TW476072B - An absorbing rod, an apparatus for inserting the absorbing rod, a cask, and a method of storing spent fuel assemblies - Google Patents

Description

Printed by the Employees' Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 476072 A7 B7____ V. Description of the invention (1) The scope of the invention: The present invention relates to an absorber rod with neutron absorption capability for insertion into a control rod catheter in a used fuel assembly, an insert The device is used for inserting an absorber rod into a control rod catheter, a container for containing, transporting and storing the used fuel assembly, and a method for transporting and storing the used fuel assembly. BACKGROUND OF THE INVENTION Consumed fuel assemblies that cannot be used in the final stages of the fuel cycle are referred to as used fuel assemblies. The used fuel assembly contains fission products and other highly radioactive materials, and must be cooled by heat and cooled in a cooling pond for nuclear power plutonium for a period of time. It is then sent to a sheltered container called a take-up container, and transported and stored in a reprocessing plant or storage facility by truck or ship. When reprinted, the fuel assembly is used to load the container. A support element with a grid is called a basket. Each used fuel assembly is placed in one of the storage rooms composed of several storage spaces in the basket, and the appropriate support strength is ensured to withstand the vibrations during transportation. Various types of receptacles have been disclosed in publications such as 'Atomic Exposure' (Nikkan Kogyo Shuppan Production, April 1, 1998) and Japanese Patent Application Publication No. 62-242725. Figure 13 is a perspective view of an example of a container. Fig. 14 is an axial sectional view of the container shown in Fig. 13. The container 500 includes a main body 501, a neutron shielding resin 502 placed on the outer circumference of the main body 501, an outer tube 503, a bottom 504, and a cover 505. The main body 501 and the bottom 504 are r-ray shielding materials made of carbon steel. The cover 505 is composed of a main cover 506 made of stainless steel and a second cover 507. The main body 501 and the bottom 504 are -4- This paper size applies to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) ------ 丨 Order ------ I — (Please read the back (Please fill in this page again)

476072 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs Α7 Β7 V. Description of the invention (2) Butt welding connection. The main cover 506 and a second cover 507 are connected to the main body 501 with stainless steel screws. An O-ring is placed between the cover 505 and the main body 501 to keep airtight inside. Between the main body 501 and the outer tube 503 there are many inner fins 50 $ for heat conduction. The inner fins 508 are made of copper to enhance the thermal conductivity. The liquid resin 502 is injected into the space formed by the inner fins 508, and is cured by a thermosetting reaction. The blue 509 is a tube bundle structure composed of 69 square tubes 510 as shown in FIG. 14 and inserted into a recess 511 in the main body 501. The square tube 510 is made of an aluminum alloy mixed neutron absorbing material (boron: b) so that the used fuel assembly inserted cannot reach a critical state. On both sides of the container main body 512, there are provided lugs 513 (only one is shown) for hanging the container 500. A buffer material 514 is provided at both ends of the container body 512 and is composed of wool or other impact resistant material (only one end is shown). Reference number 515 is one of the storage rooms for the used fuel assembly. The light water reactor is divided into a boiling water reactor (BWR) and a pressurized water reactor (PWR). The harvester 500 is a collection container used by the BWR to store the used fuel assembly. The structure of BWR's fuel assembly is shown in Figure 15. bwr's fuel assembly has a 4-slot box 601 in a grid configuration, in which a cross-shaped control rod 608 is placed, and the reactivity of the fuel rod 603 is controlled by the vertical movement of the control rod 608. The fuel assembly 600 has an 8 × 8 fuel rod 603 in a grid configuration. Each fuel rod 603 is a 4 meter long rod. A support grid 607 is used to support the fuel rod 603. In each of the fuel rods 603, a plurality of cylindrical pellets 631 are made of sintered uranium oxide powder and are inserted as a fuel into a 55-gold composite tube 633, and are inserted into the composite tube 633 by a spring M]. The first handle 610 is used to raise and lower the fuel collection. The paper size is applicable to the τ _ house standard (CNS) A4 specification (χ Norwegian ------- ----- installed ------- order ---- ------ line (Please read the notes on the back before filling this page) 〆-5-Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 476072 A7 _B7_____ V. Description of Invention (3) Body 600. Insert this receipt The used fuel assembly in the storage chamber 515 of the container 500 is a fuel assembly 600 for BWR 600 as shown in Fig. 15. In contrast, the fuel assembly system shown in Fig. 16 is used for PWR. The fuel assembly 700 and the control rods 708 are appropriately distributed in the fuel rod 703, and the fuel rods 703 and the control rods 708 are arranged in a 1 7 X 1 7 grid type. In this 1 7 X 1 7 fuel assembly 700, a measuring tube It is placed in the center and distributed with 24 control rods 708. The reactivity of the reactor can be controlled by moving the control rods 708 up or down. Each fuel rod 703 is about 4 meters long and is the same as the BWR fuel rod 603, so a support grid is provided. The grid 707 is used to support the fuel rod 703. In each fuel rod 703, a plurality of core blocks 731 are inserted into a hammer-plated alloy 733 composite tube, and a spring 73 2 Hold the upper part of the inserted composite pipe 733. In the receiving container, 70 units of the used fuel assembly are placed in the storage room. Figure 17 is an axial sectional view of the PWR receiving container. As shown in Figure 17, A recess 811 of the PWR container 800 accommodates a basket 809 of a storage chamber 815 with a rectangular cross-section formed by interactive radial bonding plates 817. Each plate 817 is made of aluminum alloy mixed B as a neutron absorbing material, and the square of the BWR The mold tube 510 is the same. However, each plate 817 has a through-hole cooling water passage 816 extending in the axial direction, which is called a water zone. When the used fuel assembly is cooled, each basket storage chamber and this through system are filled with water to slow down. Neutrons cause neutrons to be effectively absorbed by the plate 817 and resin 802. After a certain cooling period, the water in the cooling water passage is drained and the passage is dried. The cooling water passage 816 is necessary because the concentration of uranium in the fuel assembly of PWR is more than that of BWR The factors of the fuel assembly are high, the amount of uranium added per fuel assembly is large, the cross-sectional area of the fuel assembly is wide, and the configuration of this assembly is -6- This paper scale applies to China National Standard (CNS) A4 specifications (210 X 297 mm 5 ~ (please Read the back of the precautions to fill out this page)

