A system for externally cooling a cask containing heat-emitting spent nuclear fuel includes the cask comprising a radiation shielding body defining an internal cavity configured to hold a canister containing the spent nuclear fuel. A continuously annular cooling jacket extends circumferentially around an external surface of the cask body. The cooling jacket may have a double shell construction including an internal cavity for a cooling medium which provides an external heat sink for absorbing heat radiated from the external wall surface of the cask 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 cask. In one embodiment, the cooling medium may be dry ice which undergoes sublimation by absorbing the heat to change from solid to gaseous phase directly. The jacket may be formed of multiple segments.

A system for externally cooling a cask containing heat-emitting spent nuclear fuel includes the cask comprising a radiation shielding body defining an internal cavity configured to hold a canister containing the spent nuclear fuel. A continuously annular cooling jacket extends circumferentially around an external surface of the cask body. The cooling jacket may have a double shell construction including an internal cavity for a cooling medium which provides an external heat sink for absorbing heat radiated from the external wall surface of the cask 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 cask. In one embodiment, the cooling medium may be dry ice which undergoes sublimation by absorbing the heat to change from solid to gaseous phase directly. The jacket may be formed of multiple segments.

An apparatus for supporting radioactive fuel assemblies, such as spent nuclear fuel. In one aspect, the apparatus is in the form of a fuel rack having adjustable height pedestals. In another aspect, the apparatus is a canister including a first pressure vessel forming a first cavity and a second pressure vessel forming a second cavity, the first pressure vessel located in the second cavity of the second pressure vessel. An inner surface of the second pressure vessel may be in continuous surface contact with an outer surface of the first pressure vessel to form a dual-walled canister.

Casks shield materials and passively remove heat via heat transport paths from deep inside to outside the cask. The transport path may be heat pipes and conductive rods that are non-linear so that radiation is always shielded by the cask. A damper may surround an end of the heat transport path to control heat loss from the cask. A jacket of fluid or meltable material that conducts heat by convection may surround stored materials ensure an even temperature within the cask, and the heat transport path may absorb heat from the jacket. Casks are useable to safely store, transport, and dispose of any sensitive or heat-generating material. Casks may be opened or closed to simultaneously load and offload materials at a consistent operating temperature provided by heaters in the cask.

Casks shield materials and passively remove heat via heat transport paths from deep inside to outside the cask. The transport path may be heat pipes and conductive rods that are non-linear so that radiation is always shielded by the cask. A damper may surround an end of the heat transport path to control heat loss from the cask. A jacket of fluid or meltable material that conducts heat by convection may surround stored materials ensure an even temperature within the cask, and the heat transport path may absorb heat from the jacket. Casks are useable to safely store, transport, and dispose of any sensitive or heat-generating material. Casks may be opened or closed to simultaneously load and offload materials at a consistent operating temperature provided by heaters in the cask.

A radioactive nuclear waste storage system includes a cask comprising a hermetically sealed internal cavity configured for holding the waste such as spent nuclear fuel submerged in an inventory of water. One or more pressure surge capacitors disposed inside the cask include a vacuum cavity evacuated to sub-atmospheric conditions prior to storage of fuel in the cask. At least one rupture disk seals a vacuum chamber inside each capacitor. Each rupture disk is designed and constructed to burst at a predetermined burst pressure level occurring inside the cask external to the capacitor. This allows excess cask pressure occurring during a high pressure excursion resulting from abnormal operating conditions to bleed into capacitor, thereby returning the pressure inside the cask to acceptable levels. In one embodiment, the capacitors are located in peripheral regions of the cask cavity adjacent to the circumferential wall of the cask body.

A radiation and impact-protected radioactive waste cask, comprising a container for radioactive waste including an outer steel wall, an inner steel wall, a layer of lead located between the two steel walls, a steel base, a steel cover, a volume of quartz sand located inside the container, at least one internal vessel that is surrounded at least partially by the volume of quartz sand; and radioactive waste located inside the receptacle, wherein the radiation and impact-protected radioactive waste cask further comprises a removable outer transportation canister, wherein the removable outer transportation canister comprises a hollow cylindrical or polygonal body with a lower end and an upper end, configured for fittingly receiving therein the container for radioactive waste, wherein the lower end is closed by a fixed bottom and the upper is closed with a removable canister cover, wherein the hollow cylindrical or polygonal body, the fixed bottom and the removable canister cover are made of at least three layers, an outer layer made of armor grade steel, an inner layer made of high strength steel, and an intermediate layer between said outer and inner layers, said intermediate layer being made of one or more strati comprising ceramic material, wherein said ceramic material is selected from oxide ceramics, non-oxide ceramics and mixtures thereof.

A package for transporting and/or storing radioactive materials, comprises a cavity for housing radioactive materials, as well as a radiological protection device comprising radiological protection elements arranged in an annular space, at least two successive radiological protection elements along a given direction of the annular space, from a longitudinal direction and a circumferential direction, and a locking member designed to limit and/or prevent the distancing of the two radiological protection elements relative to one another in a given direction.

A modular dry spent fuel canister system in which several different types of inner spent nuclear fuel canisters can be loaded into the same outer cask family. This family typically includes a storage overpack, a transfer cask, a transportation cask and support or auxiliary hardware. The various canisters can be loaded interchangeably into the different types of outer casks. The inner canisters are differentiated not by physical fuel type or dimension, but by the engineering objective or criterion that applies to the spent fuel being stored. One such objective may be for a single canister to store a large number of assemblies economically and safely. A second is a canister designed to greatly reduce the cooling time (or radioactive decay time) that must pass in order to load spent nuclear fuel for off-site storage, so as to meet the decay heat requirements and capabilities of the off-site storage system.

A storage apparatus with radiation shielding for spent nuclear fuel includes a fuel basket comprising elongated fuel storage tubes each defining an open cell configured to hold a nuclear fuel assembly. Gamma radiation attenuation inserts are nested inside at least some of the storage tubes. The inserts each comprise elongated open-ended tubular bodies which may have a rectangular cuboid configuration with square cross section. The inserts are composed of a dense metallic material selected for blocking gamma radiation and may have high thermal conductivity for effective heat dissipation from the decaying nuclear fuel. Attenuation inserts can occupy some or all perimeter tubes to provide shielding against gamma radiation emanating in a lateral direction from the fuel basket. The inserts may include upper and lower securement features for detachable fixation to the storage tubes, and air/gas flow cutouts.