Device and method for testing filtering efficiency of aerosol or nuclide generated in fused salt

Abstract

The invention relates to a filtering efficiency testing device and method for aerosol or nuclide generated in fused salt. The filtering efficiency testing device comprises a gas source, a first flow meter, a second flow meter, a temperature controller, an aerosol generating device, a ventilation pipeline, an upstream sampling device, a filter to be tested, a downstream sampling device and a tail gas treatment device. The filtering efficiency testing device can be used for effectively collecting aerosols with different particle size distribution ranges, different morphologies and different concentrations; the analysis test of the filtering efficiency of a filtering material or a filter on specific aerosol / nuclide can be realized; meanwhile, the filtering efficiency testing method can be used for simulating aerosol generated in the fused salt under different atmosphere and temperature conditions and simulating evaporation forms and components of different nuclides in the fused salt under specific conditions, has the characteristics of high sampling efficiency, accurate content testing and the like, and is accurate and reliable in testing result.

Description

Technical Field

[0001] The present application relates to the field of detection technology, and in particular to a device and method for testing the filtration efficiency of aerosols or nuclides generated in molten salt. Background Art

[0002] In a molten salt reactor, aerosols and gaseous radionuclides are generated from the primary coolant and migrate into the blanket gas. In order to reduce the safety hazards caused by blanket gas leakage and reduce the pollutant content in the gaseous effluent, it is necessary to remove the aerosols and radionuclides in the blanket gas so that the pollutant concentration in the blanket gas and exhaust gas system is within the safety limit to ensure radiation safety.

[0003] However, the aerosols and radionuclides in the cover gas of molten salt reactors exist in various forms and the gas temperature is high. It is difficult to sample the radionuclides and analyze the purification effect using traditional analysis methods.

[0004] The existing filtration efficiency detection methods mainly include the following: (1) Standard GB / T 6165-2008 stipulates the aerosol filtration test and analysis method for high-efficiency air filters and filter materials. Its characteristics are that it provides three test methods: sodium flame method, oil mist method and counting method. The filtration efficiency of the filter material or filter is analyzed by the specified aerosol generation and sampling test before and after the filter. However, this generation method does not involve the generation of aerosols in molten salt, nor does it include a test and analysis method for aerosol filtration efficiency at high temperature and for specific nuclides. (2) A patent discloses an aerosol filtration efficiency detection system and method. Its characteristics are that it designs a purification efficiency analysis test method for aerosols in high-temperature steam, which solves the problem of inaccurate testing of traditional particle counters and other devices under such conditions due to condensation water flushing. This method is mainly aimed at aerosol filtration testing in a water vapor environment, and does not set up a proprietary generation and collection test method for specific nuclides under molten salt conditions. It is not suitable for aerosol filtration testing in molten salt. (3) A patent discloses a device and method for evaluating the removal effect of air purification membranes on nano-aerosols. The device and method are characterized in that a stable nano-aerosol can be formed by ultrasonically atomizing a nano-particle solution. The stand and the generating device are convenient. The nano-particle absorption liquid is used to absorb and enrich the aerosol. The concentration and particle size distribution of 100nm aerosol can be quickly and accurately obtained using single-particle inductively coupled plasma mass spectrometry, or nano-particle tracking analysis, or ultraviolet absorption spectroscopy, which solves the technical defect that the existing gas particle measurement technology (laser dust particle counting method) cannot measure nano-level (below 100nm) aerosols. This method does not involve the analysis and test method of aerosol filtration efficiency in high-temperature steam. (4) Another patent discloses an online measurement device with a calibration function for aerosols with a temperature of up to 200°C, a pressure of up to 1Mpa, and a steam concentration share between 0-95%. The device is characterized in that an online test and calibration method for aerosols under high temperature, high pressure and water vapor conditions in nuclear power plants is proposed. This method is quite different from the generation device, collection and measurement methods of the present technology, and cannot simulate the aerosols generated in molten salts or realize the filtration efficiency test of specific nuclides. Summary of the invention

[0005] Based on this, it is necessary to provide a device and method for testing the filtration efficiency of aerosols or nuclides generated in molten salt, which has high sampling efficiency and accurate and reliable test results.