Install -------- order --------- line I 476072 ΚΙ Β7 ____ V. Description of the invention (4) (Please read the precautions on the back before filling this page) The system is highly responsive . The distance dd shown in FIG. 17 is a distance to ensure a subcritical state of the used fuel assembly. PWR requires a longer distance than BWR. The storage chamber 815 is a non-grid configuration but is shifted in position to handle a PWR used fuel assembly having a wider cross-sectional area than the BWR used fuel assembly, and is effectively placed in the pocket 811. From the used fuel assembly of the above PWR, take out the control rods 708 distributed in the grid-shaped fuel rods 703, and take out the used fuel assembly 700 into which the control rods 708 are inserted, and insert and store them in the receiving container 800. The storage chamber 815 formed by the basket 809. Therefore, the control rod 708 or the measuring rod is taken out and not shown. The remaining empty space in the used fuel assembly is dead space, and it is expected that the space will be effectively used. In addition, the plates and square pipes constituting the basket for PWR must have cooling water passages 8 1 6. The structure of the plates and square pipes is more complicated than that of BWR plates and square pipes, requiring more time and labor. In addition, the cross-sectional area of the used fuel assembly of PWR is rectangular and wide, and a cooling water passage 816 is also required. Therefore, the efficiency of collecting the used fuel assembly in the container is poor. SUMMARY OF THE INVENTION The employee's cooperative of the Jiji Village Intellectual Property Bureau manufactures an object of the present invention to provide an absorber rod capable of improving the storage density of a fuel assembly that has been used. The use of a control rod and a measuring rod to effectively insert PWR is completed. The existing space of the fuel assembly is shortened by a distance dd to ensure a subcritical state in the used fuel assembly, and an insertion device, a container receiving method, and a method for transporting and storing the used fuel assembly. This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) A7 ----- · ---- 67 V. Description of the invention (5) The absorption rod according to a feature of the present invention has almost the same performance as PWR. 4 cylindrical rod-like shapes. In addition, the absorption rod has the ability to shield neutrons. Because the absorption rod has almost the same cylindrical control as that used for PWR, this type of absorption rod can be inserted into the control rod capture tube of the used fuel assembly and the measurement tube or control rod conduit in the fuel assembly including the measurement tube. According to another feature of the present invention, the absorbing rod is made of an aluminum composite material or an aluminum alloy powder having a small force and a boron or boron compound powder capable of absorbing neutrons and an aluminum or aluminum alloy powder. Because the absorbent rod is made of this material, it will not be damaged by small impacts during transportation. As a result, the neutron absorption capacity can be maintained even during transportation. For example, it is safer and more ideal than an absorbent rod structure in which boron powder is filled in a tube. According to still another feature of the present invention, the container includes a group of absorbing rods having a shape almost the same as that of a cylindrical control rod for PWR. In addition, the absorbing rod group has the ability to shield neutrons. Store the used fuel assembly 2 in the container. Therefore, the number of neutrons emitted from the used fuel assembly can be reduced. In addition, the interval between the used fuel assemblies can be shortened. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs \ The insertion device according to the present invention includes a position detector to detect the distance between the through-hole group of the conductor and the control rod duct group of the fuel assembly of J Bi relative position. In addition, the absorption rods are lowered so that the through-hole group is used as a guide hole, and the long absorption rod group can be inserted into a control rod catheter or a control rod catheter including a measuring tube. According to still another feature of the present invention, the method of transporting and storing the used fuel assembly includes a step of inserting an absorbent rod group, and the absorption standard of the paper is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) 476072 A7 B7 V. Description of the invention (6) The rod group has almost the same shape as the cylindrical control rod used for the reaction control of the reactor reactor, and has the ability to shield neutrons. Insert a control rod The catheter group includes the measuring tube of the used fuel assembly of PWR. In addition, the used fuel assembly for transporting PWR is stored in a state in which an absorber rod group is inserted. Therefore, the distance between the used fuel assemblies can be drawn short. Other objects and features according to the present invention will be apparent from the following description and with reference to the accompanying drawings. Brief Description of the Drawings Figure 1 is an inter-body diagram showing the structure of the fuel assembly used by PWR. Fig. 2 is a view showing the structure of the absorbent rod block inserted into the used fuel assembly and explaining how the absorbent rod block is inserted into the used fuel assembly. Fig. 3 is a plan view of a fuel assembly using Bi; Fig. 4 is a sectional view taken along line a-A of the supporting grid. FIG. 5 is a view showing the configuration of a fuel rod. Fig. 6 is a radial cross-sectional view showing the configuration of a container according to the present invention. Fig. 7 is a view showing the configuration of an insertion device according to the present invention. Fig. 8 is a sectional view taken along line B-B of the lower end plate. Figures 9 A-9 C are examples of photographs. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs Figure 10 is a view showing the insertion device after the insertion is completed. Fig. 11 is a view showing the structure of the used fuel assembly and the structure of a hanger after the insertion is completed. Fig. 12 is a schematic diagram showing the storage arrangement of the used fuel assembly in the storage tank. This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) 476072 A7 ---- ^ -—__— B7 __ V. Description of the invention (7) Figure 13 is a perspective view showing the BWR container structure. FIG. 14 is a radial cross-sectional view showing the container receiving structure shown in FIG. 3. Figures 15 (a), (b), and (c) are schematic diagrams showing the structure of the fuel assembly of bwR. Figures 16 (a), (b), and (c) are schematic diagrams showing the structure of the fuel assembly of PWR. FIG. 17 is a radial cross-sectional view showing the structure of a conventional pwR container. Detailed description and reference of the preferred embodiment of the preferred embodiment of the absorber rod, the insertion device (the device for inserting the absorber rod), the method of transporting and storing the used fuel assembly according to the present invention The drawings are as follows. However, the present invention is not limited to these specific embodiments. The used fuel assembly in accordance with the present invention is preferentially explained. Fig. 1 is a perspective view showing the shape and structure of the fuel assembly of PWR. As shown in FIG. 1, a fuel assembly 