Mechanical removal device of high temperature gas cooled reactor spent fuel coated particle cladding layer and method thereof

Abstract

This invention belongs to the field of special robot technology, specifically relating to a mechanical removal device for the coating layer of spent fuel particles in a high-temperature gas-cooled reactor. The device includes an automatic feeding platform (1), a grinding disc device (2), a suction device (3), a waste collection box (4), and a coated particle core collection box (5). The automatic feeding platform (1) is used to temporarily hold coated particles and push the particles requiring coating removal above the grinding disc device (2); the grinding disc device (2) is used to grind the coated particles located in the grinding holes (1.3), removing their coating layer and causing the waste to fall off; the waste collection box (4) is used to collect the coating waste removed by the grinding disc device (2); and the coated particle core collection box (5) is used to collect the fuel cores whose coating layers have all been removed. This method uses mechanical grinding to remove each coating layer, and while removing each layer, it separates and collects different waste materials, facilitating subsequent waste processing. The method is simple and easy to implement.

Description

Technical Field

[0001] This invention relates to the field of special robot technology, and more specifically, to a device and method for mechanically removing the coating layer of spent fuel particles from a high-temperature gas-cooled reactor. Background Technology

[0002] The spent fuel particles coated in high-temperature gas-cooled reactors have a five-layer structure. The first and third layers are high-density pyrolytic carbon layers, the second layer is silicon carbide, and the fourth layer is a loose pyrolytic carbon layer. The core is the UO2 nuclear fuel. The spent fuel coated particle mechanical removal device is used at the front end of spent fuel reprocessing to remove the coated layers of spent fuel particles layer by layer. It has the advantages of simple structure, convenient operation, and high efficiency. Without affecting the fuel core, it grinds and removes each coated layer, collects and decontaminates the waste, and finally recovers the fuel core.

[0003] Currently, devices used for coating removal include fluidized bed combustion units, hammer crushers, jet mills, and devices for various chemical removal methods. Fluidized bed combustion units remove pyrolytic carbon layers through combustion; this method is simple and feasible, but it produces CO2 containing radioactive elements, requiring further treatment of the exhaust gas. Hammer crushers are used to crush silicon carbide coatings; the method is relatively simple, but hammer crushers experience significant wear, particle size is difficult to control, and the recovery rate cannot reach 100%. Jet mills are simple and feasible, requiring no exhaust gas treatment, but they suffer from severe wear during operation, material limitations, slow crushing speed, and low efficiency. Chemical removal methods require highly corrosion-resistant containers and post-processing of the products, and currently face a series of problems. The removal process of spent fuel coating particles is complex, and the removal effect is not ideal, making the recovery and processing of fuel cores difficult. Current commercially available decoating devices for removing coated particles have discontinuous processes and operate under high conditions. This invention proposes a mechanical decoating device and method for removing coated particles from high-temperature gas-cooled reactors, which can achieve continuous layer-by-layer removal of the coating and achieve excellent removal and filtration effects. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides: 1. A mechanical removal device for the coating layer of spent fuel particles in a high-temperature gas-cooled reactor, comprising an automatic feeding platform, a grinding disc device, a suction device, a waste collection box, and a coated particle core collection box, characterized in that:

[0005] The automatic feeding platform is used to temporarily hold coated particles and push the coated particles that need to have their coating removed to the top of the grinding disc device;

[0006] The grinding disc device is used to grind the coated particles located in the abrasive holes, remove their coating, and cause the waste to fall off.

[0007] The suction device is used to extract coated particles from the previous station, after one layer of coating has been removed, to the next station. The suction device includes a filter plate, a vacuum generator, and a suction pipe. The filter plate covers the abrasive holes and has corresponding smaller diameter filter holes for each abrasive hole, with the filter plate in direct contact with the abrasive holes. The vacuum generator is connected to the filter plate and is located above the filter plate. Every minute, a vacuum negative pressure is generated above the filter plate to adsorb the qualified coated particles that can pass through the filter holes. The suction pipe is connected to the vacuum generator and transports the coated particles adsorbed by the vacuum generator to the storage tank of the next automatic feeding station.

[0008] The waste collection bin is used to collect the coating waste removed by the grinding disc device;

[0009] The coated particle core collection box is used to collect fuel cores whose coating has been removed.

