Power pipe structure for Po-210 protection device and performance test method thereof

Abstract

The invention discloses a power pipe structure for a Po-210 protection device and a performance testing method thereof, and relates to the technical field of radioactive waste gas treatment.The power pipe structure comprises a pipe body, openings are formed in the two ends of the pipe body, pipe caps are installed at the openings, and sealing gaskets are installed at the joints of the pipe caps and the pipe body; a plurality of sieve plates are mounted in the pipe body and divide the pipe body into a plurality of cavities, and filter materials are mounted in the cavities. The power pipe structure can be used for testing the performance of various candidate Po trapping materials and optimizing and verifying the structure and the performance of a subsequent protective filter box, guides the type selection of a Po-210 filter material and the design and the optimization of a Po-210 personal protection device, provides support for personnel protection in the processes of running, overhauling and the like of a subsequent lead-bismuth fast reactor, and has a good application prospect. According to the performance testing method, the filtering efficiency of the power pipe structure can be accurately measured, and then the filtering performance of the Po-210 protection device can be conveniently detected.

Description

Technical Field

[0001] The invention relates to the technical field of radioactive waste gas treatment, and in particular to a power tube structure for a Po-210 protection device and a performance testing method thereof. Background Art

[0002] Polonium-210 is an extremely toxic radioactive nuclide that easily forms a radioactive aerosol of polonium-210 with a half-life of 138.4 days. If it enters the body, it will destroy the cell structure of human tissues and organs, damage DNA and cause cell death. There is a possibility of polonium-210 leakage in specific nuclear facilities (such as lead-bismuth fast reactors, etc.), and the leaked polonium-210 may have a serious impact on workers and the environment. Especially in high-temperature environments such as blanket gas, the relative concentration of polonium-210 is high. In normal operating conditions, there is also a risk of Po leakage in the ambient gas. When the monitoring equipment does not detect whether there is a radioactive risk, or when a medium- and low-concentration radioactive risk is detected, it is necessary to wear Po-210 protection equipment for medium- and low-concentration scenarios for regular inspection and maintenance. Therefore, it is necessary to develop a Po protection device that has a capture and adsorption effect on Po-210-containing gases in radioactive scenarios.

[0003] Patent CN109166641B discloses a low-level radioactive waste gas treatment system in a lead-bismuth pile, the system includes a waste gas inlet for inputting radioactive waste gas to be treated, a filtering unit for filtering aerosols and particulate matter in the waste gas, a compression temporary storage unit for pressurizing and temporarily storing the waste gas after filtering, a retention unit for retaining and decaying the waste gas pressurized and output by the compression temporary storage unit, and a radioactive monitoring unit for collecting waste gas at multiple locations in the system and performing waste gas radioactivity concentration analysis, the waste gas inlet, the filtering unit, the compression temporary storage unit, and the retention unit are connected in sequence through pipelines. Among them, the filtering unit includes a first filter and a second filter, the waste gas inlet, the first filter, the second filter, and the compression temporary storage unit are connected in sequence through pipelines, the first filter is used for preliminary filtering of aerosols and particulate matter in the waste gas input by the waste gas inlet; the second filter is used for secondary filtering of aerosols and particulate matter in the waste gas after preliminary filtration.

[0004] The currently disclosed methods for treating radioactive waste gas usually adopt a filtering method, as disclosed in the above patent, using a filter to filter aerosols and particulate matter in the waste gas, wherein the filtering performance of the filter material used in the filter is extremely important to the final treatment effect of the radioactive waste gas, and due to the special physical and chemical properties of Po-210, it is necessary to test the protective performance of the filter material. However, there is no report on the testing of the protective performance of the filter material used in the Po-210 protection device. Summary of the invention

[0005] Based on the problem that there is currently a lack of detection of the protective performance of filter materials used in Po-210 protective devices, the purpose of the present invention is to provide a power tube structure for Po-210 protective devices and a performance testing method thereof, wherein the power tube structure can perform performance tests on a variety of candidate Po capture materials, as well as the structure and performance optimization verification of subsequent protective filter boxes, guide the selection of Po-210 filter materials and the design and optimization of Po-210 personal protective devices, and provide support for personnel protection during the operation and maintenance of subsequent lead-bismuth fast reactors.

[0006] The present invention is achieved through the following technical solutions:

[0007] In a first aspect, the present application provides a power tube structure for a Po-210 protective device, comprising a tube body, both ends of the tube body are provided with openings, and tube caps are installed at the openings, and a sealing gasket is installed at the connection between the tube cap and the tube body; a plurality of sieve plates are installed in the tube body, and the plurality of sieve plates divide the tube body into a plurality of cavities, and filter materials are installed in the cavities.

