JP3731344B2 - Reactor pressure vessel unloading method and unloading switchgear - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an unloading method and unloading switchgear for unloading large equipment such as a reactor pressure vessel housed in a reactor building of a nuclear power plant.
[0002]
[Prior art]
The reactor pressure vessel (hereinafter referred to as RPV) is the most important equipment of a nuclear power plant, and the service period of the nuclear power plant generally depends on the service period of the RPV and ancillary equipment inside and outside the reactor. In recent years, it has become an important issue to extend the life of nuclear power plants and extend the operating period of aged nuclear power plants that are currently in operation. In order to extend the operating period of an aged nuclear power plant, it has become necessary to replace the RPV including the auxiliary equipment inside and outside the reactor.
[0003]
The RPV removal method from the reactor building accompanying the replacement of the RPV includes the first method in which the RPV is shredded in the reactor building, stored in a storage container, and carried out, and the RPV is carried out from the reactor building while being integrated. There is a second method. In order not to increase the capacity of the storage facility, the second method is advantageous.
[0004]
As a conventional technique for carrying out the RPV as one unit, for example, in Japanese Patent Laid-Open No. 8-262190, a frame is provided across the reactor building, and a storage facility equipped with an air lock, a crane, etc. is provided on this frame, A technique for moving the RPV into the storage facility and carrying it out is described. This publication also describes that the release of radioactive material from the reactor building can be prevented by carrying out RPV using this apparatus.
[0005]
[Problems to be solved by the invention]
However, for example, in a reactor with an output of 780 MWe, the RPV has a diameter of about 6 m, a length of about 22 m, and a weight of about 530 tons. Therefore, in the above-described conventional technology, the storage equipment and the frame for storing the RPV are quite large. It will be something. Along with this, the cost also increases.
[0006]
An object of the present invention is to carry out an RPV carrying-out method capable of preventing the release of radioactive substances from a building using a relatively simple facility and using existing building air-conditioning equipment, even when carrying out an RPV integrally from a reactor building. An object of the present invention is to provide an unloading switchgear.
[0007]
[Means for Solving the Problems]
A first invention for achieving the above object is a method for carrying out a reactor pressure vessel in which a reactor pressure vessel housed in a reactor building of a nuclear power plant is integrally carried out of a reactor building. A first step of providing a temporary opening for opening and a door that can be opened and closed on the ceiling of the reactor building, a second step of providing a shielding body that shields radiation around the reactor pressure vessel, and a suspension wire can pass through the door A third step in which the reactor pressure vessel is lifted up to just below the door in a state where the reactor pressure vessel is open, and the reactor pressure is just below the door by opening the door to a size that allows the reactor pressure vessel to pass through. A fourth step of unloading the vessel to the outside, and a fifth step of closing the door immediately after unloading the reactor pressure vessel to the outside of the door.
[0008]
A second invention is a method for carrying out a reactor pressure vessel in which a reactor pressure vessel housed in a reactor building of a nuclear power plant is integrally carried out of the reactor building, and is carried out to the ceiling of the reactor building. The first step of providing a temporary opening and a door that can be opened and closed, the second step of providing a shield for shielding radiation around the sub reactor pressure vessel, and storing the reactor pressure vessel inside the temporary opening A third step of providing a seal curtain for the fourth step, a fourth step of opening the door after the reactor pressure vessel is housed in the seal curtain, and carrying the reactor pressure vessel to the outside, and the reactor pressure vessel And a fifth step of closing the door after unloading to the outside of the door.
[0009]
A third invention relates to a method for carrying out a reactor pressure vessel in which a reactor pressure vessel housed in a reactor building of a nuclear power plant is integrally carried out of the reactor building, and is carried out to the ceiling of the reactor building. A first step of providing a temporary opening and a door that can be opened and closed, a second step of providing a shield for shielding radiation around the reactor pressure vessel, and the temporary opening and the lower side of the temporary opening. A third step of forming an air curtain for separating the interior of the reactor building, a fourth step of opening the door and carrying out the reactor pressure vessel to the outside, and carrying out the reactor pressure vessel to the outside of the door And a fifth step of closing the door later.