[0006] The technical solution of this application is as follows:

[0007] The present invention provides a device for testing the filtration efficiency of aerosols or nuclides generated in molten salt, comprising an air source, a first flow meter, a second flow meter, a temperature controller, an aerosol generating device, a ventilation duct, an upstream sampling device, a filter to be tested, a downstream sampling device and an exhaust gas treatment device;

[0008] The gas source is communicated with the inlet ends of the first flowmeter and the second flowmeter respectively, the outlet end of the first flowmeter is communicated with the temperature controller; the outlet end of the second flowmeter is connected to the aerosol generating device; the temperature controller is communicated with the ventilation duct, the ventilation duct is simultaneously communicated with the upstream sampling device and the filter to be tested, and the filter to be tested is simultaneously communicated with the downstream sampling device and the exhaust gas treatment device.

[0009] In one embodiment, the aerosol generating device includes a tubular furnace, a check valve and an injection tube;

[0010] The tubular furnace is communicated with the outlet end of the second flow meter; the check valve is communicated with the tubular furnace; the inlet end of the injection pipe is communicated with the check valve; the outlet end of the injection pipe is connected to the inlet end of the ventilation duct.

[0011] In one of the embodiments, the upstream sampling device includes an upstream sampler, a third flow meter, a compressed air pump, and an exhaust pipeline;

[0012] The ventilation duct is communicated with an upstream sampler; the upstream sampler is communicated with a third flow meter; the third flow meter is communicated with a compressed air pump; the compressed air pump is communicated with an inlet end of an exhaust pipeline; and the outlet end of the exhaust pipeline is communicated with a filter to be tested.

[0013] In one of the embodiments, the downstream sampling device includes a downstream sampler, a fourth flow meter, a compressed air pump, and an exhaust line;

[0014] The filter to be tested is communicated with the downstream sampler; the downstream sampler is communicated with the fourth flowmeter; the fourth flowmeter is communicated with the compressed air pump; the compressed air pump is communicated with the inlet end of the exhaust pipeline, and the outlet end of the exhaust pipeline is communicated with the exhaust gas treatment device.

[0015] In one embodiment, the upstream sampler and the downstream sampler both include a monitoring filter membrane and an absorption liquid.

[0016] In one embodiment, the monitoring filter membrane includes a high-efficiency glass fiber filter membrane.

[0017] In one embodiment, the absorption liquid includes one or more of nitric acid, hydrochloric acid or sodium hydroxide.

[0018] A second aspect of the present invention provides a method for testing the filtration efficiency of aerosols or nuclides generated in molten salt, comprising the following steps:

[0019] Providing a filtration efficiency test device for aerosols or nuclides generated in molten salt as described above;

[0020] Introduce carrier gas to replace the pipeline gas, and adjust the gas temperature in the ventilation duct to the preset temperature through the temperature controller;

[0021] Adjust the second flowmeter to a preset flow rate, start the molten salt aerosol generating device, generate aerosol / nuclide by heating the alloy material and pass it into the filter to be tested through the ventilation duct, and sample the gas entering the filter to be tested and the gas filtered by the filter to be tested through the upstream sampling device and the downstream sampling device respectively;

[0022] Dissolve the samples in the upstream sampling device and the downstream sampling device respectively, and test the content of aerosol or nuclide in the samples respectively;

[0023] Calculate the purification coefficient E of the filter to be tested according to the formula shown below:

[0024] ;

[0025] Among them, A0 and A1 are the contents of the aerosol or nuclide to be analyzed in the monitoring filter membrane and the absorption liquid in the upstream sampling device, respectively;

[0026] a0 and a1 are the contents of the aerosol or nuclide to be analyzed in the monitoring filter membrane and the absorption liquid in the downstream sampling device, respectively.

[0027] In one embodiment, the reagent used to dissolve the sample includes one or more of hydrochloric acid, nitric acid or sodium hydroxide solution.

