Passive cooling device for casks containing nuclear fuel

A system for externally cooling a container containing heat-emitting spent nuclear fuel includes a container comprising a radiation shielding body defining an internal cavity configured to contain a vessel containing the spent nuclear fuel. A continuous annular cooling jacket extends circumferentially around an external surface of the container body. The cooling jacket may have a double-shell construction including an internal cavity for a cooling medium that provides an external heat sink for absorbing heat radiated from the outer wall surface of the container generated by the spent nuclear fuel. The heat emitted by the spent nuclear fuel is absorbed by the cooling medium in the cooling jacket, thereby in turn cooling the container. In one embodiment, the cooling medium may be dry ice that undergoes sublimation by absorbing heat to change from solid to gas phase directly. The jacket may be formed by multiple segments. (Automatic translation with Google Translate, no legal value)