Crushing and screening device for uranium dioxide pellets and powder

Abstract

The invention belongs to the technical field of nuclear power, and particularly relates to a crushing and screening device for uranium dioxide pellets and powder. Aiming at a series of problems of semi-open operation, low automation level, large manual operation amount, incapability of meeting radiation health protection requirements and the like in crushing and screening of blocky uranium-containing waste materials such as uranium dioxide pellets, the invention provides a method for pretreating the uranium-containing waste materials for the first time. The functions of airtight vacuum conveying, crushing, screening and quantitative subpackaging of uranium-containing waste are integrally achieved. Operators set functional parameters such as the rotating speed of the pulverizer and the split charging weight in advance through remote control, automatic operation of the device can be achieved under the condition of continuous feeding, due to the fact that the crushing and screening part is provided with a sealed compartment, and the feeding and discharging part is arranged in a negative pressure glove box, the overall sealing performance of the device is better, and the service life of the device is prolonged. Uranium dioxide pellets and powder can be efficiently crushed and screened in a sealed environment, and the national and industrial radiation health protection requirements are met.

Description

Technical Field

[0001] The invention belongs to the technical field of nuclear power, and in particular relates to a crushing and screening device for uranium dioxide pellets and powder. Background Art

[0002] In the process of manufacturing nuclear fuel elements, it is necessary to crush and screen the spent uranium dioxide pellets, spent uranium dioxide powder and spent powder containing broken pellets, crush the blocky waste into particles of ~0.4mm, and remove foreign matter to meet the needs of production and recycling. If such uranium-containing waste is not handled in time, a large amount of uranium resources will be deposited, and there will be a high criticality safety risk. Therefore, recycling uranium-containing waste has huge social benefits and economic value.

[0003] At present, there are only devices in China that can crush and screen uranium dioxide powder and powder containing broken core blocks. The existing uranium chemical recovery line cannot directly recycle bulk uranium-containing waste such as waste uranium dioxide core blocks. Due to the high hardness of uranium dioxide core blocks, they are not directly crushed. The method used is to directly oxidize the uranium dioxide core blocks into uranium trioxide powder at a high temperature of 650°C. This method has low processing efficiency, high equipment energy consumption, and large floor space. In addition, the current device for crushing and screening uranium-containing waste is a semi-open operating equipment with a low level of automation and a large amount of manual operation, which cannot meet the requirements of radiation health protection. Therefore, it is urgent to improve the efficiency of crushing uranium dioxide core blocks and powders. Summary of the invention

[0004] In order to overcome the problems existing in the related art, a crushing and screening device for uranium dioxide pellets and powder is provided.

[0005] According to one aspect of an embodiment of the present disclosure, there is provided a crushing and screening device for uranium dioxide pellets and powder, the device comprising: a loading glove box, a vacuum conveyor, a vibrating screen, a pulverizer, a unloading glove box, a vacuum unit, a weight sensor and a controller;

[0006] The controller is used to control the vacuum conveyor, vibrating screen, pulverizer, weight sensor and vacuum unit; a suction gun is arranged in the loading glove box, which is used to automatically and sealedly convey the uranium-containing waste to the vacuum conveyor under the drive of the vacuum unit; the vacuum conveyor conveys the received uranium-containing waste to the vibrating screen, and after the vibrating screening, the large particles of waste fall into the waste bucket on the screen in the unloading glove box, and the small particles of waste pass through the vibrating screen and fall into the pulverizer below the vibrating screen;

[0007] The pulverizer is used to crush the falling waste at a preset speed; the qualified waste after crushing falls through the screen into the discharging barrel connected to the discharging pipe in the discharging glove box until the weight of the discharging barrel is detected by the weight sensor to be close to the set weight, and the controller controls the closing of the discharging pipe.

[0008] In one possible implementation, the device is arranged in an axial space with a top platform, a middle platform and a lower platform in order from top to bottom, the vacuum conveyor is placed on the top platform, the vibrating screen and the crusher are placed on the middle platform, and the loading glove box, the unloading glove box and the vacuum unit are placed on the bottom platform.

