Radioactive material separation and recovery device and separation and recovery method

Abstract

To provide a system and a method for separating and recovering a radioactive material which can efficiently separate and recover a radioactive material.SOLUTION: A system and a method for separating and recovering a radioactive material comprises: a target heating section that heats a target housed inside to vaporize a radioactive material; a radioactive material recovery section that is disposed above the target heating section and cools and recovers the radioactive material vaporized in the target heating section; a piping section that communicates between the target heating section and the radioactive material recovery section; a heating device disposed along a length direction of the piping section; a radiation detector for detecting adhesion of the radioactive material; and a heating control device that drives the heating device based on a detection signal from the radiation detector.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] An embodiment of the present invention relates to an apparatus and a method for separating and recovering radioactive materials. [Background technology]

[0002] In recent years, cancer treatment using alpha rays has been attracting attention. Because alpha rays have a short range, they can be used to selectively attack targeted cancer cells using drugs that emit alpha rays. This has the advantage of causing minimal damage to normal cells.

[0003] Various radioisotopes are being considered as alpha-particle-emitting agents. Astatine-211, in particular, is one of the most promising radioisotopes because it has a short half-life and decays rapidly into stable nuclides. However, because its half-life is only 7.2 hours, the amount of astatine-211 produced decreases if separation is performed too slowly. Therefore, a rapid separation method is needed.

[0004] A rapid and simple separation method is known to utilize the difference in melting and boiling points between astatine-211 and bismuth, the target material. However, with this conventional separation technique, astatine-211 adheres to the walls of the pipes in the collection or transport sections, making it necessary to elute or collect the adhered astatine-211 using an organic solvent or alkaline solution.

[0005] Therefore, the inventors have developed a new separation and recovery technology using aerosols, which reduces the amount of astatine-211 adhering to the walls of pipes and other structures, enabling efficient separation and recovery. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2015 / 195042 [Patent Document 2] International Publication No. 2019 / 088113 [Patent Document 3] International Publication No. 2019 / 112034 [Non-patent literature]

[0007] [Non-Patent Document 1] E. Aneheim, “Automated astatination of biomolecules-a stepping stone towards multicenter clinical trials,” Science Reports, 2015. Summary of the Invention [Problem to be solved by the invention]

[0008] As described above, the present inventors have developed a new technique for separating and recovering radioactive materials using aerosols. However, there is a need for a technique that can separate and recover radioactive materials more efficiently.

[0009] The present invention has been made in response to the above-mentioned conventional circumstances, and has an object to provide an apparatus and method for separating and recovering radioactive materials that can efficiently separate and recover radioactive materials. [Means for solving the problem]

[0010] An embodiment of the radioactive material separation and recovery device is a radioactive material separation and recovery device that separates and recovers radioactive material contained in a target, and is characterized by comprising: a target heating unit that heats the target accommodated therein to vaporize the radioactive material; a radioactive material recovery unit that is arranged above the target heating unit and cools and recovers the radioactive material vaporized by the target heating unit; a piping unit that communicates between the target heating unit and the radioactive material recovery unit; a heating device that is arranged along the length of the piping unit; a radiation detector that is provided in the piping unit and detects adhesion of radioactive material; and a heating control device that drives the heating device based on a detection signal from the radiation detector. [Effects of the Invention]

[0011] According to the embodiments of the present invention, it is possible to provide an apparatus and a method for separating and recovering radioactive materials that can efficiently separate and recover radioactive materials. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a diagram schematically showing the general configuration of a radioactive substance separation and recovery device according to a first embodiment; [Figure 2] FIG. 10 is a diagram schematically illustrating the general configuration of a radioactive substance separation and recovery device according to a second embodiment. [Figure 3] FIG. 10 is a diagram schematically illustrating the general configuration of a radioactive substance separation and recovery device according to a third embodiment. [Figure 4] FIG. 10 is a diagram schematically illustrating the general configuration of a radioactive substance separation and recovery device according to a fourth embodiment. [Figure 5] FIG. 10 is a diagram schematically illustrating the general configuration of a radioactive substance separation and recovery device according to a fifth embodiment. [Figure 6] FIG. 10 is a diagram schematically illustrating the general configuration of a radioactive substance separation and recovery device according to a sixth embodiment. [Figure 7] FIG. 13 is a perspective view schematically showing the general configuration of an apparatus for separating and recovering radioactive substances according to a seventh embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, an apparatus and a method for separating and recovering radioactive materials according to an embodiment will be described with reference to the drawings.

