A nuclear fuel storage system includes an outer canister and fuel basket positioned therein. The basket is formed by orthogonally arranged and interlocked slotted plates which collectively define exterior side surfaces of the basket and a grid array of open cells each configured to hold a fuel assembly. At least some slotted plates comprise cantilevered plate extensions protruding laterally beyond the side surfaces of the basket to define various shaped peripheral gaps between the basket and canister. The plate extensions are configured to engage the shell of the canister. Vertically elongated reinforcement members are inserted in the peripheral gaps and fixedly coupled to the basket. Reinforcement members may comprise elongated reinforcement plates and/or tubular shimming members which may be fixedly coupled to the slotted plate extensions. The reinforcement members structurally strengthen the fuel basket. The plate extensions further act as fins to enhance heat dissipation from the basket.

Methods and systems for stabilizing spent fuel assemblies from sodium-cooled nuclear reactors using Zamak are described herein. It has been determined that there is a synergism between Zamak and sodium that allows Zamak to form thermally-conductive interface with the sodium-wetted surfaces of the fuel assemblies. In the method, one or more spent fuel assemblies are removed from the sodium coolant pool and placed in a protective sheath. The remaining volume of the sheath is then filled with liquid Zamak. To a certain extent Zamak will dissolve and alloy with sodium remaining on the fuel assemblies. Excess sodium that remains undissolved is displaced from the sheath by the Zamak fill. The Zamak is then cooled until solid and the sheath sealed. The resulting Zamak-stabilized spent fuel assembly is calculated to have sufficient internal thermal conductivity to allow it to be stored and transported without the need for liquid cooling.

The present application relates to an unloading and temporary storage device. The unloading and temporary storage device includes a stock bin, a stock bin external member, a stock bin internal member, a shielding module and a loading module; the stock bin includes a barrel and a tank body; the stock bin external member includes a cooling water jacket; the stock bin internal member includes a straight bin, an inclined bin and an unloading bin that communicate sequentially; the shielding module includes an external shield and a neutron shield; the loading module includes a loading body; and sphere inlet passages are provided in the loading body. The unloading and temporary storage device can perform the functions of receiving, temporarily storing, atmosphere switching, and unloading of spherical elements, and also has the safety functions of ensuring geometrical integrity of the spherical elements, radiological protection and residual heat removal.

The present application relates to an unloading and temporary storage device. The unloading and temporary storage device includes a stock bin, a stock bin external member, a stock bin internal member, a shielding module and a loading module; the stock bin includes a barrel and a tank body; the stock bin external member includes a cooling water jacket; the stock bin internal member includes a straight bin, an inclined bin and an unloading bin that communicate sequentially; the shielding module includes an external shield and a neutron shield; the loading module includes a loading body; and sphere inlet passages are provided in the loading body. The unloading and temporary storage device can perform the functions of receiving, temporarily storing, atmosphere switching, and unloading of spherical elements, and also has the safety functions of ensuring geometrical integrity of the spherical elements, radiological protection and residual heat removal.

A cask includes a cask body, an outer cylinder, a plurality of fins, and a plurality of neutron shields. The cask body has a tubular shape around a central axis and is capable of housing fuel assemblies. The outer cylinder has a tubular shape surrounding the cask body. The fins are aligned in a circumferential direction in a tubular space formed between the cask body and the outer cylinder, and connect an outer peripheral surface of the cask body and an inner peripheral surface of the outer cylinder to divide the tubular space into a plurality of divided spaces. The neutron shields contain a neutron shielding material with which the divided spaces are filled. Each neutron shield includes a void portion extending in the axial direction along the central axis. Accordingly, it is possible to reduce stress that may be exerted on the outer cylinder or other components by thermal expansion of the neutron shielding material when the fuel assemblies are housed in the cask.

A cask includes a cask body, an outer cylinder, a plurality of fins, and a plurality of neutron shields. The cask body has a tubular shape around a central axis and is capable of housing fuel assemblies. The outer cylinder has a tubular shape surrounding the cask body. The fins are aligned in a circumferential direction in a tubular space formed between the cask body and the outer cylinder, and connect an outer peripheral surface of the cask body and an inner peripheral surface of the outer cylinder to divide the tubular space into a plurality of divided spaces. The neutron shields contain a neutron shielding material with which the divided spaces are filled. Each neutron shield includes a void portion extending in the axial direction along the central axis. Accordingly, it is possible to reduce stress that may be exerted on the outer cylinder or other components by thermal expansion of the neutron shielding material when the fuel assemblies are housed in the cask.

A module for storing high level radioactive waste includes an outer shell, having a hermetically closed bottom end, and an inner shell forming a cavity and being positioned inside the outer shell to form a space therebetween. At least one divider extends from the top to the bottom of the inner shell to create a plurality of inlet passageways through the space, each inlet passageway connecting to a bottom portion of the cavity. A plurality of inlet ducts each connect at least one of the inlet passageways and ambient atmosphere, and each includes an inlet duct cover affixed atop a surrounding inlet wall, the inlet wall being peripherally perforated. A removable lid is positioned atop the inner shell and has at least one outlet passageway connecting the cavity and the ambient atmosphere, the lid and the top of the inner shell being configured to form a hermetic seal therebetween.

A module for storing high level radioactive waste includes an outer shell, having a hermetically closed bottom end, and an inner shell forming a cavity and being positioned inside the outer shell to form a space therebetween. At least one divider extends from the top to the bottom of the inner shell to create a plurality of inlet passageways through the space, each inlet passageway connecting to a bottom portion of the cavity. A plurality of inlet ducts each connect at least one of the inlet passageways and ambient atmosphere, and each includes an inlet duct cover affixed atop a surrounding inlet wall, the inlet wall being peripherally perforated. A removable lid is positioned atop the inner shell and has at least one outlet passageway connecting the cavity and the ambient atmosphere, the lid and the top of the inner shell being configured to form a hermetic seal therebetween.

Packaging for the transport and/or storage of radioactive materials includes a lateral packaging body around which an outer radiation protection envelope is disposed, which is made from a plurality of individual annular structures stacked on top of each other. Every structure includes an outer annular wall and a radial heat conductive wall, an outer end of which is secured to the wall, and an inner end of which is in contact with the lateral body. Furthermore, two directly consecutive structures delimit an annular cavity housing at least one radiation protection element, the cavity being closed radially towards the outside by the wall of one or both directly consecutive structures, and axially closed by the radial heat-conducting structure of one and the other of the two structures.

Packaging for the transport and/or storage of radioactive materials includes a lateral packaging body around which an outer radiation protection envelope is disposed, which is made from a plurality of individual annular structures stacked on top of each other. Every structure includes an outer annular wall and a radial heat conductive wall, an outer end of which is secured to the wall, and an inner end of which is in contact with the lateral body. Furthermore, two directly consecutive structures delimit an annular cavity housing at least one radiation protection element, the cavity being closed radially towards the outside by the wall of one or both directly consecutive structures, and axially closed by the radial heat-conducting structure of one and the other of the two structures.