[0009] In a possible implementation, the distance between the top platform and the middle platform is 1.95 m, and the distance between the middle platform and the bottom platform is 2.20 m.

[0010] In a possible implementation, the following steps are used to crush and screen the uranium dioxide pellets and powder:

[0011] Step 11: The operator transports the barrel containing the uranium waste to the production site, places the barrel into a preset position in the loading glove box, closes the feeding door of the loading glove box, opens the upper cover of the barrel, and inserts the suction gun into the barrel;

[0012] Step 12: The operator pushes the sub-packaging barrel into the glove box, opens the barrel cover, completes the docking operation of the material discharge pipe, closes the feed door of the glove box, and then clears the weighing sensor corresponding to the sub-packaging barrel;

[0013] Step 13, start the vacuum conveying system, the operator controls the crusher, vibrating screen and vacuum conveyor to start respectively on the operation control interface, and starts the material extraction operation after the negative pressure of the vacuum conveyor reaches the set value;

[0014] Step 14, the waste materials conveyed by vacuum are directly fed into the vibrating screen by the vacuum conveyor. After being screened by the vibrating screen, the large waste particles fall into the waste bucket on the screen in the glove box for unloading, and the small waste particles pass through the vibrating screen and fall into the crusher below the vibrating screen.

[0015] Step 15, the crusher crushes the falling waste at a preset speed; the crushed qualified waste falls into the buffer silo through the screen;

[0016] Step 16, the discharge pipe of the buffer silo is connected to the rotary valve of the unloading glove box, and when the waste material in the buffer silo is higher than the low material level, the rotary valve is started to perform the discharge operation;

[0017] Step 17, during the process of the rotary valve discharging the material quickly, when the controller detects through the weight sensor corresponding to the sub-packaging barrel that the weight of the sub-packaging barrel is close to the set weight, the controller controls the discharging speed of the rotary valve to gradually slow down until the weight of the sub-packaging barrel reaches the set weight, and then closes the rotary valve to stop discharging;

[0018] Step 18, the controller controls the unloading pipe in the unloading glove box to lift up, let it stand for a preset time, and perform a static check on the sub-packaging barrel through a weight sensor;

[0019] Step 19, when the controller determines through static review that the weight of the sub-filling barrel reaches the set weight, the unloading pipe is separated from the sub-filling barrel, and the conveyor belt is controlled to move the sub-filling barrel away;

[0020] Repeat steps 11 to 19 to achieve efficient crushing and screening of uranium dioxide pellets and powder.

[0021] The beneficial effect of the present disclosure is that compared with the existing waste crushing and screening equipment in the workshop, the present disclosure integrates the sealed vacuum conveying, crushing and screening and quantitative packaging functions of uranium-containing waste for the first time in the uranium-containing waste pretreatment process. By utilizing equipment automation, the operator sets the functional parameters such as the pulverizer speed and the packaging weight in advance through remote control, so that the automatic operation of the device can be realized under the condition of continuous feeding, and the manual operation amount is relatively reduced. Since the crushing and screening part is provided with a sealed compartment, and the feeding and discharging parts are arranged in a negative pressure glove box, the overall sealing performance of the device is better, and the radiation health protection level at the job site is higher. In this way, the device of the present disclosure realizes the feeding, crushing and screening and quantitative packaging of uranium-containing waste in a sealed environment, meeting the radiation health protection requirements stipulated by the state and the industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of a crushing and screening device for uranium dioxide pellets and powder shown in an embodiment of the present disclosure.

