Liquid radioactive waste treatment system

Abstract

To enable appropriate shielding around a liquid radioactive waste treatment system for treating liquid radioactive waste containing α-nuclides.SOLUTION: A liquid radioactive waste treatment system for treating liquid radioactive waste containing α-nuclides is provided, the system comprising a container for storing a solid component, liquid component, or slurry containing α-nuclides, piping for allowing the solid component, liquid component, or slurry containing α-nuclides to flow therethrough, and a shield body partially or fully surrounding the container and the piping.SELECTED DRAWING: Figure 2A

Description

[Technical field]

[0001] The present disclosure relates to a radioactive liquid waste treatment system. [Background technology]

[0002] As disclosed in Non-Patent Document 1, technological development is underway to remove fuel debris.

[0003] Patent Document 1 discloses a technology in an alpha nuclide removal system that treats radioactive liquid waste containing alpha nuclides, in which a de-carbonation agent is injected to adjust the water quality of the radioactive liquid waste containing alpha nuclides, and then an adsorbent is used to adsorb and remove the alpha nuclides.

[0004] Patent Document 2 discloses a method for treating radioactive waste liquid containing radioactive cesium and radioactive strontium by forming an adsorbent containing crystalline silicotitanate and titanate into a predetermined particle size, filling the adsorption tower with a predetermined bed height, and passing the radioactive waste liquid through the tower. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 7273682 [Patent Document 2] JP 2017-106817 A Adsorbent Adsorbent [Non-patent literature]

[0006] [Non-Patent Document 1] International Research Institute for Nuclear Decommissioning (IRID) public documents: https: / / irid.or.jp / wp-content / uploads / 2022 / 09 / 2021011anzensystem.pdf Summary of the Invention [Problem to be solved by the invention]

[0007] Non-Patent Document 1 states that the use of RO membranes in removing fuel debris is also being considered. However, when using RO membranes, the RO membranes themselves and equipment for treating concentrated water are required. In that case, there is a problem that the scale of the equipment becomes large. In addition, remote operation is difficult for replacing the RO membranes, and manned work is expected to be required, which increases the work exposure. For this reason, if possible, a system that does not use RO membranes is desirable.

[0008] The radioactive waste liquid generated during the fuel debris removal work contains alpha nuclides, so operations such as those for treating the radioactive waste liquid must be carried out remotely as much as possible, but it is thought that some work will still need to be carried out by workers in close proximity.

[0009] Patent Documents 1 and 2 contain no description regarding shielding of components of the radioactive waste liquid treatment system.

[0010] An object of the present disclosure is to provide appropriate shielding around components of a radioactive waste liquid treatment system that treats radioactive liquid waste containing alpha nuclides. [Means for solving the problem]

[0011] The radioactive waste liquid treatment system of the present disclosure is a system for treating radioactive waste liquid containing alpha nuclides, and is equipped with a container for storing a solid component, liquid component or slurry containing alpha nuclides, piping through which the solid component, liquid component or slurry containing alpha nuclides flows, and a shielding body, and the shielding body is arranged around part or all of the container and the piping. Effect of the Invention

[0012] According to the present disclosure, it is possible to appropriately shield the surroundings of components of a radioactive liquid waste treatment system that treats radioactive liquid waste containing alpha nuclides. [Brief description of the drawings]

[0013] [Figure 1]1 is a flow chart showing the main steps of the radioactive liquid waste treatment process of Example 1. [Figure 2A] 1 is a schematic configuration diagram showing an example of a radioactive waste liquid treatment system according to a first embodiment. [Figure 2B] FIG. 2 is a schematic diagram showing a configuration for shielding a tank that stores radioactive liquid waste, which is an example of a component of the radioactive liquid waste treatment system of the first embodiment. [Figure 2C] FIG. 2C is a perspective view of the tank of FIG. 2B. [Figure 2D] FIG. 2C is a perspective view showing a modification of the tank of FIG. 2B. [Diagram 3] FIG. 11 is a schematic diagram showing an example of a radioactive waste liquid treatment system according to a second embodiment. [Figure 4] FIG. 11 is a schematic diagram showing an example of a radioactive waste liquid treatment system according to a third embodiment. [Diagram 5] FIG. 11 is a schematic diagram showing an example of a radioactive waste liquid treatment system according to a fourth embodiment. [Figure 6] FIG. 11 is a schematic diagram showing an example of a radioactive waste liquid treatment system according to a fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, examples of the present disclosure will be described with reference to the drawings. Note that the structures, materials, and other specific configurations shown in the present disclosure are not limited to the examples described here, and can be appropriately combined, modified, substituted, etc., without departing from the spirit and scope of the present disclosure. EXAMPLES

