Spent fuel post-treatment waste cladding decontamination device
Through the combined design of a spherical box and an ultrasonic generator, combined with acidic decontamination solution and heavy metal elution chelating agent, the problem of unsatisfactory decontamination effect of spent fuel reprocessing waste cladding was solved, and efficient radioactive material removal and waste volume reduction were achieved.
Patent Information
- Application Number
- CN202510833276.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-20
- Publication Date
- 2025-09-26
AI Technical Summary
The decontamination effect of spent fuel reprocessing waste cladding in the existing technology is not ideal, and it is difficult to effectively remove radioactive substances on the surface.
A spherical box design is adopted, and multiple ultrasonic generators are arranged in an array along the circumference of the box to form a high-intensity linear focused ultrasonic area. Combined with acidic decontamination solution and heavy metal elution chelating agent, the ultrasonic cavitation effect and chemical corrosion synergistic effect are used to strip off the radioactive substances on the surface of the spent cladding.
The decontamination efficiency and effect of spent cladding were significantly improved, surface radioactive materials were removed quickly and effectively, and radioactivity degradation and volume reduction were achieved.
Smart Images
Figure CN120708959A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of spent fuel reprocessing, and in particular to a spent fuel reprocessing waste cladding decontamination device. Background Art
[0002] In the wet reprocessing of spent fuel, after the spent fuel assemblies undergo shearing, dissolution, and leaching, the remaining insoluble solid waste is called spent cladding. Currently, the cladding material for light water reactor spent fuel is zirconium-4 alloy.
[0003] Spent cladding is the primary source of high-level solid waste at the beginning of the wet spent fuel reprocessing process due to factors such as activation of materials during irradiation within the reactor, recoil of fission products into the cladding matrix, and the presence of residual materials from the reprocessing process (including transuranic nuclides such as uranium, plutonium, curium, and americium, as well as fission products). Spent cladding is highly radioactive and is the primary source of high-level solid waste at the beginning of the wet spent fuel reprocessing process. To achieve radioactivity degradation and volume reduction of this solid waste, decontamination of the spent cladding is essential.
[0004] At present, the decontamination methods for post-processing waste cladding usually include chemical decontamination, electrochemical decontamination, etc., but the decontamination effects of these decontamination methods are not ideal. Summary of the Invention
[0005] In view of this, an embodiment of the present invention provides a spent fuel reprocessing waste cladding decontamination device, the main purpose of which is to improve the decontamination effect of the reprocessing waste cladding.
[0006] To achieve the above objectives, the present invention mainly provides the following technical solutions:
[0007] An embodiment of the present invention provides a spent fuel reprocessing waste cladding decontamination device, comprising:
[0008] A box body, the box body is spherical and contains a decontamination solution;
[0009] A plurality of ultrasonic generators, wherein the plurality of ultrasonic generators are arranged in an array along the circumference of the box on the outer wall of the box;
[0010] A basket body is arranged in the box body and located in the spherical center area of the box body. The basket body is immersed in the decontamination solution, and the post-processing waste cladding is placed in the basket body.
[0011] Furthermore, the ultrasonic generator is tightly fitted to the outer wall of the box.
[0012] Furthermore, the basket is spherical, and the center of the basket coincides with the center of the box.
[0013] Furthermore, the decontamination solution is an acidic solution system.
[0014] Further, the decontamination solution is a nitric acid solution;
[0015] A heavy metal eluting chelating agent is added to the decontamination solution.
[0016] Furthermore, the spent fuel reprocessing waste cladding decontamination device further includes:
[0017] A temperature control component is used to heat the decontamination solution and control the temperature of the decontamination solution to a preset temperature, which is 30-100°C.
[0018] Furthermore, the spent fuel reprocessing waste cladding decontamination device further includes:
[0019] A driving portion is connected to the basket body in driving connection, and is used for driving the basket body to rotate relative to the box body.
[0020] Furthermore, the spent fuel reprocessing waste cladding decontamination device further includes:
[0021] A support body is detachably connected to the box body and is used to support the box body.
[0022] Furthermore, an opening is provided on the top of the box, and the opening is used for the basket to enter or leave the box;
[0023] The box body is provided with a cover body, and the cover body is used to open or close the opening.