[0028] In one embodiment, the carrier gas comprises one or more of hydrogen, helium or water vapor; and / or

[0029] The alloy material includes one or more of lead-bismuth alloy, tellurium and other element doped lead-bismuth alloy, irradiated lead-bismuth alloy or sodium.

[0030] Compared with the prior art, this application has the following beneficial effects:

[0031] The present application provides a device and method for testing the filtration efficiency of aerosols or nuclides generated in molten salt. The filtration efficiency testing device can effectively collect aerosols with different particle size distribution ranges, different morphologies and different concentrations; it can realize the analysis and testing of the filtration efficiency of filter materials or filters for specific aerosols / nuclide; at the same time, the filtration efficiency testing method can simulate the aerosols generated in molten salt under different atmospheres and temperature conditions, and simulate the evaporation forms and components of different nuclides in the molten salt under specific conditions. It has the characteristics of high sampling efficiency and accurate content testing, and the test results are accurate and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0033] Figure 1 Schematic diagram of the test device described in this application.

[0034] Description of reference numerals:

[0035] 100. Test device; 110. Gas source; 121. First flow meter; 122. Second flow meter; 130. Temperature controller; 140. Aerosol generating device; 141. Tubular furnace; 142. Check valve; 143. Injection pipe; 150. Ventilation duct; 160. Upstream sampling device; 161. Upstream sampler; 162. Third flow meter; 163. Compressed air pump; 164. Exhaust pipeline; 170. Filter to be tested; 180. Downstream sampling device; 181. Downstream sampler; 182. Fourth flow meter; 183. Compressed air pump; 184. Exhaust pipeline; 190. Exhaust treatment device. DETAILED DESCRIPTION

[0036] In order to facilitate the understanding of the present application, the present application will be described more comprehensively with reference to the relevant drawings. The drawings provide preferred embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive.)

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0038] Unless otherwise specified or incompatible herewith, the terms and phrases used herein shall have the following meanings:

[0039] The percentage content involved in the present invention, unless otherwise specified, refers to mass percentage for solid-liquid mixing and solid-solid mixing, and refers to volume percentage for liquid-liquid mixing.

[0040] As used herein, "one or more" refers to any one, any two, or any two or more of the listed items.

[0041] Herein, the optional scope of "and / or", "or / and", and "and / or" includes any one of two or more relevant listed items, and also includes any and all combinations of the relevant listed items, wherein said any and all combinations include any two relevant listed items, any more relevant listed items, or a combination of all relevant listed items. (It should be noted that when at least three items are connected by at least two conjunctions selected from "and / or", "or / and", and "and / or", it should be understood that in the present application, the technical solution undoubtedly includes technical solutions that are all connected by "logical AND", and also undoubtedly includes technical solutions that are all connected by "logical OR". For example, "A and / or B" includes three parallel solutions of A, B and A+B. For another example, the technical solution of "A, and / or, B, and / or, C, and / or, D" includes any one of A, B, C, and D (that is, technical solutions that are all connected by "logical OR"), and also includes any and all combinations of A, B, C, and D, that is, a combination of any two or any three of A, B, C, and D, and also includes a combination of four items of A, B, C, and D (that is, a technical solution that is all connected by "logical AND").)

[0042] Herein, "further", "further", "particularly" and the like are used for descriptive purposes to indicate differences in content, but should not be construed as limiting the scope of protection of this application.

[0043] Herein, "first aspect", "second aspect", "third aspect", "fourth aspect", etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or quantity, nor can they be understood as implicitly indicating the importance or quantity of the indicated technical features. In addition, "first", "second", "third", "fourth", etc. only serve the purpose of non-exhaustive enumeration and description, and it should be understood that they do not constitute a closed limitation on quantity. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. In the description of the present application, the meaning of "several" is at least one, such as one, two, etc., unless otherwise clearly and specifically defined.

[0044] In this application, when it comes to numerical ranges, unless otherwise specified, the above numerical ranges are deemed to be continuous and include the minimum and maximum values ​​of the range, as well as each value between such minimum and maximum values. Further, when a range refers to an integer, each integer between the minimum and maximum values ​​of the range is included. In addition, when multiple ranges are provided to describe features or characteristics, the ranges can be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges included therein.

