Radioactive waste immobilization device and immobilization method using the same

Abstract

To provide a radioactive waste immobilization device which offers reinforced radioactive waste storage safety by immobilizing radioactive waste contained in a high-integrity container, and a radioactive waste immobilization method using same.SOLUTION: A radioactive waste immobilization device according to an embodiment of the present invention is designed to immobilize an upper portion of radioactive waste in a high-integrity container so as to prevent the radioactive waste stored in the high-integrity container from leaking out, and may comprise a polymer resin injection unit for injecting a polymer resin for immobilization into the radioactive waste contained in the high-integrity container to form a polymer resin layer, a polymer resin sensing unit for measuring the lamination thickness of the polymer resin layer; to adjust the injection amount of the polymer resin, and a photo-curing unit for curing the polymer resin layer.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to an immobilization device for radioactive waste, which is used to immobilize radioactive waste contained in a high-integrity container and enhance and improve the storage stability of radioactive waste.

Background Art

[0002] Generally, a high-integrity container for storing radioactive waste is composed of a drum for containing radioactive waste and a lid for sealing the drum. When the radioactive waste is contained in the drum, the lid is placed in a fixed position and coupled to the drum by, for example, a coupling portion for sealing the drum. Then, the radioactive waste is loaded into the drum through an injection tube.

[0003] Medium- and low-level radioactive waste inevitably generated in the nuclear power industry must ensure safety and integrity suitable for regulatory requirements during handling and disposal, except for extremely low-level radioactive substances. As a method for ensuring the safety and integrity of radioactive substances, there are methods of solidifying or packaging them in special containers that already ensure safety and integrity, namely, high-integrity containers (High Integrity Container, HIC).

[0004] Currently, the term "high-integrity container" is not common in most countries except for several countries such as the United States, South Korea, and China. Also, although waste classification and stabilization requirements vary from country to country, it is naturally recognized that a waste container concept that maintains integrity for more than 300 years at a disposal site is necessary.

Summary of the Invention

Problems to be Solved by the Invention

[0005] A high-integrity container is defined as a radioactive waste packaging container that can maintain integrity for more than 300 years under general underground environments and disposal conditions in South Korea. The target waste includes concentrated waste liquid dry powder, dry waste resin, and solidified bodies of concentrated waste liquid and waste resin.

[0006] The problem that this invention aims to solve is to enhance the safety of dried concentrated waste liquid and waste resin loaded into a highly sound container. Specifically, the present invention aims to fix and seal the top of the loaded radioactive waste so that radioactive waste does not leak out to the outside in the event of an accident such as the highly sound container falling or the lid being damaged.

[0007] The problems addressed by the present invention are not limited to those mentioned above, and any other problems not mentioned will be clearly understood by those skilled in the art from the following description. [Means for solving the problem]

[0008] An embodiment of the present invention for achieving the above objectives is for immobilizing the upper part of radioactive waste inside a highly sound container in order to prevent the radioactive waste loaded into the highly sound container from leaking out to the outside, and may include a polymer resin injection unit that injects an immobilization polymer resin onto the radioactive waste loaded into the highly sound container to form a polymer resin layer, a polymer resin sensing unit that measures the layer thickness of the polymer resin layer and adjusts the amount of polymer resin injected, and a photocuring unit that hardens the polymer resin layer.

[0009] The aforementioned polymer resin may contain acrylate oligomers, monomers, and photoinitiators.

[0010] The polymer resin sensing unit measures the lamination thickness of the polymer resin layer multiple times, The amount of polymer resin injected can be adjusted by the average value of these values.

[0011] If the measurement result of the polymer resin sensing unit, or the average value, is not suitable for a preset lamination thickness, the polymer resin injection unit may inject the polymer resin further.

[0012] The photocuring unit can rotate on the polymer resin layer in order to uniformly cure the polymer resin layer.

[0013] The light-curing part can rotate with respect to the center of the highly sound container.