[0008] When assembling the power tube structure, firstly, the filter material is filled into the tube body and separated by the sieve plate, and then the tube cap and the tube body are sealed by the sealing gasket and screws.

[0009] Furthermore, the tube cap has a cone structure.

[0010] Furthermore, the inner diameter of the large end of the tube cap is 2cm to 4cm, and the length is 3cm to 12cm; the inner diameter of the small end of the tube cap is 1mm to 50mm, and the length is 0.2cm to 2cm.

[0011] Among them, the inner diameter of the large mouth end of the conical structure tube cap can be 2cm, 2.5cm, 3cm, 3.5cm, 4cm, and any size in the range of 2cm to 4cm. It can be determined according to the inner diameter of the tube body, so that the tube cap and the tube body can achieve a sealed connection.

[0012] Among them, the length of the large end of the tube cap with a conical structure can be 3cm, 3.5cm, 4cm, 4.5cm, 5cm, 5.5cm, 6cm, 6.5cm, 7cm, 7.5cm, 8cm, 8.5cm, 9cm, 9.5cm, 10cm, 10.5cm, 11cm, 11.5cm, and any size within the range of 3cm to 12cm, which can be determined according to actual needs.

[0013] Among them, the inner diameter of the small mouth end of the tube cap with a cone structure can be 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, 21mm, 22mm, 23mm, 24mm, 25mm, 26mm, 27mm, 28mm, 29mm, 30mm, 31mm, 32mm, 33mm, 34mm, 35mm, 36mm, 37mm, 38mm, 39mm, 40mm, 41mm, 42mm, 43mm, 44mm, 45mm, 46mm, 47mm, 48mm, 49mm, 50mm, and any size within the range of 1mm to 50mm, which can be determined according to actual needs.

[0014] Among them, the length of the small end of the tube cap with a conical structure can be 0.2cm, 0.3cm, 0.4cm, 0.5cm, 0.6cm, 0.7cm, 0.8cm, 0.9cm, 1.0cm, 1.1cm, 1.2cm, 1.3cm, 1.4cm, 1.5cm, 1.6cm, 1.7cm, 1.8cm, 1.9cm, 2cm, and any size within the range of 0.2cm to 2cm, which can be determined according to actual needs.

[0015] Furthermore, the total weight of the filter material installed in the tube body is 10g to 200g.

[0016] Among them, the total weight of the filter material installed in the tube body can be 10g, 20g, 30g, 40g, 50g, 60g, 70g, 80g, 90g, 100g, 110g, 120g, 130g, 140g, 150g, 160g, 170g, 180g, 190g, 200g, and any value within the range of 10g to 200g, which can be determined according to actual needs.

[0017] The power tube structure of the present invention can be used for Po-210 protection devices, and can be used for performance testing of various candidate Po capture materials, as well as for structural and performance optimization verification of subsequent protection filter boxes, to guide the selection of Po-210 filter materials and the design and optimization of Po-210 personal protection devices, and to provide support for personnel protection during the operation and maintenance of subsequent lead-bismuth fast reactors.

[0018] In a second aspect, the present application provides a Po-210 protection device, comprising the above-mentioned power tube structure.

[0019] In a third aspect, the present application provides a performance detection device for a power tube structure of a Po-210 protective device, comprising a power tube structure installed on a gas pipeline, wherein two gas branch pipelines connected in parallel are arranged at the front and rear ends of the power tube structure, a first gas washing bottle and a first rotor flowmeter are connected to the gas branch pipeline at one end of the air inlet of the power tube structure, and a second gas washing bottle and a second rotor flowmeter are connected to the gas branch pipeline at one end of the air outlet of the power tube structure.

[0020] Furthermore, the first gas washing bottle and the second gas washing bottle both contain nitric acid solution.

[0021] In a fourth aspect, the present application provides a performance testing method for a power tube structure, which is performed using the above-mentioned performance testing device and includes the following steps:

[0022] Install the Po capture filter material in the power pipe;

[0023] Inject nitric acid solution into the first gas washing bottle and the second gas washing bottle, and close the first rotor flowmeter and the second rotor flowmeter;

[0024] Perform air tightness test on the entire detection device and maintain pressure until the pressure value changes by no more than 5kPa-20kPa; wherein, the pressure maintaining time may be 5min to 30min;

[0025] Among them, the holding time can be 5min, 6min, 7min, 8min, 9min, 10min, 11min, 12min, 13min, 14min, 15min, 16min, 17min, 18min, 19min, 20min, 21min, 22min, 23min, 24min, 25min, 26min, 27min, 28min, 29min, 30min, or any value within the range of 5min to 30min, which can be determined according to actual conditions.