[0010]
A fourth invention is an unloading switchgear used for unloading a reactor pressure vessel from a reactor building of a nuclear power plant, formed on the ceiling of the reactor building, for shielding radiation around it A temporary opening for passing a reactor pressure vessel provided with a shield, and a door provided at an upper portion of the temporary opening, the doors being in directions opposite to each other with respect to the central axis of the temporary opening; The upper door and the lower door each have a semicircular cutout on the central axis side of the temporary opening, A sealing member is provided in the notch.
[0011]
A fifth invention is an unloading switchgear used for unloading a reactor pressure vessel from a reactor building of a nuclear power plant, and is formed on the ceiling of the reactor building for shielding radiation around it. A temporary opening for passing a reactor pressure vessel provided with a shield, a door provided at an upper portion of the temporary opening and capable of opening and closing, and a shield provided inside the temporary opening are provided. And a sealing curtain for accommodating the reactor pressure vessel therein.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
A first embodiment of a method for carrying out a reactor pressure vessel (RPV) according to the present invention to the outside of a reactor building will be described below with reference to FIGS. FIG. 1 is a flowchart showing the unloading procedure of the first embodiment, FIG. 2 is a schematic longitudinal sectional view of a reactor building to which the unloading method of the present embodiment is applied, and FIG. 3 is a reactor containment vessel (hereinafter referred to as PCV) of FIG. FIG. 4 to FIG. 16 are schematic longitudinal sectional views showing the state around the PCV in the main work steps of FIG. The present embodiment shows a procedure from carrying out the RPV integrally from the reactor building to transporting it to the temporary storage facility.
[0013]
As shown in FIG. 2, there is a PCV 3 in the reactor building 4 and an RPV 1 is accommodated. An in-furnace structure 2 is accommodated in the RPV 1. In the upper region of the reactor building 4, a reactor well 9 is provided above the PCV 3, and a spent fuel pool 19 is provided adjacent to the reactor well 9. The reactor well 9 is filled with water when the fuel is changed or when the reactor internal structure 2 is taken out.
[0014]
As shown in FIG. 3, the RPV 1 is fixed to the RPV pedestal 5 serving as a foundation with an RPV foundation bolt 6. An RPV heat insulating material 7 and a γ-ray shield (hereinafter referred to as RSW) 8 that shields radiation are provided on the outer periphery of the RPV 1. A fuel exchange bellows 10 and a bulkhead plate 11 for partitioning the reactor well 9 and the PCV 3 are provided on the upper part of the PCV 3.
[0015]
The RPV 1 is provided with a main steam nozzle 12, a feed water nozzle 13, a recirculation inlet nozzle 14, a recirculation outlet nozzle 15, etc., and a main steam pipe 22, a feed water pipe 23, a recirculation inlet pipe 24, and a recirculation outlet pipe. 25 is connected to each system piping. At the top of the RPV 1 is a reactor pressure vessel lid (hereinafter referred to as RPV top head) 16, and at the bottom of the RPV 1 is a CRD housing 17 for storing a control rod drive (hereinafter referred to as CRD) and a neutron flux detector ( Hereinafter, an ICM housing 18 for housing the ICM) is provided.
[0016]
First, in step S1 of FIG. 1, the generator is disconnected and the operation of the nuclear power plant is stopped. In step S2, the RPV top head 16 is opened and the reactor opening operation is performed. In the nuclear reactor opening operation, an operation of removing the RPV top head 16 and an operation of taking out a part of the reactor internal structure 2 are performed. In step S3, all fuel is taken out from the core and moved to the spent fuel pool 19 in the reactor building 4.
[0017]
FIG. 4 shows a state around the PCV during the fuel extraction operation in step S3. When the RPV 1 and the reactor internal structure 2 are carried out, since the fuel 20 is a radiation source, if the RPV 1 and the reactor internal structure 2 are carried out outside the reactor building with the fuel 20 loaded, the radioactive contamination in the atmosphere There is a possibility. Therefore, in order to reduce the surface dose of the RPV 1, an operation for taking out all the fuel 20 from the core is performed.
