# US 2021/0280329 A1 · System and method for performing active scanning of a nuclear fuel rod > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0280329 A1 - Document ID: US20210280329A1 - Status: Published application - Kind: A1 - Application number: 17/152,008 - Filed: 2021-01-19 - Published: 2021-09-09 - Earliest claimed: 2016-06-09 - Assignees: Phoenix Aktiengesellschaft - Applicants: Phoenix LLC - Inventors: EVAN R. SENGBUSCH; ARNE V. KOBERNIK; ELI C. MOLL; CHRISTOPHER M. SEYFERT; ROSS F. RADEL; MARK THOMAS; JAKE HECLA - Web page: https://patentgrep.com/patent/US20210280329A1 ## CPC - G21C 17/06: Devices or arrangements for monitoring or testing fuel or fuel elements outside the reactor core, e.g. for burn-up, for contamination (G21C17/08, G21C17/10 take precedence; detecting leaking fuel elements during reactor operation G21C17/04) - G21C 19/00: Arrangements for treating, for handling, or for facilitating the handling of, fuel or other materials which are used within the reactor, e.g. within its pressure vessel - G21G 4/02: Neutron sources - G21B 1/00: Thermonuclear fusion reactors - G21C 3/326: comprising fuel elements of different composition; comprising, in addition to the fuel elements, other pin-, rod-, or tube-shaped elements, e.g. control rods, grid support rods, fertile rods, poison rods or dummy rods - Y02E 30/10: Nuclear fusion reactors - Y02E 30/30: Nuclear fission reactors - G21C: NUCLEAR REACTORS (fusion reactors, hybrid fission-fusion reactors G21B; nuclear explosives G21J) - G21G: CONVERSION OF CHEMICAL ELEMENTS; RADIOACTIVE SOURCES (applications of radiation in general G21H5/00; handling particles, e.g. neutrons, or electromagnetic radiation not otherwise provided for G21K) - G21B: FUSION REACTORS (uncontrolled reactors G21J) - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract A system and method for performing active scanning on a nuclear fuel rod are provided. The system includes an electrically-driven neutron generator including an ion source, an accelerator, and a target; a moderator surrounding the neutron generator and configured to moderate neutrons generated by the neutron generator; a fuel rod channel disposed within the moderator, the fuel rod channel configured to receive a nuclear fuel rod and subject the nuclear fuel rod to a predetermined neutron flux; and a plurality of radiation detectors. When the nuclear fuel rod is subjected to the predetermined neutron flux, neutrons induce a secondary radiation of prompt and delayed gamma emissions, neutron emission, or a combination thereof that are detected by the plurality of radiation detectors to determine an amount of fissile material in the nuclear fuel rod and a spatial distribution of the fissile material along a length of the nuclear fuel rod. ## Claims ### Claim 1 A system for performing active scanning on a nuclear fuel rod, the system comprising: an electrically-driven neutron generator including an ion source, an accelerator, and a target; a moderator surrounding the neutron generator and configured to moderate neutrons generated by the neutron generator; a first fuel rod channel disposed within the moderator, the first fuel rod channel configured to receive a first nuclear fuel rod and subject the first nuclear fuel rod to a predetermined neutron flux; and a plurality of radiation detectors, wherein neutrons induce a secondary radiation of prompt and delayed gamma emissions, neutron emission, or a combination thereof that are detected by the plurality of radiation detectors to determine an amount of fissile material in the first nuclear fuel rod and a spatial distribution of the fissile material along a length of the first nuclear fuel rod. ### Claim 2 (depends on 1) The system of claim 1, wherein the first fuel rod channel is configured to receive the first nuclear fuel rod containing a burnable poison. ### Claim 3 (depends on 2) The system of claim 2, wherein the first fuel rod channel includes an internal epithermal shell having an outer layer comprised of the burnable poison and configured to absorb thermal neutrons. ### Claim 4 (depends on 3) The system of claim 3, wherein the internal epithermal shell further includes an inner layer configured to scatter fast neutrons into an epithermal region, the inner layer being