US20020181642A1 - Zirconium-alloy clad fuel rods containing metal oxide for mitigation of secondary hydriding - Google Patents

Zirconium-alloy clad fuel rods containing metal oxide for mitigation of secondary hydriding Download PDF

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Publication number
US20020181642A1
US20020181642A1 US09/871,972 US87197201A US2002181642A1 US 20020181642 A1 US20020181642 A1 US 20020181642A1 US 87197201 A US87197201 A US 87197201A US 2002181642 A1 US2002181642 A1 US 2002181642A1
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US
United States
Prior art keywords
metal oxide
fuel
container
fuel rod
oxide
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
Application number
US09/871,972
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English (en)
Inventor
Swaminathan Vaidyanathan
John Davies
Steven Wisner
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
General Electric Co
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=25358571&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=US20020181642(A1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Priority to US09/871,972 priority Critical patent/US20020181642A1/en
Application filed by Individual filed Critical Individual
Assigned to GENERAL ELECTRIC COMPANY reassignment GENERAL ELECTRIC COMPANY ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: DAVIES, JOHN H., VAIDYANATHAN, SWAMINATHAN, WISNER, STEVEN B.
Priority to US10/098,563 priority patent/US20020181643A1/en
Priority to DE60215886.9T priority patent/DE60215886T3/de
Priority to ES02253664.3T priority patent/ES2275811T5/es
Priority to EP02253664.3A priority patent/EP1265256B2/en
Priority to JP2002161926A priority patent/JP4301540B2/ja
Publication of US20020181642A1 publication Critical patent/US20020181642A1/en
Priority to US10/330,282 priority patent/US6697450B2/en
Priority to US10/345,167 priority patent/US20030133532A1/en
Abandoned legal-status Critical Current

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    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21C—NUCLEAR REACTORS
    • G21C3/00—Reactor fuel elements and their assemblies; Selection of substances for use as reactor fuel elements
    • G21C3/02—Fuel elements
    • G21C3/04—Constructional details
    • G21C3/16—Details of the construction within the casing
    • G21C3/18—Internal spacers or other non-active material within the casing, e.g. compensating for expansion of fuel rods or for compensating excess reactivity
    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21C—NUCLEAR REACTORS
    • G21C3/00—Reactor fuel elements and their assemblies; Selection of substances for use as reactor fuel elements
    • G21C3/02—Fuel elements
    • G21C3/04—Constructional details
    • G21C3/16—Details of the construction within the casing
    • G21C3/20—Details of the construction within the casing with coating on fuel or on inside of casing; with non-active interlayer between casing and active material with multiple casings or multiple active layers
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E30/00—Energy generation of nuclear origin
    • Y02E30/30—Nuclear fission reactors