[0026] The Po-containing aerosol is introduced into the performance detection device through the gas pipeline, and the Po-containing aerosol passes through the power tube structure, the first gas washing bottle, and the second gas washing bottle;

[0027] Set the ventilation time according to the protection time required by the Po-210 protection device, and stop ventilation after the preset time is reached;

[0028] Take out the same volume of solution from the first washing bottle and the second washing bottle, add Po-209 tracer respectively, and analyze the activity concentration of Po-210 to obtain the capture efficiency of Po capture filter material;

[0029] The filter materials in the power tube structure were removed layer by layer, the alpha radioactivity of the interlayer filter materials was measured respectively, the filtration efficiency of the single layer filter materials was calculated, and the total filtration efficiency of the device was calculated accordingly, verifying the filtration efficiency obtained based on the gas washing bottle mentioned above;

[0030] Based on the Po-210 activity concentration calculated by the second scrubbing bottle and referring to the Po-210 limit in the air, the protection time is calculated. And under the protection time, the concentration of Po-210 after scrubbing is measured to further verify the accuracy of the protection time.

[0031] Among them, the air inlet of the gas pipeline provides air intake for the entire performance detection device, so that the gas containing Po aerosol in medium and low concentrations enters the performance detection device. A device that can generate Po aerosol is connected to the air inlet of the gas pipeline. The filter material arranged in the power tube structure is used to specifically adsorb Po, which can achieve efficient adsorption and retention of Po. The gas adsorbed by the filter material is discharged from the air outlet of the pipeline. After the discharged gas is tested, if further filtering treatment is required, it needs to be further filtered before being discharged. The first washing bottle and the second washing bottle are respectively used to wash the gas before and after passing through the power tube structure, so that the Po in the gas phase is transferred to the liquid phase. The solution components in the first washing bottle and the second washing bottle are both high-concentration nitric acid solutions. The first rotor flowmeter is used to control the air intake flow of the first washing bottle, and the second rotor flowmeter is used to control the air intake flow of the second washing bottle.

[0032] Furthermore, the flow rate of Po aerosol at the air inlet of the gas pipeline is controlled at 1SLPM-30SLPM, with an accuracy better than or equal to ±0.5FS.

[0033] Among them, the flow rate of Po aerosol at the air inlet of the gas pipeline can be 1SLPM, 2SLPM, 3SLPM, 4SLPM, 5SLPM, 6SLPM, 7SLPM, 8SLPM, 9SLPM, 10SLPM, 11SLPM, 12SLPM, 13SLPM, 14SLPM, 15SLPM, 16SLPM, 17SLPM, 18SLPM, 19SLPM, 20SLPM, 21SLPM, 22SLPM, 23SLPM, 24SLPM, 25SLPM, 26SLPM, 27SLPM, 28SLPM, 29SLPM, 30SLPM, or any value within the range of 1SLPM-30SLPM, which can be determined according to actual needs.

[0034] Furthermore, the activity concentration of Po in the Po aerosol at the air inlet of the gas pipeline is 11.1 Bq / m 3 -111.0Bq / m 3 .

[0035] Among them, the activity concentration of Po in the Po aerosol at the air inlet of the gas pipeline can be 11.1 Bq / m 3 、15.0Bq / m 3 、20.0Bq / m 3 、25.0Bq / m 3 、30.0Bq / m 3 、35.0Bq / m 3 、40.0Bq / m 3 45.0Bq / m 3 、50.0Bq / m 3 、55.0Bq / m 3 、60.0Bq / m 3 、65.0Bq / m 3 、70.0Bq / m 3 、75.0Bq / m 3 、80.0Bq / m 3 、85.0Bq / m 3 、90.0Bq / m 3 、95.0Bq / m 3 、100.0Bq / m 3 、105.0Bq / m 3 、111.0Bq / m 3 , or 11.1 Bq / m 3 -111.0Bq / m 3 Any value within the range can be determined according to actual needs.

[0036] Further, the concentration of nitric acid used in the first washing bottle and the second washing bottle is 1 mol / L-10 mol / L. The volume of the first washing bottle and the second washing bottle can be 100 mL-1000 mL, and 20 mL-300 mL of nitric acid is placed in the bottle.

[0037] Among them, the concentration of nitric acid used in the first washing bottle and the second washing bottle can be 1mol / L, 2mol / L, 3mol / L, 4mol / L, 5mol / L, 6mol / L, 7mol / L, 8mol / L, 9mol / L, 10mol / L, or any value within the range of 1mol / L-10mol / L, which can be determined according to actual needs.

