JP6518511B2 - Method of opening reactor pressure vessel and method of taking out fuel debris - Google Patents

Description

  The present invention relates to a method of opening a reactor pressure vessel and a method of taking out fuel debris, and more particularly to a method of opening a reactor pressure vessel suitable for application to a boiling water nuclear power plant and a method of taking out fuel debris. About.

  In nuclear power plants such as boiling water nuclear power plants and pressurized water nuclear power plants, a sealed number of fuel assemblies containing nuclear fuel material are loaded in a core in a reactor pressure vessel. The fuel assembly loaded in the core is taken out of the reactor pressure vessel as a spent fuel assembly after experiencing operation of the nuclear power plant for a predetermined number of operation cycles from the time of loading in the core. Instead of the spent fuel assembly, a new burnup 0 WG d / t fuel assembly is loaded into the core in the reactor pressure vessel.

  For example, in a boiling water nuclear power plant, an emergency core cooling system provided with multiple cooling systems is provided so that each fuel assembly loaded in the core in the reactor pressure vessel is always cooled. . The installation of an emergency core cooling system prevents the occurrence of a core melting accident. However, with very low probability, the function of the emergency core cooling system may be lost and the fuel assembly loaded in the core may melt. A study has been made on a method of taking out molten nuclear fuel material when such fuel assembly melts.

  JP 2013-19875 describes a method for removing molten nuclear fuel material from a reactor pressure vessel in an air environment. In this method of taking out the molten nuclear fuel material, two working houses, which are isolation houses for preventing the scattering of radionuclides to the external environment, are stacked and placed on the operating floor of the reactor building so as to cover the reactor wells. A plug is installed on the operating bed so as to cover the reactor well, and using a boring device installed on the shield plug, the reactor containment head, the upper cover of the reactor pressure vessel, and the steam drying in the reactor pressure vessel And water separators are drilled. The state of the core is observed by a camera inserted into the core through the hole, and when the fuel assembly in the core is melted, the granular radiation shield is filled into the core through the hole.

  Thereafter, the head of the reactor containment vessel surrounding the reactor pressure vessel is cut by a cutting device disposed in the isolation house. The cut head is carried out. The top lid of the reactor pressure vessel is also removed. Furthermore, the steam dryer and the steam separator in the reactor pressure vessel are also carried out after being cut by the cutting device disposed in the isolation house.

  In the method for taking out the molten nuclear fuel material described in Japanese Patent Application Laid-Open No. 2013-19875, four additional floors, each of which has a guide rail with a quarter arc of one circle attached to the upper surface, are installed on the operating floor. Ru. By installing an additional floor on the operating floor, the guide rails on each additional floor are joined to form one circular guide rail. The electromagnet suspended from the overhead crane in the isolation house is attached to the outer surface of the head of the reactor containment vessel, and the cutting device is provided at the lower end of the telescopic tube of the cutting device while moving along the guide rails. The head of the reactor containment vessel is cut with a cutting device attached to the tip of the arm. The cut head is pulled up into the isolated house by pulling up the electromagnet suspended from the overhead crane and carried out to the outside. The upper lid of the reactor pressure vessel removes the bolt securing the upper lid to the reactor pressure vessel, and then the upper lid is attracted by an electromagnet and pulled up into the isolated house. If the bolt that secures the upper lid to the reactor pressure vessel can not be fixed and removed, like the head of the reactor containment vessel, the electromagnet suspended from the overhead crane in the isolated house is The upper lid is cut in a circle with a cutting device attached to the outer surface of the upper lid and moved along the above-mentioned guide rails, and the cut upper lid is pulled up into the isolated house.

  The steam dryer and the air-water separator installed in the reactor pressure vessel are respectively cut, and the cut pieces thereof are taken out in the isolation house. In Japanese Patent Application Laid-Open No. 2013-19875, thereafter, the fuel debris existing at the bottom of the reactor pressure vessel is taken out using a boring device.

  In addition, JP-A-2014-70946 forms an opening in the side wall of the reactor building, and through this opening, radiation toward the control rod drive mechanism hatch formed in the biological shielding body surrounding the reactor containment vessel. An access passage is formed by the shield, and it is described that fuel debris dropped to the bottom of the reactor containment vessel through this access passage is taken out. In this fuel debris retrieval method, a radiation shielding chamber is formed adjacent to the outer surface of the biological shielding body in the reactor building to be communicated with the access passage, and the articulated arm of the articulated access device disposed in the radiation shielding chamber. Crush the fuel debris that has fallen to the bottom of the reactor containment vessel in the pedestal by a crusher attached to the tip of the pedestal, grasp the fragments of the fuel debris with the gripper attached to the tip of the articulated arm and inside the pedestal Taken out to the radiation shielding room and stored in the storage container inside the radiation shielding room.

  In addition, JP 2012-255742A covers the reactor building with a secondary shielding tent and further covers the secondary shielding tent in the nuclear power plant where the core fuel melts and is subject to decommissioning work. Covered with a shielding tent. A crane unit is placed across the reactor building in the secondary shielding tent. The crane unit travels on guide rails installed on a plurality of columns installed outside the reactor building. A cutting piece such as a furnace internal structure or the like cut with a working device is stored in a storage container, and the storage container is placed on a transport carriage on a temporary support table by a crane unit and transferred to a predetermined storage building

Unexamined-Japanese-Patent No. 2013-19875 gazette JP, 2014-70946, A JP 2012-255742 A

  In the method for taking out the molten nuclear fuel material described in Japanese Patent Application Laid-Open No. 2013-19875, an isolation house is installed on the operation floor of the reactor building, covering the reactor well, and installed at the upper end of the reactor well. Remove the shield plug sealing off the well.

  When the shield plug is removed, the integrity of the containment vessel head is attached to the upper end of the reactor containment vessel, so the airtightness of the reactor containment vessel is maintained, and the reactor containment vessel even in the event of a core melt accident. No radioactive material is released into the reactor well formed above the containment head. However, if the containment of the containment head is compromised, radioactive material within the containment may have been released to the reactor well sealed with the shield plug. In such a case, by removing the shield plug that seals the reactor well, the radioactive material released to the reactor well intrudes into the isolated house and the inside of the isolated house is contaminated with the radioactive material. For this reason, radioactive materials accumulate in the isolated house itself and become a source of contamination, and the ambient dose equivalent rate rises, which prevents workers from approaching the isolated house. In addition, since various types of equipment installed in the isolated house are also contaminated, it is necessary to decontaminate all the equipment from the isolated house, which causes a decrease in workability.

In addition, if a hydrogen explosion occurs inside the reactor building due to the occurrence of a core melting accident, debris and structural members with radioactive materials assumed to be scattered on the operating floor of the reactor building 1 Removal work of falling objects such as pieces is carried out. Therefore, the method of removal work of falling objects affects the work thereafter.
In addition, there is a possibility of leakage of radioactive materials from the reactor containment vessel under the influence of the hydrogen explosion, which is feared of the possibility of leakage from the reactor building.
Since the working area is covered with the primary and secondary shielding tents described in JP 2012-255742 A, the reactor pressure vessel, which is the next operation, is opened and used immediately after removing the fallen objects. There is a problem that it is not possible to secure a work area that can be used in parallel with the spent fuel removal work.

  SUMMARY OF THE INVENTION It is a first object of the present invention to provide a method of simultaneously performing an operation for opening a reactor pressure vessel and an operation for discharging spent fuel.

  Another object of the present invention is to provide a method of opening a reactor pressure vessel which can reduce the risk of exposure.

  The feature of the present invention for achieving the above first object is that the reactor well connected to the equipment temporary storage pool and the equipment temporary storage pool is formed in the operation floor of the reactor building, and the reactor well is covered with a shield plug. The passage connecting the equipment temporary storage pool and the reactor well is closed with a throttle plug and placed in the reactor containment vessel of the nuclear power plant where the reactor containment vessel is placed inside the reactor building A method of opening a reactor pressure vessel, which is to secure a working space in which the operation of opening the reactor pressure vessel can be performed in parallel with the operation of taking out spent fuel from a fuel storage pool.

  It is possible to shorten the time for the entire series of operations from removal of falling objects to removal of fuel debris.

Another feature of the present invention for achieving the first and second objects described above is that a reactor well connected to the equipment temporary storage pool and the equipment temporary storage pool is formed in the operating floor of the reactor building, and the reactor well Is covered with a shield plug, the passage connecting the equipment temporary storage pool and the reactor well is closed with a throttle plug, and the reactor containment vessel in a nuclear power plant where the reactor containment vessel is disposed inside the reactor building A method of opening a reactor pressure vessel disposed therein, comprising:
Equipment temporary storage We will maintain an isolated area in the pool for air tightness and shielding.
The first through hole is formed in the throttle plug from the isolated area in the equipment temporary storage pool,
Provide a dismantling platform for the second radiation shield at the top of the reactor well,
The equipment in the reactor well is disassembled through the first through hole and carried out of the equipment temporary storage pool.

  Maintain the isolation area in the equipment storage pool opposite to the fuel storage pool and reactor well, and carry out the equipment in the reactor well through the isolation area to open the reactor pressure vessel. The work of opening the reactor pressure vessel is performed in parallel with the spent fuel unloading work from the fuel storage pool by performing at the top of the fuel storage pool performing the fuel rod removal work and at the top of the equipment temporary placement pool on the opposite side through the reactor well. Work area can be secured.

  In addition, since radiation from below the PCV head can be shielded by the dismantling platform that is also used as the second radiation shield, prevention of diffusion of radioactive dust from the reactor well and reduction of the radiation dose will It will correspond by the isolation area installed in the place pool, and it can prevent the spread of radioactive dust and the leak of a dose on the operation floor of a reactor building.

  Another feature of the present invention for achieving the second object described above is that after dismantling all the equipment in the reactor well covering the pressure vessel head attached to the reactor pressure vessel and taking it out of the radiation shielding vessel , The second through hole is made in the pressure vessel head, the camera is inserted from the second through hole, the inside of the pressure vessel head is inspected, and then the equipment in the nuclear pressure vessel is carried out outside the reactor building .

  Since the internal state of the reactor pressure vessel can be grasped in advance, the time required for carrying out the internal equipment pressure vessel can be shortened, and the leak of the radiation duct and the dose generated accordingly can be prevented.

  In addition, the leakage of radioactive materials from the reactor building can be prevented by installing a cover over the entire reactor building and managing the negative pressure, and this cover can be used to remove falling objects from the reactor building and The combined use makes it possible to standardize the cover on the operating floor of the reactor building in each work step of removal of fallen objects, removal of spent fuel, and removal of fuel debris.

  According to the present invention, it is an object of the present invention to provide a method in which the opening operation of the reactor pressure vessel and the spent fuel unloading operation can be performed in parallel to further reduce the time required for the entire operation.

  Further, according to the present invention, it is possible to provide a method for opening a reactor pressure vessel which can reduce the risk of exposure.

It is a longitudinal cross-sectional view of the reactor building of a boiling water type nuclear power plant. It is a top view of the operation floor of a reactor building. It is a flowchart which shows a part of procedure of the fuel debris removal method of Example 1 applied to the boiling water type nuclear power plant which is one preferable embodiment of this invention. 5 is a flowchart showing the rest of the procedure of the fuel debris removal method of Embodiment 1. FIG. It is explanatory drawing which shows the state which mainly installed the whole cover apparatus which mainly covers the upper part from the operation floor which performs falling object removal, and covers the whole reactor building. It is explanatory drawing which shows the operation | work concept which removes a falling thing using an isolation film. It is explanatory drawing which shows the operation | work concept which removes a falling thing using an apparatus inclusion container, without using a separation film. It is explanatory drawing which shows the state which installed the radiation shielding container in the dryer separator pool. It is explanatory drawing which shows the carrying-in state of the perforation | piercing apparatus in the radiation shielding container installed in the dryer separator pool. It is explanatory drawing which shows the state of the perforation | punching apparatus installed in the front of the throttle plug for perforation | punching object in a radiation shielding container. It is explanatory drawing which shows the state which pierces a throttle plug using a piercing device. It is explanatory drawing which shows the state which took out the block which the throttle plug cut | disconnected. It is explanatory drawing which shows the installation state of the handrail removal apparatus in a radiation shielding container. It is explanatory drawing which shows the removal operation | work of the handrail of the containment vessel head arrange | positioned in a reactor well using the handrail removal apparatus. It is explanatory drawing which shows the installation state of the decontamination apparatus in a radiation shielding container. It is an explanatory view showing decontamination work in a reactor well using a decontamination apparatus. It is explanatory drawing which shows the installation state of the radiation shielding body installation apparatus in a radiation shielding container. It is explanatory drawing which shows the carrying-in operation | work of the radiation shielding bag in a reactor well using a radiation shielding body installation apparatus. It is explanatory drawing which shows the state of the radiation shielding bag which was carried in in the reactor well and expanded by the water supply to the inside. It is explanatory drawing which shows the state which covered the container head by several radiation shielding bags arrange | positioned in a reactor well and expanded by water supply. It is explanatory drawing which shows the state which installed the isolation house which covers a dryer separator pool and a reactor well on the operation floor of a reactor building. It is explanatory drawing which shows the removal operation of a shield plug. It is explanatory drawing which shows the state which accommodates the removed shield plug in the carrying out container arrange | positioned on the upper surface of the radiation shielding container in the isolation house. It is explanatory drawing which shows the removal operation of a slot plug. It is explanatory drawing which shows the state in the middle of conveyance of the removed slot plug. It is explanatory drawing which shows the state which accommodates the removed slot plug in the carrying out container arrange | positioned on the upper surface of the radiation shielding container in the isolation house. It is explanatory drawing which shows the state which removed the side wall by the side of the reactor well of the radiation shielding container installed in the dryer separator pool. The separation wall dividing the inside of the isolation house into the first area directly above the dryer separator pool and the second area directly above the reactor well, and the attachment of new side walls to the reactor well side of the radiation shielding container, and It is explanatory drawing which shows the attachment state of each new side wall to the reactor well side of a radiation shielding container, and the delivery operation | work of the radiation shielding bag in a reactor well. It is explanatory drawing which shows cutting | disconnection of the storage container head by the cutting-and-recovery apparatus provided in the radiation shielding container, and a pool fuel extraction process. It is explanatory drawing which shows cutting | disconnection of the heat insulating material by the cutting-and-collecting apparatus provided in the radiation shielding container. It is explanatory drawing which shows the removal operation of a baffle plate, and the attachment operation | work of a pressure vessel support body and a radiation shielding board. It is explanatory drawing which shows the investigation process which investigates the inside of a reactor containment vessel. It is explanatory drawing which shows the state which has arrange | positioned the isolation vessel which covers a pressure vessel head in each inside of the reactor well and the 2nd area in an isolation house. It is an explanatory view showing a state where the pressure vessel head is lifted in the isolation vessel. It is explanatory drawing which shows the decontamination operation | work of the inner surface of the pressure vessel head lifted in the isolation container. It is explanatory drawing which shows carrying out out of the isolation container of the pressure vessel head decontaminated. It is explanatory drawing which shows the removal operation | work of the steam dryer in an isolation container. It is explanatory drawing which shows carrying out out of the isolation container of the removed steam dryer. It is explanatory drawing which shows the carrying in in the radiation shielding container installed in the dryer separator pool of the removed steam dryer. It is explanatory drawing which shows the other example of the removal operation | work of the steam dryer in an isolation container. It is explanatory drawing which shows the cutting operation of the reactor internals in the reactor pressure vessel by a rotary cutting device. FIG. 40 is a side view of the rotary cutting device shown in FIG. 39. It is the YY arrow line view of FIG. It is explanatory drawing which shows carrying out of a carrying out container via the water ring area in the storage container head cutting | disconnection of FIG. It is explanatory drawing which shows another figure of the investigation process which investigates the reactor containment vessel inside of FIG. It is explanatory drawing which shows the shredding process which is another figure of the removal process of the pressure vessel head of FIGS. 31-34. It is explanatory drawing which shows the shredding in the radiation shielding container which is another figure of the removal process of the steam dryer of FIGS. 35-37.