[0045] Only some numerical ranges are specifically disclosed herein. However, any lower limit can be combined with any upper limit to form an undefined range; and any lower limit can be combined with other lower limits to form an undefined range, and any upper limit can be combined with any other upper limit to form an undefined range. In addition, each separately disclosed point or single value itself can be combined with any other point or single value as a lower limit or upper limit or with other lower limits or upper limits to form an undefined range. The use of numerical ranges represented by endpoints includes all numbers within the range and any range within the range, for example, 1 to 5 includes 1, 1.1, 1.3, 1.5, 2, 2.75, 3, 3.80, 4 and 5, etc.

[0046] The percentage contents involved in this application, unless otherwise specified, refer to mass percentage for solid-liquid mixing and solid-solid mixing, and refer to volume percentage for liquid-liquid mixing.

[0047] The percentage concentrations mentioned in this application, unless otherwise specified, refer to the final concentration, which refers to the percentage of the added component in the system after the addition of the component.

[0048] The temperature parameters in this application, unless otherwise specified, allow both constant temperature treatment and treatment within a certain temperature range. The constant temperature treatment allows the temperature to fluctuate within the accuracy range controlled by the instrument. Fluctuations within the range of ±5°C, ±2°C, ±1°C, ±0.5°C, ±0.4°C, ±0.3°C, ±0.2°C, ±0.1°C are allowed. Normal temperature or room temperature in this application refers to no temperature control operation, generally 4°C~35°C, preferably 20°C±5°C.

[0049] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0050] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0051] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0052] The technicians of this application have found through a lot of research that aerosols / nuclides can be generated by heating relevant alloys in a specific atmosphere, and the particle size and particle morphology of aerosols / nuclides generated by molten salt under specific working conditions can be simulated. Through this generation method, the simulation of aerosols generated in molten salt under different temperatures, carrier gases and other conditions can be realized, and the filtering effect of filter materials or filters on aerosols in molten salt can be more realistically reflected, which can solve the problem of the difference in particle size and particle morphology between aerosols generated by ultrasonic atomization drying and vaporization-condensation oil and gas generation and aerosols in molten salt. At the same time, this application also collects aerosols in carrier gas by monitoring filter membranes and absorption liquids, and can collect aerosols of all particle size ranges, with the characteristics of wide sampling particle size range, high sampling rate, and no limit on sampling concentration. This test method can simulate the migration and capture process of specific nuclides in alloys in carrier gas, and can be used to determine the filtration efficiency of filters or filter membranes for specific nuclides.

[0053] refer to Figure 1 As shown, the present invention provides a device 100 for testing the filtration efficiency of aerosols or nuclides generated in molten salt, including a gas source 110, a first flow meter 121, a second flow meter 122, a temperature controller 130, an aerosol generating device 140, a ventilation duct 150, an upstream sampling device 160, a filter to be tested 170, a downstream sampling device 180 and an exhaust gas treatment device 190.

[0054] The gas source 110 is communicated with the inlet ends of the first flowmeter 121 and the second flowmeter 122 respectively, and the outlet end of the first flowmeter 121 is communicated with the temperature controller 130; the outlet end of the second flowmeter 122 is connected to the aerosol generating device 140; the temperature controller 130 is communicated with the ventilation duct 150, and the ventilation duct 150 is also communicated with the upstream sampling device 160 and the filter to be tested 170, and the filter to be tested 170 is also communicated with the downstream sampling device 180 and the exhaust gas treatment device 190.

[0055] The aerosol generating device 140 includes a tubular furnace 141, a check valve 142 and an injection pipe 143; the tubular furnace 141 is connected to the outlet end of the second flow meter 122; the check valve 142 is connected to the tubular furnace 141; the inlet end of the injection pipe 143 is connected to the check valve 142; the outlet end of the injection pipe is connected to the inlet end of the ventilation duct.

