The European Lead-cooled EFIT Plant: an industrial-scale Accelerator-Driven System for Minor Actinide Transmutation

In order to reduce the volume and the radiotoxicity of the nuclear waste coming from the operation of existing PWRs, accelerator-driven systems (ADS) have been envisioned. The European Facility for Industrial-Scale Transmutation (EFIT) plant is the first ADS design that has been going into a rather detailed engineering level. EFIT a lead-cooled, 385-MW (thermal) ADS prototype for minor actinide (MA) transmutation designed to achieve an optimal MA destruction rate of 42 kg/TW.h. The spallation target unit is located in the center of the diagrid where 800-MeV protons from the accelerator impinge on a free surface of lead exposed to vacuum. The core inlet temperature was set at 400°C (sufficiently large safety margin to lead freezing) and the core outlet temperature was limited to 480°C (acceptable corrosion). The primary circuit is designed for effective natural circulation and the design offers good protection in case of a blackout accident. Three systems contribute to the decay heat removal : steam generators, direct reactor cooling and isolation condenser. The EFIT plant exhibits four primary pumps; eight steam generator units, provide heat removal under normal operation. An estimate of the EFIT plant cost has been performed with a best estimate of about €1890 million.