Shielding device for a reactor

Abstract

The present application relates to the field of nuclear reactor equipment, and specifically provides a shielding device for a reactor, aiming at solving the problem of radioactive gas leakage existing in the out-of-pile dry method refueling. For this purpose, the shielding device for the reactor of the present application comprises a multilayer shielding sealed box, a sealed penetration sleeve and an adsorption filtering device. A sealed door is arranged on the upper end face of the multilayer shielding sealed box and the layer plate of each layer, and the lower end face is provided with an opening and is sealingly connected with the top end flange, and each layer is communicated with the adsorption filtering device through a sealed penetration sleeve. The adsorption filtering device is fixed on the multilayer shielding sealed box, and when opened, the gas in each layer of the multilayer shielding sealed box can be extracted and filtered. The device can provide effective shielding and sealing during the process of out-of-pile dry method refueling and the like, avoid the leakage of radioactive gas products while shielding radioactive rays, and effectively reduce the risk of plant radioactive contamination, can meet the requirements of complex environment, and effectively improve the safety.

Description

Technical Field

[0001] This invention relates to the field of nuclear reactor equipment, and more specifically to a shielding device for a reactor. Background Technology

[0002] Throughout the reactor's lifespan, in order to ensure the safe, reliable, and efficient operation of the reactor, refueling, maintenance, and other operations are required.

[0003] In existing technologies, there are two main types of refueling methods: external refueling and internal refueling. Water-cooled reactors use external refueling, where the refueling equipment itself lacks shielding capabilities. Large water pools are used for shielding during operation, making it an external wet refueling method. This requires consideration of the underwater environment and involves numerous supporting equipment. Reactors using liquid metal as a coolant use internal refueling due to the physical properties of the cooling medium. Internal refueling is more structurally complex than external refueling. Although some literature proposes external dry refueling, its sealing effect is limited by its structure, and the risk of radioactive gas leakage still exists.

[0004] Accordingly, a new technical solution is needed in this field to solve the above problems. Summary of the Invention

[0005] The present invention aims to solve the above-mentioned technical problems, namely, to solve the problem that the existing dry refueling method outside the stack has limited sealing effect and poses a risk of radioactive gas leakage.

[0006] To address the aforementioned problems in the prior art, the present invention provides a shielding device for a reactor, comprising a multi-layer shielded sealed housing, a sealing through-sleeve, and an adsorption filtration device. A sealing door is provided on the upper end face and on each layer of the multi-layer shielded sealed housing, and an opening is provided on the lower end face of the multi-layer shielded sealed housing. The opening is capable of sealingly connecting to the top flange of the reactor vessel. Each layer of the multi-layer shielded sealed housing is connected to the adsorption filtration device through a sealing through-sleeve. The adsorption filtration device is fixed to the multi-layer shielded sealed housing and is configured to extract and filter gas from each layer of the multi-layer shielded sealed housing through the sealing through-sleeve when opened.

[0007] By employing the above technical solution, this invention provides effective shielding and sealing during off-site dry refueling and / or maintenance. While shielding against radioactive radiation, the adsorption filtration device absorbs radioactive gases released during top cover disassembly and / or refueling, preventing leakage of radioactive gas products and effectively reducing the risk of radioactive contamination of the plant. Furthermore, the shielding device is layered, with each layer effectively separated, meeting the complex environmental requirements of the refueling and / or maintenance process while effectively improving the safety of the process.

[0008] In the specific embodiment of the shielding device for the reactor described above, the adsorption filtration device includes an exhaust pipe, a vacuum pump, and a gas product filter. One end of each exhaust pipe is connected to a sealed through sleeve, and the other end of each exhaust pipe is connected to the inlet of the gas product filter. The outlet of the gas product filter is connected to the suction port of the vacuum pump, and the exhaust port of the vacuum pump is in communication with the environment.

[0009] By adopting the above technical solution, the present invention can absorb the radioactive gas released during material replacement and / or maintenance, increasing the safety of the operation process, and the gas is discharged after being treated by the adsorption and filtration device, avoiding environmental pollution.

[0010] In the specific embodiment of the shielding device for the reactor described above, the adsorption filtration device is further provided with multiple valves, one of which is provided on each of the external discharge pipelines.

[0011] When the above technical solution is adopted, valves corresponding to one or more layers of the multi-layer sealed shielded box can be opened as needed for adsorption filtration, thereby improving processing efficiency and saving resources.

[0012] In the specific embodiments of the shielding device for the reactor described above, an external overhead crane is also included, which is connected to the multi-layer shielding and sealing housing.

[0013] With the above technical solution, material replacement and / or maintenance processes can be easily carried out.

[0014] In the specific implementation of the shielding device for the reactor described above, an internal gantry crane and a refueling and maintenance mechanism are also included. The internal gantry crane and the external gantry crane can move relative to each other in the horizontal direction, and the internal gantry crane is connected to the refueling and maintenance mechanism.