[0010] Furthermore, the automatic feeding platform includes a material storage tank, a material spreading plate, and an abrasive hole;

[0011] The automatic feeding platform is fixed on the ground. The storage tank is located at one end of the automatic feeding platform and is used to temporarily hold the coated particles that need to have their coating removed. The spreading plate is a rectangular frame located inside the storage tank. It is controlled by a hydraulic device and can move along the storage tank to push the coated particles to fill the abrasive holes and pull the excess coated particles back to the storage tank. The abrasive holes are located at one end of the storage tank and are used to place the coated particles so that the grinding disc can remove the coating evenly.

[0012] Furthermore, the grinding disc device includes a grinding disc, a push rod, and a drive module; the grinding disc is located directly below the abrasive hole and in the middle of two adjacent automatic feeding platforms, and has a small gap with the abrasive hole, for grinding away the coating layer of the coated particles located in the abrasive hole; the grinding disc has small channels, so that the ground waste falls through the channels into the waste collection box located below the grinding disc.

[0013] The push rod is connected to the grinding disc and the drive module, and is used to drive the grinding disc to move below the abrasive hole to remove the coating layer;

[0014] The drive module consists of a drive motor and a cam mechanism, which converts the rotation of the motor output shaft into the linear reciprocating motion of the push rod, thereby driving the grinding disc to move.

[0015] Furthermore, the waste collection box is located directly below the grinding disc and between two adjacent automatic feeding platforms, and is used to collect the coating grinding waste that falls through the small holes on the grinding disc.

[0016] Furthermore, the coated pellet fuel core collection box is located on one side of the No. 1 automatic feeding platform and is used to collect fuel cores whose coating has been completely removed.

[0017] The invention also provides a method for mechanically removing the coating layer of spent fuel particles from a high-temperature gas-cooled reactor, characterized by the following steps:

[0018] Step 1: After the coated particles enter the storage tank of the corresponding station of the automatic feeding table, the spreading plate evenly spreads the coated particles that need to have their coating removed into the grinding holes for grinding.

[0019] Step 2: The motor drives the telescopic arm of the grinding disc device to move, thereby driving the grinding disc to move and grind off the coating layer of the coated particles located in the upper abrasive hole. At the same time, the ground powder waste falls into the waste collection box below through the small holes on the grinding disc.

[0020] Step 3: After the coating layer of the coated particles is removed by grinding, they are sucked into the next station by the suction device until the last coating layer is removed, and then sucked into the fuel core collection box.

[0021] After the grinding wheel has been grinding for one minute, the suction device will grind off one layer of coating particles, and then suck them up through the filter plate and transport them to the storage tank of the next automatic feeding platform. For the coating particles that have had the fourth layer of loose pyrolytic carbon removed, the remaining fuel core will be sucked into the coating particle fuel core collection box. The coating particles that have not had their corresponding coating layer ground off cannot pass through the filter holes and will continue to remain in the grinding holes.

[0022] Step 4: After each suction, the suction device will rise a certain distance to make room for the material spreading plate. Then the material spreading plate will push the coated particles to fill the abrasive holes, and the above steps will be repeated.

[0023] Furthermore, in step 2: after the graphite matrix of the spent fuel element is removed, the separated coated particles are placed in the storage tank of the No. 1 automatic feeding platform. After each grinding process to remove one layer of coating, the particles will fall into the storage tank of the next automatic feeding platform through the suction device until the fourth layer of loose pyrolytic carbon is removed and then sucked into the fuel core collection box.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0025] Compared with existing methods for removing spent fuel coatings from particles, this method uses mechanical grinding to remove each coating layer, and separates and collects different waste materials while removing them in layers, which facilitates subsequent waste treatment. The method is simple and easy to implement.

[0026] The device of this invention uses a mechanical method to remove the coating layer, and removes the coating layer of the coated particles layer by layer in an assembly line manner. It has a simple and compact structure and high practicality. Attached Figure Description

[0027] The advantages of the above and / or additional aspects of this application will become apparent and readily understood in the description of the embodiments in conjunction with the following drawings, wherein:

[0028] Figure 1 This is a schematic diagram of the overall structure of the coating layer removal device of the present invention;

[0029] Figure 2 This is an assembly diagram of the automatic feeding platform and grinding disc device of the present invention;

[0030] Figure 3 This is an assembly diagram of the automatic feeding platform and grinding disc device of the present invention;

[0031] Figure 4 This is an assembly diagram of the automatic feeding platform and filter plate of the present invention;

[0032] Figure 5 This is a schematic diagram of the material laying panel of the present invention;

