JPH0245159B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a nuclear reactor containment vessel.

Conventionally, a so-called over-under type reactor containment vessel for accommodating a reactor pressure vessel has been used. This thing has a flask shape as a whole, and the inside is divided into upper and lower parts by a diaphragm floor.
The upper part is a dry well, the lower part is a suppression chamber, and the reactor pressure vessel is housed in the upper dry well. A large number of vent pipes are installed that penetrate the diaphragm floor and are inserted into the suppression chamber, and in the event that steam leaks due to pipe breakage, etc., this steam will be channeled through the vent pipes. It was designed to be discharged into the pool water in the suppression chamber and condense, thereby preventing an increase in internal pressure. However, this system had the problem of increasing the overall height and size because a dry well was formed above the suppression chamber in which the reactor pressure vessel was housed.
In order to eliminate such problems, a nuclear reactor containment vessel as shown in FIG. 1 has been developed. This device has a lower dry well 1 formed in the center of the lower part of the reactor containment vessel, a suppression chamber 2 formed around this lower dry well 1, and a diaphragm floor 3 in the upper part for suppression. The reactor pressure vessel 5 is divided into an upper dry well 4 separated from the chamber 2, and the lower part of the reactor pressure vessel 5 is housed in the lower dry well 1, and the upper part is housed in the upper dry well 4. A large number of vent pipes 6 are provided passing through the diaphragm floor 3, and the lower ends of these vent pipes 6 are immersed in the pool water A within the suppression chamber 2. Also, a communication passage 7 is provided that communicates the upper dry well 4 and the lower dry well 1, and steam leaked from the lower dry well 1 flows to the upper dry well 4 via the communication passage 7. It is configured to be sent from the dry well 4 into the suppression chamber 2 via vent pipes 6. By the way, if a pipe rupture occurs in such a system, pool water A is sprayed into the reactor pressure vessel 5 by the core cooling system pump 8 to cool the reactor core, and also to cool the reactor containment vessel. Pool water A is sprayed into the upper dry well 4 by the system pump 9 to cool the inside of the reactor containment vessel. However, in this case, the pool water A sprayed in the upper dry well 4 is on the diaphragm floor 3.
is collected in the lower dry well 1 via the communication path 7...
There was a problem that the lower dry well 1 was flooded with water. For this reason, the control rod drive mechanism 1 housed in this lower dry well 1
There was a problem where important equipment such as 0 was submerged in water and its integrity was compromised. In addition, since the pool water A accumulated in the lower dry well 1 no longer contributes to steam condensation, an excess amount of pool water A must be stored in the suppression chamber 2. There was a problem where the tether chamber 2 became larger.

The present invention has been made based on the above-mentioned circumstances, and its purpose is to obtain a reactor containment vessel in which water sprayed in the upper dry well does not flow into the lower dry well.

The first aspect of the present invention will be described below with reference to the embodiments shown in FIGS. 2 and 3. FIG. 2 and FIG. 3 show one embodiment, and in the figures, 101 is the main body of the containment vessel. A middle cylindrical partition wall 102 is formed at the center of the lower part of the containment vessel main body 101, and the inside of this partition wall 102 covers the lower dry well 1.
03, the outer periphery of this partition wall 102 and the containment vessel main body 1
Suppression chamber 1 is between the inner peripheral surface of 01
It is formed in 04. Further, the upper end of the suppression chamber 104, that is, the upper end of the partition wall 102, and the inner circumferential surface of the containment vessel body 101 are partitioned by an annular diaphragm floor 105, and the inner upper part of the containment vessel body 101 is It is formed in the upper dry well 106. Then, a plurality of vent pipes 1 pass through the diaphragm floor 105.
07... are provided, the lower ends of these vent pipes 107... are immersed in the pool water A in the suppression chamber 104, and the upper ends protrude from the upper surface of the diaphragm floor 105, and the upper dry well 1
It opens into 06. A pedestal 108 that also serves as a heat shield wall is connected from the upper end of the partition wall 102.
A reactor pressure vessel 109 is installed on the pedestal 108 . The lower part of the reactor pressure vessel 109 is accommodated in the lower dry well 103, and the lower dry well 103 also accommodates a control rod drive mechanism 110 and the like. In addition, in the unlikely event that a pipe rupture occurs, the pool water A will be transferred to the core cooling system pump 11.
1 into the reactor pressure vessel 109 to cool the reactor core, and is sprayed into the upper dry well 106 by the reactor containment vessel spray system pump 112 to cool the inside of the reactor containment vessel. It is composed of Also, communication passages 113 are formed at the upper end of the partition wall 102, and these communication passages 113 communicate the upper dry well 106 and the lower dry well 103, causing steam leakage in the lower dry well 103. In this case, the steam flows to the upper dry well 106 through these communication passages 113...
It is configured to be sent from the air through the vent pipes 107 into the suppression chamber 104. Further, these communication passages 113 are used as passages for passing piping, cables, and the like. and,
The upper end portions of these communicating passages 113... are open to the upper surface of the diaphragm floor 105, and an annular partition wall 1 is formed surrounding the openings of these communicating passages 113...
14 are provided. And this partition wall 11
4 is formed higher than the upper end of the vent pipe 107, so that the open end of the communication passage 113 in the upper dry well 106 is substantially higher than the upper end of the vent pipe 107. It is configured.