[0014] Another embodiment of the present invention for achieving the above objectives provides a method for immobilizing radioactive waste, which is intended to immobilize the upper part of the radioactive waste inside a highly sound container in order to prevent the radioactive waste contained in the highly sound container from leaking out to the outside. This method may include: a) injecting an immobilization polymer resin onto the radioactive waste contained in the highly sound container to form a polymer resin layer; b) measuring the thickness of the polymer resin layer and adjusting the amount of polymer resin injected; and c) curing the polymer resin layer.

[0015] In step b) above, the amount of polymer resin injected can be adjusted by measuring the lamination thickness of the polymer resin layer multiple times and adjusting the amount of polymer resin injected based on the average value of these measurements.

[0016] If the average value is not suitable for the predetermined lamination thickness, the polymer resin may be further injected.

[0017] The above step c) of curing the polymer resin layer can be repeated.

[0018] Specific details of other embodiments are included in the detailed description and drawings. [Effects of the Invention]

[0019] The present invention provides a radioactive waste immobilization device and an immobilization method using the same, which immobilizes and seals the upper part of the loaded radioactive waste, preventing the radioactive waste from leaking out in the event of an accident such as the dropping of a highly sound container or damage to the lid. [Brief explanation of the drawing]

[0020] [Figure 1] This is a flowchart showing a method for immobilizing radioactive waste according to an embodiment of the present invention. [Figure 2]It is a diagram showing an example of radioactive waste loaded in a highly robust container. [Figure 3] It is a diagram showing that the polymer resin injection part injects polymer resin onto the upper part of the radioactive waste. [Figure 4] It is a diagram showing that the polymer resin sensing part measures the thickness of the polymer resin layer. [Figure 5] It is a diagram showing that the photo-curing part cures the polymer resin layer. [Figure 6] It is a diagram showing a polymer layer for immobilizing radioactive waste formed on the radioactive waste. [Figure 7] It is a diagram showing a plan view of an apparatus for immobilizing radioactive waste according to an embodiment of the present invention.

Best Mode for Carrying Out the Invention

[0021] In order to prevent the radioactive waste loaded in a highly robust container from flowing out to the outside, the present invention provides an apparatus for immobilizing the upper part of the radioactive waste in the highly robust container. The apparatus includes a polymer resin injection part that injects an immobilizing polymer resin onto the radioactive waste loaded in the highly robust container to form a polymer resin layer, a polymer resin sensing part that measures the laminated thickness of the polymer resin layer and adjusts the injection amount of the polymer resin, and a photo-curing part that cures the polymer resin layer.

Mode for Carrying Out the Invention

[0022] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The advantages and features of the present invention, as well as the methods for achieving them, will become clear by referring to the embodiments described in detail hereinafter together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and can be realized in various different forms. These embodiments are merely provided to complete the disclosure of the present invention and to fully inform those with ordinary knowledge in the technical field to which the present invention belongs of the scope of the invention. The present invention is defined only by the scope of the claims. Throughout the specification, the same reference numerals refer to the same components.

[0023] The following describes an embodiment of the present invention concerning a radioactive waste immobilization apparatus and a radioactive waste immobilization method using the same.

[0024] Figure 1 is a flowchart showing a method for immobilizing radioactive waste according to an embodiment of the present invention; Figure 2 is a diagram showing an example of radioactive waste loaded into a highly sound container; Figure 3 is a diagram showing a polymer resin injection unit injecting polymer resin onto the top of the radioactive waste; Figure 4 is a diagram showing a polymer resin sensing unit measuring the thickness of the polymer resin layer; Figure 5 is a diagram showing a photocuring unit curing the polymer resin layer; Figure 6 is a diagram showing a polymer layer for immobilizing radioactive waste formed on the radioactive waste; and Figure 7 is a diagram showing a plan view of a radioactive waste immobilization apparatus according to an embodiment of the present invention.

[0025] Referring to Figure 2, the radioactive waste 12 is loaded into a highly sound container 10 and stored.

[0026] Radioactive waste 12 may be concentrated liquid waste dried powder, dried waste resin, or solidified concentrated liquid waste and waste resin, but there are no restrictions as long as it is waste generated at a nuclear power plant.

