SEAL STUDIES OF VARIANT BLANKET CONCEPTS AND MATERIALS

Within the European SEAL (Safety and Environmental Assessment of fusio n power, Long-term) program, safety and environmental assessments have been performed which extend the results of the earlier SEAFP (Safety and Environmental Assessment of Fusion Power) program to a wider range of blanket designs and material choices. The four blanket designs ana lysed were those which had been developed within the Blanket program o f the European Fusion Programme. All four are based on martensitic ste el as structural material, and otherwise may be summarized as: water-c ooled lithium-lead; dual-cooled lithium-lead; helium-cooled lithium si licate (BOT geometry); helium-cooled lithium aluminate (or zirconate) (BIT geometry). The results reveal that all the blankets show the favo rable S&E characteristics of fusion, though there are interesting and significant differences between them. The key results are described. A ssessments have also been performed of a wider range of materials than was considered in SEAFP. These were: an alternative vanadium alloy, a n alternative low-activation martensitic steel, titanium-aluminum inte rmetallic, and SiC composite. Assessed impurities were included in the compositions, and these had very important effects upon some of the r esults. Key results impacting upon accident characteristics, recycling , and waste management are described.