Manufacturing device for calibration source of radioactive monitor

Abstract

The invention provides a manufacturing device of a calibration source of a radioactive monitor, the manufacturing device comprises an aerosol generating unit, an aerosol processing unit and a calibration source manufacturing unit, the aerosol generating unit comprises a first container and an atomization assembly, the first container is provided with a storage cavity, and the atomization assembly is used for atomizing a radioactive standard solution to form aerosol; the aerosol treatment unit comprises a second container, the second container is provided with a treatment space, and the treatment space is communicated with the storage cavity; the calibration source manufacturing unit comprises a sealing assembly and is provided with a deposition space capable of being opened and closed, the deposition space is communicated with the treatment space, at least part of the deposition space used for calibrating the filter membrane can be detachably arranged in the deposition space and divides the deposition space into an upstream space and a downstream space, and the upstream space is communicated with the treatment space. According to the manufacturing device provided by the embodiment of the invention, the deposition state of the radionuclide deposited on the calibration filter membrane is similar to the deposition state in the actual working process.

Description

Technical Field

[0001] This application relates to radioactive monitoring technology, and more particularly to an apparatus for manufacturing a calibration source for a radioactive monitoring instrument. Background Technology

[0002] In applications such as radioactive aerosol monitoring and environmental radioactivity measurement, radioactive monitoring instruments typically collect particulate radioactive materials from the air through filter membranes during actual operation and measure the deposited layer formed on the filter membrane. To ensure the traceability and consistency of measurement results, radioactive monitoring instruments need to undergo verification, calibration, or performance checks.

[0003] In related technologies, an electroplated planar source, formed by depositing radioactive material onto the surface of an electroplated substrate through electroplating, is used as a calibration source. However, the electroplating process differs from the way aerosols are deposited on filter membranes in actual operation of radioactive monitoring instruments. The spatial distribution, areal density, and equivalent thickness of radioactive material on the electroplated substrate may deviate from the state formed during actual sampling, leading to inconsistencies between the self-absorption and detection efficiency characteristics and the actual sample, and affecting the accuracy of the calibration results. Summary of the Invention

[0004] This application provides an apparatus for manufacturing a calibration source for a radioactive monitor. The manufactured calibration source is more consistent with real working conditions, which helps to improve the accuracy of calibration results.

[0005] The technical solution of this application embodiment is implemented as follows: This application provides an apparatus for manufacturing a calibration source for a radioactive monitor, used to fabricate a calibration filter membrane into a calibration source, comprising: An aerosol generating unit includes a first container and an atomizing component. The first container is provided with a storage chamber, and the atomizing component is used to atomize a radioactive standard solution in the storage chamber to form an aerosol. An aerosol treatment unit includes a second container, the second container having a treatment space, the treatment space being connected to the storage cavity to allow aerosols to enter the treatment space; The calibration source manufacturing unit includes a sealing assembly and has an openable and closable deposition space that is connected to the processing space. At least a portion of the calibration filter membrane is detachably disposed within the deposition space, which divides the deposition space into an upstream space and a downstream space, the upstream space being connected to the processing space.

[0006] In some embodiments, the manufacturing apparatus includes a first conduit connecting the storage cavity and the processing space, at least a portion of the first conduit extending in a vertical direction.

[0007] In some embodiments, the second container further includes a confluence space located below and connected to the processing space.

[0008] In some embodiments, the inner wall of the processing space is covered with a hydrophobic layer.

[0009] In some embodiments, the manufacturing apparatus further includes a second conduit and a particle size spectrometer, the second conduit connecting the upstream space and the processing space, and the particle size spectrometer being used to acquire particle size distribution data of aerosols entering the upstream space via the second conduit.

[0010] In some embodiments, the manufacturing apparatus further includes a detection conduit, both ends of which are selectively connected to or closed to the second conduit, and the particle size spectrometer is connected to the detection conduit.

[0011] In some embodiments, the calibration source manufacturing unit further includes a switching mechanism and a measurement station. The measurement station is equipped with an activity measuring device. The switching mechanism is used to drive the calibration filter membrane in the deposition space to move to the measurement station so that the activity measuring device can detect the activity of the calibration filter membrane.

[0012] In some embodiments, the manufacturing apparatus further includes a first temperature and humidity sensor in communication with the deposition space.

[0013] In some embodiments, the manufacturing apparatus further includes a filtration unit in communication with the downstream space, the filtration unit being used to collect aerosol particles.

[0014] In some embodiments, the manufacturing apparatus further includes an emission unit; The discharge unit includes a discharge pipe and a first fan. The discharge pipe connects the outlet of the filter unit to the outside of the manufacturing device, and the first fan is used to drive the gas in the discharge pipe. And / or, the emission unit includes a circulation duct and a second fan, the circulation duct connecting the outlet of the filter unit to at least one of the storage chamber and the processing space, and the second fan driving the gas within the circulation duct.

[0015] The manufacturing apparatus in this embodiment can form an aerosol similar to the working environment of the radioactive monitor through the atomization component. The processing space reduces the number of large-diameter aerosol particles in the aerosol, which is beneficial for forming an aerosol that is more similar to the actual working environment. This is beneficial for ensuring that the deposition state of radionuclides on the calibration filter membrane is similar to the deposition state in the actual working process, thus improving calibration accuracy. The aerosol is confined within the storage space, processing space, and deposition space, reducing the risk of radionuclide diffusion and contributing to environmental protection. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the manufacturing method steps provided in the embodiments of this application; Figure 2 This is a schematic diagram of the manufacturing apparatus provided in the embodiments of this application, wherein the first container, the second container, the calibration filter membrane and the sealing assembly are shown in cross-section, and the arrows indicate the flow direction of the airflow and aerosol; Figure 3 This is a cross-sectional schematic diagram of the calibration filter membrane and sealing assembly provided in the embodiments of this application; Figure 4 Figure 3 A cross-sectional view of position AA in the middle.