[0014] (First embodiment) First, a first embodiment will be described with reference to Fig. 1. Fig. 1 is a diagram showing a schematic configuration of a radioactive material separation and recovery apparatus 100 according to the first embodiment. The radioactive material separation and recovery apparatus 100 is an apparatus for separating and recovering radioactive materials by utilizing the difference in melting point and boiling point between a target material and the radioactive materials contained therein, and can be suitably used, for example, to separate and recover astatine-211 contained in the target material by utilizing the difference in melting point and boiling point between the target material and bismuth.

[0015] 1, a radioactive material separation and recovery device 100 includes a target heating unit 110 that forms a space capable of accommodating a target 140 therein. A radioactive material recovery unit 120 is provided so as to be positioned above the target heating unit 110. A plurality of (two in this embodiment) piping units 130a and 130b are provided so as to connect the target heating unit 110 and the radioactive material recovery unit 120. The target 140 may be, for example, an irradiated target obtained by irradiating bismuth with alpha rays to generate astatine-211.

[0016] The target heating unit 110 is provided with a heating control device 111, a heater 112 as a heating device, and a radiation detector 113. The heating control device 111 monitors the state of evaporation of the radioactive material by monitoring the radiation detected by the radiation detector 113, and controls the heating temperature of the target 140 by the heater 112.

[0017] The radioactive material recovery section 120 is provided with a cooling control device 121, a refrigerant 122 as a cooling device, and a radiation detector 123. The cooling control device 121 monitors the state of recovery of the radioactive material by monitoring the radiation detected by the radiation detector 123, and controls the temperature of the refrigerant 122 by the cooling control device 121.

[0018] The piping sections 130a and 130b that communicate between the target heating section 110 and the radioactive material recovery section 120 serve as a flow path for gas circulating between the target heating section 110 and the radioactive material recovery section 120 due to the temperature difference. This circulated gas is the internal atmosphere containing radioactive material vapor that has been heated and evaporated in the target heating section 110.

[0019] A plurality of radiation detectors 132a and a plurality of heaters 133a as heating devices are arranged along the length of piping section 130a, and these are connected to heating control device 131a. Similarly, a plurality of radiation detectors 132b and a plurality of heaters 133b as heating devices are arranged along the length of piping section 130b, and these are connected to heating control device 131b. Note that instead of providing a plurality of radiation detectors 132a and 132b, a configuration may be adopted in which a single detector that can move along piping section 130a and piping section 130b is provided.

[0020] As the radiation detectors 113, 123, 132a, and 132b, for example, radiation detectors capable of detecting X-rays or gamma rays can be used.

[0021] In the radioactive material separation and recovery device 100 configured as described above, an irradiated target 140 containing the radioactive material to be separated is loaded into the target heating unit 110, and the target is heated by a heater 112 to evaporate the radioactive material from the target 140. At this time, a radiation detector 113 installed near the target heating unit 110 monitors radiation originating from the radioactive material to be separated, and a heating control device 111 controls the heating temperature.

[0022] As described above, radioactive material evaporated from target 140 heated by target heating unit 110 passes through piping unit 130a or piping unit 130b due to convection caused by a temperature difference and reaches radioactive material recovery unit 120. At this time, the state of adhesion of radioactive material to piping unit 130a and piping unit 130b is monitored by radiation detectors 132a and 132b, and for areas where adhesion of radioactive material is detected, heating control device 131a, heating control device 131b and heaters 133a and 133b heat piping unit 130a and piping unit 130b. This makes it possible to suppress adhesion of radioactive material to piping unit 130a and piping unit 130b and efficiently separate and recover the radioactive material.

[0023] In this embodiment, also in the radioactive material recovery unit 120, the radiation detector 123 monitors the attached radioactivity in the same way, and recovers the radioactive material while controlling the cooling state by the cooling control device 121 and the refrigerant 122.