[0038] Among them, the volume of the first washing bottle and the second washing bottle can be 100mL, 150mL, 200mL, 250mL, 300mL, 350mL, 400mL, 450mL, 500mL, 550mL, 600mL, 650mL, 700mL, 750mL, 800mL, 850mL, 900mL, 950mL, 1000mL, or any value within the range of 100mL to 1000mL, which can be determined according to actual needs.

[0039] Among them, the volume of nitric acid placed in the bottle can be 20mL, 30mL, 40mL, 50mL, 60mL, 70mL, 80mL, 90mL, 100mL, 110mL, 120mL, 130mL, 140mL, 150mL, 160mL, 170mL, 180mL, 190mL, 200mL, 210mL, 220mL, 230mL, 240mL, 250mL, 260mL, 270mL, 280mL, 290mL, 300mL, or any value within the range of 20mL to 300mL, which can be determined according to actual needs.

[0040] Furthermore, the maximum range of the first rotor flowmeter and the second rotor flowmeter is not less than 0.5 L / min, and the flow rate is set to 0.1 L / min to 0.5 L / min during use.

[0041] Among them, the flow rate set during the use of the first rotor flowmeter and the second rotor flowmeter can be 0.1L / min, 0.2L / min, 0.3L / min, 0.4L / min, 0.5L / min, or any value within the range of 0.1L / min to 0.5L / min, which can be determined according to actual needs.

[0042] Furthermore, during the detection, 0.1 Bq-10 Bq Po-209 tracer was added to the first washing bottle and the second washing bottle respectively.

[0043] Among them, during detection, the Po-209 tracer added to the first washing bottle and the second washing bottle can be 0.1Bq, 1Bq, 2Bq, 3Bq, 4Bq, 5Bq, 6Bq, 7Bq, 8Bq, 9Bq, 10Bq, or any value within the range of 0.1Bq-10Bq, which can be determined according to actual needs.

[0044] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0045] (1) The power tube structure of the present invention can test the performance of various candidate Po capture materials, optimize and verify the structure and performance of subsequent protective filter boxes, guide the selection of Po-210 filter materials and the design and optimization of Po-210 personal protective equipment, and provide support for personnel protection during the operation and maintenance of subsequent lead-bismuth fast reactors.

[0046] (2) The power tube structure of the present invention has good scalability and can simulate the core component of the protective device - the protective filter box.

[0047] (3) The Po-210 performance test method of the present invention is based on the overall filtering effect of the gas washing bottle and the cumulative filtering efficiency of the filter material in the power tube structure. The combination of the two can accurately measure the filtering efficiency of the power tube structure, thereby facilitating the detection of the filtering performance of the Po-210 protective device. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other relevant drawings can be obtained based on these drawings without creative work. In the drawings:

[0049] Figure 1 It is a schematic structural diagram of a power tube structure used for a Po-210 protection device in the present invention;

[0050] Figure 2 for Figure 1 A magnified view of middle;

[0051] Figure 3 It is a structural schematic diagram of a tube cap with a cone structure in the present invention;

[0052] Figure 4 It is a structural schematic diagram of the performance detection device of the power tube structure in the present invention. Description of the drawings:

[0054] 01- pipe cap, 02- pipe body, 03- sieve plate, 04- filter material, 05- sealing gasket, 06- second rotor flowmeter, 07- power tube structure, 08- gas pipeline, 09- first gas washing bottle, 10- first rotor flowmeter, 11- second gas washing bottle. DETAILED DESCRIPTION

[0055] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0056] The following detailed description specifically discloses the implementation method of the power tube structure and performance test method for the Po-210 protective device of the present application with appropriate reference to the accompanying drawings. However, there may be cases where unnecessary detailed descriptions are omitted. For example, there are cases where detailed descriptions of well-known matters and repeated descriptions of actually the same structure are omitted. This is to avoid the following description from becoming unnecessarily lengthy and to facilitate the understanding of those skilled in the art. In addition, the drawings and the following description are provided for those skilled in the art to fully understand the present application and are not intended to limit the subject matter described in the claims.

[0057] The "range" disclosed in the present application is defined in the form of a lower limit and an upper limit, and a given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundaries of a particular range. The range defined in this way can include or exclude end values, and can be combined arbitrarily, that is, any lower limit can be combined with any upper limit to form a range. If there is no special explanation, the "including" and "comprising" mentioned in the present application represent open-ended or closed-ended. For example, the "including" and "comprising" can represent that other substances not listed can also be included or included, or only listed substances can be included or included.

