In Situ Tritium Separation and Hydrogen Isotope Pumping for Liquid Metal Divertor Applications

A liquid metal centrifuge is being developed for the extraction of deuterium and tritium from lithium inventory in a closed-loop liquid metal system. Dilute solutions of lithium tritide (LiT) and lithium deuteride (LiD) will form when the temperature of the mixture of deuterium and tritium in lithium is reduced. The large density differences of LiD and LiT compared to pure liquid lithium will then be utilized for the separation into an enriched slurry, which can be later broken down through electron beam heating. [1] The magnetic centrifuge system is being designed based on an electromagnetic liquid metal (EMLM) pumping method. The magnetohydrodynamic (MHD) effects of Lorentz forces are implemented for liquid metal circulation, with externally applied magnetic fields and current driving the flow. A centrifuge system is constructed and optimized at Princeton Plasma Physics Laboratory, first tested with galinstan (67% Gallium, 20.5% Indium, and 12.5% Tin) separating crystal impurities. Simulations are performed to characterize performance of the galinstan centrifuge, and compared to experimental results. The next iteration will be a system for liquid lithium, running experiments at University of Illinois Urbana-Champaign for lithium hydride (LiH) separation using the density differences between Li and LiH.

[1] E. Kolemen, and R. Majeski. A method to distill hydrogen isotopes from lithium. Patent M-924. Princeton Plasma Physics Laboratory, https://www.pppl.gov/m-924.