Definitions

  • the present invention relates generally to an improved fuel rod design for use in nuclear reactors. More paticularly, the present invention provides nuclear reactor fuel rods in which one or more metal oxides are present within the fuel rod to mitigate secondary hydriding.
  • the present invention seeks to fill that need.
  • the invention is particularly directed to providing improved fuel rod design for use in a Light Water Reactor (LWR).
  • LWR Light Water Reactor
  • the invention provides a method of fabricating a fuel rod in which the tendency for secondary hydriding is mitigated, comprising the step of providing an effective amount of a metal oxide in the fuel rod.
  • the composition of the metal oxide is generally such that if the hydrogen fraction is above the equilibrium condition for the M/MOx couple, a back reaction occurs between the hydrogen and the metal oxide to generate steam and mitigate secondary hydriding.
  • the metal oxide may be selected from oxides of iron, nickel, tin, bismuth, copper, colbalt, chromium, manganese and/or combinations of such oxides.
  • the invention provides a fuel rod with reduced tendency to undergo secondary hydriding, fabricated according to the method of the invention.
  • FIG. 1 is a container with perforations or slits in the wall thereof;
  • FIG. 2 is a fuel rod with the metal oxide within the rod.
  • the present invention resides in the surprising discovery that secondary hydriding in nuclear reactor fuel rods can be sigificantly mitigated, and in some instances substantially eliminated, by providing in the interior of the fuel rod an effective amount of one or more metal oxides.
  • the oxides may be those of iron, nickel, tin, bismuth, copper, colbalt, chromium, manganese and/or combinations of such oxides.
  • suitable metal oxides are iron oxides (Fe 3 O 4 ; Fe 2 O 3 ), nickel oxide (NiO), tin oxide (SnO 2 ), copper oxide (CuO) and bismuth oxide (Bi 2 O 3 ).
  • the invention finds particular applcation to uranium oxide fuel contained within zirconium-alloy based cladding. Such fuel rods are commonly employed in LWRs.
  • the hydrogen:steam ratio within the rod in the region near the metal oxide will be dictated by the thermodynamic equilibrium for the Metal/Metal Oxide (M/MOx) couple, evaluated at the temperature within the fuel rod where the metal oxide is located. If the hydrogen fraction rises above the equilibrium condition for the M/MOx couple, back reaction between the hydrogen and MOx will generate steam and maintain the interior at the posited equilibrium.
  • M/MOx Metal/Metal Oxide
  • the ratio of steam to hydrogen in equilibrium with the metal oxide is such that the steam fraction is above the threshold level for secondary hydriding, secondary hydriding will be mitigated. Since the steam generated by the back reaction between the hydrogen and metal oxide can easily diffuse over a certain length, secondary hydriding can be mitigated even if the metal oxide is present only at discrete intervals.
  • the metal oxide may be present as a coating on the cladding interior surface.
  • the metal oxide may be selected from iron oxides (Fe 3 O 4 ; Fe 2 O 3 ), nickel oxide (NiO), tin oxide (SnO 2 ), copper oxide (CuO) and bismuth oxide (Bi 2 O 3 ).
  • Bismuth oxide is generally employed as it has a lower cross-section for absorption of neutrons than the other oxides.
  • the coating is applied to a thickness in the range of I mil (25 microns) or less, for example 0.25-0.5 mil.
  • the metal oxide may be present as a coating on the fuel pellet surfaces.
  • the metal oxide may be selected from iron oxides (Fe 3 O 4 ; Fe 2 O 3 ), nickel oxide (NiO), tin oxide (SnO 2 ), copper oxide (CuO) and bismuth oxide (Bi 2 O 3 ).
  • Bismuth oxide is generally employed as it has a lower cross-section for absorption of neutrons than the other oxides.
  • the coating is applied to a thickness in the range of I mil (25 microns) or less, for example 0.25-0.5 mil.
  • the metal oxide may be present as individual pellets or as wafers between fuel pellets, or at the bottom of the fuel stack or at the top of the fuel stack or combinations thereof.
  • the individual pellets or wafers will be of nearly the same geometry (diameter) as the pellet, possibly a little larger. In the instance where they are present between the fuel pellets, the pellet or wafer thickness will depend upon the number of pellets or wafers used.
  • the pellets or wafers are generally fabricated by sintering the metal oxide powder selected from iron oxides (Fe 3 O 4 ; Fe 2 O 3 ), nickel oxide (NiO), tin oxide (SnO 2 ), copper oxide (CuO) and bismuth oxide (Bi 2 O 3 ).
  • the metal oxide powder selected from iron oxides (Fe 3 O 4 ; Fe 2 O 3 ), nickel oxide (NiO), tin oxide (SnO 2 ), copper oxide (CuO) and bismuth oxide (Bi 2 O 3 ).
  • FIG. 1 shows a container 2 with perforations or slits 4 in the wall thereof which provide free access to the surrounding gases.
  • the container is typically fabricated of a material that does not react with the metal oxide, such as stainless steel.
  • the container wall has a thickness of 10 mils or less and an outside diameter which is essentially the same as fuel pellets, or slightly larger.
  • the metal oxide may be present in the container 2 as a powder or pellet, as described above.
  • the metal oxide may be discretely distributed (rather than in a continuous manner) along the fuel rod.
  • the metal oxide may be in any of the configurations described in the first through fourth embodiments above.
  • FIG. 2 there is shown a fuel rod 6 comprising an outer cladding 8 and a fuel pellet stack 10 .
  • a container 2 as described above, is provided at the bottom of and retained in place by bottom end cap 12 and the fuel stack 10 containing metal oxide.
  • FIG. 2 illustrates the situation where the container is at the bottom of the fuel stack.
  • a similar container may also be placed at the top of the fuel stack.
  • a container is placed at the bottom of the fuel stack, and a further container may optionally be present at the top of the stack.
  • a plenum and a retainer spring (not shown) which presses down on the container to hold it in place.
  • the specific metal oxide to be used for secondary hydriding mitigation may be selected from the oxides of Ni, Fe, Sn, Bi, Cu, Co, Cr, and Mn.
  • the metal oxide is typically present in each fuel rod in an amount of up to about 15 grams, more usually up to about 12 grams, for example 2 to 10 grams.
  • the specific metal oxide to be chosen is to be based on whether the metal oxide reacts with hydrogen rapidly enough.
  • the rapidity of this reaction must be such that the rate is sufficiently fast so that it can counteract the rate at which hydrogen is produced in the forward reaction.
  • a further factor in the choice of metal oxide is whether the equilibrium hydrogen:steam ratio is sufficiently rich in steam to avert secondary hydriding. Generally, if the pressure of steam is greater than about 5% of the hydrogen pressure, it is believed that hydriding can be avoided.
  • the oxides of iron, nickel, tin, bismuth and copper are employed.
  • Bismuth oxide (Bi 2 O 3 ) is typically employed when the metal oxide is to be placed in the fuel pellet column space as it minimizes parasitic neutron absorption from the introduction of metal oxide into the core.
  • Copper oxide (CuO) is typically employed when the metal oxide is to be located at the bottom or at the top of the fuel column where parasitic neutron absorption is not a prime consideration. Oxides of specific isotopes of these materials that minimize parasitic absorption may also be employed.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • General Engineering & Computer Science (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Monitoring And Testing Of Nuclear Reactors (AREA)
  • Catalysts (AREA)
  • Solid-Sorbent Or Filter-Aiding Compositions (AREA)
US09/871,972 2001-06-04 2001-06-04 Zirconium-alloy clad fuel rods containing metal oxide for mitigation of secondary hydriding Abandoned US20020181642A1 (en)