[0017] Explanation of reference numerals in the attached figures 10. Aerosol generating unit; 11. First container; 11a. Storage chamber; 12. Atomizing assembly; 20. Aerosol processing unit; 21. Second container; 21a. Processing space; 21b. Confluence space; 22. Hydrophobic layer; 30. Calibration source manufacturing unit; 31. Sealing assembly; 31a. Deposition space; 31aa. Upstream space; 31ab. Downstream space; 311. First shell; 312. Second shell; 313. Confinement ring; 31 3a. First flow passage; 314. Elastic sealing ring; 32. Measuring station; 321. Activity meter; 40. Calibration filter membrane; 41. Deposition area; 50. First pipe; 60. Second pipe; 61. Particle size spectrometer; 62. Detection pipe; 70. Filtration unit; 80. Discharge pipe; 81. Circulation pipe; 90. First temperature and humidity sensor; 91. Second temperature and humidity sensor; 92. Flow controller; 100. Radioactive standard solution. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. The described embodiments should not be regarded as limitations on this application. All other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this application; the terms “comprising” and “having”, and any variations thereof, in the specification and the foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0020] In the description of the embodiments of this application, the technical terms "first," "second," "third," etc., are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0021] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0022] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects are in an "or" relationship.

[0023] In the description of the embodiments of this application, the technical terms "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "top", "bottom", "inner", "outer", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed, operated or used in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0024] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0025] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical term "contact" should be interpreted broadly, and can be direct contact, contact through an intermediate medium layer, contact between two contacting parties with substantially no interaction force, or contact between two contacting parties with interaction force.

[0026] In the embodiments of this application, "parallel" includes not only the case of absolute parallelism, but also the case of approximate parallelism as commonly understood in engineering; similarly, "perpendicular" also includes not only the case of absolute perpendicularity, but also the case of approximate perpendicularity as commonly understood in engineering. Specifically, if the angle between two directions is 85°-90°, the two directions can be considered perpendicular; if the angle between two directions is 0°-5°, the two directions can be considered parallel.

[0027] In the description of the embodiments of this application, for ease of explanation, as shown in the accompanying drawings, the direction of arrow X is referred to as the "vertical direction".

[0028] This application provides a method for manufacturing a calibration source for a radioactive monitoring instrument. (See attached document.) Figure 1 The manufacturing method includes: S10: Preparation of radioactive standard solutions; S20: Atomize the radioactive standard solution to form the first aerosol; S30: Reduce the number of aerosol particles in the first aerosol that are larger than the preset particle size until the aerosol meets the preset particle size distribution requirements to obtain the second aerosol. S40: Drive the second aerosol through the calibration filter membrane so that the calibration filter membrane absorbs aerosol particles to form a calibration source.

[0029] A radioactive standard solution of 100 is prepared according to the radioactive nuclides that the radioactive monitoring instrument needs to detect in the working environment. The specific types of radioactive nuclides included are not limited, for example... 137 Cs and 241 Am et al.

[0030] Understandably, the solution ratio containing radionuclides can be adaptively diluted or adjusted according to the working environment that the radioactive monitoring instrument needs to detect and the radionuclides that need to be detected.

[0031] Atomize the radioactive standard solution 100 so that droplets containing anti-radioactive nuclides and solid particles mix with air to form an aerosol, thereby obtaining the first aerosol.

[0032] In related technologies, radioactivity monitors incorporate a filter membrane. During operation, airflow enters the monitor, and the filter membrane adsorbs aerosols containing radionuclides. The monitor then detects the adsorbed radionuclides on the filter membrane to obtain data such as radioactivity distribution and activity in the working environment. Therefore, the more similar the deposition and distribution of radionuclides on the filter membrane under actual operating conditions is to the calibration source used to calibrate the monitor, the higher the accuracy of the calibration, and the more precise the subsequent actual detection results from the radioactivity monitor.

[0033] Understandably, the first aerosol formed after atomization contains a large number of large-diameter droplets and solid particles, while large-diameter droplets and solid particles are rarely present in the actual working environment of a radioactivity monitor. Therefore, the spatial distribution of these large-diameter droplets and solid particles deposited on the calibration filter membrane 40 differs significantly from the spatial distribution of nuclide deposition in the filter membrane of the aerosol detected by the radioactivity monitor under actual operating conditions. The physical properties of large-diameter droplets differ significantly from those of aerosol particles in the actual working environment, and the self-absorption characteristics of the calibration filter membrane 40 after absorbing large-diameter droplets are also different from those of the filter membrane in the actual working environment. Large-diameter droplets can wet the calibration filter membrane 40 and increase air resistance, potentially damaging the calibration filter membrane 40.

[0034] Therefore, by reducing the number of aerosol particles with a diameter larger than the preset diameter in the first aerosol, a second aerosol is obtained. The droplet diameter in the second aerosol is similar to the aerosol size detected by the radioactivity monitor under actual operating conditions. This makes the deposition state of the aerosol particles in the second aerosol on the calibration filter membrane 40, such as the depth of penetration and distribution, similar to the deposition state formed by the filter membrane of the radioactivity monitor under actual operating conditions.

[0035] The calibration filter membrane 40 refers to the filter membrane substrate used to make the calibration source. The material used in the calibration filter membrane 40 is the same as or similar to the material, size and porosity of the filter membrane in the radioactive monitor to be calibrated.

[0036] The second aerosol passes through the calibration filter membrane 40. Compared with directly adding the radioactive standard solution 100 to the calibration filter membrane 40 through coating, dripping or other methods, the water content is lower and it can more closely resemble the deposition state of aerosols on the filter membrane during the actual operation of the radioactive monitor.