1 is a used fuel assembly, which forms a grid-shaped fuel rod bundle 4, a control rod duct 5, and a measurement tube 6, which are arranged as j 4 χ i 4 thumbs. Grid section. This grid arrangement is supported by a support grid 7 located at an appropriate position in the longitudinal direction of the fuel rod 4, a control rod duct 5, and a measuring tube 6. The control rod duct 5 and the measurement tube 6 are supported by the upper nozzle 2 and the lower nozzle 3 of τ. In this way, the control rod duct 5 and the measurement tube 6 are of a cylindrical shape, and through holes are provided between the upper nozzle 2 and the lower nozzle 3 to position the control rod duct 5 and the measurement tube 6 in a grid arrangement. In the control rod conduit 5, a control rod 'having a neutron handle force absorbing the furnace and the reactivity of the reactor are controlled by the depth and number of the control rods inserted. The control rod guides 5 are dispersedly arranged in a grid arrangement. Test-10- This paper size is applicable to China National Standard (CNS) A4 (210 X 297 mm) {Please read the precautions on the back before filling this page) Order --------- Ministry of Economic Affairs Printed by the Intellectual Property Bureau employee consumer cooperative 2 07 4ί6 A7 ------___ — — V. Description of the invention (8) The measuring rod in the measuring tube 6, not shown in the figure, is regularly inserted into the reaction furnace to measure temperature and radiation Volume, and thus obtain information on response_management. However, if it is stored as a used fuel assembly, take out the control rod 'inserted into the control rod tube 5 and similarly, take out the measurement rod inserted into the measurement tube 6. Therefore, as shown in FIG. 2, a plurality of recently manufactured absorption rods have the same cylindrical shape as the control rods and measurement rods inserted into the rod-made catheter 5 and the measurement tube 6 and have the ability to absorb neutrons. The control rod duct 5 and the measurement tube 6 of the fuel assembly 1. One end of each absorbing rod 11 is connected to one end plate i 2 ′. The end plate is a rectangular plate body inserted from the opening of the upper nozzle 2, and the other end is tapered for inserting the control rod conduit 5 and the measuring tube 6. The length of the absorption rod 11 is sufficient to surround the effective length of the fuel. Upright position of the absorber rod 1 1 Table & the inner diameter of the rod guide 5 and the measuring tube 6 is ideal, as close as possible to the inner diameter of the control rod guide 5 and the measurement tube 6, but considering the length of 4 meters, it is necessary to There is considerable clearance. FIG. 3 is a plan view of the fuel assembly 1 shown in FIG. 2. The upper nozzle 2 shown in FIG. 3 is arranged relative to the grid, in which a control rod pipe 5 and a measuring tube 6 are placed. The reactor-reactor has a plurality of light water passage through holes 21. The absorption rod 11 passes through the control rod guide tube 5 and the measurement tube 6. Fig. 4 is a sectional view of the fuel assembly 1 shown in Fig. 2 taken along line a of the support grid 7. As shown in Figs. The support grid 7 supports a fuel rod 4, a control rod conduit 5 and a measuring tube 6 constituting a grid structure 14 X 14. The absorption rod 11 passes through the control rod conduit 5 and the measurement tube 6 of the support grid 7 shown in FIG. 4. Therefore, the end plate 12 shown in FIG. 2 is combined with the absorption rod 11 so that the absorption rod 11 can maintain the state of being inserted into the control rod conduit 5 and the measuring tube 6. By using combination-11-This paper size applies Chinese National Standard (CNS) A4 specification (210 X 297 mm) • ^ ------------ ^ installation (please read the precautions on the back first) (Fill in this page again) Order ---------- Line · Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs Printed by 476072 Α7 ------- Β7 (9) Description of the invention (9) The plurality of absorption rods 11 and the end plate 12 constitute an absorption rod block 10, and the plurality of absorption rods 11 can be inserted into the control rod conduit 5 and the measuring tube 6 in a batch. In addition, the end plate 1 2 is used instead of the combined absorption rod 1 1, and the absorption rod 丨 丨 can be individually inserted into the control rod conduit 5 and the measurement tube 6. However, when the fuel assembly 1 is transported, the absorber rod 1 1 is inserted therein, and it is easier to fix the absorber rod i 1 by using the absorber rod block 10. FIG. 5 is a front view of the fuel rod 4. In FIG. 5, a plurality of core blocks 3 i are inserted into a cylindrical-shaped samarium alloy composite pipe 33, and the core blocks 31 are supported by a spring 32 inserted into the upper part of the composite pipe 33. As mentioned above, the fuel rod 4 is mainly composed of the used fuel assembly. The absorber rod 1 1 is composed of composite materials or shed powder or tracer compounds with the ability to absorb neutrons, or alloy powder, and the design does not reach the critical state of the fuel assembly after use. It is ideal to use the following materials as Ming composites. In addition to adding boron powder or a compound to the aluminum composite, a third oxide can be added. Therefore, the use of mechanical alloys can increase the strength of the material. In order to achieve this goal, aluminum powder or aluminum alloy is used as a matrix material, boron or a test compound is used as a neutron absorber, and the third particle is used as an oxide, nitrate, carbide, and boride in a grinding pot. The added amount of the third pellet is ideal, and must be greater than 0% by weight and less than 30% by weight. The amount of the sample is ideal because if the amount is less than 0.01% by weight, there is no effect of increasing the strength of the material. On the other hand, if the amount is more than 30% by weight, the properties of the material are greatly reduced. In addition, it is desirable that the diameter of the third particle in the aluminum substrate is larger than 0.01 μm and smaller than 10 μm. Material diameters smaller than 0.01 μm are very expensive and difficult to obtain. On the other hand, material diameters greater than 10 μm do not help to increase material strength. -12 ¾ / δ X 1υ ζ f \ gauge 4 A 1 / n N 3 \ I-f

V. Description of the invention (彳 0) The amount of boron or traceable compounds is ideal, and must be more than 1% by weight and less than 20% by weight. Such an amount is desirable because if the amount is less than 1% by weight, neutron absorption is not good. On the other hand, if the amount is more than 20% by weight, the properties of the material are greatly reduced. In addition, it is preferable that the diameter of boron or a boron compound is larger than 0.01 μm and smaller than 100 μm. Material diameters less than 0.01 μm are very expensive. On the other hand, a material with a diameter greater than 100 μm has a reduced strength. In addition, any material having neutron-absorbing properties can be used instead of boron or a boron compound. That is, C d, Hf, or rare earth elements with large neutron absorption cross sections can be used. For example, BWR uses boron or boron compound amount, but PWR uses Ag_In_Cd compound. In the Ag-In_Cd compound, In is generally 15% by weight and Cd is 5% by weight. In addition, carbides such as Eu, Sm, and Gd can be used.