  A method of removing falling objects and a method of removing fuel debris according to a preferred embodiment of the present invention will be described below with reference to FIGS. 3 and 4. The fuel debris extraction method of this embodiment is applied to a boiling water nuclear power plant. The fuel debris removal method of this embodiment includes the opening of the reactor pressure vessel and the removal of fuel debris.

  The method for opening the reactor pressure vessel, which is a part of the fuel debris removal method of the present embodiment, includes the preparation operation (including the steps S1 to S6) and the reactor opening operation (step S7) shown in FIG. Through S13) are included. This fuel debris removal method includes a removal operation (including the respective steps of steps S14 to S16) of the fuel debris dropped to the bottom of the reactor containment vessel shown in FIG.

  Before describing the fuel debris removal method of the present embodiment, a schematic configuration of a boiling water nuclear power plant to which this fuel debris removal method is applied will be described using FIGS. 1 and 2. FIG.

  The boiling water nuclear power plant 1 includes a reactor 2 and a reactor containment vessel 17. The reactor containment vessel 17 is installed in the reactor building 23, and the containment vessel head 18 which is a lid is attached and sealed at the upper end. The reactor containment vessel 17 has a dry well 19 formed therein, and a pressure suppression chamber 21 in which a pressure suppression pool filled with cooling water is formed. One end of a vent passage in communication with the dry well 19 is immersed in the cooling water of the pressure suppression pool in the pressure suppression chamber 21. The reactor containment vessel 17 is surrounded by a biological shield 100 which becomes a part of the reactor building 23.

  Shield plugs 28, which are a plurality of divided radiation shields, are disposed directly above the containment head 18, and these shield plugs 28 are disposed in the reactor well 25 and are disposed on the operation floor 24 of the reactor building 23. is set up. The shield plug 28 seals the reactor well 25. A dryer separator pool (instrument temporary storage pool) 26 and a fuel storage pool 27 are disposed adjacent to the reactor well 25 and surrounded by the operating floor 24. The dryer separator pool is hereinafter referred to as DSP. The DSP 26, the reactor well 25 and the fuel storage pool 27 are arranged in a straight line as shown in FIG. The DSP 26 and the reactor well 25 are connected by a water channel, and this water channel is sealed at least during operation of the boiling water nuclear power plant 1 by a plurality of throttle plugs (gate members) 29A. The throttle plugs 29A are stacked on the top surface of a concrete projection 57 formed at the bottom of the water channel. The reactor well 25 and the fuel storage pool 27 are also connected by a water channel, and this water channel is sealed at least by the plurality of stacked throttle plugs (gate members) 29 B during the operation of the boiling water nuclear plant 1.

  The reactor 2 includes a reactor pressure vessel 3 configured by attaching a pressure vessel head 4 as a lid, a core 7 on which a plurality of fuel assemblies 8 containing nuclear fuel material are loaded, a steam separator 11, and steam drying. And the like. The reactor core 7, the steam separator 11 and the steam dryer 12 are disposed in the reactor pressure vessel 3. A core shroud 6 installed in the reactor pressure vessel 3 surrounds the core 7. The lower end portion of each fuel assembly 8 loaded in the core 7 is supported by the core support plate 9, and the upper end portion is held by the upper grid plate 10. The steam-water separator 11 is disposed above the upper grid plate 10 located at the upper end of the core 7, and the steam dryer 12 is disposed above the steam-water separator 11.

  A plurality of control rod guide tubes 13 are disposed in the reactor pressure vessel 3 below the core support plate 9. Control rods (not shown) that are inserted in and out of the fuel assemblies 8 in the core 7 to control the reactor power are disposed in each control rod guide tube 13. A plurality of control rod drive mechanism housings 14 are attached to the lower mirror 5 of the reactor pressure vessel 3. A control rod drive mechanism (not shown) is installed in each control rod drive mechanism housing 14 and coupled with the control rod in the control rod guide tube 13.

  The core shroud 6, the core support plate 9, the upper lattice plate 10, the steam separator 11, the steam dryer 12 and the control rod guide pipe 13 installed in the reactor pressure vessel 3 are internal components of the reactor.

  The reactor pressure vessel 3 is installed on a cylindrical pedestal 15 provided on a concrete mat 16 provided at the bottom of the reactor containment vessel 7. A cylindrical γ-ray shield 22 is disposed at the upper end of the pedestal 15 and surrounds the reactor pressure vessel 3. A lower plenum 20 is formed in the pedestal 15 below the reactor pressure vessel 3.

  In such a boiling water nuclear power plant 1, all the power supplied to the boiling water nuclear power plant 1 temporarily disappears in a state where the reactor is scramed and the reactor power is reduced, and the emergency core cooling Assume that a condition has occurred where the system did not operate. In the case where all power is lost, the pumps of the emergency core cooling system, etc. become inoperable and the cooling of each fuel rod included in each fuel assembly 8 in the core 7 is impaired, The contained nuclear fuel material melts, and by melting the nuclear fuel material, the structural members of the fuel assembly 8, for example, the cladding of the fuel rod, the channel box of the fuel assembly 8 and the upper tie plate and the lower tie plate are also melted. Fuel debris 39A, which is a melt of nuclear fuel material and structural members of the fuel assembly 8, may fall on the inner surface of the lower mirror 5, which is the bottom of the reactor pressure vessel 3. The fuel debris 39A may include a melt of core internals such as the core support plate 9 and the like. The fuel debris 39A melted and dropped onto the inner surface of the lower mirror portion 5 is cooled and solidified.

  Should such fuel debris 39A fall to the bottom of the reactor pressure vessel 3, removal of the solidified fuel debris 39A from the reactor pressure vessel 3 is carried out, and further fuel debris 39A is removed. The decommissioning process is carried out for the boiling water nuclear power plant 1 in which the falling occurs. In addition, a part of the fuel debris 39A dropped to the bottom of the reactor pressure vessel 3 is the bottom of the reactor containment vessel 17 in the pedestal 15 below the lower mirror 5 of the reactor pressure vessel 3, that is, concrete There is also a possibility of falling on the mat 16. The fuel debris that has fallen to the bottom of the reactor containment vessel 17 within the pedestal 15 is referred to as fuel debris 39B.

  When a core melting accident in which the nuclear fuel material in the core 7 melts occurs, nothing is present in the DSP 26 as shown in FIG. 5, and the DSP 26 and the reactor well 25 are partitioned by the plurality of slot plugs 29A. ing. In addition, a handrail 31 is provided on the top of the storage container head 18, and the pressure container head 4 is covered with a heat insulating material 30. Between the reactor pressure vessel 3 and the containment vessel 17, a baffle plate 76 which is a part of the bottom of the reactor well 25 is disposed. The baffle plate 76 is a reactor pressure vessel 3 and the containment vessel 17. Is attached to It is assumed that gas containing radioactive material (for example, Cs-137 or the like) flows out into the reactor well 25 through the damaged portion of the containment vessel head 18 due to the occurrence of a core melting accident.

First, when a hydrogen explosion occurs in the reactor building due to the occurrence of a core melting accident, debris and structural members with radioactive materials assumed to be scattered on the operating floor of the reactor building 1 A reactor building preparation operation mainly for removing falling objects such as fragments will be described with reference to FIGS. 5A to 5C.
In the reactor building preparation work, first, the building cover which has been erected at a place which needs to be removed for each work is disassembled on the operation floor 24 of the existing reactor building 23 (step ST1).

  Thereafter, as shown in FIG. 5A, an entire cover device covering the entire reactor building 23 is installed with the upper part from the operation floor 24 for removing the falling objects as the main (step ST2). FIG. 5A (a) is the figure which looked at the whole cover apparatus 300 from the upper part. FIG. 5A (b) is a side cross-sectional view of the entire cover apparatus including the reactor building 1 in FIG. 5A (a). As shown in FIG. 5A (a), the overall covering device 300 has at least four columns erected at four corners of the reactor building 1, and is isolated to cover the upper surface of the device and its four sides in order to isolate radioactive material. Sheets 303A and 303B are provided. In the general cover device 300, a traveling member and a traversing member for moving the traveling carriage 301 having the article loading opening 301A two-dimensionally in the upper part of the operation floor 24 are attached to a frame member defining its shape.

  According to the present overall cover device, a sufficient working space can be formed between the traveling carriage 301 and the operation floor 24, and an environment is provided in which, for example, a plurality of operations can be performed independently and in parallel after the dropped object removal operation is completed. it can.

  FIG. 5B is a view showing an operation concept of removing the falling object 310 using the isolation film 309. In the present example, as shown in FIG. 5B (a), a loading device 306 is provided on the upper side of the article loading port 301A, and a gripping tool 308 is provided movably up and down from the traveling carriage 307 of the loading device 306. Have.

First, the article loading opening 301A is moved to the upper part of the position where the falling object 310 exists based on, for example, a survey conducted in advance, and the picker 308 is conveyed to the top of the article loading opening 301A (FIG. 5B (a)). Thereafter, the picker 308 is lowered and inserted from the article loading opening 301A, and the falling object 310 is gripped (FIG. 5B (b)). Next, the falling object 310 is pulled up through the article loading opening 301A, the picker 308 is rotated, the holding object 310 is wrapped with the separation film 309, and the rotated and squeezed position is fused. It separates (figure 5B (c)). Thereafter, the falling object wrapped with the isolation film 309 is moved to the position of the container holder 312 with the discharge container 311 and stored (FIG. 5B (d)). Thereafter, the hook of the crawler crane 305 is moved to the position of the container pedestal 312, the unloading container 311 is unloaded to a predetermined position, and the article loading port 301A is closed (FIG. 5B (e)).
Although the traveling carriage 307 is used in this example, the picker 308 may be moved up and down by a crane moving integrally with the article loading port 301A.

  FIG. 5C is a diagram showing a concept of removing the falling object 310 using the apparatus-containing container 313 without using the separation film 309. FIG. 5C (a) in this example shows a state in which the device-containing container 313 is placed on the article loading opening 301A without the isolation film 309. A traveling carriage 307 and a picker 308 are incorporated in the apparatus-containing container 313. In addition, an openable and closable sheet 314 is provided on the lower surface of the device-containing container 313 and the upper surface of the article loading opening 301A.

First, the article loading opening 301A is moved to the upper part of the position where the falling object exists based on, for example, a survey conducted in advance, and thereafter, the device inner container 313 is placed on the article loading opening 301A (FIG. 5C (a)) . Next, the both opening and closing sheets 314 are opened, the picker 308 is lowered, and is inserted from the article loading port 301A, and the falling object 310 is gripped (FIG. 5C (b)). Thereafter, the falling object 310 is collected into the apparatus-containing container 313, and the both openable and closable sheets 314 are closed (FIG. 5C (c)). Then, for example, the device contained container 313 from which the falling object 310 has been collected is lifted by the crawler crane 305 (FIG. 5C (d)), moved to the position of the container holder 312 with the discharge container 311, opened the opening / closing sheet, and stored The object is transferred to the unloading container (FIG. 5C (e)). Thereafter, the apparatus-containing container 313 is again lifted by the crawler crane 305 and moved to the next collection position. After the movement, the unloading container 311 is lifted by another crawler crane 305, and is unloaded to a predetermined position (FIG. 5C (f)).
In this example, the apparatus containing container 313 is placed on the article loading opening 301A and the falling objects are collected, but a traveling carriage for moving the apparatus containing container 313 and the apparatus containing container 313 is provided below the article loading opening 301A. It may be

  After performing the reactor building preparation work described above, the overall cover device installed in the work space formed between the traveling carriage 301 and the operation floor 24 connects an exhaust device (not shown) inside thereof Since the airtightness can be secured by controlling the negative pressure, it can be used commonly for the subsequent opening operation of the reactor pressure vessel and the spent fuel unloading operation. Further, as will be described later, in the opening operation of the reactor pressure vessel, it is possible to use the carry-out container storing the take-out equipment of the device in the reactor well out from the article carry-in port 301A. In addition, even in the spent fuel unloading operation from the fuel storage pool 27, the article loading port 301A can be used for carrying in and out the contaminated equipment used in the pool, which can also contribute to performing both operations in parallel. In addition, since the whole reactor building is covered, if radioactive material leaks from the reactor containment vessel 17 and leakage from the reactor building occurs, diffusion to the surrounding environment is achieved by the overall cover device. It can prevent.