[0018]
Next, in step S4, the work of cutting the nozzles and pipes of the RPV 1 and the work of removing the RPV foundation bolt 6 and separating the RPV 1 from the RPV pedestal 5 are performed to disassemble the RPV. In FIG. 5, positions where the pipes connected to the nozzles of the bulkhead plate 11 of the PCV3, the PCV stabilizer 21 and the RPV1 are removed are indicated by broken lines. In FIG. 5, PCV stabilizer 21 is an earthquake-resistant support that connects PCV 3 and RSW 8, and 26 is a plug for preventing leakage of reactor water when pipes 22 to 25 are cut.
[0019]
In this step, first, the bulkhead plate 11 is cut and removed, and then the PCV stabilizer 21 is cut and removed to secure a space for carrying out the removed items in the PCV 3. Next, the plug 26 is attached to the RPV nozzles 12 to 15, the RPV nozzles 12 to 15 and the pipes 22 to 25 are cut and removed, and the disassembly around the RPV is completed.
[0020]
At this time, in step S5, in parallel with the operation of step S4, a large lifting machine 29 used to carry out the RPV 1 from the reactor building 4 is installed in the vicinity of the reactor building 4. FIG. 6 is a view showing a state in which a large lifting machine 29 is installed in the vicinity of the reactor building 4. Next, in Step S <b> 6, a temporary opening and a door for carrying out RPV are provided on the ceiling of the reactor building 4. FIG. 7 shows a state in which a temporary opening 31 for carrying out RPV is provided on the ceiling of the reactor building 4 and a door 32 that can be opened and closed is provided on the roof. The door 32 is an upper door that can slide (open and close) in directions opposite to each other with respect to the central axis of the temporary opening 31 having a circular cross section.
32a and a lower door 32b. FIG. 8 shows a state in which the suspension hook 29 a of the large lifting machine 29 is positioned directly above the door 32.
[0021]
Next, in step S <b> 7, the door 32 on the upper side of the temporary opening 31 is opened by a space that can carry the hanging hook 29 a of the large lifting machine 29. In step S8, the hanging hook 29a of the large hoist is carried in. FIG. 9 shows a state in which a part of the door 32 is opened and the hanging hook 29a of the large lifting machine 29 is carried into the reactor building.
[0022]
Hereinafter, a state in which the door 32 in which the upper door 32a and the lower door 32b are vertically doubled will be described with reference to FIG. When the door 32 is closed, as shown in FIG. 10A, the upper door 32a and the lower door 32b are completely overlapped. The door 32 has a structure in which the upper door 32 a and the lower door 32 b slide (open and close) simultaneously in opposite directions with respect to the central axis of the temporary opening 31. A state in which a part of the door 32 is opened is shown in FIG. The upper door 32a and the lower door 32b have a cutout portion with a semicircular cross section on the central axis side of the temporary opening portion 31. A seal member 32c such as rubber or a sheet is attached to the cutout portions of the upper door 32a and the lower door 32b. The fully open state of the door 32 is shown in FIG.
[0023]
Here, the standard of the opening area of the temporary opening part 31 is demonstrated. In order to manage the negative pressure inside the building with the existing ventilation (air conditioning) equipment installed in the reactor building, the amount of air outflow from the temporary opening 31 of the reactor building 4 and the existing ventilation equipment It is necessary to compare the capacity and determine the opening area of the temporary opening 31 that is allowed at the time of carrying out the RPV.
[0024]
Ventilation power P due to wind outside the building₁(kgf / m²) Is generally given by:
[0025]
[Expression 1]
P₁= C ・ γ ・ v₁ ²/ 2g (Equation 1)
Where C is the wind pressure coefficient, γ (kgf / m^Three) Is the specific weight of outside air, v₁(m / s) is the wind speed over the building, g = 9.8 (m / s²) Is the acceleration of gravity. On the roof of the building, C = -0.9. Here, the negative wind pressure coefficient means a suction force from indoors to the outdoors.
[0026]
On the other hand, the outflow amount P per unit opening area of indoor air due to the generated differential pressure P₀(kgf / m²) Is generally given by:
[0027]
[Expression 2]
P₀= Γ ・ ζ₀・ V₀ ²/ 2g (Equation 2)
Where ζ₀Is the outflow loss coefficient of the opening, v₀(m / s) is the outflow air flow velocity at the opening.