[0015] Example 1 is a radioactive waste treatment process that is applied to treat radioactive liquid waste that contains alpha nuclides in various states such as ions, colloids, and fine particles, which are generated during fuel debris retrieval.

[0016] When fuel debris is removed from the Fukushima Daiichi Nuclear Power Plant, it is excavated. Since the fuel debris contains alpha nuclides, the alpha nuclides are mixed into the contaminated water inside the reactor containment vessel during excavation. As a result, the radioactive waste liquid generated during the fuel debris removal work contains alpha nuclides.

[0017] FIG. 1 is a flow chart showing the main steps of the radioactive liquid waste treatment process of this embodiment.

[0018] As shown in the figure, a pretreatment process S1 is carried out on the radioactive liquid waste generated during the fuel debris removal work.

[0019] In the pretreatment step S1, the pH and redox potential of the radioactive waste liquid are adjusted to make the alpha nuclides into a chemical form that is easily adsorbed in the alpha nuclide removal device. To adjust the pH, hydrochloric acid, sulfuric acid, nitric acid, etc. are injected to make the liquid acidic, and sodium hydroxide, etc. are injected to make the liquid alkaline. To adjust the redox potential, an organic acid such as formic acid, oxalic acid, acetic acid, citric acid, etc. or a salt of the organic acid is injected as an oxidizing agent, and hydrazine, etc. is injected as a reducing agent. If necessary, a flocculant is injected into the radioactive waste liquid to flocculate and precipitate colloids (colloid particles) and fine particles in the radioactive waste liquid. In this specification, liquid colloid (colloid solution) is considered to be a type of liquid component.

[0020] The radioactive liquid waste, the quality of which has been adjusted in the pretreatment step S1, is subjected to the alpha nuclide adsorption step S2 in which the alpha nuclide is removed by adsorption.

[0021] In the α-nuclide adsorption step S2, ferrite (Fe3O4) which is an α-nuclide adsorbent is supplied to the radioactive liquid waste containing α-nuclides. The α-nuclides are adsorbed by the ferrite and removed from the radioactive liquid waste. The α-nuclide removal device may be a batch type device which supplies a powdered α-nuclide adsorbent to the radioactive liquid waste stored in a container, or a column type device which causes the radioactive liquid waste to flow through an adsorption tower filled with the α-nuclide adsorbent. The α-nuclide removal device may be a combination of the batch type and the column type.

[0022] Regardless of whether the equipment is a batch type or a column type, it is necessary to place a shield around the equipment. This is because workers need to approach the equipment as necessary. In other words, it is necessary to place a shield around the equipment where liquids or adsorbents containing radioactive materials are retained or circulated, and to configure it so that workers can replace it. This makes it possible to reduce the radiation dose that workers are exposed to when replacing the shield.

[0023] When a powder of sodium crystalline silicotitanate (CST-Na) is supplied as an alpha nuclide adsorbent, the addition of the adsorbent causes alkaline substances (Na ions, etc.) to elute from the adsorbent, and the pH of the target to be treated rises, making it easier for the alpha nuclides to precipitate, and the growth of colloids or precipitation on the surface of the adsorbent makes it easier to remove the alpha nuclides. In this case, the pretreatment step S1 and the alpha nuclide adsorption step S2 may be performed simultaneously.

[0024] In the above examples, ferrite or sodium-type crystalline silicotitanate (CST-Na) is given as the α nuclide adsorbent, but the α nuclide adsorbent according to the present disclosure is not limited thereto, and may be one having impregnated activated carbon (e.g., oxine-impregnated activated carbon), or activated carbon, titanate, iron oxide other than ferrite, etc. as the main component or base material.

[0025] In the adsorbent separation step S3 following the α nuclide adsorption step S2, the adsorbent is separated from the radioactive liquid waste. Note that an ultrafiltration membrane (UF membrane) or the like may be used for the separation.