[0037] Understandably, the calibration filter 40 and the radionuclides deposited on the calibration filter 40 together form the calibration source.

[0038] The manufacturing method in this embodiment involves passing a second aerosol, obtained by atomizing a radioactive standard solution 100 and reducing aerosol particles larger than a preset size, through a calibration filter membrane 40. This makes the prepared calibration source more closely resemble the state of the radioactive monitor after the filter membrane adsorbs aerosol particles containing radionuclides under actual operating conditions, in terms of nuclide distribution layer structure and self-absorption characteristics. Compared with using an electroplated planar source, this reduces the deviation caused by differences in layer structure morphology during calibration. Furthermore, compared with adding radionuclides to the calibration filter membrane 40 through coating, dripping, or other methods, this reduces the migration and distribution changes of radionuclides caused by subsequent drying of the calibration source. This results in a more uniform distribution of radionuclides on the calibration source and less nuclide enrichment, which is beneficial for improving the consistency between the manufactured calibration sources.

[0039] In some embodiments, the material and model of the calibration filter membrane 40 are the same as those of the filter membrane in the radioactivity monitor.

[0040] During the atomization of radioactive standard solution 100, the radioactive solution should be kept in an atomizable state; and the corresponding control liquid supply method, liquid supply volume or liquid supply stability should be selected according to the specific atomization method to make the atomization process continuous, stable and repeatable.

[0041] The specific method for nebulizing the radioactive standard solution 100 is not limited, such as pneumatic nebulization, ultrasonic nebulization, sieve plate throttling nebulization, etc. It is understandable that different nebulization methods require different operating parameters to maintain stability during the nebulization process. For example, in pneumatic nebulization, the supply gas pressure and nebulizing gas flow rate; in ultrasonic nebulization, the operating frequency and power; and in sieve plate throttling nebulization, the channel parameters and pressure difference conditions.

[0042] The specific methods for reducing the number of aerosol particles larger than the preset particle size in the first aerosol are not limited. For example, inertial separation can be achieved by utilizing the different masses of aerosol particles of different sizes, or separation can be achieved by sieving and throttling.

[0043] In some embodiments, the step of reducing aerosol particles with a diameter larger than a preset diameter in the first aerosol specifically includes: Drive the first aerosol through the processing space 21a; Based on the volume of the processing space 21a, the flow rate of the first aerosol entering the processing space 21a is adjusted so that aerosol particles with a particle size larger than the preset particle size in the first aerosol will coagulate and separate from the first aerosol in the processing space 21a.

[0044] During the processing of the first aerosol in the processing space 21a, aerosol particles larger than the preset particle size are more likely to collide and merge with each other to form larger aerosol particles. The larger aerosol particles formed can fall to the bottom of the processing space 21a under the action of gravity, thereby separating from the aerosol particles smaller than the preset particle size in the first aerosol.

[0045] In this way, the natural coagulation between aerosol particles can be used to reduce the number of aerosol particles larger than the preset particle size, which simplifies the required equipment and manufacturing conditions and reduces the manufacturing difficulty.

[0046] It is understandable that the agglomeration effect of the aerosol particles of the first aerosol is related to the residence time of the first aerosol in the processing space 21a. By adjusting the volume size of the processing space 21a and the flow rate of the first aerosol entering the processing space 21a, the residence time of the first aerosol in the processing space 21a can be adjusted.

[0047] The first aerosol formed after nebulizing the radioactive standard solution 100 consists of coarse droplets, which are relatively large in size.

[0048] In some embodiments, before driving the first aerosol through the processing space 21a, the manufacturing method further includes: driving the first aerosol to move vertically for at least a portion of the travel before the first aerosol enters the processing space 21a.

[0049] Because of their larger size and mass, coarse droplets are more difficult to flow during their ascent compared to other aerosol particles, and even more difficult to flow again after falling, which leads to the separation of coarse droplets from the aerosol particles in the first aerosol.

[0050] In this way, without the need for complex mechanisms, the coarse droplets in the first aerosol can be separated in advance, which is beneficial to improving the coagulation efficiency between aerosol particles in the subsequent processing space 21a.

[0051] Coarse droplets refer to droplets with a diameter of not less than 2.5 μm (micrometer).

[0052] In some embodiments, driving the first aerosol to move in the vertical direction for at least a portion of the stroke includes: driving the first aerosol to reciprocate in the vertical direction for at least a portion of the stroke.

[0053] In other words, the first aerosol must complete at least one ascent and descent process.

[0054] This is beneficial for improving the efficiency of separating coarse droplets from the first aerosol.

[0055] In some embodiments, the preset particle size is 2.5 μm or 3 μm.

[0056] This makes the deposition state of the aerosol particles that are finally deposited on the calibration filter membrane 40 closer to the deposition state formed by the filter membrane in the radioactivity monitor absorbing aerosols in the actual environment.

[0057] In some embodiments, determining that the aerosol meets the preset particle size distribution requirements specifically includes: Obtain the first particle size distribution data of aerosol particles in the second aerosol whose particle size is larger than the preset particle size; Compare the number of particles in each particle size interval in the first particle size distribution data, and the maximum number obtained is the first peak value; Obtain the second particle size distribution data of aerosol particles in the second aerosol whose particle size is smaller than the preset particle size; By comparing the number of particles in each particle size interval in the second particle size distribution data, the maximum number obtained is the second peak value; It is determined that the first peak value is smaller than the second peak value.

[0058] The first particle size distribution data refers to the number of aerosol particles in each particle size interval, which is divided into multiple continuous particle size intervals for particles larger than the preset particle size.

[0059] The first peak value refers to the number of aerosol particles in the first particle size distribution data that has the largest number of aerosol particles.