[0028]
Ζ now₀Try to estimate. For the sake of simplicity, consider a model in which air in a pipe flows out into the atmosphere from an orifice provided at the outlet of the pipe. In this case, the pipe inner diameter d and the orifice diameter d₀Ratio d₀/ D and the outflow loss coefficient ζ when air exits the orifice₀There is a relationship as shown in FIG. Therefore, for example, the average inner diameter of the reactor building corresponding to the pipe inner diameter d is 40 m, the orifice diameter d₀When the inner diameter of the temporary opening corresponding to is 10 m, d₀/D=0.25, and from FIG.₀= 2.7. Since the inner diameter of the temporary opening is smaller than 10 m, from FIG.₀It can be seen that = 2.7 is maintained.
[0029]
On the other hand, the following equation is obtained from Equation 2.
[0030]
[Equation 3]
v₀= (2g · P₀/ (Γ · ζ₀))^0.5 (Equation 3)
Now P₁(Ventilation force by wind outside the building) and P₀(Air outflow due to generated differential pressure) balanced (P₁= P₀), The following equation is obtained from Equation 1 and Equation 3.
[0031]
[Expression 4]
v₀= V₁(C / ζ₀)^0.5 ... (Equation 4)
Air outflow Q per unit area from the opening₀(m^Three/ H / m²) And v₀Between and Q₀= 3600v₀Therefore, the following equation is obtained from Equation 4.
[0032]
[Equation 5]
Q₀= 3600v₁(C / ζ₀)^0.5 ... (Formula 5)
Usually, a large lifting machine is used under conditions of outdoor wind speed of 10 m / s or less. Therefore, the necessary intake air volume Q required to maintain the reactor building at a negative pressure even under conditions of an outdoor wind speed of 10 m / s.₁Is given by the following equation from Equation 5.
[0033]
[Formula 6]
Q₁= 3600 × 10 × (0.9 / 2.7)^0.5= 20785 (m^Three/ H / m²) ... (Equation 6)
By the way, the ventilation air volume Q on the operating floor of the reactor building in a nuclear power plant with an output of 780 MWe scale₂Is approximately 51000 (m^Three/ H). Therefore, the allowable opening area S (m²) Is given by:
[0034]
[Expression 7]
S = Q₂/ Q₁= 51000/20785 = 2.5 (Expression 7)
In other words, in order to prevent air containing radioactive materials in the reactor building from flowing out of the building, the opening area of the temporary opening when the RPV is carried out is set to 2.5 m.²The following should be done.
[0035]
The opening area of the temporary opening when carrying out RPV is 2.5m²If the following cannot be achieved, it is necessary to provide temporary intake and exhaust facilities to increase the amount of air taken into the reactor building.
[0036]
For the above reasons, in this embodiment, when the RPV passes through the temporary opening 31, the opening area of the gap between the shield (which will be described later in detail) covering the RPV and the temporary opening 31 is 2.5 m.²The temporary opening 31 is configured as follows. For example, when the outer diameter of the shield covering the RPV is about 10 m, the inner diameter of the temporary opening 31 may be about 10.16 m or less. In addition, since the above estimation is performed under the condition of an outdoor wind speed of 10 m / s, when carrying out RPV transportation under a condition where the outdoor wind speed is weaker, the opening area of the gap is set to 2.5 m.²It is allowed to be larger.
[0037]
As described above, the opening area of the gap between the shield covering the RPV and the temporary opening 31 is 2.5 m.²In the following, as shown in FIG. 10 (c), when the RPV is carried out from the temporary opening 31 by providing the sealing member 32c in the cutout portions of the upper door 32a and the lower door 32b, the RPV Since the gap between the shield covering the upper door 32a and the lower door 32b can be made sufficiently small, the building interior can be maintained at a negative pressure even with the existing air conditioning equipment in the reactor building. Thereby, the outflow of the air containing the radioactive substance in the reactor building to the outdoor part of the building can be prevented.
[0038]
Next, a shield is attached to RPV1 with high radioactivity at step S9. In this step, as shown in FIG. 11, first, before lifting the RPV 1, the shield 27 is temporarily placed on the upper side of the RSW 8, the suspension balance 33 is attached to the RPV 1, and the suspension hook 29 a of the large hoist 29 is attached to the suspension balance 33. Install. Thereafter, the RPV 1 is lifted together with the suspension balance 33, and the shield 27 is attached to the lower end portion of the suspension balance 33. In this way, the RPV 1 can be moved with the shield 27 provided on the entire circumference of the RPV 1.
