Primary Inventor: Krishna P. Singh
Contributing Inventor(s): Stephen Agace, R. Mahorter
Date: Aug. 22, 2023
Status: Granted
Jurisdiction: US
Assignee: Holtec International
Equipment Type: HI-STORM FW
Docket Number: HOL-148
Application Number: 17/470,053
Patent Number: US 11,735,327 B2

Prior Publication Data: US 2022/0406481 A1

Related U.S. Application Data: Provisional application No. 63/223,578, filed on Jul. 20, 2021, provisional application No. 63/211,234, filed on Jun. 16, 2021.

Abstract: A natural passively cooled ventilated cask includes a cavity which holds a canister containing heat and radiation emitting spent nuclear fuel assemblies or other high level wastes. Ambient ventilation or cooling air is drawn inwards beneath the cask and vertically upwards into a lower portion of the cavity through air inlet ducts formed integrally with a bottom canister support structure coupled to the cask. The air heated by the canister flows upwards in the cavity and returns to atmosphere through air outlet ducts in the cask lid. Air circulation is driven via natural convective thermo-siphon flow. Structural standoff members elevate the bottom of the cask above a concrete base pad forming an air inlet plenum beneath the canister support structure. The lateral sidewall surface of the cask has no penetrations for the air inlets, which eliminates any streaming path for radiation emanating from the spent nuclear fuel.