[0026] The treated water separated from the adsorbent in the adsorbent separation process S3 is stored in a receiving tank (storage process S4). The treated water in the receiving tank is transferred to an existing water treatment facility and treated. The treated water in the receiving tank may also be returned to the reactor containment vessel and used for predetermined treatment in the reactor containment vessel.

[0027] Next, an example of a radioactive liquid waste treatment system used for treating radioactive liquid waste including each process from steps S1 to S4 of the first embodiment will be described.

[0028] FIG. 2A is a schematic diagram showing an example of the radioactive liquid waste treatment system of this embodiment.

[0029] The radioactive liquid waste treatment system shown in this figure comprises an alpha nuclide removal section 1 that removes alpha nuclides from radioactive liquid waste containing alpha nuclides, and a waste liquid treatment section 2 that treats the waste liquid flowing out from the alpha nuclide removal section 1.

[0030] The α nuclide removal section 1 includes a water quality adjustment facility 3 and an α nuclide removal device 4.

[0031] The water quality conditioning facility 3 performs the pretreatment step S1 in FIG.

[0032] The α nuclide removal device 4 has a radioactive liquid waste receiving tank 7 and an adsorbent supplying device 8.

[0033] From the adsorbent supply device 8, an adsorbent (such as ferrite) that adsorbs alpha nuclides is supplied to the radioactive liquid waste receiving tank 7 through a connection part 13.

[0034] The water quality conditioning equipment 3 and the radioactive liquid waste receiving tank 7 of the alpha nuclide removal device 4 are connected by a liquid waste transfer equipment 10.

[0035] The waste liquid treatment unit 2 includes an adsorbent separation device 5 and a treated water receiving tank 6. The adsorbent separation device 5 and the treated water receiving tank 6 are connected by a treated water transfer facility 12.

[0036] The radioactive liquid waste receiving tank 7 of the α nuclide removal section 1 and the waste liquid treatment section 2 are connected by an α nuclide removed liquid transfer facility 11 .

[0037] In this way, the radioactive waste liquid treatment system (alpha nuclide removal system) shown in this diagram connects the water quality adjustment equipment 3, the radioactive waste liquid receiving tank 7, the adsorbent separation device 5, and the treated water receiving tank 6 in series, through which the radioactive waste liquid is passed and treated.

[0038] In addition, in the α-nuclide removal device 4 and the waste liquid treatment unit 2, a configuration in which one radioactive waste liquid receiving tank 7 and one treated water receiving tank 6 are provided respectively is shown, but the number of these tanks is not particularly limited, and multiple tanks may be provided. Furthermore, the tanks are not limited to those used for treatment or storage, and may be buffer tanks having a function of adjusting the flow rate of waste liquid according to the treatment capacity downstream.

[0039] Pumps (not shown) are provided as necessary in the waste liquid transfer equipment 10, the α-nuclide removed liquid transfer equipment 11, the treated water transfer equipment 12 and the connection part 13. The pumps are configured so that their operation is controlled by a control part provided near the pumps or in a control room in a separate building. This configuration enables the transfer of waste liquid and adsorbents.

[0040] The adsorbent supplying device 8 stores an adsorbent that selectively adsorbs α-nuclides. The adsorbent is supplied to the radioactive liquid waste receiving tank 7 through a connection part 13. The adsorbent comes into contact with the radioactive liquid waste containing α-nuclides that is transferred to the radioactive liquid waste receiving tank 7 through the liquid waste transferring equipment 10, and selectively adsorbs the α-nuclides from the radioactive liquid waste.

[0041] A part or the whole of the adsorbent in the radioactive liquid waste receiving tank 7 is transferred to the adsorbent separation device 5 via α-nuclide-removed liquid transfer equipment 11 together with the waste liquid from which the α-nuclides have been removed.

[0042] In the adsorbent separation device 5, only the adsorbent is separated from the waste liquid containing the used adsorbent.

[0043] The waste liquid after separation from the adsorbent is stored in a treated water receiving tank 6, and then transferred to an existing water treatment facility for treatment. The treated water in the receiving tank may be returned to the reactor containment vessel and used for predetermined treatment in the reactor containment vessel.

