Tritium control in helium-cooled blankets

Abstract

As a part of the Blanket Comparison and Selection Study (BCSS), GA Technologies was responsible for the design of helium-cooled, solid- and liquid-metal breeder blankets. Conceptual blanket designs were developed, including the consideration of the generation, transport, and extraction of tritium. Evaluations were made of the inventory and leakage of tritium for helium-cooled Li/sub 2/O and LiAlO/sub 2/ and liquid lithium breeder blankets for tokamak and tandem mirror reactors. To facilitate the evaluation, a solid breeder tritium code TRIT4 was developed. The results from this study indicate that tritium inventories and leakages are acceptable for the proposed helium-cooled blankets. An assumption made in the tritium leakage calculations was that tritium is released to the helium purge and coolant streams as T/sub 2/ and remains in that form. If oxidation to T/sub 2/O is possible, significant reduction in the tritium leakage will be possible. We conclude that more experimental data on breeder material properties and tritium permeation behavior are needed. However, we are certain that an adequate number of different techniques are available to control the breeder tritium inventory and leakage to an acceptable level in helium-cooled solid- and lithium-breeder blankets.