Reactor refueling system and refueling methods

Abstract

A refueling system and refueling method for a reactor. The reactor includes a container formed by a stack container and a stack cover, and a core arranged in the container. The refueling system of the reactor includes: an off-stack refueling device, located outside the container, used to move the spent fuel to be replaced in the container from the core to the outside of the stack, or to move the new fuel to be placed outside the container from the outside of the stack to the core; a guide device, which can be rotatably installed on the stack cover around the axis of the stack cover, and the guide device has a refueling channel that passes through the stack cover; wherein the spent fuel to be replaced is moved from the core to the outside of the stack through the refueling channel, or the new fuel to be placed is moved from the outside of the stack to the core through the refueling channel. The spent fuel to be replaced can be moved out of the refueling channel or the new fuel to be placed can be moved into the refueling channel using only the off-stack refueling device. The refueling system has a simple structure, a small number of devices for completing the grabbing action, convenient operation, high reliability, and a smaller radial size of the reactor.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of nuclear reaction technology, and in particular to a reactor fuel replacement system and a fuel replacement method. Background Art

[0002] The percentage of uranium that can be burned is limited because the amount of fissile material will eventually reach a stage where it is insufficient to sustain the chain reaction. In addition, fission products will generate pressure in the fuel cladding due to expansion and deformation of the fuel elements. When the fuel elements reach the required burnup, they must be removed from the pile and replaced with new elements. This process is called reactor refueling. The pool-type reactors currently in use in my country include experimental fast reactors and swimming pool-type light water research reactors. The experimental fast reactor uses an in-pile refueling machine, a hoist structure and an out-of-pile transporter to achieve the replacement of new and spent components.

[0003] However, the structures of the in-pile material changer, elevator structure and out-of-pile transfer machine are complex, the process is cumbersome, and the axial and radial space requirements of the reactor are large. Summary of the invention

[0004] Embodiments of the present invention provide a reactor fuel replacement system and a fuel replacement method.

[0005] A refueling system for a reactor according to an embodiment of the present invention, the reactor includes a container formed by a stack container and a stack top cover, and a core arranged in the container, the refueling system for the reactor includes: an off-stack refueling device, located outside the container, used to move spent fuel to be replaced in the container from the core to the outside of the stack, or to move new fuel to be placed outside the container from the outside of the stack to the core; a guide device, which is rotatably mounted on the stack top cover around the axis of the stack top cover, the guide device having a refueling channel that passes through the stack top cover; wherein the spent fuel to be replaced is moved from the core to the outside of the stack through the refueling channel, or the new fuel to be placed is moved from the outside of the stack to the core through the refueling channel.

[0006] A method for refueling a reactor according to an embodiment of the present invention comprises: controlling new fuel to be placed in a containing chamber of an off-core refueling device; controlling a grabbing assembly to grab spent fuel to be replaced and move the spent fuel to be replaced from a core to the containing chamber; controlling a grabbing assembly to grab new fuel to be placed and move the new fuel to be placed from the containing chamber to the core.

[0007] In the refueling system of the reactor in the embodiment of the present invention, the spent fuel to be replaced can be moved out of the refueling channel or the new fuel to be placed can be moved into the refueling channel by only using the off-core refueling device, and the spent fuel to be replaced does not need to be turned over in the container. A large number of special equipment such as the in-pool turning machine, refueling machine and hoist, component transfer barrel, nuclear fuel transfer pool, etc. can be omitted. The refueling system has a simple structure, a small number of devices for completing the grabbing action, convenient operation, high reliability, and a smaller radial size of the reactor.

[0008] Additional aspects and advantages of the embodiments of the present invention will be given in part in the following description, and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0010] Figure 1 It is a structural schematic diagram of the reactor refueling system according to the embodiment of the present invention when the reactor is not refueled.

[0011] Figure 2 yes Figure 1 A top view of the reactor with the guide device of the reactor refueling system located in the reactor.

[0012] Figure 3 It is a structural schematic diagram of a reactor refueling system according to an embodiment of the present invention for refueling a reactor.

