JP4436797B2 - Reactor facility - Google Patents

Description

  The present invention relates to a nuclear reactor facility composed of a nuclear reactor building and a reactor containment vessel of a boiling water reactor disposed in the reactor building, and in particular, to the configuration of the reactor containment vessel and to this It relates to the arrangement of various equipment, piping, and spent fuel storage pool.

  As types of conventional containment vessels of boiling water reactors (hereinafter referred to as BWR), Mark I type, Mark II type and the latest improved BWR (hereinafter referred to as ABWR) are known. The Mark I reactor containment vessel is called a torus type, and is constituted by a donut (torus) -shaped suppression chamber having a bell-shaped dry well for containing a reactor pressure vessel and the like and a suppression pool. In addition, there is a modification of the mark I type storage container in which the suppression chamber is a vertical tank, such as a dodeward plant. In addition, Mark II and ABWR are slightly different in shape depending on whether they are made of steel or reinforced concrete, but basically there is a dry well that houses the reactor pressure vessel and a suppression chamber that houses the suppression pool. The reactor containment vessel has a configuration / shape arranged vertically (see, for example, Non-Patent Document 1).

These reactor containment vessels are safety-related facilities and are required to have high pressure resistance / leakage resistance and seismic resistance, so that the economy can be improved by downsizing. In addition, since the containment vessel must be surrounded by a secondary containment facility, the downsizing of the containment vessel contributes to the downsizing of the reactor building. Furthermore, since the reactor containment vessel constitutes a critical path for the reactor building construction process, it is possible to shorten the construction period of the building by shortening the construction process of the reactor containment vessel. From such a background, various studies have been made as measures for reducing the size of the reactor containment vessel and shortening the construction process (see, for example, Patent Document 1 and Patent Document 2 for measures for shortening the construction period).
Hitachi Review Vol. 68 no. 4 (1986-4) JP 7-35887 A Japanese Patent Laying-Open No. 2003-167086

  In order to realize a more economical reactor facility, it is effective to provide a reactor containment vessel that is downsized and contributes to shortening of the construction process. In the reactor containment vessels in Mark I, Mark II, and ABWR, first, the reactor pressure vessel is centered, and the main steam piping, feed water piping, and reactor water injection piping route connected to the reactor pressure vessel around An air conditioner that secures the space required for disassembly and inspection of facilities that require disassembly and inspection, such as safety relief valves, main steam isolation valves (reactor isolation valves), and keeps the atmosphere inside the reactor containment vessel constant The shape and dimensions of the dry well are determined after securing the installation space. On the other hand, a suppression chamber with a suppression pool that guides and condenses high-temperature and high-pressure steam generated in the dry well is a donut-shaped area around the bottom of the dry well (mark I type) In the case of the Mark II type and the ABWR type, the tank is installed at the lower part of the dry well and is connected by a vent pipe for guiding the vapor of the respective dryware to the suppression chamber.

  As described above, the conventional reactor containment vessel has a dry well in the upper part and a suppression chamber in the lower part. In the construction sequence, the basic procedure is followed to construct the dry well after constructing the suppression chamber. It becomes. Further, in terms of dimensions, the related equipment starting from the main steam pipe and the water supply pipe is integrated with the reactor pressure vessel. In addition, as described above, the reactor containment vessel is required to have high pressure resistance, and its shape is limited to shapes such as a spherical shape, a cylindrical shape, and a torus shape. There is a limit to the size reduction.

  An object of the present invention is to provide a configuration of a reactor containment vessel that enables downsizing of the reactor containment vessel and shortening of a construction process in a boiling water nuclear power plant.

  In order to achieve the above object, the present invention is characterized by having the configurations shown in the following (1) to (4).

(1) The reactor containment vessel is divided and installed.

(2) A plurality of divided reactor containment vessels are installed in parallel, and each reactor containment vessel is connected by a connecting pipe.

(3) Install necessary piping such as main steam piping and water supply piping in the connecting pipe.

(4) Centrally install equipment and facilities that require maintenance and inspection, such as safety relief valves and main steam isolation valves, in one reactor containment vessel.