[0023] In the figure:

[0024] 1: Loading glove box; 2: Vacuum conveyor; 3: Vibrating screen; 4: Crusher; 5: Unloading glove box;

[0025] 6: Vacuum unit; 7: Buffer tank. DETAILED DESCRIPTION

[0026] The present disclosure is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] Unless otherwise defined, the technical and scientific terms used in the present disclosure have the same meanings as those generally understood by those skilled in the art to which the present disclosure belongs; the terms used in the present disclosure are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure; the term "including" and any variations thereof in the present disclosure are intended to cover non-exclusive inclusions. Obviously, the embodiments described in the present disclosure are only part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in the field without making creative efforts are within the scope of protection of the present disclosure.

[0028] Reference to "embodiments" in this disclosure means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the disclosure. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0029] Figure 1 Schematic diagram of a crushing and screening device for uranium dioxide pellets and powders shown in an embodiment of the present disclosure, such as Figure 1 As shown, the device 101 includes: a loading glove box 1, a vacuum conveyor 2, a vibrating screen 3, a crusher 4, a unloading glove box 5, a vacuum unit 6, a buffer tank 7, a weight sensor and a controller.

[0030] In the axial space of device 101, a top platform, a middle platform and a lower platform are arranged in order from top to bottom. The distance between the top platform and the middle platform is 1.95m, and the distance between the middle platform and the bottom platform is 2.20m. The vacuum conveyor 2 is placed on the top platform, the vibrating screen 3 and the crusher 4 are placed on the middle platform, the loading glove box 1, the unloading glove box 5, the vacuum unit 6 and the buffer tank 7 are placed on the bottom platform, realizing a modular layout of the device, which is convenient for personnel operation and maintenance.

[0031] The controller is used to control the vacuum conveyor 2, the vibrating screen 3, the pulverizer 4, the weight sensor and the vacuum unit 6. A suction gun 3 is arranged in the loading glove box 1, which is used to automatically and sealedly convey the uranium-containing waste to the vacuum conveyor 2 under the drive of the vacuum unit 6; the vacuum conveyor 2 is used to convey the received uranium-containing waste to the vibrating screen 3, and the large particles of waste fall into the waste bucket on the screen in the unloading glove box 5 after being screened by the vibrating screen 3, and the small particles of waste pass through the vibrating screen 3 and fall into the pulverizer 4 below the vibrating screen 3;

[0032] The pulverizer 4 is used to crush the falling waste at a preset speed; the crushed qualified waste falls through the screen into the discharging barrel connected to the discharging pipe in the discharging glove box 5 until the weight of the discharging barrel is detected by the weight sensor to be close to the set weight, and the controller controls the closing of the discharging pipe.

[0033] The crushing and screening device for uranium dioxide core blocks and powder provided by the present disclosure is aimed at the problems of low automation degree of the equipment and large amount of manual operation. First, the various functional equipment involved in the crushing and screening device are systematically integrated. In the axial space, the top platform, the middle platform and the lower platform are arranged in order from top to bottom. The vacuum conveyor is placed on the top platform, the vibrating screen and the crushing equipment are placed on the middle platform, and the loading and unloading glove boxes and vacuum supporting equipment are placed on the bottom platform to realize the modular layout of the device, which is convenient for personnel operation and maintenance; in terms of equipment selection, a vacuum feeding system is selected, and an automatic feeding gun is used to automatically and sealedly convey uranium-containing waste to the vacuum conveyor to reduce the amount of manual operation; a universal crusher (crushing and screening integrated machine) with a crushing fineness of 0-120 mesh is selected to effectively shorten the uranium-containing waste treatment process; with the help of a control system, the operation status of the workstation is monitored in real time, and the equipment operation parameters are adjusted online to realize the integrated control of vacuum feeding, vibration screening, crushing and unloading links.

[0034] In view of the problem that semi-open operation cannot meet the requirements of radiation health protection on site, the present invention improves the inherent sealing of the crushing and screening device by reselecting the equipment on the one hand; on the other hand, the crushing and screening links where waste leakage may occur are sealed and isolated, and the loading and unloading links where waste is open are operated through a negative pressure glove box to ensure that the radioactive dust in the workplace is effectively isolated.