In the first embodiment of the present invention configured as described above, since the suppression chamber 104 is arranged around the lower dry well 103, the height of the entire reactor containment vessel is reduced, and the overall height of the reactor containment vessel is reduced. It is also downsized. If steam leaks in the upper dry well 106, this steam will be transferred to the suppression chamber 104 through the vent pipes 107.
It is discharged and condenses into the pool water A inside the reactor containment vessel, thereby limiting the pressure rise inside the reactor containment vessel. Additionally, if steam leaks from the lower dry well 103, this steam flows to the upper dry well 106 via the communication passages 113, and further vent pipes 107...
It is sent to the suppression chamber 104 via the reactor and condensed to limit the pressure rise inside the reactor containment vessel. In such a case, a portion of the pool water A is sent into the reactor pressure vessel 109 by the core cooling system pump 111 to cool the reactor core, and a part of the pool water A is sent to the reactor pressure vessel 109 by the reactor containment vessel spray system pump 112. It is dispersed into the upper dry well 106 to cool the inside of the reactor containment vessel. In this case, the pool water A sprayed in the upper dry well 106 accumulates on the diaphragm floor 105, but the communication passage 11
A partition wall 114 is provided around the opening of 3...,
Since the upper end openings of these communication passages 113 are located substantially higher than the upper ends of the vent pipes 107,
The pool water A accumulated on the diaphragm floor 105 is returned to the suppression chamber 104 through these vent pipes 107 and then flows into the lower dry well 103.
There will be no inflow into the country. Therefore, important equipment such as the control rod drive mechanism 110 housed in the lower dry well 103 will not be submerged in water.
Its soundness is maintained.

Further, since all of the sprayed pool water A is returned to the suppression chamber 104 and contributes to steam condensation, the amount of pool water A in the suppression chamber 104 can be smaller than conventionally. Note that the first invention is not limited to the above embodiments.

Next, the second invention will be explained with reference to FIGS. 4 to 7. FIG. 4 shows a first embodiment of the second invention, and in this first embodiment, a communication path 1 that communicates an upper dry well 106 and a lower dry well.
The upper end opening of the vent pipe 107 is set at a higher position than the upper end opening of the vent pipe 107, and an upper partition wall 115 is provided on the outer periphery of the pedestal 108 to cover the upper end opening of the communication path 113 and serve as a means for preventing intrusion of falling water.
is provided to protrude in the horizontal direction.

Therefore, in this embodiment, the upper end opening of the communication passage 113 is set at a higher position than the upper end opening of the vent pipe 107, so that the upper dry well 1
06 and accumulated in the diaphragm floor 105 can be prevented from flowing into the lower dry well 103 from the upper end opening of the communication passage 113, and the upper end opening of the partition wall 114 is covered on the outer periphery of the pedestal 108. Since the upper partition wall 115 is provided to protrude in the horizontal direction, water falling from above the dry well can be prevented from entering the communication path 113.

Note that the second invention is not limited to the first embodiment described above. For example, when a pipe 116 or the like is passed through a partition wall 114 or an upper partition wall 115 as shown in FIG. 5, a gasket 117 or a liquid flow prevention mechanism 118 is provided at the penetration part to prevent inflow from the penetration part. Can be done.

