Discussion Regarding Global Nuclear Fuel-Americas Patent Portfolio
- By Duncan Williams -
In response to the United States’ renewed interest in nuclear power, many companies in the nuclear power industry have begun taking steps to protect their intellectual property rights. For example, Global Nuclear Fuel-Americas (GNFA), a joint venture between GE Energy, Hitachi, and Toshiba has quickly amassed an impressive patent portfolio. Formed in 2001, GNFA manufactures nuclear fuel for customers in Europe, Mexico, Taiwan and the United States. In addition to operating a nuclear reactor in Wilmington, North Carolina, GNFA works with Global Nuclear Fuel-Japan to develop various materials and methods. Over the last five years, GNFA has been filing a dizzying number of patent applications relating to various aspects of the nuclear industry, resulting in a total of 29 patents.
Some of the patents in GNFA’s patent portfolio include technology relating to nuclear reactor simulators. For example U.S. Patent No. 7,620,139, titled “Method of improving nuclear reactor performance during reactor core operation,” issued on November 17, 2009, is directed to simulating the effects of inserting control rods into the reactor. Control rods in nuclear reactors are made of a neutron-absorbing material in order to catch the neutrons produced by the nuclear fuel during the fission process. Since neutrons are necessary to continue the fission process, the sudden lack of neutrons in the reactor caused by the control rod insertion effectively shuts down the reactor. This patent describes methods of predicting the behavior of the reactor during these control rod insertions.
Another patent, U.S. Patent No. 7,532,698, issued on May 12, 2009, describes a method of predicting how many neutrons will be created and lost during the fission process given numerous reactor parameters. Still another patent, U.S. Patent No. 7,613,272, titled “Methods of using fuel bundle groups as evaluation constraints,” issued on November 3, 2009, describes methods of designing a reactor core based on inputs regarding the characteristics of the fuel assembly, also known as a fuel bundle.
Other patent applications are directed towards various components located inside the reactor core. For example, U.S. Patent Application No. 20090022259, published on January 22, 2009, describes a wear-resistant coating that can be placed on fuel rods. Fuel rods are located in the reactor core and contain the nuclear fuel that creates and sustains the fission process. The nuclear fuel in this type of reactor is made of uranium dioxide pellets which are stacked on top of one another inside the fuel rod. The fuel rod is then sealed so that the nuclear fuel, as well as the fission products produced during fission, remain inside the fuel rod. As seen in the diagram from the patent application, the fuel rods are formed into a fuel assembly (10). The fuel rods (16) are held in place by a square-shaped spacer grid (20).
The patent application indicates that this is a boiling water reactor (BWR) as opposed to a pressurized water reactor (PWR). Although both reactor types use water as a coolant, the BWR allows the water to boil as it is heated. In contrast, the PWR pressurizes the entire coolant system in order to raise the boiling point of the water so that boiling is prevented. Although corrosion takes place to some degree in every reactor plant, the boiling that takes place in BWRs tends to concentrate unwanted particulates near the fuel rods (e.g., the spacer grids (20)). The patent indicates that corrosive particulates become hardened from irradiation and can cause severe damage upon collision with the fuel rods.
In order to prevent the free-floating particulates from damaging the fuel rods, the patent application describes several different mixtures of coatings as well as methods for applying them to the outer surface of the fuel rods. For example, the patent application describes a hard metallic coating forming a metal matrix having a thickness of 25 microns to 175 microns and made of NiCrAlY, NiCr, FeCrAlY, FeCr, or a combination of these materials. This coating provides increased corrosion resistance, toughness and adhesion properties. Because of the improved adhesion properties, other materials can be bonded to this coating. For example, the patent application describes combining the hard metallic material with a ceramic or metal oxide material made from zirconium oxide, aluminum oxide, chromium oxide, titanium oxide, or chromium carbide.
The resulting mixture is known as a cermet layer, a combination of ceramic and metallic materials. Cermet material combines the properties from ceramics (hard and resistant to high temperatures) with the properties from metals (flexible and non-brittle). Cermets are currently used to make electrical components, such as resistors and capacitors, which are capable of withstanding high temperatures.