[0024] For example, when bismuth is irradiated with alpha rays to generate astatine-211 and then collected, the heating temperature of the target heating section 110 is, for example, about 500-750°C, the cooling temperature of the radioactive material collection section 120 is, for example, below 0°C, and the heating temperature of the piping sections 130a and 130b is, for example, about 100-200°C.

[0025] (Second embodiment) Next, a radioactive material separation and recovery apparatus 200 according to a second embodiment will be described. Fig. 2 is a diagram schematically showing the general configuration of the radioactive material separation and recovery apparatus 200 according to the second embodiment, and parts corresponding to those of the first embodiment shown in Fig. 1 are given the same reference numerals and redundant explanations will be omitted.

[0026] In the radioactive material separation and recovery device 200 of the second embodiment, shields 150 for blocking radiation are installed between the radiation detectors 132a and between the radiation detectors 132b. These shields 150 block radiation from areas other than those being measured by the radiation detectors 132a and 132b, thereby improving the accuracy of measuring the amount of radioactive material attached to each part of the piping section 130a and the piping section 130b. This makes it possible to accurately suppress the attachment of radioactive material due to heating.

[0027] In the radioactive material separation and recovery device 200 of the second embodiment, a shield 150 is also installed between the radiation detector 113 of the target heating unit 110 and the radiation detector 123 of the radioactive material recovery unit 120.

[0028] (Third embodiment) Next, a radioactive material separation and recovery apparatus 300 according to a third embodiment will be described. Fig. 3 is a diagram schematically showing the general configuration of the radioactive material separation and recovery apparatus 300 according to the third embodiment, and parts corresponding to those of the first and second embodiments shown in Figs. 1 and 2 are given the same reference numerals and redundant explanations will be omitted.

[0029] 3, in the radioactive material separation and recovery device 300 of the third embodiment, the cross-sectional areas of the flow paths of the piping sections 130a and 130b are gradient, and the piping diameters (flow path cross-sectional areas) shown in Fig. 3 are configured as D1>D2>D3>D4 so that the cross-sectional areas of the flow path from the target heating section 110 to the radioactive material recovery section 120 and the flow path from the radioactive material recovery section 120 back to the target heating section 110 gradually decrease. With this configuration, for example, a smooth flow of gas ascending from the target heating section 110 through the piping section 130b with a large flow path cross-sectional area and descending through the piping section 130a with a small flow path cross-sectional area can be formed, preventing backflow.

[0030] (Fourth embodiment) Next, a radioactive material separation and recovery apparatus 400 according to a fourth embodiment will be described. Fig. 4 is a diagram schematically showing the general configuration of the radioactive material separation and recovery apparatus 400 according to the fourth embodiment, and parts corresponding to those of the first to third embodiments shown in Figs. 1 to 3 are given the same reference numerals and redundant explanations will be omitted.

[0031] As shown in Fig. 4, in the radioactive material separation and recovery apparatus 400 of the fourth embodiment, in addition to the configuration of the radioactive material separation and recovery apparatus 300 of the third embodiment shown in Fig. 3, the coolant 122 in contact with the radioactive material recovery section 120 and the heater 112 in contact with the target heating section 110 are installed so as to be asymmetric with respect to the circulation pipe consisting of the pipe section 130a and the pipe section 130b. With such a configuration, thermal convection of the gas can be actively generated, and radioactive materials can be recovered more efficiently.

[0032] (Fifth embodiment) Next, a radioactive material separation and recovery apparatus 500 according to a fifth embodiment will be described. Fig. 5 is a diagram schematically showing the general configuration of the radioactive material separation and recovery apparatus 500 according to the fifth embodiment, and parts corresponding to those of the first to fourth embodiments shown in Figs. 1 to 4 are given the same reference numerals and redundant explanations will be omitted.

[0033] 5, the radioactive material separation and recovery device 500 of the fifth embodiment is configured such that an irradiation window 160 is provided in the target heating unit 110. By irradiating the target 140 with an irradiation beam 170 such as an alpha beam of a predetermined energy through this irradiation window 160, radioactive materials such as astatine-211 can be generated and then separated and recovered. Therefore, radioactive materials such as astatine-211 with a short half-life can be separated and recovered more efficiently.