Al2O3'Zr02, S102, MgO, Ti02, and Cr203 can all be used as the third pellet. Si3N4, BN are examples of useful nitrates. Sic, wc, 0 ^ 3 are examples of useful carbides, and ZrBr2 is an example of useful borides. In addition, it is not necessary to use only the third capsule mentioned above. Any material can be used as needed. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs The following materials can be used as inscriptions or aluminum alloy powder. That is: pure Ming (Jls lxxx), Al-Cu aluminum compound (jis 2χχχ), compound (j) [s 5xxx), Al-Mg-Si aluminum compound (JIS 6XXX), A1_Zn_Mg aluminum compound (JIS 7xxx), Al -Fe aluminum compound (Fe content is 1-10% by weight). Alternatively, an Al-Mn aluminum compound (JIS 3χχχ) may be used. The materials used can be selected according to the required strength " swell " processability and temperature resistance. The powder obtained by rapid curing has a uniform and fine composition. The powder that can be used is Ming or alloy powder. Known methods such as single-roll method, double-13-476072 A7 Printed by the Consumer Cooperative of Intellectual Property Bureau of the Ministry of Economic Affairs 5. Description of invention (11) Roll method 'spray method such as air spray or gas spray can be used to obtain fast curing powder . More preferably, the aluminum or aluminum alloy powder has a diameter of 5-ΐ50 μm. If the diameter is less than 5 μηι, the particles combine together into a ball. In addition, if the diameter is less than 5, it is difficult to use the spray method (need to separate fine powder and increase coarse particles). On the other hand, if the diameter is larger than 150 μm, the spraying method is still limited, and it is difficult to mix the material with fine particles. The most ideal diameter is 50-120 pm. The cooling rate must be 102. (: / Sec. Or more. Ideally, the cooling rate must be 103 ° C / sec. Or more. On the other hand, boron or boron compounds have large characteristics of fast neutron absorption. B4C, B203 can be used in the present invention. Among them, b4c has more boron content per unit weight. Therefore, a smaller amount can absorb more neutrons. In addition, 'BW hardness is higher, so it is more ideal. The second particle mentioned above is oxidation However, other particles can be added. For example, MZr * Ti can be added to increase strength. The conditions and weights of the above mixed materials are suitable for the mechanical alloy method using a grinder. A rotary grinder can be used Or a vibrating mill instead of a grinder. If a mechanical alloy is used, aluminum and aluminum compounds are crushed by a grinding ball and become flat. In addition, the compound or compound and the third grain are ground into finer particles and uniformly enter the matrix. The flat particles are normal particle shapes containing aluminum or aluminum compounds and the third particles. It is possible to increase the strength of the material because the third particles are added and the mechanical alloy method is used. Experiments prove that the particles made by this method The material has three times higher strength than the materials made with ordinary mixers (such as cross-shaped or V-shaped mixers). (Please read the precautions on the back before filling out this page.) # 装 • II n II 1 I Order · IIIII II-14 476072 A7

5. Description of the invention (12) Outer rotten or boron compounds have high hardness and can be finely and uniformly dispersed in the matrix, which can prevent boron from sticking. In addition, the extrusion characteristics can be increased. Therefore, the extruded particles are less worn due to friction. In addition, if a third particle is added, the aluminum or aluminum compound powder will be oxidized and an oxide layer will be formed on the surface of these particles. The mechanical alloy will grind the oxide layer to a fine powder and cause the particles to be dispersed in the matrix. Oxidation of aluminum or aluminum compound powder can be accomplished by heating in air. For example, aluminum or aluminum compound powder is placed in a furnace to heat and stir. Within hours of completion of this method, an oxide layer was formed on the surface of aluminum or an aluminum compound. Therefore, the absorption rod 11 is made of an aluminum compound or an aluminum alloy. Therefore, the light weight has the ability to shield neutrons, and the distance between the used fuel assemblies can be reduced. If τ is used, the same amount of used fuel assembly is used to reduce the weight of the container. Any material with neutron-absorbing properties can be used instead of aluminum compounds or aluminum alloys. Therefore, the fuel rod 4 itself can be used instead of the absorption rod 11. According to the first specific embodiment, since the absorption rod 11 having the ability to absorb neutrons is inserted into the control rod duct 5 and the measurement tube 6 of the used fuel assembly, the space inside the control rod duct 5 and the measurement tube 6 can be effectively absorbed. Neutrons and neutrons emitted from the used fuel assemblies can be reduced, so the distance between subcritical states of used fuel assemblies can be shortened. Alternatively, the use of the absorption rod block 10 and the end plate 12 in combination with a plurality of absorption rods i, and the absorption rods 11 are inserted into the control rod conduit 5 and the measuring tube 6 in a batch manner, leading to an increase in work efficiency. A second specific embodiment is described below. The second specific embodiment is related to a receipt. -15- This paper size is applicable to Chinese National Standard (CNS) A4 (210 X 297 mm) (Please read the precautions on the back before filling this page) Decoration I— I imw · nnnn ϋ I 1_ _ Printed by the Employees 'Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs Printed by the Employees' Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 476072 A7 _B7_____ V. Description of the Invention (13) The container is used to hold the PWR in which the absorber rod of the first embodiment is inserted 1 1. Cancel the cooling water passage on the backboard in the container. Fig. 6 is a radial sectional view of a receiving container, which is an improvement of the conventional receiving container for PWR shown in Fig. 17. The plate 817 shown in FIG. 17 has a high uranium enrichment factor of the fuel assembly used by PWR, a larger amount of uranium fuel per unit fuel assembly than the BWR fuel, and a wider