Patents by Inventor Kazuaki KITO

Kazuaki KITO has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10726959
    Abstract: When a power source is lost after an operation stop of a nuclear power plant, a first open/close valve is opened via a first battery at an early stage and steam in a reactor pressure vessel (RPV) is condensed in a suppression pool. The heat of the water in the suppression pool is transmitted to a cooling water pool located below inner space between first and second reactor containment vessels surrounding the RPV. A second open/close valve is opened via a second battery at the early stage and cooling water in a tank is injected into the RPV. After the early stage, a third open/close valve is opened via a third battery, and a cooling medium becomes steam by an evaporator in the RPV, the steam being condensed by a condenser disposed in the inner space to become a liquid of the cooling medium and is returned to the evaporator.
    Type: Grant
    Filed: April 14, 2016
    Date of Patent: July 28, 2020
    Assignee: Hitachi-GE Nuclear Energy, Ltd.
    Inventors: Kenichi Katono, Masao Chaki, Kazuaki Kito
  • Publication number: 20190371481
    Abstract: In view of above problems, an object of the invention is to provide a primary containment vessel venting system having a structure capable of continuously discharging vapor in a primary containment vessel out of the system and continuously reducing pressure of the primary containment vessel without discharging radioactive noble gases to the outside of the containment vessel and without using an enclosing vessel or a power source. In order to achieve the above object, an nuclear power plant of the invention includes a primary containment vessel which includes a reactor pressure vessel, a radioactive substance separation apparatus which is disposed inside the primary containment vessel and through which the radioactive noble gases do not permeate but vapor permeates, a vent pipe which is connected to the radioactive substance separation apparatus, and an exhaust tower which is connected to the vent pipe and discharges a gas, from which a radioactive substance is removed, to the outside.
    Type: Application
    Filed: January 12, 2018
    Publication date: December 5, 2019
    Inventors: Sohei FUKUI, Takahisa MATSUZAKI, Kazuaki KITO, Yoshihiko ISHII, Masataka HIDAKA, Tomohiko IKEGAWA, Katsuki HAMADA
  • Patent number: 10438707
    Abstract: An atomic power plant is provided including a primary containment vessel (PCV) 1, a reactor pressure vessel (RPV) 3, a main steam line 4, two steam safety relief valves (SRVs) 6, a pressure suppression pool (S/P) 8, an SRV exhaust pipe 9 which is connected to a quencher 10, a temperature measuring instrument 12 which measures a temperature inside the quencher 10, an SRV controller 13 which controls opening and closing of the SRVs 6. After a lapse of predetermined time from when the SRV 6 is opened, in a case where it is determined that a temperature detected by the temperature measuring instrument 12 is equal to or smaller than a predetermined threshold value, the SRV controller 13 causes the SRV 6 to which the temperature measuring instrument 12 detecting the temperature leads, to be closed and to be prohibited from being opened.
    Type: Grant
    Filed: January 31, 2017
    Date of Patent: October 8, 2019
    Assignee: Hitachi-GE Nuclear Energy, Ltd.
    Inventors: Kazuaki Kito, Takahisa Matsuzaki, Tomohiko Ikegawa
  • Patent number: 10126075
    Abstract: A heat exchanger has a tubular structure inside of which a medium flows. The heat exchanger includes a liquid film removal structure and a liquid film flowing-down assistance structure. The liquid film removal structure is joined to the tubular structure. The liquid film flowing-down assistance structure is coupled directly to the liquid film removal structure and is arranged between the tubular structure and an adjacent tubular structure and in parallel to the tubular structure.
    Type: Grant
    Filed: January 30, 2015
    Date of Patent: November 13, 2018
    Assignee: Hitachi, Ltd.
    Inventors: Akinori Tamura, Naoyuki Ishida, Kazuaki Kito
  • Publication number: 20170229196
    Abstract: [Problem] Provided is an atomic power plant which can be applied to reactors including existing reactors through a simple method and in which a pressure in a primary containment vessel can be restrained from excessively rising in a case where a steam leakage from an exhaust pipe of a stream safety relief valve occurs. [Solution] There are provided a PCV 1, an RPV 3, a main stream line 4, two SRVs 6, an S/P 8, an SRV exhaust pipe 9 which is connected to a quencher 10, a temperature measuring instrument 12 which measures a temperature inside the quencher 10, an SRV controller 13 which controls opening and closing of the SRVs 6.
    Type: Application
    Filed: January 31, 2017
    Publication date: August 10, 2017
    Inventors: Kazuaki KITO, Takahisa MATSUZAKI, Tomohiko IKEGAWA
  • Publication number: 20160372217
    Abstract: The invention relates to a nuclear power generation plant, and a nuclear reactor containment vessel includes a containment vessel covering a nuclear reactor pressure vessel, an air-cooled heat exchanger which is installed outside the containment vessel and performs heat exchange between steam in the containment vessel and air outside the containment vessel, and a square column-shaped air flow path provided vertically above the air-cooled heat exchanger.