Priority Applications (8)

Application Number Priority Date Filing Date Title
US09/871,972 US20020181642A1 (en) 2001-06-04 2001-06-04 Zirconium-alloy clad fuel rods containing metal oxide for mitigation of secondary hydriding
US10/098,563 US20020181643A1 (en) 2001-06-04 2002-03-18 Zirconium-alloy clad fuel rods containing metal oxide for mitigation of secondary hydriding
DE60215886.9T DE60215886T3 (de) 2001-06-04 2002-05-24 Brennstab mit einer Hülle aus einer Zirkoniumlegierung und beinhaltend ein Metalloxid zum Begrenzen der Hydrierung
ES02253664.3T ES2275811T5 (es) 2001-06-04 2002-05-24 Varillas de combustible envainadas de aleación de circonio que contienen óxido metálico para atenuación de hibridación secundaria
EP02253664.3A EP1265256B2 (en) 2001-06-04 2002-05-24 Zirconium-alloy clad fuel rods containing metal oxide for mitigation of secondary hydriding
JP2002161926A JP4301540B2 (ja) 2001-06-04 2002-06-03 燃料棒及びその製造方法
US10/330,282 US6697450B2 (en) 2001-06-04 2002-12-30 Zirconium-alloy clad fuel rods containing metal oxide for mitigation of secondary hydriding
US10/345,167 US20030133532A1 (en) 2001-06-04 2003-01-16 Zirconium-alloy clad fuel rods containing metal oxide for mitigation of secondary hydriding

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US09/871,972 US20020181642A1 (en) 2001-06-04 2001-06-04 Zirconium-alloy clad fuel rods containing metal oxide for mitigation of secondary hydriding

Related Child Applications (3)

Application Number Title Priority Date Filing Date
US10/098,563 Continuation US20020181643A1 (en) 2001-06-04 2002-03-18 Zirconium-alloy clad fuel rods containing metal oxide for mitigation of secondary hydriding
US10/098,563 Division US20020181643A1 (en) 2001-06-04 2002-03-18 Zirconium-alloy clad fuel rods containing metal oxide for mitigation of secondary hydriding
US10/330,282 Continuation US6697450B2 (en) 2001-06-04 2002-12-30 Zirconium-alloy clad fuel rods containing metal oxide for mitigation of secondary hydriding

Publications (1)

Publication Number Publication Date
US20020181642A1 true US20020181642A1 (en) 2002-12-05

Family

ID=25358571

Family Applications (4)

Application Number Title Priority Date Filing Date
US09/871,972 Abandoned US20020181642A1 (en) 2001-06-04 2001-06-04 Zirconium-alloy clad fuel rods containing metal oxide for mitigation of secondary hydriding
US10/098,563 Abandoned US20020181643A1 (en) 2001-06-04 2002-03-18 Zirconium-alloy clad fuel rods containing metal oxide for mitigation of secondary hydriding
US10/330,282 Expired - Fee Related US6697450B2 (en) 2001-06-04 2002-12-30 Zirconium-alloy clad fuel rods containing metal oxide for mitigation of secondary hydriding
US10/345,167 Abandoned US20030133532A1 (en) 2001-06-04 2003-01-16 Zirconium-alloy clad fuel rods containing metal oxide for mitigation of secondary hydriding