cross-sectional area of the fuel assembly, and a higher The system is reactive, so in order to effectively absorb neutrons to slow them down during the cooling process, the cooling water passage 816 is filled with water as a neutron moderator. The used fuel assembly in which the absorption rod 11 described in the first embodiment contains a neutron-absorbing substance is inserted into the used fuel assembly, thereby reducing neutrons leaking from the used fuel assembly. As a result, the distribution distance of the subcritical state for controlling the cooling using the completed fuel assembly may be shortened, so that the cooling water passage 816 is not required during the cooling process. Therefore, the plate 50 of the basket 4 9 of the container 40 for the PWR shown in FIG. 6 has no cooling water passage as the basket structure of the BWR. For example, the PWR receiving container 40 shown in FIG. 6 has the same volume and volume as the gap 811 of the PWR receiving container 800 shown in FIG. 17. The thickness of the plate 50 can be reduced to accommodate more use. Complete fuel assembly. For example, the home appliance 800 shown in FIG. 17 can hold 19 used fuel assemblies, and the storage container 40 shown in FIG. 6 can hold 32 used fuel assemblies. The use of the container 40 of the second embodiment can hold more than 13 used fuel assemblies. In other words, the degree of integration of the used fuel assembly can be increased. In the same type of basket as shown in Fig. 17, if the first embodiment is used, the paper size of this paper is -16- Chinese National Standard (CMS) A4 (210 X 297 mm) (please read the precautions on the back first) (Fill in this page again)

476072 A7 1 B7 V. Description of the invention (14) After using the fuel assembly, the neutron emission is reduced, and the resin thickness can be reduced. As a result, it is possible to reduce the size of the receiving container for the same number of used fuel assemblies. In the second specific embodiment, the storage chamber 55 is formed in a grid pattern by the joint plate 50. However, the storage chamber may be constituted by a square tube. In addition, if the used fuel assembly of the first embodiment is incorporated, the thickness of the plates constituting the container basket can be reduced to a neutron absorption capacity equivalent to the insertion of the absorber rod of the fuel assembly. The number of used fuel assemblies held in the container can be increased. In addition, there is no need to install a cooling water passage in the plate or square pipe, which is a characteristic of the pwR container, and a plate or square pipe of a simple structure such as a plate or square pipe for BWR can be used. A third specific embodiment is described below. In the first embodiment, a plurality of absorption rods 11 are composed of the absorption rod blocks 10, and the plurality of absorption rods i are inserted in a batch manner to improve work efficiency. In addition, in the third embodiment, it is easier to insert the used fuel assembly of the plurality of absorbing rods 11, which is safe and secure. FIG. 7 shows the configuration of the insertion device according to the second embodiment. This insertion device includes an upper end plate 61 connected to the absorption rod 11, a lower end plate 62 guided the absorption rod 11, and a suspension 64 for moving the upper end plate 61. The upper end plate 6 1 is equivalent to the absorption rod block 10. The upper end plate 6 1 and the lower end plate 62 are suspended by a hanger 6 3. Fig. 8 is a sectional view of the lower end plate 62 along line B-B. The lower end plate 6 2 has a guide hole 77 for guiding the absorption rod 11. The position of the guide hole 77 relative to the control rod conduit 5 and the measuring tube 6. If the upper end plate 6 1 and the lower end plate 6 2 are suspended by a hanger -17- This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 public love) -------- 1 ----- install (please Please read the precautions on the back before filling out this page} ----------- Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 476072

V. Description of the invention (15) (Please read the precautions on the back before filling out this page) 6 3 Suspension 'and keep it still or in the original state, the front end of the absorption rod must be inserted into at least the guide hole 77. The horizontal width of the upper end plate 61 and the lower end plate 62 must be wide enough to allow insertion from the upper opening of the upper nozzle 2, and the width must be at least sufficient to form the guide holes 7 7 of the technical rod duct 5 and the measuring tube 6. A hanging hole 7 8 is located at the center of the upper end plate 61. The inner wall of the suspension hole 78 has a groove 70 for hooking the claw 69 of the above-mentioned clamp 65. The clamp 65 rotates freely along the fulcrum 68 of the upper end plate opposite the flat hanging plate 60. The fulcrum is attached to the upper portion of the clamp 65, and the claw 69 is located at the lower portion of the clamp 65 and tensioned by the tension spring 66. Open to secure the upper end plate 61. If the upper end plate 61 'is not supported, that is, if the upper end plate 61 and the lower end plate 62 are separated from the suspension portion 64, the upper part of the clamp 65 is pressed against the spring by the air cylinder 67 connected to each other. The tension of 66 pushes open the upper part of the clamp 65. As a result, the claws 69 are separated from the groove 70 and separated through the hanging hole 78. The suspension plate 60 and the load sensor 81 are suspended by the sling 84, and the load is sensed. The device "is suspended on a hook 82 by a sling 83 to detect the suspension load, and the hook 82 is connected to a cart, which is not shown in the figure. The crane moves the entire suspension portion 64, in particular, vertical private movement, and simultaneously moves the upper end plate 61 and the lower end plate 6 connected by the clamp 65 at the same time. The consumer cooperative of the Intellectual Property Bureau of the Ministry of Economy is printed on the suspension plate 6 (Γ An optical fiber 71 corresponding to the vertical movement of the lower end plate 62 bypasses the winder 73. The optical fiber 71 passes through the through hole 76 of the hanging plate 60 and the through hole 75 of the upper end plate 61 and extends to the image hole 94 of the lower end plate 62. Optical fiber In front of 71, there is a lens 7 2 of the optical fiber 7 1, and the lens 7 2 directly passes through the image hole 9 4. The front end of the optical fiber 7 1 has a counterweight 9 j, and the lens 7 2 of the optical fiber 7 is pressed, so that The image can be captured stably. The other end of the optical fiber 71 is connected through a winder 73. -18- This paper size applies to China National Standard (CNS) A4 (21 × 297 feet). Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs. V. Description of the invention (16) The developing machine, the image close to the lens 72 is captured by a camera, etc. The hanging plate 60 additionally has a detector 92 including a lower projection. At the lower end plate, there is a detector on the upper side. Test the projection 93, and the detection projection 93 passes through only the through hole of the upper board 6 1 7 4 can be in contact with the lower projection of the detector 92. If the detection projection 93 contacts the lower projection of the detector 92, the absorption rod " is fully inserted into the control rod guide f5 and the measuring tube 6. This This contact is detected by the detector 92, and the detection result is transmitted to an unshown detector. Referring to Figs. 9 to 11, the operation of inserting the absorption rod u by the insertion device will be described. The shape shown in Fig. 7 is the original insertion. In the state, the upper end plate 6 1 is connected to the suspension portion 6 4 and the hanger 6 3 is extended to the full range. In this state, the relative arrangement of the position of the lower end plate 62 and the position of the upper nozzle 2 is detected by the lens 72 of the optical fiber. Therefore, the relative configuration is detected by image processing, and it is determined whether the deviation of the relative configuration is smaller than the specified value. For example, using a graphic pairing, if it is smaller than the specified value, the position of the lower end plate 62 and the upper nozzle 2 are determined to be relative, that is, , The guide hole 77 of the lower end plate 62 is matched with the relative position of the control rod duct 5 of the upper nozzle 2.: More specifically, as shown in FIG. 9A, there is no deviation in the relative position. If the position of the lower end plate 62 deviates from the upper part of the figure On the right, as shown in Figure 9b, the position of the passage 21 and the control rod catheter 5 In the lower right corner of the figure, and the nozzle box 100 on the upper end wall 2 ^ is wider. On the other hand, if the position of the lower end plate 62 is offset to the lower right side of the figure, as shown in FIG. 9C, the passage 2 i The position of the control rod duct 5 is in the upper right corner of the figure, which causes the nozzle box 100 to be smaller. Therefore, the two-position deviation of the lower end plate 62, that is, the position deviation of the absorption rod 11, can be detected by image type pairing, as shown in FIG. 9B and FIG. It is shown in 9C and in the reference image in Figure 9A. This position deviation data is transmitted to the operator to control the crane. According to these positions, the operator applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) based on the paper size.

Please read the note on the back ii,! Page I I I Order 19- 4 ^ 6072 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs A7 B7 V. Description of the invention (17) Operate the crane with poor data to avoid position deviation. • After the position deviation correction is completed, the operator lowers the crane and also lowers the upper end plate 6 1, thereby lowering the absorption rod 11, causing the absorption rod i i to be inserted into the control rod conduit 5 and the measuring tube 6 through the guide hole 7 7. At this time, there is no deviation in the position where the lower end plate 62 is fixed on the inner upper side of the upper nozzle 2. After the absorption rod 11 is inserted into the control rod catheter 5, the lower projection of the detector 92 is in contact with the detection projection 9 3, and the detection result is transmitted to the detector not shown. According to the results of the test, the operator extended the cylinder 67 to release the claws 6 9 from fishing. Then, the operator lifts the crane to disengage the upper end plate 6 j from the suspension portion 64. Whether the disconnection is true or not can be checked by the load sensor 81. As a result, as shown in FIG. 11, the absorption rod is inserted into the control rod duct 5 and others, and the upper end plate 61 supports the absorption rod u and the lower end plate 62 to guide the absorption rod ^ to be placed inside the upper nozzle 2 without exceeding the outside of the upper nozzle 2. type. Therefore, the shape of these used fuel assemblies is the same as the shape of the used fuel assemblies without the absorption rod " inserted therein. : In addition, the contact between the detector 9 2 and the detection protrusion 9 3 can be detected by electromagnetic or electric devices. Conversely, using an optical detector such as the detector 9 2, the distance can be measured with optical instruments, 1 to determine whether the riding is complete If the distance becomes shorter than the specified threshold. The material for manufacturing the upper end plate 61 and the lower end plate 62 has a neutron absorption capacity such as B_ material, which is the same as the absorption rod. If it is a wet container stored in water, it can reduce the thickness of the resin in the direction of the cover. According to the third specific embodiment, 'the relative position deviation of the absorber rod and the control rod catheter 5 and other is measured using the insertion device, and after the position is approximately corrected, the absorber rod and the control rod catheter 5 and other relative positions are matched, and the absorption rod is additionally used (Please read the precautions on the back before filling in this page.) Pack -20- A7 B7 V. Description of the invention (18 Band-shaped such as the end 'absorbent rod can be reliably and easily inserted into the control rod catheter 5. Also inserted by detection The completion of 'can ensure insertion safety. The fourth embodiment is described below. In the second embodiment, the used fuel assembly of the first embodiment is to be stored in a container. However, the' fourth embodiment 'provides Method for storing used fuel assembly in storage tank.