concentric to the outer layer. ### Claim 5 (depends on 4) The system of claim 4, wherein the inner layer is comprised of beryllium. ### Claim 6 (depends on 2) The system of claim 2, wherein the first fuel rod channel is configured to receive the first nuclear fuel rod containing gadolinium or boron. ### Claim 7 (depends on 1) The system of claim 1, wherein the predetermined neutron flux is an epithermal neutron flux, and epithermal neutrons induce the secondary radiation detected by the plurality of radiation detectors. ### Claim 8 (depends on 1) The system of claim 1, wherein the ion source is a microwave ion source or an electron-cyclotron resonance (ECR) ion source. ### Claim 9 (depends on 1) The system of claim 1, wherein the target is a solid target comprised of at least one of titanium, copper, zirconium, uranium, palladium or aluminum. ### Claim 10 (depends on 1) The system of claim 1, wherein the moderator includes a chamber surrounding the target, a neutron moderator surrounding the chamber, and an additional neutron moderator surrounding the neutron moderator. ### Claim 11 (depends on 10) The system of claim 10, wherein the chamber contains a dielectric solid, liquid or gas. ### Claim 12 (depends on 11) The system of claim 11, wherein the chamber contains a fluorinert liquid. ### Claim 13 (depends on 1) The system of claim 1, wherein the first fuel rod channel includes an internal epithermal shell having an outer layer comprised of the burnable poison and configured to absorb thermal neutrons. ### Claim 14 (depends on 1) The system of claim 1, further comprising a second fuel rod channel configured to receive a second nuclear fuel rod and subject the second nuclear fuel rod to a predetermined thermal neutron flux, wherein the second fuel rod channel is disposed within the moderator, and wherein thermal neutrons induce a secondary radiation of gamma emissions, neutron emission, or a combination thereof in the second nuclear fuel rod that are detected by at least one of the plurality of radiation detectors to determine an amount of fissile material and a spatial distribution of the fissile material along a length of the second nuclear fuel rod. ### Claim 15 (depends on 14) The system of claim 14, wherein the second fuel rod channel includes an internal thermal shell having an outer layer comprised of aluminum, and an inner layer comprised of polyethylene. ### Claim 16 (depends on 1) The system of claim 1, further comprising at least one additional fuel rod channel configured to receive a nuclear fuel rod and subject the nuclear fuel rod to an epithermal neutron flux or a thermal neutron flux, wherein neutrons of the epithermal neutron flux or the thermal neutron flux induce a secondary radiation of gamma emissions, neutron emission, or a combination thereof in the nuclear fuel rod that are detected by at least one of the plurality of radiation detectors to determine an amount of fissile material and a spatial distribution of the fissile material along a length of the nuclear fuel rod. ### Claim 17 A method of performing active scanning on a nuclear fuel rod, the method comprising: generating neutrons with an electrically-driven neutron generator including an ion source, an accelerator, and a target; moderating the neutrons with a moderator surrounding the neutron generator; disposing a first nuclear fuel rod in a first fuel rod channel disposed within the moderator; subjecting the first nuclear fuel rod to a predetermined neutron flux to induce a secondary radiation of prompt and delayed gamma emissions, neutron emissions, or a combination thereof; and detecting the secondary radiation with a plurality of radiation detectors to determine an amount of fissile material and a spatial distribution of the fissile material along a length of the first nuclear fuel rod. ### Claim 18 (depends on 17) The method of claim 17, wherein the first nuclear fuel rod contains a burnable poison. ### Claim 19 (depends on 17) The method of claim 17, wherein the first nuclear fuel rod contains gadolinium or boron. ### Claim 20 (depends on 17) The method claim 17, wherein the predetermined neutron flux is an epithermal neutron flux, and epithermal neutrons induce the secondary radiation detected by the plurality of radiation detectors.