[0033] Among them: 1-Automatic feeding platform: 1.1-Storage tank: 1.1.1-Storage tank No. 1, 1.1.2-Storage tank No. 2, 1.1.3-Storage tank No. 3, 1.1.4-Storage tank No. 4; 1.2-Padded plate; 1.3-Abrasive hole; 2-Grinding disc device: 2.1-Grinding disc; 2.2-Push rod; 2.3-Drive module; 3-Suction device: 3.1-Filter plate; 3.2-Vacuum generator; 3.3-Suction pipe; 4-Waste collection box; 5-Coated particle core collection box. Detailed Implementation

[0034] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings and examples. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0035] like Figure 1 As shown, this embodiment provides a mechanical removal device for the coating layer of spent fuel particles in a high-temperature gas-cooled reactor. The device includes an automatic feeding platform 1, a grinding disc device 2, a suction device 3, a waste collection box 4, and a coating particle core collection box 5.

[0036] The automatic feeding platform 1 is used to temporarily hold coated particles and push the coated particles that need to have their coating removed to the top of the grinding disc device 2;

[0037] The grinding disc device 2 is used to grind the coated particles located in the abrasive hole 1.3, remove their coating layer and cause the waste to fall off;

[0038] The suction device 3 is used to suction the coated particles that have had one layer of coating removed from the previous station to the next station;

[0039] Waste collection bin 4 is used to collect the coating waste removed by the grinding disc device 2;

[0040] The coated particle core collection box 5 is used to collect fuel cores whose coating layers have been removed.

[0041] The automatic feeding platform 1 includes a storage tank 1.1, a feeding plate 1.2, and an abrasive hole 1.3.

[0042] The automatic feeding platform 1, as the main body of the device, is fixed to the ground. The storage trough 1.1 is located at one end of the automatic feeding platform and is used to temporarily hold coated particles whose coating layer needs to be removed; for example... Figure 5 As shown, the material spreading plate 1.2 is a rectangular frame located inside the material storage tank 1.1. It is controlled by a hydraulic device and can move along the material storage tank 1.1 to push the coated particles to fill the abrasive holes 1.3 and pull the excess coated particles back to the material storage tank 1.1. The abrasive holes 1.3 are located at one end of the material storage tank 1.1 and are used to place the coated particles so that the grinding disc 2.1 can remove the coating layer evenly.

[0043] Furthermore, the grinding disc device 2 includes a grinding disc 2.1, a push rod 2.2, and a drive module 2.3.

[0044] The grinding disc 2.1 is located directly below the abrasive hole 1.3 and between two adjacent automatic feeding tables 1, with a small gap between it and the abrasive hole 1.3. It is used to grind away the coating layer of the coated particles located within the abrasive hole 1.3. Figure 3 As shown, the grinding disc 2.1 has many small channels, which allow the waste material to fall into the waste collection box 4 located below the grinding disc 2.1 through the channels; the push rod 2.2 is connected to the grinding disc 2.1 and to the drive module 2.3, and is used to drive the grinding disc 2.1 to move below the abrasive hole 1.3 to remove the coating layer; the drive module 2.3 is composed of a drive motor and a cam mechanism, which converts the rotation of the motor output shaft into the linear reciprocating motion of the push rod 2.2, thereby driving the grinding disc to move.

[0045] Furthermore, the suction device 3 includes a filter plate 3.1, a vacuum generator 3.2, and a suction pipe 3.3.

[0046] like Figure 2As shown, since the device has multiple stations to remove the coating layer layer by layer, multiple grinding and suction processes are required. A filter plate 3.1 covers the abrasive holes 1.3 and has corresponding smaller diameter filter holes for each abrasive hole 1.3, used to filter coated particles whose corresponding coating layers have been completely removed. The filter plate 3.1 is in direct contact with the abrasive holes 1.3 to prevent coated particles from popping out during the coating removal process. A vacuum generator 3.2 is connected to the filter plate 3.1 and is located above the filter plate 3.1. Every minute, a vacuum negative pressure is generated above the filter plate 3.1, adsorbing the qualified coated particles that can pass through the filter holes. The suction pipe 3.3 is connected to the vacuum generator 3.2, transporting the coated particles adsorbed by the vacuum generator 3.2 to the storage tank 1.1 of the next automatic feeding platform 1. The fuel cores adsorbed by the suction device 3 through the filter plate 3.1 are transported to the coated particle fuel core collection box 5 through the suction pipe 3.3.

[0047] Furthermore, the waste collection box 4 is located directly below the grinding disc 2.1 and between two adjacent automatic feeding platforms 1, and is used to collect the coating grinding waste that falls through the small holes on the grinding disc 2.1.