[0056] The upstream sampling device 160 includes an upstream sampler 161, a third flowmeter 162, a compressed air pump 163 and an exhaust pipe 164; the ventilation duct 150 is communicated with the upstream sampler 161; the upstream sampler 161 is communicated with the third flowmeter 162; the third flowmeter 162 is communicated with the compressed air pump 163; the compressed air pump 163 is communicated with the inlet end of the exhaust pipe 164; the outlet end of the exhaust pipe 164 is communicated with the filter 170 to be tested.

[0057] The downstream sampling device 180 includes a downstream sampler 181, a fourth flowmeter 182, a compressed air pump 183 and an exhaust pipeline 184; the filter to be tested 170 is communicated with the downstream sampler 171; the downstream sampler 171 is communicated with the fourth flowmeter 182; the fourth flowmeter 182 is communicated with the compressed air pump 173; the compressed air pump 173 is communicated with the inlet end of the exhaust pipeline 174, and the outlet end of the exhaust pipeline 174 is communicated with the exhaust gas treatment device 190.

[0058] The main test process of this application is as follows: the carrier gas (pure Ar, Ar+H2, Ar+H2O, etc.) controls the gas flow rate through a flow meter, and the carrier gas temperature is controlled by a gas temperature controller in the ventilation duct. The molten salt aerosol generator is generated by heating the alloy in a tubular furnace and injected into the ventilation duct by carrier gas purging. Sampling devices are respectively set upstream and downstream of the filter or filter material to be tested, and the filtration efficiency of the filter or filter material to be tested is calculated based on the test results of the upstream and downstream aerosol or nuclide content. The sampling device consists of a sampler, a flow meter and a compressed air pump. The sampler includes a monitoring filter membrane and an absorption liquid, and the aerosol or nuclide in the main pipeline is completely collected by the monitoring filter membrane and the absorption liquid in the sampler. The monitoring filter membrane selects a filter membrane with excellent filtering effect on the aerosol, including a high-efficiency glass fiber filter membrane, etc., and the absorption liquid selects a solution that can dissolve the aerosol or nuclide to be tested, including nitric acid, hydrochloric acid and sodium hydroxide, etc. The sampled carrier gas is refluxed to the ventilation duct through a flow meter and a compressed air pump. In addition, the testing method of the present application can be combined with a high temperature resistant filter membrane to realize the sampling and filtration efficiency analysis of aerosols in a high temperature environment.

[0059] In some examples, the upstream sampler 160 and the downstream sampler 180 include a monitoring filter and an absorption liquid.

[0060] In some of the examples, the monitoring filter membranes include high-efficiency glass fiber filter membranes.

[0061] In some examples, the absorption liquid includes one or more of nitric acid, hydrochloric acid or sodium hydroxide.

[0062] A second aspect of the present invention provides a method for testing the filtration efficiency of aerosols or nuclides generated in molten salt, comprising the following steps:

[0063] Providing a filtration efficiency test device 100 for aerosols or nuclides generated in molten salt as described above;

[0064] The carrier gas is introduced to replace the pipeline gas, and the temperature of the gas in the ventilation duct 150 is adjusted to a preset temperature by the temperature controller 130;

[0065] The second flow meter 122 is adjusted to a preset flow rate, and the molten salt aerosol generating device 140 is started to generate aerosol / nuclide by heating the alloy material and pass it into the filter to be tested 170 through the ventilation duct 150, and the gas entering the filter to be tested 170 and the gas filtered by the filter to be tested 170 are sampled respectively through the upstream sampling device 160 and the downstream sampling device 180;

[0066] Dissolving the samples in the upstream sampling device 160 and the downstream sampling device 170 respectively, and testing the contents of aerosols / nuclides in the samples respectively;

[0067] Calculate the purification coefficient E of the filter to be tested according to the formula shown below:

[0068] ;

[0069] Wherein, A0 and A1 are the contents of the aerosol / nuclide to be analyzed in the monitoring filter membrane and the absorption liquid in the upstream sampling device 160, respectively;

[0070] a0 and a1 are the contents of the aerosol or nuclide to be analyzed in the monitoring filter membrane and the absorption liquid in the downstream sampling device 170, respectively.