[0039]
Next, in Step S10, the RPV 1 is lifted using the large lifting machine 29. FIG. 12 shows a state where the RPV 1 is lifted. In the figure, the RPV 1 and the shield 27 are lifted by a hanging hook 29 a via a lifting balance 33. In step S11, the shield 28 is also provided on the CRD housing and the ICM housing below the RPV 1. FIG. 13 shows a state in which the shield 28 is provided and the RPV 1 is lifted up to near the ceiling of the reactor building 4. In this state, the upper door 32a and the lower door 32b on the roof of the reactor building 4 are opened to the extent that the suspension wire 29b of the large lifting machine 29 can pass through. In this way, air containing radioactive materials in the reactor building is prevented from flowing out of the building.
[0040]
Next, in step S12, the RPV 1 is carried out to the outside of the reactor building while the door 32 is gradually opened in accordance with the lifting of the RPV 1. That is, in this step, when the RPV 1 is lifted and its upper end approaches the door 32, the door 32 is opened, the temporary opening 31 and the door 32 are passed through the RPV 1, and the door 32 is closed immediately after the passage is completed. In this way, the carrying out of the RPV is completed. FIG. 14 shows a state where the RPV 1 passes through the temporary opening 31, and FIG. 15 shows a state where the RPV 1 is carried out of the reactor building.
[0041]
As described above, in this embodiment, the opening area of the gap between the shield 27 and the temporary opening 31 at the time of carrying out the RPV shown in FIG. 14 is 2.5 m.²While trying to be as follows,
Immediately after carrying out the RPV 1 to the outside of the reactor building, the upper door 32a and the lower door 32b are closed, so that the inside of the reactor building 4 is maintained at a negative pressure, and the air containing the radioactive substance in the reactor building 4 is exposed to the outside. To prevent it from leaking.
[0042]
Next, in step S13, RPV1 is loaded on a large trailer previously arranged in the vicinity of the reactor building 4, and the RPV1 is transported to a temporary storage facility. FIG. 16 shows a state before the RPV 1 unloaded from the reactor building 4 is laid down by the RPV transport skid 34 installed on the large trailer 35 from the lifted state by the large lifter 29 and transported to the temporary storage facility. Indicates.
[0043]
As described above, according to the present embodiment, the existing reactor building air conditioner can be provided when the RPV is integrally carried out from the reactor building only by providing a door with a simple structure above the temporary opening. Can be used to maintain a negative pressure in the reactor building. Therefore, it is possible to prevent the air containing radioactive material in the reactor building from flowing out to the outside with relatively simple equipment. As a result, construction costs can be reduced. Moreover, since large-scale intake / exhaust facilities other than the existing air conditioning facilities are not required, this also contributes to cost reduction. Furthermore, since the RPV can be carried out integrally, the RPV replacement work process can be greatly shortened.
In this embodiment, the example in which the shields 27 and 28 are moved on the RPV 1 has been described. However, the RPV shield is reduced by decontaminating the surface dose of the RPV to a level that does not affect the environment. It is also possible to simplify or move without attaching a shield. In this case, it is possible to unload the RPV unloading work or to remotely monitor the work, thereby further reducing the cost.
[0044]
Moreover, although the present Example demonstrated the example which applied the carrying out method of RPV by this invention to the replacement | exchange work of RPV, the double structure door which piled up two doors was used also for decommissioning work. Needless to say, the present invention can be applied to work for unloading and dismantling large equipment such as RPV.
[0045]
Next, a second embodiment of the RPV carry-out method according to the present invention will be described with reference to FIGS. FIG. 17 is a flowchart showing the unloading procedure of the second embodiment, and FIGS. 18 to 20 are schematic longitudinal sectional views showing the state around the RPV in the main work steps of FIG. In this embodiment, a seal curtain is used when carrying out the RPV. Since steps T1 to T11 in FIG. 17 are the same as steps S1 to S11 of the first embodiment, description thereof is omitted here. In the present embodiment, step T12 and subsequent steps are different from the first embodiment.
