Description of initial reference design and identification of safety aspects

A reference design of the fluid fuel circuit and the emergency draining system has to be defined and optimized in the frame of the SAMOFAR project, together with the interaction phenomena between the reactor and the chemical plant. The present deliverable is divided in two main parts dedicated to the fuel salt circuit and the draining system. Each part comprises three sections: - a first section named ‘Feedback from EVOL and previous studies: list of identified constraints’ explains the constraints leading to some design options on the basis of past studies (typically from the EVOL project and some previous MSFR parametric studies); - a second section named ‘Proposition of initial reference design’ proposes a preliminary design, based on the constraints identified, to be used as a basis for the optimization studies foreseen in the SAMOFAR project. This design is not fixed: it will be optimized and will evolve all along the project as will this deliverable itself; - a third section named ‘Developments and studies in the frame of SAMOFAR’ in which all the partners involved in the WP1 will list the studies that are undertaken during the project. Deliverable 1.1 presents the initial reference design and operation procedures of the MSFR proposed by CNRS and the other partners of WP1 at the beginning of the project. The fuel circuit is enclosed in an internal vessel which serves as the container for the fuel salt, with 16 cooling sectors arranged circumferentially in the vessel, inserted from the top. This design results from previous physical and safety preliminary studies and aims at minimizing the fuel leakage occurrences and optimizing the use of the liquid salt both as fuel and coolant. The proposed design for the emergency draining system is based on the same idea, with a vessel containing the drained fuel salt with cooling rods to control the salt temperature on the short to long term. Such rods contain an inert salt used for its thermal inertia. The draining tank geometry has been defined in order to ensure a subcritical configuration in any situation. During the project, this description will be continuously updated by including all improvements and recommendations from the other work packages. This deliverable will thus be a living document, to follow this evolution all along the project.