[0013] Description of main component symbols:

[0014] 10. Material changing system;

[0015] 100, off-pile material exchange device; 110, material exchange body; 111, accommodating chamber; 120, grabbing assembly;

[0016] 200, guide device; 210, material changing channel;

[0017] 300. Switchgear;

[0018] 400, air extraction device; 500, air filling device; 600, first rotating body; 700, second rotating body; 800, transportation device for spent fuel to be replaced; 900, transportation device for new fuel to be placed;

[0019] 20. Reactor; 21. Reactor vessel; 22. Reactor top cover; 23. Container; 24. Reactor core. DETAILED DESCRIPTION

[0020] The embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0021] Figure 1 20 is a schematic structural diagram of the reactor 20 refueling system 10 according to the embodiment of the present invention when the reactor 20 is not refueled. Figure 1The reactor 20 includes a container 23 formed by a reactor container 21 and a reactor top cover 22, and a reactor core 24 disposed in the container 23. The refueling system 10 of the reactor 20 includes an off-core refueling device 100 and a guide device 200.

[0022] The off-core refueling device 100 is located outside the container 23, and is used to move the spent fuel to be replaced in the container 23 from the core 24 to the outside of the core, or to move the new fuel to be placed outside the container 23 from the outside of the core to the core 24. The guide device 200 is rotatably mounted on the top cover 22 around the axis of the top cover 22, and the guide device 200 has a refueling channel 210 that passes through the top cover 22. The spent fuel to be replaced is moved from the core 24 to the outside of the core through the refueling channel 210, or the new fuel to be placed is moved from the outside of the core to the core 24 through the refueling channel 210.

[0023] The present embodiment is described below using a pool-type lead-bismuth reactor 20, but is not limited thereto.

[0024] Further, the reactor 20 includes a container 23 formed by a stack container 21 and a stack cover 22, and a core 24 disposed in the container 23. The container 23 of the pool-type lead-bismuth reactor 20 is a pool body boundary of a primary lead-bismuth medium, the stack cover 22 is located above the stack container 21, and the core 24 of the reactor 20 is located in the middle and lower part of the container 23.

[0025] Furthermore, the off-core refueling device 100 is located outside the container 23. This means that when the reactor 20 is not refueling, the off-core refueling device 100 is located outside the container 23. The off-core refueling device 100 is used to move the spent fuel to be replaced in the container 23 from the core 24 to the outside of the reactor, or to move the new fuel to be placed outside the container 23 from the outside of the reactor to the core 24. In other words, the off-core refueling device 100 can simultaneously realize loading and unloading, has a simple process flow, uses fewer devices, and is convenient for staff to operate.

[0026] Specifically, the spent fuel to be replaced is a fuel assembly located in the core 24 that needs to be replaced and has been used. The new fuel to be placed is a new fuel assembly that has not been used.

[0027] Furthermore, the guide device 200 can rotate around the axis of the reactor top cover 22, that is, the guide device 200 and the reactor top cover 22 move relative to each other, and the guide device 200 can rotate by itself or with other structures. The guide device 200 is rotatably mounted on the reactor top cover 22, so that the out-of-core refueling device 100 can replace the spent fuel to be replaced at different positions of the core 24.

[0028] Furthermore, the material replacement channel 210 is arranged through the stack top cover 22, that is, both the spent fuel to be replaced and the new fuel to be placed are moved to the outside of the stack through the stack top cover 22.

[0029] The refueling system 10 of the present embodiment can move the spent fuel to be replaced out of the refueling channel 210 or move the new fuel to be placed into the refueling channel 210 by only using the off-core refueling device 100. There is no need to turn the spent fuel to be replaced in the container 23, and a large number of special equipment such as the in-pool turning machine, refueling machine and hoist, component transfer barrel, nuclear fuel transfer pool, etc. can be omitted. The refueling system 10 has a simple structure, a small number of devices for completing the grabbing action, convenient operation, high reliability, and a smaller radial size of the reactor 20.

[0030] Figure 3 2 is a schematic structural diagram of a reactor 20 refueling system 10 according to an embodiment of the present invention for refueling a reactor 20. Figure 1 and Figure 3 The material changing system 10 also includes a switching device 300 .

[0031] The switch device 300 is connected to the guide device 200 , and the switch device 300 is configured to have a refueling state capable of opening the refueling passage 210 and a sealing state capable of closing the refueling passage 210 .