[0071] In some of these examples, the reagents used to dissolve the upstream sampling device 160 and the downstream sampling device 170 include one or more of hydrochloric acid, nitric acid, or sodium hydroxide solution.

[0072] In some examples, the carrier gas includes one or more of hydrogen, helium, or water vapor.

[0073] In some of the examples, the alloy material includes one or more of lead-bismuth alloy, lead-bismuth alloy doped with tellurium and other elements, irradiated lead-bismuth alloy, or sodium.

[0074] In some of the examples, the method for testing the filtration efficiency of aerosols or nuclides generated in the molten salt includes the following steps:

[0075] (1) Loop start-up. Place the alloy material (lead-bismuth alloy, tellurium and other element doped lead-bismuth alloy, irradiated lead-bismuth alloy, sodium, etc.) in a crucible and push it into the constant temperature zone of the tube furnace. Figure 1 The process shown connects the loop, starts the fume hood or glove box, and starts the loop again after the pressure in the fume hood or glove box stabilizes. The pipeline gas is replaced by the first flow meter 121 and the second flow meter 122, and the gas temperature in the ventilation duct is adjusted to a preset temperature by the gas temperature controller 130.

[0076] (2) Loop sampling. The second flow meter 122 is adjusted to a preset flow rate, and the tube furnace heating program is started. Aerosol is generated by heating the alloy material and injected into the ventilation duct 150. The aerosol in the aerosol generator 140 is mixed in the ventilation duct 150 and then passed into the filter. Sampling devices are set before and after the filter to sample the gas before and after the filter.

[0077] (3) Loop stop. After the loop sampling is completed, the third flowmeter 162 and the fourth flowmeter 182 are closed in sequence, the heating of the aerosol generating device 140 is stopped and the second flowmeter 122 is closed, the exhaust gas treatment device 190 is disconnected and the first flowmeter 121 is closed.

[0078] (4) Content test. Dissolve the sample on the sampling filter membrane (using hydrochloric acid, nitric acid, sodium hydroxide solution, etc.), and use ICP-OES, ICP-AES, ICP-MS, and activity test (liquid scintillation, α spectrometer, γ spectrometer, etc.) to test the content of the nuclides to be analyzed in the sampling filter membrane and the sampling absorption liquid. Calculate the filtration efficiency of the filter or filter membrane based on the test results.

[0079] (5) Calculation of purification coefficient. The calculation method of the purification coefficient E of the filter device to be tested is shown in the following formula.

[0080]

[0081] Among them, A0 and A1 are the contents of the nuclides to be measured in the sampling filter membrane and the sampling absorption liquid in the upstream sampling device respectively;

[0082] a0 and a1 are the contents of the nuclides to be measured in the sampling filter membrane and the sampling absorption liquid in the downstream sampling device, respectively;

[0083] D and d are the sampling flow rates of the upstream and downstream sampling devices, respectively.

[0084] The following is further described in conjunction with specific embodiments. The raw materials involved in the following specific embodiments, unless otherwise specified, can all be commercially available; the instruments used, unless otherwise specified, can all be commercially available; the processes involved, unless otherwise specified, are all routinely selected by those skilled in the art.

[0085] The following are specific embodiments.

[0086] Example 1

[0087] Please refer to Figure 1 As shown, this embodiment provides a filtration efficiency testing device 100 for aerosols or nuclides generated in molten salt, including a gas source 110, a first flow meter 121, a second flow meter 122, a temperature controller 130, an aerosol generating device 140, a ventilation duct 150, an upstream sampling device 160, a filter to be tested 170, a downstream sampling device 180 and an exhaust gas treatment device 190.

[0088] The gas source 110 is communicated with the inlet ends of the first flowmeter 121 and the second flowmeter 122 respectively, and the outlet end of the first flowmeter 121 is communicated with the temperature controller 130; the outlet end of the second flowmeter 122 is connected to the aerosol generating device 140; the temperature controller 130 is communicated with the ventilation duct 150, and the ventilation duct 150 is communicated with the upstream sampling device 160 and the filter to be tested 170 respectively, and the filter to be tested 170 is communicated with the downstream sampling device 180 and the exhaust gas treatment device 190 respectively.