[0044] Next, a configuration for shielding one of the components of the radioactive liquid waste treatment system of this embodiment will be described.

[0045] FIG. 2B is a schematic diagram showing a configuration for shielding a tank that stores radioactive liquid waste, which is an example of a component of the radioactive liquid waste treatment system of this embodiment.

[0046] In this figure, a configuration is shown in which the periphery of a tank 201 is covered with a shielding body 210. A pipe 202 for introducing waste liquid and the like and a pipe 203 for discharging treated liquid are connected to the tank 201. The shielding body 210 is made of concrete (preferably containing lead), a lead alloy, or the like. Considering the required thickness of the shielding body 210, it is preferable to form the shielding body 210 from a lead alloy.

[0047] The height of the shield 210 is greater than that of the tank 201 .

[0048] If the shield 210 is made of a lead alloy, the thickness of the shield 210 can be made relatively small, so that a small crane can be used when replacing the tank 201. In addition, it is also suitable for a case where an operator performs manual work near the tank 201, or a case where a manually operated machine is used. The crane may be of any type, such as a ceiling-mounted type or a mobile type having legs. In addition, it is preferable to remotely operate the crane for operations such as replacing the tank 201. However, depending on the work content, it is necessary for the operator to approach the tank 201. Even in such a case, since the shield 210 has a sufficient height, the operator can approach the tank 201, although only for a short time, and the radiation exposure dose of the operator can be suppressed.

[0049] FIG. 2C is a perspective view of the tank of FIG. 2B.

[0050] In FIG. 2C, the upper surface of the tank 201 is also covered with the shield 210. The shield 210 on the upper surface of the tank 201 is desirably a lid-like one that can be separated from the side portion. In other words, the shield 210 has a removable lid that covers the upper surface portion of the tank 201. In addition, the tank 201 desirably has a removable configuration. This makes it possible to remove the lid portion of the shield 210 as necessary, to remove liquid, slurry, etc. inside the tank 201, and to remove the tank 201 itself, etc. This makes it possible to reduce the amount of radiation emitted upward from the tank 201 that leaks into the surroundings.

[0051] FIG. 2D is a perspective view showing a variation of the tank of FIG. 2B.

[0052] 2D, the top surface of tank 201 is open and not covered by shield 210a. With this configuration, when removing liquid, slurry, etc. from tank 201 or removing tank 201 itself, it is not necessary to remove the lid of shield 210a, and the removal operation can be easily performed.

[0053] Although the above shielding configuration has been described using a tank for storing radioactive waste liquid as an example, the shielding configuration is not limited to the above example and includes a configuration for shielding a column-shaped adsorption tower filled with an adsorbent, etc. In other words, the radioactive waste liquid treatment system of the present disclosure includes a configuration in which the tank 201 shown in Figures 2B to 2D is replaced with an adsorption tower, etc.

[0054] In the above example, the tank 201, which is a single container, is individually covered with the shields 210, 210a, but the radioactive liquid waste treatment system according to the present disclosure is not limited to such an individual shielding configuration, and may be configured to cover a series of containers and piping, as well as the equipment required therefor, in whole or in part with the shield. In that case, the shield may be installed only on the side of the object to be shielded, or the shield may also be installed on the top surface of the object. It is desirable that the shield installed on the top surface be a lid that is entirely or partially removable. EXAMPLES

[0055] Next, a description will be given of Example 2. Note that in this example, detailed descriptions of processes and configurations similar to those in Example 1 will be omitted.

[0056] In the second embodiment, steps S1 to S4 shown in FIG. 1 of the first embodiment are also carried out.

[0057] In the pretreatment step S1 of the second embodiment, a flocculant such as aluminum sulfate or polyaluminum chloride is supplied to the radioactive liquid waste containing alpha nuclides. The flocculant can cause the colloids and fine particles in the radioactive liquid waste to flocculate and settle.

[0058] In the α-nuclide adsorption step S2, ferrite, which is an α-nuclide adsorbent, is supplied to the supernatant liquid that has been subjected to the coagulation and sedimentation treatment in the pretreatment step S1, and the α-nuclide is adsorbed and removed from the radioactive liquid waste in the same manner as in Example 1.

[0059] FIG. 3 is a schematic diagram showing an example of a radioactive waste liquid treatment system according to the second embodiment.

