Systems and methods for dry storage and/or transport of consolidated nuclear spent fuel rods

• US 9,558,857 B2
• Filed: 08/02/2013
• Issued: 01/31/2017
• Est. Priority Date: 08/02/2012
• Status: Active Grant

• Current Assignee: NAC International Inc. (Hitachi Zosen Corporation)
• Original Assignee: NAC International Inc. (Hitachi Zosen Corporation)
• Inventors: Subiry, Juan C.
• Primary Examiner(s): O'Connor, Marshall
• Application Number:
  US13/957,919
• Publication Number:
  US 20140039235A1
• Time in Patent Office: 1,278 Days
• US Class Current: 1/1
• CPC Class Codes: G21F 5/012 Fuel element racks in the containers
• CPC Class Codes: G21F 5/10 Heat-removal systems, e.g. using circulating fluid or cooling fins

Abstract

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.

Claims

1. A dry storage canister that stores spent nuclear fuel rods, comprising:

an elongated outer housing, the elongated outer housing extending from a first end to a second end; and

an elongated internal basket provided within the housing, the elongated internal basket extending in a region between the first end and the second end of the elongated outer housing, the internal basket defining multiple elongated tubes forming multiple discrete storage cells, each of the cells and comprising a plurality of the spent nuclear fuel rods that have been separated from their fuel rod assemblies; and

wherein the canister has no neutron absorber material.

2. The canister of claim 1, wherein the outer housing is an elongated cylindrical housing.

3. The canister of claim 1, wherein the storage cells are configured such that a rod packing density of approximately 4 to 6 of the spent fuel rods per square inch can be achieved so that the canister is in less danger of reaching nuclear criticality if a neutron moderator were to enter the canister and so that the nuclear absorber material is not needed in the canister.

4. The canister of claim 1, wherein the internal basket is made of a metal material having a high thermal conductivity.

5. The canister of claim 1, wherein the internal basket is made of one or more of carbon steel, aluminum, or copper.

6. The canister of claim 1, wherein the tubes are cylindrical tubes.

7. The canister of claim 1, wherein the internal basket further comprises at least one elongated spacer disk that extends between the tubes.

8. The canister of claim 1, further comprising a cask in which the canister is placed.

9. The canister of claim 1, wherein the spent nuclear fuel rods are contiguous within each of the cells.

10. The canister of claim 1, further comprising a corrugated divider within at least one of the cells that separates a plurality of the spent nuclear fuel rods.

11. The canister of claim 1, wherein the internal basket is made of a metal material having a high thermal conductivity.