Fission product getter

Patent metadata

Field	Value
Publication number	US-11501883-B2
Application number	US-202016869579-A
Country	US
Kind code	B2
Filing date	May 7, 2020
Priority date	Mar 8, 2016
Publication date	Nov 15, 2022
Grant date	Nov 15, 2022

Abstract

A getter element includes a getter material reactive with a fission product contained within a stream of liquid and/or gas exiting a fuel assembly of a nuclear reactor. At least one transmission pathway passes through the getter element that is sufficiently sized to maintain a flow of the input stream through the getter element at above a selected flow level. At least one transmission pathway includes a reaction surface area sufficient to uptake a pre-identified quantity of the fission product.

First claim

The invention claimed is:

1. A getter element comprising:
a getter body including a getter material reactive with a nuclear fission product, the getter body further including a void structure through the getter material forming at least one through-channel to facilitate a flow of an input stream through the getter body, the void structure formed by removal of a plurality of void forming structures that were mixed with the getter material in the getter body.

2. The getter element of claim 1 , wherein the at least one through-channel comprises a reaction surface area sufficient to accommodate a chemical reaction between substantially all of the fission product within the input stream over a predetermined time interval.

3. The getter element of claim 1 , wherein the at least one through-channel includes a plurality of voids.

4. The getter element of claim 3 , wherein the plurality of voids have a volume sufficient to maintain a through-flow transmission above a selected flow level despite expansion of the getter material within a predetermined range of expansion.

5. The getter element of claim 1 , wherein the getter material is formed of a metal oxide.

6. The getter element of claim 5 , wherein the metal oxide includes one or more of zirconium oxide, titanium oxide, molybdenum oxide, niobium oxide, tantalum oxide, vanadium oxide, and chromium oxide.

7. The getter element of claim 5 , wherein the metal oxide has an average particle size between 100 nm and 500 nm.

8. The getter element of claim 5 , wherein the metal oxide has an average particle size of less than 100 nm.

9. The getter element of claim 1 , wherein the getter material is configured to react with a fission product that comprises one or more of cesium and a cesium compound.

10. The getter element of claim 1 , wherein the getter body has a density between 25% and 45% of a theoretical density of the getter body.

11. The getter element of claim 1 , wherein the getter body has a density between 50% and 70% of a theoretical density.

12. The getter element of claim 1 , wherein the getter body is formed of a first getter material to facilitate a reaction with a first fission product in the flow of the input stream and a second getter material to facilitate a second reaction with a second fission product in the flow of the input stream.

13. A getter element comprising:
a getter body including a first getter material reactive with a first nuclear fission product, the getter body including a second getter material reactive with a second nuclear fission product, the getter body further including a void structure through the first getter material and the second getter material that forms at least one through-channel to facilitate a flow of an input stream through the getter body, the at least one through-channel comprising a plurality of substantially-spherical voids formed by removal a plurality of void forming structures that were mixed with the first getter material in the getter body.

14. The getter element of claim 13 , wherein the at least one through-channel comprises a reaction surface area sufficient to accommodate a chemical reaction between substantially all of one or more of the first fission product and the second fission product within the input stream over a predetermined time interval.

15. The getter element of claim 13 , wherein the plurality of voids have a volume sufficient to maintain a through-flow transmission above a selected flow level despite expansion of the first getter material and the second getter material within a predetermined range of expansion.

16. The getter element of claim 13 , wherein one or more of the first getter material and the second getter material are formed of a metal oxide.

Assignees

• Terrapower Llc

Inventors

• Eichel Daniel
• Vollmer James M

Classifications

• G21C3/18 Primary

  Internal spacers or other non-active material within the casing, e.g. compensating for expansion of fuel rods or for compensating excess reactivity (interlayers G21C3/20) · CPC title

• G21C3/30

  Assemblies of a number of fuel elements in the form of a rigid unit · CPC title

• Y02E30/30

  Nuclear fission reactors · CPC title

• G21C3/32

  Bundles of parallel pin-, rod-, or tube-shaped fuel elements · CPC title

• G21C3/17 Primary

  Means for storage or immobilisation of gases in fuel elements · CPC title