  Specifically, the first means of the present invention is a nuclear reactor facility comprising a nuclear reactor building and a nuclear reactor containment vessel disposed in the nuclear reactor building, wherein the nuclear reactor containment vessel is The reactor pressure vessel containing the reactor core, and the necessary piping and air conditioner including the main steam pipe connected to the reactor pressure vessel and having a relief safety valve and a main steam isolation valve are arranged on the path. A dry well, a suppression chamber having a suppression pool inside the dry well and a diaphragm floor, and a vent pipe for guiding the pressure of the dry well to the suppression pool. A reactor containment vessel, a first reactor containment vessel containing the reactor pressure vessel, the relief safety valve, the main steam isolation valve, the air conditioner, the diaphragm The main reactor is divided into a second reactor containment vessel provided with a floor, the suppression chamber and the vent pipe, and the first and second reactor containment vessels are connected via a connecting pipe, and the main steam is contained in the connecting pipe. It is characterized by laying necessary piping including piping.

  According to a second means of the present invention, in the nuclear reactor facility described in the first means, the second reactor containment vessel is composed of a main body portion and a lid portion detachably attached to the main body portion. It is characterized by that.

  According to a third means of the present invention, in the nuclear reactor facility according to the first means, the connecting pipe is separated from the connecting pipe at an upper part of the reactor core between the first and second reactor containment vessels. A second connecting pipe is installed, and a connecting pipe having one end connected to the first reactor containment vessel and the other end connected to the vent pipe is laid in the second connecting pipe.

  According to a fourth means of the present invention, in the nuclear reactor facility according to the first means, a spent fuel storage pool is installed in an upper part of the second reactor containment vessel in the reactor building. To do.

  The fifth means of the present invention is characterized in that, in the nuclear reactor facility described in the first means, a safety system pump is installed in a lower part of the second reactor containment vessel in the reactor building.

  According to the present invention, since the reactor containment vessel is divided and installed in parallel, the reactor pressure vessel can be reduced in size and the construction period of the reactor building can be shortened. Can be improved. In addition, because the reactor pressure vessel can be downsized, safety such as earthquake resistance can be improved, and the reactor containment vessel has been divided, so that by concentrating and installing equipment that requires disassembly and inspection on one side In addition, it can be expected to reduce the exposure when the inside of the containment vessel is inspected.

  Examples of the nuclear reactor facility according to the present invention will be described below.

  1 is a longitudinal sectional view of an essential part of a nuclear reactor facility according to a first embodiment, FIG. 2 is a plan view of an essential part of the nuclear reactor facility according to the first embodiment, and FIG. 3 is a reactor building of the nuclear reactor facility according to the first embodiment. FIG.

  As shown in FIGS. 1 and 2, the reactor facility of this example is configured by installing a reactor pressure vessel 2 containing a reactor core 1 in a first reactor containment vessel 4. The reactor pressure vessel 2 is supported on the base plate 6 of the reactor building 25 by the reactor pedestal 3 that forms part of the first reactor containment vessel 4. On the other hand, the second reactor containment vessel 5 is provided with a suppression chamber 9 having suppression pool water 8 in the lower part, and a main steam pipe 12 provided on the path with a relief safety valve 13 and a main steam isolation valve 14 in the upper part. A dry well 9a having a monorail 15 and an air conditioner 16 for disassembling and inspecting the relief safety valve 13 and the main steam isolation valve 14 is installed, and at the boundary between the suppression chamber 9 and the dry well 9a, a diaphragm floor 10 and A vent pipe 11 is installed.

  The second reactor containment vessel 5 is installed on the turbine building side of the first reactor containment vessel 4 (the right side in FIGS. 1 and 2), so that the route and length of the main steam pipe 12 are rational. It is supposed to be.

  In addition, the first reactor containment vessel 4 and the second reactor containment vessel 5 are connected by a connecting pipe 7, and in the connecting pipe 7, there are provided necessary piping such as a main steam pipe 12 and a water supply pipe (not shown), a second pipe. A ventilation duct or the like from the air conditioner 16 installed in the reactor containment vessel 5 is installed.

  As shown in FIG. 2, in the second reactor containment vessel 5, a main steam pipe 12 provided with a relief safety valve 13 and a main steam isolation valve 14 on its path is installed, and an air conditioner 16 is provided in the vicinity thereof. is set up. Thus, in the nuclear reactor facility of this example, the devices that require maintenance and inspection are concentrated and installed in the second reactor containment vessel 5. As a result, it is possible to efficiently install the facilities conventionally installed around the reactor pressure vessel in the second reactor containment vessel 5.

  In addition, as shown in FIG. 3, in the reactor facility of this example, a safety system pump 17 that uses the suppression pool in the second reactor containment vessel 5 as a water source is installed in the vicinity of the second reactor containment vessel 5. The spent fuel storage pool 18 is installed adjacent to the first reactor containment vessel 4 and on the opposite side of the turbine building.

