Investigation methods and handling of hazardous materials for fusion blanket applications

The helium cooled pebble bed blanket (HCPB) is based on the use of ceramic breeder and beryllium pebble beds. The investigation into thermal–mechanical behaviour of such pebble beds is a key point in the design of this solid breeder blanket. For several years the firm Goraieb Versuchstechnik (GVT) has been working in this field in collaboration with Forschungszentrum Karlsruhe. In particular, heat transfer coefficients in pebble beds, bed-filling methods in ITER breeding blanket geometry, mechanical compression tests of beryllium pebble beds at high temperatures and mechanical pressures up to 8 MPa and measurements of the pressure drop of purge gas (helium) flowing through the bed were performed. In the last 2 years GVT also started an activity related to the production of FLiBe for fusion application and, as beryllium dusts and fumes are hazardous materials special safety equipment have been developed. The experiments were done in glove boxes with controlled atmosphere to avoid any contamination. The paper deals with the description of the adopted procedures and techniques developed for the different experiments