Patent classifications
G21F5/10
CANISTER APPARATUS AND/OR FUEL RACK FOR STORING AND/OR TRANSPORTING SPENT NUCLEAR FUEL
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.
Passive heat removal casks and methods of using the same
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.
Passive heat removal casks and methods of using the same
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.
Storage system for radioactive nuclear waste with pressure surge protection
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.
Disposal container for high-level radioactive waste using multiple barriers and barrier system using thereof
The present invention relates to a disposal container and a storage system for high-level radioactive waste and, more specifically, to a disposal container for high-level radioactive waste using multiple barriers and a barrier system using thereof, the disposal container having the multiple barriers consisting of an inner wall made of carbon steel for excellent corrosion resistance and ease of manufacture, a middle wall made of Inconel, which is bonded to a lateral surface of the inner wall, and an outer wall made of copper, which is bonded to a lateral surface of the middle wall.
Disposal container for high-level radioactive waste using multiple barriers and barrier system using thereof
The present invention relates to a disposal container and a storage system for high-level radioactive waste and, more specifically, to a disposal container for high-level radioactive waste using multiple barriers and a barrier system using thereof, the disposal container having the multiple barriers consisting of an inner wall made of carbon steel for excellent corrosion resistance and ease of manufacture, a middle wall made of Inconel, which is bonded to a lateral surface of the inner wall, and an outer wall made of copper, which is bonded to a lateral surface of the middle wall.
Dual-criterion fuel canister system
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.
Dual-criterion fuel canister system
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.
Spent nuclear fuel canister
A canister for storing spent nuclear fuel includes an elongated shell, baseplate enclosing the bottom end of the shell, and removable top lid bolted to the shell. The shell may have a dual thickness comprising a lower portion with first thickness and upper portion with greater second thickness by comparison. The upper portion is formed by an annular boss defining a fastening portion of the shell including plural threaded bores for engaging the lid bolting. The fastening portion may protrude radially outwards or inwards in different embodiments. The lid has a mounting flange receiving the bolts and is seated on the top end of shell. The mounting flange does not protrude radially beyond the outer surface of the fastener portion to minimize the diameter of the canister for placement inside an outer radiation shielded overpack or cask for transport/storage. The shell may optionally include cooling fins.
Spent nuclear fuel canister
A canister for storing spent nuclear fuel includes an elongated shell, baseplate enclosing the bottom end of the shell, and removable top lid bolted to the shell. The shell may have a dual thickness comprising a lower portion with first thickness and upper portion with greater second thickness by comparison. The upper portion is formed by an annular boss defining a fastening portion of the shell including plural threaded bores for engaging the lid bolting. The fastening portion may protrude radially outwards or inwards in different embodiments. The lid has a mounting flange receiving the bolts and is seated on the top end of shell. The mounting flange does not protrude radially beyond the outer surface of the fastener portion to minimize the diameter of the canister for placement inside an outer radiation shielded overpack or cask for transport/storage. The shell may optionally include cooling fins.