A ventilated apparatus for storing and/or transporting high level radioactive waste. In one aspect, the invention is a ventilated apparatus comprising: an overpack body having an inner surface forming a cavity about a longitudinal axis. A bottom portion of the overpack body is formed by a plurality of segments. Each of the segments extends from a first end wall having a projection to a second end wall having a channel. The segments circumferentially surround a longitudinal axis and are arranged in an intermeshing and spaced-apart configuration such that the projections of the first end walls of the segments project into the channels of the second end walls of adjacent ones of the segments, thereby forming inlet ducts between adjacent ones of the segments. The inlet ducts form air inlet passageways from the external atmosphere to a bottom portion of the cavity.

A system for transporting radioactive materials which may include a containment vessel, a thermal shield, and an impact limiter. The containment vessel may include a vessel body having a storage cavity for receiving radioactive materials, a lid coupled to an upper portion of the vessel body to enclose a top end of the storage cavity, and a lid seal such as a gasket positioned between the lid and the upper portion of the vessel body. The thermal shield may be positioned over the lid. The first impact limiter may be positioned over the thermal shield. The thermal shield may be resistant to high temperatures and may help to protect the integrity of the lid seal when the system is subjected to high temperatures, such as during a fire condition.

A system for transporting radioactive materials which may include a containment vessel, a thermal shield, and an impact limiter. The containment vessel may include a vessel body having a storage cavity for receiving radioactive materials, a lid coupled to an upper portion of the vessel body to enclose a top end of the storage cavity, and a lid seal such as a gasket positioned between the lid and the upper portion of the vessel body. The thermal shield may be positioned over the lid. The first impact limiter may be positioned over the thermal shield. The thermal shield may be resistant to high temperatures and may help to protect the integrity of the lid seal when the system is subjected to high temperatures, such as during a fire condition.

A containment enclosure for shielding an outer cask containing an inner canister loaded with nuclear waste such as spent fuel rods. The enclosure includes a lower base portion at least partially embedded in a concrete pad and an upper radiation shielding portion defined by a shield jacket coupled to and supported by the lower base portion at a circumferential joint. Cavities of the base and shielding portions collectively define a contiguous containment space for the cask. A portion of the cask resides in each of the base and shielding portions which completely enclose and shield the cask to minimize radiation dosage of personnel in the environment surrounding the cask. The cask is cooled by a natural convectively-driven ambient cooling air ventilation system including air inlets at the circumferential joint of the enclosure. The concrete pad may be part of a spent nuclear fuel storage installation comprising plural cask containment enclosures.

A device for storing dangerous materials includes a mount supporting a containment enclosure for containing dangerous materials. The mount includes a frame surmounted by support members that support the enclosure, each support member including a first element secured to the mount and a second element for supporting the enclosure and that is mounted so as to be movable relative to the first element in a substantially vertical sliding direction. The mount includes at least one impact absorber interposed between the two elements, the at least one impact absorber preventing relative movement between the two elements so long as a force applied to the at least one impact absorber by the two elements is no greater than a predetermined threshold. The at least one impact absorber deforms plastically so as to allow the two elements to move relative to each other.

A device for storing dangerous materials includes a mount supporting a containment enclosure for containing dangerous materials. The mount includes a frame surmounted by support members that support the enclosure, each support member including a first element secured to the mount and a second element for supporting the enclosure and that is mounted so as to be movable relative to the first element in a substantially vertical sliding direction. The mount includes at least one impact absorber interposed between the two elements, the at least one impact absorber preventing relative movement between the two elements so long as a force applied to the at least one impact absorber by the two elements is no greater than a predetermined threshold. The at least one impact absorber deforms plastically so as to allow the two elements to move relative to each other.

The invention relates to UF.sub.6 transport and process containers to store UF.sub.6 enriched up to 20 percent by weight .sup.235U in amounts up to 1,500 kg U. The containers include a shell, which has an integral heat exchanger positioned between the exterior and interior surfaces/substrates of the shell. The integral heat exchanger is composed of metal passage voids to pass heat transport fluid. The shell forms an inner chamber, and a partition configuration is positioned within the inner chamber, extending longitudinally along the length of the container, to form a plurality of individual compartments within the inner chamber to store the UF.sub.6. The containers may be produced by additive manufacturing methods.

The invention relates to UF.sub.6 transport and process containers to store UF.sub.6 enriched up to 20 percent by weight .sup.235U in amounts up to 1,500 kg U. The containers include a shell, which has an integral heat exchanger positioned between the exterior and interior surfaces/substrates of the shell. The integral heat exchanger is composed of metal passage voids to pass heat transport fluid. The shell forms an inner chamber, and a partition configuration is positioned within the inner chamber, extending longitudinally along the length of the container, to form a plurality of individual compartments within the inner chamber to store the UF.sub.6. The containers may be produced by additive manufacturing methods.

An assembly for transporting uranium hexafluoride, includes: a sealed inner container, defining a first containment shell intended to be loaded with uranium hexafluoride and having a general cylindrical shape of circular cross-section, the first containment shell being delimited by a lateral wall extending about a longitudinal central axis of the inner container, as well as by two opposite axial end walls crossed by the longitudinal central axis, at least one of the two opposite axial end walls of the sealed inner container being equipped with a uranium hexafluoride filling valve; a sealed outer container delimiting a second containment shell in which the inner container is housed in an extractable manner; and two shock absorber caps removably fastened on respectively two opposite axial ends of the outer container.

An assembly for transporting uranium hexafluoride, includes: a sealed inner container, defining a first containment shell intended to be loaded with uranium hexafluoride and having a general cylindrical shape of circular cross-section, the first containment shell being delimited by a lateral wall extending about a longitudinal central axis of the inner container, as well as by two opposite axial end walls crossed by the longitudinal central axis, at least one of the two opposite axial end walls of the sealed inner container being equipped with a uranium hexafluoride filling valve; a sealed outer container delimiting a second containment shell in which the inner container is housed in an extractable manner; and two shock absorber caps removably fastened on respectively two opposite axial ends of the outer container.