[0015] When the above technical solution is adopted, the gantry crane consists of an external gantry crane and an internal gantry crane. The two sets of gantry cranes can facilitate the relative movement of the multi-layer shielded sealed box and the material replacement and maintenance mechanism in vertical and horizontal space, and facilitate the removal of the top cover of the stacking container, etc., making the material replacement and maintenance process more convenient.

[0016] In the specific embodiment of the above-mentioned shielding device for reactors, the refueling and maintenance mechanism includes a drive mechanism, a telescopic mechanism, and a disassembly and assembly tool. One end of the drive mechanism is connected to the internal overhead crane, and the telescopic mechanism is connected to the other end of the drive mechanism. The disassembly and assembly tool is located at the bottom of the telescopic mechanism, and a sealing member is provided on the telescopic mechanism. The sealing member can be sealed to the sealing door on the upper surface of the multi-layer shielding sealing box.

[0017] When the above technical solution is adopted, the telescopic mechanism can be retracted when the refueling and maintenance mechanism is lifted away, saving the operating space of the overhead crane. At the same time, the telescopic mechanism can be sealed to the upper end of the multi-layer shielded sealed box, further reducing the risk of leakage of radioactive gas and radioactive radiation.

[0018] In the specific embodiment of the shielding device for the reactor described above, the telescopic mechanism includes a large sleeve and a lower sleeve. The large sleeve is connected to the driving mechanism, and the lower sleeve is telescopically disposed in the large sleeve. The disassembly and assembly tool is disposed at the bottom of the lower sleeve, and the sealing member is disposed on the outer surface of the large sleeve.

[0019] In the specific embodiment of the shielding device for the reactor described above, the sealing door is a double door, which is arranged opposite to each other and each has a notch on its opening side. The two notches form a through hole that allows the telescopic mechanism to pass through.

[0020] By adopting the above technical solution, the operating space for opening the door can be saved, thereby making the entire shielding device more compact.

[0021] In the specific embodiment of the shielding device for the reactor described above, the multi-layer shielding sealing box achieves a sealed connection with the top flange of the reactor vessel by pressing a sealing ring onto the top flange of the reactor vessel.

[0022] By adopting the above technical solution, the sealing effect of the shielding device can be further improved, preventing the leakage of radioactive gases and / or radioactive rays from the connection between the sealed box and the stack container.

[0023] In the specific embodiment of the shielding device for the reactor described above, the size of the sealing door is larger than the size of the reactor vessel top cover.

[0024] The above technical solution facilitates the installation and disassembly of the top cover of the stack container.

[0025] In the specific embodiment of the shielding device for the reactor described above, the size of the opening on the lower end face of the multi-layer shielded sealing box is larger than the size of the top cover of the reactor vessel.

[0026] With the above technical solution, the reactor vessel top cover can be removed from the shielded sealed box, which facilitates the disassembly and maintenance of the top cover and the equipment on the top cover. Moreover, it can effectively shield and isolate the reactor from the external environment during the disassembly and maintenance process.

[0027] In the specific embodiments of the shielding device for reactors described above, the multi-layer shielding sealing box and each layer of the shielding box include a first steel plate layer, a lead shielding layer, and a second steel plate layer.

[0028] By adopting the above technical solution, a good shielding and sealing effect can be achieved. Attached Figure Description

[0029] Figure 1 This is a structural diagram of a shielding device for a reactor provided in one embodiment of the present invention.

[0030] Figure 2 This is a structural diagram of an adsorption filtration device provided in one embodiment of the present invention.

[0031] Figure 3 This is a schematic diagram of a sealing connection between a shielding device for a reactor and the top flange of the reactor vessel, provided in an embodiment of the present invention.

[0032] Figure 4 This is a structural diagram of the sealing cooperation between the material replacement and maintenance mechanism and the sealing door provided in one embodiment of the present invention.

[0033] Figure 5a This is a schematic diagram of a reactor shielding device provided in an embodiment of the present invention during operation, showing the state in which the lower double-opening sealing door is open and the lower sleeve with top cover enters the upper sealed shielding box.

[0034] Figure 5b This is another schematic diagram of a reactor shielding device provided in an embodiment of the present invention during operation, showing the state in which the lower double-opening sealing door is closed, the upper double-opening sealing door is open, and the top cover of the sling is lifted out of the sealed box.

[0035] List of reference numerals

[0036] 1. Multi-layer shielded sealed enclosure, 1-1, first steel plate layer, 1-2, lead shielding layer, 1-3, second steel plate layer;

[0037] 2. Sealed door, 2-1. Upper double-leaf sealed door, 2-2. Lower double-leaf sealed door;

[0038] 3. Sealing through sleeve;

[0039] 4. Adsorption filtration device; 4-1. External discharge pipe; 4-2. Valves; 4-2-1. Upper control valve; 4-2-2. Lower control valve; 4-3. Gas product filter; 4-4. Vacuum pump.