[0060] The second particle size distribution data refers to the number of aerosol particles in each particle size interval, which is divided into multiple continuous particle size intervals for particles smaller than the preset particle size.

[0061] The second peak refers to the number of aerosol particles in the second particle size distribution data that has the largest number of aerosol particles.

[0062] The fact that the first peak value is less than the second peak value indicates that the number of aerosol particles in any particle size range in the first particle size distribution data is less than the particle size range with the most aerosol particles in the second particle size distribution data.

[0063] This indirectly indicates that the number of aerosol particles larger than the preset particle size in the second aerosol is less than the number of aerosol particles smaller than the preset particle size.

[0064] Understandably, the size range and number of particle size intervals in the first and second particle size distribution data can be divided according to requirements.

[0065] In some embodiments, in the second particle size distribution data, multiple particle size intervals include a first particle size interval, the size range of which is 0.1 μm to 1 μm.

[0066] In some embodiments, the second peak value is located within the first particle size range.

[0067] In some embodiments, determining that the first peak value does not exceed the second peak value specifically includes: The first peak value is determined to be no more than 10% of the second peak value.

[0068] Thus, the number of aerosol particles larger than the preset particle size in the second aerosol is significantly less than the number of aerosol particles smaller than the preset particle size. This further helps to make the prepared calibration source more closely resemble the state of the radioactive monitoring instrument after the filter membrane adsorbs aerosol particles containing radionuclides under actual operating conditions, in terms of the layer structure of nuclide distribution and self-absorption characteristics.

[0069] Understandably, particle size distribution data of aerosol particles in aerosols are obtained by measuring particle size distribution using particle size spectrometer 61.

[0070] It is understandable that radioactive nuclides could contaminate the particle size spectrometer 61, causing adverse effects on it.

[0071] In some embodiments, the manufacturing method further includes, prior to atomizing the radioactive standard solution 100 to form the first aerosol: Prepare a test solution that does not contain radioactive nuclides; The test solution is atomized to form the first test aerosol; Drive the first test aerosol through the processing space 21a; The particle size distribution data of the first test aerosol is detected by particle size spectrometer 61. Based on the volume of the processing space 21a, the flow rate of the first test aerosol entering the processing space 21a is adjusted until the first test aerosol meets the preset particle size distribution requirements. The flow rate of the first test aerosol is then determined as the first flow rate value. Adjusting the flow rate of the first aerosol entering the processing space 21a specifically includes: The first aerosol is delivered into the processing space 21a according to the first flow rate value.

[0072] The difference between the test solution and the radioactive standard solution 100 is that the test solution does not contain radioactive nuclides.

[0073] It is understandable that the mass percentage of radioactive nuclides in aerosol particles is very small, making it difficult to affect the overall physical properties of the aerosol.

[0074] Therefore, by first delivering a first test aerosol without radioactive nuclides into the processing space 21a, a first flow rate value corresponding to the preset particle size requirement is obtained. In subsequent steps, the first aerosol is delivered into the processing space 21a according to the first flow rate value, so that the aerosol meets the preset particle size distribution requirement.

[0075] Thus, there is no need to monitor the particle size distribution of radioactive aerosols in the processing space 21a in real time, thereby eliminating the need for the particle size spectrometer 61 to come into contact with radioactive nuclides.

[0076] Understandably, by adjusting the flow rate and time of the second aerosol passing through the calibration filter membrane 40, the activity of the radionuclides deposited by the calibration source can be controlled.

[0077] In some embodiments, after driving the second aerosol through the calibration filter membrane 40, the manufacturing method further includes: maintaining a stable flow rate of the second aerosol passing through the calibration filter membrane 40 and maintaining a preset deposition time.

[0078] This reduces the probability of radionuclides shifting or expanding on the calibration filter membrane 40 due to flow fluctuations or abnormal pressure drops.

[0079] In some embodiments, see Figure 4 The calibration filter membrane 40 includes a deposition region 41 through which the second aerosol passes. The projection of the deposition region 41 along the flow direction of the second aerosol is circular.

[0080] This makes it easier to ensure that the shape of the deposition area 41 is the same as the shape of the monitoring deposition area 41 of the filter membrane in the radioactivity monitor, which helps to improve the accuracy of the calibration results and makes it easier to reduce the response dispersion caused by geometric factors in calibration sources prepared in different batches.

[0081] As the second aerosol passes through the calibration filter membrane 40, at least some of the radionuclides will be deposited in the deposition region 41 to form a radioactive active layer.

[0082] In some embodiments, the size of the deposition area 41 does not exceed the size of the monitoring deposition area 41 of the filter membrane in the radioactivity monitor, so that the subsequent calibration process of the radioactivity monitor is similar to the conditions of aerosol absorption during the actual operation of the radioactivity monitor, thereby improving the accuracy of the calibration.

[0083] In some embodiments, the manufacturing method further includes, before driving the second aerosol through the calibration filter membrane 40: At least a portion of the calibration filter membrane 40 is installed in the deposition space 31a, and the portion of the calibration filter membrane 40 located in the deposition space 31a forms a deposition region 41, sealing the deposition region 41 with the inner wall of the deposition space 31a.

[0084] By sealing the inner wall between the deposition area 41 and the deposition space 31a, the deposition range of aerosol particles on the calibration filter membrane 40 can be limited to the deposition area 41, thus suppressing the probability of aerosol particles diffusing to other areas of the calibration filter membrane 40.

[0085] In some embodiments, the calibration filter membrane 40 separates the deposition space 31a to form an upstream space 31aa, the upstream space 31aa being located on the upstream side of the calibration filter membrane 40 along the flow direction of the second aerosol; Following the step of sealing the inner wall of the deposition region 41 and the deposition space 31a, the manufacturing method further includes: Drive the second aerosol through the calibration filter membrane 40, control the flow rate of the second aerosol within the first preset flow rate range and maintain the preset sampling time, and acquire the first temperature data and the first humidity data in the upstream space 31aa; The first temperature data is determined to be within the first preset temperature range, and the first humidity data is determined to be within the first preset humidity range.

[0086] After the second aerosol enters the upstream space 31aa, it passes through the calibration filter membrane 40.

[0087] Changes in temperature and humidity can directly affect the morphology of aerosol particles in the second aerosol. When humidity increases, aerosol particles are more likely to merge and form larger droplets, thereby changing the particle size distribution of aerosol particles in the second aerosol.

[0088] Thus, by monitoring the first temperature and first humidity data, it is helpful to indirectly determine whether the particle size of the aerosol in the second aerosol meets the preset particle size distribution requirements, so as to use it as a reference to determine whether to stop the manufacturing process.

[0089] In some embodiments, after the step of causing the calibration filter membrane 40 to absorb aerosol particles to form a calibration source, the manufacturing method further includes: Once it is determined that the second aerosol has passed through the calibration filter membrane 40 for a preset deposition time, the process of driving the second aerosol through the calibration filter membrane 40 is stopped.

[0090] This terminates the deposition process of aerosol particles on the calibration filter membrane 40, reducing the probability of continued changes in the radioactivity of the calibration source.

[0091] The way to stop the second aerosol from passing through the calibration filter membrane 40 is to stop the second aerosol from entering the deposition space 31a, or to block the channel for the second aerosol to enter the deposition space 31a.

[0092] In some embodiments, after the step of causing the calibration filter membrane 40 to absorb aerosol particles to form a calibration source, the manufacturing method further includes: The actual radioactivity value of the calibration source is detected to determine if it is within the preset radioactivity range.

[0093] In this way, determining the actual radioactivity value of the calibration source can meet the requirements for subsequent calibration of the radioactivity monitoring instrument.

[0094] In some embodiments, after determining that the actual radioactivity value is within a preset radioactivity range, the manufacturing method further includes: Examine the shape and size of the deposition area to ensure it meets the preset geometric constraints.

[0095] Preset geometric constraints are determined based on the installation area of ​​the filter membrane in the radioactivity monitor.

[0096] This ensures that the calibration source meets the size requirements for calibrating and standardizing the radioactivity monitor.

[0097] In some embodiments, after determining that the actual radioactivity value is within a preset radioactivity range, the manufacturing method further includes: Dry the calibration source and package it.

[0098] This reduces interference from the external environment on the calibration source.

[0099] This application also provides an apparatus for manufacturing a calibration source for a radioactive monitor, used to fabricate a calibration filter membrane 40 into a calibration source, see reference. Figure 2 and Figure 3 The manufacturing apparatus includes an aerosol generation unit 10, an aerosol processing unit 20, and a calibration source manufacturing unit 30.

[0100] The aerosol generating unit 10 includes a first container 11 and an atomizing component 12. The first container 11 is provided with a storage chamber 11a, and the atomizing component 12 is used to atomize the radioactive standard solution 100 in the storage chamber 11a to form an aerosol.

[0101] The aerosol processing unit 20 includes a second container 21, which has a processing space 21a. The processing space 21a is connected to the storage cavity 11a so that aerosols can enter the processing space 21a.

[0102] The calibration source manufacturing unit 30 includes a sealing assembly 31 and an openable and closable deposition space 31a. The deposition space 31a is connected to the processing space 21a. At least a portion of the filter membrane 40 is detachably disposed in the deposition space 31a and the deposition space 31a is divided into an upstream space 31aa and a downstream space 31ab. The upstream space 31aa is connected to the processing space 21a.

[0103] Storage chamber 11a is used to store at least radioactive standard solution 100.

[0104] The storage chamber 11a is provided with a carrier gas inlet and an aerosol outlet.

[0105] The carrier gas inlet is used to input the carrier gas. The carrier gas refers to the gas used to mix with the nebulized radioactive standard solution 100 to form the first aerosol. The specific type of carrier gas is not limited, such as air.

[0106] The atomizing component 12 atomizes the radioactive standard solution 100 and mixes it with the gas flow to form a first aerosol. The first aerosol rises to other spaces in the storage chamber 11a. Under the impetus of the carrier gas or energy coupling, the first aerosol is discharged from the storage chamber 11a through the aerosol outlet and enters the processing space 21a.

[0107] It is understandable that the flow rate of the first aerosol discharged from the storage chamber 11a can be indirectly controlled by adjusting the flow rate of the carrier gas.

[0108] The atomizing component 12 can be a pneumatic atomizing structure, an ultrasonic atomizing structure, a sieve plate atomizing structure, a throttling atomizing structure, etc.

[0109] In the processing space 21a, aerosol particles larger than the preset particle size in the first aerosol are deposited to the bottom of the processing space 21a by natural agglomeration. The remaining part of the first aerosol forms the second aerosol. The second aerosol can leave the processing space 21a and enter the deposition space 31a under the impetus of the first aerosol that subsequently enters the processing space 21a.

[0110] Before the second aerosol enters the deposition space 31a, the deposition space 31a is opened, the calibration filter membrane 40 is placed in the deposition space 31a, and then the deposition space 31a is closed.

[0111] The second aerosol enters the upstream space 31aa of the deposition space 31a. The calibration filter membrane 40 has a large number of pores, some of which are interconnected to form an airflow channel connecting the upstream space 31aa and the downstream space 31ab. At least some of the aerosol particles in the second aerosol enter the airflow channel formed by these pores and remain in the pores of the calibration filter membrane 40. The gas molecules pass through the airflow channel and enter the downstream space 31ab.