[0024] Furthermore, the frequency of the ultrasonic generator is 20-90 kHz.
[0025] By means of the above technical solution, the present invention has at least the following beneficial effects:
[0026] In the spent fuel reprocessing cladding decontamination device provided in an embodiment of the present invention, a spherical housing is provided. A plurality of ultrasonic generators are arranged in an array along the circumference of the housing on the outer wall of the housing. A basket containing the spent fuel cladding is disposed within the housing and located in the spherical center region of the housing. As a result, ultrasonic waves emitted by each ultrasonic generator can radiate radially toward the basket region of the housing. That is, the radiation direction of the ultrasonic waves is directed toward the basket region, thereby forming a high-intensity linear focused ultrasonic wave region at the basket region, covering the spent fuel cladding to be decontaminated within the basket. The cavitation effect of the ultrasonic wave is utilized to strip away radioactive material loosely attached to the surface of the spent fuel cladding. Furthermore, a decontamination solution is stored within the housing, and the basket is immersed in the decontamination solution. The decontamination solution can activate, dissolve, or rinse radioactive material on the surface of the spent fuel cladding. The radioactive material on the surface of the spent fuel cladding is loosened through chemical corrosion. The synergistic effect of the high-intensity focused ultrasonic wave can quickly and effectively strip away the loose radioactive material on the surface of the spent fuel cladding, thereby improving the decontamination efficiency and effectiveness. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present invention. The same reference numerals are used throughout the accompanying drawings to denote the same components.
[0028] Figure 1 A schematic structural diagram of a spent fuel reprocessing waste cladding decontamination device provided in an embodiment of the present invention;
[0029] Figure 2 A schematic structural diagram of another spent fuel reprocessing waste cladding decontamination device provided in an embodiment of the present invention. DETAILED DESCRIPTION
[0030] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions in the embodiments of the present invention will be described in more detail below with reference to the accompanying drawings of preferred embodiments of the present invention. Some embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following embodiments and features of the embodiments may be combined with each other unless there is any conflict.
[0031] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.
[0032] like Figure 1 or Figure 2As shown, an embodiment of the present invention provides a spent fuel reprocessing waste cladding decontamination device, comprising a spherical box 1 storing a decontamination solution 2; a plurality of ultrasonic generators 3 arranged in an array along the circumference of the box 1 on the outer wall of the box 1; a basket 4 disposed in the box 1 and located in the spherical center area of the box 1, the basket 4 being immersed in the decontamination solution 2, and the reprocessing waste cladding 5 being placed in the basket 4.
[0033] The housing 1 is spherical, with spherical inner and outer walls. Multiple ultrasonic generators 3 are arranged in an array along the circumference of the housing 1 on its outer wall. This allows the ultrasonic waves emitted by each ultrasonic generator 3 to be directed toward the basket 4. In other words, the spherical structure of the housing 1 constrains the directivity of the ultrasonic radiation, directing the ultrasonic waves toward the center of the housing 1. This allows the ultrasonic waves to be focused onto the basket 4, thereby forming an arc-shaped, high-intensity ultrasonic region around the basket 4. In other words, a high-intensity, linearly focused ultrasonic region is formed at the basket 4, generating the strongest resonance. This ultrasonic region covers the basket 4, utilizing the cavitation effect of ultrasonic waves. This is when ultrasonic waves act on the decontamination solution 2, generating numerous tiny bubbles. These tiny bubbles expand and contract strongly with ultrasonic vibrations, generating pressure exceeding one thousand atmospheres at the moment of sudden rupture. This forms microjets, which in turn remove radioactive materials, such as radionuclides or particulates, loosely adhering to the surface of the reprocessing waste cladding 5.
[0034] The intensity of the cavitation effect is related to the power and frequency of the ultrasonic generator 3. The higher the power and the lower the frequency of the ultrasonic generator 3, the higher the cavitation intensity. A longer time or higher intensity cavitation effect can form cavitation corrosion on the surface of the post-processing waste cladding 5, thereby further stripping off the radioactive substances on the surface of the post-processing waste cladding 5 to achieve the purpose of further decontamination.