  As a result, there is no need to replace the dedicated cover according to the subsequent work after removing the debris on the operation floor, and there is no need to sequentially perform the opening work of the reactor pressure vessel and the spent fuel removal work. The time required for dismantling the reactor can be further reduced.

  Next, the method of taking out fuel debris according to this embodiment will be described below. First, the preparation operation in the method of opening the reactor pressure vessel, which is a part of the fuel debris removal method of the present embodiment, will be described. This preparation work is a pre-work for the reactor opening work.

  A radiation shielding container is installed in the DSP as an example for maintaining the inside of the equipment temporary storage pool as an isolation area for shielding the inside and preventing the diffusion of radioactive substances (step S1). The radiation shielding container 32 is lifted and installed in the DSP 26 using a movable crawler crane (not shown) installed outside the reactor building 23 (see FIG. 6). In addition, this crane should just be what can carry in and out heavy goods, such as a gate type crane and a tower crane, integrally. The radiation shielding container 32 is attached to the radiation shielding container 32 as a ceiling member with the radiation shielding plate 33 having the opening 36A formed therein, and the opening 36B is formed on the side wall on the reactor well 25 side. The radiation shielding container 32 is attached with a movable door 34 for opening and closing the opening 36A. In addition, a movable door 35 for opening and closing the opening 36B is attached to the inner surface of the side wall on the reactor well 25 side. The opening 36 B is closed by the door 34 and the opening 36 B is closed by the door 35.

  A through hole is formed in the throttle plug (step S2). The isolation chamber 40 in which the perforation device 41 is accommodated is suspended by the crawler crane and carried into the space 37 in the radiation shielding container 32 through the opening 36A (see FIG. 7). At this time, the door 34 is open. A carriage 40A is attached to the lower surface of the isolation chamber 40, and an opening 40E is formed in one side wall of the isolation chamber 40. The opening 40E is opened and closed by a door 40B movably attached to the inner surface of the side wall. An annular sealing device 40C surrounding the opening 40E is attached to the outer surface of the side wall of the isolation chamber 40.

  The piercing device 41 is disposed in the space 40D in the isolation chamber 40, and is movably attached to the upper end of the support member 42 attached to the bottom of the isolation chamber 40. After the isolation chamber 40 is carried into the radiation shielding container 32, the door 34 is closed, and the isolation chamber 40 is moved by the carriage 40A to the side wall of the radiation shielding container 32 on the reactor well 25 side. The sealing device 40C is pressed against the inner surface of the side wall of the radiation shielding container 32 in which the opening 36B is formed by the movement of the isolation chamber 40 so as to surround the opening 36B (see FIG. 8). The door 35 is opened after the sealing device 40C is pressed against this side wall. The opening 36B is in communication with the opening 40E formed in the isolation chamber 40, and is in communication with the space 40D in the isolation chamber 40 by opening the door 40B.

  By driving the perforation device (for example, a wire saw) 41 and moving the perforation device 41 toward one concrete throttle plug 29A, the throttle plug 29A is cut into blocks. The cut position of the throttle plug 29A using the drilling device 41 is a position lower than the lower surface of the shield plug 28 located at the lowest position among the shield plugs 28 closing the reactor well 25 (see FIG. 9). . The block 44 of the shield plug 28 cut out by the piercing device 41 is carried into the isolation chamber 40 (see FIG. 10). As a result, the through hole 43 is formed in the shield plug 28, the reactor well 25 and the space in the isolation chamber 40 communicate with each other, and the gas containing the radioactive substance present in the reactor well 25 is the through hole 43 and the opening Flow into isolation chamber 40 through 36B and 40E. Thereafter, the door 40B is closed to close the opening, and immediately the door 35 is closed to close the opening.

  The isolation chamber 40 in which the door 35 is closed and sealed, and the gas containing the radioactive substance is present therein, is carried out from the inside of the DSP 32 to the ground by the crawler crane through the opening 36A. Thereafter, the isolation chamber 40 containing the perforating device 41 is disposed of, at which the gas containing radioactive material in the isolation chamber 40 is supplied to the purification device and removed by the purification device.

  The handrails provided on the containment head are removed (step S3). Another isolation chamber 40 in which the handrail removing device 45 is housed is carried into the space 37 in the radiation shielding container 32 through the opening 36A as in the process of step S2. After loading the isolation chamber 40, the door 34 is closed. The isolation chamber 40 is moved within the radiation shielding container 32 until the sealing device 40C contacts the inner surface of the side wall of the radiation shielding container 32 on the reactor well 25 side (see FIG. 11). The door 35 is opened after the sealing device 40C is pressed against this side wall.

  The handrail removing device 45 has a slide mechanism 45B attached to the upper end of the support member 42, an expandable tube 45A installed on the slide mechanism 45B, and two working arms 45C attached to the tip of the expandable tube 45A. A gripper (not shown) is attached to the tip of one working arm 45C, and a cutter (pipe cutter) is attached to the tip of the other working arm 45C. These working arms 45C have multiple joints and can be freely bent vertically and horizontally. The working arm 45 </ b> C includes, for example, a plurality of actuators 200 ′ described in JP 2011-106529 A and coupled to each other.

  The door 40 B is opened and the space 40 D in the isolation chamber 40 is in communication with the reactor well 25. By the movement of the slide mechanism 45 B, the telescopic tube 45 A is inserted into the through hole 43, and the telescopic tube 45 A is further extended toward the reactor well 25. The handrail 31 attached to the storage container head 18 is grasped by the grasping tool of one working arm 45C, and cut by the cutter of the other working arm 45C (see FIG. 12). The cut piece of the handrail 31 gripped by the above-described gripping tool is moved into the isolation chamber 40 by the movement of the slide mechanism 45B and the telescopic tube 45A, and is stored in the isolation chamber 40. Thus, the handrails 31 are sequentially cut. After all the handrails 31 have been removed, the working arm 45C of the handrail removal device 45 is housed in the isolation chamber 40, and the doors 40B and 35 are closed. The isolation chamber 40 containing the handrail removing device 45 and the cut pieces of the handrail 31 is suspended by the crawler crane and transported from the radiation shielding container 32 to the ground through the opening 36A.

  A camera (not shown) is attached to the tip of the expandable tube 45A to which the working arm 45C is attached, and the camera captures an operation (for example, cutting of the handrail 31) in the reactor well 25. The image taken by the camera is transmitted to the monitor of the operation floor of the reactor building 23 or an operation room installed in a separate building, and is monitored by a worker. This camera is also attached to the distal end portion of each telescopic tube 45A of the decontamination apparatus 46 and shield transfer device 47 used in steps S4 and S5 described later.

  The inside of the reactor well is decontaminated (step S4). Another isolation chamber 40 in which the decontamination apparatus 46 is housed is carried into the radiation shielding container 32 through the opening 36A in the same manner as the process of step S2, and then the door 34 is closed. The sealing device 40C of the isolation chamber 40 is in contact with the inner surface of the side wall of the radiation shielding container 32 on the reactor well 25 side (see FIG. 13). The door 35 is opened after the sealing device 40C is pressed against this side wall.

  The decontamination apparatus 46 has a slide mechanism 45B attached to the upper end of the support member 42, a telescopic tube 45A, and a working arm 45C, as with the handrail removal apparatus 45. The injection nozzle 46A is attached to the tip of the working arm 45C.

  The door 40 B is opened and the space 40 D in the isolation chamber 40 is in communication with the reactor well 25. As the slide mechanism 45 B and the expansion tube 45 A move toward the reactor well 25, the working arm 45 C and the injection nozzle 46 A are inserted between the containment head 18 and the shield plug 28 in the reactor well 25. Cleaning water is injected from the injection nozzle 46A, and for example, decontamination of the lower surface of the shield plug 28 is performed (see FIG. 14). The washing water is supplied by a water supply hose (not shown) installed along the telescopic tube 45A and the working arm 45C. The water supply hose extends from the inside of the isolation chamber 40 to the outside of the radiation shielding container 32 and is connected to the makeup water system. The telescopic tube 45A is expanded and contracted to bend the working arm 45C vertically and horizontally to decontaminate the outer surface of the containment head 18 and the inner surfaces of the throttle plugs 29A and 29B. After the decontamination in the reactor well 25 is completed, the working arm 45C and the jet nozzle 46A of the decontamination apparatus 46 are accommodated in the isolation chamber 40, and the doors 40B and 35 are closed. The isolation chamber 40 containing the decontamination apparatus 46 is suspended by the crawler crane and transported from the radiation shielding container 32 to the ground through the opening 36A.

  The washing water sprayed and dropped from the jet nozzle 46A toward the lower surface of the shield plug 28 at the time of decontamination is received by the washing water receptacle (not shown) attached to the working arm 45C and connected to the washing water receptacle It is stored in a drainage tank (not shown) provided in the isolation chamber 40 through a drainage hose. Washing water used to decontaminate the outer surface of the containment head 18 and the inner surfaces of the throttle plugs 29A and 29B can not be received by the washing water receiver and falls onto the upper surface of the baffle plate 76 in the reactor well 25. . The washing water dropped to the upper surface of the baffle plate 76 is driven by a pump (not shown) connected to the drainage tank of the isolation chamber 40 and suctioned by a drainage hose (not shown) connected to the pump, and drained. It is stored in the tank. Water stored in the drainage tank is also transported to the ground along with the isolation chamber 40.

  The first radiation shield is installed in the reactor well (step S5). Another isolation chamber 40, in which the shield transport device 47 and the folded shield bag 48 are housed, is carried into the radiation shield container 32 through the opening 36A, as in the process of step S2, and then the door 34 is closed. The shielding bag 48 is a bag made of a composite sheet composed of a sheet having elastic properties and fibers maintaining strength, and is a fold. This sheet may be one incorporating high-strength, high-elasticity, high-ductility fibers as required. The shielding bag 48 may be made of stretchable rigid rubber. The sealing device 40C of the isolation chamber 40 is in contact with the inner surface of the side wall of the radiation shielding container 32 on the reactor well 25 side (see FIG. 15). The door 35 is opened after the sealing device 40C is pressed against this side wall.

  Similar to the handrail removal device 45, the shield transfer device 47 has a slide mechanism 45B attached to the upper end portion of the support member 42, a telescopic tube 45A, and a working arm 45C. A gripper 47A is attached to the tip of the working arm 45C.

  The door 40 B is opened and the space 40 D in the isolation chamber 40 is in communication with the reactor well 25. In the space 40D, the grasping tool 47A grasps one shielding bag 48 present in the space 40D. As the slide mechanism 45B and the telescopic tube 45A move toward the reactor well 25, the working arm 45C and the gripping tool 47A gripping the shielding bag 48 in the reactor well 25 include the containment head 18 and the shield plug 28. Inserted between The shielding bag 48 gripped by the gripping tool 47A is moved to a predetermined position in the reactor well 25 above the containment head 18 (see FIG. 16). Thereafter, a water supply hose (not shown) installed along the telescopic pipe 45A and the working arm 45C is connected to a check valve provided in the shielding bag 48, and water supplied by the water supply hose is provided with a check valve. It is supplied into the shielding bag 48 through the one-touch coupler. The shielding bag 48 is inflated by the supply of water and covers a portion of the containment head 18 and is disposed between the containment head 18 and the shield plug 28 (see FIG. 17).

  The water supply hose installed along the working arm 45C is removed from the one-touch coupler with its check valve, and the movement of the slide mechanism 45B and the telescopic tube 45A returns the gripper 47A to the space 40D in the isolation chamber 40. Here, the gripping tool 47A grips the other shielding bag 48 and moves again to a predetermined position in the reactor well 25 to transfer the shielding bag 48 to the predetermined position. Water is also supplied to the inside of the shielding bag 48, and the shielding bag 48 is inflated. Thus, the necessary number of shield bags 48 are transferred into the reactor well 25 and expanded with water, whereby the containment head 18 is disposed between the containment head 18 and the shield plug 28, It is covered with a plurality of shielding bags 48 inflated with water (see FIG. 18). These shielding bags 48 filled with water serve as a radiation shielding body (first radiation shielding body).

  Since the through hole 43 is formed in the throttle plug 29A, the radiation shielding container 32 installed in the DSP 26 using the shield transfer device 47 in the isolation chamber 40 through the through hole 43 from the radiation shielding container 32 and the shield plug 28 Can be easily transported between Thus, the water-filled shielding bag 48 covering the containment head 18, that is, the first radiation shielding body can be easily installed.

  By placing the water-filled shielding bags 48 between the containment head 18 and the shield plug 28, radiation from below the containment heads 18 is water-filled shielding bags 48. It can be shielded. As a result, diffusion of radioactive materials from the reactor well and leakage of dose from the reactor well are established in the equipment temporary placement pool by accessing the decontamination and shield installation work in the contaminated reactor well from the equipment temporary placement pool side. The radiation shielding container can be used to prevent radioactive dust and radiation from leaking directly to the operating floor. Further, as described later, even when the shield plug 28 is removed, the dose on the operating floor 24 can be reduced. In addition, since the shielding bags 48 filled with water are disposed in the reactor well 25, the flow of air in the reactor well 25 is impeded, and the diffusion of radioactive materials can be prevented.

  After the installation of the predetermined number of water-filled shielding bags in the reactor well 25 is completed, the working arm 45C and the gripping tool 47A of the shielding body transfer device 47 are stored in the isolation chamber 40, and the doors 40B and 35 are installed. Is closed. The isolation chamber 40 containing the shield transfer device 47 is suspended by the crawler crane and transferred from the radiation shield container 32 to the ground through the opening 36A.

  In addition, while performing each process of step S1-S6, the upper surface of the shield plug 28 which has sealed the reactor well 25 is covered with the curing sheet 38. As shown in FIG. The curing sheet 38 suppresses leakage of radionuclides from between the shield plugs 28.

  An isolation house is installed on the operating floor of the reactor building (step S6). The isolated house 49 is transported onto the operating floor 24 of the reactor building 23 using a crawler crane, and the isolated house 49 is installed on the operating floor 24 (see FIG. 19). The isolation house 49 covers the DSP 26, ie the radiation shielding vessel 32 and the reactor well 25. The side wall of the isolation house 49 is formed with an opening (not shown) serving as an entrance to and from the isolation house 49, and a door (not shown) for opening and closing the opening is movably attached. A worker can enter the space 53 in the isolation house 49 from above the operating floor 24 through its opening formed in the side wall of the isolation house 49 with an open door. An overhead crane 50 including a traveling carriage and a traversing carriage is movably installed on a guide rail 51 installed near the ceiling in a space 53 in the isolated house 49. The traversing carriage of the overhead crane 50 is fitted with a rotating drum (not shown) for winding and unwinding the wire 56 attached to the gripper 52.

  Thus, each step of the preparatory work in the method of opening the reactor pressure vessel is completed. Next, the reactor opening operation in the method of opening the reactor pressure vessel will be described.

  Remove the shield plug (step S7). An annular isolation film storage container 73 is disposed on the radiation shielding container 32, the operating floor 24, and the throttle plug 29B in the isolation house 49 so as to surround the throttle plug 29A and the shield plug 28. The isolation film 54 taken out of the isolation film storage container 73 is disposed to cover the throttle plug 29A and the shield plug 28 above. The gripper 52 of the overhead crane 50 grips a hanger (not shown) attached to one shield plug 28 from above the isolation film 54 (see FIG. 19). The wire 56 is wound to lift the shield plug 28 to a predetermined position (see FIG. 20). Then, the lifted shield plug 28 is wrapped with the isolation film 54, and the isolation film 54 is welded at the position of X shown in FIG. 20 which is wrapped and squeezed, and the isolation film 54 is cut at the welded portion.

  Thereafter, the overhead crane 50 is moved, and the shield plug 28 wrapped with the isolation film 54 is made of radiation shielding material placed on the radiation shielding plate 33 attached to the radiation shielding container 32 in the isolation house 49. It is stored in the carry-out container 55 (see FIG. 21). The discharge container 55 containing the shield plug 28 is discharged onto the operation floor 24 through the above-mentioned opening with the door open, and further transported to the ground using a crawler crane and further transported to a predetermined storage location. . The remaining shield plugs 28 are similarly transported.

  Remove the throttle plug (step S8). Because all the shield plugs 28 have been removed, the containment head 18 is covered with a water-filled shielding bag 48 so that radiation from below the containment head 18 is water-filled shielding. It is shielded by the bag 48 and does not reach the space 53 in the isolated house 49. An isolation film 54 removed from the isolation film storage container 73 is disposed over the throttle plug 29A and the water-filled shielding bag 48 in the reactor well 25. The gripper 52 of the overhead crane 50 grips a hanger (not shown) attached to one throttle plug 29A from above the isolation film 54 (see FIG. 22). The wire 56 is wound to lift the throttle plug 29A to a predetermined position, and the lifted throttle plug 29A is wrapped with the isolation film 54, and similarly to the shield plug 28, the isolation film 54 is welded and welded at the wrapped position. The separation film 54 is cut at a portion (see FIG. 23).

  Then, the overhead crane 50 is moved, and the shield plug 28 wrapped in the isolation film 54 is stored in the discharge container 55 disposed in the isolation house 49 (see FIG. 24). The discharge container 55 storing the throttle plug 29A is transported to the ground and transported to a predetermined storage location, similarly to the discharge container 55 storing the shield plug 28. The remaining throttle plug 29A is similarly transported.

  Thereafter, each step of steps S8A to S8D which is not shown in FIG. 3 which is a part of the reactor opening operation is performed. Each process of steps S8A to S8E will be described below.

  The side wall on the reactor well 25 side of the radiation shielding container 32 is removed (step S8A). The side wall on the reactor well 25 side of the radiation shielding container 32 is removed from the radiation shielding container 32 with the door 35 attached, and is lifted by the overhead crane 50 and transferred to the space 53 in the isolated house 49. Furthermore, the side wall is transferred from inside the isolated house 49 onto the operating floor 24 outside the isolated house 49 and transported to the ground. If necessary, the side wall is cut into a plurality of cutting pieces and transferred for each cutting piece. FIG. 25 shows the state in which the side wall is removed.

  The protrusion formed on the bottom of the water channel connecting the DSP and the reactor well is removed (step S8B). The isolation chamber 40 in which the punching device 41 used in step S2 is stored is transported from the ground to the operation floor 24 by the crawler crane, and moved into the isolation house 49 from the above-mentioned opening formed in the isolation house 49. Ru. Although not shown in FIG. 25, the isolation chamber 40 is carried into the radiation shielding container 32 through the opening 36A suspended and opened by the overhead crane 50. Furthermore, the isolation chamber 40 moves along the bottom of the radiation shielding container 32 toward the reactor well 25 and is stopped near the projection 57 formed at the bottom of the water channel connecting the DSP 26 and the reactor well 25. . The punch 57 (e.g., a wire saw) 41 is used to cut the projection 57 without damaging the water filled shielding bag 48 covering the containment head 18. A plurality of blocks (not shown) of the cut projections 57 are accommodated in a space 40D in the isolation chamber 40. The isolation chamber 40 containing these blocks is carried into the isolation house 49 through the opening 36A and transported to the upper floor of the operation floor 24 outside the isolation house 49 and to the ground via the opening 36A. . As shown in FIG. 26, a flat bottom surface 57A is formed on the portion of the water channel where the protrusion 57 has been removed.

  The removal of the projecting portion 57 facilitates installation of the loading / unloading air lock 89 described later (see FIG. 31) without being disturbed by the projecting portion 57. For this reason, using the carry-in / out air lock 89, the carry-out route of the reactor internals removed in the reactor pressure vessel 3 into the radiation shielding container 32 can be easily secured.

  A new side wall of the radiation shielding container 32 is installed (step S8C). There are two doors 64A, 64B that move between the work house 49 and the opening to form an opening 36B between the radiation shielding container 32 and the reactor well 25. Further, the opening 60A is also formed in the separation wall 60 which divides the work house 49 described later by the two doors. The two doors 64A and 64B are set at the position where the throttle plug is removed, and are located at a discontinuous portion which is a boundary between the circular reactor well and the rectangular device temporary placement pool 26, and the door 64A and the door The width dimensions of 64B are different. The door 64A has the width of the isolated house 49, but the door 64B corresponds to the throttle plug installation width of the equipment temporary storage pool. As for the installation of this size discontinuous portion, the removal of the throttle plug as described above facilitates the installation of the two doors 64A and 64B serving as the boundary surface partition. In FIG. 25, the door 64B is moved to the uppermost position, and the door 64A is moved close to the height of the radiation shielding plate 33 to form the opening 36B. This mechanism has the advantage of being able to form the openings necessary for the operation to be performed. The doors 64A and 64B are sealed so that radioactive materials do not move between the rooms due to their movement.

  The overhead crane installed in the isolation house is removed, and two overhead cranes and isolation walls are newly installed in the isolation house (step S8D). The overhead crane 50 installed in the isolated house 49 is removed, and guide rails 51A and 51B are newly installed in the isolated house 49 near the ceiling of the isolated house 49. Then, the overhead cranes 50A and 50B are installed on the guide rails 51A and 51B (see FIG. 26). A traveling crane carried into the isolated house 49 is used for removing the overhead crane 50 and installing the overhead cranes 51A and 51B. After the overhead cranes 50A and 50B are installed, the separation wall 60 having the opening 60A formed therein and to which the door for opening and closing the opening 60A is movably attached is carried into the isolated house 49 and the radiation shielding container 32 is installed. Standing near the end on the side of the reactor well 25 and attached to the inner surface of the isolated house 49 by welding (see FIG. 26).

  By the attachment of the isolation wall 60, two spaces 53A and 53B are formed in the isolation house 49. An overhead crane 50A and a guide rail 51A are disposed in a space 53A formed immediately above the reactor well 25, and an overhead crane 50B and a guide rail 51B are disposed in a space 53B formed immediately above the radiation shielding container 32. Is placed. A gripper 52A is attached to the wire 56A attached to the overhead crane 50A, and a gripper 52B is attached to the wire 56B attached to the overhead crane 50B. The openable and closable isolation sheet 62 attached to the inner surface of the isolation house 49 is disposed closer to the space 53 </ b> B than the door 61. A plate-like floor member 58 which forms the bottom of the space 53A is attached to the lower end of the isolated house 49. In the floor member 58, an opening 58A of the same size as the inner diameter of the reactor well 25 is formed.

  A second radiation shield is installed (step S9). A radiation shielding body (second radiation shielding body) 59 which doubles as a platform can be removed on the stepped top of the reactor well wall surface after removing the throttle plug 29A and throttle plug 29B top using the overhead crane 50A. (See FIG. 26). The platform 59 with the radioactive shield has a rail (not shown) moving in the circumferential direction on the lower surface, a drive carriage (not shown), and a suspension (not shown) on the lower surface of the drive carriage. By setting various work devices (for example, a first muscle robot and 204 to be described later, etc.) to the suspension part from the placement pool side, subsequent cutting, handling work, etc. in the reactor well are enabled. In addition, the central portion has a removable double circle of an inner circle and an outer circle, and when conducting a survey in the reactor pressure vessel to be described later, for passing a drill having a through hole in the pressure vessel head When removing the inner circle and setting up the isolation vessel for removing the equipment in the reactor pressure vessel, remove the outer circle and use it for passage of the isolation vessel. A retractable isolation sheet 54 stored in the isolation film storage container 73 is disposed to cover the second radiation shielding platform 59 installed so as to cover the reactor well 25 after installation. The second radiation shield and dual use platform 59 is transported by the crawler crane on the operation floor 24 outside the isolated house 49 and is further transferred into the space 53A via the space 53B. The second radiation shield dual use platform 59 is suspended by the overhead crane 50A and placed on the top of the reactor well wall through the opening of the opening and closing isolation sheet 54, and the floor drives by the above-described drive device. It is installed to cover the opening 58A of the member 58.

  The device in the reactor well is removed and carried out (step S10). The removal and unloading of equipment disposed in the reactor well 25, for example, the containment head 18 attached to the upper end of the reactor containment vessel 17 and disposed in the reactor well 25, is shown in FIGS. This will be described using First, in order to facilitate removal of the equipment in the reactor well, the shielding bag 48 is carried out (see FIG. 26).

  The carrying out of the shielding bag 48 is performed in the reverse step of the carrying in of the shielding bag 48 described in step S5 except for the carrying in and out of the shielding body conveying device 47. In the shielding body transfer device 47, another separation chamber 40 in which the shielding body transfer device 47 and the folded shielding bag 48 are accommodated is inserted into the radiation shielding container 32 through the opening 36A as in the process of step S2. After being carried in, the door 34 is closed. The isolation chamber 40 contacts and stops the projection on the reactor well 25 side of the radiation shielding container 32. Similar to the handrail removal device 45, the shield transfer device 47 has a slide mechanism 45B attached to the upper end portion of the support member 42, a telescopic tube 45A, and a working arm 45C. A gripper 47A is attached to the tip of the working arm 45C.

  The working arm 45 C and the gripping tool 47 A gripping the shielding bag 48 are inserted into the reactor well 25. Then, a water supply hose (not shown) installed along the telescopic tube 45A and the working arm 45C extends and is connected to the one-touch coupler with the non-return function provided on the shielding bag 48 released. Water is drained. Thereafter, the telescopic tube 45A and the working arm 45C are contracted to recover the shielding bag 48. This step is sequentially performed on the left and right shielding bags 48, and then the shielding bags 48 are carried out of the radiation shielding container 32 from the opening 36A.

Next, the removal of the storage container head 18 and the unloading step will be described with reference to FIG. First, the first muscle robot 204 which is an articulated manipulator is loaded into the reactor well 25.
The first muscle robot is carried into the space 37 in the radiation shielding container 32 by the isolation chamber 40 in the same manner as the shielding body transfer device 47. In the isolation chamber 40, the first muscle robot 204 is suspended on the tip side having a level difference by the amount of elevation, and the first muscle robot 204 is carried into the reactor well 25, moved up and down, and fitted to the turning portion 79A. It has an arm. The pivoting portion 79A has a function of circling the back surface of the second radiation shield on the reactor well 25 side.

  The first muscle robot 204 has a telescopic unit that changes its arm length, a posture unit that changes the tip posture three-dimensionally, a camera (not shown) provided at the tip of the posture unit, and a cutter as a work effecter And. Also, the first muscle robot 204 has a mounting portion 204A that engages with the pivoting portion 79A, and a wire can be attached to the mounting portion 204A in a variable length, and a gripping tool 72B is mounted to the tip of the wire Be

  According to this configuration, the operator uses the camera monitor to grasp a convex portion such as a hook provided on the storage container head 18 by the operator to operate the first muscle robot 204, and any range including the range including the hook The range can be cut.