  The high-temperature and high-pressure steam generated in the first reactor containment vessel 4 is condensed after being led to the suppression pool water 8 via the vent pipe 11 in the second reactor containment vessel 5 and stored in the reactor. Although the pressure in the vessel is reduced, the connecting pipe 7 also has a role of guiding high-temperature and high-pressure steam generated in the first reactor containment vessel 4 into the second reactor containment vessel 5. At this time, it is possible to easily cope with the problem by increasing the inner diameter of the connecting pipe 7 or installing a plurality of the connecting pipes 7 so that an excessive pressure is not partially generated in the first reactor containment vessel 4. .

  In addition, during the periodic inspection of the reactor, fuel replacement work and the safety valve 13 and the reactor isolation valve 14 are disassembled and inspected. In a conventional containment vessel, these components are disassembled / removed around the reactor pressure vessel. Since equipment requiring inspection was installed, a shielding wall was installed around the reactor pressure vessel to reduce exposure from the reactor core, but the reactor facility in this example was disassembled from the reactor pressure vessel. -Since equipment that requires inspection is installed in a separate space, it can contribute to reducing exposure during periodic inspections.

  As described above, since the reactor facility of this example has a split structure of the reactor containment vessel, the inner diameter of the reactor containment vessel whose shape and size have been determined in the past can be made smaller. Therefore, the reactor containment vessel can be made more compact and can withstand higher pressure. That is, in the reactor containment vessel, the ratio of the spatial volume of the suppression chamber 9 to the other spatial volume partitioned by the diaphragm floor 10 (the spatial volume of the suppression chamber 9 / the other spatial volume partitioned by the diaphragm floor 10). The design pressure of the containment vessel is determined by (for example, about 0.8 in ABWR). However, if the design pressure is large, the volume ratio can be reduced. This reduces the spatial volume of the suppression chamber 9. It means that it is possible.

  In addition, regarding the relationship between the design pressure and the inner diameter of the containment vessel, the thickness (t) necessary for the cylinder calculation is fixed as shown in the following “calculation formula of the cylindrical cylinder receiving pressure on the inner surface”. In this case, if the inner diameter (Di) of the cylinder is small, the maximum operating pressure (P) can be increased, and the space volume of the compact reactor containment vessel, that is, the suppression chamber 9 can be reduced.

"Calculation formula of cylindrical body under pressure on inner surface"
t = PDi / (200Sη−1.2P)
Where t is the thickness required for the calculation of the trunk
P: Maximum operating pressure
Di: inner diameter of the trunk
S: Allowable tensile stress of material
η: Joint efficiency As shown in FIG. 1, the reactor facility of the present example installs the first reactor containment vessel 4 and the second reactor containment vessel 5 in parallel. Instead of the method of constructing the reactor building 25 in order from the bottom as in the case of the vessel, it is possible to adopt a method of constructing the reactor pressure vessel 2 and other parts in parallel. As a result, the construction process of the reactor containment vessels 4 and 5 can be shortened, and secondarily, improvement in earthquake resistance can be expected by lowering the center of gravity of the entire containment vessel.

  Furthermore, since the reactor facility of this example is easy to modularize the reactor containment vessel, the first reactor containment vessel 4 includes the reactor pressure vessel 2 and the main body of the first reactor containment vessel 4, the second Concerning the reactor containment vessel 5, facilities other than those installed in the first reactor containment vessel 4 are integrally incorporated in the building periphery yard or a dedicated module factory, and the modularized reactor containment vessels 4 and 5 are large-sized. The crane can be installed in the reactor building.

  FIG. 4 is a diagram illustrating the construction procedure of the reactor facility according to the first embodiment for each construction sequence. In the construction sequence 1 of FIG. 4, the reactor building 25 in which the connecting pipe 7 is embedded at a required position is constructed. In the construction sequence 2, the first reactor containment vessel 4 in which the reactor pressure vessel 2 is already incorporated and the reactor pedestal 3 that supports the reactor pressure vessel 2 is integrally formed and modularized is formed in the reactor building 25. Then, the suppression chamber 9 is installed at the lower part, and the main steam pipe 12 having the relief safety valve 13 and the reactor isolation valve 14 provided on the upper part thereof, the relief safety valve 13 and the reactor isolation valve. A dry well 9a having a monorail 15 for disassembling and inspecting 14 is installed, and a diaphragm floor 10 and a vent pipe 12 are preliminarily incorporated at the boundary between the suppression chamber 9 and the dry well 9a to be modularized. The second reactor containment vessel 5 is incorporated into a predetermined part of the reactor building 25. In the construction sequence 3, the first reactor containment vessel 4 and the connecting pipe 7 are connected by welding, and the second reactor containment vessel 5 and the connecting pipe 7 are connected. Thereafter, in the construction sequence 4, in the case of a concrete diaphragm floor, concrete is placed on the diaphragm floor 10, and the suppression pool water 8 is injected into the suppression chamber 9. In addition, although support for supporting piping is installed in piping, such as the main steam piping 12, this support is effectively utilized also as fixed equipment at the time of module incorporation.