[0060] In the radioactive liquid waste treatment system shown in this figure, a flocculant injector 14 is provided in place of the water quality adjustment equipment 3 in Figure 2A. The flocculant injector 14 has a radioactive liquid waste receiving tank 18 and a flocculant supplying device 16.

[0061] A flocculant (aluminum sulfate or polyaluminum chloride) is supplied from the flocculant supplying device 16 to a radioactive liquid waste receiving tank 18 through an injection pipe 17. The radioactive liquid waste receiving tank 18 of the flocculant injecting device 14 and the radioactive liquid waste receiving tank 7 of the alpha nuclide removal device 4 are connected by a supernatant liquid transferring facility 15.

[0062] The α nuclide removal device 4 and subsequent components have the same configuration as in the first embodiment. EXAMPLES

[0063] Next, a description will be given of Example 3. Note that in this example, detailed descriptions of processes and configurations similar to those in Example 1 will be omitted.

[0064] In the third embodiment, steps S1 to S4 shown in FIG. 1 of the first embodiment are also carried out.

[0065] In the pretreatment step S1 of the third embodiment, a solution of an organic acid such as formic acid, oxalic acid, acetic acid, or citric acid is supplied to the radioactive liquid waste containing alpha nuclides, thereby dissolving colloids and fine particles in the liquid waste.

[0066] Organic acids may combine with ionic radionuclides to form complexes that cannot be adsorbed by the adsorbent. Therefore, after dissolving colloids and fine particles with an organic acid solution, an oxidizing agent such as hydrogen peroxide or ozone that decomposes organic acids is injected into the radioactive waste liquid to change the complexed radionuclides into ionic states that can be adsorbed by the adsorbent. This pretreatment step S1 allows the process to proceed to the α-nuclide adsorption step S2, which is the same as in Example 1.

[0067] FIG. 4 is a schematic diagram showing an example of a radioactive liquid waste treatment system according to the third embodiment.

[0068] In the radioactive liquid waste treatment system shown in this figure, a chemical injection device 19 is provided in place of the water quality adjustment equipment 3 in Figure 2A. The chemical injection device 19 has an organic acid supply device 21, an oxidizing agent supply device 25, and a radioactive liquid waste receiving tank 23.

[0069] The radioactive liquid waste receiving tank 23 of the chemical injection device 19 and the radioactive liquid waste receiving tank 7 of the alpha nuclide removal device 4 are connected by a supernatant liquid transfer facility 24 .

[0070] From the organic acid supplying device 21, an organic acid such as formic acid, oxalic acid, acetic acid, or citric acid is supplied to a radioactive liquid waste receiving tank 23 through an injection pipe 22.

[0071] Also, an oxidizing agent such as hydrogen peroxide or ozone is supplied from an oxidizing agent supplying device 25 through the injection piping 20 to the radioactive liquid waste receiving tank 23 .

[0072] The α nuclide removal device 4 and subsequent components have the same configuration as in the first embodiment. EXAMPLES

[0073] Next, a description will be given of Example 4. Note that in this example, detailed descriptions of processes and configurations similar to those in Example 1 will be omitted.

[0074] In the fourth embodiment, steps S1 to S4 shown in FIG. 1 of the first embodiment are also carried out.

[0075] In the pretreatment step S1 of the fourth embodiment, a filter is used to remove solid and colloidal radioactive nuclides, and an adsorbent is used to selectively adsorb ions of β and γ nuclides to reduce worker exposure. In the α nuclide adsorption step S2, the same coagulation and sedimentation treatment as in the second embodiment is used to remove colloids and fine particles in the radioactive waste liquid that could not be completely removed by the filter in the previous stage.

[0076] FIG. 5 is a schematic diagram showing an example of a radioactive waste liquid treatment system according to the fourth embodiment.

[0077] In the radioactive waste liquid treatment system shown in this figure, a radioactive nuclide removal device 33 is provided instead of the water quality conditioning equipment 3 in FIG. 2A. The radioactive nuclide removal device 33 has a filter 27 that removes radioactive nuclides including solid and colloidal α nuclides, and an adsorption equipment 28 that incorporates an adsorbent that selectively adsorbs ions of β and γ nuclides. Examples of adsorbents that selectively adsorb ions of β and γ nuclides include silver zeolite and titanate compounds. The filter 27 is incorporated in a specified container.

