Core meltdown material processing device and nuclear facility

Abstract

To suppress the occurrence of phreatic explosions by avoiding contact between a core meltdown material and cooling water in a core meltdown material processing device and a nuclear facility.SOLUTION: A core meltdown material processing device in which a reactor is supported by a structure installed on a foundation part of a reactor containment vessel and which processes a core meltdown material falling from the lower part of a reactor vessel, includes: a cavity which is provided in the foundation part with a hollow shape; a transfer passage which has one end opened to the upper surface of the foundation part and the other end connected to the cavity; and a partition wall which has a cylindrical shape, has one end in the axial direction tightly connected to the lower part of the reactor vessel and the other end in the axial direction tightly connected to the foundation part so as to surround the other end of the transfer passage opened on the upper surface of the foundation part.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a reactor core melt treatment device and a nuclear power facility.

Background Art

[0002] A reactor containment vessel is erected on a solid ground such as rock, and a reactor is disposed inside. The reactor is supported by a concrete structure provided at the base of the reactor containment vessel. In a nuclear power facility, as a severe accident, an accident in which the reactor core melt flows out of the reactor vessel is assumed. Since the reactor core melt melts the lower part of the reactor vessel and drops downward, a cavity is provided below the reactor vessel, and the reactor core melt is received by the cavity and cooled by cooling water. As such a nuclear power facility, for example, there is one described in Patent Document 1.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Since the reactor core melt is at several thousand degrees Celsius, if the cooling water directly contacts inside the cavity, there is a risk of a steam explosion occurring. Therefore, it is desirable to avoid contact between the reactor core melt that has fallen from the lower part of the reactor vessel and the cooling water and cool it over time.

[0005] The present disclosure solves the above-described problems, and an object thereof is to provide a reactor core melt treatment device and a nuclear power facility that suppress the occurrence of a steam explosion by avoiding contact between the reactor core melt and the cooling water.

Means for Solving the Problems

[0006] The core melt treatment device of the present disclosure for achieving the above object is a core melt treatment device that supports a nuclear reactor by a structure installed at the base of a reactor containment vessel and treats the core melt that falls from the lower part of the reactor vessel. In this device, a cavity formed in a hollow shape is provided in the base part, a transfer passage having one end opening on the upper surface of the base part and the other end communicating with the cavity, and a partition part that has a cylindrical shape and is connected to the base part without a gap so as to surround the other end of the transfer passage where one axial end is connected to the lower part of the reactor vessel without a gap and the other axial end opens on the upper surface of the base part.

[0007] Further, the nuclear power facility of the present disclosure includes a reactor containment vessel, a nuclear reactor disposed inside the reactor containment vessel, and the core melt treatment device.

Advantages of the Invention

[0008] According to the core melt treatment device and the nuclear power facility of the present disclosure, it is possible to suppress the occurrence of a steam explosion by avoiding contact between the core melt and the cooling water.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0010] Hereinafter, with reference to the drawings, preferred embodiments of the present disclosure will be described in detail. Note that the present disclosure is not limited by this embodiment, and when there are multiple embodiments, those configured by combining each embodiment are also included. In addition, the components in the embodiments include those that can be easily assumed by those skilled in the art, substantially the same ones, and those within the so-called equivalent range.

[0011] <Nuclear power facility> FIG. 1 is a schematic diagram showing the nuclear power facility of this embodiment.

[0012] As shown in FIG. 1, the nuclear power facility 10 is applied to a nuclear power plant. The nuclear power facility 10 of this embodiment uses light water as a reactor coolant and a neutron moderator, forms high-temperature and high-pressure water that does not boil throughout the primary system, sends the high-temperature and high-pressure water to a steam generator to generate steam by heat exchange, and sends the steam to a turbine generator to generate electricity, and is equipped with a pressurized water reactor (PWR: Pressurized Water Reactor). However, the reactor is not limited to a pressurized water reactor, and can also be applied to other reactors such as a boiling water reactor (BWR: Boiling Water Reactor).

[0013] The reactor containment vessel 11 is arranged on a solid ground G such as rock. The reactor containment vessel 11 includes a base portion 12 and a containment vessel main body 13. The base portion 12 is installed on the ground G, and the containment vessel main body 13 is erected on the base portion 12. The base portion 12 and the containment vessel main body 13 form an integral structure. The containment vessel main body 13 is provided with a structure 14 constructed by reinforced concrete or the like inside. The structure 14 is arranged inside the containment vessel main body 13 above the base portion 12.

[0014] The reactor containment vessel 11 has a reactor 15 disposed at its central part. The structure 14 defines a cylindrical space 16 at the central part of the reactor containment vessel 11. The reactor 15 is disposed in the space 16 and is suspended and supported by the structure 14 forming the inner wall of the space 16. A plurality of steam generators 17 are disposed around the reactor 15 in the reactor containment vessel 11. The plurality of steam generators 17 are supported by the structure 14. The reactor 15 and the plurality of steam generators 17 are connected by a cooling water pipe 18.

[0015] A cavity 19 is defined and formed below the reactor 15 in the reactor containment vessel 11. The cavity 19 receives and cools the core melt that falls from the reactor 15. The reactor containment vessel 11 is provided with a cooling water pit 20 for storing cooling water at the base 12, and a cooling water injection device 21 is provided at the upper part of the containment vessel body 13. The cooling water pit 20 is connected to the cooling water injection device 21 by a cooling water path 22, and a cooling water pump 23 is provided in the cooling water path 22.

[0016] The reactor 15 is configured with a core 25 disposed inside a reactor vessel 24. The reactor vessel 24 is configured with a reactor vessel lid detachably provided at the upper part of the reactor vessel body. The reactor vessel 24 is provided with an inlet nozzle for supplying light water (coolant) as primary cooling water and an outlet nozzle for discharging the light water at its upper side. The reactor vessel 24 has the cooling water pipes 18 from the steam generators 17 connected to the inlet nozzle and the outlet nozzle respectively. The core 25 disposed inside the reactor vessel 24 is composed of a plurality of fuel assemblies. Each fuel assembly is configured by bundling a large number of fuel rods in a lattice shape by a support lattice. Note that the core 25 has a plurality of control rods for controlling the output of the reactor 15 arranged together with the large number of fuel rods.

[0017] The nuclear reactor 15 releases neutrons by the nuclear fission of the nuclear fuel that constitutes the reactor core 25. Light water as a moderator and primary coolant reduces the kinetic energy of the released fast neutrons to thermal neutrons, making it easier for new nuclear fissions to occur, and at the same time, takes away the generated heat for cooling. At this time, by inserting control rods into the reactor core 25 and adjusting the number of neutrons generated in the reactor core 25, the output of the nuclear reactor 15 is adjusted.

[0018] The steam generator 17 is connected via a steam pipe to a steam turbine provided outside the nuclear reactor containment vessel 11. The steam turbine is connected to a generator. The steam generator 17 generates steam by performing heat exchange between the high-temperature primary coolant supplied from the nuclear reactor 15 and the secondary coolant. The generated steam is sent to the steam turbine to drive it, and power generation is performed by the generator. The steam that has driven the steam turbine is returned to the steam generator 17 after being cooled.

[0019] <Apparatus for treating reactor core melt> FIG. 2 is a schematic diagram showing the apparatus for treating the reactor core melt of the present embodiment.

[0020] As shown in FIG. 2, the nuclear power facility 10 includes an apparatus 30 for treating the reactor core melt. The apparatus 30 for treating the reactor core melt is for treating the reactor core melt that falls from the lower part of the reactor vessel 24 that constitutes the nuclear reactor 15, with the nuclear reactor 15 supported by a structure 14 installed at the base 12 of the nuclear reactor containment vessel 11. The apparatus 30 for treating the reactor core melt includes a cavity 19, a transfer passage 31, and a partition portion 32.