  In this way, the reactor facility of this example can parallelize the procedures that have been constructed from the lower part of the conventional reactor containment vessel sequentially upward, so that the first and second reactor containment vessels can be installed in parallel. Combined with the modularity, the construction period can be shortened and the labor saving of the local construction can be achieved.

  FIG. 5 is a longitudinal sectional view of a main part of the nuclear reactor facility according to the second embodiment, and FIG. 6 is a plan view of the nuclear reactor facility according to the second embodiment. The reactor facility of this example has a configuration in which a spent fuel storage pool 18 is installed above the second reactor containment vessel 5, that is, on the turbine building side of the first reactor containment vessel 4.

  Since the position of the second reactor containment vessel 5 in the vertical direction can be adjusted separately from the position of the first reactor containment vessel 4 by changing the length of the main steam pipe 12, the basics of the present invention. The vertical position of the second reactor containment vessel 5 can be easily adjusted without changing the configuration. And if the 2nd reactor containment vessel 5 and the spent fuel storage pool 18 are installed in the same projection like the reactor facility of this example, since the projected area of the reactor building can be reduced, it is more compact. It becomes possible to provide a simple building. Moreover, since the shielding floor and pool floor of the upper part of the 2nd reactor containment vessel 5 can be used together, it can also contribute to reduction of the amount of concrete.

  FIG. 7 is a longitudinal sectional view of a nuclear reactor facility according to the third embodiment. Also in the reactor facility of this example, the basic configuration of the reactor containment vessels 4 and 5 is the same as that of the reactor facility according to the first embodiment, but in this example, the upper part of the second reactor containment vessel 5 is opened. A structure with a possible flange lid is provided so that the safety relief valve 13 and the main steam isolation valve 14 can be maintained and inspected on the operation floor 24. Further, a shielding plug 20 for shielding during normal operation is installed on the upper part of the second reactor containment vessel 5. At the time of periodic inspection, first, the shielding plug 20 is removed, and the flange lid 19 is temporarily placed on the operation floor 24. Thereafter, the relief safety valve 13 and the main steam isolation valve 14 are repaired or inspected on the operation floor 24. All of the movement and temporary placement of the articles accompanying these operations can be operated with an overhead crane installed on the operation floor 24.

  The reactor facility of this example does not have a space for disassembling and checking the relief safety valve 13 and the main steam isolation valve 14 at the upper part of the second reactor containment vessel 5, so that the reactor containment vessel can be further downsized. It is possible.

  8 and 9 are longitudinal sectional views of a nuclear reactor facility according to the fourth embodiment. As shown in FIG. 8, drawdown water 21 stays in the lower portion of the first reactor containment vessel 4 because water that uses the suppression pool as a water source is poured into the reactor core in the case of an assumed accident. This drawdown water 21 is designed in advance as a necessary volume added to the suppression pool water 8 as dead water. That is, when the amount of the drawdown water 21 is large, the required amount of the suppression pool water 8 is large, so that the necessary volume of the storage container is increased as a whole. In FIG. 9, in order to reduce the drawdown water 21, the first reactor containment vessel 4 and the second reactor containment vessel 5 are connected by a connecting pipe 7 a that is separate from the connecting pipe 7. The connection pipe 22 is connected to the vent pipe 11 in the second reactor containment vessel 5 at one end.

  In addition, the connection part with the 2nd reactor containment vessel 5 of the connection pipe 7a is taken as a closed structure. This is because, when a virtual accident is assumed in the first reactor containment vessel 4, the high temperature and high pressure steam generated in the first reactor containment vessel 4 is directly condensed without being condensed in the suppression pool water 8. This is to avoid being led to 9. As a result, the drawdown water in the first reactor containment vessel 4 returns to the suppression pool 8 via the communication pipe 22 and the vent pipe 11 in the second reactor containment vessel 5, so that the drawdown water can be reduced. This contributes to the compactness of the entire reactor containment vessel.

  FIG. 10 is a longitudinal sectional view of a main part of a nuclear reactor facility according to the fifth embodiment, and FIG. 11 is a plan view of the nuclear reactor facility according to the fifth embodiment.

