A transfer cask system for cooling spent nuclear fuel during the transfer from a spent nuclear fuel pool to a storage or transfer cask is disclosed. A canister containing spent nuclear fuel is inserted into a transfer cask. The transfer cask includes spacing components which define an annular region between the transfer cask and the canister. The transfer cask includes air inlets near a bottom end that permit air to flow through the defined annular region and exit at the open top of the transfer cask, thereby cooling the fuel within the canister. The transfer cask further comprises a neutron shield configured to absorb additional heat and shield radiation that may be generated within the canister. The transfer cask includes a transfer door that can open and close and has support rails that can support a spent nuclear fuel canister located in the transfer cask.

A canister for storing radioactive materials includes a base plate, side wall and a top plate. The top plate includes a top surface with a top edge having a bevel, and with a channel set in from the top edge. The top plate is sealed to the sidewall by a weld formed between the beveled top edge and the top of the side wall. The base plate is sealed to a bottom of the sidewall, so that a sealed vessel is formed.

A canister for storing radioactive materials includes a base plate, side wall and a top plate. The top plate includes a top surface with a top edge having a bevel, and with a channel set in from the top edge. The top plate is sealed to the sidewall by a weld formed between the beveled top edge and the top of the side wall. The base plate is sealed to a bottom of the sidewall, so that a sealed vessel is formed.

A method of handling spent nuclear fuel assemblies immerses the spent nuclear fuel assemblies in water in a relatively short time period when compared to traditional methods. A spent nuclear fuel assembly is removed from a nuclear reactor, an inert gas is applied to the fuel assembly, moisture content in the inert gas is gradually increased as it is applied to the fuel assembly, and the fuel assembly is immersed in water. The fuel assembly is immersed relatively quickly, within about 2 hours or less, which improves safety and allows normal processing and handling equipment to care for the fuel assembly. The fuel assembly may then be loaded into a cask for long-term storage and/or disposal.

A method of handling spent nuclear fuel assemblies immerses the spent nuclear fuel assemblies in water in a relatively short time period when compared to traditional methods. A spent nuclear fuel assembly is removed from a nuclear reactor, an inert gas is applied to the fuel assembly, moisture content in the inert gas is gradually increased as it is applied to the fuel assembly, and the fuel assembly is immersed in water. The fuel assembly is immersed relatively quickly, within about 2 hours or less, which improves safety and allows normal processing and handling equipment to care for the fuel assembly. The fuel assembly may then be loaded into a cask for long-term storage and/or disposal.

To provide a containment cask for storage or transport of radioactive material, without employing a homogenization treatment. Pouring a molten lead between an inner shell 2 and an intermediate shell 3 to serve as a gamma ray shielding material, allowing the lead to cool, and subsequently, filling either one or both of a first void layer 9a formed at a boundary between the inner shell 2 and the poured lead 5a or a second void layer 9b formed at a boundary between the intermediate shell 3 and the poured lead 5a, using a low melting point metal 10 in a closely adhering state. To provide the cask 1 with a good heat-dissipating effect, by filling the void layers 9a, 9b that prevent the cask 1 from dissipating heat, with the low melting point metal 10 that has a superb thermal conductivity.

To provide a containment cask for storage or transport of radioactive material, without employing a homogenization treatment. Pouring a molten lead between an inner shell 2 and an intermediate shell 3 to serve as a gamma ray shielding material, allowing the lead to cool, and subsequently, filling either one or both of a first void layer 9a formed at a boundary between the inner shell 2 and the poured lead 5a or a second void layer 9b formed at a boundary between the intermediate shell 3 and the poured lead 5a, using a low melting point metal 10 in a closely adhering state. To provide the cask 1 with a good heat-dissipating effect, by filling the void layers 9a, 9b that prevent the cask 1 from dissipating heat, with the low melting point metal 10 that has a superb thermal conductivity.

A modular nuclear reactor system includes a lift-out, replaceable nuclear reactor core configured for replacement as a singular unit during a single lift-out event, such as rather than lifting and replacing individual fuel assemblies and/or fuel elements. The system includes a reactor vessel and a power generation system configured to convert thermal energy in a high temperature working fluid received from the reactor vessel into electrical energy. The reactor vessel includes: a vessel inlet and an adjacent vessel outlet arranged near a bottom on the vessel; a vessel receptacle configured to receive a unified core assembly; locating datums in the base of the vessel receptacle and configured to constrain a core assembly in multiple degrees of freedom; and an interstitial zone surrounding the vessel receptacle and housing a set of control or moderating drums.

A container and system for handling damaged nuclear fuel, and a method of making the same. In one embodiment, the invention is a damaged fuel container having a specially designed top cap that can be detachably coupled to the elongated tubular wall by simply translating the top cap into proper position within, the elongated tubular wall, wherein biased locking elements automatically lock the top cap to the elongated tubular wall. In another embodiment, the vent screens of the damaged fuel container are integrally formed rather than being separate components. In still other embodiments, the lower vent screens are arranged on an upstanding portion of the damaged fuel container. In an even further embodiment, the elongated tubular wall is formed by an extrusion process.

A container and system for handling damaged nuclear fuel, and a method of making the same. In one embodiment, the invention is a damaged fuel container having a specially designed top cap that can be detachably coupled to the elongated tubular wall by simply translating the top cap into proper position within, the elongated tubular wall, wherein biased locking elements automatically lock the top cap to the elongated tubular wall. In another embodiment, the vent screens of the damaged fuel container are integrally formed rather than being separate components. In still other embodiments, the lower vent screens are arranged on an upstanding portion of the damaged fuel container. In an even further embodiment, the elongated tubular wall is formed by an extrusion process.