[0035] Among them, the decontamination solution 2 can be used to activate, dissolve or rinse the radioactive substances on the surface of the post-processing waste cladding 5, and through chemical corrosion, the radioactive substances remaining, attached or deposited on the surface of the post-processing waste cladding 5 become loose, thereby helping the ultrasonic wave to peel off the radioactive substances on its surface. Correspondingly, the high-intensity linear focused ultrasound uses the cavitation effect to peel off the loose radioactive substances on the surface of the post-processing waste cladding 5, and also helps the decontamination solution 2 to corrode the radioactive substances on the surface of the post-processing waste cladding 5. Therefore, the present application utilizes the synergistic effect of high-intensity focused ultrasound and chemical corrosion of the decontamination solution 2 to enhance the decontamination effect on the post-processing waste cladding 5, and provide reliable technical support for the radioactive decontamination and degradation disposal of the post-processing waste cladding 5.
[0036] In the spent fuel reprocessing waste cladding decontamination device provided by the embodiment of the present invention, the box body 1 is spherical, and a plurality of ultrasonic generators 3 are arranged in an array along the circumference of the box body 1 on the outer wall of the box body 1. The basket body 4 containing the spent fuel reprocessing waste cladding 5 is arranged in the box body 1 and is located in the spherical center area of the box body 1. As a result, the ultrasonic waves emitted by each ultrasonic generator 3 can be radiated toward the basket body 4 area along the radial direction of the box body 1, that is, the radiation direction of the ultrasonic waves is directed toward the basket body 4 area, thereby forming a high-intensity linear focused ultrasonic wave area at the basket body 4, covering the spent fuel reprocessing waste cladding to be decontaminated in the basket body 4. The cladding 5 utilizes the cavitation effect of ultrasound to peel off the radioactive substances loosely attached to the surface of the post-processing waste cladding 5. Moreover, a decontamination solution 2 is stored in the box 1, and the basket 4 is immersed in the decontamination solution 2. The decontamination solution 2 can activate, dissolve or rinse the radioactive substances on the surface of the post-processing waste cladding 5, and make the radioactive substances on the surface of the post-processing waste cladding 5 loose through chemical corrosion. Under the synergistic effect of high-intensity focused ultrasound, the loose radioactive substances on the surface of the post-processing waste cladding 5 can be quickly and effectively peeled off, thereby improving the decontamination efficiency and decontamination effect.
[0037] In some embodiments, see Figure 1 or Figure 2 The ultrasonic generator 3 is in close contact with the outer wall of the box body 1, thereby reducing the radiation loss of the ultrasonic wave and allowing the ultrasonic wave to be radiated to the basket body 4 area as much as possible, so as to be used to peel off the radioactive substances on the surface of the loose post-processing waste cladding 5, thereby further improving the decontamination effect of the post-processing waste cladding 5.
[0038] There are many ways to connect the ultrasonic generator 3 and the box body 1, such as bolt connection, bonding, etc. In order to ensure a close fit between the two, the two can be bonded with adhesive.
[0039] It is understood that the basket 4 has a porous structure so that the post-processed waste cladding 5 can be immersed in the decontamination solution 2. Moreover, the shape of the basket 4 can be any shape, such as a cube or a sphere, as long as the basket 4 is located in the center area of the housing 1 so that the ultrasound can be focused on the basket 4 area.
[0040] In some embodiments, see Figure 2 The basket 4 can be spherical, and the center of the basket 4 coincides with the center of the box 1, so that the basket 4 is located in the high-intensity focused ultrasonic region, thereby facilitating the post-processing waste cladding 5 to be in the strongest ultrasonic resonance region, thereby further improving the decontamination effect of the post-processing waste cladding 5.
[0041] In some embodiments, the decontamination solution 2 can be an acidic solution system, specifically, an acidic solution system that does not contain F-1. This is more conducive to loosening the radioactive material on the surface of the post-processing waste cladding 5 through chemical corrosion. Furthermore, since the decontamination solution 2 is an acidic solution system and does not use hydrogen fluoride (HF) or F-1-containing reagents, the decontamination solution 2 has good compatibility with the post-processing plant waste liquid system and is more practical. Specifically, the decontamination solution 2 can be a nitric acid (HNO3) solution.