[0040] 5. External hoisting;

[0041] 6. Internal overhead crane;

[0042] 7. Material replacement and maintenance mechanism; 7-1. Drive mechanism; 7-2. Telescopic mechanism; 7-2-1. Large sleeve; 7-2-2. Lower sleeve; 7-3. Disassembly and assembly tools; 7-4. Sealing components.

[0043] 8. Top cover of the stacking container;

[0044] 9. Top flange; 9-1. Sealing ring; 9-1-1. Inner ring sealing ring; 9-1-2. Outer ring sealing ring. Detailed Implementation

[0045] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the invention and are not intended to limit the scope of protection of the invention. Those skilled in the art can make adjustments as needed to adapt to specific applications. For example, although the specification describes it in conjunction with a double-layer sealed enclosure, the present invention can obviously employ other numbers of sealed enclosures as needed; for example, a single-layer sealed enclosure, a triple-layer sealed enclosure, etc., can also be used.

[0046] It should be noted that in the description of this invention, terms such as "upper," "lower," "middle," "one end," "the other end," "top," "bottom," "surface," "end face," "inner," "outer," and "side," which indicate direction or positional relationships, are based on the direction or positional relationships shown in the accompanying drawings. These are used merely for ease of description and do not indicate or imply that the relevant device or element must have a specific orientation, or be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on this invention. Furthermore, ordinal numbers such as "first," "second," "one fan," and "two fans," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0047] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "communication," "replacement," and "maintenance" should be interpreted broadly. For example, a connection can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or other types of connection; it can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0048] Furthermore, those skilled in the art can combine and integrate the different embodiments or examples described herein, as well as the features of the different embodiments or examples, without contradiction.

[0049] To address the problems raised in the background art, the present invention provides a shielding device for a reactor, comprising a multi-layer shielded sealed housing 1, a sealing through-sleeve 3, and an adsorption filter 4, the adsorption filter 4 being fixed to the multi-layer shielded sealed housing 1. A sealing door 2 is provided on the upper end face and on each layer plate of the multi-layer shielded sealed housing 1, and the opening on the lower end face of the multi-layer shielded sealed housing 1 can be sealed to the top flange 9 of the reactor vessel. Furthermore, each layer of the multi-layer shielded sealed housing 1 is connected to the adsorption filter 4 through a sealing through-sleeve 3. When the adsorption filter 4 is opened, gas in each layer of the multi-layer shielded sealed housing 1 can be extracted and filtered through the sealing through-sleeve 3.

[0050] In this way, effective shielding and sealing can be provided during off-site dry refueling and / or maintenance. While the multi-layered shielded sealed enclosure 1 shields against radioactive radiation, the adsorption and filtration device 4 can absorb radioactive gases released during the disassembly and / or refueling of the reactor vessel top cover 8, preventing leakage of radioactive gas products and effectively reducing the risk of radioactive contamination of the plant. Moreover, the shielding device adopts a layered arrangement, with each layer effectively separated, meeting the complex environmental requirements of the refueling and / or maintenance process, while effectively improving the safety of the refueling and / or maintenance process.

[0051] Below, we will combine Figures 1-4 The present invention will now be described.

[0052] like Figure 1 and Figure 2 As exemplified, in one embodiment of the present invention, a shielding device for a reactor includes a multi-layer shielded sealed housing 1, a sealing through-sleeve 3, and an adsorption filter 4. A sealing door 2 is provided on the upper end face and on each layer plate of the multi-layer shielded sealed housing 1, and an opening is provided on the lower end face of the multi-layer shielded sealed housing 1, which can be sealed to the top flange 9 of the reactor vessel. Each layer of the multi-layer shielded sealed housing 1 is connected to the adsorption filter 4 through a sealing through-sleeve 3, and the adsorption filter 4 is fixed to the multi-layer shielded sealed housing 1. When the adsorption filter 4 is opened, gas in each layer of the multi-layer shielded sealed housing 1 can be extracted and filtered through the sealing through-sleeve 3.

[0053] In this way, effective shielding and sealing can be provided during off-site dry refueling and / or maintenance. While shielding against radioactive radiation, the adsorption filter 4 can absorb radioactive gases released during the disassembly and / or refueling of the reactor vessel top cover 8, preventing leakage of radioactive gas products and effectively reducing the risk of radioactive contamination of the plant. Moreover, the shielding device adopts a layered design, with each layer effectively separated, meeting the complex environmental requirements of the refueling and / or maintenance process, while effectively improving the safety of the refueling and / or maintenance process. Furthermore, the adsorption filter 4 can maintain the multi-layered shielded sealing box 1 under negative pressure, which can also provide a sealing and shielding effect for the reactor vessel.