[0058] In the present application, the terms "front", "rear", "left", "right", "up", "down", "vertical", "horizontal", "high", "low", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the scope of protection of the present invention. The terms "first", "second", etc. used in the present invention are only used to distinguish the corresponding components for the sake of clarity of description, and are not intended to limit any order or emphasize importance, etc. In addition, the term "connected" used in this article, unless otherwise specified, can be directly connected or indirectly connected via other components.

[0059] Therefore, the following detailed description of the embodiments of the present invention is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0060] Example 1

[0061] like Figures 1 to 3 As shown, this embodiment provides a power tube structure for a Po-210 protective device, including a tube body 02, both ends of the tube body 02 are provided with openings, and the openings are installed with cone-shaped tube caps 01, and a sealing gasket 05 is installed at the connection between the cone-shaped tube cap 01 and the tube body 02; a plurality of sieve plates 03 are installed in the tube body 02, and the plurality of sieve plates 03 divide the tube body 02 into a plurality of cavities, and filter materials 04 are installed in the cavities.

[0062] Specifically, the inner diameter of the large end of the tube cap 01 of the cone structure is 2 cm to 4 cm, and the length is 3 cm to 12 cm; the inner diameter of the small end of the tube cap 01 is 1 mm to 50 mm, and the length is 0.2 cm to 2 cm.

[0063] Specifically, the total weight of the filter material 04 installed in the tube body 02 is 10 g to 200 g.

[0064] The power tube structure can be used for Po-210 protection devices, and can be used to test the performance of a variety of candidate Po capture materials, as well as the structure and performance optimization verification of subsequent protective filter boxes, guide the selection of Po-210 filter material 04 and the design and optimization of Po-210 personal protection devices, and provide support for personnel protection during the operation and maintenance of subsequent lead-bismuth fast reactors.

[0065] Example 2

[0066] like Figures 1 to 4 As shown, this embodiment provides a performance detection device for a power tube structure of a Po-210 protective device, including a power tube structure 07 installed on a gas pipeline 08, two gas branch pipelines connected in parallel are arranged at the front and rear ends of the power tube structure 07, a first gas washing bottle 09 and a first rotor flowmeter 10 are connected to the gas branch pipeline at one end of the air inlet of the power tube structure 07, and a second gas washing bottle 11 and a second rotor flowmeter 06 are connected to the gas branch pipeline at one end of the air outlet of the power tube structure 07.

[0067] The power tube structure 07 in this embodiment is the power tube structure 07 in Example 1, specifically: it includes a tube body 02, both ends of the tube body 02 are provided with openings, and the openings are installed with a cone-shaped tube cap 01, and a sealing gasket 05 is installed at the connection between the cone-shaped tube cap 01 and the tube body 02; a plurality of sieve plates 03 are installed in the tube body 02, and the plurality of sieve plates 03 divide the tube body 02 into a plurality of cavities, and filter materials 04 are installed in the cavities. The inner diameter of the large end of the cone-shaped tube cap 01 is 2cm to 4cm, and the length is 3cm to 12cm; the inner diameter of the small end of the tube cap 01 is 1mm to 50mm, and the length is 0.2cm to 2cm. The total weight of the filter material 04 installed in the tube body 02 is 10g to 200g.

[0068] Specifically, the first washing bottle 09 and the second washing bottle 11 are both filled with nitric acid solution; the concentration of nitric acid is 1mol / L-10mol / L; the volume of the first washing bottle 09 and the second washing bottle 11 can be 100mL-1000mL, and 20mL-300mL of nitric acid is placed in the bottles.

[0069] The air inlet of the gas pipeline 08 provides air intake for the entire performance detection device, so that the gas containing Po aerosol in medium and low concentrations enters the performance detection device. A device that can generate Po aerosol is connected at the air inlet of the gas pipeline 08. The filter material 04 set in the power tube structure 07 is used to specifically adsorb Po, which can achieve efficient adsorption and retention of Po. The gas adsorbed by the filter material 04 is discharged from the air outlet of the pipeline. After the discharged gas is tested, if further filtering treatment is required, it needs to be further filtered before being discharged. The first washing bottle 09 and the second washing bottle 11 are respectively used to wash the gas before and after passing through the power tube structure 07, so that Po in the gas phase is transferred to the liquid phase. The solution components in the first washing bottle 09 and the second washing bottle 11 are both high-concentration nitric acid solutions. The first rotor flowmeter 10 is used to control the intake flow of the first washing bottle 09, and the second rotor flowmeter 06 is used to control the intake flow of the second washing bottle 11.

