reaction occurs more than 570-580C. Reaction products are NaCO and CO. The reaction heat is 50-75kJ/Na-mol. (4) Safety calculation was done for 1 DEG tube failure in Na/CO heat exchanger. The maximum pressure in the primary circuit is below the allowed level. The void reactivity of the reactor core also has no affect. The reaction product brought no sodium flow blockage in fuel assemblies. (5) After an exposure of 600C-5000 hours in super-critical CO environment, the corrosion of 12Cr steel and 316FR were 170g/m and 5g/m, respectively. 316 FR shows a good corrosion proof property.