[0048] Furthermore, the coated pellet fuel core collection box 5 is located on one side of the No. 1 automatic feeding platform 1 and is used to collect fuel cores whose coating has been completely removed.

[0049] This invention provides a method for mechanically removing the particulate coating layer from spent fuel in a high-temperature gas-cooled reactor, characterized by the following steps:

[0050] Step 1: After the coated particles enter the storage tank 1.1 of the corresponding station of the automatic feeding table 1, the spreading plate 1.2 evenly spreads the coated particles that need to have their coating removed into the grinding hole 1.3 for grinding.

[0051] After the graphite matrix is ​​removed from the spent fuel element, the separated coated particles are placed in the storage tank 1.1.1 of the No. 1 automatic feeding platform 1. After each grinding process to remove one layer of coating, the particles will fall into the storage tank 1.1 of the next automatic feeding platform 1 through the suction device 3, until the fourth layer of loose pyrolytic carbon is removed and then sucked into the fuel core collection box 5.

[0052] The spreading plate 1.2 pushes the coated particles to the abrasive hole 1.3. Under the action of gravity, the coated particles fall into the abrasive hole 1.3 and come into contact with the grinding disc 2.1 located below, filling the abrasive hole 1.3 with coated particles. Then the spreading plate 1.2 is pulled back to collect the excess coated particles into the storage tank 1.1. Then the filter plate 3.1 of the suction device 3 is placed directly above the abrasive hole 1.3.

[0053] Step 2: The motor 2.3 drives the telescopic arm 2.2 of the grinding disc device 2 to move, thereby driving the grinding disc 2.1 to move and grind away the coating layer of the coated particles located in the upper abrasive hole 1.3. At the same time, the ground powder waste falls into the waste collection box 4 below through the small holes on the grinding disc 2.1.

[0054] Step 3: After the coating layer of the coated particles is removed by grinding, they are sucked into the next station by the suction device 3. After the last coating layer is ground off, they are sucked into the fuel core collection box 5.

[0055] After the grinding disc 2.1 grinds for one minute, the suction device 3 will grind off one layer of coating particles, and then suck them up through the filter plate 3.1 and transport them to the storage tank 1.1 of the next automatic feeding platform 1. For the coating particles that have had the fourth layer of loose pyrolytic carbon removed, the remaining fuel core will be sucked into the coating particle fuel core collection box 5. The coating particles that have not had their corresponding coating layer ground off cannot pass through the filter holes and will continue to remain in the grinding hole 1.3.

[0056] Step 4: After each suction, the suction device 3 will rise a certain distance to make room for the material spreading plate 1.2. Then the material spreading plate 1.2 will push the coated particles to fill the abrasive holes 1.3, and the above steps will be repeated.

[0057] The above descriptions are merely embodiments of the present invention, and common knowledge regarding specific structures and characteristics of the solutions is not described in detail here. It will be apparent to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the present invention is defined by the appended claims rather than the foregoing description. Therefore, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A high-temperature gas-cooled reactor spent fuel coated particle coating layer mechanical removal device, the device comprising an automatic feeding table (1), a grinding disc device (2), a suction device (3), a waste collection box (4), a coated particle core collection box (5), characterized in that: the automatic feeding table (1) is used to temporarily place coated particles and push the coated particles that need to remove the coating layer above the grinding disc device (2); the grinding disc device (2) is used to grind the coated particles in the grinding hole (1.3), remove the coating layer and make the waste fall off; the suction device (3) is used to suck the coated particles that have removed a layer of coating layer in the previous station to the next station; the suction device (3) comprises a filter plate (3.1), a vacuum generator (3.2) and a suction pipeline (3.3); the filter plate (3.1) covers above the grinding hole (1.3) and has a corresponding smaller filter hole for each grinding hole (1.3), and the filter plate (3.1) is in direct contact with the grinding hole (1.3); the vacuum generator (3.2) is connected with the filter plate (3.1) and located above the filter plate (3.1), and every interval of one minute, a vacuum negative pressure is generated above the filter plate (3.1) to suck the qualified ground coated particles that can pass through the filter hole; the suction pipeline (3.3) is connected with the vacuum generator (3.2) to transport the coated particles sucked by the vacuum generator (3.2) to the storage groove (1.1) of the next automatic feeding table (1); the waste collection box (4) is used to collect the coating layer waste removed by the grinding disc device (2); and the coated particle core collection box (5) is used to collect the fuel core whose coating layer has been removed.

