Comparison of advanced fast reactor pool and loop configurations from the viewpoint of construction cost

Comparative evaluation of fast reactor pool/loop configurations in the JAEA feasibility study (FS) from 1996 to 2006 has been re-evaluated from the new point of view. In the FS, both pool and loop configurations have been investigated. The FS loop concept (FS-loop) is an advanced two-loop design which is being developed in the Fast Reactor Cycle Technology Development (FaCT) project as Japan Sodium-cooled Fast Reactor (JSFR). In this study, a brief description of the FS pool concept (FSpool) has been provided. The FS-pool pursues a compact reactor vessel structure using a flask shape intermediate heat exchanger. The original FS pool/loop comparison in 2000 concluded that material amounts of those systems were about similar between pool and loop configurations. However, the present comparison based on the reactor vessel structure and primary cooling system pointed out relatively good economic potential of the FS-loop concept, because differences in the secondary cooling systems of the pool/loop configurations are not essential from the viewpoint of pool/loop comparison. In addition, a rough estimation method of a reactor vessel diameter against power has been proposed and the result has been compared with RV diameters of various pool/loop concepts. The discussion on the reactor vessel diameter shows that the FS-pool reactor vessel is the most compact of the recent commercial reactor designs such as SPX-2, SNR-2, EFR, CDFR and BN-1600. This study points out better economic potential of FS-loop (present JSFR) as a result of competition with the most compact pool concept.

Research highlights▶ Comparison of pool and loop sodium-cooled reactors in the same design stage has been conducted. ▶ The advanced loop type successfully simplifies the plant system adopting advanced technologies. ▶ Mass amount of the advanced loop type is less than that of the most compact pool types.