[0054] It should be noted that the number of layers in the multi-layer shielded sealed enclosure 1 is not limited to... Figure 1 The example of two layers can also be any number of layers greater than or equal to one, such as three or four layers. Those skilled in the art can set the specific number of layers in the multi-layer shielded sealing box 1 according to actual needs. Moreover, the sealing through sleeve 3 involved in this invention only represents a pipe that can be sealed and connected to the multi-layer shielded sealing box 1, and is not limited to a sleeve; it can also be other pipes, such as through-sealing pipes. In addition, the opening connecting the multi-layer shielded sealing box 1 to the top of the stack container can also be set in other locations of the multi-layer shielded sealing box 1, such as on the side wall of the multi-layer shielded sealing box 1, and connected to the top of the stack container by setting a transition section. Furthermore, without affecting the sealing and shielding effect, one or more transparent observation windows can be opened at appropriate locations on the multi-layer shielded sealing box 1 to facilitate a direct understanding of the internal situation of the multi-layer shielded sealing box 1.

[0055] like Figure 2 As exemplified, in a preferred embodiment of the shielding device for a reactor provided by the present invention, the adsorption filtration device 4 includes an exhaust pipe 4-1, a vacuum pump 4-4, and a gaseous product filter 4-3. One end of each exhaust pipe 4-1 is connected to a sealed through sleeve 3, and the other end of all exhaust pipes 4-1 is connected to the inlet of the gaseous product filter 4-3. The outlet of the gaseous product filter 4-3 is connected to the suction port of the vacuum pump 4-4, and the exhaust port of the vacuum pump 4-4 is in communication with the environment.

[0056] Thus, when the shielding device used for the reactor is in operation, the radioactive gas products in the multi-layer shielded sealed box 1 can be adsorbed and filtered, and the multi-layer shielded sealed box 1 can be kept under negative pressure to prevent the leakage of radioactive gas products.

[0057] It should be noted that the present invention does not limit the number of gas product filters 4-3 and vacuum pumps 4-4, and those skilled in the art can set one or more according to actual needs. Furthermore, the present invention does not limit the types of gas product filters 4-3 and vacuum pumps 4-4; the vacuum pump 4-4 can be a dry screw vacuum pump, a water ring pump, a reciprocating pump, a slide valve pump, a rotary vane pump, a Roots pump, and a diffusion pump, etc. The gas product filter 4-3 can be a bag filter, a diaphragmless filter, etc., and the gas filter of the present invention is not limited to these.

[0058] like Figure 2 As exemplified, in a preferred embodiment of the present invention, the adsorption filtration device 4 is further provided with a plurality of valves 4-2, with at least one valve 4-2 provided on each discharge pipe, so as to allow independent control of each layer as needed.

[0059] See back Figure 1 In a preferred embodiment of the present invention, the shielding device for a reactor further includes an external overhead crane 5, which is connected to the multi-layer shielded sealed housing 1.

[0060] In a preferred embodiment of the present invention, the shielding device for a reactor further includes an internal overhead crane 6 and a refueling and maintenance mechanism 7. The internal overhead crane 6 and the external overhead crane 5 are horizontally movable relative to each other, and the internal overhead crane 6 is connected to the refueling and maintenance mechanism 7.

[0061] Thus, the overhead crane consists of an external overhead crane 5 and an internal overhead crane 6. The two sets of overhead cranes facilitate the relative movement of the multi-layer shielded sealed box 1 and the material replacement and maintenance mechanism 7 in vertical and horizontal space, and facilitate the removal of the top cover 8 of the stacking container, etc.

[0062] It should be noted that, alternatively, instead of separately providing external and internal overhead cranes 5 and 6, only one overhead crane capable of simultaneous internal and external transport can be installed. In this case, the material changing and maintenance mechanism 7 must be detachably installed with the overhead crane. Furthermore, the internal overhead crane 6 and external overhead crane 5 can be mounted on two independent, horizontally parallel tracks, or the internal overhead crane 6 can be mounted on the frame beam of the external overhead crane 5, or other configurations, allowing them to move relative to each other in the horizontal direction. This invention does not impose any limitations on these configurations.

[0063] See Figure 1 and Figure 4In one embodiment of the present invention, a reactor shielding device includes a refueling and maintenance mechanism 7 comprising a drive mechanism 7-1, a telescopic mechanism 7-2, and a disassembly / reassembly tool 7-3. One end of the drive mechanism 7-1 is connected to an internal overhead crane 6, and the other end is connected to the telescopic mechanism 7-2. The disassembly / reassembly tool 7-3 is located at the bottom of the telescopic mechanism 7-2. A sealing member 7-4 is provided on the telescopic mechanism 7-2, which can be sealed to the sealing door 2 on the upper surface of the multi-layer shielded sealing box 1. Preferably, the sealing member 7-4 is a sealing ring. Preferably, the drive mechanism 7-1 is a motor.

[0064] In this way, the telescopic mechanism 7-2 can retract as needed during operation, saving operating space and making the overall layout of the device more compact. At the same time, the sealing component 7-4 provided on the telescopic mechanism 7-2 can play a sealing role.