    Type: Application
    Filed: January 6, 2015
    Publication date: December 22, 2016
    Inventors: Akinori TAMURA, Kazuaki KITO
  • Publication number: 20160293281
    Abstract: When a power source is lost after an operation stop of a nuclear power plant, a first open/close valve is opened via a first battery at an early stage and steam in a reactor pressure vessel (RPV) is condensed in a suppression pool. The heat of the water in the suppression pool is transmitted to a cooling water pool located below inner space between first and second reactor containment vessels surrounding the RPV. A second open/close valve is opened via a second battery at the early stage and cooling water in a tank is injected into the RPV. After the early stage, a third open/close valve is opened via a third battery, and a cooling medium becomes steam by an evaporator in the RPV, the steam being condensed by a condenser disposed in the inner space to become a liquid of the cooling medium and is returned to the evaporator.
    Type: Application
    Filed: April 14, 2016
    Publication date: October 6, 2016
    Inventors: Kenichi KATONO, Masao CHAKI, Kazuaki KITO
  • Patent number: 9312034
    Abstract: The invention includes a heat exchanger provided at a position higher than a primary containment vessel; a condensate storage tank disposed below the heat exchanger and above an upper end of a reactor core placed in a reactor pressure vessel; a non-condensate gas discharge line connected to an upper section of the condensate storage tank and to a suppression pool; a second condensate discharge line connected to a position below that section of the condensate storage tank to which a first end of the non-condensate gas discharge line is connected, and to the suppression pool; and a condensate return line connected to a position below that section of the condensate storage tank to which a first end of the second condensate discharge line is connected, and to a side portion of the reactor pressure vessel, the side portion being above the upper end of the core.
    Type: Grant
    Filed: October 22, 2013
    Date of Patent: April 12, 2016
    Assignee: Hitachi-GE Nuclear Energy, Ltd.
    Inventors: Tomohiko Ikegawa, Kazuaki Kito
  • Publication number: 20160091254
    Abstract: Provided is a heat exchanger having improved heat transfer performance. A heat exchanger according to the present invention includes a heat transfer unit configured to perform heat exchange by contact with gas, and a contact surface of the heat transfer unit to be in contact with the gas is provided with a fine structure body which has a height of 10 ?m or less and a surface area of 10 times or more of a smooth surface. The gas desirably has a Reynolds number of 30,000 or more, and the fine structure body is desirably formed of the same material as that of a base material forming the contact surface. Moreover, the fine structure body desirably has heat conductivity equal to or larger than the base material forming the contact surface.
    Type: Application
    Filed: May 17, 2013
    Publication date: March 31, 2016
    Inventors: Toshinori KAWAMURA, Hiroshi NAKANO, Kazuaki KITO, Akinori TAMURA
  • Publication number: 20150276329
    Abstract: According to the invention, there are provided a liquid film removal structure joined to a tubular structure, and a liquid film flowing-down assistance structure arranged between the tubular structure and an adjacent tubular structure and in parallel to the tubular structure.
    Type: Application
    Filed: January 30, 2015
    Publication date: October 1, 2015
    Inventors: Akinori TAMURA, Naoyuki ISHIDA, Kazuaki KITO
  • Publication number: 20140112426
    Abstract: The invention includes a heat exchanger provided at a position higher than a primary containment vessel; a condensate storage tank disposed below the heat exchanger and above an upper end of a reactor core placed in a reactor pressure vessel; a non-condensate gas discharge line connected to an upper section of the condensate storage tank and to a suppression pool; a second condensate discharge line connected to a position below that section of the condensate storage tank to which a first end of the non-condensate gas discharge line is connected, and to the suppression pool; and a condensate return line connected to a position below that section of the condensate storage tank to which a first end of the second condensate discharge line is connected, and to a side portion of the reactor pressure vessel, the side portion being above the upper end of the core.
    Type: Application
    Filed: October 22, 2013
    Publication date: April 24, 2014
    Applicant: Hitachi-GE Nuclear Energy, Ltd.
    Inventors: Tomohiko IKEGAWA, Kazuaki KITO
  • Publication number: 20130077730
    Abstract: A nuclear power plant has a reactor pressure vessel, a primary containment vessel and a passive pressure suppression pool cooling system. The reactor pressure vessel is installed in the primary containment vessel. A pressure suppression pool filled with cooling water is formed in a lower portion of the primary containment vessel. The passive pressure suppression pool cooling system is provided with a steam condensing pool in which cooling water is filled, disposed outside the primary containment vessel, a steam condenser disposed in the steam condensing pool, a steam supply pipe connecting the reactor pressure vessel to the steam condenser, and a condensed water discharge pipe connected to the steam condenser for discharging condensed water generated in the steam condenser. Another end portion of the condensed water discharge pipe is disposed in the pressure suppression pool.
    Type: Application
    Filed: July 19, 2012
    Publication date: March 28, 2013
    Applicant: Hitachi-GE Nuclear Energy, Ltd.
    Inventors: Kazuaki KITO, Masayoshi MATSUURA, Koji ANDO