[0112] The manufacturing apparatus in this embodiment can form an aerosol similar to the working environment of the radioactive monitor through the atomizing component 12, and the processing space 21a reduces the number of aerosol particles with larger diameters in the aerosol. This is beneficial for forming an aerosol that is more similar to the actual working environment, and for ensuring that the deposition state of the radionuclides on the calibration filter membrane 40 is similar to the deposition state in the actual working process, thus improving calibration accuracy. The aerosol is confined within the storage space, processing space 21a, and deposition space 31a, reducing the risk of radionuclide diffusion and contributing to environmental protection.

[0113] It is understandable that both the carrier gas inlet and the aerosol outlet are openable and closable to allow for the input of carrier gas and the output of the first aerosol as needed.

[0114] In some embodiments, the storage chamber 11a is provided with an injection port for injecting radioactive standard solution 100 into the storage chamber 11a; in other embodiments, the first container 11 is detachable so that radioactive standard solution 100 can be replenished to the manufacturing apparatus by replacing the first container 11.

[0115] The carrier gas inlet is connected to an external air source, and the specific type of external air source is not limited, such as a blower, airbag, etc.

[0116] In some embodiments, the first container 11 is a cylindrical stainless steel cavity.

[0117] In some embodiments, the aerosol outlet is located at the top of the first container 11, so that coarse droplets in the first aerosol can fall directly back into the storage chamber 11a under the action of gravity.

[0118] In some embodiments, see Figure 2 The manufacturing apparatus includes a first conduit 50, which connects a storage chamber 11a and a processing space 21a. The first conduit 50 is sealed to both a first container 11 and a second container 21.

[0119] In some embodiments, see Figure 2 At least a portion of the first pipe 50 extends in the vertical direction.

[0120] The first aerosol enters the processing space 21a from the storage chamber 11a, and at least part of it is formed within the first conduit 50.

[0121] This allows the coarse droplets in the first aerosol to move vertically within the first pipe 50, which facilitates the settling of the coarse droplets within the first pipe 50 and reduces the content of coarse droplets in the first aerosol entering the deposition space 31a.

[0122] In some embodiments, the first conduit 50 extends in a tortuous direction in order to better facilitate the settling of coarse droplets within the first conduit 50.

[0123] In some embodiments, see Figure 2 The second container 21 also includes a confluence space 21b, which is located below the processing space 21a and the two are connected.

[0124] In this way, the liquid generated by condensation in the processing space 21a can enter the confluence space 21b, which facilitates the subsequent centralized treatment of the formed radioactive liquid. This reduces the probability that the liquid generated by condensation will remain in the processing space 21a and re-evaporate and merge with the first aerosol, thereby reducing the risk of secondary pollution and facilitating the controllable management of waste liquid.

[0125] The confluence space 21b is equipped with an openable and closable drain port, which can discharge the liquid generated by condensation from the confluence space 21b when the drain port is open.

[0126] In some embodiments, see Figure 2 The inner wall of the processing space 21a is covered with a hydrophobic layer 22.

[0127] This helps reduce the deposition and retention of aerosol particles and their condensates on the inner wall of the treatment space 21a, thereby reducing cross-contamination caused by residue accumulation.

[0128] The hydrophobic layer 22 is made of a hydrophobic material, the specific type of which is not limited, such as PTFE (Polytetrafluoroethylene).

[0129] In some embodiments, see Figure 2 The manufacturing apparatus also includes a second pipe 60 and a particle size spectrometer 61. The second pipe 60 connects the upstream space 31aa and the processing space 21a. The particle size spectrometer 61 is used to acquire particle size distribution data of aerosols entering the upstream space 31aa through the second pipe 60.

[0130] Thus, the particle size distribution data of aerosol particles discharged from the processing space 21a can be detected by the particle size spectrometer 61 to determine whether the aerosol meets the preset particle size distribution requirements.

[0131] The specific principle and structure of particle size spectrometer 61 for detecting the particle size distribution of aerosol particles have been disclosed in related technologies and will not be repeated in the embodiments of this application.

[0132] Understandably, the particle size analyzer 61 can detect the particle size distribution data of aerosol particles in the second aerosol, as well as the particle size distribution data of aerosol particles in the first test aerosol.

[0133] In some embodiments, see Figure 2 The manufacturing apparatus also includes a detection pipe 62, both ends of which are selectively connected to or closed to the second pipe 60, and a particle size spectrometer 61 is connected to the detection pipe 62.

[0134] Thus, by controlling the connection or isolation between the detection pipe 62 and the second pipe 60, the timing of the particle size spectrometer 61 detecting the particle size distribution data of aerosol particles can be controlled.

[0135] The first test aerosol can flow through the second pipe 60, with the detection pipe 62 connected to the second pipe 60; or the second aerosol can flow through the second pipe 60, with the detection pipe 62 isolated from the second pipe 60, in order to reduce the adverse effects of radionuclides entering the particle size spectrometer 61.

[0136] In some embodiments, a three-way valve is provided at the connection point between the detection pipe 62 and the second pipe 60. The three-way valve can switch and shut off to control the connection or isolation between the detection pipe 62 and the second pipe 60.

[0137] In some embodiments, see Figure 2 The calibration source manufacturing unit 30 also includes a switching mechanism and a measurement station 32. The measurement station 32 is equipped with an activity measuring device 321. The switching mechanism is used to drive the calibration filter membrane 40 in the deposition space 31a to move to the measurement station 32 so that the activity measuring device 321 can detect the activity of the calibration filter membrane 40.

[0138] The switching mechanism is used to place the calibration filter membrane 40 from the outside into the predetermined installation position of the deposition space 31a when the deposition space 31a is open; or to remove the calibration source from the deposition space 31a and place it in the measurement station 32.

[0139] The activity of the calibration source is measured by the activity meter 321 to determine whether its actual radioactivity value is within the preset radioactivity range.