2. The high-temperature gas-cooled reactor spent fuel coated particle coating layer mechanical removal device according to claim 1, characterized in that: the automatic feeding table (1) comprises a storage groove (1.1), a material laying fence (1.2) and a grinding hole (1.3); the automatic feeding table (1) is fixed on the ground, the storage groove (1.1) is at one end of the automatic feeding table and is used to temporarily place the coated particles that need to remove the coating layer; the material laying fence (1.2) is a rectangular frame located in the storage groove (1.1) and can move along the storage groove (1.1) to push the coated particles to fill the grinding hole (1.3) and pull back the excess coated particles to the storage groove (1.1); and the grinding hole (1.3) is located at one end of the storage groove (1.1) and is used to place the coated particles so that the grinding disc (2.1) can uniformly remove the coating layer.

3. The high-temperature gas-cooled reactor spent fuel coated particle coating layer mechanical removal device according to claim 1, characterized in that: ​ ​ ​ ​ ​ ​ ​ ​ The grinding disc device (2) comprises a grinding disc (2.1), a push rod (2.2), and a driving module (2.3); the grinding disc (2.1) is located directly below the abrasive hole (1.3) and in the middle of the adjacent two automatic material placing tables (1), and has a small gap with the abrasive hole (1.3) for grinding off the coating layer of the coated particles in the abrasive hole (1.3); the grinding disc (2.1) has small holes for the ground waste to fall into the waste collecting box (4) below the grinding disc (2.1); The push rod (2.2) is connected with the grinding disc (2.1) and connected with the driving module (2.3) for driving the grinding disc (2.1) to move below the abrasive hole (1.3) to remove the coating layer; The driving module (2.3) is composed of a driving motor and a cam mechanism, which converts the rotation of the motor output shaft into the linear reciprocating motion of the push rod (2.2), thereby driving the grinding disc to move.

4. The mechanical coating layer removing device for coated particles of spent fuel of a high-temperature gas cooled reactor according to claim 1, characterized in that: The waste collecting box (4) is located directly below the grinding disc (2.1) and in the middle of the adjacent two automatic material placing tables (1) for collecting the coating layer grinding waste falling through the small holes on the grinding disc (2.1).

5. The mechanical coating layer removing device for coated particles of spent fuel of a high-temperature gas cooled reactor according to claim 1, characterized in that: The coated particle fuel core collecting box (5) is located on one side of the first automatic material placing table (1) for collecting the fuel core after the coating layer is completely removed.

6. A method for mechanical removal of a cladding layer of a high temperature gas cooled reactor spent fuel coated particle, characterized in that The method comprises the following steps: Step 1: After the coated particles enter the corresponding work position of the automatic material placing table (1), the laying surrounding board (1.2) uniformly lays the coated particles needing to remove the coating layer in the abrasive hole (1.3) for grinding; Step 2: The driving module (2.3) drives the push rod (2.2) of the grinding disc device (2) to move, thereby driving the grinding disc (2.1) to move, grinding off the coating layer of the coated particles in the upper abrasive hole (1.3), and at the same time, the ground powder waste falls into the waste collecting box (4) below through the small holes on the grinding disc (2.1); Step 3: After the coated particles remove one layer of coating layer, they are sucked into the next work position through the suction device (3), and after the last layer of coating layer is ground off, they are sucked into the fuel core collecting box (5); After the grinding disc (2.1) grinds for one minute, the coated particles with one layer of coating layer removed are sucked by the suction device (3) and conveyed to the storage tank (1.1) of the next automatic material placing table (1) through the filter plate (3.1); the fuel core left after the fourth layer of loose pyrolytic carbon is removed is sucked into the coated particle fuel core collecting box (5), and the coated particles without the corresponding coating layer removed cannot pass through the filter hole and will continue to be left in the abrasive hole (1.3); Step 4: After each suction, the suction device (3) rises by a distance to leave space for the laying surrounding board (1.2), and then the laying surrounding board (1.2) pushes the coated particles to fill the abrasive hole (1.3), and the above steps are repeated.

7. The high temperature gas cooled reactor spent fuel coated particle blanket layer mechanical removal method according to claim 6, characterized by, In step 2, the coated particles separated from the spent fuel elements after the graphite matrix is removed are placed in the storage tank (1.1) of the first automatic placing table (1), and after each grinding to remove a layer of the coating, they are dropped into the storage tank (1.1) of the next automatic placing table (1) through the suction device (3) until the fourth layer of loose pyrolytic carbon is removed and is sucked into the fuel core collection box (5). ​

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