[0046]
In step T12 of FIG. 17, a cylindrical seal curtain 36a for housing the RPV 1 is attached to the inside of the temporary opening 31. The seal curtain 36a is installed on the inner surface of the temporary opening 31, and the installation portion is tightly covered so that air inside the reactor building does not enter the seal curtain 36a from this installation portion. As the seal curtain, a construction flameproof sheet or a similar material that is difficult to pass air can be used. In step T13, the RPV 1 is lifted up to a position where the RPV 1 enters the seal curtain 36a. FIG. 18 shows a state after step T13.
[0047]
Next, in step T14, the bottom of the seal curtain 36a is closed so that the RPV 1 is accommodated inside the seal curtain 36a. FIG. 19 shows a state after the end of step T14. In the figure, the bottom of the seal curtain is indicated by 36b. By configuring the seal curtain in this way, the air in the reactor building and the air in the seal curtain are blocked.
[0048]
Next, RPV1 is carried out at step T15. In this step, first, the upper door 32a and the lower door 32b of the temporary opening 31 are opened. Thus, even when the door 32 of the temporary opening 31 is fully opened, the air in the reactor building can be prevented from flowing out of the building due to the blocking action of the seal curtain. After the door 32 is fully opened, the RPV 1 is unloaded from the reactor building 4. FIG. 20 shows a state where the RPV 1 is being carried out. After the completion of carrying out the RPV 1, the upper door 32a and the lower door 32b of the temporary opening 31 are closed, and the RPV carrying out operation is finished. Next, in step T16, the transport operation of RPV 1 is performed in the same manner as in step S13 of FIG.
[0049]
Also in the present embodiment, by simply providing a door and a seal curtain with a simple structure in the temporary opening, the reactor building can be kept at a negative pressure and airtight can be maintained using the existing reactor building air-conditioning equipment. Therefore, it is possible to prevent the air inside the reactor building containing the radioactive material from flowing out to the outside with a relatively simple facility. As a result, construction costs can be reduced. Moreover, since large-scale intake / exhaust facilities other than the existing air conditioning facilities are not required, this also contributes to cost reduction. Furthermore, since the RPV can be carried out integrally, the RPV replacement process can be greatly shortened.
[0050]
Next, a third embodiment of the RPV carry-out method according to the present invention will be described with reference to FIG. The present embodiment is an example of carrying out RPV while maintaining a negative pressure in the reactor building by providing an air curtain at the temporary opening. FIG. 21 is a schematic configuration diagram of a reactor building facility for carrying out the carrying-out method of the present embodiment.
[0051]
In FIG. 21, 37 is an intake fan, 38 is a discharge filter, 39 is a discharge duct, 40 is a discharge nozzle, 41 is an exhaust fan, 42 is a suction filter, 43 is a suction duct, and 44 is a suction nozzle. The front end portion of the discharge duct 39 and the front end portion of the suction duct 43 facing each other on the lower side of the temporary opening 31 have an annular shape in cross section. By providing the discharge nozzle 40 at the tip of the discharge duct 39 having an annular cross section and the suction nozzle 44 at the tip of the suction duct 43 having an annular cross section, the temporary opening having a circular cross section is provided. An air curtain corresponding to the shape of the opening is provided below the portion 31.
[0052]
In the present embodiment, before opening the upper door 32 a and the lower door 32 b of the temporary opening 31, the air in the reactor building 4 sucked by the intake fan 37 is discharged through the discharge filter 38 and the discharge duct 39 to the discharge nozzle 40. Are discharged from the suction nozzle 44 by the exhaust fan 41 and exhausted from the exhaust fan 41 into the reactor building 4 through the suction duct 43 and the suction filter 42. Thus, an air curtain is formed below the door 32 of the temporary opening 31. In FIG. 21, the flow of air from the discharge nozzle 40 to the suction nozzle 44 is indicated by arrows.
[0053]
In this embodiment, with the air curtain formed below the door 32 of the temporary opening 31 in this way, the shields 27 and 28 similar to those of the first embodiment are attached to the RPV 1 and then the RPV 1 is carried out. To do. In this case, equipment for forming an air curtain is required as compared with the first and second embodiments, but it is a relatively simple equipment and uses existing reactor building air conditioning equipment. Thus, the inside of the reactor building 4 can be maintained at a negative pressure, and air containing radioactive materials in the reactor building can be prevented from being released to the outside of the building. As a result, construction costs can be reduced. Moreover, since RPV can be carried out integrally, the process of RPV replacement construction can be significantly shortened.