[0065] It should be noted that the sealing component 7-4 in this invention can be any other sealing component 7-4 besides the sealing ring 9-1, such as a sealing groove. Furthermore, the drive mechanism of this invention does not limit the specific form of the motor; it can be a push rod motor, a rotary motor, etc.

[0066] In a preferred embodiment of the reactor shielding device provided by the present invention, the telescopic mechanism 7-2 includes a large sleeve 7-2-1 and a lower sleeve 7-2-2. The large sleeve 7-2-1 is connected to the drive mechanism 7-1, and the lower sleeve 7-2-2 is telescopically disposed within the large sleeve 7-2-1. A disassembly and assembly tool 7-3 is disposed at the bottom of the lower sleeve 7-2-2, and a sealing member 7-4 is disposed on the outer surface of the large sleeve 7-2-1. The telescopic mechanism 7-2, using the cooperation of the large sleeve 7-2-1 and the lower sleeve 7-2-2, can easily realize the telescopic function. During hoisting, the lower sleeve 7-2-2 extends out from the large sleeve 7-2-1, and when hoisted away or ready for use, part or all of the lower sleeve 7-2-2 retracts into the large sleeve 7-2-1. Furthermore, during the operation of the shielding device used in the reactor, the sealing component 7-4 is pressed and sealed by the upper sealing door 2 of the multi-layer shielding sealing box 1, ensuring the sealing effect of the box and ensuring the reliable operation of the adsorption filter device 4. Preferably, the lower sleeve 7-2-2 is driven by a screw drive in the larger sleeve 7-2-1, and the sealing component 7-4 is a sealing ring 9-1.

[0067] It should be noted that the telescopic mechanism 7-2 of the present invention is not limited to the structure shown in the figure, which includes a large sleeve 7-2-1 and a lower sleeve 7-2-2. It can also be other forms of mechanisms with retractable and extendable functions, such as a sleeve + pulley rope mechanism, a folding telescopic mechanism, a pulley mechanism, etc. Furthermore, the transmission method of the lower sleeve 7-2-2 within the large sleeve 7-2-1 is not specifically limited; it can be a screw drive or other transmission methods, such as gear and rack drive, pneumatic drive, etc. Next, the disassembly and assembly tool 7-3 can be a general-purpose disassembly and assembly tool or a special disassembly and assembly tool used for refueling and maintenance (in this invention, a special disassembly and assembly tool refers to a comprehensive tool specifically used in the art for disassembling the reactor vessel top cover bolts, disassembling other equipment inside the reactor, and installing fuel assemblies during dry refueling of reactors). Those skilled in the art can choose according to the specific application scenario. Finally, the present invention does not limit the specific structure of the sealing member 7-4; it can also be other types of sealing members 7-4, such as a sealing groove.

[0068] like Figure 4 As illustrated in the example, in a preferred embodiment of the reactor shielding device provided by the present invention, the sealing door 2 is a double door. Each of the two doors has a notch on its opposite sides on the opening side, forming a through-hole allowing the telescopic mechanism 7-2 to pass through. The double-opening design of the sealing door 2 saves operating space when opening it.

[0069] It should be noted that the present invention does not limit the specific shape of the double door; it can be circular or other shapes, such as square. Furthermore, the shape of the notch on the double door is not limited; it can be circular or other shapes. The starting position of the notch is not limited to the example shown in the figure; it can also be opened in other parts of the double door, for example, all on one of the doors. Moreover, the size of the through holes opened on each sealing door 2 can be the same, or different sizes of through holes can be set according to the specific structure of the telescopic mechanism 7-2.

[0070] In a preferred embodiment of the present invention, a shielding device for a reactor is provided, wherein a multi-layer shielding sealing box 1 is pressed against a sealing ring 9-1 provided on the top flange 9 of the reactor vessel, and a sealed connection is formed between the sealing box 1 and the top flange 9 of the reactor vessel.

[0071] It should be noted that the multi-layer shielded sealed enclosure 1 can also be sealed to the top of the stack container via a separately provided transition device, such as an added transition cylinder. Furthermore, the sealing ring 9-1 can be replaced by other sealing components, such as sealing strips.

[0072] Furthermore, such as Figure 3As exemplified, the sealing ring 9-1 includes an inner ring sealing ring 9-1-1 and an outer ring sealing ring 9-1-2. The top cover 8 of the stack container is sealed by the inner ring sealing ring 9-1-1, and the multi-layer shielded sealing box 1 is sealed by the outer ring sealing ring 9-1-2.

[0073] It should be noted that the outer ring seal 9-1-2 and the inner ring seal 9-1-1 can be designed as a single unit or as separate units depending on actual needs. Furthermore, the outer ring seal 9-1-2 can also be installed on the multi-layer shielded sealing housing 1.

