Deuterium ion irradiation for tritium breeding material and evaluation for tritium inventories in test blanket module and blanket of a demonstration reactor

Abstract

The tritium produced in a tritium breeder of blanket has to be recovered under the temperature distribution to reduce the tritium inventory. Lithium titanate pebbles were irradiated by deuterium ions with different temperatures and ion fluences. The deuterium retained in the pebbles desorbed in forms of HD, D 2 , HDO and D 2 O. The amount of retained deuterium decreased for the temperature higher than 473 K, and became to zero for the temperature higher than 773 K. If the temperature range is taken from 573 to 1173 K in the solid breeder TBM, the tritium inventory is lower than 1 gram. However, in the demonstration reactor, the total tritium inventory of blankets becomes a few kilograms. For the reduction of the tritium inventory, the region with the low temperature region has to be significantly reduced.2 Keywords test blanket module (TBM), blanket, tritium inventory, lithium titanate, deuterium ion irradiation,

D-depth profiling in as-implanted and annealed Li-based breeder blanket ceramics

“…the European HCPB concept) the operational temperature will be limited to 900 °C [15], the presented results indicate that Li-based ceramics are very promising candidates for breeder applications. However further investigations of light species behaviour in damaged (e~, n or y irradiated) ceramics might be carried out in order to achieve more accurate conclusions.…”

“…Next the samples were Room temperature implanted with a 100 keV D 2 ion-source. Since the operational temperature of a solid breeding material has been estimated to be in the range from 300 °C to 900 °C [15], the D desorption profiles were then studied as a function of temperature by Resonance Nuclear Reaction Analysis (RNRA), using the D ( 3 He, p) 4 He nuclear reaction up to the total D outgas. Considering fusion interests towards the search of solid breeders with the highest possible lithium contents, the D thermal diffusion is then discussed comparatively in terms of the materials composition, microstructure and release temperature.…”

3He Behaviour in Li2TiO3 Ceramics for Fusion Breeding Blanket Applications

“…Focusing on Fusion applications, the most relevant result emerging from this work is the fact that the total release of 3 He gas occurs in the estimated BB temperature range (300 ºC ÷ 900 ºC) [10]. Assuming that the 3 He diffusion behavior is applicable to the eventual nuclear reaction products T and 4 He, following the hypothesis which opens this paper, then a pebble bed made of MTi ceramic could then be considered a good candidate for a fusion BB, not only for its good mechanical properties under irradiation [11], and great potentiality for recycling and reprocessing [12 ], but also due to the easy mobility of the light gases though its porous structure at fusion operational temperature condition.…”

Effects of hydrogen mixture into helium gas on deuterium removal from lithium titanate

“…1) and irradiated with deuterium ions at RT. The energy of deuterium ion was 1.7 keV and the ion fluence was 3.0 × 10 18 D/cm 2 , at which the amount of retained deuterium in the pebbles was saturated [10,11]. The implantation depth of the D ion was estimated to be approximately 45 nm calculated by SRIM code [12].…”