Nuclear Power Plant

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.

What is claimed is: 
     
         1 . A nuclear power plant comprising:
 a first reactor containment vessel internally having a dry well and a pressure suppression chamber mutually isolated, said pressure suppression chamber forming a suppression pool being filled with cooling water;   a reactor pressure vessel disposed in said dry well in said first reactor containment vessel;   a second reactor containment vessel surrounding said first reactor containment vessel and forming a cooling water pool being filled with cooling water at a bottom, said cooling water pool in said second reactor containment vessel adjoining said suppression pool with said first reactor containment vessel intervening between these pools;   a steam discharge apparatus; and   a reactor cooling apparatus,   wherein said steam discharge apparatus has a steam discharge pipe connected to said reactor pressure vessel and immersed in said cooling water in said suppression pool, and a first open/close valve installed in said steam discharge pipe; and   the reactor cooling apparatus has an evaporator installed in said reactor pressure vessel for evaporating a cooling medium, a condenser disposed above said cooling water pool between said first reactor containment vessel and said second reactor containment vessel for condensing steam of said cooling medium generated in said evaporator, a first pipe path connected to said evaporator and said condenser by passing through a side wall of said reactor pressure vessel and a side wall of said first reactor containment vessel, said first pipe path introducing said steam of said cooling medium generated in said evaporator, a second pipe path connected to said condenser and said evaporator by passing through said side wall of the reactor pressure vessel and said side wall of said first reactor containment vessel, said second pipe path introducing a liquid of said cooling medium generated in said condenser to said evaporator, and a second open/close valve installed in either said first pipe path or said second pipe path.   
     
     
         2 . The nuclear power plant according to  claim 1 , comprising a water injection apparatus having a cooling water vessel being filled with cooling water, a cooling water injection pipe connected to said cooling water vessel and said reactor pressure vessel, and an injection valve installed on said cooling water injection pipe. 
     
     
         3 . The nuclear power plant according to  claim 1 , wherein said evaporator is disposed above a regular water level in said reactor pressure vessel. 
     
     
         4 . The nuclear power plant according to  claim 2 , wherein said evaporator is disposed above a regular water level in said reactor pressure vessel. 
     
     
         5 . The nuclear power plant according to  claim 1 , wherein said second pipe path is disposed in said cooling water pool and said suppression pool. 
     
     
         6 . The nuclear power plant according to  claim 2 , wherein said second pipe path is disposed in said cooling water pool and said suppression pool. 
     
     
         7 . The nuclear power plant according to  claim 3 , wherein said second pipe path is disposed in said cooling water pool and said suppression pool. 
     
     
         8 . The nuclear power plant according to  claim 4 , wherein said second pipe path is disposed in said cooling water pool and said suppression pool. 
     
     
         9 . The nuclear power plant according to  claim 1 , wherein a compressor is installed in said first pipe path, and a turbo-motor rotating with steam in said reactor pressure vessel being supplied is connected to said compressor, and said second open/close valve installed in said second pipe path is an expansion valve. 
     
     
         10 . The nuclear power plant according to  claim 2 , wherein a compressor is installed in said first pipe path, and a turbo-motor rotating with steam in said reactor pressure vessel being supplied is connected to said compressor, and said second open/close valve installed in said second pipe path is an expansion valve. 
     
     
         11 . The nuclear power plant according to  claim 1  wherein a battery is connected to said first open/close valve and said second open/close valve. 
     
     
         12 . The nuclear power plant according to  claim 2 , wherein a battery is connected to said injection valve. 
     
     
         13 . The nuclear power plant according to  claim 9 , wherein a third open/close valve is installed on a steam pipe connected to said reactor pressure vessel and said turbo-motor; and a battery is connected to said third open/close valve. 
     
     
         14 . The nuclear power plant according to  claim 10 , wherein a third open/close valve is installed on a steam pipe connected to said reactor pressure vessel and said turbo-motor; and a battery is connected to said third open/close valve.