[0140] The specific type of activity measuring device 321 is not limited; it can be a PIPS (Passivated Implanted Planar Silicon) detector.

[0141] The specific type of switching mechanism is not limited, such as robotic arms, slides with multiple workstations, etc.

[0142] The specific form of measurement station 32 is not limited, such as a platform structure.

[0143] In some embodiments, switching valves are provided at the inlet of the upstream space 31aa and the outlet of the downstream space 31ab to reduce the risk of second aerosol leakage to the outside of the device and cross-contamination during the removal and placement of the calibration filter membrane 40 from the deposition space 31a.

[0144] In some embodiments, the calibration source manufacturing unit 30 further includes a carrier component for placing the calibration filter membrane 40. When the deposition space 31a is open, the switching mechanism can drive the carrier component to enter or exit the deposition space 31a.

[0145] By having the carrier component move between multiple different workstations, the calibration filter membrane 40 is not directly subjected to the force during the transport process, thus reducing the risk of damage to the calibration filter membrane 40.

[0146] Along the direction of aerosol flow, the thickness of the calibration filter 40 is ranged from 0.1 mm (millimetre) to 0.5 mm to accommodate the installation requirements of the radioactivity monitor and reduce the gas resistance generated by the calibration filter 40.

[0147] The specific thickness of the calibrated filter membrane 40 is not limited, for example, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, etc.

[0148] The specific material of the calibrated filter membrane 40 is not limited, such as glass fiber, cellulose, PTFE, etc.

[0149] Understandably, the pore size in the calibration filter membrane 40 is larger than the aerosol particle size in order to adsorb radionuclides and allow airflow.

[0150] In some embodiments, the filter membrane is circular in shape.

[0151] The specific size of the filter membrane is not limited, such as 3cm (centimeter), 3.5cm, 4cm, 4.7cm, 5cm, etc.

[0152] In some embodiments, the calibration filter membrane 40 includes a deposition region 41, and when the deposition space 31a is closed, the edge of the calibration filter membrane 40 is sealed and fitted to the inner wall of the deposition space 31a.

[0153] In this way, by sealing the inner wall between the deposition area 41 and the deposition space 31a, the deposition range of aerosol particles on the calibration filter membrane 40 can be limited to the deposition area 41, thus suppressing the probability of aerosol particles diffusing to other areas of the calibration filter membrane 40.

[0154] In some embodiments, the projection of the deposition region 41 along the flow direction of the aerosol in the deposition space 31a is circular in a projection plane perpendicular to the flow direction of the aerosol in the deposition space 31a.

[0155] This makes it easier to ensure that the shape of the deposition area 41 is the same as the shape of the monitoring deposition area 41 of the filter membrane in the radioactivity monitor, which helps to improve the accuracy of the calibration results, makes the response dispersion of calibration sources prepared in different batches lower due to geometric factors, and at the same time, helps to reduce the risk of damage to the calibration filter membrane 40 due to stress concentration during the deposition and transportation of aerosol particles.

[0156] In some embodiments, the sealing assembly 31 includes a first housing 311 and a second housing 312. The first housing 311 has a first cavity, which is open to the side facing the second housing 312. The first housing 311 and the second housing 312 can be arranged to form a deposition space 31a along the thickness direction of the calibrated filter membrane 40. The first housing 311 and the second housing 312 can move relative to each other along the thickness direction of the calibrated filter membrane 40 to open and close the deposition space 31a.

[0157] The specific method for achieving a circular shape for the deposition region 41 is not limited.

[0158] For example, see Figure 3 and Figure 4 The sealing assembly 31 also includes a confining ring 313, which is located in the open position of the first cavity. The confining ring 313 has a first flow-through hole 313a that extends along the thickness direction of the calibration filter membrane 40. In the projection plane perpendicular to the thickness direction of the calibration filter membrane 40, the first flow-through hole 313a is circular. When the deposition space 31a is closed, the calibration filter membrane 40 is sandwiched between the confining ring and the second housing 312, and the deposition area 41 is positioned opposite to the first flow-through hole 313a. Thus, through the blocking effect of the confining ring 313, the second aerosol passes through the first flow-through hole 313a and enters the calibration filter membrane 40. The confining ring and the second housing 312 clamp the calibration filter membrane 40, fixing and sealing it. The shape of the first flow-through hole 313a restricts the shape of the deposition area 41 to be circular.

[0159] The diameter of the first flow passage can be 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, etc.

[0160] For example, the second container 21 includes a mask. When the deposition space 31a is closed, the mask is located upstream of the deposition region 41 along the aerosol flow direction. The mask has a second flow-through hole that extends through the thickness direction of the calibration filter membrane 40. In a projection plane perpendicular to the thickness direction of the calibration filter membrane 40, the second flow-through hole is circular. The deposition region 41 is positioned opposite to the second flow-through hole. The shape of the second flow-through hole restricts the shape of the deposition region 41 to be circular.

[0161] In some embodiments, the second container 21 includes an elastic sealing ring 314, which is disposed around the open edge of the first cavity. When the deposition space 31a is closed, the elastic sealing ring 314 is sealed and fitted to one of the second housing 312 and the calibration filter membrane 40, thereby sealing the deposition area 41.

[0162] The elastic sealing ring 314 is made of elastic materials such as rubber and silicone.

[0163] In some embodiments, the manufacturing apparatus further includes a first temperature and humidity sensor 90, which is in communication with the deposition space 31a.

[0164] Thus, the first temperature and humidity data can be measured by the first temperature and humidity sensor 90.

[0165] In some embodiments, the first temperature and humidity sensor 90 is connected to the upstream space 31aa.

[0166] It is understandable that residual radionuclides will remain in the exhaust gas flow after passing through the calibrated filter membrane 40.

[0167] In some embodiments, the manufacturing apparatus further includes a second temperature and humidity sensor 91, which is connected to the processing space 21a.