FIG. 12 is a schematic diagram showing a configuration in which a fuel assembly 101 stored as a used fuel assembly is stored in a storage tank 102. As shown in FIG. 12, the fuel assembly 101 is inserted with the absorbing rod j j shown in the first embodiment, and is stored in a storage room of the rack 104 arranged in the storage tank 102, and the tank is filled with water 103. Although the fuel is stored in the pool 102 at a safe distance d, because the absorption rod 11 has a neutron absorption capacity inserted into the fuel assembly 101, the distance d is shorter than the distance d without the absorption rod 11 being inserted. Therefore, according to the fourth specific embodiment, the fuel assembly 101 can be configured at a high density, the number of stored fuel assemblies 101 can be increased, or the size of the storage pool 102 can be reduced. Printed by the Consumers ’Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs. In the first to fourth specific embodiments, the PWR 1 4 X 1 4 is shown using the fuel assembly as an example, but it is not limited to this example. Obviously, other similar The fuel assembly is also suitable, such as the configuration of 1 7 X 1 7 or 1 5 X 1 5 shown in Figure 16. As described herein, according to a feature of the present invention, the absorption rod used has a shape almost the same as the shape of a cylindrical control rod used by a PWR reactor to control the reactivity of the reactor, and has a neutron absorption capacity. The control rod catheter or control rod catheter inserted into the used fuel assembly includes -21 This paper size applies to China National Standard (CNS) A4 (210 X 297 mm)

476072 V. Description of the invention (19) Measuring tube, so neutrons can be effectively shielded in the used fuel assembly. According to another feature of the present invention, the absorber rod is made of a composite material or an aluminum alloy added with a boron or boron compound powder having neutron absorption performance to the aluminum or aluminum alloy powder. Because the absorbent rod is made of this material, it will not be damaged by a slight impact during transportation. If, the neutron absorption capacity can be maintained even during transportation. For example, it is safer and more ideal than an absorption rod structure filled with boron powder in the tube. According to another feature of the present invention, the insertion absorption rod group has a shape almost the same as the shape of the cylindrical control rod used by the PWR reactor to control the reactivity of the reactor, and has a neutron shielding ability, and is inserted into the used fuel assembly. The control rod catheter or control rod catheter group includes a measuring tube, and puts the used fuel assembly into a collection container. The number of neutrons emitted from the used fuel assembly can be reduced, resulting in the used fuel assembly. The distribution distance can be shortened. Therefore, the number of used fuel assemblies contained in the main body cavity can be effectively increased. The periphery of the main body has neutron shielding and factory line shielding, or the main cavity is the same number of containers as the previous technique. The shape can be reduced or the neutron shielding thickness can be reduced, thereby reducing the overall container size. According to the container with another feature of the present invention, if the PWR control rod is recovered, the absorption rod is used as a control rod, and the control rod is kept inserted into the used fuel assembly, so the recovery control rod can be effectively used. In addition, because it is equivalent to inserting: the neutron absorption capacity or the neutron mitigation capacity of the PWR fuel assembly's absorber rod cross-sectional area, the PWR uses the fuel assembly assembly's support plate or square tube. The considerable reduction in thickness' its cross-sectional area is equivalent to inserting the fuel assembly used by PWR-22.- This paper size applies to China National Standard (CNS) A4 specifications (210 X 297 mm) (Please read the precautions on the back— — Write this page) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs 476072 A7 B7 V. Description of the invention (20) The neutron absorption capacity or neutron mitigation capacity of the absorber. In this way, due to the shape of the basket, the water area of the PWR basket has a high uranium enrichment factor, which can be more detailed, which can reduce the south. , And improve basket production efficiency. In addition, 'because the absorption rod and basket are made of aluminum composite material or aluminum alloy with boron or boron compound powder with absorbing neutron properties in eight or eight or eight alloy powders' absorb from the side and surrounding of the used fuel assembly Neutron, because the absorption rod is inserted into the fuel assembly, requires low strength properties, so that weight reduction can be considered. According to the insertion device according to still another feature of the present invention, the relative positions of the through-hole group of the guide plate and the control rod catheter group using the Bizhanhan assembly are adjusted according to the detection result of the position detector, and the group is absorbed. The reduction causes the through-hole group to become a guide hole, and the long absorption rod group can be safely inserted into the control rod catheter or the control rod catheter including the measuring tube, so the absorption rod can be easily and safely inserted into the control rod catheter and other, resulting in the efficiency of the insertion work Can be improved. 'Additionally', the distance detector starts to detect if the distance between the hanger and the fixed part becomes smaller than the stipulation. I fully understand that the absorption rod group can be safely inserted into the control rod ^ 'and prevent the absorption rod from falling during the insertion, so The efficiency of the insertion work can be improved. 'The insertion work can be checked at the end, so that the insertion work can be completed safely. According to the transportation and storage method according to another feature of the present invention, in the insertion step, the insertion absorption rod group has a shape almost the same as the shape of the cylindrical control rod used by the PWR reactor to control the reactivity of the reaction weight, and has a neutron shield. Ability to insert the control rod catheter or control rod of the used fuel assembly -23- This paper size is applicable to the Chinese National Standard (CNS) A4 specification (21 × X 297) ~ (Please read the note on the back first to fill in $ This page) is printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs and printed by 476072 A7 _B7_ V. Description of the invention (21) (Please read the note on the back 3 to complete this page) The catheter group includes measuring tubes and the steps of anti-storage during transportation. The state of transporting and storing the PWR fuel assembly is inserted into the absorption rod group, and the distance between the used fuel assemblies can be shortened. Therefore, when transporting and storing the PWR fuel assembly, the PWR fuel is used. The density of the assembly can be increased, and more efficient transportation and storage can be obtained. In addition, if the control rod for PWR is recovered, the absorption rod is used as the control rod of PWR, and the control rod remains inserted into the used fuel assembly, so the recovery control rod can be effectively used. Although the present invention has been fully and clearly explained according to specific embodiments, the scope of the following attached patent applications can be used as an illustration, but it is not limited to all those skilled in the art can make modifications and changes without departing from the basic guidance described herein. Specific implementation methods for other structures. Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs -24 · This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) ~