  After installing the first muscle robot 204 in the reactor well 25, the isolation chamber 40 in which the cutting and collecting apparatus 70 is housed, and the loading and unloading chamber 75 in which the storage container 206 capable of storing shredded cutting pieces is carried in and out Are sequentially suspended by the crawler crane and carried into the space 37 of the radiation shielding container 32 through the opening 36A (see FIG. 27).

  The cutting and collecting apparatus 70 includes a slide type mount 205 for collecting cut pieces of the storage container head cut to a predetermined size by the first muscle robot 204 and a second muscle robot 208 for further cutting the collected cut pieces. And a horizontal movement unit 209 which moves the second muscle robot left and right so as to be efficiently shredded and collected in the storage container 206.

The slide type mount 205 has a slide portion 205A which can be carried in and out of the reactor well 25 through the opening 70B provided at the position of the cutting and collecting device 70 corresponding to the opening 36B of the radiation shielding container 32.
The second muscle robot 208 is provided at the tip of each of the posture units, and the expansion and contraction unit provided on the root side to change its arm length, two three-dimensionally postureable posture units fixed to the expansion and contraction unit (Not shown) as a work effect device and a cutter.

  The isolation chamber 40 and the loading / unloading chamber 75 have openable and closable openings (not shown) provided at their adjacent portions, for example, the storage container 206 has moving means 206A movable between the both through the openings. Furthermore, the loading / unloading chamber 75 has an openable / closable opening 75A at a position corresponding to the opening 36A of the radiation shielding container 32.

  With these configurations, the cutting and collecting device 70 can further shred the cut piece 18A of the PCV head 18 collected by the slide portion 205A, and can hold the small pieces in the storage container 206. Then, the small pieces stored in the storage container 206 are transferred to the space 53B of the isolated house 49 by the overhead crane 50B through the opening 75A and the opening 36, and further transferred onto the operation floor 24 outside the isolated house 49. , Be dropped to the ground.

  Although the above procedure shows that the isolation house is placed on the operation floor after removing the shield plug and then the containment head 18 is removed, the containment head 18 may be removed before removing the shield plug. At this time, the apparatus has the same structure as the decontamination apparatus 46 in the reactor well shown in FIG. 14 and has a slide mechanism 45B attached to the upper end of the support member 42, a telescopic tube 45A and a work arm 45C. Using this apparatus, the storage container head 18 is finely cut, and the cut pieces are drawn into the isolation chamber 40 in the same manner as the handrail removal of the storage container head 18 and stored in the storage container in the isolation chamber 40 and carried out. Do. The unloading of the storage container may be performed by connecting a loading / unloading chamber 75 shown in FIG. This method is the same as the heat insulating material described later.

  As a method for carrying out the storage container 206, another method for preventing leakage of radioactive substances via the water storage chamber 301 will be described with reference to FIG. The water storage chamber 301 has a partition at the center, and the partition has a passage on the lower surface through which the storage container 206 can pass. The water surface is located above the passage on the lower surface. The water storage chamber 301 has an inlet 302 and an outlet 303 for the storage container 206. A lifting machine (not shown) is attached above the inlet 302, and the storage container 206 carried in from the inlet 302 is It is possible to install it on the moving means 206A provided below the water surface. The inlet 302 of the water storage chamber 301 is connected to the outlet of the storage container 206 of the isolation chamber 40 used as a shredding area, and has a sealing structure in the meantime. The outlet 303 of the water storage chamber 301 is located on the lower surface of the opening 34 of the radiation shielding container 32 installed in the equipment temporary storage pool. Next, the procedure for carrying out the storage container 206 will be described. The storage container 206 containing shredded small pieces in the isolation chamber 40 is lifted by a lifting machine (not shown) disposed along the rail of the second muscle robot 208 located at the upper end of the isolation chamber 40 , Delivered to a lifting machine (not shown) on the water storage chamber 301 side. After that, it is suspended below the water surface, and moves to the outlet 303 side by passing through a passage provided on the moving means 206A provided on the lower surface and provided on the surface. An overhead crane 50B from the isolated house is disposed above the outlet 303, and is lifted and carried out on the water surface by lifting. As a result, when the storage container 206 is carried out, the radioactive substance present in the isolation chamber 75 can be prevented from diffusing on the water surface, and can be prevented from flowing out from the discharge port 303 of the water storage chamber 301 into the radioactive shielding container 32.

  Next, the heat insulating material 30 is removed and carried out (FIG. 28). The details thereof are the same as the removal and the removal of the PCV head 18, and can be described in other words by replacing the storage container head 18 with the heat insulating material 30, so the detailed description will be omitted. 4A is a cut piece of the heat insulating material 30.

  The above-mentioned storage container head 18 and the heat insulating material 30 were taken out and carried out after the second radiation shield 59 was provided. On the other hand, the approach of dismantling may be performed while maintaining the shield plug 28 by performing the approach from inside the radiation shielding container 32 or by configuring the first muscle robot more compactly. Thereafter, a second radiation shield 59 may be installed for further work. In addition, you may use similarly the water storage chamber 301 mentioned above instead of the carrying in / out chamber 75 as a carrying out method of the storage container 206. FIG.

  From the above, the container head 18 and the heat insulating material 30 are contaminants, and in particular, the heat insulating material 30 has a complicated shape, so decontamination is difficult and has a high radiation equivalent rate. Raising these structures from the reactor well onto the operating floor significantly degrades the operating environment on the operating floor and thus interferes with other parallel operations. On the other hand, the equipment in the reactor well is cut out and carried out in the reactor well and the equipment temporary storage pool side, stored and taken out in the discharge container with shielding, an increase in radiation equivalent rate on the operation floor and It is possible to prevent the spread of radioactive dust and maintain a working environment accessible to workers.

By the above, removal and unloading of the device in the reactor well in step S10 are completed.
In FIG. 27, in addition to the step S10 of removing the equipment in the reactor well and carrying it out, the used fuel rods 203 are removed from the fuel storage pool 27 by the fuel extraction device 201 to, for example, a shared pool outside the reactor building 23. The pool fuel removal step (step SF1) to be transferred is described. The spent fuel rods 203 are taken out of the fuel rack 202 by the telescopic tube 201B of the fuel takeout device 201 and transferred to the common pool by the moving function of the main body 201A of the fuel takeout device.

  The pool fuel removal process is performed not only at the time of removal and removal of the containment vessel head 18 but also for a long time from step S1 shown in FIG. Therefore, in the present embodiment, the entire operation time can be significantly reduced as compared with the conventional method in which both operations are sequentially performed.

  Next, the removal of the baffle plate 76 and the attachment of the pressure vessel support and the radiation shielding plate 79 are performed (step S11). This process is carried out in parallel with the containment vessel head and the heat insulating material extraction when the pool fuel extraction operation is not completed. The reason for removing the baffle plate 76 is because the baffle plate 76 does not have the ability to support the pressure vessel 4. In consideration of work in the pressure vessel 4 in the future, a support beam member 80 having a high support capacity is laid. Step S11 will be described with reference to FIG.

In the process of step S11, the cutting and recovering apparatus 70, the loading and unloading chamber 75, the storage container 206, and the like in the isolation chamber 40 used for removing and unloading the equipment in the reactor well of step S10 are used.
As shown in FIG. 29, the radiation shielding plate 79 and the support beam member 80 are placed on the slide type mount 205 in the isolation chamber 40 via the loading and unloading chamber 75. Thereafter, the door 64 in the isolation chamber 40 is opened, and the slide portion 205A is carried into the nuclear well 25. The radiation shielding plate 79 is gripped by the holding tool 72B and moved to above the baffle plate 76 in the reactor well 25. The radiation shielding plate 79 is then placed on the baffle plate 76. The support beam 80 in the isolation chamber 40 is likewise gripped by the grippers 72B and placed on the baffle plate 76 as well. However, nothing is placed on one baffle plate 76, and only the radiation shielding plate 79 is placed on the adjacent baffle plate 76.

  The baffle plate 76 on which nothing is placed is gripped by the gripper 72B and removed. Each removed baffle plate 76 is carried out through the isolation chamber 40 and the loading and unloading chamber 75. Next, the radiation shielding plate 79 on the adjacent baffle plate 76 is held by the gripper 72B and lowered to the region between the reactor pressure vessel 3 and the reactor containment vessel 17, and the reactor pressure vessel 3 and the reactor pressure vessel 3 It is attached to the reactor containment vessel 17. Next, the support beam member 80 installed on the baffle plate 76 adjacent to the baffle plate 76 which has not been placed is gripped by the holding tool 72B and lowered, and the reactor above the radiation shielding plate 79 The pressure vessel 3 and the living body shield 100 are installed. The state at this time is the radiation shielding plate 79 and the support beam member 80 existing on the right side of FIG. The above process is performed on the baffle plate 76 which has not been placed in sequence. Finally, the radiation shielding plate 79 and the supporting beam member 80 lacking are procured from the slide portion 205A. In addition, you may use the water storage chamber 301 mentioned above instead of the carrying in / out chamber 75 similarly as a carrying out method of the storage containers 206 grade | etc., Which accommodate waste materials, such as a baffle plate removed.

  The plurality of radiation shielding plates 79 disposed in the region between the reactor pressure vessel 3 and the reactor containment vessel 17 and attached to the reactor pressure vessel 3 and the reactor containment vessel 17 are the reactor pressure vessel 3 and the reactor. It seals the region between containment vessels 17 and shields the radiation from reactor containment vessel 17 toward reactor well 25 and prevents the rise of radioactive dust from reactor containment vessel 17 toward reactor well 25. Do. The plurality of support beam members 80 disposed in the region between the reactor pressure vessel 3 and the biological shield 100 and attached to the reactor pressure vessel 3 and the biological shield 100 are the reactor pressure vessel 3 and the biological shield 100. And seal the reactor pressure vessel 3 from the biological shield 100. This is to prevent the reactor pressure vessel 3 from falling downward as a countermeasure in the case where there is a problem in the strength of the concrete support of the pedestal 15 supporting the reactor pressure vessel 3.

  The inside of the reactor containment vessel is inspected (step S11.5). This process is carried out in parallel with the containment vessel head and the heat insulating material extraction when the pool fuel extraction operation is not completed. The investigation process for inspecting the inside of the reactor containment vessel will be described with reference to FIG. In this investigation step, a through hole is opened in the pressure vessel head 4, and a camera is inserted from there to investigate the internal condition of the reactor containment vessel. For this purpose, first, the head inspection jig 210 incorporating the drill 210A is transferred to the isolation chamber 40 through the loading / unloading chamber 75, and is loaded into the reactor well 25 using the slide portion 205A of the slide type support 205. Thereafter, the first muscle robot 204 and the grasping tool 72B are used to place the head on the pressure vessel head 4. The motor 210B is driven to rotate the drill tool 210A built in the inner cylinder on the tip side of the head inspection jig 210 while stretching it, and the through hole 4B is opened in the pressure vessel head 4 as shown in FIG.

  Thereafter, the head inspection jig 210 is once returned to the isolated house 49, a camera is newly attached in place of the drill tool 210A, and installed again on the head of the pressure vessel head 4 in the same manner as in the drill tool. The motor 210B is driven to insert a camera into the pressure vessel through the through hole 4B, and the state of the inside of the nuclear pressure vessel 3, particularly, in the vicinity of the pressure vessel head 4 and the steam dryer 12 is grasped. The grasping of the state of the steam dryer 12 can be reflected in the removal operation of the steam dryer 12.

  Further, if the condition of the steam dryer 12 is firm, the through hole is similarly formed in the steam dryer 12, and the condition of the steam separator 11 is grasped in the same manner to take out the steam separator. It can be reflected.

  Another method of the investigation step of inspecting the inside of the reactor containment vessel will be described with reference to FIG. In this investigation step, a through hole is opened in the pressure vessel head 4, and a camera is inserted from there to investigate the internal condition of the reactor containment vessel. For this purpose, first, the head inspection jig 210 incorporating the drill 210A is housed in the inspection container 310 having a shield and set on the upper surface of the platform 59 serving as the second radiation shield through the isolation house 49. As a procedure at that time, the investigation container 310 is once installed on the upper surface of the isolation film 54, and after covering the investigation container 310 from below, the investigation container 310 is set on the lower surface of the isolation film 54 by melting and welding on the upper surface of the investigation container 310. After that, the inner circular portion located at the center of the second radiation shielding platform 59 is removed by a working device (not shown) provided in the investigation container 310, and the second radiation shielding platform is mounted on the lower surface of the investigation device 310. Form a passage for passing a drill through 59. The motor 210B is driven to rotate the drill tool 210A built in the inner cylinder on the tip end side of the head inspection jig 210 while stretching it, and the through hole 4B is opened in the pressure vessel head 4 as shown in FIG.

Thereafter, the head inspection jig 210 is once returned to the inspection container 310, and a camera is newly attached instead of the drill tool 210A, and installed again on the head of the pressure vessel head 4 in the same manner as the drill tool. The motor 210B is driven to insert a camera into the pressure vessel through the through hole 4B, and the state of the inside of the nuclear pressure vessel 3, particularly, the vicinity of the pressure vessel head 4 and the steam dryer 12 is grasped. The grasping of the state of the steam dryer 12 can be reflected in the removal operation of the steam dryer 12.
As a survey method, next, in the state of the isolation container described in FIG. 31, the head survey jig is suspended by the lifting device 83, a through hole is provided in the pressure vessel head 4, and the inside of the pressure vessel head 4 is surveyed You may

  An isolation container is installed (step S12). After the process of step S11 is completed, the isolation container 81 is arranged from the reactor well 25 to the space 53A (see FIG. 31). The configuration of the isolation container 81 will be described with reference to FIG. The isolation container 81 has an upper cylindrical member 81A, an intermediate cylindrical member 81B and a lower cylindrical member 81C, and the upper end of the upper cylindrical member 81A is closed by a cover member 81D which is a disk. A lower cylindrical member 81 C having a shielding bag 86 installed therein is installed on the support beam member 80 in the reactor well 25. An intermediate cylindrical member 81B in which the shielding bag 85 is installed is placed at the upper end of the lower cylindrical member 81C and is coupled to the lower cylindrical member 81C. An upper cylindrical member 81A sealed with a cover member 81D, in which the holding member 82 and the support member 82A are disposed, is placed on the upper end of the intermediate cylindrical member 81B and coupled to the intermediate cylindrical member 81B. A radiation shielding plate 91 having an opening through which the intermediate cylindrical member 81B is formed is disposed on the floor member 58. The radiation shielding plate 91 is an opening 58A formed in the floor member 58 except for the portion of the intermediate cylindrical member 81B. Is covered. The middle portion of the second radiation shield 59 has a diameter slightly larger than the outer diameter of the opening 58A.