[0032] Furthermore, the switch device 300 and the guide device 200 may be fixedly connected, for example, by welding or fasteners, to enhance stability and sealing during material exchange. The switch device 300 and the guide device 200 may be detachably connected, which facilitates replacement of the switch device 300 and prolongs the service life of the material exchange system 10.

[0033] Furthermore, when the switch device 300 is in the refueling state, the off-core refueling device 100 can move the spent fuel to be replaced to the outside of the core through the refueling channel 210 , or move the new fuel to be placed to the core 24 through the refueling channel 210 .

[0034] Furthermore, when the switch device 300 is in a sealed state, the refueling channel 210 is closed and sealed. At this time, neither the spent fuel to be replaced nor the new fuel to be placed can enter or exit the core 24 through the refueling channel 210, so as to ensure the sealing of the container 23 and prevent harmful gases from overflowing from the core to the external environment.

[0035] Furthermore, the switch device 300 can be configured as an airlock, or other sealing components, which can be used to seal the material exchange channel 210 .

[0036] See also Figure 1 and Figure 3 The off-pillar material replacement device 100 includes a grabbing assembly 120 .

[0037] The grab assembly 120 is used to grab the spent fuel to be replaced or the new fuel to be placed. When the switch device 300 is in the refueling state, the grab assembly 120 can be moved into or out of the container 23 through the refueling channel 210.

[0038] Furthermore, the grasping assembly 120 includes a claw for grasping to ensure the reliability of grasping.

[0039] Furthermore, the grabbing assembly 120 can grab the spent fuel to be replaced from the core 24 through the refueling channel 210 to the outside of the reactor, and can also grab the new fuel to be placed from the outside of the reactor through the refueling channel 210 to the core 24.

[0040] See also Figure 1 and Figure 3 The off-pillar material exchange device 100 further includes a material exchange body 110 . The grab assembly 120 is movably connected to the material exchange body 110 .

[0041] Furthermore, the grab assembly 120 can move along the axial direction of the material exchange passage 210 to facilitate entering and exiting the container 23. The off-stack material exchange device 100 further includes a driving structure for driving the grab assembly 120 to move.

[0042] Furthermore, the grab assembly 120 includes a connecting rod movably connected to the refueling body 110 and a claw fixedly connected to the connecting rod. The claw can be moved by using the connecting rod to facilitate the movement of the spent fuel to be replaced or the new fuel to be placed.

[0043] In some embodiments, the grab assembly 120 is rotatably connected to the refueling body 110. If the refueling channel 210 is a cylindrical channel, the grab assembly 120 can rotate around the axis of the refueling channel 210; if the refueling channel 210 is a non-cylindrical channel, the grab assembly 120 can rotate around any predetermined axis, so as to accurately grab the spent fuel to be replaced.

[0044] Furthermore, the grabbing assembly 120 includes a connecting rod rotatably connected to the refueling body 110 and a claw fixedly connected to the connecting rod. The claw can be rotated by using the connecting rod to facilitate accurate grabbing of the spent fuel to be replaced.

[0045] See also Figure 3 The refueling body 110 is provided with a containing cavity 111, and the grabbing assembly 120 can move in the containing cavity 111 with the spent fuel to be replaced or the new fuel to be placed.

[0046] Furthermore, when the switch device 300 is in a sealed state, the grab assembly 120 can be located in the accommodating chamber 111 for easy storage. Therefore, the grab assembly 120 can grab the spent fuel to be replaced from the core 24 and move it to a designated position outside the core through the accommodating chamber 111; it can also grab the new fuel to be placed from outside the core and temporarily place it in the accommodating chamber 111, or move it to the core 24 through the accommodating chamber 111.

[0047] Furthermore, the length of the accommodating cavity 111 in the first direction is greater than or equal to twice the length of the spent fuel to be replaced in the first direction, so as to move the spent fuel to be replaced.

[0048] In some embodiments, the length of the spent fuel to be replaced is consistent with the length of the new fuel to be placed in the first direction, that is, the length of the accommodating cavity 111 in the first direction is greater than or equal to twice the length of the new fuel to be placed in the first direction, so as to move the new fuel to be placed.

