29th Symposium on Fusion Technology (SOFT 2016)

P3.151 Design and fabrication of a Permeator Against Vacuum prototype for testing at Lead-Lithium facility

7 Sep 2016, 11:00

1h 20m

Foyer 2A (2nd floor), 3A (3rd floor) (Prague Congress Centre)

Board: 151

Poster H. Fuel Cycle and Breeding Blankets P3 Poster session

Speaker

Belit Garcinuno (Fusion Technology Division)

Description

Tritium recovery is one of the major issues of a future DEMO reactor, in order to accomplish with the requirement of tritium self-sufficiency. Different techniques have been proposed over the years for the extraction of tritium, depending on the Breeding Blanket technology. After a preliminary selection, the EUROfusion Programme has considered the Permeation Against Vacuum (PAV) technique as baseline for those blankets which use PbLi as breeder. In this framework, an experimental PbLi loop is under construction at CIEMAT with the main objective of testing the PAV technique operating at conditions relevant for the actual European DCLL breeding blanket (i.e. high PbLi velocity, maximum temperature of 550 ºC, low tritium concentration).A conceptual design of a squared multi-channel PAV for its implementation in the loop has been produced. Its geometrical and physical characteristics have been obtained through a detailed analysis of the efficiency, defined as the difference between tritium concentrations at the entrance and exit of the extraction unit. With regard to the PAV membrane, previous studies have shown the feasibility of using tantalum or niobium due to their good permeability and compatibility with PbLi. However, in order to save costs and time a preliminary α-Fe membrane has been considered for the prototype, in spite of its low permeability. Notwithstanding this first device is considered a low-efficiency prototype it is able to demonstrate the feasibility of the technique.Structural calculations are also presented and evaluated for the development of the best implementation of the manufacturing process, paying special attention to the interface between the membranes and the main structure in order to avoid PbLi leakages. Other important aspects, such the preservation of an adequate vacuum level and its arrangement system, have been also considered.