  Further, a carry-in / out air lock 89 is disposed in the reactor well 25, and one end of the carry-in / out air lock 89 is attached to the side wall 63 of the radiation shielding container 32. An open / close door 89A is attached to one end of the carry-in / out air lock 89 on the radiation shielding container 32 side. The other end of the carry-in / out air lock 89 is attached to the lower cylindrical member 81C. An open / close door 89B is attached to the other end of the carry-in / out air lock 89 on the lower cylindrical member 81C side. The space 89C in the carry-in / out air lock 89 is communicated with the radiation shielding container 32 by opening the open / close door 89A, and communicated with the lower cylindrical member 81C by opening the open / close door 89B.

  A carry-in / out air lock 90 is disposed on the radiation shielding plate 91 in the space 53A, and one end of the carry-in / out air lock 90 is attached to the intermediate cylindrical member 81B. An open / close door 90A is attached to one end of the carry-in / out air lock 90 on the side of the intermediate cylindrical member 81B. At the other end of the carry-in / out air lock 90, an open / close door 89B is attached. The space 90C in the carry-in / out air lock 90 is communicated with the inside of the intermediate cylindrical member 81B by opening the open / close door 90A, and is communicated with the space 53A in the isolated house 49 by opening the open / close door 90B.

  A sprinkler (not shown) is installed near the top of the inner surface of the carry-in / out air lock 89, and a sprinkler (not shown) is installed near the top of the inner surface of the carry-in / out air lock 90. Further, an air exchange device (not shown) for exchanging air in the space 89C is installed in the carry-in / out air lock 89, and an air exchange device (not shown) for exchanging air in the space 90C in the carry-in / out air lock 90 as well. Will be installed.

  The upper cylindrical member 81A, the middle cylindrical member 81B and the lower cylindrical member 81C sealed by the cover member 81D are joined as described above, and the opening / closing door 89A of the carry-out air lock 89 and the open / close door 90A of the carry-out air lock 90 Are respectively attached, a sealed space 93 is formed in the isolated container 81 formed by combining the upper cylindrical member 81A, the intermediate cylindrical member 81B and the lower cylindrical member 81C.

  Each of the intermediate cylindrical member 81B and the lower cylindrical member 81C is carried into the reactor well 25 and the space 53A in a state where water is not filled in the shielding bags 85 and 86. The intermediate cylindrical member 81B and the lower cylindrical member 81C are lightened because the shielding bags 85 and 86 are not filled with water, and the intermediate cylindrical member 81B and the lower cylindrical member 81C can be easily carried into the reactor well 25 and the space 53A. It is. Water supply into the shielding bags 85 and 86 is carried out using a water supply hose connected to a water supply system existing outside the isolation house 49 after the isolation container 81 is assembled in the reactor well 25 and the space 53A. Be done. Each of the shielding bags 85 and 86 filled with water inside is a radiation shielding body. The shielding bag 85 filled with water inside is arranged so as to face the opening / closing door 90A of the carry-in / out air lock 90 in the isolation container 81, and the shielding bag 86 filled with water inside is carried out in the isolation container 81 The pressure vessel head 4 is disposed to face the open / close door 89B of the inlet air lock 89 so as to face the same. Similar to the shielding bag 48, through holes 85A and 86A are respectively formed in the shielding bags 85 and 86 filled with water, respectively. The through hole 85A is surrounded by the members of the shielding bag 85, and the water in the shielding bag 85 does not flow into the through hole 85A. The through hole 85A is filled with water and sealed by the expanded shielding bag 85. The through hole 86A of the shielding bag 86 has a similar structure.

  A rod-like support member 82A is horizontally disposed and attached to the inner surface of the upper cylindrical member 81A. The holding member 82 is installed on the support member 82A. An isolation sheet 84 is attached to the lower end of the upper cylindrical member 81A to separate the space in the upper cylindrical member 81A from the space in the intermediate cylindrical member 81B. A lifting device (for example, a hoist) 83 is held by the holding member 82 by the wire 128. The wire 128 penetrates the isolation sheet 84 and is sealed between the wire 128 and the isolation sheet 84 in order to maintain air tightness. This isolation sheet is folded in a bellows shape, and has a structure that can expand and contract in accordance with the descent and rise of the wire.

  Remove the pressure vessel head (step S13). Since the pressure vessel head 4 is attached to the flange of the reactor pressure vessel 3 by a plurality of bolts, in order to remove the pressure vessel head 4 from the reactor pressure vessel 3 it is necessary to remove those bolts. An outline of the removal of those bolts will be described. A stud bolt tensioner is used to remove these bolts. Although not shown, an isolation chamber 40 containing a stator bolt tensioner, a pair of half guide rails and a manipulator device (not shown) opens and closes through an opening 36A and a space 37 in the radiation shielding container 32. By opening the door 89A, it is carried into the space 89C in the carry-in / out air lock 89. At this time, the open / close door 89B is closed. The manipulator device has substantially the same configuration as the shield transfer device 47 used in step S5. The manipulator device has a slide mechanism 45B attached to the upper end of the support member 42, a telescopic tube 45A, and an articulated work arm 45C. A gripper 47A is attached to the tip of the working arm 45C.

  After gripping one of the guide rails in the separation chamber 40 with the gripping tool 47A, the open / close door 89B is opened, and the slide mechanism 45B and the telescopic tube 45A are covered with water in the lower cylindrical member 81C. It is moved downward of the The working arm 45C is bent and extended, and the half guide rail gripped by the grip 47A is placed below the shielding bag 86 and above the flange of the pressure vessel head 4 and the inner surface of the lower cylindrical member 81C and the pressure vessel It is arranged between the outer surfaces of the head 4 and at a position 180 ° opposite to the open / close door 89B. A plurality of support members are attached to the lower surface of the half of the guide rails, and the guide rails are supported on the support beam members 80 by these support members. Another half guide rail is also disposed by the manipulator device between the inner surface of the lower cylindrical member 81C and the outer surface of the pressure vessel head 4 below the shielding bag 86 and at a position on the opening / closing door 89B side. The two half guide rails are connected to one another. By means of the manipulator device, the guide rail is fitted with a moving device having a holding part of a stat bolt tensioner, to which a stat bolt tensioner is attached. By driving the moving device, the stat bolt tensioner is transferred above the bolt connecting the pressure vessel head 4 and the reactor pressure vessel 3 and the bolt is removed by the stat bolt tensioner. Thus, the bolts connecting the pressure vessel head 4 and the reactor pressure vessel 3 are sequentially removed. Then, the connection between the pressure vessel head 4 and the reactor pressure vessel 3 is released. Each removed bolt is collected into the isolation chamber 40 by the manipulator device. Thereafter, the slide mechanism 45B and the telescopic tube 45A are contracted, and the grasping tool 47A is also accommodated in the isolation chamber 40.

  The open / close door 89B is closed, and the door provided in the isolation chamber 40 is also closed. The air exchange device of the carry in / out air lock 89 discharges the air in the space 89C to the outside and supplies the clean air in the space 89C. The air exchange device includes a purification device, and radioactive substances contained in the air exhausted from the space 89C are removed by the purification device. Water is applied to the isolation chamber 40 from the water spray device in the carry-in / out air lock 90 to wash away the attached radioactive substance. The water is discharged to a drainage device provided in the carry-in / out air lock 89. Then, the isolation chamber 40 is transferred to the space 37 in the radiation shielding container 32 by opening the opening and closing door 89A, and after the opening and closing door 89A is closed, it is transported to the outside of the isolation house 49 through the opening 36A and the like.

  While removing the bolt connecting the pressure vessel head 4 and the reactor pressure vessel 3, a grip (not shown) is attached to the tip of the wire 87 wound around the lifting device 83. The wire 87 reaches near the top of the pressure vessel head 4 through the through-hole 85A of the water-filled shielding bag 85 and the through-hole 86A of the water-filled shielding bag 86, and is attached to the wire 87 A tool grips a hanger 88 attached to the top of the pressure vessel head 4.

  After the pressure vessel head 4 and the reactor pressure vessel 3 are released from connection, the pressure vessel head 4 is raised to be water-filled shielding bag 86 by driving the lifting device 83 to wind the wire 87. (FIG. 32). As the pressure vessel head 4 ascends in the through hole 86A, water present above the pressure vessel head 4 in the shielding bag 86 moves downward in the shielding bag 86 relative to the pressure vessel head 4. Therefore, the pressure vessel head 4 can easily ascend in the through hole 86A of the water-filled shielding bag 86, and the position of the lower end of the shielding bag 86 is lowered to near the upper end of the steam dryer 12. The shielding bag 86 filled with water shields the radiation from inside the reactor pressure vessel 3 below the steam dryer 12.

  When the pressure vessel head 4 is filled with water in the sealed space 93 and is filled with the shielding bag 85 and the water and ascends between the shielding bag 86, the decontamination of the inner surface (lower surface) of the pressure vessel head 4 is a decontamination apparatus 71 (see FIG. 33). The decontamination apparatus 71 has a telescopic tube and a working arm like the shield conveyance device 47, and has an injection nozzle at its tip instead of the gripping tool 47A (see FIG. 16). Similar to the shield transfer device 47, the isolation chamber 40 containing the decontamination apparatus 71 is carried into the radiation shield container 32 through the opening 36A, and the open / close door 89A is opened to carry out the inside of the carry-out air lock 89. Is moved into the space 89C of The openable door 89A is closed, and the upper end portion which is a part of the openable door 89B is opened. In the decontamination apparatus 71, a telescopic tube is inserted between the pressure vessel head 4 and the shielding bag 86 in the space 93. The operation arm is operated to cause the injection nozzle to face the inner surface of the pressure vessel head 4, and water is injected from the injection nozzle. While the water is being jetted from the jet nozzle, the telescopic tube and the working arm are operated to decontaminate the inner surface of the pressure vessel head 4 (see FIG. 33). Water falling on the inner surface of the pressure vessel head 4 is received by a washing water receiver (not shown) attached to the working arm, and collected in the drainage tank in the isolation chamber 40 as described above. The decontamination of the pressure vessel head 4 may be performed on the lower surface of the shielding bag 86. In this case, when the lower surface of the pressure vessel head 4 is pulled up to a position above the upper end of the dryer 12 in consideration of the space where the decontamination apparatus 71 can be inserted, the work arm is set on the lower surface and decontamination is performed by the injection nozzle Do. Thereafter, it passes through the shielding bag 86 and is pulled up. After the decontamination of the inner surface of the pressure vessel head 4 is completed, the telescopic tube, the working arm and the injection nozzle are accommodated in the isolation chamber 40, and the open / close door 89B is completely closed. The isolation chamber 40 is transported from the space 89C in the transfer air lock 89 to the ground through the opening 36A.

  A part of the water in the shielding bag 85 is discharged to reduce the thickness of the shielding bag 85 in a state where water is present inside. The lifting device 83 is driven to raise the pressure vessel head 4 to a position facing the open / close door 90A (see FIG. 34). Thereafter, the openable door 90A is opened, the pressure vessel head 4 is transferred into the space 89C, and the openable door 89A is closed. By opening the openable door 90A, there is a possibility that the radioactive substance may flow into the space 89C. For this reason, the air in the space 90C is discharged to the outside by the air exchange device of the carry-in / out air lock 90, and the external clean air is supplied into the space 90C. The air exchange device includes a purification device, and radioactive substances contained in the air exhausted from the space 90C are removed by the purification device. The pressure vessel head 4 is decontaminated before being carried into the space 90C, but after being carried into the space 90C, water is applied to the pressure vessel head 4 from the water sprinkler in the carry-in / out air lock 90 again Wash away any radioactive material This water is drained to the drainage device provided in the carry-in / out air lock 90. Then, the open / close door 90B is opened to transfer the pressure vessel head 4 into the space 53A, and the pressure vessel head 4 is stored at a predetermined storage location. The openable door 90B is closed.

  In the present embodiment, the isolation vessel 81 is disposed so as to cover the pressure vessel head 4 in the space 53A in the reactor well 25 and the isolation house 49, and opening of the reactor by removing the pressure vessel head 4 has a small internal volume. Even if radioactive material is released from inside the reactor pressure vessel 3 from which the pressure vessel head 4 has been removed because it is carried out in the isolation vessel 81, the area contaminated with this radioactive substance is limited within the isolation vessel 81, It is possible to prevent the inside of the large volume reactor well 25 and the isolation house 49 from being contaminated by the radioactive material.

  Since the water-filled shielding bags 85 and 86 are disposed in the isolation container 81, the radiation emitted from the reactor pressure vessel 3 can be shielded by the shielding bags 85 and 86. For this reason, the dose in the isolation house 49, for example, the dose in the space 53A can be suppressed to a low value without being affected by the radiation from the reactor pressure vessel 3. It is possible to significantly reduce the exposure of the worker who works in the space 53A.