[0035] In terms of equipment selection, the present invention adopts a vacuum feeding system, and uses an automatic feeding gun to automatically and sealedly transport the uranium-containing waste to the vacuum conveyor, reducing the amount of manual operation; a universal crusher (crushing and screening all-in-one machine) with a crushing fineness of 0-120 mesh is selected to effectively shorten the uranium-containing waste treatment process; with the help of a control system, the operating status of the workstation is monitored in real time, and the equipment operating parameters are adjusted online to achieve integrated control of vacuum feeding, vibration screening, crushing and discharging links.

[0036] Based on the device disclosed in the present invention, the following steps are adopted to crush and screen the uranium dioxide pellets and powder.

[0037] Step 11, the operator transports the barrel containing the uranium waste to the production site, puts the barrel into a preset position in the loading glove box 1, closes the feed door of the loading glove box 1, opens the upper cover of the barrel, and inserts the suction gun into the barrel.

[0038] Step 12, the operator pushes the sub-packaging barrel for sub-packaging into the unloading glove box 5, opens the barrel cover, completes the unloading pipeline docking operation, closes the feed door of the unloading glove box 5, and then clears the weighing sensor corresponding to the sub-packaging barrel;

[0039] Step 13, start the vacuum conveying system. The operator at the post controls the start-up of the crusher 4, the vibrating screen 3 and the vacuum conveyor 2 respectively on the operation control interface. After the negative pressure of the vacuum conveyor 2 reaches the set value, the material extraction operation begins. The material extraction follows the principle of small amounts and multiple times to ensure that the waste conveying system will not be blocked.

[0040] Step 14, the waste material conveyed by vacuum is directly sent to the vibrating screen 3 by the vacuum conveyor. After being screened by the vibrating screen 3, the large waste particles fall into the waste bucket on the screen in the unloading glove box 5, and the small waste particles pass through the vibrating screen 3 and fall into the crusher 4 below the vibrating screen 3.

[0041] Step 15, the pulverizer 4 crushes the falling waste at a preset speed; the crushed qualified waste passes through the screen and falls into the buffer silo.

[0042] Step 16, the discharge pipe of the buffer silo is connected to the rotary valve of the unloading glove box 5, and when the waste material in the buffer silo is higher than the low material level, the rotary valve is started to perform the discharge operation.

[0043] Step 17, during the process of the rotary valve discharging the material quickly, when the controller detects through the weight sensor corresponding to the sub-packaging barrel that the weight of the sub-packaging barrel is close to the set weight, the controller controls the discharging speed of the rotary valve to gradually slow down until the weight of the sub-packaging barrel reaches the set weight, and then closes the rotary valve to stop discharging;

[0044] Step 18, the controller controls the unloading pipe in the unloading glove box 5 to lift up, let it stand for a preset time (for example, 3 seconds), and statically review the sub-packaging barrel through the weight sensor, thereby achieving accurate review after removing waste impact and connection interference, which helps to weigh more accurately.

[0045] Step 19, when the controller determines through static review that the weight of the sub-filling barrel reaches the set weight, the unloading pipe is separated from the sub-filling barrel, and the conveyor belt is controlled to move the sub-filling barrel away.

[0046] Repeat steps 11 to 19 to achieve efficient crushing and screening of uranium dioxide pellets and powder.

[0047] Compared with the existing waste crushing and screening equipment in the workshop, the present invention integrates the sealed vacuum conveying, crushing and screening, and quantitative packaging functions of uranium-containing waste for the first time in the uranium-containing waste pretreatment process. By utilizing equipment automation, the operator can set the functional parameters such as the pulverizer speed and packaging weight in advance through remote control, so that the device can be operated automatically under the condition of continuous feeding, and the manual operation amount is relatively reduced. Since the crushing and screening part is provided with a sealed compartment, and the feeding and discharging parts are arranged in a negative pressure glove box, the overall sealing performance of the device is better, and the radiation health protection level at the job site is higher. In this way, the device disclosed in the present invention realizes the feeding, crushing and screening, and quantitative packaging of uranium-containing waste in a sealed environment, meeting the radiation health protection requirements stipulated by the state and the industry.

