摘要:
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.
摘要:
A cask liner includes a hollow cylinder comprising a boron-containing composition. The hollow cylinder has no longitudinal joints. The hollow cylinder may be formed as a single unit by isostatic pressing, for example by hot isostatic pressing (HIP) of a blend of a boron-containing powder and an aluminum or aluminum alloy powder which is blended by mechanical alloying. Casked nuclear fuel includes a nuclear fuel rod comprising uranium, which is disposed in or extends through the hollow cylinder of the cask liner.
摘要:
A neutron absorber apparatus for use in restoring reactivity control to a nuclear fuel rack. The apparatus comprises an elongated tubular insert assembly configured for insertion in a storage cell of the rack. First and second absorber plates, each formed of a boron-containing material, are coupled together by upper and lower stiffening bands at the insert extremities and form a longitudinally-extending cavity configured for receiving a fuel assembly. The absorber plates and stiffening bands may have a rectilinear cross sectional configuration in one embodiment. At least one elastically deformable locking protrusion mounted proximate to the lower end of the absorber plates lockingly engages an available lower edge disposed in the cell sidewall above its bottom end. This fixes the tubular insert axially in the cell, thereby preventing its withdrawal after installing the insert. In one embodiment, the edge may be the bottom of existing absorber sheathing in the cell.
摘要:
A packaging system for radioactive waste is robust, highly functional, and can be used for nearly all radioactive waste streams that require shielded packaging. The packaging system includes a modular container that is configured to receive modular shielding inserts. The packaging system can be used to store, transport, and dispose of radioactive waste.
摘要:
A canister apparatus, basket apparatus and combinations thereof for transporting and/or storing high level radioactive waste, such as spent nuclear fuel. In one embodiment, the invention can be a basket apparatus for supporting a plurality of spent nuclear fuel rods within a containment structure, the basket apparatus comprising a plurality of disk-like grates, each disk-like grate having a plurality of cells formed by a gridwork of beams; and means for supporting the disk-like grates in a spaced arrangement with respect to one another and so that the cells of the disk-like grates are aligned.
摘要:
A shipping container comprises a tubular or cylindrical shell having a closed end and an open end, a top end-cap removably secured to the open end of the tubular or cylindrical shell, and at least one fuel assembly compartment defined inside the shell. Each fuel assembly compartment includes elastomeric sidewalls and is sized and shaped to receive an unirradiated nuclear fuel assembly through the open end of the shell. The shipping container may further include a divider component, for example having a cross-shaped cross-section with ends of the cross secured to inner walls of the shell, and the divider component and the inner walls of the shell define the fuel assembly compartments. To load, the shipping container is arranged vertically and an unirradiated nuclear fuel assembly is loaded through the open end of the shell into each compartment, after which the open end is closed off by securing the top end-cap.
摘要:
An apparatus for supporting radioactive fuel assemblies, such as spent nuclear fuel. In one aspect, the invention is an apparatus, which can be in the form of a fuel rack having adjustable height pedestals.
摘要:
A reactivity control device for storing nuclear fuel includes a top tube sheet, plurality of neutron absorber rods fixedly attached to the sheet, and a floating guide plate slideably mounted on the absorber rods for upward and downward movement between a lower position and an upper position. The reactivity control device is insertable into a spent fuel assembly in either wet storage in a spent fuel pool or dry storage in a canister. The absorber rods are inserted into empty guide tubes when the fuel assembly is removed from the nuclear fuel core normally occupied by control rods when in the reactor vessel. During installation, the device is lowered to insert the absorber rods into the guide tubes. The guide plate first engages the fuel assembly as the rods continue to slide through the plate until the tube sheet then engages the plate signaling the device is fully installed.
摘要:
An integrated storage, transportation and disposal system for used fuel assemblies is provided. The system includes a plurality of sealed canisters and a cask sized to receive the sealed canisters in side by side relationship. The plurality of sealed canisters include an internal basket structure to receive a plurality of used fuel assemblies. The internal basket structure includes a plurality of radiation-absorbing panels and a plurality of hemispherical ribs generally perpendicular to the canister sidewall. The sealed canisters are received within the cask for storage and transportation and are removed from the cask for disposal at a designated repository. The system of the present invention allows the handling of sealed canisters separately or collectively, while allowing storage and transportation of high burnup fuel and damaged fuel to the designated repository.
摘要:
In one embodiment, a system and method for dry storage comprises removing spent fuel rods from their fuel rod assemblies and placing the freed fuel rods in a storage cell of a dry storage canister with a high packing density and without a neutron absorber material present.