[0042] In some embodiments, a heavy metal elution chelating agent may be added to the decontamination solution 2 to enhance the elution efficiency of radioactive substances on the surface of the post-processing waste cladding 5 and further improve the decontamination effect. Specifically, a heavy metal elution chelating agent such as ethylenediaminetetraacetic acid (EDTA) may be added to the decontamination solution 2.
[0043] In order to further improve the decontamination speed, in some embodiments, the spent fuel reprocessing waste cladding decontamination device may further include a temperature control component, which is used to heat the decontamination solution 2 and control the temperature of the decontamination solution 2 to a preset temperature.
[0044] By increasing the chemical reaction temperature of the decontamination solution 2, the chemical corrosion of the radioactive material on the surface of the post-processing waste cladding 5 by the decontamination solution 2 is accelerated, causing the radioactive material to become loose quickly, thereby accelerating the decontamination speed of the post-processing waste cladding 5 by the decontamination solution 2. Specifically, the preset temperature of the decontamination solution 2, i.e., its temperature adjustment range, can be 30-100°C.
[0045] The temperature control assembly can have various structural forms, as long as it can heat and temperature-control the decontamination solution 2. For example, the temperature control assembly can include a temperature sensor, a heater, and a controller, with the temperature sensor and heater being electrically connected to the controller. The temperature sensor is configured to detect the temperature of the decontamination solution 2 and provide real-time feedback of the detected temperature information to the controller. The controller can then control the heater to adjust the heating power based on the temperature information provided by the temperature sensor, thereby controlling the temperature of the decontamination solution 2 within a range of 30-100°C.
[0046] In order to further improve the decontamination speed and decontamination effect, in some embodiments, the spent fuel reprocessing waste cladding decontamination device may further include a driving unit, which is drivably connected to the basket body 4 and is used to drive the basket body 4 to rotate relative to the box body 1.
[0047] During the decontamination operation, the driving unit can be controlled to drive the basket body 4 to rotate relative to the box body 1, so that the post-processing waste cladding 5 in the basket body 4 can be more fully in contact with the decontamination solution 2, thereby further improving the chemical corrosion rate and corrosion effect of the decontamination solution 2 on the radioactive substances on the surface of the post-processing waste cladding 5, thereby making the radioactive substances looser, and further improving the decontamination speed and decontamination effect of the decontamination device.
[0048] The driving unit may be disposed within the housing 1, with its output end connected to the bottom of the basket 4, thereby driving the basket 4 to rotate relative to the housing 1; alternatively, the driving unit may be disposed outside the housing 1 and connected to the basket 4 via a transmission mechanism. For example, the transmission mechanism may include a first magnet and a second magnet having opposite magnetic properties, wherein the first magnet is disposed outside the housing 1 and connected to the output end of the driving unit, and the second magnet is disposed inside the housing 1 and connected to the bottom of the basket 4. The first magnet and the second magnet are magnetically connected, thereby enabling the driving unit to drive the basket 4 to rotate relative to the housing 1. Specifically, the driving unit may be a motor.
[0049] It can be understood that if factors such as the possibility that the driving part may be corroded in the decontamination solution 2 are not considered, a solution in which the driving part is arranged inside the box 1 and connected to the basket 4 can be adopted; if factors such as the driving part being easily corroded in the decontamination solution 2 are considered, a solution in which the driving part is arranged outside the box 1 and connected to the basket 4 through a transmission mechanism can be adopted. The above solutions can be selected according to actual usage requirements.
[0050] In some embodiments, see Figure 1 or Figure 2 The spent fuel reprocessing waste cladding decontamination device may further include a support body 6 , which is detachably connected to the box body 1 and is used to support the box body 1 .
[0051] The support body 6 provides support for the box body 1, thereby buffering the vibration caused by the multiple ultrasonic generators 3, thereby reducing or avoiding the noise generated by the decontamination device.
[0052] Moreover, the support body 6 is detachably connected to the housing 1, which facilitates maintenance and repair of the decontamination device. It is understood that there are many ways to detachably connect the support body 6 to the housing 1, such as bolt connection, snap connection, etc.
[0053] The support body 6 can have various structural forms, as long as it can provide support for the box body 1 to buffer the vibration caused by the ultrasonic generator 3. For example, the support body 6 can be a shell structure, and the box body 1 is connected to the shell, and the shell supports the box body 1, and the box body 1 and the ultrasonic generator 3 are at a certain distance from the ground (or other supporting surface).