Family Applications After (3)

Application Number Title Priority Date Filing Date
US10/098,563 Abandoned US20020181643A1 (en) 2001-06-04 2002-03-18 Zirconium-alloy clad fuel rods containing metal oxide for mitigation of secondary hydriding
US10/330,282 Expired - Fee Related US6697450B2 (en) 2001-06-04 2002-12-30 Zirconium-alloy clad fuel rods containing metal oxide for mitigation of secondary hydriding
US10/345,167 Abandoned US20030133532A1 (en) 2001-06-04 2003-01-16 Zirconium-alloy clad fuel rods containing metal oxide for mitigation of secondary hydriding

Country Status (5)

Country Link
US (4) US20020181642A1 (https=)
EP (1) EP1265256B2 (https=)
JP (1) JP4301540B2 (https=)
DE (1) DE60215886T3 (https=)
ES (1) ES2275811T5 (https=)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090238322A1 (en) * 2008-03-24 2009-09-24 Jin Liu Fuel rod and assembly containing an internal hydrogen/tritium getter structure
WO2013191743A1 (en) * 2012-02-17 2013-12-27 The Massachusetts Institute Of Technology Surface modification of cladding material
CN106663475A (zh) * 2014-04-14 2017-05-10 先进核反应堆概念有限责任公司 分散在金属合金基质中的陶瓷核燃料

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SE517733C2 (sv) * 2000-11-02 2002-07-09 Westinghouse Atom Ab Bränslepatron och rörformigt element för en nukleär kokarvattenreaktor
US20080013666A1 (en) * 2006-07-17 2008-01-17 Swaminathan Vaidyanathan Method for in-situ production of hyperstoichiometric oxide fuel
SE532185C2 (sv) 2007-04-10 2009-11-10 Westinghouse Electric Sweden Förfarande för att driva en reaktor hos en kärnanläggning
JP4909951B2 (ja) * 2008-07-14 2012-04-04 株式会社東芝 中性子遮蔽体
US9666310B1 (en) 2013-03-19 2017-05-30 U.S. Department Of Energy Accident-tolerant oxide fuel and cladding
US10803999B2 (en) * 2017-03-17 2020-10-13 Westinghouse Electric Company Llc Coated U3Si2 pellets with enhanced water and steam oxidation resistance
US11404177B2 (en) 2019-10-23 2022-08-02 Battelle Energy Alliance, Llc Reactor fuel pellets with thermally-conductive inserts, and related reactor fuel pellet arrangements

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090238322A1 (en) * 2008-03-24 2009-09-24 Jin Liu Fuel rod and assembly containing an internal hydrogen/tritium getter structure
EP2105934A3 (en) * 2008-03-24 2009-12-30 Westinghouse Electric Company LLC Fuel rod and assembly containing an internal hydrogen/tritium getter structure
WO2013191743A1 (en) * 2012-02-17 2013-12-27 The Massachusetts Institute Of Technology Surface modification of cladding material
CN106663475A (zh) * 2014-04-14 2017-05-10 先进核反应堆概念有限责任公司 分散在金属合金基质中的陶瓷核燃料

Also Published As

Publication number Publication date
EP1265256B2 (en) 2015-12-09
JP4301540B2 (ja) 2009-07-22
US20030133531A1 (en) 2003-07-17
US6697450B2 (en) 2004-02-24
DE60215886T2 (de) 2007-09-06
DE60215886T3 (de) 2016-04-28
US20030133532A1 (en) 2003-07-17
DE60215886D1 (de) 2006-12-21
EP1265256B1 (en) 2006-11-08
EP1265256A1 (en) 2002-12-11
ES2275811T3 (es) 2007-06-16
US20020181643A1 (en) 2002-12-05
JP2003004882A (ja) 2003-01-08
ES2275811T5 (es) 2016-02-23

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Owner name: GENERAL ELECTRIC COMPANY, NEW YORK

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:VAIDYANATHAN, SWAMINATHAN;DAVIES, JOHN H.;WISNER, STEVEN B.;REEL/FRAME:012214/0781

Effective date: 20010322

STCB Information on status: application discontinuation

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