  The carrying out of the equipment (for example, pressure vessel head 4 etc.) in the separating container 81 out of the separating container 81 and the loading of the articles into the separating container 81 are performed through the carrying in / out air locks 89 and 90. It is possible to prevent the release of air containing radioactive substances in 81 to the external environment. In particular, each of the carry-in / out air locks 89 and 90 is provided with a water spray device and an air exchange device, so that it is possible to prevent the radioactive material from being released to the external environment.

  As another method of taking out the pressure vessel head 4, there is also a method of shredding before setting the isolation vessel 81 in the same manner as the removal of the containment vessel head 18. FIG. 44 shows a state in which the pressure vessel head 4 is shredded. The details thereof are the same as the removal and unloading of the PCV head 18, and the storage container head 18 can be described in other words as the pressure container head 4, and thus the detailed description will be omitted. 4A is a cut piece of the pressure vessel head 4. In addition, you may use similarly the water storage chamber 301 mentioned above instead of the carrying in / out chamber 75 as a carrying out method of the storage container 206. FIG.

  Thus, the reactor opening operation in the method of opening the reactor pressure vessel is completed, and all the steps of the method of opening the reactor pressure vessel are completed.

  The removal of the steam dryer and the air-water separator will be described. After the removal of the pressure vessel head 4 (step S13) is completed, the removal of the steam dryer and the air-water separator is performed (step S14). First, taking out the steam dryer 12 in the case where the steam dryer 12 can be easily removed from the reactor pressure vessel 3 will be described below with reference to FIGS.

  Although not illustrated in FIG. 35, the manipulator device used in step S13 and the isolation chamber 40 containing the lifting balance 92 are carried into the space 37 in the radiation shielding container 32 through the opening 36A, and further opened and closed. The door 89A is opened and transferred into the carry-in / out air lock 89. After the isolation chamber 40 is transferred into the transfer air lock 89, the open / close door 89A is closed and the open / close door 89B is opened. The lifting balance 92 in the isolation chamber 40 is gripped by the gripper 47A of the manipulator device, and then the slide mechanism 45B and the telescopic tube 45A are extended to load the lifting balance 92 into the space 93 in the isolation container 81. After the lifting balance 92 is placed on the steam dryer 12, the gripping tool 47A is released from the lifting balance 92, and the lifting tool of the lifting balance 92 is gripped and lifted by the grip 47A. A gripper attached to the wire 87 connected to the lifting device 83 grips the lifting device of the lifting balance 92.

  After the working arm 45C and the grasping tool 47A of the manipulator device are stored in the isolation chamber 40, the open / close door 89B is closed, the air in the space 89C is replaced with clean air by the air exchange device, and the loading / unloading air lock The water sprayed from the water sprayer within 89 is hung on the outer surface of the isolation chamber 40 to wash away the adhering radionuclide. The open / close door 89A is opened, the isolation chamber 40 is transferred to the space 37, and the open / close door 39A is closed. The isolation chamber 40 is transported to the ground through the opening 36A.

  After the steam dryer 12 is removed from the reactor pressure vessel 3, the lifting device 83 is driven to wind the wire 87 (see FIG. 35). Furthermore, when the wire 87 is wound up, the steam dryer 12 rises. When the lower end of the steam dryer 12 rises to the position of the carry-in / out air lock 89, the rise of the steam dryer 12 is stopped and the open / close doors 89A and 89B are opened. The slide type carriage 92 which has been carried into the radiation shielding container 32 and placed on the bottom surface of the radiation shielding container 32 is moved through the inside of the carry-in / out air lock 89 into the lower cylindrical member 81C. By driving the lifting device 83 to rewind the wire 87, the steam dryer 12 is placed on the sliding carriage 92 in the lower cylindrical member 81C (see FIG. 36). Since the openable and closable doors 89A and 89B are open, the radionuclide in the lower cylindrical member 81C may diffuse to the carry-in / out air lock 89 and the radiation shielding container 32.

  By moving the slide type carriage 92, the steam dryer 12 is transferred through the inside of the transfer air lock 89 to the space 37 in the radiation shielding container 32 (see FIG. 36). The openable doors 89A and 89B are closed. As described above, the air in the space 89C in the carry-in / out air lock 89 is replaced, and the inside of the carry-in / out air lock 89 is cleaned by watering. In the radiation shielding container 32, a water sprinkler (not shown) is installed on the lower surface of the radiation shielding plate 33, and an air changer (not shown) is installed on the radiation shielding plate 33. After the steam dryer 12 is transferred to the space 37 in the radiation shielding container 32 and the open / close doors 89A and 89B are closed, the air in the radiation shielding container 32 is replaced with clean air by the air exchange device, and the water sprinkler The jetted water cleans the steam dryer 12 and the sliding carriage 92 of the radiation shielding container 32. The steam dryer 12 and the slide type carriage 92 of the radiation shielding container 32 are transported to the ground through the opening 36A.

  The steam-water separator 11 attached to the core shroud 6 in the reactor pressure vessel 3 is also taken out of the reactor pressure vessel 3 like the steam dryer 12 and transported to the ground through the opening 36A.

As a measure after taking out the steam dryer 12, there is also a means for shredding in the space in the radioactive shielding container 32 installed in the equipment temporary storage pool. The shredding procedure of the steam dryer 12 will be described with reference to FIG.
Shredding of the steam dryer 12 is performed remotely in water to reduce radiation and prevent the diffusion of radioactive dust generated at the time of cutting. In that case, the radiation shielding container 32 disposed in the equipment temporary storage pool is remodeled before taking out the steam dryer 12. A movable submersible working arm 321 is attached to the lower surface of the radioactive shielding container 32 on the entire surface of the radioactive shielding container 32 for new shredding work. Next, after the removal air lock 89A of the radiation shielding container 32 is removed and the partition 322 is newly attached on the upper surface of the radioactive shielding container 32, a new opening / closing device 323 is attached to the upper opening. The steam dryer 12 and the steam / water separator 11 are removed from the reactor pressure vessel in the same manner as the procedure from FIG. 35, and sequentially carried in the newly modified radiation shielding vessel 32 by the drawing device 320 having a conveyor function. Do. Thereafter, the radiation shielding container 32 is filled with water and shredded in the water remotely. The shredding work is cut and handled by the underwater working arm 321 and stored in the storage container 206. The storage container 206 has moving means 206A on the lower surface, moves in a passage on the lower surface of the partition 322, and is located at the outlet. Thereafter, it is pulled up on the water surface by the overhead crane 50B and carried out. At this time, by setting the water surface height of the radiation shielding container 32 higher than the lower end of the partition 322, the dust containing radioactive material generated in the shredded area is prevented from diffusing by the partition 322, and the outlet of the radiation shielding container. Prevent spills to the side. This concept is the same as the water storage chamber 301 shown in FIG. In addition, the dust containing the radioactive substance generated at the shredding place is ventilated by a ventilation device (not shown) connected to the radiation shielding container 32 and collected by a filter (not shown). In addition, suspended particles and precipitated particles extracted into water are similarly purified by a filter-equipped water purifier (not shown) connected to the radiation shielding container 32.
Since the above-mentioned shredding work of the steam generator 12 and the air-water separator 11 is carried out in the equipment temporary storage pool, interference of work with the reactor pressure vessel side does not occur, and fuel debris extraction work is performed in parallel. Can be implemented.

  In the event that the steam dryer 12 can not be removed from the reactor pressure vessel 3 when taking out the steam dryer 12, the steam dryer 12 shown in FIG. Removal is performed. The steam dryer 12 is cut and taken out as a cut piece from the steam dryer 12. The alternative will be described with reference to FIG.

  The disassembling device 94 is carried from the space 37 in the radiation shielding container 32 into the lower cylindrical member 81C through the carrying in / out air lock 89. The door 34 of the radiation shielding container 32 is closed. The aforementioned manipulator device is used for this loading. The disassembling device 94 is suspended by the holding device of the lifting and lowering device 83 and installed on the upper flange of the reactor pressure vessel 3.

  The configuration of the disassembling device 94 will be described below. The disassembling device 94 has four columns 94B, and these columns 94B are connected by each of four horizontally arranged connecting members 94A. An articulated arm 94C provided with a cutting machine 94D at its tip and an articulated arm 94E provided with a gripping tool 94F at its tip are movably attached to a horizontally extending connecting member 94A Mounted on a moving carriage. Four columns 94 B are installed on the upper flange of the reactor pressure vessel 3.

  Further, the storage container transfer device 95 is carried from the space 37 in the radiation shielding container 32 to the space 89 C in the transfer air lock 89. The storage container transport device 95 includes a storage portion 95E which also serves as a support member, a pair of support members 95B mounted on a horizontal member (not shown) mounted on the upper end of the storage portion 95E across the storage portion 95E. It has a horizontally extending guide arm 95A attached to the upper end of these support members 95B. A lifting device 95C is attached to the guide arm 95A movably along the guide arm 95A. A wire 95D is attached to the lifting device 95C and a lifting device (not shown) is attached to the wire 95D.

  In the disassembling device 94, a grip 94F at the tip of the arm 94E mounted on a movable carriage moving along the connecting member 94A is used to grip the cut portion of the steam dryer 12 and the arm 94C mounted on the movable carriage The cutting portion is cut using a cutting machine 94D at the tip of the. The cut piece of the steam dryer 12 gripped by the gripping tool 94F is suspended by the lifting device 95 moving along the guide arm 95A of the storage container transfer device 95 by the operation of the arm 94E, and the inside of the lower cylindrical member 81C. In the storage container 96 located in The cut pieces of the steam dryer 12 sequentially generated by the cutting by the cutting machine 94D are gripped by the gripper 94F and sequentially stored in the storage container 96 suspended by the lifting device 95.

  When the storage container 96 is full of the cut pieces, the suspending device 95 moves just above the storage portion 95E to suspend the storage container 96 suspended therein into the storage portion 95E, and the storage portion 95E. Store inside. When a predetermined number of storage containers 96 in which the cut pieces of the steam dryer 12 are stored are stored in the storage section 95E, the open / close door 89A is opened, and the storage container transport device 95 shields radiation from the carry-in / out air lock 89. It is moved to the space 37 in the container 32. Using the lifting device 95C, all the storage containers 96 in the storage unit 95E are sequentially transferred into a plurality of transfer containers (not shown) placed on the bottom of the radiation shielding container 32. When the storage container 96 in the storage portion 95E is exhausted, the storage container transfer device 95 is moved again into the carry-in / out air lock 89. The steam dryer 12 is cut in the lower cylindrical member 81C, and the cut piece is stored in the storage container 96 suspended by the lifting device 95C, and the storage container 96 is stored in the storage portion 95E. . Then, the storage container 96 in which the cut pieces are stored is stored in the transport container in the radiation shielding container 32. Such a series of operations are performed until cutting of the steam dryer 12 is completed. The transport container cleaned by the water sprayer in the radiation shielding container 32 is transported to the outside through the opening 36A.

  After the cutting and unloading of the steam dryer 12 is completed, the cutting and unloading of the steam / water separator 11 in the reactor pressure vessel 3 by the disassembling device 94 and the storage container transporting device 95 is performed in the same manner as the steam dryer 12.

  The reactor internals and fuel debris in the reactor pressure vessel are cut (step S15). As shown in FIG. 39, the reactor internals such as the core shroud 6, the core support plate 9, the upper grid plate 10 and the control rod guide tube 13 which are the reactor internals present in the reactor pressure vessel 3 are cut. It is cut by the device 99.

  A support member 131 is attached to the inner surface of the intermediate cylindrical member 81B below the water-filled shielding bag 85, and a pair of winding devices 97A and 97B are installed on the upper surface of the support member 96. A wire 98A wound by the winding device 97A and a wire 98B wound by the winding device 97B are attached to the upper end of the main body 99A of the cutting device 99, respectively. The cutting device 99 disposed in the reactor pressure vessel 3 is supported by the wires 98A and 98B. Loading and unloading of the cutting device 99 and the support member 131 into and out of the reactor pressure vessel 3 are performed through a loading and unloading air lock 89.

  The configuration of the cutting device 99 will be described with reference to FIGS. 40 and 41. The cutting device 99 has a main body 99A, a rotating body 99B having a plurality of cutting blades 99C attached to the lower surface, and a balancing head 99D. A rotating body 99B connected to a motor (not shown) installed in the main body 99A is rotatably attached to the main body 99A. In the rotating body 99B, a groove 99E opened downward is formed to pass through the rotation center of the rotating body 99B. The suspension head 99D is attached to a moving table 99I disposed in the groove 99E and radially movably attached to the rotating body 99B. Although not shown, the moving table is provided with a rotating mechanism for rotating the drop head 99D and a moving mechanism for moving the drop head 99D in the direction of the rotation axis of the rotating body 99B. On the lower surface of the suspension head 99D, a jet nozzle 99F and a laser head 99G for water jet or abrasive water jet are attached.

  The rotating body 99B of the cutting device 99 is rotated in the reactor pressure vessel 3 to cut each of the in-core structures described above by the plurality of cutting edges 99C. The cutting of the furnace internals is performed while driving the winding devices 97A and 97B to unwind the wires 98A and 98B, respectively, and lowering the cutting device 99. When cutting the internals of the furnace with the cutting blade 99C, the suspension head 99D is present in the groove 99E so as to be located above the lower surface of the rotating body 99B.

  When cutting of the reactor internals is advanced by the cutting device 99 in the reactor pressure vessel 3, the cutting device 99 approaches the lower mirror portion 5. Soon, the fuel debris 39A present in the vicinity of the lower mirror portion 5 in the reactor pressure vessel 3 starts to be cut by the cutting device 99. On the surface of the fuel debris 39A, a mixture of a substance similar to ceramic and a metal melt is present, and it is difficult to cut with the cutting blade 99C of the cutting device 99 because the height of the mixture is high. For this reason, instead of the cutting blade 99C, the fuel debris 39A is led from the surface using any of the injection nozzle 99F and the laser head 99G provided in the suspension head 99D. In the case of using the injection nozzle 99F for water jet or abrasive water jet, the water jet or abrasive water jet is injected from the injection nozzle 99F toward the fuel debris 39A, and the fuel debris 39A is picked up by the water jet or abrasive water jet. . When the laser head 99G is used, the laser head 99G applies a laser to the surface of the fuel debris 39A to scrape the surface of the fuel debris 39A.