[0074] In a preferred embodiment of the present invention, the size of the sealing door 2 for a reactor is larger than the size of the reactor vessel top cover 8, which facilitates the disassembly of the reactor vessel top cover 8.

[0075] In a preferred embodiment of the present invention, the size of the opening on the lower end face of the multi-layer shielded sealing box 1 is larger than the size of the reactor vessel top cover 8, so that the reactor vessel top cover 8 can be lifted out of the shielding device for installation and / or maintenance.

[0076] In a preferred embodiment of the present invention, the shielding device for a reactor includes a first steel plate layer 1-1, a lead shielding layer 1-2, and a second steel plate layer 1-3, which can achieve a good shielding and sealing effect.

[0077] Below, in conjunction with Figure 1 Figure 5 describes a preferred embodiment of the shielding device for a reactor and its operation method.

[0078] like Figures 1-4 The example shielding device for the reactor includes a multi-layer shielded sealed housing 1, a sealed through sleeve 3, an adsorption filter 4, an external gantry crane 5 connected to the multi-layer shielded sealed housing 1, an internal gantry crane 6, and a refueling and maintenance mechanism 7. The internal gantry crane 6 and the external gantry crane 5 can move relative to each other in the horizontal direction. The internal gantry crane 6 is connected to the refueling and maintenance mechanism 7. The adsorption filter 4 is fixed on the double-layer shielded sealed housing. The multi-layer shielded sealing box 1 is configured as a double-layer sealing box (including an upper layer and a lower layer). Sealing doors 2 are provided on the upper end surface of the double-layer sealing box and the second layer plate. Sealing doors 2 are circular double doors (circular refers to the shape of sealing door 2 when closed). The double doors are arranged opposite each other, and each side of the opening side of the two doors of the double-door sealing box 2 is provided with a notch. The notch is a semi-circular hole. The two semi-circular holes form a circular through hole that allows the telescopic mechanism 7-2 to pass through. The size of the through hole on the upper double-door sealing box 2-1 matches the size of the large sleeve 7-2-1, and the size of the through hole on the lower double-door sealing box 2-2 matches the size of the lower sleeve 7-2-2. The size of the double doors is larger than the size of the top cover 8 of the stack container.

[0079] The adsorption filtration device 4 includes an exhaust pipe 4-1, a vacuum pump 4-4, and a gas product filter 4-3. One end of each exhaust pipe 4-1 is connected to a sealed through sleeve 3. Each layer of the double-layer shielded sealed housing is connected to the adsorption filtration device 4 through a sealed through sleeve 3. The other end of each exhaust pipe 4-1 is connected to the inlet of the gas product filter 4-3. The outlet of the gas product filter 4-3 is connected to the suction port of the vacuum pump 4-4, and the exhaust port of the vacuum pump 4-4 is connected to the environment. The adsorption filtration device 4 is also equipped with multiple valves 4-2, one valve 4-2 on each exhaust pipe. Specifically, this includes an upper control valve 4-2-1 controlling the upper layer of the double-layer sealed housing and an upper control valve 4-2-2 controlling the lower layer of the double-layer sealed housing. When the adsorption filtration device 4 is opened, the gas in each layer of the double-layer shielded sealed housing can be extracted and filtered through the sealed through sleeve 3.

[0080] The material replacement and maintenance mechanism 7 includes a drive mechanism 7-1, a telescopic mechanism 7-2, and a disassembly and assembly tool 7-3. One end of the drive mechanism 7-1 is connected to the internal overhead crane 6, and the telescopic mechanism 7-2 is connected to the other end of the drive mechanism 7-1. The disassembly and assembly tool 7-3 is located at the bottom of the telescopic mechanism 7-2 and is a dedicated disassembly and assembly tool. The telescopic mechanism 7-2 includes a large sleeve 7-2-1 and a lower sleeve 7-2-2. The large sleeve 7-2-1 is connected to the drive mechanism 7-1, and the lower sleeve 7-2-2 is telescopically mounted within the large sleeve 7-2-1. The disassembly and assembly tool 7-3 is located at the bottom of the lower sleeve 7-2-2. A sealing component 7-4 (e.g., a sealing ring 9-1) is located on the outer surface of the large sleeve 7-2-1. The lower sleeve 7-2-2 is driven by a screw drive within the large sleeve 7-2-1. The lower end face of the double-layer shielded sealing enclosure has an opening that is sealed to the top flange 9 of the reactor vessel. The size of the opening is larger than the size of the reactor vessel top cover 8. The multi-layer shielded sealing enclosure 1 achieves a sealed connection with the top flange 9 of the reactor vessel by a sealing ring 9-1 pressed onto the top flange 9. The sealing ring 9-1 includes an inner ring sealing ring 9-1-1 and an outer ring sealing ring 9-1-2. The reactor vessel top cover 8 is sealed by the inner ring sealing ring 9-1-1, and the multi-layer shielded sealing enclosure 1 is sealed by the outer ring sealing ring 9-1-2. The multi-layer shielded sealing enclosure 1 and each layer of the enclosure include a first steel plate layer 1-1, a lead shielding layer 1-2, and a second steel plate layer 1-3.