[0048] The embodiments of the present disclosure have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A crushing and screening device for uranium dioxide pellets and powder, characterized in that: The device comprises: a loading glove box, a vacuum conveyor, a vibrating screen, a pulverizer, a unloading glove box, a vacuum unit, a weight sensor and a controller; The controller is used to control the vacuum conveyor, vibrating screen, pulverizer, weight sensor and vacuum unit; a suction gun is arranged in the loading glove box, which is used to automatically and sealedly convey the uranium-containing waste to the vacuum conveyor under the drive of the vacuum unit; the vacuum conveyor conveys the received uranium-containing waste to the vibrating screen, and after the vibrating screening, the large particles of waste fall into the waste bucket on the screen in the unloading glove box, and the small particles of waste pass through the vibrating screen and fall into the pulverizer below the vibrating screen; The pulverizer is used to crush the falling waste at a preset speed; the qualified waste after crushing falls through the screen into the discharging barrel connected to the discharging pipe in the discharging glove box until the weight of the discharging barrel is detected by the weight sensor to be close to the set weight, and the controller controls the closing of the discharging pipe.

2. The device according to claim 1, characterized in that The device is arranged in the axial space with a top platform, a middle platform and a lower platform in order from top to bottom, the vacuum conveyor is placed on the top platform, the vibrating screen and the crusher are placed on the middle platform, and the loading glove box, the unloading glove box and the vacuum unit are placed on the bottom platform.

3. The device according to claim 2, characterized in that The distance between the top platform and the middle platform is 1.95m, and the distance between the middle platform and the bottom platform is 2.20m.

4. The device according to claim 1, characterized in that The crushing and screening of uranium dioxide pellets and powders are carried out in the following steps: Step 11: The operator transports the barrel containing the uranium waste to the production site, places the barrel into a preset position in the loading glove box, closes the feeding door of the loading glove box, opens the upper cover of the barrel, and inserts the suction gun into the barrel; Step 12: The operator pushes the sub-packaging barrel into the glove box, opens the barrel cover, completes the docking operation of the material discharge pipe, closes the feed door of the glove box, and then clears the weighing sensor corresponding to the sub-packaging barrel; Step 13, start the vacuum conveying system, the operator controls the crusher, vibrating screen and vacuum conveyor to start respectively on the operation control interface, and starts the material extraction operation after the negative pressure of the vacuum conveyor reaches the set value; Step 14, the waste materials conveyed by vacuum are directly fed into the vibrating screen by the vacuum conveyor. After being screened by the vibrating screen, the large waste particles fall into the waste bucket on the screen in the glove box for unloading, and the small waste particles pass through the vibrating screen and fall into the crusher below the vibrating screen. Step 15, the crusher crushes the falling waste at a preset speed; the crushed qualified waste falls into the buffer silo through the screen; Step 16, the discharge pipe of the buffer silo is connected to the rotary valve of the unloading glove box, and when the waste material in the buffer silo is higher than the low material level, the rotary valve is started to perform the discharge operation; Step 17, during the process of the rotary valve discharging the material quickly, when the controller detects through the weight sensor corresponding to the sub-packaging barrel that the weight of the sub-packaging barrel is close to the set weight, the controller controls the discharging speed of the rotary valve to gradually slow down until the weight of the sub-packaging barrel reaches the set weight, and then closes the rotary valve to stop discharging; Step 18, the controller controls the unloading pipe in the unloading glove box to lift up, let it stand for a preset time, and perform a static check on the sub-packaging barrel through a weight sensor; Step 19, when the controller determines through static review that the weight of the sub-filling barrel reaches the set weight, the unloading pipe is separated from the sub-filling barrel, and the conveyor belt is controlled to move the sub-filling barrel away; Repeat steps 11 to 19 to achieve efficient crushing and screening of uranium dioxide pellets and powder.

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