TRITIUM REMOVAL FROM VARIOUS LITHIUM ALUMINATES IRRADIATED BY FAST AND THERMAL-NEUTRONS (COMPLIMENT EXPERIMENT)

Within the frame of the COMPLIMENT experiment, gamma-LiAlO2 specimens with different microstructures (grain size distributions) were tested in the same environmental conditions to compare the effects caused by Li-6(n, alpha)T reaction and by fast neutron scattering, the damaging dose being held at about the same level (1.6-1.8 dpa). The tritium ret ention times were obtained by the tritium removal of isothermal anneal ing under He+0.1% H-2 sweeping gas. In spite of the different Li bumup s (2.5% and 0.25%) and the residual tritium concentrations which were found in the irradiated specimens (4.3 Ci/g and 0.09 Ci/g, respectivel y, for specimens held at 450-degrees-C during the irradiations), the k inetics of tritium removal was not found to be discriminated by the tw o different irradiations. Moreover, the results were found to agree wi th those previously obtained by the ''in-situ'' TEQUILA experiment, pe rformed on the same type of Li ceramics. Hence, the apparent first ord er desorption mechanism has been confirmed to control the kinetics of tritium removal from the porous fine grain gamma-LiAlO2 ceramics.