[0081] The following is combined with Figure 5a and Figure 5b This describes one possible implementation of the shielding device for a reactor provided in the embodiments of the present invention. Figure 5aThis is a schematic diagram of a reactor shielding device provided in an embodiment of the present invention during operation, showing the state in which the lower double-opening sealing door is open and the lower sleeve with top cover enters the upper sealed shielding box. Figure 5b This is another schematic diagram of a reactor shielding device provided in an embodiment of the present invention during operation, showing the state in which the lower double-opening sealing door is closed, the upper double-opening sealing door is open, and the top cover of the sling is lifted out of the sealed box.

[0082] Taking the removal and reinstallation of the reactor vessel top cover 8 as an example, the operation method of the shielding device for reactors of the present invention is explained. Specifically, the process is described in two parts: disassembly and removal, and installation.

[0083] Disassembly and hoisting process: First, the double-layer shielded sealed enclosure is moved to the top of the reactor vessel, so that the opening on the lower end face of the double-layer shielded sealed enclosure is sealed to the top of the reactor through the outer ring sealing ring 9-1-2. Then, the external gantry crane 5 and the internal gantry crane 6 are positioned, and the refueling and maintenance mechanism 7 is positioned (specifically, the drive mechanism 7-1 drives the lower sleeve 7-2-2 to extend from the upper sleeve, and the special disassembly and assembly tool 7-3 is in standby mode). After the double-layer shielded sealed enclosure and the top of the reactor vessel are sealed together, a shielded sealed space is constructed for dry refueling and maintenance of the reactor. After the reactor vessel has undergone multiple rounds of flushing with coolant and gas exchange, the connecting bolts on the reactor vessel top cover 8 are removed using the special disassembly and assembly tool. When the reactor vessel top cover 8 begins to open, the adsorption filter device 4 is triggered to operate. Then, the drive mechanism 7-1 drives the lower sleeve 7-2-2 to move upward and gradually retract, opening the reactor vessel top cover 8. At this point, the adsorption filter 4 absorbs the radioactive gas products released due to the movement of the reactor vessel top cover 8. Once the radioactive gas products in the lower layer of the double-layer shielded sealed enclosure reach the permissible level, the lower double-opening sealing door 2-2 opens, and the lower sleeve 7-2-2 continues to move upwards and gradually retracts, lifting the reactor vessel top cover 8 out of the lower sealed shielded enclosure and into the upper layer of the double-layer shielded sealed enclosure. Subsequently, the lower double-opening sealing door 2-2 is closed, and the through-hole of the lower sleeve 7-2-2 on the lower double-opening sealing door 2-2 is sealed, providing a sealing shield for the reactor vessel from the lower layer. Furthermore, the adsorption filter 4 can also maintain the lower sealed shielded enclosure under negative pressure, further enhancing its sealing shielding effect on the reactor vessel. After the radioactive gas products in the upper layer of the double-layer shielded sealed box reach the allowable value, the upper control valve 4-2-1 of the adsorption filter device 4 is closed, the upper double-opening sealed door 2-1 is opened, and the internal crane 6 lifts the material replacement and maintenance mechanism 7 and the top cover of the stack container 8 out of the double-layer shielded sealed box, and then closes the upper double-opening sealed door 2-1.

[0084] It should be noted that after the top cover 8 of the reactor vessel is lifted out, the upper double-opening sealing door 2-1 of the lower layer of the double-layer shielded sealing box can also be in the open state. After the top cover 8 of the reactor vessel is lifted out, the adsorption filter device 4 can be closed, relying on the negative pressure state of the lower and / or upper layers of the double-layer shielded sealing box to prevent the leakage of radioactive gas products; alternatively, only the upper control valve 4-2-2 can be opened; or both the upper control valve 4-2-1 (when the upper double-opening sealing door 2-1 is also in the closed state) and the upper control valve 4-2-2 can be opened simultaneously.

[0085] The process of removing spent fuel or other critical equipment within the reactor for maintenance is basically the same as the process of removing the reactor container top cover 8 mentioned above.