In addition, as shown in FIG.
Since the upper end opening of No. 3 faces downward, the intrusion of falling water can be further prevented.

Furthermore, as shown in FIG. 7, a check valve mechanism 119 that only allows flow from the lower dry well 103 to the upper dry well 106 may be provided at the upper end opening of the communication passage 113.

As mentioned above, the first invention includes an upper dry well formed surrounding the upper part of the reactor pressure vessel, a lower dry well formed surrounding the lower part of the upper reactor pressure vessel, and the lower dry well. A suppression chamber provided around the upper drywell and a vent pipe inserted into the suppression chamber by penetrating the diaphragm floor at the bottom of the upper drywell communicate with the upper drywell and the lower drywell. and a communication passage whose upper end opens at a position higher than the upper end of the vent pipe.

Therefore, according to the first aspect of the present invention, since the upper end opening of the communication passage is set at a higher position than the upper end opening of the vent pipe, it is possible to prevent the spray from being sprayed in the upper dry well and accumulating on the diaphragm floor. Water can be prevented from flowing into the lower dry well from the upper end opening of the communication path.

Further, the second invention provides an upper dry well formed surrounding the upper part of the reactor pressure vessel, a lower dry well formed surrounding the lower part of the reactor pressure vessel, and a surrounding area of the lower dry well. a suppression chamber provided, a vent pipe inserted into the suppression chamber by penetrating the diaphragm floor at the bottom of the upper drywell, and the upper drywell and the lower drywell. In a reactor containment vessel having a communication passage, the upper end opening of the communication passage is set at a higher position than the upper end opening of the vent pipe, and the intrusion of falling water above the communication passage is prevented. It is equipped with means to prevent falling water from entering. Therefore, according to the second aspect of the present invention, it is possible to prevent water that has been scattered in the upper dry well and accumulated on the diaphragm floor from flowing into the lower dry well from the upper end opening of the communication passage, and also to prevent water from flowing into the lower dry well. Water falling from above can be prevented from entering the communication path, and the capacity of the suppression chamber can be reduced.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a conventional example. 2 and 3 show an embodiment of the first invention, in which FIG. 2 is a vertical cross-sectional view of the entire reactor containment vessel, FIG. 3 is a vertical cross-sectional view of the upper part of the communication passage, and FIG. 7 to 7 show a second embodiment of the present invention, FIG. 4 is a longitudinal sectional view showing the first embodiment, FIG. 5 is a longitudinal sectional view showing the second embodiment, and FIG. 6 is a longitudinal sectional view showing the third embodiment. Longitudinal cross-sectional view showing the embodiment, No. 7
The figure is a longitudinal sectional view showing the fourth embodiment. 101... Containment vessel main body, 102... Partition wall, 1
03... lower dry well, 104... suppression chamber, 105... diaphragm floor, 107... vent pipe, 109... reactor pressure vessel, 114... partition wall, 115... upper partition wall,
119...Check valve mechanism.

Claims (1)

[Scope of Claims] 1. An upper dry well formed surrounding the upper part of the reactor pressure vessel, a lower dry well formed surrounding the lower part of the reactor pressure vessel, and a lower dry well provided around the lower dry well. The suppression chamber is connected to the vent pipe inserted into the suppression chamber by penetrating the diaphragm floor at the bottom of the upper drywell, and the upper drywell and the lower drywell are connected so that the upper end thereof is connected to the suppression chamber. A nuclear reactor containment vessel characterized by comprising a communicating passage opened at a position higher than the upper end of the vent pipe. 2. An upper dry well formed surrounding the upper part of the reactor pressure vessel, a lower dry well formed surrounding the lower part of the reactor pressure vessel, and a suppression channel provided around the lower dry well. a vent pipe inserted into the suppression chamber by penetrating the diaphragm floor at the bottom of the upper drywell, and a communication passage formed between the upper drywell and the lower drywell. In the reactor containment vessel, the upper end opening of the communicating passage is set at a higher position than the upper opening of the vent pipe, and falling water intrusion prevention means for preventing falling water from entering is provided above the communicating passage. A nuclear reactor containment vessel characterized by: