JP6525746B2 - Heat resistant materials and reactor equipment - Google Patents

Description

  BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a heat resistant material provided in a molten core holding device installed in a reactor containment vessel.

  In the reactor containment vessel provided in the nuclear power plant, for example, when the piping connected to the reactor pressure vessel is broken, the emergency core cooling system is activated to supply cooling water and the core is cooled. . However, it is assumed that core cooling is insufficient due to startup failure of the emergency core cooling system, etc., and high temperature core melt drops from the reactor pressure vessel to the floor of the reactor containment vessel. It is necessary to take all possible safety. Even if the core melt falls to the floor surface, if the coolant is subsequently injected properly, the core melt is cooled by the coolant, but in case the injection of the coolant is delayed, the core melt It is necessary to take measures against the erosion of concrete on the floor due to

  Therefore, a method has been proposed in which a molten core holding apparatus equipped with a high melting point heat resistant material is disposed on the floor surface of the reactor containment vessel, and core molten material falling from the reactor pressure vessel is received (Patent Document 1 etc. reference).

JP 2014-62859 A

The heat-resistant material, W metal material or the like Al203, MgO, ceramic material such as ZrO ₂ is applied. The ceramic material has a melting point of 2000 ° C. or more and satisfies the required performance as a heat-resistant material. On the other hand, when a ceramic material is applied to the heat-resistant material, the ceramic material is once molded and sintered to form a block to form a heat-resistant block, which is disposed in the reactor containment vessel. The size of the heat-resistant block is limited in consideration of ease of handling and workability. In this case, the heat-resistant material is formed by arranging and laminating a large number of heat-resistant blocks.

  The gaps formed between the heat-resistant blocks are usually filled with a powdery joint material of the same material as the heat-resistant blocks. However, since the joint material has a lower density and lower erosion resistance than the heat-resistant block, it is more likely to be corroded by the core melt than the heat-resistant block.

  Therefore, in a heat-resistant material in which layers (heat-resistant layers) formed by arranging heat-resistant blocks regularly in the horizontal direction are stacked vertically, two joint materials facing each other vertically easily overlap linearly. Where the joint material overlaps the upper and lower portions, the erosion rate of the core melt may be faster than the other portions (hereinafter, the portions where the joint materials overlap vertically are referred to as erosion channels), and the joint material overlaps the upper and lower portions. If there are many spots, the area of the erosion channel will increase.

  The present invention is made in view of the above, and an object of the present invention is to provide a heat resistant material capable of reducing the area of the erosion channel and suppressing the erosion of the core melt.

To achieve the above object, the present onset Ming are those in which the first heat-resistant layer formed by arranging a plurality of heat-proof blocks in the horizontal direction, are laminated on the upper side of the first heat-resistant layer, forming the first heat-resistant layer And a second heat-resistant layer in which a plurality of heat-resistant blocks identical to each other are arranged in the horizontal direction, the heat-resistant material being disposed on the floor of the reactor containment vessel and constituting the core melt holding device In the second heat resistant layer, a plurality of linear rows formed by arranging the heat resistant block in the long side direction of the heat resistant block are arranged in the short side direction of the heat resistant block, and the lengths are adjacent to each other in the short side direction The arrangement of the heat-resistant blocks is formed by shifting the arrangement of the heat-resistant blocks by a half pitch in the side direction, the pitch of the arrangement of the heat-resistant blocks in the long side direction in the first heat-resistant layer and the second heat-resistant layer is L, the short side direction Arrangement of the heat-resistant block of When the heat resistance is l, the second heat resistant layer is l / 4 in the short side direction of the heat resistant block, L / 4 in the long side direction of the heat resistant block, and the heat resistance to the first heat resistant layer The arrangement of the blocks is shifted, and the joints between the heat-resistant blocks adjacent in the horizontal direction in the second heat-resistant layer are linear with the joints in the heat-resistant blocks adjacent in the horizontal direction in the first heat-resistant layer It is characterized in that it is configured not to overlap.

  According to the present invention, it is possible to provide a refractory material capable of reducing the area of the erosion channel and suppressing the erosion of the core melt.

BRIEF DESCRIPTION OF THE DRAWINGS It is a longitudinal cross-sectional view showing schematic structure of one structural example of reactor installation which applies the core meltdown holding apparatus provided with the heat-resistant material which concerns on 1st Embodiment of this invention. It is a top view which shows a part of heat-resistant material with which the molten core holding device concerning a 1st embodiment of the present invention is provided. It is the elements on larger scale which expanded the part III of FIG. It is a top view which shows a part of heat-resistant material of a comparative example. It is a top view which shows a part of heat-resistant material which concerns on 2nd Embodiment of this invention. It is a top view which shows a part of heat-resistant material which concerns on 3rd this embodiment of this invention. It is a side view of FIG. It is a top view which shows the 2nd heat resistant block which concerns on 4th Embodiment of this invention. It is a side view of FIG.

First Embodiment
(Constitution)
1. Reactor Facility FIG. 1 is a longitudinal cross-sectional view showing a schematic configuration of a configuration example of a reactor facility to which a molten core holding device provided with a heat-resistant material according to the present embodiment is applied.

  As shown in FIG. 1, a reactor pressure vessel 2 is stored in a reinforced concrete reactor containment vessel 1 lined with a steel liner. The reactor pressure vessel 2 accommodates a core 3 holding the fuel of the reactor.

  The reactor containment vessel 1 is formed in a cylindrical shape so as to be airtight. In the reactor containment vessel 1, an upper dry well 4A, a lower dry well 4B, a suppression chamber 5 and the like surrounding the reactor pressure vessel 2 and the like are provided.

  The upper dry well 4A is provided so as to surround the side surface of the reactor pressure vessel 2. The lower dry well 4 </ b> B is provided below the reactor pressure vessel 2 and accommodates, for example, equipment for operating control rods for controlling the core 3 in the reactor pressure vessel 2. The suppression chamber 5 is provided below the upper dry well 4A so as to surround the lower dry well 4B. The upper dry well 4A, the lower dry well 4B and the suppression chamber 5 are partitioned by a reinforced concrete diaphragm floor 6. Lower dry well 4B and suppression chamber 5 are partitioned by dry well wall surface (side wall surface) 8 standing upward from the floor surface (pedestal floor) 7 formed at the bottom of reactor containment vessel 1 . The dry well wall 8 is joined to the end of the diaphragm floor 6 and supports the reactor pressure vessel 2. A molten core holding device 9 is disposed on the floor 7 of the reactor containment vessel 1.

2. Core Melt Holding Device The core melt holding device 9 is disposed below the reactor pressure vessel 2 so as to face the bottom of the reactor pressure vessel 2. The core melt holding device 9 is provided with a heat resistant material 10 in which heat resistant layers are stacked vertically. As described above, the core melt holding apparatus 9 is provided in case of an unexpected situation where the high temperature core melt 11 leaks from the reactor pressure vessel 2 due to a failure of the emergency core cooling system or the like. It has a function of receiving, holding, and cooling the core melt 11 falling from the reactor pressure vessel 2 for the purpose of ensuring complete safety. In the present embodiment, the molten material dropped from the reactor pressure vessel 2 onto the molten core holding device 9 is referred to as a core molten material (debris) 12.

  FIG. 2 is a top view showing a part of the heat-resistant material 10 provided in the molten core holding device 9 according to the present embodiment. As shown in FIG. 2, the heat-resistant material 10 according to this embodiment includes a first heat-resistant layer 13 and a second heat-resistant layer 14 laminated on the upper side of the first heat-resistant layer 13.

  The first heat resistant layer 13 is formed by arranging the first heat resistant blocks 13A on the floor surface 7 of the reactor containment vessel 1 at intervals in the horizontal direction (vertical and horizontal directions in FIG. 2). Specifically, in the present embodiment, the plurality of first heat-resistant blocks 13A are formed in a rectangular parallelepiped shape, and the first heat-resistant layer 13 is formed in one horizontal direction (in the present embodiment, the first heat-resistant blocks 13A). Rows formed by arranging in a straight line in the long side direction of the heat-resistant block 13A are arranged in the other horizontal direction (in the present embodiment, in the short side direction of the first heat-resistant block 13A). In the adjacent rows, the arrangement of the first heat-resistant blocks 13A is shifted by a half pitch in one horizontal direction. A joint 13B is formed between the first heat-resistant blocks 13A adjacent in one horizontal direction and the other direction. The joint 13B is a joint of adjacent first heat resistant blocks 13A, and when the first heat resistant blocks 13A are in contact with each other (when the distance between adjacent first heat resistant blocks 13A, that is, when the width of the joint 13B is zero), There are cases where a gap is present between the heat resistant blocks 13A (when the width of the joint 13B is greater than zero). The present embodiment exemplifies the case where there is a gap, and the gap is filled with, for example, the powdery joint material 13E of the same material as the first heat resistant block 13A.

  The second heat-resistant layer 14 is formed by arranging the second heat-resistant blocks 14A horizontally in the horizontal direction on the first heat-resistant blocks 13A. Specifically, in the present embodiment, the plurality of second heat-resistant blocks 14A are formed in a rectangular shape having the same size as the first heat-resistant blocks 13A, and the second heat-resistant layer 14 horizontally extends the second heat-resistant blocks 14A. Rows formed linearly in one direction are formed side by side in the other horizontal direction. In the adjacent rows, the arrangement of the second heat-resistant blocks 14A is shifted by a half pitch in one horizontal direction. A joint 14B is formed between the second heat-resistant blocks 14A adjacent in one horizontal direction and the other direction. The joint 14B is a joint of the adjacent second heat resistant blocks 14A, and there are cases where the second heat resistant blocks 14A are in contact with each other and a gap is interposed between the second heat resistant blocks 14A. The present embodiment exemplifies the case where a gap intervenes, and the gap is filled with, for example, a powdery joint material 14E made of the same material as the second heat-resistant block 14A. In this embodiment, the width of the joint 13B extending in one horizontal direction and the width of the joint 13B extending in the other horizontal direction are illustrated as an example, but the widths may be different. The same applies to the joint 14B.

  Although the second heat resistant layer 14 may be directly placed on the first heat resistant layer 13, in the present embodiment, a joint material is also interposed between the first heat resistant layer 13 and the second heat resistant layer 14.

  FIG. 3 is a partially enlarged view of a portion III of FIG. As shown in FIG. 3, in the plurality of second heat-resistant blocks 14A, the joints 14B of adjacent ones basically do not linearly overlap with the joints 13B of the plurality of first heat-resistant blocks 13A when viewed from above (That is, the joints 13B and 14B intersect). Hereinafter, the arrangement method of the 2nd heat-resistant block 14A is demonstrated.

  In the following description, the length in one horizontal direction of the first and second heat resistant blocks 13A and 14A is a, the length in the other horizontal direction of the first and second heat resistant blocks 13A and 14A is c, and the first and second heat resistant blocks 13A , 14A, width b of joint 13B, 14B, pitch L of first heat resistant block 13A in horizontal direction and in other direction, length D of second heat resistant block 14A in horizontal direction and direction D, d Do. The pitch L is the length a plus the length b. The pitch l is the length c plus the length b.

  The shift length D of the second heat resistant block 14A in one horizontal direction is the shift amount in one horizontal direction of the corresponding portion with the first heat resistant block 13A having the largest overlapping area (for example, the first and second heat resistant blocks 13A and 14A The distances between the corresponding short sides 13C and 14C). The shift length d of the second heat resistant block 14A in the other horizontal direction is the shift amount in the other horizontal direction of the corresponding portion with the first heat resistant block 13A having the largest overlapping area (for example, the first and second heat resistant blocks 13A, A distance between the corresponding long sides 13D and 14D of 14A.

  In the present embodiment, the second heat resistant block 14A is disposed on the first heat resistant block 13A such that the shift length D in one horizontal direction of the second heat resistant block 14A is larger than 0 and smaller than L / 2. Further, the shift length d in the other horizontal direction of the second heat-resistant block 14A is also larger than 0 and smaller than l / 2. In addition, it is necessary to make the shift lengths D and d larger than the width b of the joint 13B between the first heat resistant blocks 13A, and in this embodiment, they are L / 4 and l / 4, respectively.

  In the present embodiment, the core melt holding device 9 is exemplified to include two heat resistant layers, the first heat resistant layer 13 and the second heat resistant layer 14, but three or more core melt holding devices 9 are provided. A heat resistant layer may be provided. When the molten core holding device 9 includes three or more heat resistant layers, the heat resistant layer may be stacked on the second heat resistant layer 14 in accordance with the above-described arrangement method.

  Similarly, when the first heat resistant blocks 13A and the second heat resistant blocks 14A are in contact with each other, the shift length D is larger than 0 and smaller than a / 2, and the shift length d is larger than 0 and a / It may be made smaller than 2.

(Operation)
When the core melt 12 falls from the reactor pressure vessel 2, the core melt 12 received by the heat resistant material 10 of the core melt holding device 9 is, for example, the upper portion by the cooling water injected into the lower dry well 4B. It is cooled from Thereafter, the heat possessed by the core melt 12 decays with the passage of time, and the core melt 12 solidifies on the refractory material 10.

(effect)
(1) The inventors of the present invention have conducted intensive studies, and since the joint material of the core melt holding device has a lower density than the heat-resistant block, even if the material is the same material, it erodes the core melt compared to the heat-resistant block. It was newly discovered that it was easy to

  FIG. 4 is a top view showing a part of the heat-resistant material of the comparative example. In FIG. 4, portions equivalent to the heat-resistant material 10 of the first embodiment are given the same reference numerals, and the description will be appropriately omitted. As shown in FIG. 4, in the heat resistant material 100 of the comparative example, when the second heat resistant layer 14 is viewed from above, the shift length D of the second heat resistant block 14A in one horizontal direction with respect to the first heat resistant block 13A is L It is arranged to be / 2. In that case, when the second heat resistant block 14A is shifted in the other horizontal direction with respect to the first heat resistant block 13A, the upper and lower joints 13B and 14B linearly overlap, and a large number of erosion channels 16 with a large area are generated.

  On the other hand, in the present embodiment, temporarily, due to the water injection delay in the lower dry well 4B, a part of the core melt 12 corrodes the joint 14B of the second heat resistant layer 14 and flows downward between the second heat resistant blocks 14A. Also, since the joints 13B and the joints 14B do not overlap linearly, the core melt 12 reaches the first heat-resistant block 13A of the first heat-resistant layer 13 without entering the joint 13B for the most part. . In addition, since the area where the joints 13B and 14B overlap and overlap is small, the core melt 12 also has tension, and the core melt 12 does not easily penetrate. Therefore, the core melt 12 remains on the first heat resistant layer 13 and is gradually cooled by the cooling water injected late into the lower dry well 4 B, and solidifies before reaching the floor surface 7 of the reactor containment vessel 1. Do. Thus, the area of the erosion channel formed in the heat-resistant material 10 can be reduced, and the erosion of the core melt 12 can be suppressed.

  (2) In the present embodiment, the second heat resistant block 14A is disposed on the first heat resistant block 13A while being shifted in one horizontal direction with respect to the first heat resistant block 13A. Therefore, the total length of joints from the upper surface of the second heat resistant block 14A to the lower surface of the first heat resistant block 13A (that is, the floor surface 7 of the reactor containment vessel 1) can be lengthened. Therefore, it is advantageous in that core melt 12 invading joints 13B and 14B of first and second heat resistant blocks 13A and 14A can be cooled by cooling water and solidified before reaching core surface 12. It is.

  (3) The present embodiment is an example in which the formation is shifted by L / 2 in the first and second heat resistant layers 13 and 14. Therefore, by setting 0 <D <L / 2, the upper and lower joints 13B and 14B are linear. While overlapping can be avoided, a portion where the flow path becomes long between the first heat-resistant layer 13 and the second heat-resistant layer 14 (the distance in the horizontal direction between the joints 13B and 14B exceeds L / 2) It can be made. Also, for convenience, the joint 13B between the first heat resistant blocks 13A adjacent in one horizontal direction in the first heat resistant layer 13 is a first short side joint, and the second heat resistant block 14A adjacent in one horizontal direction in the second heat resistant layer 14 Assuming that the joint 14B is referred to as a second short side joint, in the case of D = L / 4, the two first heat resistant blocks 13A straddling the second short side joint from the second short side joint The shortest distance to the first short side can be made equal. In this case, it is useful for flexibly absorbing the arrangement error of the first and second heat resistant blocks 13A and 14A arranged in large numbers in the horizontal direction, and for avoiding the occurrence of the linear overlap of the joints 13B and 14B.

Second Embodiment
(Constitution)
FIG. 5 is a top view showing a part of the heat-resistant material 20 according to the present embodiment. In FIG. 5, the same parts as those of the heat-resistant material 10 of the first embodiment are given the same reference numerals, and the description thereof will be omitted as appropriate.

  As shown in FIG. 5, in the heat-resistant material 20 according to this embodiment, the second heat-resistant block 24A of the second heat-resistant layer 24 is formed larger in the horizontal direction than the first heat-resistant block 13A of the first heat-resistant layer 13. And the heat resistant material 10 of the first embodiment. The other configuration is the same as that of the heat-resistant material 10 of the first embodiment. In the present embodiment, the second heat-resistant block 24A is preferably formed to satisfy (NL−b) × (Nl−b) (where N is an integer). This is because it is possible to prevent the upper and lower joints 13B and 24B from linearly overlapping in consideration of the repetition of the arrangement pattern in the horizontal direction. In this embodiment, the case where the size in the horizontal direction of the second heat resistant block 24A is (2L−b) × (2I−b) is illustrated. In addition, in this embodiment, the case where the 1st heat-resistant layer 13 and the 2nd heat-resistant layer 14 are arranged straight in a horizontal direction, and joints 13B and 14B are made into lattice shape is illustrated.

  In the present embodiment, at least one corner portion 25 of the second heat-resistant block 24A is positioned at the center of the first heat-resistant block 13A of any of the plurality of first heat-resistant blocks 13A partially overlapping in the vertical direction, as viewed from above. Thus, the second heat resistant block 24A is disposed on the first heat resistant block 13A.

(effect)
In the present embodiment, since the second heat-resistant block 24A is formed to be larger in the horizontal direction than the first heat-resistant block 13A, the portion where the upper and lower joints overlap can be reduced. As such, the area of the erosion channel 16 can be reduced and the erosion of the core melt 12 can be suppressed, as compared to the first embodiment.

  With respect to the plurality of (three in the present embodiment) first heat-resistant blocks 13A covered by the second short-side joints described above, arranging the second short-side joints at the center of one horizontal direction of the first heat-resistant blocks 13A it can. Therefore, the distance from the second short side joint to the first short side joint can be made equal. Moreover, since there is no inclination in the distance from the second short side joint to the first short side joint, the arrangement error of the first heat resistant block 13A and the second heat resistant block 24A is absorbed, and the linear overlap of the joints 13B and 24B Can be avoided. Strictly speaking, in order to obtain this effect, the apex of a virtual quadrilateral obtained by enlarging the horizontal surface of the second heat-resistant block 24A by b / 2 on both sides in one horizontal direction and both sides in the other horizontal direction is the center of the first heat-resistant block 13A. It is preferable to arrange so as to come to That is, in this embodiment, the center of the intersection of the joints 24B is disposed at the center of the first heat-resistant block 13A.

Third Embodiment
(Constitution)
FIG. 6 is a top view showing a part of the heat-resistant material according to the present embodiment, and FIG. 7 is a side view of FIG. In FIGS. 6 and 7, parts equivalent to the heat-resistant material 10 of the first embodiment are given the same reference numerals, and the description thereof will be omitted as appropriate.

  As shown in FIGS. 6 and 7, the heat-resistant material 30 according to the present embodiment integrally integrates the second heat-resistant block 14A with the largest one of the first heat-resistant blocks 13A partially overlapping vertically. It differs from the heat-resistant material 10 of the first embodiment in that it is formed and arranged side by side in the horizontal direction. Of course, the relationship between the pitches L and l, the lengths a and c, and the shift lengths D and d are the same as in the first embodiment. Therefore, it can be said that the first and second heat resistant layers 13 and 14 in the present embodiment are obtained by arranging one block obtained by integrally molding each one heat resistant block 13A and 14A in the horizontal direction via 13B and 14B. As a result, the configuration of the heat-resistant material 30 is substantially the same as the heat-resistant material 10 of the first embodiment, except that no joint material intervenes between the first and second heat-resistant layers 13 and 14. It goes without saying that a layer equivalent to two layers consisting of the first and second heat resistant layers 13 and 14 can be further laminated. In that case, the stacked layers can be shifted according to the first embodiment.

(effect)
According to the above-described configuration, in the present embodiment, the following effects can be obtained in addition to the effects obtained in the first embodiment described above.

  In the present embodiment, the second heat-resistant block 14A is integrally formed with the one of the first heat-resistant blocks 13A that partially overlaps vertically, with the largest overlapping area. Therefore, the heat-resistant layer having the same structure as the heat-resistant material 10 of the first embodiment can be obtained only by arranging the integrally formed heat-resistant blocks on the floor surface 7 of the reactor containment vessel 1. Therefore, the operation of laminating the second heat resistant block 14A on the first heat resistant block 13A can be omitted, and the working efficiency can be improved. Further, the point where no joint material intervenes between the first and second heat resistant layers 13 and 14 also advantageously acts to suppress the erosion of the core melt 12.

Fourth Embodiment
(Constitution)
FIG. 8 is a top view showing a second heat-resistant block according to the present embodiment, and FIG. 9 is a side view of FIG. In FIGS. 8 and 9, parts equivalent to the second heat-resistant block 14A of the first embodiment are given the same reference numerals, and the description thereof will be omitted as appropriate.

  As shown in FIGS. 8 and 9, the heat-resistant material of the present embodiment is the heat-resistant material of the first embodiment in that the second heat-resistant block 34A is formed in a shape in which the upper surface and the lower surface are shifted as viewed from above. Different from material 10 That is, this embodiment is an example in which the second heat-resistant layer is formed of the second heat-resistant block 34A. The other configuration is the same as that of the heat-resistant material 10 of the first embodiment.

  In the following description, the shift length of the upper surface of the second heat-resistant block 34A in one horizontal direction is E. The displacement length E of the upper surface of the second heat-resistant block 34A in one horizontal direction is the distance between the shorter side 34C of the lower surface of the second heat-resistant block 34A and the shorter side 34C 'of the upper surface. The plane X is a plane (inclined plane) including the short sides 34C and 34C '. In the present embodiment, the upper and lower surfaces of the second heat-resistant block 34A are formed in the same shape and size. Therefore, the second heat-resistant block 34A of the present embodiment viewed from the side is formed in a parallelogram. In the present embodiment, the second heat-resistant block 34A is formed so that the deviation length E is larger than 0 and smaller than L / 2. When laminating the second heat resistant block 34A on the first heat resistant block 13A (see FIGS. 2 and 3), the lower side of the joint 34B between the second heat resistant block 34A and the upper side of the joint 13B between the first heat resistant block 13A Should not overlap linearly.

(effect)
According to the above-described configuration, in the present embodiment, the following effects can be obtained in addition to the effects obtained in the first embodiment described above.

  In the present embodiment, the second heat-resistant block 34A is formed in a shape in which the upper surface is shifted in one horizontal direction. Therefore, as compared with the case where the second heat-resistant block 34A is formed in a rectangular parallelepiped shape, the flow path (the upper and lower length of the joint 34B) extending between the adjacent second heat-resistant blocks 34A is longer because the joint 34B is inclined. And the erosion of the core melt 12 can be further delayed.

  In the embodiment, the upper surface of the second heat-resistant block 34A is shifted in one horizontal direction, but in addition to this, the upper surface of the second heat-resistant block 34A may be shifted in the other horizontal direction. In this case, the flow path can be made longer and more complicated as compared with a configuration in which the upper surface of the second heat resistant block 34A is shifted in one horizontal direction. Moreover, although the case where the upper surface of the 2nd heat resistant block 34A was shifted to one horizontal direction was illustrated in this embodiment, the upper surface of the first heat resistant block 13A may be shifted to one horizontal direction, and the first heat resistant block The upper surfaces of the 13A and the second heat-resistant blocks 34A may be shifted in one horizontal direction. When both the first heat-resistant block 13A and the second heat-resistant block 34A are shifted in one horizontal direction and in the other direction, the joints 13B and 34B naturally shift even if the upper and lower blocks are stacked horizontally.

<Others>
The present invention is not limited to the above-described embodiments, and includes various modifications. For example, the above-described embodiment is described in detail to explain the present invention in an easy-to-understand manner, and is not necessarily limited to one having all the described configurations. For example, part of the configuration of one embodiment may be replaced with the configuration of another embodiment, or part of the configuration of each embodiment may be deleted.

  In each embodiment mentioned above, the case where it applied to the fusion material holding device 9 arranged on the floor 7 of the nuclear reactor containment vessel was illustrated. However, the essential effect of the present invention is to provide a heat resistant material capable of reducing the area of the erosion channel and suppressing the erosion of the core melt, and as far as this essential effect is obtained, the struts and the pool The present invention can also be applied to a molten core holding apparatus provided with cooling pipes and the like.

  Further, in the embodiment described above, the case of 0 <D <L / 2 and 0 <d <l / 2 is illustrated. However, as long as the essential effect of the present invention described above is obtained, D = L / 2 and d = 1/2 may be set depending on the arrangement of the first and second heat resistant blocks 13A and 14A.

Reference Signs List 1 reactor containment vessel 2 reactor pressure vessel 3 core 9 core melt holding apparatus 10 heat resistant materials 13 and 14 first and second heat resistant layers 13A and 14A first and second heat resistant blocks 13B and 14B joint 25 corner portion L pitch D offset length

Claims (2)

A first heat-resistant layer formed by arranging a plurality of heat-proof blocks in the horizontal direction,
The laminated on the upper side of the first heat-resistant layer, and a second heat-resistant layer arranged plurality of the first constitutes the heat-resistant layer and the same heat block in the horizontal direction,
In the heat resistant material disposed on the floor surface of the reactor containment vessel and constituting the molten core holding device,
In the first heat resistant layer and the second heat resistant layer, a plurality of linear rows formed by arranging the heat resistant block in the long side direction of the heat resistant block are arranged in the short side direction of the heat resistant block and in the short side direction The heat-resistant blocks are formed by shifting the arrangement of the heat-resistant blocks by half a pitch in the long side direction between adjacent rows,
When the pitch of the arrangement of the heat resistant blocks in the long side direction in the first heat resistant layer and the second heat resistant layer is L and the pitch of the arrangement of the heat resistant blocks in the short side direction is l, the second heat resistant layer The arrangement of the heat-resistant block is shifted relative to the first heat-resistant layer by 1/4 in the short side direction of the heat-resistant block, by L / 4 in the long side direction of the heat-resistant block,
As viewed from above , joints between heat-resistant blocks adjacent in the horizontal direction in the second heat-resistant layer are configured so as not to overlap linearly with joints in the heat-resistant blocks adjacent in the horizontal direction in the first heat-resistant layer . Heat resistant material characterized by The core,
A reactor pressure vessel containing the core;
A reactor containment vessel storing the reactor pressure vessel ;
Reactor facility, characterized in that a core catcher device comprising a heat-resistant material according to 請 Motomeko 1.

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