[0049] In some embodiments, the refueling body 110 is provided with a refueling opening. When the switch device 300 is in the refueling state, the accommodating chamber 111 is connected to the refueling channel 210 through the refueling opening. The grab assembly 120 passes through the refueling opening and enters the refueling channel 210. The inherent physical and chemical properties of the lead-bismuth medium in the lead-bismuth coolant reactor 20 will release highly toxic gases during the normal operation of the reactor 20. 210 Po, therefore, the sealing requirements for the reactor 20 during normal operation or shutdown for refueling are particularly stringent. The accommodating chamber 111 is connected to the refueling channel 210 through the refueling opening, which not only ensures that the off-core refueling device 100 can realize the grabbing and replacement of all fuel assemblies in the core 24, but also ensures the sealing of the radioactive containment boundary of the reactor 20 during the refueling process.

[0050] See also Figure 3 The refueling system 10 further includes an exhaust device 400. The exhaust device 400 is used to extract the gas in the accommodation chamber 111 until the accommodation chamber 111 is in a vacuum. The accommodation chamber is filled with air before the accommodation, but neither the spent fuel to be replaced nor the new fuel to be placed can be in the air, so it is necessary to evacuate the accommodation chamber before the accommodation.

[0051] See also Figure 3 The material exchange system 10 further includes a gas filling device 500. The gas filling device 500 is used to fill the containing chamber 111 with an inert gas, such as argon gas.

[0052] In some embodiments, the guide device 200 has a first opening and a second opening connected to the material exchange channel 210, the material exchange channel 210 is connected to the container 23 through the second opening, and the switch device 300 is used to open or close the first opening.

[0053] Furthermore, the guide device 200 includes a first opening, a second opening and a material changing passage 210, and the material changing passage 210 is connected to the first opening and the second opening. The off-stack material changing device 100 can sequentially move into the container 23 through the first opening, the material changing passage 210 and the second opening, and can also sequentially move out of the container 23 through the second opening, the material changing passage 210 and the first opening.

[0054] Figure 32 is a schematic structural diagram of a reactor 20 refueling system 10 according to an embodiment of the present invention for refueling a reactor 20. Figure 3 The material changing system 10 further includes a first rotating body 600 and a second rotating body 700 .

[0055] The first rotating body 600 is rotatably mounted on the stack top cover 22 and is arranged concentrically with the stack top cover 22. The second rotating body 700 is rotatably mounted on the first rotating body 600 and is arranged eccentrically with the first rotating body 600. The three-rotation design of the first rotating body 600, the second rotating body 700 and the grabbing assembly 120 can realize accurate grabbing of all spent fuels to be replaced.

[0056] Furthermore, the first rotating body 600 can rotate around its axis, and since the axis of the first rotating body 600 is concentric with the stack top cover 22, the first rotating body 600 rotates around the axis of the stack top cover 22. The second rotating body 700 can rotate around the first axis, and the first axis is not colinear with the axis of the stack top cover 22.

[0057] In some embodiments, the guide device 200 is mounted on the second rotating body 700, and the guide device 200 is arranged concentrically with the second rotating body 700. Under the premise of ensuring that the radioactive harmful gas of the reactor 20 does not leak, the space occupied by the container 23 is greatly reduced, the cost is reduced, and the economy is improved.

[0058] Furthermore, the guide device 200 is fixedly connected to the second rotating body 700. During the refueling process of the reactor 20, any system and equipment in the reactor 20 does not need to be disassembled or moved, and the refueling of the reactor 20 can be achieved.

[0059] In some embodiments, the central holes of the stack top cover 22 and the core 24 are reserved with target passages, and the central holes of the stack top cover 22 and the core 24 are both colinear with their axis lines.

[0060] When the switch device 300 is in a sealed state, the reactor 20 is not refueled. At this time, the target channel and the refueling channel 210 on the stack top cover 22 are both in a sealed state to prevent the fission gas in the reactor 20 from leaking to the external environment.

[0061] When the switch device 300 is in the refueling state, the reactor 20 needs to be refueled. At this time, the target is taken out from the core 24 of the reactor 20, the reactor 20 is shut down, and the sealing of the target channel is still ensured.

[0062] The refueling method of the reactor 20 may include steps 1 to 3.