[0054]
As described above, in the first embodiment, the gap between the RPV and the temporary opening is made extremely small, the seal curtain is used in the second embodiment, and the air curtain is used in the third embodiment. Using relatively simple facilities, the RPV can be carried out integrally while maintaining the reactor building at a negative pressure with the existing air conditioning equipment in the reactor building. In addition, although the above example demonstrated the example of carrying out RPV, this invention is applicable also to carrying out the large sized equipment in reactor buildings other than RPV.
[0055]
【The invention's effect】
According to the present invention, when carrying out large-scale equipment such as RPV from the reactor building as a whole, the reactor building is maintained at a negative pressure using the existing reactor building air-conditioning equipment with relatively simple equipment. It is possible to prevent the air containing radioactive material in the reactor building from flowing out. As a result, construction costs can be reduced. In addition, since large-scale equipment can be carried out integrally, the RPV replacement work and decommissioning work processes can be greatly shortened.
[Brief description of the drawings]
FIG. 1 is a flowchart showing a first embodiment of a method for carrying out an RPV according to the present invention.
FIG. 2 is a schematic longitudinal sectional view of a reactor building to which the carrying-out method of the present invention is applied.
3 is a schematic longitudinal sectional view around the PCV in FIG. 2;
FIG. 4 is a diagram showing a state during work in step S3 of FIG.
FIG. 5 is a diagram showing an application target position of the work in step S4 in FIG. 1;
6 is a diagram showing a state at the end of the operation in step S5 in FIG. 1;
FIG. 7 is a diagram showing a state at the end of the operation in step S6 of FIG.
FIG. 8 is a diagram showing a state at the end of the operation in step S6 of FIG.
FIG. 9 is a diagram showing a state during the operation in step S8 of FIG. 1;
FIGS. 10A and 10B are explanatory diagrams of the open / closed state of the door at the temporary opening, where FIG. 10A shows a state in which the door is closed, FIG. 10B shows a state in which a part of the door is open, and FIG. The fully open state is shown respectively.
FIG. 11 is a diagram showing a state during the operation of step S9 in FIG. 1;
FIG. 12 is a diagram showing a state during work in step S10 of FIG.
FIG. 13 is a diagram showing a state at the end of the operation in step S11 of FIG.
FIG. 14 is a diagram showing a state during the operation of step S12 in FIG. 1;
FIG. 15 is a diagram showing a state at the end of the work in step S12 in FIG. 1;
FIG. 16 is a diagram showing a state during work in step S13 of FIG.
FIG. 17 is a flowchart showing a second embodiment of the RPV carrying-out method according to the present invention.
FIG. 18 is a diagram showing a state at the end of the work in step T13 of FIG.
FIG. 19 is a diagram showing a state at the end of the work in step T14 of FIG.
FIG. 20 is a diagram showing a state during work in Step T15 of FIG.
FIG. 21 is a schematic configuration diagram of a reactor building facility for carrying out a third embodiment of the RPV carrying-out method according to the present invention.
FIG. 22 is a relationship diagram of an air outflow loss coefficient and an orifice diameter.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... RPV, 2 ... Reactor structure, 3 ... PCV, 4 ... Reactor building, 8 ... RSW, 9 ... Reactor well, 17 ... CRD housing, 18 ... ICM housing, 19 ... Spent fuel pool, 20 ... Fuel, 26 ... Plug, 27, 28 ... Shield, 29 ... Large lifting machine, 29a ... Hanging hook, 29b ... Hanging wire, 31 ... Temporary opening, 32 ... Door, 32a ... Upper door, 32b ... Lower door, 33 ... Suspension balance, 34 ... Transport skid, 35 ... Large trailer, 36a, 36b ... Seal curtain, 37 ... Intake fan, 38 ... Discharge filter, 39 ... Discharge duct, 40 ... Discharge nozzle, 41 ... Exhaust fan, 42 ... Suction Filter, 43 ... suction duct, 44 ... suction nozzle.

