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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.