[0027] The highly sound container 10 can be defined as a radioactive waste packaging container that can maintain its integrity for more than 300 years under typical underground environmental and disposal conditions in South Korea. The highly sound container 10 can consist of a cylindrical drum and a lid located in the upper central part of the drum to seal it. The upper central part of the drum has an opening formed to allow radioactive waste to be loaded.

[0028] Upon examining the high-sturdiness container 10, it can be found that the outside of the drum may be surrounded by, for example, stainless steel or carbon steel to reinforce the impact strength of the high-sturdiness container 10 against external impacts. In this case, it is preferable to use stainless steel or carbon steel with a thickness of 1 mm to 5 mm. The high-sturdiness container 10 can also be formed from concrete.

[0029] Referring to Figure 7, the radioactive waste immobilization device 100 according to an embodiment of the present invention is for immobilizing the upper part of the radioactive waste 12 inside the highly insulated container 10 in order to prevent the radioactive waste 12 loaded into the highly insulated container 10 from leaking out to the outside.

[0030] The radioactive waste immobilization device 100 according to an embodiment of the present invention may include a main body 101, a polymer resin injection unit 110 attached to the main body 101, a polymer resin sensing unit 120 attached to the main body 101, and a photocuring unit 130 attached to the central part of the main body 101.

[0031] The main unit 101 is placed on the upper part of the highly sound container 10. Once the radioactive waste immobilization process for the radioactive waste 12 is complete, the radioactive waste immobilization device 100 will be separated from the upper part of the highly sound container 10. The radioactive waste immobilization device 100 can then be placed in another highly sound container 100 where the immobilization work is to be carried out.

[0032] The main body 101 may include a polymer resin storage section inside which polymer resin to be injected into the high-soundness container 10 is stored. The main body 101 may also include a control section that controls the polymer resin injection section 110 and the polymer resin sensing section 120.

[0033] The main body 101 can be formed in a circular shape. The shape of the main body 101 is formed in a circular shape so that it can easily overlap with the upper part of the cylindrical high-soundness container 10, but the shape of the main body 101 is not limited to this.

[0034] The polymer resin injection unit 110 is attached to the main body 10. The polymer resin injection unit 110 receives polymer resin from the polymer resin storage unit described above and can inject the polymer resin into the high-storability container 10. For this purpose, the polymer resin injection unit 110 may include a discharge nozzle for discharging the polymer resin into the high-storability container 10. The polymer resin injection unit 110 may be positioned overlapping the upper opening of the high-storability container 10.

[0035] Referring to Figure 3, the polymer resin discharged from the polymer resin injection unit 110 is injected into the upper part of the radioactive waste 12, and after being injected for a certain period of time, the polymer resin is layered to form a polymer resin layer 51. In other words, the polymer resin injection unit 110 can inject an immobilization polymer resin onto the radioactive waste 12 loaded into the highly sound container 10 to form a polymer resin layer 51.

[0036] The polymer resin can be formed from a photocurable resin. The polymer resin may contain acrylate oligomers, monomers, photoinitiators, and other additives that complement its properties. The acrylic oligomer may be selected from urethane, epoxy, ester, ether, or silicone types. Preferably, polyurethane acrylate produced by reacting diisocyanate, polyol, and methacrylate is used.

[0037] More specifically, the essential components of the oligomer can be a mixture of a base material, either a polycarbonate-type urethane acrylate or a polyester-type urethane acrylate, a monomer that is linked by polymer chains to improve adhesion and fixation between the radioactive waste 12, and a photoinitiator that promotes cross-linking of the base material, all in predetermined proportions.

[0038] Of the aforementioned base materials, urethane acrylate is a mixture of urethane (-NHCOO-) and acrylate (-OCOHC=CH2) for moldability and crack prevention. Epoxy acrylates and polyester acrylates can be further added to compensate for the shortcomings of urethane acrylate in terms of heat resistance and adhesion.

[0039] Furthermore, by adjusting the viscosity of the oligomer, the monomer can improve adhesion, spreadability, and polymerization reaction rate on radioactive waste 12, thereby improving workability. It can also play an important role in water resistance, moldability, dimensional stability during thermoforming, heat resistance, tear resistance, thermal shock stability, and high temperature and high humidity stability. Monofunctional acrylate system It may be one of the following: acrylates, difunctional acrylates, trifunctional acrylates, or multifunctional acrylates.