[0021] The nuclear reactor 15 is disposed in a space portion 16 formed in the structure 14. The nuclear reactor 15 has a cylindrical shape with its upper and lower portions closed, and the space portion 16 has a cylindrical shape with its upper and lower portions open. Since the outer diameter of the nuclear reactor 15 is smaller than the inner diameter of the space portion 16, a gap is secured between the outer wall surface of the nuclear reactor 15 and the inner wall surface of the space portion 16. Inside the reactor vessel 24, a reactor core 25 is disposed. The reactor vessel 24 is provided with a plurality of inlet nozzles (inlet plena) 24a at its upper side portion and a plurality of outlet nozzles (outlet plena) 24b. Coolant pipes 18a, 18b from the steam generators 17 (see FIG. 1) are connected to the respective inlet nozzles 24a and the respective outlet nozzles 24b.

[0022] The nuclear reactor 15 (reactor vessel 24) is disposed in the space portion 16 of the structure 14, and a gap is secured between it and the inner wall surface of the structure 14. The nuclear reactor 15 (reactor vessel 24) is suspended and supported by the structure 14 by placing the plurality of inlet nozzles 24a and the plurality of outlet nozzles 24b on a stepped portion 14a of the structure 14.

[0023] The base portion 12 is constructed of reinforced concrete or the like, and a refractory material (for example, a metal plate) 12a is disposed on its upper surface portion. The cavity 19 is provided in the base portion 12 located below the nuclear reactor 15 in a hollow shape, and is disposed at a position horizontally displaced from the central portion of the nuclear reactor 15. The cavity 19 is a partitioned room and functions as a diffusion space portion where the reactor core melt diffuses. The cavity 19 is provided with cooling portions 41, 42 on its lower surface portion and each side surface portion. Further, a sacrificial material concrete 43 is provided above the cooling portion 41 on the lower surface portion of the cavity 19. The cooling portions 41, 42 are, for example, cooling tanks for circulating cooling water. The sacrificial material concrete 43 is a sacrificial material that lowers the melting point of the reactor core melt and makes it less viscous, and is not limited to concrete.

[0024] The transfer passage 31 has one end opening on the upper surface of the base portion 12 and the other end communicating with the cavity 19. The transfer passage 31 has an L shape and includes a vertical passage 51 and a horizontal passage 52. The upper end of the vertical passage 51 opens on the upper surface of the base portion 12, and the lower end communicates with one end of the horizontal passage 52. The other end of the horizontal passage 52 communicates with the cavity 19. In this case, it is preferable that the horizontal passage 52 slopes downward from the vertical passage 51 toward the cavity 19. The transfer passage 31 is a through-hole provided through the base portion 12, and a refractory material (for example, a metal pipe, etc.) 53 is disposed on the inner wall surface of the through-hole. Note that the transfer passage 31 is not limited to this configuration. Note that the transfer passage 31 may slope or be curved, for example, from the upper surface of the base portion 12 toward the cavity 19.

[0025] The partition portion 32 has a cylindrical shape. The partition portion 32 is provided with its axial direction along the vertical direction and is disposed between the reactor vessel 24 and the base portion 12. One end (upper end) in the axial direction (vertical direction) of the partition portion 32 is connected to the lower part of the reactor vessel 24 without a gap, and the other end (lower end) in the axial direction (vertical direction) is connected to the base portion 12 without a gap so as to surround the other end (upper end) of the transfer passage 31 that opens on the upper surface of the base portion 12 (refractory material 12a).

[0026] A support plate 61 having a ring shape is fixed to the upper surface portion of the base portion 12. The outer diameter of the support plate 61 is larger than the outer diameter of the space portion 16, and the inner diameter is smaller than the outer diameter of the reactor vessel 24. Note that the support plate 61 is not limited to such dimensions, and the support plate 61 may be disposed on the upper surface of the refractory material 12a of the base portion 12. It is preferable that the outer diameter of the partition portion 32 is approximately the same as the outer diameter of the reactor vessel 24, but it may be smaller or larger than the outer diameter of the reactor vessel 24. The upper end of the partition portion 32 is connected to the lower part of the reactor vessel 24 without a gap, and the lower end is fixed to the upper surface of the support plate 61 without a gap. In this case, the inner diameter of the upper end of the transfer passage 31 is smaller than the inner diameter of the partition portion 32. However, the support plate 61 may be omitted, and the lower end of the partition portion 32 may be fixed to the upper surface of the base portion 12 (refractory material 12a) without a gap.

[0027] In this case, the partition wall portion 32 supports a part of the load of the reactor vessel 24 (reactor 15) with respect to the base portion 12. However, the partition wall portion 32 may not support the load of the reactor vessel 24 (reactor 15) with respect to the base portion 12. That is, the partition wall portion 32 may be connected without a gap so that the lower end portion is movable in the axial direction (vertical direction) with respect to the support plate 61 (or the base portion 12). In this case, the thermal elongation in the reactor vessel 24 can be absorbed. Further, although the reactor vessel 24 (reactor 15) is suspended and supported by the structure 14 by the inlet nozzle 24a and the outlet nozzle 24b, the suspension support may be abolished and supported at the lower part only by the partition wall portion 32 or by the partition wall portion 32 and another support member or the like.

[0028] The core melt treatment device 30 has a sacrificial material concrete 62. The sacrificial material concrete 62 is disposed on the upper surface of the base portion 12 facing the lower portion of the reactor vessel 24. Therefore, the other end of the transfer passage 31 opening on the upper surface of the base portion 12 is blocked by the sacrificial material concrete 62. The sacrificial material concrete 62 is a sacrificial material that lowers the melting point of the core melt and makes it less viscous, and is not limited to concrete.

[0029] The base portion 12 is an inclined support surface 12b in which the upper surface inside the partition wall portion 32 (support plate 61) inclines downward toward the central portion, and the sacrificial material concrete 62 is disposed on the upper surface of the inclined support surface 12b. It is preferable that a refractory material (for example, a metal plate or the like) is disposed on the upper surface of the inclined support surface 12b. Since the sacrificial material concrete 62 is disposed on the upper surface of the inclined support surface 12b, the lower surface has the same shape as the inclined support surface 12b and is disposed without a gap. And the sacrificial material concrete 62 is an inclined receiving surface 62a whose upper surface inclines downward toward the central portion. In this case, it is preferable that the sacrificial material concrete 62 gradually increases the vertical thickness from the outer peripheral portion toward the central portion. Note that the upper surface of the sacrificial material concrete 62 is the inclined receiving surface 62a, but it may be a horizontal surface.

[0030] The partition section 32 is provided with an opening / closing door 63 for maintenance. The opening / closing door 63 for maintenance is for an operator to open the opening / closing door 63 for maintenance and enter the inside of the partition section 32 to inspect the reactor vessel 24 and the like during regular inspections of the nuclear reactor 15 and the like.

[0031] As described above, the structure 14 defines a cylindrical space section 16, and the reactor vessel 24 (nuclear reactor 15) is disposed and supported in the space section 16. A gap is secured between the outer wall surface of the reactor vessel 24 and the inner wall surface of the space section 16. The gap between the outer wall surface of the reactor vessel 24 and the inner wall surface of the space section 16 is provided around the entire circumference of the reactor vessel 24 and is open at the upper and lower portions along the vertical direction. The gap functions as a cooling air passage 64 through which cooling air flows. That is, a blower 65 is disposed in the structure 14, and by driving the blower 65, cooling air flowing upward from the lower portion to the upper portion is supplied to the cooling air passage 64, thereby cooling the inner wall surface of the structure 14 that partitions the space section 16.

[0032] Also, the gap between the outer wall surface of the reactor vessel 24 and the inner wall surface of the space section 16 functions as a cooling water passage 66 through which cooling water flows. The nuclear power facility 10 cools the nuclear reactor 15, for example, by injecting cooling water from a cooling water injection device 21 (see FIG. 1) when a severe accident occurs. The cooling water that has cooled the nuclear reactor 15 descends through the cooling water passage 66 and is discharged to the outside. At this time, a partition section 32 is disposed between the lower portion of the reactor vessel 24 and the base section 12, and the cooling water does not enter the inside of the partition section 32.

[0033] <Method for treating core melt> FIGS. 3 and 4 are schematic diagrams showing the operation of the core melt treatment device.

[0034] As shown in FIG. 2, in the nuclear facility 10, for example, it is assumed that a severe accident occurs and a core damage accident due to core melting occurs. At this time, as shown in FIG. 3, in the nuclear reactor 15, the lower part of the reactor vessel 24 is damaged, and the core melt 25A in which the core 25 has melted flows out. The core melt 25A flowing out from the lower part of the reactor vessel 24 falls toward the sacrificial material concrete 62 provided below the reactor vessel 24 inside the partition part 32. The sacrificial material concrete 62 receives the core melt 25A that has fallen from the lower part of the reactor vessel 24 at the central part. The core melt 25A includes the melted core 25 and the in-vessel structures melted along with the melted core 25.

[0035] The sacrificial material concrete 62 is melted and mixed with the core melt 25A, thereby lowering the melting point of the core melt 25A and making it less viscous. That is, the core melt 25A that has fallen onto the sacrificial material concrete 62 melts the sacrificial material concrete 62 by its own heat, mixes with the melted sacrificial material concrete 62, and its melting point decreases and it becomes less viscous. Then, as shown in FIG. 4, the core melt 25B mixed with the sacrificial material concrete 62 falls from the melted part of the sacrificial material concrete 62 into the vertical passage 51 of the transfer passage 31. After that, the core melt 25B flows from the vertical passage 51 of the transfer passage 31 through the horizontal passage 52 and spreads in the cavity 19. At this time, the core melt 25B comes into contact with the sacrificial material concrete 43, and by melting and mixing, its melting point further decreases and it becomes less viscous. Also, the core melt 25B is cooled by the cooling parts 41, 42. Then, the core melt 25B becomes the low-temperature core melt 25C.

[0036] On the one hand, when a severe accident occurs, the cooling water injection device 21 (see FIG. 1) operates to inject cooling water to cool the reactor 15. The cooling water that has cooled the reactor 15 descends through the cooling water passage 66 and is discharged to the outside. At this time, the cooling water descends along the outer wall surface of the reactor vessel 24 and the outer wall surface of the partition portion 32, flows on the base portion 12, and is discharged to the outside. Therefore, the cooling water does not enter the inside of the reactor vessel 24 or the inside of the partition portion 32. That is, the partition portion 32 prevents the contact between the cooling water and the core melt 25A, and suppresses the occurrence of a steam explosion.

[0037] [Operation and Effect of this Embodiment] In the core melt treatment device according to the first aspect, the reactor 15 is supported by a structure 14 installed on the base portion 12 of the reactor containment vessel 11, and in the core melt treatment device 30 that treats the core melt 25A that falls from the lower part of the reactor vessel 24, a cavity 19 provided in a hollow shape in the base portion 12, a transfer passage 31 having one end opening to the upper surface of the base portion 12 and the other end communicating with the cavity 19, and a partition portion 32 that is cylindrical, has one end in the axial direction connected to the lower part of the reactor vessel 24 without a gap, and is connected to the base portion 12 without a gap so as to surround the other end of the transfer passage 31 whose other end in the axial direction opens to the upper surface of the base portion 12.

[0038] According to the core melt treatment device according to the first aspect, when the lower part of the reactor vessel 24 is damaged and the core melt 25A in which the core 25 has melted falls, the core melt 25A flows through the transfer passage 31 and is cooled in the cavity 19 while being partitioned from the outside inside the partition portion 32. Therefore, the core melt 25A is prevented from contacting the cooling water that has cooled the reactor 15. As a result, by avoiding the contact between the core melt 25A and the cooling water, the occurrence of a steam explosion can be suppressed.

[0039] Moreover, according to the core melt treatment apparatus, by simply providing the partition wall portion 32 that connects the lower part of the reactor vessel 24 and the base portion 12, contact between the core melt 25A and the cooling water can be avoided, and separately, the core melt 25A can be cooled early without the need for power. Furthermore, by simply providing the partition wall portion 32, complication of the structure can be suppressed and an increase in manufacturing cost can be suppressed.

[0040] The core melt treatment apparatus according to the second aspect is the core melt treatment apparatus according to the first aspect, and further, a sacrificial material concrete (sacrificial material) 62 that lowers the melting point of the core melt 25A and reduces its viscosity is disposed on the upper surface of the base portion 12 facing the lower part of the reactor vessel 24. Thereby, the core melt 25A that has fallen from the lower part of the reactor vessel 24 is received by the sacrificial material concrete 62 inside the partition wall portion 32 and melted and mixed, so that the melting point is lowered and the viscosity is reduced, and it can be cooled early.

[0041] The core melt treatment apparatus according to the third aspect is the core melt treatment apparatus according to the second aspect, and further, the upper surface of the base portion 12 facing the lower part of the reactor vessel 24 is an inclined support surface 12b that slopes downward toward the center, and the sacrificial material concrete 62 is disposed on the inclined support surface 12b. Thereby, the core melt 25B in which the sacrificial material concrete 62 is melted and mixed falls onto the transfer passage 31 along the inclined support surface 12b, suppressing the retention of the core melt 25B at the base portion 12, enabling the core melt 25B to be spread and cooled early, and suppressing damage to the base portion 12.

[0042] The reactor core melt treatment apparatus according to the fourth aspect is the reactor core melt treatment apparatus according to the second or third aspect, and further, the sacrificial material concrete 62 has a greater thickness in the vertical direction from the outer peripheral portion toward the central portion. Thereby, since the reactor core melt 25A that has fallen from the lower part of the reactor vessel 24 is received at the central portion of the sacrificial material concrete 62, by increasing the thickness of the central portion of the sacrificial material concrete 62, the melting and mixing amount of the sacrificial material concrete 62 with respect to the reactor core melt 25A can be increased, and the melting point can be lowered at an early stage to reduce the viscosity.

[0043] The reactor core melt treatment apparatus according to the fifth aspect is the reactor core melt treatment apparatus according to any one of the first to fourth aspects, and further, an opening / closing door 63 for maintenance is provided in the partition portion 32. Thereby, during the periodic inspection of the nuclear reactor 15, an operator can open the opening / closing door 63 for maintenance and enter the inside of the partition portion 32, and the inspection of the reactor vessel 24 and the like can be easily performed.

[0044] The reactor core melt treatment apparatus according to the sixth aspect is the reactor core melt treatment apparatus according to any one of the first to fifth aspects, and further, the partition portion 32 supports the load of the reactor vessel 24 with respect to the base portion 12. Thereby, the reactor vessel 24 can be firmly supported.

[0045] The reactor core melt treatment apparatus according to the seventh aspect is the reactor core melt treatment apparatus according to any one of the first to sixth aspects, and further, the outer diameter of the partition portion 32 is equal to or less than the outer diameter of the reactor vessel 24. Thereby, it is possible to suppress the cooling water that descends outside the reactor vessel 24 from coming into contact with the partition portion 32, suppress the intrusion of the cooling water into the inside of the partition portion 32, and prevent the contact between the reactor core melt 25A and the cooling water.

[0046] The reactor core melt processing apparatus according to the eighth aspect is the reactor core melt processing apparatus according to any one of the first to seventh aspects, and further, the structure 14 defines a cylindrical space portion 16, the reactor vessel 24 is disposed in the space portion 16, and a cooling air passage 64 through which cooling air flows is provided between the outer wall surfaces of the reactor vessel 24 and the partition portion 32 and the inner wall surface of the space portion 16. Thereby, during normal operation of the nuclear reactor 15, the structure 14 that supports the nuclear reactor 15 can be cooled by the cooling air flowing through the cooling air passage 64, and the durability of the structure 14 can be improved.

[0047] The reactor core melt processing apparatus according to the ninth aspect is the reactor core melt processing apparatus according to any one of the first to eighth aspects, and further, the structure 14 defines a cylindrical space portion 16, the reactor vessel 24 is disposed in the space portion 16, and a cooling water passage 66 through which cooling water flows is provided between the outer wall surfaces of the reactor vessel 24 and the partition portion 32 and the inner wall surface of the space portion 16. Thereby, the cooling water for cooling the nuclear reactor 15 can be discharged from the cooling water passage 66 to the outside, and the intrusion of the cooling water into the inside of the partition portion 32 can be suppressed.

[0048] The nuclear power facility according to the tenth aspect includes a reactor containment vessel 11, a nuclear reactor 15 disposed inside the reactor containment vessel 11, and a reactor core melt processing apparatus 30. Thereby, the reactor core melt processing apparatus 30 can suppress the occurrence of a steam explosion by avoiding contact between the reactor core melt 25A and the cooling water, and can improve safety.

Explanation of reference numerals

[0049] 10 Nuclear power facility 11 Reactor containment vessel 12 Foundation part 12a Refractory 12b Inclined support surface 13 Containment vessel main body 14 Structure 14a Step part 15 Nuclear reactor 16 Space portion 17 Steam generator 18, 18a, 18b Cooling water pipe 19 Cavity 20 Cooling water pit 21 Cooling water injection device 22 Cooling water path 23 Cooling water pump 24 Reactor vessel 24a Inlet nozzle 24b Outlet nozzle 25 Reactor core 25A, 25B, 25C Core melt 30 Core melt treatment device 31 Transfer passage 32 Partition part 41, 42 Cooling part 43 Sacrificial material concrete 51 Vertical passage 52 Horizontal passage 53 Refractory 61 Support plate 62 Sacrificial material concrete (sacrificial material) 63 Maintenance opening / closing door 64 Cooling air path 65 Blower 66 Cooling water path

Claims

1. In a reactor core melt treatment device that supports a reactor by a structure installed at the base of a reactor containment vessel and treats a reactor core melt that falls from the lower part of the reactor vessel, a cavity provided in a hollow shape in the base portion; a transfer passage having one end opening to the upper surface of the base portion and the other end communicating with the cavity; a partition portion that is cylindrical, has one axial end connected to the lower part of the reactor vessel without a gap, and is connected to the base portion without a gap so as to surround the other end of the transfer passage whose other axial end opens to the upper surface of the base portion; A reactor core melt treatment device comprising the above.

2. A sacrificial material that lowers the melting point of the reactor core melt and makes it less viscous is arranged on the upper surface of the base portion facing the lower part of the reactor vessel. The reactor core melt treatment device according to claim 1.

3. The upper surface of the base portion facing the lower part of the reactor vessel is an inclined support surface that slopes downward toward the center portion, and the sacrificial material is arranged on the inclined support surface. The reactor core melt treatment device according to claim 2.

4. The sacrificial material has a greater vertical thickness from the outer peripheral portion toward the center portion. The reactor core melt treatment device according to claim 2 or claim 3.

5. The partition portion is provided with an opening / closing door for maintenance. The reactor core melt treatment device according to claim 1.

6. The partition portion supports the load of the reactor vessel with respect to the base portion. The reactor core melt treatment device according to claim 1.

7. The outer diameter of the partition portion is less than or equal to the outer diameter of the reactor vessel. The reactor core melt treatment device according to claim 1.

8. The structure defines a cylindrical space portion, the reactor vessel is disposed in the space portion, and a cooling air passage through which cooling air flows is provided between the outer wall surfaces of the reactor vessel and the partition wall portion and the inner wall surface of the space portion. The reactor core melt treatment apparatus according to claim 1.

9. The structure defines a cylindrical space portion, the reactor vessel is disposed in the space portion, and a cooling water passage through which cooling water flows is provided between the outer wall surfaces of the reactor vessel and the partition wall portion and the inner wall surface of the space portion. The reactor core melt treatment apparatus according to claim 1.

10. A reactor containment vessel, A reactor disposed inside the reactor containment vessel, The reactor core melt treatment apparatus according to claim 1, and a nuclear power facility including the same.

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