  As shown in the second embodiment, the vertical position of the second reactor containment vessel 5 can be adjusted by the length of the main steam pipe 12 separately from the position of the first reactor containment vessel 4. In this example, as shown in FIG. 10, a safety system pump 17 is installed at the lower part of the second reactor containment vessel 5, the suppression pool water 8 is guided directly to the pump, and the first reactor is supplied by the water injection system pipe 23. Water is poured into the reactor pressure vessel 2 in the containment vessel 4. Furthermore, since the safety pump 17 is installed below the suppression pool water 8, it is possible to secure a sufficient suction head, and as a result, it is possible to employ a horizontal pump that allows maintenance and inspection within the same floor. Moreover, since the safety system pump 17 is installed in the lower part of the suppression pool water 8, as shown in FIG. 11, when the 2nd reactor containment vessel 5 and the safety system pump 17 are installed in the same projection plane, The floor area of the building is reduced, and a compact reactor building can be provided. It is also possible to modularize the safety pump 17 and the second reactor containment vessel 5 up and down to further improve the workability.

1 is a longitudinal sectional view of a main part of a nuclear reactor facility according to Embodiment 1. FIG. 1 is a cross-sectional view of a main part of a nuclear reactor facility according to a first embodiment. 1 is a plan view of a nuclear reactor facility according to Embodiment 1. FIG. It is a figure which shows the construction sequence of the nuclear reactor facility which concerns on Example 1. FIG. 3 is a longitudinal sectional view of a main part of a nuclear reactor facility according to Embodiment 2. FIG. 3 is a plan view of a nuclear reactor facility according to Embodiment 2. FIG. 6 is a longitudinal sectional view of a main part of a nuclear reactor facility according to Embodiment 3. FIG. FIG. 6 is a longitudinal sectional view of a main part of a nuclear reactor facility according to a fourth embodiment. FIG. 6 is a longitudinal sectional view of a main part of a nuclear reactor facility according to a fourth embodiment. 10 is a longitudinal sectional view of a main part of a nuclear reactor facility according to Embodiment 5. FIG. 10 is a plan view of a nuclear reactor facility according to Embodiment 5. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Reactor core 2 Reactor pressure vessel 3 Reactor pedestal 4 1st reactor containment vessel 5 2nd reactor containment vessel 6 Building foundation version 7, 7a Connection pipe 8 Suppression pool 9 Suppression chamber 9a Drywell 10 Diaphragm floor 11 Vent Pipe 12 Main steam piping 13 Relief safety valve 14 Main steam isolation valve 15 Monorail 16 Air conditioner 17 Safety system pump 18 Spent fuel storage pool 19 Second reactor containment vessel lid 20 Shield plug 21 Drawdown water 22 Connection pipe 23 Injection system piping 24 Reactor building operation floor 25 Reactor building

Claims (5)

  A reactor facility composed of a reactor building and a reactor containment vessel disposed in the reactor building, wherein the reactor containment vessel includes a reactor pressure vessel containing a reactor core; and A dry well in which necessary piping and air conditioners including a main steam pipe having a relief safety valve and a main steam isolation valve connected to the reactor pressure vessel are disposed, and the dry well and the diaphragm floor A suppression chamber that is divided and has a suppression pool inside, and a vent pipe that guides the pressure of the dry well to the suppression pool, wherein the reactor containment vessel contains the reactor pressure vessel. 1 reactor containment vessel, the safety relief valve, the main steam isolation valve, the air conditioner, the diaphragm floor, the suppression chain And the second reactor containment vessel provided with the vent pipe, the first and second reactor containment vessels are connected via a connecting pipe, and the main steam pipe is included in the connecting pipe. Reactor facility characterized by the installation of piping.   2. The nuclear reactor facility according to claim 1, wherein the second reactor containment vessel includes a main body portion and a lid portion that is detachably attached to the main body portion.   2. The nuclear reactor facility according to claim 1, wherein a second connection pipe separate from the connection pipe is installed above the nuclear reactor core between the first and second reactor containment vessels, and the second A reactor facility characterized in that a connecting pipe having one end connected to the first reactor containment vessel and the other end connected to the vent pipe is laid in a connecting pipe.   The nuclear reactor facility according to claim 1, wherein a spent fuel storage pool is installed in an upper portion of the second reactor containment vessel in the reactor building.   2. The nuclear reactor facility according to claim 1, wherein a safety pump is installed in a lower portion of the second reactor containment vessel in the nuclear reactor building.

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