[0034] (Sixth embodiment) Next, a radioactive material separation and recovery apparatus 600 according to a sixth embodiment will be described. Figures 6 and 7 are diagrams schematically showing the general configuration of the radioactive material separation and recovery apparatus 600 according to the sixth embodiment, and parts corresponding to those of the first to fifth embodiments shown in Figures 1 to 5 are assigned the same reference numerals and redundant explanations will be omitted. Figure 6 is a perspective view schematically showing the general configuration of the radioactive material separation and recovery apparatus 600, and Figure 7 is a side view. In order to make it easier to understand the positional relationship between the target heating unit 110, the radioactive material recovery unit 120, the piping unit 130a, and the piping unit 130b, some of the components shown in the first to fifth embodiments shown in Figures 1 to 5 are not shown.

[0035] In the first to fifth embodiments described above, the radioactive material recovery unit 120 is provided directly above the target heating unit 110, but this is not necessarily the case. In the sixth embodiment, the radioactive material recovery unit 120 is provided diagonally above the target heating unit 110.

[0036] Furthermore, in the sixth embodiment, of the piping section 130a and the piping section 130b, the piping section 130b is provided higher than the other piping section 130a. In this case, the piping section 130b provided higher serves as a flow path for gas heated in the target heating section 110 to the radioactive material recovery section 120, and the piping section 130a provided lower serves as a flow path for gas cooled in the radioactive material recovery section 120 to the target heating section 110. With this configuration, gas circulation can be more smoothly generated, and radioactive materials can be separated and recovered efficiently.

[0037] Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, modifications, and combinations can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0038] 100, 200, 300, 400, 500, 600...Radioactive material separation and recovery device, 110...Target heating section, 111...Heating control device, 112...Heater, 113...Radiation detector, 120...Radioactive material recovery section, 121...Cooling control device, 122...Refrigerant, 130a, 130b...Piping section, 131a, 131b...Heating control device, 132a, 132b...Radiation detector, 133a, 133b...Heater, 140...Target, 150...Shielding body, 160...Irradiation window, 170...Irradiation beam.

Claims

1. A radioactive material separation and recovery device that separates and recovers radioactive materials contained in a target, a target heating unit that heats the target accommodated therein to vaporize the radioactive material; a radioactive material recovery unit disposed above the target heating unit, which cools and recovers the radioactive material vaporized by the target heating unit; a piping section communicating between the target heating section and the radioactive material recovery section; a heating device disposed along the length of the piping section; a radiation detector provided in the piping section for detecting adhesion of radioactive materials; a heating control device that drives the heating device based on a detection signal from the radiation detector; A radioactive material separation and recovery device comprising:

2. 2. The apparatus for separating and recovering radioactive materials according to claim 1, further comprising a shielding member provided around the radiation detector for blocking radiation from areas other than the measurement area.

3. 2. The apparatus for separating and recovering radioactive materials according to claim 1, wherein a plurality of the piping sections are provided, and the cross-sectional areas of the flow paths of the piping sections are configured to gradually decrease.

4. 2. The radioactive material separation and recovery device according to claim 1, wherein a plurality of the piping sections are provided, and a heating mechanism provided in the target heating section and a cooling mechanism provided in the radioactive material recovery section are provided at asymmetric positions with respect to the piping sections.

5. 2. The radioactive material separation and recovery device according to claim 1, wherein the target heating unit is provided with an irradiation window for irradiating the target with an irradiation beam.

6. A method for separating and recovering radioactive materials contained in a target, comprising: a target heating unit that heats the target accommodated therein to vaporize the radioactive material; a radioactive material recovery unit disposed above the target heating unit, which cools and recovers the radioactive material vaporized by the target heating unit; a piping section communicating between the target heating section and the radioactive material recovery section; a heating device disposed along the length of the piping section; a radiation detector provided in the piping section for detecting adhesion of radioactive materials; Using a device equipped with The heating device is driven based on a detection signal from the radiation detector, and adhesion of radioactive materials to the piping is suppressed. A method for separating and recovering radioactive materials, comprising:

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