Another patent application suggests that GNFA is focusing its research efforts relating to coating components in the reactor core. U.S. Patent Application No. 20090285350, published on November 19, 2009, describes cladding materials to be placed on the outer covering of a fuel assembly. As seen in the diagram, the elongated square covering encloses the fuel assembly discussed above. The fuel assembly covering is made of a core layer (104) with a cladding layer (102) on both sides. The core layer (104) is designed to be resistant to deformation due to irradiation, while the cladding layer (102) is corrosion resistant. The two layers are made from alloys containing various percentages of zirconium, tin, niobium, iron, and chromium.
Another patent application, U.S. Patent No. 20060048869, titled “Non-heat treated zirconium alloy fuel cladding and a method of manufacturing the same,” relates to methods of manufacturing materials. This patent application describes a process for manufacturing zirconium-based alloys typically used in reactor components. Zirconium-based alloys are typically formed by submerging the alloy in a heat solution, and then rapidly quenching in order to obtain the characteristics necessary for nuclear reactor components. However, the machinery and materials used in this process are costly - which led GNFA to develop non-heat treated components. The patent application indicates that manufacturing materials having certain percentages of zirconium, iron, chromium, nickel and tin react more favorably to the non-heat treatment process.
Filed over 5 years ago, this patent application has been rejected by the Patent Office for being obvious. In response, NGFA has filed an appeal at the Board of Patent Appeals and Interferences (BPAI). The BPAI is an agency, not a court, and overturns about 50% of the patent examiner’s decisions. Thus, appealing to the BPAI is a necessary part of the process for many patent applicants who have received a final rejection. GNFA’s determination to pursue protection for this process underlines its importance to GNFA.
Another patent application that has been rejected by the Patent Office is U.S. Patent No. 20080089461, titled “Fuel rods for nuclear reactor fuel assemblies and methods of manufacturing thereof.” This patent application describes a fuel rod containing pellets having varying concentrations of uranium dioxide. According to the patent application, organizing the reactor core into zones relating to the uranium concentrations of the fuel pellets results in a more even power distribution throughout the reactor core lifetime. This, in turn, leads to a longer period of time before the fuel rods need to be replaced. NGFA is currently appealing the Patent Office’s final rejection of this application to the BPAI.
NGFA’s intellectual property portfolio highlights the current trend in the industry of protecting all aspects of the company’s business. When designing an intellectual property strategy for a company in the nuclear industry, one should consider protecting the company’s reactor design activities, reactor simulation research, methods of operating reactors, as well as the process and methods relating to manufacturing reactor parts.
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About Duncan WilliamsDuncan Williams graduated from the University of Florida in 1994 with a B.S. in Physics, and a minor in mathematics. Upon graduation, he was commissioned in the U.S. Navy where he completed training in the Navy’s Nuclear Propulsion program. He then served onboard an 
aircraft carrier, the USS Theodore Roosevelt, as a reactor control division officer. Onboard, he was responsible for the operation and maintenance of the electrical and mechanical components that make up the reactor control systems. This includes the control rod drive mechanisms, the reactor safety and emergency systems, the reactor coolant pump systems, and the ion exchangers. He also developed and implemented ship-wide reactor safety drills in order to educate sailors in reactor safety.
Duncan then transferred to the U.S. Naval Academy, where he served as a senior instructor teaching Thermodynamics to senior cadets. While serving as an instructor at the Naval Academy, Duncan attended night law school at the George Washington University Law School. After receiving his J.D. in 2004, he resigned his commission and began working as an intellectual property associate with Kenyon & Kenyon LLP. While at Kenyon & Kenyon, he drafted numerous patents relating to medical devices, electronic devices, telecommunications, as well as other technologies. He also has experience in all stages of patent litigation, and has represented numerous Fortune 500 companies in protecting their intellectual property rights. Duncan is currently an intellectual property associate at Blank Rome LLP.
If you have questions, comments, or know of a patent that you think Duncan should review E-mail Duncan Williams>> duncan@nuclearstreet.com