[0086] The hoisting and installation process: The hoisting and installation of the reactor vessel top cover 8, the installation of new fuel assemblies, or the hoisting and installation of other critical equipment within the reactor are the reverse of the disassembly and hoisting operations. The hoisting and installation of the reactor vessel top cover 8 will be used as an example for explanation. First, open the upper double-opening sealing door 2-1. Drive mechanism 7-1 drives the lower sleeve 7-2-2 of the material replacement and maintenance mechanism 7 to gradually extend from the large sleeve 7-2-1 to the top cover 8 of the stacking container. After the top cover 8 of the stacking container falls to the upper layer of the double-layer shielded sealing box, close the upper double-opening shielding door 2-1. Open the upper control valve 4-2-1 of the adsorption filter device 4 and open the lower double-opening sealing door 2-2. Drive mechanism 7-1 drives the lower sleeve 7-2-2 of the material replacement and maintenance mechanism 7 to continue extending from the large sleeve 7-2-1 to the top cover 8 of the stacking container. After the top cover 8 of the stacking container is completely inserted into the lower layer of the double-layer shielded sealing box, close the lower double-opening sealing door 2-2. Drive mechanism 7-1 drives the lower sleeve 7-2-2 of the material replacement and maintenance mechanism 7 to continue extending from the large sleeve 7-2-1 to the top cover 8 of the stacking container until it is in place. Then the material replacement and maintenance mechanism 7 completes the installation of the top cover 8 of the stacking container.

[0087] When using the shielding device for reactors provided by this invention for dry refueling or maintenance processes, the multi-layered shielded sealed enclosure 1 can shield against radiation, and the adsorption and filtration device 4 can absorb radioactive gas products released during the disassembly and refueling of the reactor vessel top cover 8. Overall, this effectively reduces or even eliminates the risk of radioactive contamination of the reactor building, meets the complex environmental requirements of refueling and maintenance equipment, and improves the safety of refueling and maintenance processes. Moreover, the entire refueling and maintenance process can be carried out remotely without any radioactive impact on the reactor building.

[0088] Those skilled in the art will understand that although some embodiments herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of the invention and form different embodiments. For example, in the claims of the invention, any of the claimed embodiments can be used in any combination.

[0089] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will all fall within the scope of protection of the present invention.

Claims

1. A shielding device for a reactor, characterized in that, Includes a multi-layer shielded sealed enclosure, a sealed through-sleeve, and an adsorption filtration device; The upper end face of the multi-layer shielded sealing box and each layer plate are provided with a sealing door. The lower end face of the multi-layer shielded sealing box is provided with an opening that can be sealed to the top flange of the stacking container. Each layer of the multi-layer shielded sealing box is connected to the adsorption filtration device through a sealing through sleeve. The adsorption filtration device is fixed on the multi-layer shielded sealed box, and The adsorption filtration device is configured to extract and filter the gas in each layer of the multi-layer shielded sealed box through the sealed through sleeve when opened; It also includes an external overhead crane, which is connected to the multi-layer shielded and sealed enclosure. It also includes an internal overhead crane and a material changing and maintenance mechanism, wherein the internal overhead crane and the external overhead crane can move relative to each other in the horizontal direction, and the internal overhead crane is connected to the material changing and maintenance mechanism; The material replacement and maintenance mechanism includes a drive mechanism, a telescopic mechanism, and disassembly / assembly tools; One end of the drive mechanism is connected to the internal overhead crane, the telescopic mechanism is connected to the other end of the drive mechanism, and the disassembly and assembly tool is located at the bottom of the telescopic mechanism.

2. The shielding device for a reactor according to claim 1, characterized in that, The adsorption filtration device includes an external discharge pipe, a vacuum pump, and a gas product filter; One end of each of the exhaust pipes is connected to a sealing through sleeve, and the other end of each of the exhaust pipes is connected to the inlet of the gas product filter. The outlet of the gas product filter is connected to the suction port of the vacuum pump, and the exhaust port of the vacuum pump is in communication with the environment.

3. The shielding device for a reactor according to claim 2, characterized in that, The adsorption filtration device is also equipped with multiple valves, one of which is installed on each of the external discharge pipelines.

4. The shielding device for a reactor according to claim 1, characterized in that, The telescopic mechanism is equipped with a sealing component, which can be sealed to the sealing door on the upper surface of the multi-layer shielded sealing box.

5. The shielding device for a reactor according to claim 4, characterized in that, The telescopic mechanism includes a large sleeve and a lower sleeve; The large sleeve is connected to the driving mechanism, the lower sleeve is telescopically disposed in the large sleeve, the disassembly and assembly tool is disposed at the bottom of the lower sleeve, and the sealing member is disposed on the outer surface of the large sleeve.

6. The shielding device for a reactor according to claim 1, wherein the sealing door is a double door, the double doors are arranged opposite to each other and each side on the opening side is provided with a notch, and the two notches surround to form a through hole allowing the telescopic mechanism to pass through.

7. The shielding device for a reactor according to claim 1, characterized in that, The multi-layer shielded sealing enclosure achieves a sealed connection with the top flange of the stack container by a sealing ring pressed onto the top flange of the stack container; and / or The size of the sealing door is larger than the size of the top cover of the stacking container; and / or The size of the opening is larger than the size of the top cover of the stack container.

8. The shielding device for a reactor according to claim 1, characterized in that, The multi-layer shielded sealed enclosure and each layer of the enclosure include a first steel plate layer, a lead shielding layer, and a second steel plate layer.

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