  In order for the fuel debris 39A to be efficiently shaken by the injection nozzle 99F or the laser head 99G, the sag head 99D is oriented in the rotational axis direction of the rotating body 99B so that the water jet or abrasive water jet or laser does not hit the cutting blade 99C. It is moved to the cutting blade 99C side so that the injection nozzle 99F or the laser head 99G comes out more forward than the cutting blade 99C. In such a state, injection of the water jet or the aggressive water jet to the fuel debris 39A or irradiation of the laser to the fuel debris 39A is performed. The injection of a water jet or an aggressive water jet or the irradiation of a laser is performed while rotating the folding head 99D.

By slowly rotating the rotating body 99B while moving the suspension head 99D in the longitudinal direction of the groove 99E, the fuel debris 39A of the fuel nozzle 39F or the laser head 99G can be obtained at any position in the radial and circumferential directions of the reactor pressure vessel 3. The reactor internals and the cut pieces of the fuel debris 39A generated by cutting by the cutting device 99 are carried out of the reactor pressure vessel 3 (step S16). The cutting piece is, for example, provided with a cavity at the center of the cutting device 99, and the suction device provided in the radiation shielding container 32 sucks the cutting piece from the cavity and stores it in the storage container. The storage container is transferred to a predetermined area in the radioactive waste disposal building and stored.
In addition, after cutting of the reactor internals in the reactor pressure vessel 3 by the cutting device 99 is started, cutting and unloading are substantially performed in parallel.

  The processing time can be shortened by cutting and unloading the reactor internals and the fuel debris 39 described above.

  DESCRIPTION OF SYMBOLS 2 ... Reactor, 3 ... Reactor pressure vessel, 4 ... Pressure vessel head, 5 ... Lower mirror part, 6 ... Core shroud, 7 ... Core, 9 ... Core support plate, 10 ... Upper lattice plate, 11 ... Air-water separation , 12: Steam dryer, 17: Reactor containment vessel, 18: Containment head, 23: Reactor building, 24: Operating floor, 25: Reactor well, 26: Dryer separator pool, 28: Shield plug, 29A , 29B: throttle plug, 30: heat insulating material, 32: radiation shielding container, 40: isolation chamber, 41: piercing device, 46: decontamination device, 47: shielding body conveying device, 48: shielding bag, 49: isolation house, 54: Isolation film, 70: Cutting and collecting device, 75: Loading and unloading chamber, 81: Isolation container, 81A: Upper cylindrical member, 81B: Intermediate cylindrical member, 81C: Lower cylindrical member, 89, 90: Loading and unloading air Click, 94 ... disassembling apparatus, 95 ... container carrying apparatus, 99 ... cutting apparatus, 100 ... biological shield, 210 ... head study jig, 300 ... entire cover device.

Claims (25)

A reactor well connected to the equipment temporary storage pool and the equipment temporary storage pool is formed in the operation floor of the reactor building, the reactor well is covered with a shield plug, and the equipment temporary storage pool and the reactor Reactor pressure placed in the reactor containment vessel at a nuclear power plant where a reactor core meltdown accident occurred in which the passage connecting the wells is closed with a throttle plug and the reactor containment vessel is placed in the reactor building interior A method of opening the container,
An operation to open the reactor pressure vessel in parallel with the spent fuel unloading operation from the fuel storage pool by maintaining an isolation area where radiation and radioactive material do not leak to the operating floor in the equipment temporary storage pool A method of opening a reactor pressure vessel characterized by securing a space. A reactor well connected to the equipment temporary storage pool and the equipment temporary storage pool is formed in the operation floor of the reactor building, the reactor well is covered with a shield plug, and the equipment temporary storage pool and the reactor A method of opening a reactor pressure vessel disposed in the reactor containment vessel in a nuclear power plant where a passage connecting the wells is closed with a throttle plug and the reactor containment vessel is disposed in the reactor building interior There,
Securing a working space where the operation of opening the reactor pressure vessel can be performed in parallel with the operation of taking out spent fuel from the fuel storage pool;
The work space is closed with a lid having a shield and an airtight seal on the upper surface of the equipment temporary storage pool to maintain radiation and radioactive materials in an isolated area where leakage to the operating floor occurs, the reactor well and the equipment temporary storage pool The first through hole is formed in the throttle plug that seals the fuel tank, and the device in the reactor well is disassembled through the first through hole, and carried out through the prepared temporary storage pool. how to open the features and to RuHara child reactor pressure vessel. As maintenance of the isolation area in the equipment temporary storage pool, the equipment having the function of making the shield open and close on the upper surface and the function of making airtight at the closing time and the shield open and close on the throttle plug side and air tight is disposed in the apparatus temporary storage pool. A method of opening a reactor pressure vessel according to claim 1 or claim 2. The reactor well is decontaminated from the equipment temporary storage pool through the first through hole and sealed in the reactor well and then the first radiation shield is transferred to the reactor containment vessel below the shield plug. The reactor pressure as set forth in claim 2 , wherein the first radiation shield covers the containment head of the reactor vessel to reduce contamination and radiation in the reactor well prior to dismantling equipment in the reactor well. How to open the container. The first radiation shield is transferred from the equipment temporary storage pool through the first through hole into the reactor well sealed with the shield plug, and the containment head of the reactor containment vessel below the shield plug. In place of the shield plug covered with the first radiation shield and covered with the first radiation shield, the second radiation shield serving as a platform for disassembling the equipment in the reactor well is replaced with The method for opening the reactor pressure vessel according to claim 2, wherein the equipment in the reactor well is disassembled.   The platform which is also used as the second radiation shield body is characterized in that the disassembling operation arm is attached to the lower surface so that the disassembling operation arm can be moved in the circumferential direction, the radial direction and the vertical direction in the reactor well. The method of opening the reactor pressure vessel described in 4. A reactor well connected to the equipment temporary storage pool and the equipment temporary storage pool is formed in the operation floor of the reactor building, the reactor well is covered with a shield plug, and the equipment temporary storage pool and the reactor A method of opening a reactor pressure vessel disposed in the reactor containment vessel in a nuclear power plant where a passage connecting the wells is closed with a throttle plug and the reactor containment vessel is disposed in the reactor building interior There,
Close the top of the equipment temporary storage pool with a cover that has shielding and airtightness, and maintain it in an isolated area where radiation and radioactive materials do not leak to the operating floor,
Forming a first through hole in the throttle plug from the device temporary storage pool;
After providing a first radiation shield on top of the equipment in the reactor well, replacing the shield plug and the second radiation shield shared platform,
The equipment temporary placement pool is shredded and an airtight shredded area is formed in which a storage container for storing small pieces is disposed.
Reactor pressure characterized by shredding and storing the equipment in the reactor well in the shredding area in the equipment temporary storage pool through the first through hole, and carrying it out of the equipment temporary storage pool How to open the container. 8. The atom according to claim 7, wherein the shredding area disposed in the equipment temporary storage pool shreds and encloses equipment for storing the small fragments in the storage container in a work container having air tightness. How to open the furnace pressure vessel. As a storage container unloading method in the shredding area arranged in the equipment temporary storage pool,
A container capable of storing water, a partition inside the container and a passage through which the storage container can pass through the lower surface of the partition, with the water being stored to the upper side from the passage on the lower surface of the partition The method for opening a reactor pressure vessel according to claim 7 or 8, wherein the reactor pressure vessel is unloaded via a water storage container having a loading port on one side and a discharge port on the opposite side. After providing the first radiation shield at the top of the device before Symbol reactor well, remove the shield plug and the throttle plug,
Install a separate house on the operation floor of the equipment temporary storage pool and reactor well,
Install a partition in the passage of the part from which the throttle plug has been removed to connect equipment temporary storage pool and reactor well,
Install partitions in the isolated house on the operation floor of the equipment temporary storage pool and reactor well,
Install partitions on the operation floor of equipment temporary storage pool and reactor well,
And equipment temporary pool and the reactor well, claim 2 or claim 7, characterized in that partitioning the chamber with an isolation house on the device temporary pool, each airtight independently isolated house on the reactor well The method of opening the reactor pressure vessel described in 4.   The partition for partitioning the equipment temporary storage pool, the reactor well, the isolated house on the device temporary storage pool, and the isolated house on the reactor well into independently air-tight rooms has a radiation shielding function. The method for opening a reactor pressure vessel according to claim 10, characterized in that:   11. The method for opening a reactor pressure vessel according to claim 4, wherein a shielding bag filled with water is used as the first radiation shielding body.   After dismantling all the equipment in the reactor well covering the pressure vessel head attached to the reactor pressure vessel and taking it out through the equipment temporary placement pool, the pressure vessel head has a second through hole. The camera is inserted from the second through hole, the inside of the pressure vessel head is inspected, and then the equipment in the reactor pressure vessel is carried out to the outside of the reactor building. Item 8. A method for opening a reactor pressure vessel according to Item 7.   The method for opening the reactor pressure vessel according to claim 13, wherein the means for forming the second through hole and the camera are carried in through the equipment temporary storage pool. A shielding vessel containing means for forming a second through hole and a camera is installed on the upper surface of the platform which also serves as the second radiation shield through an isolation house installed on the reactor well;
The second radiation shielding body is also provided in advance with a removable plug in the passage hole for passing the means for forming the second through hole in advance in the platform which also serves as the second through hole, and the means for forming the second through hole is A second through hole is made in the pressure vessel head attached to the reactor pressure vessel by removing the closure plug, and the camera is inserted from the second through hole, and the inside of the pressure vessel head is inspected. The method for opening the reactor pressure vessel according to claim 7, wherein the equipment in the reactor pressure vessel is then carried out outside the reactor building.   The method for opening a reactor pressure vessel according to claim 13 or 15, wherein the method is applied to the subsequent unloading operation of equipment in the reactor pressure vessel based on the result of the investigation. A reactor well connected to the equipment temporary storage pool and the equipment temporary storage pool is formed in the operation floor of the reactor building, the reactor well is covered with a shield plug, and the equipment temporary storage pool and the reactor A method of opening a reactor pressure vessel disposed in the reactor containment vessel in a nuclear power plant where a passage connecting the wells is closed with a throttle plug and the reactor containment vessel is disposed in the reactor building interior There,
Install a separate house on the operation floor of the equipment temporary storage pool and reactor well,
After removing the equipment in the reactor well,
An isolation vessel covering a pressure vessel head attached to the reactor pressure vessel is disposed in the reactor well and the isolation house;
A method of opening a reactor pressure vessel, characterized by removing the pressure vessel head removed from the reactor pressure vessel and the equipment in the reactor pressure vessel within the isolation vessel. Means for installing an isolation vessel covering a pressure vessel head attached to the reactor pressure vessel in the reactor well and the isolation house,
A removable plug is provided in advance in the passage for the isolation container to pass through the second radiation shield and platform.
When installing the isolation container, the isolation container is set using the passage hole from which the stopper is removed, and radiation shielding of the reactor well surface is carried out by the second radiation shield combined platform. Item 18. A method for opening a reactor pressure vessel according to Item 17. A reactor well connected to the equipment temporary storage pool and the equipment temporary storage pool is formed in the operation floor of the reactor building, the reactor well is covered with a shield plug, and the equipment temporary storage pool and the reactor A method of opening a reactor pressure vessel disposed in the reactor containment vessel in a nuclear power plant where a passage connecting the wells is closed with a throttle plug and the reactor containment vessel is disposed in the reactor building interior There,
Securing a working space where the operation of opening the reactor pressure vessel can be performed in parallel with the operation of taking out spent fuel from the fuel storage pool;
An entire cover device has been used from the fuel storage pool having a first sheet surrounding the side of the reactor building and a second sheet disposed above the operating floor of the reactor building and covering the top surface having the first opening. A space necessary for work performed in parallel with the fuel unloading work is formed, and a gripper of a crane is moved below the entire cover device through the first opening, on the operating floor of the reactor building. the falling objects gripped by the jaws is moved upward of the entire cover device through said first opening, Tozashi sealing the first opening, the reactor pressure vessel after the dismantling of the falling objects how to open the features and to RuHara child reactor pressure vessel that the work of opening is performed.   20. The method of opening a reactor pressure vessel according to claim 19, wherein the overall covering device can also be used for removing dropped objects scattered to the operating floor in the reactor building. The second sheet is a sheet having elasticity, and a storage container obtained by disassembling and storing the device in the reactor well or the device in the reactor pressure vessel is carried out from the first opening. 20. A method of opening a reactor pressure vessel according to claim 19.   An apparatus containing container having another crane equipped with a gripping tool and an opening / closing sheet for opening / closing the collection surface on the collection surface of the fallen object is placed in the first opening or the space, and the opening / closing sheet is opened or closed. While holding the unloading container in which the equipment in the reactor well or the equipment in the reactor pressure vessel is disassembled and stored with the other crane's grips, and a storage container in which the dismantled pieces are stored in the device-containing container The method for opening a reactor pressure vessel according to claim 19, wherein the reactor pressure vessel is unloaded.   The reactor according to any one of claims 2 to 22, wherein the equipment in the reactor well is a containment head and a heat retaining material, or a containment head and a heat retaining material, and a pressure vessel head. How to open the pressure vessel.   The method for opening a reactor pressure vessel according to any one of claims 15 to 22, wherein the equipment in the reactor pressure vessel is a steam separator or a steam dryer. After working to open the reactor pressure vessel according to claim 1 or a method of opening the reactor pressure vessel according to any one of 24, to dismantle the fuel debris of the reactor pressure vessel bottom, reactor building outside A method of taking out fuel debris, which is carried out.

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