[0040] A photoinitiator can cause the oligomer to initiate a polymerization reaction, forming crosslinks on the radioactive waste 12 and solidifying. To improve the adhesion and fixation of the oligomer, one of the following can be used to promote the UV polymerization reaction: alpha hydroxy ketones, phenyl glyoxylate, or phosphine oxide.

[0041] The polymer resin sensing unit 120 is mounted on the main body 101. The polymer resin sensing unit 120 can measure the thickness of the polymer resin layer 51 and adjust the amount of polymer resin injected. The polymer resin sensing unit 120 can measure the thickness of the polymer resin layer 51 using a laser distance measurement method.

[0042] Referring to Figure 4, the polymer resin sensing unit 120 can measure the lamination thickness of multiple polymer resin layers 51 and adjust the amount of polymer resin injected based on the average value of these measurements. Specifically, the polymer resin sensing unit 120 measures the thickness of various parts of the polymer resin layer 51 to obtain thickness values, and then determines the thickness of the formed polymer resin layer 51 based on the average of the obtained thickness values.

[0043] If the average thickness measured by the polymer resin sensing unit 120 does not match the preset layer thickness, it is necessary to form a thicker polymer resin layer 51. In this case, the control unit of the main body 101 starts operating the polymer resin injection unit 110. This allows the polymer resin injection unit 110 to inject more polymer resin into the high-soundness container 10. Subsequently, the polymer resin sensing unit 120 measures the thickness of the polymer resin layer 51, and if the formed thickness of the polymer resin layer 51 matches the preset thickness, no further polymer resin is injected.

[0044] In other words, when the polymer resin is injected into the highly sound container 10 by the polymer resin injection unit 110 to form a polymer resin layer 51, the polymer resin sensing unit 120 measures the thickness of the polymer resin layer 51. If the thickness of the polymer resin layer does not meet the set value, more polymer resin is injected. If the thickness of the polymer resin layer meets the set value, the injection of polymer resin is stopped and the formed polymer resin layer is cured.

[0045] The photocuring unit 130 is attached to the main body 101. The photocuring unit 130 cures the polymer resin layer 51.

[0046] Referring to Figure 5, the photocuring section 130 may include a UV irradiation section 131 and a rotating shaft 132. The UV irradiation section 131 is connected to one end of the rotating shaft 132, and the other end of the rotating shaft 132 is connected to the main body 101. In this case, the main body 101 may include a drive unit that rotates the rotating shaft 132.

[0047] Furthermore, the photocuring unit 130 can rotate on the polymer resin layer 51 in order to uniformly cure the polymer resin layer 51. That is, when the rotation axis 132 of the photocuring unit 130 rotates, the UV irradiation unit 131 connected to one end of the rotation axis 132 can also rotate. The polymer resin layer 51 can be uniformly cured by the rotation of the UV irradiation unit 131. At this time, rotation The axis 132 rotates with respect to the center of the high-storability container 10. Therefore, the UV irradiation unit 131 also rotates with respect to the center of the high-storability container 10. In other words, the photocuring unit 130 as a whole can rotate with respect to the center of the high-storability container.

[0048] Specifically, when UV light is irradiated onto the polymer resin layer 51 by the UV irradiation section 131 of the photocuring section 130, and the photoinitiator starts polymerization or polymerization reaction, the polymer resin layer 51 hardens uniformly and evenly due to the UV curing mechanism.

[0049] In other words, the polymer resin layer 51 is UV cured to solidify by forming cross links through a free radical polymerization UV curing mechanism. Here, the UV irradiation unit 131 may be one of a metal lamp, a mercury lamp, or an LED lamp.

[0050] The photocuring process can be repeated several times to fix the polymer resin layer 51.

[0051] Next, with reference to Figures 1 to 6, a method for immobilizing radioactive waste according to an embodiment of the present invention will be described. The method for immobilizing radioactive waste according to the present invention is for immobilizing the upper part of the radioactive waste inside a highly sound container in order to prevent the radioactive waste loaded into the highly sound container from leaking out to the outside.

