Research and Development Program on Accelerator Driven Subcritical System in JAEA

Abstract

For a dedicated transmutation system, Japan Atomic Energy Agency (JAEA) has been proceeding with the research and development on an accelerator-driven subcritical system (ADS). The ADS proposed by JAEA is a lead-bismuth eutectic (LBE) cooled fast subcritical core with 800 MWth. JAEA has started a comprehensive research and development (R&D) program since the fiscal year of 2002 to acquire knowledge and elemental technology that are necessary for the validation of engineering feasibility of the ADS. In this paper, the outline and the results in the first three-year stage of the program are reported. Items of R&D were concentrated on three technical areas peculiar to the ADS: (1) a superconducting linear accelerator (SC-LINAC), (2) the LBE as spallation target and core coolant, and (3) a subcritical core design and reactor physics of the ADS. For R&D on the accelerator, a prototype cryomodule was built and its good performance in electric field was examined. For R&D on the LBE, various technical data for material corrosion, thermal-hydraulics and radioactive impurity were obtained by loop tests and reactor irradiation. For R&D on the subcritical core, engineering feasibility for the LBE cooled tank-type ADS was discussed using thermal-hydraulic and structural analysis not only in normal operation but also in transient situations. Reactor physics experiments for subcritical monitoring and physics parameters of the ADS were also performed at critical assemblies.