Economical dry storage of large amounts of spent fuel and vitrified high level radioactive waste

The economical dry storage of spent fuel assemblies and vitrified high level radioactive waste demands facilities that fulfil, besides safety requirements, especially the following criteria: minimization of the specific space required for the storage of one fuel assembly or glass cylinder, minimization of the number of active systems and components to alleviate operation and maintenance, application of current materials. Comprehensive thermodynamical calculations on the single and dual cycle dry storage facilities, developed by KWU, have shown that the flow and temperature distributions within the storage rack and the other parts of the facility determine the feasibility of such dry storage systems. The parameters are mainly governed by the orientation and the pitch of the storage racks