Claims (1)

476072 Patent Application No. 89122814 Chinese Patent Application Amendment (December 1990) 6. Scope of patent application 1. An absorption rod, which has almost the same shape as the cylindrical control rod used by the PWR reactor to control the reactivity of the reactor, and has a neutron shielding ability. 2. For example, the absorber rod of item 1. It also includes a fixing member for fixing the absorber rod in a position relative to the control rod conduit of the fuel assembly used by PWR or a control rod including a measuring tube. Sectional position of the catheter. 3. The absorbing rod according to item 1 of the patent application range, wherein the absorbing rod is composed of an aluminum composite material or an aluminum alloy, and these are made by adding boron or a boron compound powder having neutron absorption performance to the aluminum or aluminum alloy powder. production. 4. An absorbing rod for inserting a control rod conduit or a measuring tube of a fuel assembly that has been used, wherein the absorbing rod is composed of an aluminum composite material or an aluminum alloy, and these are made by adding neutron absorption The performance boron or boron compound powder is made of aluminum or aluminum alloy powder. When the used fuel assembly is transported and stored in the container, the absorption rod is used, and the absorption rod is inserted into the control rod conduit or the measuring tube. 5. —Receiving container, including: a group of absorber rods used to insert a control rod conduit or a measuring tube of the fuel assembly used by PWR, having the shape of a cylindrical control rod used in a PWR reactor to control the reactivity of the reactor Almost the same shape, and has neutron shielding ability; PWR uses a complete fuel assembly, which has a control rod catheter, in which the absorption rod group is inserted, or includes a measuring tube one control rod tube group. This paper is suitable for China National Standard (CNS) A4 specification (210 X 297 mm) 476072 A BCD 6. Scope of patent application • A basket, which forms a grid storage room to accommodate the fuel assembly used by PWR, and the absorption rod is inserted into it Group; a main body housed in the basket, with neutron shielding outside to shield T-rays; and a detectable cover placed in the opening of the main body to insert the PWR into the absorption rod group The fuel assembly is put into and taken out of the grid storage chamber. 6. The container of claim 5 in which the absorption rod is a control rod for PWR. 7. For example, the collection container of the scope of application for patent No. 5, wherein the PWR used fuel assembly in the collection container equivalent to the neutron absorption capacity or neutron mitigation capacity of the absorption rod cross section of the fuel assembly used by PWR The considerable thickness of the component plate or square tube of the body support basket is reduced, and its cross-sectional area is equivalent to the neutron absorption capacity or neutron mitigation capacity of the fuel assembly absorber rod inserted into the PWR. 8. The container as claimed in item 5 of the patent application scope, wherein the absorption rod is composed of aluminum composite material or aluminum alloy, and these are made by adding boron or boron compound powder having neutron absorption performance to aluminum or aluminum alloy powder. production. 9. An insertion device comprising: an absorbing rod element having a shape almost the same as the shape of a cylindrical control rod used by the PWR reactor to control the reactivity of the reactor, and located at a position relative to the control rod conduit of the fuel assembly used by PWR Or a cross-section position of a control rod tube including a measuring tube, which can pass the fixing part through PWR -2- This paper size applies to Chinese National Standard (CNS) A4 specification (210 X 297 mm) Α8 Β8 C8 2. The scope of the application for the patent uses the upper nozzle opening of the fuel assembly to be inserted into the upper nozzle, and the fixing rod is used to fix the absorption rod group having the neutron shielding ability; a guide member can be inserted into the upper nozzle through the upper nozzle opening of the fuel assembly that is used by PWR 'Has a through-hole for inserting the absorption rod group into the control rod catheter or a cross-section position including a measuring tube relative to the control rod catheter' causes the front end of the absorption rod group to be inserted into the through-hole and suspended on the fixing member in a stationary state A suspension device for detachably suspending the fixing member of the absorption rod block and moving the absorption rod block vertically during installation; and a position detector located on the fixing member to detect the position of the through-hole group on the guide member and The relative configuration of the control rod catheter position used by the PWR fuel assembly with respect to PWR; the position of the through-hole group and the relative position of the control rod catheter group are adjusted according to the detection result of the child detector, and the absorption rod group is lowered to insert the control rod. The catheter or a control rod catheter including a measuring tube. 10. The insertion device according to item 9 of the scope of patent application, further includes a distance detector to detect whether the distance between the hanger and the fixed part is within a specified value. 1 1 · A method for transporting and storing a used fuel assembly includes-step insertion-the absorption rod has a shape almost the same as that of a cylindrical control rod of a PWR reactor to control the reactivity of the reactor, and has a neutron Shielding ability, insert the fuel used by PWR: basic; rod catheter or-including-measuring rod control rod catheter; and one-step control and one-step transportation and storage of fuel used by PWR Install? · Τ -3- 476072 8 8 8 8 A B c D 、 Scope of patent application This group of absorption rods. 1 2. The method for transporting and storing the used fuel assembly according to item 11 of the patent application scope, wherein the absorption rod is a control rod used by PWR. -4- This paper size is applicable to China National Standard (CNS) A4 (210X297 mm)