2    
R&D for Commercialization of Fast Reactor Cycle Technology
FY2010Confirmation of Technical Issues
for Innovative Technology

Determination of Adoptionof Innovative Technology

Fast Reactor Cycle Technology Development(FaCT Project)‫ ع‬Design Study‫ ع‬Experimental Study‫ ع‬International Standardization of‫ ޓ‬Safety Design Requirements‫ ع‬Fundamental R&D

R&D in MONJU‫ ع‬Demonstrating the Reliability of‫ ޓ‬an Operational Power Plant‫ ع‬Establishing Sodium Handling‫ ޓ‬Technology

Domestic Cooperation
International Development of the 4th Generation Reactor

Fast Reactor Cycle Systemthat Achieves Performance Targets ofSafety, Economy, etc., as a Future Energy System

FY2006

Fig.2-1 Overview of research and development efforts targeting commercialization of a fast reactor cycle
R&D activities have been implemented toward the commercialization of fast reactor cycle technology, which has excellent performancein terms of safety, economy, environmental conservation, efficient utilization of resources, and nuclear proliferation resistance. In
FY2011, investigations aiming at international standardization of safety design requirements were in progress to realize top-tier safety
goals for 4th-generation reactor systems.

Various activities, such as the FaCT project and R&D in
the MONJU reactor are being implemented to commercialize
fast reactor cycle technology, as shown in Fig.2-1. Regarding
the FaCT project, innovative technologies to be adopted in
the fast reactor cycle have been determined, and the firstphase of the project has been completed. With respect to theR&D in the MONJU reactor, the system start-up test wasresumed and the core confirmation test was completed. Given
that a review of the nuclear energy policy is underway by thegovernment following the accident at the Tokyo ElectricPower Company, Incorporated Fukushima Daiichi Nuclear
Power Station, the second phase of the FaCT project, which
was scheduled to start in FY2011, was postponed. Currently,international standardization of safety design requirements isunderway in order to realize top-tier safety goals for 4thgeneration reactor systems. The topics introduced in thischapter include subjects regarding further improvement ofsafety. The summary of the topics is as follows.
Electricit de France (EDF) reviewed innovativetechnologies designed to improve safety and reduce the useof materials for the Japan Sodium-cooled Fast Reactor(JSFR) from the perspective of an investor-operator of future
French SFRs, and evaluated that these technologies are also
attractive for future French commercial SFRs (Topic 2-1).
In the JSFR, the goal is to contain the consequences of acore disruptive accident inside the reactor vessel. It wasconfirmed that the introduction of a fuel assembly with an36 JAEA R&D Review 2012

inner duct structure was an effective measure for achieving invessel retention based on fundamental experiments (Topic 2-2).
In addition, bent pipes with a large diameter, which areadopted for a compact component layout, have coolant
flowing through them at high speeds. The flow in the pipe elbow
was evaluated using flow experiments in order to prevent
pipe failure caused by flow induced vibration, and the resultsof this study are reflected in the piping design (Topic 2-3).
Regarding the reduction in the creep strength of modified
9Cr-1Mo steel, which is utilized as the piping material, atelevated temperatures for long periods, a creep lifetime
prediction expression was prepared through analysis of creep
test data corresponding to the failure mechanism, and it wasconfirmed that the piping design of JSFR is assured(Topic 2-4). Even in the case of a station blackout caused bya tsunami, after shutting down the MONJU reactor, it was
successfully shown that the natural circulation of the coolant,
and thus the reactor core cooling, is possible as long as theflow path of the coolant is ensured (Topic 2-5).
With respect to the R&D of fuel fabrication techniques, thefeasibility of a fuel fabrication process based on a simplified
pelletizing method, which enables simplification of the fuelfabrication process, was experimentally confirmed after
testing the tumbling granulation and die lubricating-typepelletizing methods as well as the ability to adjust the oxygen
to metal ratio for sintering (Topic 2-6).