[0063] Step 1: Control the new fuel to be placed in the accommodating chamber 111 of the off-pillar refueling device 100 .

[0064] Step 2: Control the grabbing assembly 120 to grab the spent fuel to be replaced, and move the spent fuel to be replaced of the off-core refueling device 100 from the core 24 to the accommodating chamber 111 of the off-core refueling device 100 .

[0065] Step 3: Control the grabbing assembly 120 to grab the new fuel to be placed, and move the new fuel to be placed in the off-core refueling device 100 from the accommodating cavity 111 to the core 24 .

[0066] Only a single spent fuel to be replaced is replaced each time, and steps 1 to 3 are repeated until all the spent fuel to be replaced in the core 24 is replaced.

[0067] In some embodiments, step 1 includes step 1.1 and step 1.2.

[0068] Step 1.1: Control the new fuel transportation device 900 to place the new fuel into the accommodating chamber 111 of the off-pillar refueling device 100 .

[0069] Step 1.1: Control the off-piles material exchange device 100 to move above the guide device 200 .

[0070] In some embodiments, step 2 includes steps 2.1 to 2.6.

[0071] Step 2.1: Control the external material exchange device 100 to connect with the switch device 300.

[0072] Step 2.2: Control the vacuum device 400 to perform vacuum processing on the accommodating chamber 111 of the out-of-pile material exchange device 100 .

[0073] Step 2.3: Control the charging device 500 to fill the accommodating chamber 111 of the out-of-pile material exchange device 100 with inert gas.

[0074] Step 2.4: Control the switch device 300 to be in a material changing state to connect the accommodating cavity 111 of the external material changing device 100 and the material changing channel 210 of the guide device 200 of the external material changing device 100.

[0075] Step 2.5: Control the first rotating body 600 and the second rotating body 700 to rotate, so as to move the guide device 200 of the out-of-core material replacement device 100 to the position where the spent fuel is to be replaced.

[0076] Step 2.6: Control the grabbing assembly 120 to grab the spent fuel to be replaced in the external refueling device 100 and move it to the accommodating chamber 111 of the external refueling device 100.

[0077] In some embodiments, step 3 includes steps 3.1 to 3.4.

[0078] Step 3.1: Control the grabbing assembly 120 to place the new fuel of the external refueling device 100 located in the accommodating cavity 111 of the external refueling device 100 into the core 24 of the external refueling device 100.

[0079] Step 3.2: Control the switch device 300 of the external material exchange device 100 to be in a sealed state of the external material exchange device 100.

[0080] Step 3.3: Control the exhaust device 400 of the external material exchange device 100 to perform vacuum processing on the accommodating chamber 111 of the external material exchange device 100.

[0081] Step 3.4: Control the spent fuel transportation device 800 to move the new fuel to be placed in the external refueling device 100 out of the external refueling device 100.

[0082] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0083] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0084] In the description of the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0085] The disclosure below provides many different embodiments or examples to realize different structures of the present invention. In order to simplify the disclosure of the present invention, the parts and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present invention. In addition, the present invention can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplicity and clarity, which itself does not indicate the relationship between the various embodiments and / or settings discussed. In addition, the present invention provides various specific examples of processes and materials, but those of ordinary skill in the art can be aware of the application of other processes and / or the use of other materials.