[0070] The performance detection device is based on the power tube structure 07 in Example 1 and the connection structure of the first gas washing bottle 09 and the second gas washing bottle 11 connected to the gas pipeline 08. The combination of the two can accurately measure the filtration efficiency of the power tube structure 07, thereby facilitating the detection of the filtration performance of the Po-210 protective device.

[0071] Example 3

[0072] like Figures 1 to 4 As shown, this embodiment provides a performance detection method for a power tube structure of a Po-210 protective device, and the performance detection device in Example 2 is used for detection. The specific detection steps are:

[0073] S1. Install the Po collection filter material 04 in the tube body 02 of the power tube structure 07;

[0074] S2, inject 100mL-1000mL of 1mol / L-10mol / L nitric acid solution into the first washing bottle 09 and the second washing bottle 11, and close the first rotor flowmeter 10 and the second rotor flowmeter 06;

[0075] S3. Perform air tightness test on the entire detection device and maintain pressure for 5 to 30 minutes until the pressure value changes by no more than 5 kPa-20 kPa;

[0076] S4, open the Po-210 aerosol generating device, the first rotor flowmeter 10, the second rotor flowmeter 06 and the corresponding pipeline valves, etc., so that the gas containing Po aerosol flows through the power pipe structure 07, the first washing bottle 09, and the second washing bottle 11;

[0077] Specifically, the protection time of the protective filter box for medium and low concentration scenes is 30 minutes to 120 minutes, and the filtration performance test with the same protection time is carried out based on the detection device;

[0078] Specifically, the maximum range of the first rotor flowmeter 10 and the second rotor flowmeter 06 is not less than 0.5 L / min, and the flow rate is set to 0.1 L / min to 0.5 L / min during use;

[0079] Specifically, the activity concentration of Po in the Po aerosol at the air inlet of gas pipeline 08 is 11.1 Bq / m3-111.0 Bq / m3;

[0080] Specifically, the concentration of nitric acid used in the first washing bottle 09 and the second washing bottle 11 is 1 mol / L-10 mol / L, the volume of the first washing bottle 09 and the second washing bottle 11 is 100 mL-1000 mL, and 20 mL-300 mL of nitric acid is placed in the bottle;

[0081] S5. Set the ventilation time according to the protection time required by the Po-210 protection device. After reaching the predetermined protection time, close the corresponding aerosol generating device, the first rotor flowmeter 10, the second rotor flowmeter 06 and the corresponding pipeline valves;

[0082] S6, take out 50 mL of solution from the first washing bottle 09 and the second washing bottle 11 respectively, add 0.1 Bq-10 Bq Po-209 tracer respectively, and analyze the activity concentration of Po-210 to obtain the capture efficiency of Po capture filter material 04;

[0083] S7, taking out the filter material 04 in the power tube structure 07 in layers, measuring the α radioactivity of each layer of the filter material 04, calculating the filtration efficiency of the single layer of the filter material 04, and calculating the total filtration efficiency of the device from this, to verify the filtration efficiency obtained based on the gas washing bottle;

[0084] S8. Based on the Po-210 activity concentration calculated by the second scrubbing bottle 11 and referring to the Po-210 limit in the air, the protection time is calculated; and under the protection time, the concentration of Po-210 after scrubbing is measured to further verify the accuracy of the protection time.

[0085] The performance detection method is based on the connection mode of the power tube structure 07 and the first and second gas washing bottles 09 and 11 connected in the gas pipeline 08. The combination of the two can accurately measure the filtering efficiency of the power tube structure 07, thereby facilitating the detection of the filtering performance of the Po-210 protective device.

[0086] Experimental Case 1

[0087] The performance testing method in Example 3 is used to test the protective performance of the power tube structure in the performance testing device in Example 2. The structure of the testing device includes a power tube structure 07 installed on a gas pipeline 08. Two gas branch pipelines connected in parallel are arranged at the front and rear ends of the power tube structure 07. The gas branch pipeline at the air inlet end of the power tube structure 07 is connected to a first gas washing bottle 09 and a first rotor flowmeter 10. The gas branch pipeline at the air outlet end of the power tube structure 07 is connected to a second gas washing bottle 11 and a second rotor flowmeter 06.

[0088] The power tube structure 07 includes a tube body 02, both ends of which are provided with openings, and a cone-shaped tube cap 01 is installed at the opening, and a sealing gasket 05 is installed at the connection between the cone-shaped tube cap 01 and the tube body 02; a plurality of sieve plates 03 are installed in the tube body 02, and the plurality of sieve plates 03 divide the tube body 02 into six cavities, and a filter material 04 is installed in each cavity.