[0054] In some embodiments, see Figure 1 or Figure 2 The top of the box body 1 may be provided with an opening 11 for allowing the basket body 4 to enter or leave the box body 1 ; a cover is provided on the box body 1 for opening or closing the opening 11 .
[0055] By opening an opening 11 at the top of the box body 1, the user can place the basket body 4 containing the post-processing waste shells 5 into the box body 1 through the opening 11. Correspondingly, after the decontamination is completed, the basket body 4 can also be taken out of the box body 1 through the opening 11, thereby taking out the post-processing waste shells 5 after decontamination, which is convenient to operate.
[0056] By providing a cover for opening or closing the opening 11, the cover can be used to close the opening 11 during the decontamination operation, thereby preventing the decontamination solution 2 from splashing out through the opening 11, thereby preventing the decontamination solution 2 from splashing and causing environmental pollution. It also avoids wasting the decontamination solution 2, ensuring that the post-processing waste cladding 5 can be immersed in the decontamination solution 2, thereby improving the reliability of the decontamination. Of course, after the decontamination is completed, the cover can be opened to remove the basket 4 through the opening 11.
[0057] The frequency and power density of the ultrasonic generator 3 are adjustable. Specifically, the frequency adjustment range of the ultrasonic generator 3 can be 20-90 KHz.
[0058] It can be understood that based on the spent fuel reprocessing waste cladding decontamination device provided in the embodiment of the present invention, process parameters such as the formula of the decontamination solution 2, the frequency and power of the ultrasonic generator 3, the height of the basket 4 within the housing 1, the rotational speed of the basket 4, and the temperature of the decontamination solution 2 can be specifically adjusted according to the specific characteristics of the components to be decontaminated placed in the basket 4. This can make the spent fuel reprocessing waste cladding decontamination device suitable for decontaminating solid waste in a variety of scenarios. Specifically, the decontamination device can be used to decontaminate radioactive solid waste generated by nuclear power plants, nuclear fuel production facilities, nuclear waste treatment facilities, nuclear medical testing, etc., and can also be used to decontaminate non-radioactive solid waste in non-nuclear fields.
[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.
Claims
1. A spent fuel reprocessing waste cladding decontamination device, characterized in that: include: A box body, the box body is spherical and contains a decontamination solution; A plurality of ultrasonic generators, wherein the plurality of ultrasonic generators are arranged in an array along the circumference of the box on the outer wall of the box; A basket body is arranged in the box body and located in the spherical center area of the box body. The basket body is immersed in the decontamination solution, and the post-processing waste cladding is placed in the basket body.
2. The spent fuel reprocessing waste cladding decontamination device according to claim 1, characterized in that: The ultrasonic generator is tightly fitted to the outer wall of the box.
3. The spent fuel reprocessing waste cladding decontamination device according to claim 1, characterized in that: The basket is spherical, and the center of the basket coincides with the center of the box.
4. The spent fuel reprocessing waste cladding decontamination device according to claim 1, characterized in that: The decontamination solution is an acidic solution system.
5. The spent fuel reprocessing waste cladding decontamination device according to claim 4, characterized in that: The decontamination solution is a nitric acid solution; A heavy metal eluting chelating agent is added to the decontamination solution.
6. The spent fuel reprocessing waste cladding decontamination device according to claim 1, characterized in that: Also includes: A temperature control component is used to heat the decontamination solution and control the temperature of the decontamination solution to a preset temperature, which is 30-100°C.
7. The spent fuel reprocessing waste cladding decontamination device according to claim 1, characterized in that: Also includes: A driving portion is connected to the basket body in driving connection, and is used for driving the basket body to rotate relative to the box body.
8. The spent fuel reprocessing waste cladding decontamination device according to claim 1, characterized in that: Also includes: A support body is detachably connected to the box body and is used to support the box body.
9. The spent fuel reprocessing waste cladding decontamination device according to claim 1, characterized in that: The top of the box is provided with an opening, and the opening is used for the basket to enter or leave the box; The box body is provided with a cover body, and the cover body is used to open or close the opening.
10. The spent fuel reprocessing waste cladding decontamination device according to claim 1, characterized in that: The frequency of the ultrasonic generator is 20-90 kHz.