Mains Challenges and Achievements for the Decommissioning of Creys-Malville - 13074

A significant experience is currently being developed for the decommissioning of Creys-Malville Nuclear Power Plant, a Fast Breeder Reactor with a capacity of 1200 MWe. As in any decommissioning project, dismantling of the large components and of the Reactor Vessel Internals are issues at Creys-Malville NPP. But for a FBR those issues are more challenging because sodium induced risks have to be mitigated before any dismantling activities. A significant experience is currently being developed for the dismantling of Creys-Malville. Existing processes, such as carbonation, have been successfully applied to the treatment of large components and have facilitated their later segmentation. New techniques and approaches, such as the introduction of siphons into the vessel or the development of the laser cutting process, have also been developed and successfully implemented. Nevertheless, some challenges lie ahead of the project: the efficiency of the application of carbonation to the treatment of residual sodium in the reactor vessel has still to be demonstrated and the underwater dismantling of the reactor vessel internals will be a premiere for a FBR. All those processes or techniques are complex and require a tremendous effort for their design, testing and implementation. Therefore, the experience feedback collected on Creys-Malville decommissioning project is shared with the CEA project team that is working on the conceptual design of ASTRID, a prototype for a new generation of FBR. The objective of this cooperation is the improvement of the design of the new generation in order to avoid the complex activities that were required for the decommissioning of SPX.