[0168] Thus, the temperature and humidity data within the processing space 21a can be measured using the second temperature and humidity sensor 91.

[0169] In some embodiments, a flow controller 92 is provided at the outlet of the downstream space 31ab to control the flow rate of the aerosol and maintain a stable flow rate.

[0170] In some embodiments, see Figure 2 The manufacturing apparatus also includes a filtration unit 70, which is connected to the downstream space 31ab and is used to collect aerosol particles.

[0171] In this way, the filter unit 70 can adsorb radionuclides that are not adsorbed in the exhaust gas flow formed after passing through the calibration filter membrane 40, reducing the risk of radionuclides leaking to the outside of the manufacturing device.

[0172] Understandably, the filtration capacity of filter unit 70 is determined based on the radioactivity of the final allowable exhaust airflow. In some embodiments, filter unit 70 has a filtration efficiency of not less than 99.97% for particles of 0.3 μm.

[0173] In some embodiments, see Figure 2The manufacturing apparatus also includes a discharge unit; the discharge unit includes a discharge pipe 80 and a first fan, the discharge pipe 80 connecting the outlet of the filter unit 70 to the outside of the manufacturing apparatus, and the first fan driving the gas inside the discharge pipe 80.

[0174] Thus, the filtered exhaust gas can be discharged to the outside of the manufacturing device through the discharge pipe 80, so as to achieve the purpose of regulating the air pressure inside the manufacturing device.

[0175] In some embodiments, the discharge pipe 80 is equipped with a first check valve to reduce the risk of external airflow backflow into the manufacturing apparatus.

[0176] In some embodiments, see Figure 2 The manufacturing apparatus also includes an emission unit; the emission unit includes a circulation pipe 81 and a second fan, the circulation pipe 81 connecting the outlet of the filter unit 70 to at least one of the storage chamber 11a and the processing space 21a, and the second fan driving the gas in the circulation pipe 81.

[0177] In this way, at least a portion of the filtered exhaust gas can be returned to at least one of the storage chamber 11a and the processing space 21a in order to regulate the gas pressure of at least one of the storage chamber 11a and the processing space 21a and achieve the purpose of controlling the aerosol flow rate.

[0178] In some embodiments, the circulation pipe 81 is provided with a second check valve to reduce the risk that aerosols from at least one of the storage chamber 11a and the processing space 21a may enter the circulation pipe 81 and be directly discharged from the manufacturing apparatus.

[0179] In some embodiments, see Figure 2 The emission unit includes an emission duct 80, a first fan, a circulation duct 81, and a second fan, in order to control the emission airflow to be discharged outside the manufacturing apparatus or into the interior of at least one of the storage chamber 11a and the processing space 21a as needed, thereby helping to maintain the stability of aerosol flow within the manufacturing apparatus.

[0180] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, and improvements made within the spirit and scope of this application are included within the scope of protection of this application.

Claims

1. An apparatus for manufacturing a calibration source for a radioactive monitoring instrument, used to fabricate a calibration filter membrane into a calibration source, characterized in that, include: An aerosol generating unit includes a first container and an atomizing component. The first container is provided with a storage chamber, and the atomizing component is used to atomize a radioactive standard solution in the storage chamber to form an aerosol. An aerosol treatment unit includes a second container, the second container having a treatment space, the treatment space being connected to the storage cavity to allow aerosols to enter the treatment space; The calibration source manufacturing unit includes a sealing assembly and has an openable and closable deposition space that is connected to the processing space. At least a portion of the calibration filter membrane is detachably disposed within the deposition space, which divides the deposition space into an upstream space and a downstream space, the upstream space being connected to the processing space.

2. The manufacturing apparatus according to claim 1, characterized in that, The manufacturing apparatus includes a first conduit connecting the storage cavity and the processing space, at least a portion of which extends vertically.

3. The manufacturing apparatus according to claim 1, characterized in that, The second container also includes a confluence space located below and connected to the processing space.

4. The manufacturing apparatus according to claim 1, characterized in that, The inner wall of the processing space is covered with a hydrophobic layer.

5. The manufacturing apparatus according to claim 1, characterized in that, The manufacturing apparatus further includes a second pipe and a particle size spectrometer. The second pipe connects the upstream space and the processing space, and the particle size spectrometer is used to acquire particle size distribution data of aerosols entering the upstream space through the second pipe.

6. The manufacturing apparatus according to claim 5, characterized in that, The manufacturing apparatus further includes a detection pipeline, both ends of which are selectively connected to or closed to the second pipeline, and the particle size spectrometer is connected to the detection pipeline.

7. The manufacturing apparatus according to claim 1, characterized in that, The calibration source manufacturing unit also includes a switching mechanism and a measurement station. The measurement station is equipped with an activity measuring device. The switching mechanism is used to drive the calibration filter membrane in the deposition space to move to the measurement station so that the activity measuring device can detect the activity of the calibration filter membrane.

8. The manufacturing apparatus according to claim 1, characterized in that, The manufacturing apparatus further includes a first temperature and humidity sensor, which is connected to the deposition space.

9. The manufacturing apparatus according to claim 1, characterized in that, The manufacturing apparatus further includes a filtration unit that is connected to the downstream space and is used to collect aerosol particles.

10. The manufacturing apparatus according to claim 9, characterized in that, The manufacturing apparatus also includes an emission unit; The discharge unit includes a discharge pipe and a first fan. The discharge pipe connects the outlet of the filter unit to the outside of the manufacturing device, and the first fan is used to drive the gas in the discharge pipe. And / or, the emission unit includes a circulation duct and a second fan, the circulation duct connecting the outlet of the filter unit to at least one of the storage chamber and the processing space, and the second fan driving the gas within the circulation duct.

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