[0078] The filter 27 and the adsorption equipment 28 are connected by a waste liquid transfer pipe 30. In addition, the adsorption equipment 28 of the radioactive nuclide removal equipment 33 and the radioactive waste liquid receiving tank 7 of the α-nuclide removal equipment 4 are connected by a waste liquid transfer equipment 31.

[0079] Unlike the embodiment 2 (FIG. 3), the α-nuclide removal device 4 is connected to the same radioactive liquid waste receiving tank 7 with a flocculant supplying device 16 and an adsorbent supplying device 8. With this configuration, the overall equipment scale can be reduced.

[0080] The flocculant supplying device 16 supplies a flocculant to the radioactive liquid waste receiving tank 7 through the injection piping 32. The adsorbent supplying device 8 supplies an adsorbent to the radioactive liquid waste receiving tank 7 through the connection part 13.

[0081] By using the filter 27, solid components contained in the radioactive waste liquid can be removed on the upstream side, the amount of sludge to be collected can be reduced, and the downstream configuration can be made more compact.

[0082] In addition, since the adsorption equipment 28 can selectively remove β and γ nuclides, only α nuclides need to be removed downstream. This allows the α nuclides to be recovered separately from the β and γ nuclides. This reduces the amount of radiation generated from the adsorbent that has adsorbed the α nuclides.

[0083] The process flow in the α-nuclide removal device 4 is as follows.

[0084] First, a flocculant containing aluminum sulfate or polyaluminum chloride is supplied from the flocculant supply device 16. This causes colloids and fine particles in the radioactive liquid waste that have not been collected by the filter 27 to be flocculated and precipitated in the radioactive liquid waste receiving tank 7.

[0085] After the coagulation and sedimentation treatment, an α nuclide adsorbent is supplied from an adsorbent supplying device 8 to the radioactive liquid waste receiving tank 7, and the ionic α nuclide in the supernatant liquid is adsorbed and removed.

[0086] The precipitate formed by flocculation in the radioactive liquid waste receiving tank 7 and the slurry containing the α-nuclide adsorbent are transferred to the liquid waste treatment unit 2 through α-nuclide removed liquid transfer equipment 11 .

[0087] Moreover, in the waste liquid treatment section 2, a slurry recovery device 29 is provided in place of the adsorbent separation device 5 in FIG. 2A.

[0088] The slurry recovery device 29 has a filtration section, and recovers solid components from the slurry transferred from the α-nuclide removal device 4. The slurry recovery device 29 and the treated water receiving tank 6 are connected by a treated water transfer piping . EXAMPLES

[0089] Next, a description will be given of Example 5. Note that in this example, detailed descriptions of processes and configurations similar to those in Example 4 will be omitted.

[0090] In the fifth embodiment, steps S1 to S4 shown in FIG. 1 of the first embodiment are also carried out.

[0091] FIG. 6 is a schematic diagram showing an example of a radioactive waste liquid treatment system according to the fifth embodiment.

[0092] In the radioactive waste liquid treatment system shown in this figure, the configuration of the α nuclide removal section 1 is the same as that in FIG.

[0093] In Fig. 6, the slurry recovery device 29 and the treated water receiving tank 6 are connected by a treated water transfer facility 12. A branch is provided midway through the treated water transfer facility 12, and treated water transfer piping 34 connected to the radioactive liquid waste receiving tank 7 of the alpha nuclide removal section 1 is added from this branch. The treated water transfer piping 34 is used to return the treated water to the radioactive liquid waste receiving tank 7.

[0094] In this embodiment, a flocculant is first injected from the flocculant supplying device 16 into the waste liquid transferred to the radioactive waste liquid receiving tank 7 by the waste liquid transfer equipment 31 to generate a slurry, and the waste liquid is transferred to the slurry recovery device 29 to recover the solid components. Thereafter, the treated water is returned to the radioactive waste liquid receiving tank 7 through the treated water transfer piping 34, and an adsorbent is supplied from the adsorbent supplying device 8 to the radioactive waste liquid receiving tank 7 to remove alpha nuclides.