[0086] In the description of this specification, the description with reference to the terms "one embodiment", "certain embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0087] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A refueling system for a reactor, the reactor comprising a container formed by a reactor container and a reactor top cover and a reactor core arranged in the container, characterized in that: The material changing system comprises: An off-core fuel replacement device, located outside the container, is used to move the spent fuel to be replaced in the container from the core to the outside of the core, or to move the new fuel to be placed outside the container from the outside of the core to the core; A guide device is mounted on the pile top cover so as to be rotatable around the axis of the pile top cover, and the guide device has a material replacement channel penetrating the pile top cover; The spent fuel to be replaced is moved from the core to the outside of the reactor through the refueling channel, or the new fuel to be placed is moved from the outside of the reactor to the core through the refueling channel; The material changing system also includes: A first rotating body, rotatably mounted on the stack top cover and arranged concentrically with the stack top cover; A second rotating body, rotatably mounted on the first rotating body and eccentrically disposed with respect to the first rotating body; The guide device is installed on the second rotating body, and the guide device is arranged concentrically with the second rotating body; The material changing system also includes: A switch device connected to the guide device, wherein the switch device is configured to have a material changing state capable of opening the material changing channel and a sealing state capable of closing the material changing channel; The off-pile material replacement device comprises: A grabbing assembly, used for grabbing the spent fuel to be replaced or the new fuel to be placed; Wherein, when the switch device is in the material changing state, the grabbing assembly can be moved into or out of the container through the material changing channel; The off-pile material replacement device also includes: A refueling body, wherein the refueling body is provided with a containing cavity, and the grabbing assembly can move in the containing cavity with the spent fuel to be replaced or the new fuel to be placed; The length of the accommodating cavity in the first direction is greater than or equal to twice the length of the spent fuel to be replaced in the first direction, so as to move the spent fuel to be replaced; Wherein, the first direction is parallel to the axis of the stack top cover.

2. The material changing system according to claim 1, characterized in that: The grabbing assembly is movably connected to the material changing body.

3. The material changing system according to claim 1, characterized in that: The grabbing assembly is rotatably connected to the material changing body.

4. The material changing system according to claim 1, characterized in that: The material changing body is provided with a material changing opening. When the switch device is in the material changing state, the accommodating cavity is connected with the material changing channel through the material changing opening.

5. The material changing system according to claim 1, characterized in that: The material changing system also includes: The vacuum device is used to extract the gas in the accommodating chamber until the accommodating chamber is in a vacuum.

6. The material changing system according to claim 1, characterized in that: The material changing system also includes: The gas filling device is used to fill the containing cavity with inert gas.

7. The material changing system according to claim 1, characterized in that: The guide device has a first opening and a second opening connected to the material exchange channel, the material exchange channel is connected to the container through the second opening, and the switch device is used to open or close the first opening.

8. The material changing system according to claim 1, characterized in that: The switch device is configured as an airlock.

9. A method for refueling a reactor, characterized in that: include: Control the placement of new fuel to be placed in the accommodating chamber of the off-pillar refueling device; Controlling the grabbing assembly to grab the spent fuel to be replaced, and moving the spent fuel to be replaced from the core to the containing cavity; Controlling the grabbing assembly to grab the new fuel to be placed, and moving the new fuel to be placed from the containing cavity to the core; The control grabbing assembly grabs the spent fuel to be replaced and moves the spent fuel to be replaced from the core to the accommodation chamber, including: Controlling the docking of the off-pile material replacement device with the switch device; Controlling the vacuum device to perform vacuum processing on the accommodating chamber of the off-pillar material exchange device; Controlling the charging device to fill the containing cavity of the out-of-piler material exchange device with inert gas; Controlling the switch device to be in a material changing state to connect the accommodating chamber of the out-of-piles material changing device and the material changing channel of the guide device; Controlling the first rotating body and the second rotating body to rotate so as to move the guide device to the position where the spent fuel is to be replaced; Controlling the grabbing assembly to grab the spent fuel to be replaced and move it to the accommodating chamber of the off-pillar refueling device; The length of the accommodating cavity in the first direction is greater than or equal to twice the length of the spent fuel to be replaced in the first direction, so as to move the spent fuel to be replaced; Wherein, the first direction is parallel to the axis of the stack top cover.

10. The method according to claim 9, characterized in that The method of controlling the new fuel to be placed in the accommodating chamber of the off-pillar refueling device includes: Controlling the new fuel transportation device to place the new fuel to be placed into the accommodating chamber of the off-pillar refueling device; The off-pile material replacement device is controlled to move above the guide device.

11. The method according to claim 9, characterized in that The control grabbing assembly grabs the new fuel to be placed, and moves the new fuel to be placed from the accommodation cavity to the core, including: Controlling the grabbing assembly to place the new fuel to be placed in the accommodating cavity in the core; The control switch device is in a sealed state; Controlling the vacuum device to perform vacuum processing on the accommodating chamber of the off-pillar material exchange device; The spent fuel transport device to be replaced is controlled to move the new fuel to be placed out of the off-pillar material replacement device.

Images