[0089] Specifically, the Po capture filter material used in the power tube structure is a modified carbon-based material, which is endowed with the ability to specifically adsorb Po by impregnating metals such as copper, silver, platinum, nickel and zinc on the surface or inside of the activated carbon material. In this test case, a modified carbon-based material with copper impregnated on the surface of the activated carbon material is specifically used.

[0090] Specifically, the inner diameter of the large end of the tube cap 01 of the cone structure is 3 cm, and the length is 8 cm; the inner diameter of the small end of the tube cap 01 is 20 mm, and the length is 1 cm.

[0091] Specifically, the total weight of the filter material 04 installed in the tube body 02 is 100 g.

[0092] The specific detection method is:

[0093] S1. Install the Po collection filter material 04 in the tube body 02 of the power tube structure 07;

[0094] S2, inject 300mL of 5mol / L nitric acid solution into the first washing bottle 09 and the second washing bottle 11, and close the first rotor flowmeter 10 and the second rotor flowmeter 06;

[0095] S3. Perform air tightness test on the entire testing device and maintain the pressure for 10 minutes until the pressure value changes by no more than 10 kPa;

[0096] S4, open the Po-210 aerosol generating device, the first rotor flowmeter 10, the second rotor flowmeter 06 and the corresponding pipeline valves, etc., so that the gas containing Po aerosol flows through the power pipe structure 07, the first washing bottle 09, and the second washing bottle 11;

[0097] Among them, taking the protection time of the protective filter box for medium and low concentration scenes as 30 minutes as an example, based on the detection device, the filtration performance test with equivalent protection time is carried out. The designed standard tank diameter is 105mm and the air volume is 30L / min. According to the diameter D (unit: mm) of the power tube, the air intake volume Q1 of the power tube can be calculated as: Q1 = 30*(D / 105) 2 ; Specifically, when the power tube diameter D is 20mm, the power tube air intake volume Q1 is 1.1L / min. Among them, the flow rate Q2 of the first rotor flowmeter 10 and the second rotor flowmeter 06 is set to 0.1L / min~0.5L / min; therefore, the flow rate Q of the low-concentration Po-containing aerosol air inlet is: Q=Q1+Q2; when the flow rate Q2 of the rotor flowmeter is set to 0.2L / min, and the power tube diameter D is 20mm, the flow rate Q of the Po-containing aerosol air inlet is 1.3L / min.

[0098] S5. According to the protection time required by the Po-210 protection device, the ventilation time is set to 30 minutes. After the predetermined protection time is reached, the corresponding aerosol generating device, the first rotor flowmeter 10, the second rotor flowmeter 06 and the corresponding pipeline valves are closed;

[0099] S6, take out 50 mL of solution from the first washing bottle 09 and the second washing bottle 11 respectively, add 0.5 Bq Po-209 tracer respectively, analyze the activity concentration of Po-210, and then obtain the capture efficiency of Po capture filter material 04;

[0100] S7, taking out the filter material 04 in the power tube structure 07 in layers, measuring the α radioactivity of each layer of the filter material 04, calculating the filtration efficiency of the single layer of the filter material 04, and calculating the total filtration efficiency of the device from this, to verify the filtration efficiency obtained based on the gas washing bottle;

[0101] S8. Based on the Po-210 activity concentration calculated by the second scrubbing bottle 11 and referring to the Po-210 limit in the air, the protection time is calculated; and under the protection time, the concentration of Po-210 after scrubbing is measured to further verify the accuracy of the protection time.

[0102] After testing, the Po-210 count in the first washing bottle 09 was 14452 cpm, and the Po-210 count in the second washing bottle 11 was 10 cpm. After calculating the change in Po-210 content before and after washing, the filtration efficiency was determined to be 99.93%.

[0103] The Po-210 content of the six layers of filter material is 564cpm, 87cpm, 22cpm, 7cpm, 1cpm, and 0.5cpm respectively. By calculating the Po-210 counts in the first and last layers of filter material near the air inlet of the power tube, the filtration efficiency is determined to be 99.91%.

[0104] Based on the test results of the gas washing bottle and the filter material, it is confirmed that the filtration efficiency of the power tube and the filter material for Po-210 can reach 99.9%. The power tube and the filter material provided can effectively filter the Po-210 in the air space.

[0105] In the description of this specification, the description with reference to the terms "Example 1", "Example 2", "Example 3", etc. means that the specific features, systems, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, systems, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples without contradiction.

