# US 11,443,862 B2 · Storage system for radioactive nuclear waste with pressure surge protection > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,443,862 B2 - Document ID: US11443862B2 - Status: Granted - Kind: B2 - Application number: 17/220,560 - Filed: 2021-04-01 - Published: 2021-11-04 - Granted: 2022-09-13 - Earliest claimed: 2020-04-01 - Assignees: Holtec International - Applicants: Holtec International - Inventors: Krishna P. Singh; John D. Griffiths - Web page: https://patentgrep.com/patent/US11443862B2 ## CPC - G21F 5/12: Closures for containers; Sealing arrangements - G21C 19/32: Apparatus for removing radioactive objects or materials from the reactor discharge area, e.g. to a storage place; Apparatus for handling radioactive objects or materials within a storage place or removing them therefrom (disposal of waste material G21F9/00) - G21F 5/012: Fuel element racks in the containers - G21F 5/06: Details of, or accessories to, the containers - G21F 5/10: Heat-removal systems, e.g. using circulating fluid or cooling fins - Y02E 30/30: Nuclear fission reactors - G21F: PROTECTION AGAINST X-RADIATION, GAMMA RADIATION, CORPUSCULAR RADIATION OR PARTICLE BOMBARDMENT; TREATING RADIOACTIVELY CONTAMINATED MATERIAL; DECONTAMINATION ARRANGEMENTS THEREFOR (radiation protection by pharmaceutical means A61K8/00, A61Q17/04; in cosmonautic vehicles B64G1/54; combined with a reactor G21C11/00; combined with X-ray tubes H01J35/16; combined with X-ray apparatus H05G1/02) - G21C: NUCLEAR REACTORS (fusion reactors, hybrid fission-fusion reactors G21B; nuclear explosives G21J) - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract 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. ## Claims ### Claim 1 A storage system for radioactive nuclear waste comprising: a longitudinal axis; a cask comprising a hermetically sealable internal cavity configured to hold an inventory of water sufficient to submerge the nuclear waste therein; and a pressure surge capacitor disposed in the cask, the pressure surge capacitor comprising a vacuum cavity evacuated to sub-atmospheric conditions; wherein the pressure surge capacitor is configured to suppress a pressure surge in the internal cavity of the cask. ### Claim 2 (depends on 1) The system according to claim 1, wherein the pressure surge capacitor further comprises at least one pressure relief device constructed to burst at a predetermined pressure level inside the cask, the pressure relief device when burst placing the vacuum chamber of the pressure surge capacitor in fluid communication with the internal cavity to reduce pressure inside the cask. ### Claim 3 (depends on 1) The system according to claim 1, wherein the pressure surge capacitor has a longitudinally elongated tubular body having a height extending for at least a majority of a height of the internal cavity of the cask. ### Claim 4 (depends on 2) The system according to claim 2, wherein the pressure relief device comprises a rupture disk which seals the vacuum cavity of the pressure surge capacitor. ### Claim 5 (depends on 4) The system according to claim 4, wherein the rupture disk is disposed in a first nd cap of the pressure surge capacitor. ### Claim 6 (depends on 5) The system according to claim 5, further comprising a second pressure relief device comprising a second rupture disk disposed in a second end cap of the pressure surge capacitor which seals the vacuum cavity of the pressure surge capacitor. ### Claim 7 (depends on 4) The system according to claim 4, wherein the rupture disk is recessed in the first end cap and disposed in a flow inlet opening formed through the first end cap into the vacuum chamber. ### Claim 8 (depends on 7) The system according to claim 7, further comprising a disk retaining ring comprising central opening exposing the rupture disk, the disk retaining ring trapping the rupture disk in the inlet opening of the pressure surge capacitor. ### Claim 9 (depends on 1) The system according to claim 1, wherein the pressure surge capacitor comprises an elongated cylindrical sidewall shell extending between opposite ends of the pressure surge capacitor. ### Claim 10 (depends on 1) The system according to claim 1, wherein the cask comprises a sealable lid assembly, a cylindrical circumferential wall comprising radiation shielding material, and a base. ### Claim 11 (depends on 1) The system according to claim 1, wherein the internal cavity of the cask further comprises a fuel basket comprising a plurality of longitudinally elongated fuel storage cells each configured to hold a spent nuclear fuel assembly. ### Claim 12 (depends on 11) The system according to claim 11, wherein the pressure surge capacitor is disposed in a peripheral region of the internal cavity of the cask formed between the fuel basket and the circumferential wall of the cask. ### Claim 13 (depends on 11) The system according to claim 11, wherein the pressure surge capacitor is fixedly attached to the fuel basket. ### Claim 14 (depends on 10) The system according to claim 10, wherein the pressure surge capacitor is disposed between an inner shell and an outer shell of the circumferential wall of the cask. ### Claim 15 (depends on 10) The system according to claim 10, wherein the pressure surge capacitor is affixed to an underside of the lid assembly in the internal cavity of the cask. ### Claim 16 (depends on 1) The system according to claim 1, further comprising a second pressure surge capacitor disposed in the internal cavity of the cask. ### Claim 17 A cask with overpressurization protection for storing nuclear waste fuel comprising: a longitudinal axis; a cask body comprising a removable lid assembly, a base, and a circumferential wall including radiation shielding, the cask body forming a hermetically sealed internal cavity configured for holding spent nuclear fuel submerged in an inventory of water in the internal cavity; a pressure surge capacitor disposed in the cask, the pressure surge capacitor comprising a vacuum cavity evacuated to sub-atmospheric conditions; and the pressure surge capacitor further comprising at least one rupture disk constructed to burst at a predetermined pressure level inside the cask associated with a cask overpressurization condition; wherein the rupture disk when burst allows a portion of the water to fill the vacuum chamber to reduce pressure inside the cask. ### Claim 18 (depends on 17) The system according to claim 17, wherein the pressure surge capacitor has a longitudinally elongated cylindrical body having a height extending for at least a majority of a height of the internal cavity of the cask. ### Claim 19 (depends on 18) The system according to claim 18, wherein the rupture disk is disposed in a first end cap of the pressure surge capacitor. ### Claim 20 (depends on 19) The system according to claim 19, further comprising a second rupture disk disposed in a second end cap of the pressure surge capacitor opposite the first end cap. ### Claim 21 (depends on 17) The system according to claim 17, wherein the internal cavity of the cask has a fuel basket comprising a plurality of longitudinally elongated fuel storage cells of rectilinear cross-sectional shape each configured to hold a spent nuclear fuel assembly; and wherein the pressure surge capacitor is disposed adjacent to the circumferential wall in one of a plurality of peripheral regions of the internal cavity of the cask formed between the fuel basket and the circumferential wall of the cask. ### Claim 22 (depends on 21) The system according to claim 21, wherein the one of the plurality of peripheral regions has a non-rectilinear cross-sectional shape. ### Claim 23 (depends on 17) The system according to claim 17, wherein the pressure surge capacitor is disposed between an inner shell and an outer shell of the circumferential wall of the cask. ### Claim 24 (depends on 17) The system according to claim 17, wherein the pressure surge capacitor is affixed to an underside of the lid assembly in the internal cavity of the cask.