Claims (6)

In the method of carrying out the reactor pressure vessel in which the reactor pressure vessel housed in the reactor building of the nuclear power plant is integrally carried out of the reactor building,
A first step of providing a temporary opening for opening and a door that can be opened and closed on the ceiling of the reactor building, a second step of providing a shielding body that shields radiation around the reactor pressure vessel, and a suspension wire can pass through the door A third step in which the reactor pressure vessel is lifted up to just below the door in a state where the reactor pressure vessel is open, and the reactor pressure is just below the door by opening the door to a size that allows the reactor pressure vessel to pass through. comprising a fifth steps to close the door immediately after the fourth step, and the reactor pressure vessel and carried to the outside of the door unloading the container to the outside,
The door has a double structure consisting of an upper door and a lower door that are slidable in opposite directions with respect to the central axis of the temporary opening,
Each of the upper door and the lower door has a semicircular cutout on the central axis side of the temporary opening, and a seal member is provided in each cutout. Unloading method. 2. The atom according to claim 1, wherein, when the reactor pressure vessel is unloaded, a cross-sectional area of a gap portion between the shield of the reactor pressure vessel and the temporary opening portion is 2.5 m ² or less. How to carry out the furnace pressure vessel. In the method of carrying out the reactor pressure vessel in which the reactor pressure vessel housed in the reactor building of the nuclear power plant is integrally carried out of the reactor building,
A first step of providing a temporary opening for opening and a door that can be opened and closed on the ceiling of the reactor building, a second step of providing a shielding body that shields radiation around the reactor pressure vessel, and the inside of the temporary opening. A third step of providing a seal curtain for storing the reactor pressure vessel; a fourth step of opening the door and carrying the reactor pressure vessel outside after storing the reactor pressure vessel in the seal curtain; and comprising a fifth steps to close the door the reactor pressure vessel after carried to the outside of the door,
The door has a double structure consisting of an upper door and a lower door that are slidable in opposite directions with respect to the central axis of the temporary opening,
Each of the upper door and the lower door has a semicircular cutout on the central axis side of the temporary opening, and a seal member is provided in each cutout. Unloading method. In the method of carrying out the reactor pressure vessel in which the reactor pressure vessel housed in the reactor building of the nuclear power plant is integrally carried out of the reactor building,
A first step of providing a temporary opening for opening and a door that can be opened and closed on the ceiling of the reactor building, a second step of providing a shield for shielding radiation around the reactor pressure vessel, and a lower side of the temporary opening. A third step of forming an air curtain for separating the temporary opening and the interior of the reactor building, a fourth step of opening the door and carrying out the reactor pressure vessel to the outside, and the reactor pressure vessel the includes a fifth steps to close the door after carried to the outside of the door,
The door has a double structure consisting of an upper door and a lower door that are slidable in opposite directions with respect to the central axis of the temporary opening,
Each of the upper door and the lower door has a semicircular cutout on the central axis side of the temporary opening, and a seal member is provided in each cutout. Unloading method. In the unloading switchgear used for unloading the reactor pressure vessel from the reactor building of the nuclear power plant,
A temporary opening for passing a reactor pressure vessel formed on the ceiling of the reactor building and provided with a shield for shielding radiation around the door, and a door provided at an upper portion of the temporary opening. Prepared,
The door has a double structure consisting of an upper door and a lower door that are slidable in opposite directions with respect to the central axis of the temporary opening,
The carry-out opening / closing device, wherein the upper door and the lower door each have a cutout portion having a semicircular cross section on the central axis side of the temporary opening portion, and a seal member is provided in each cutout portion. In the unloading switchgear used for unloading the reactor pressure vessel from the reactor building of the nuclear power plant,
A temporary opening for passing a reactor pressure vessel formed on the ceiling of the reactor building and provided with a shield for shielding radiation around it, and provided at the upper part of the temporary opening so as to be opened and closed A door and a seal curtain for storing therein a reactor pressure vessel provided inside the temporary opening and provided with the shield ,
The door has a double structure consisting of an upper door and a lower door that are slidable in opposite directions with respect to the central axis of the temporary opening,
The carry-out opening / closing device, wherein the upper door and the lower door each have a cutout portion having a semicircular cross section on the central axis side of the temporary opening portion, and a seal member is provided in each cutout portion.

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