[0106] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that it is still possible to modify the technical solutions described in the aforementioned embodiments, or to replace some or all of the technical features therein by equivalents. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

Claims

1. A power tube structure for a Po-210 protection device, characterized in that: The invention comprises a tube body (02), both ends of the tube body (02) are provided with openings, and tube caps (01) are installed at the openings, and a sealing gasket (05) is installed at the connection between the tube cap (01) and the tube body (02); a plurality of sieve plates (03) are installed in the tube body (02), and the plurality of sieve plates (03) divide the tube body (02) into a plurality of cavities, and filter materials (04) are installed in the cavities.

2. A power tube structure for a Po-210 protection device according to claim 1, characterized in that: The tube cap (01) has a cone structure.

3. A power tube structure for a Po-210 protection device according to claim 2, characterized in that: The inner diameter of the large end of the tube cap (01) is 2 cm to 4 cm, and the length is 3 cm to 12 cm; the inner diameter of the small end of the tube cap (01) is 1 mm to 50 mm, and the length is 0.2 cm to 2 cm.

4. A power tube structure for a Po-210 protection device according to claim 1, characterized in that: The total weight of the filter material (04) installed in the tube body (02) is 10 g to 200 g.

5. A Po-210 protection device, characterized in that: The invention comprises the power tube structure as described in any one of claims 1 to 4.

6. A performance detection device for a power tube structure of a Po-210 protective device according to any one of claims 1 to 4, characterized in that: It comprises a power tube structure (07) installed on a gas pipeline (08), wherein two gas branch pipelines connected in parallel are arranged at the front and rear ends of the power tube structure (07), a first gas washing bottle (09) and a first rotor flowmeter (10) are connected to the gas branch pipeline at one end of the gas inlet of the power tube structure (07), and a second gas washing bottle (11) and a second rotor flowmeter (06) are connected to the gas branch pipeline at one end of the gas outlet of the power tube structure (07).

7. A performance detection device for a power tube structure of a Po-210 protection device according to claim 6, characterized in that: The first gas washing bottle (09) and the second gas washing bottle (11) are both filled with nitric acid solution.

8. A performance testing method for a power tube structure, characterized in that: The method is carried out using the performance detection device according to claim 6 or 7, comprising the following steps: Install the Po capture filter material (04) in the power pipe; Inject nitric acid solution into the first gas washing bottle (09) and the second gas washing bottle (11), and close the first rotor flowmeter (10) and the second rotor flowmeter (06); Conduct air tightness test on the entire testing device and maintain the pressure until the pressure value changes by no more than 5kPa-20kPa; The Po-containing aerosol is introduced into the performance detection device through the gas pipeline (08), and the Po-containing aerosol passes through the power tube structure (07), the first washing bottle (09), and the second washing bottle (11); Set the ventilation time according to the protection time required by the Po-210 protection device, and stop ventilation after the preset time is reached; Taking out the same volume of solution from the first washing bottle (09) and the second washing bottle (11), adding Po-209 tracer respectively, and analyzing the activity concentration of Po-210 to obtain the capture efficiency of the Po capture filter material (04); The filter materials (04) in the power tube structure (07) are taken out in layers, the α radioactivity of the interlayer filter materials (04) is measured respectively, the filtration efficiency of the single-layer filter materials (04) is calculated, and the total filtration efficiency of the device is calculated accordingly, to verify the filtration efficiency obtained based on the gas washing bottle; Based on the Po-210 activity concentration calculated by the second scrubbing bottle (11), the protection time is calculated with reference to the Po-210 limit in the air; and under the protection time, the concentration of Po-210 after scrubbing is measured to further verify the accuracy of the protection time.

9. A performance detection method for a power tube structure according to claim 8, characterized in that: The flow rate of Po aerosol at the air inlet of the gas pipeline (08) is controlled at 1SLPM-30SLPM.

10. A performance detection method for a power tube structure according to claim 8, characterized in that: The activity concentration of Po in the Po aerosol at the air inlet of the gas pipeline (08) is 11.1 Bq / m3-111.0 Bq / m3.

11. A performance detection method for a power tube structure according to claim 8, characterized in that: The concentration of nitric acid used in the first scrubbing bottle (09) and the second scrubbing bottle (11) is 1 mol / L-10 mol / L.

12. A method for detecting the performance of a power tube structure according to claim 8, characterized in that: The maximum range of the first rotor flowmeter (10) and the second rotor flowmeter (06) is not less than 0.5 L / min, and the flow rate is set to 0.1 L / min to 0.5 L / min during use.

13. A performance testing method for a power tube structure according to claim 8, characterized in that: During the detection, 0.1 Bq to 10 Bq of Po-209 tracer is added to the first gas washing bottle (09) and the second gas washing bottle (11) respectively.

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