[0052] Referring to Figures 1 and 3, a polymer resin for immobilization is injected onto the radioactive waste 12 loaded into the highly sound container 10 to form a polymer resin layer 51 (S10). The polymer resin is injected via the polymer resin injection section 110 described above. Since the polymer resin layer is substantially the same as the polymer resin described above, redundant explanations are omitted.

[0053] Referring further to Figures 1 and 4, the thickness of the polymer resin layer 51 can be measured and the amount of polymer resin injected can be adjusted (S20). The thickness of the polymer resin layer 51 is adjusted by the polymer resin sensing unit 120 described above.

[0054] Adjusting the amount of polymer resin injected in step S20 allows for measuring the lamination thickness of the polymer resin layer 51 multiple times and adjusting the amount of polymer resin injected based on the average value of these measurements. More specifically, if the average value is not suitable for the preset lamination thickness, the polymer resin can be injected further. Conversely, if the average value is suitable for the preset lamination thickness, the additional injection of polymer resin can be interrupted.

[0055] Referring to Figures 1 and 5, the step of curing the polymer resin layer 51 is performed (S30). The S30 step of curing the polymer resin layer 51 can be repeated. This step allows the polymer resin layer formed by the injection of polymer resin to be fixed. This completes the formation of the polymer resin layer 51 that fixes the radioactive waste 12 (see Figure 6). With the formation of the polymer resin layer 51, the upper part of the radioactive waste 12 can be sealed from the outside within the highly sound container 10.

[0056] According to the present invention, the upper part of the radioactive waste 12 loaded into the highly sound container 10 can be fixed with a polymer resin. This enhances and improves the storage safety of the radioactive waste. In particular, it prevents the radioactive waste from leaking out in the event of an accident such as the highly sound container falling or the lid being damaged.

[0057] Embodiments of the present invention have been described above with reference to the attached drawings, but the present invention belongs to Those with ordinary skill in the art will understand that the present invention can be implemented in other specific forms without altering its technical idea or essential features. Therefore, it should be understood that the above embodiment is illustrative in all respects and not limiting.

Claims

1. In order to prevent the possibility of radioactive waste loaded into a highly sound container leaking to the outside, a device for fixing the upper part of the radioactive waste inside the highly sound container is provided. A polymer resin injection unit for injecting a polymer resin for immobilization onto the radioactive waste placed in the aforementioned highly sound container to form a polymer resin layer, A polymer resin sensing unit measures the thickness of the polymer resin layer and adjusts the amount of polymer resin injected; It includes a photocuring part for curing the polymer resin layer, The aforementioned polymer resin comprises an acrylate oligomer, a monomer, and a photoinitiator. The polymer resin sensing unit measures the lamination thickness of the polymer resin layer multiple times, A radioactive waste immobilization device characterized by adjusting the injection amount of the polymer resin based on these average values.

2. If the measurement result of the polymer resin sensing unit, the average value, is not suitable for a preset lamination thickness, The radioactive waste immobilization apparatus according to claim 1, characterized in that the polymer resin injection section further injects the polymer resin.

3. The radioactive waste immobilization apparatus according to claim 1, characterized in that the photocuring unit rotates on the polymer resin layer in order to uniformly cure the polymer resin layer.

4. The radioactive waste immobilization apparatus according to claim 3, characterized in that the photocuring part rotates with respect to the center of the highly sound container.

5. In order to prevent the possibility of radioactive waste contained in a highly sound container leaking to the outside, a method for fixing the upper part of the radioactive waste inside the highly sound container, a) A step of injecting a polymer resin for immobilization onto the radioactive waste placed in the high-storability container to form a polymer resin layer, b) A step of measuring the lamination thickness of the polymer resin layer and adjusting the amount of polymer resin injected, c) The process includes the step of curing the polymer resin layer, The aforementioned polymer resin comprises an acrylate oligomer, a monomer, and a photoinitiator, and is a method for immobilizing radioactive waste.

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