[0095] This two-stage treatment allows the separation of solid components derived from colloids and fine particles from those derived from the adsorbent, facilitating the treatment of the secondary waste generated and reducing the amount of radioactive waste.

[0096] In this specification, the solid component includes an adsorbent or a precipitate containing the alpha nuclide, the liquid component includes an ion or a colloid of the alpha nuclide, and the slurry is a mixture of a solid component and a liquid component. [Explanation of symbols]

[0097] 1: alpha nuclide removal section, 2: waste liquid treatment section, 3: water quality adjustment equipment, 4: alpha nuclide removal device, 5: adsorbent separation device, 6: treated water receiving tank, 7: radioactive waste liquid receiving tank, 8: adsorbent supply device, 10: waste liquid transfer equipment, 11: alpha nuclide removed liquid transfer equipment, 12: treated water transfer equipment, 13: connection section, 14: flocculant injection device, 15: supernatant liquid transfer equipment, 16: flocculant supply device, 17, 20, 22, 32: injection piping, 1 8: radioactive liquid waste receiving tank, 19: chemical injection equipment, 21: organic acid supply equipment, 23: radioactive liquid waste receiving tank, 24: supernatant liquid transfer equipment, 25: oxidant supply equipment, 27: filter, 28: adsorption equipment, 29: slurry recovery equipment, 30: waste liquid transfer piping, 31: waste liquid transfer equipment, 33: radioactive nuclide removal equipment, 34: treated water transfer piping, 201: tank, 202, 203: piping, 210, 210a: shielding.

Claims

1. A system for treating radioactive liquid waste containing alpha nuclides, comprising: A container for storing a solid component, a liquid component, or a slurry containing the α nuclide; A pipe through which the solid component, the liquid component, or the slurry containing the α nuclide flows; A shield; A radioactive waste liquid treatment system, wherein the shielding is disposed around the container and part or all of the piping.

2. The radioactive liquid waste treatment system according to claim 1 , wherein the shielding body is configured to cover the container and the piping individually.

3. The container is arranged in plurality, 2. The radioactive liquid waste treatment system according to claim 1, wherein the shielding body is configured to cover all or part of the plurality of containers and the piping as a series.

4. The solid component includes an adsorbent or a precipitate containing the alpha nuclide, The radioactive liquid waste treatment system according to claim 1 , wherein the liquid component contains ions or colloids of the alpha nuclide.

5. 2. The radioactive liquid waste treatment system according to claim 1, wherein the container is configured to remove the alpha nuclides using at least one of an adsorbent and a flocculant.

6. The container has a configuration for removing the α nuclides using an adsorbent, The radioactive liquid waste treatment system according to claim 1 , wherein the adsorbent is used in a batch or column configuration.

7. The radioactive liquid waste treatment system according to claim 1 , wherein the container has a detachable structure.

8. 2. The radioactive liquid waste treatment system according to claim 1, wherein the shield is formed of a lead alloy.

9. The radioactive liquid waste treatment system according to claim 1 , wherein the shield covers at least side portions of the container and the piping.

10. The radioactive liquid waste treatment system according to claim 1 , wherein the shield covers an upper surface of the container and the piping.

11. 2. The radioactive liquid waste treatment system according to claim 1, wherein the shielding body has a removable lid for covering an upper surface of the container and the piping.

12. The radioactive liquid waste treatment system according to claim 1 , wherein the alpha nuclide is derived from fuel debris.

13. The container is arranged in plurality, One of the plurality of containers has a configuration for removing β nuclides and γ nuclides using an adsorbent, The radioactive liquid waste treatment system according to claim 1 , wherein the adsorbent is used in a batch or column configuration.

14. The container is arranged in plurality, one of the plurality of containers has a filter for removing the alpha radionuclides, including solid and colloidal ones, from the radioactive liquid waste; 2. The radioactive liquid waste treatment system according to claim 1, wherein another of the plurality of containers is an adsorption facility incorporating an adsorbent that selectively adsorbs ions of beta and gamma nuclides.

15. The container is arranged in plurality, One of the plurality of containers is an organic acid supplying device that supplies an organic acid to the radioactive liquid waste, 2. The radioactive liquid waste treatment system according to claim 1, wherein another of the plurality of containers is an oxidizer supply device that supplies an oxidizer to the radioactive liquid waste.

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