[0089] The aerosol generating device 140 includes a tubular furnace 141, a check valve 142 and an injection pipe 143; the tubular furnace 141 is connected to the outlet end of the second flow meter 122; the check valve 142 is connected to the tubular furnace 141; the inlet end of the injection pipe 143 is connected to the check valve 142; the outlet end of the injection pipe is connected to the inlet end of the ventilation duct.

[0090] The upstream sampling device 160 includes an upstream sampler 161, a third flowmeter 162, a compressed air pump 163 and an exhaust pipe 164; the ventilation duct 150 is communicated with the upstream sampler 161; the upstream sampler 161 is communicated with the third flowmeter 162; the third flowmeter 162 is communicated with the compressed air pump 163; the compressed air pump 163 is communicated with the inlet end of the exhaust pipe 164; the outlet end of the exhaust pipe 164 is communicated with the filter 170 to be tested.

[0091] The downstream sampling device 180 includes a downstream sampler 181, a fourth flowmeter 182, a compressed air pump 183 and an exhaust pipeline 184; the filter to be tested 170 is communicated with the downstream sampler 171; the downstream sampler 171 is communicated with the fourth flowmeter 182; the fourth flowmeter 182 is communicated with the compressed air pump 173; the compressed air pump 173 is communicated with the inlet end of the exhaust pipeline 174, and the outlet end of the exhaust pipeline 174 is communicated with the exhaust gas treatment device 190.

[0092] Example 2

[0093] This example tests the filtration efficiency of Po-210 in irradiated lead-bismuth alloy under high temperature atmosphere conditions. The main test steps are as follows:

[0094] (1) Loop start-up. Place the irradiated lead-bismuth alloy sample in a crucible and push it into the constant temperature zone of the tube furnace. Figure 1 The process shown connects the loop, and the loop is started after the pressure in the glove box is stable. The pipeline gas is replaced by the first flow meter and the second flow meter, and the gas temperature in the ventilation duct is adjusted to 300°C by the gas temperature controller.

[0095] (2) Loop sampling. Adjust the second flow meter to 1l / min, set the tubular furnace to 300°C, generate aerosol by heating the irradiated alloy and inject it into the ventilation duct. Set the first flow meter to 9l / min. The aerosol in the aerosol generator is mixed in the ventilation duct and then passed into the filter. The sampler uses a high-temperature resistant glass fiber filter membrane or a stainless steel wire mesh as the monitoring filter membrane, and nitric acid as the absorption liquid. Sampling devices are set upstream and downstream of the filter to sample the gas upstream and downstream of the filter, and the upstream and downstream sampling flow rates are set to 100ml / min. In particular, in order to ensure the sampling effect, multi-layer filter screens and multi-stage absorption liquids can be selected for series sampling.

[0096] (3) Loop stop. After the loop sampling is completed, the upstream and downstream sampling devices are stopped and cut off in turn, and the heating of the aerosol generating device is stopped and the channel is cut off.

[0097] (4) Content test. Dissolve the sample on the sampling filter membrane and use an alpha spectrometer or liquid scintillation meter to test the radioactivity of Po-210 in the sampling filter membrane and the sampling absorption liquid.

[0098] (5) Calculation of purification coefficient. The calculation method of the purification coefficient E of the filter device to be tested is as follows:

[0099]

[0100] Among them, A0 and A1 are the activities of Po-210 in the sampling filter membrane and the sampling absorption liquid in the upstream sampling device, respectively.

[0101] a0 and a1 are the activities of Po-210 in the sampling filter and the sampling absorption liquid in the downstream sampling device, respectively.

[0102] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0103] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims, and the description may be used to interpret the content of the claims.

Claims

1. A device for testing the filtration efficiency of aerosols or nuclides generated in molten salt, characterized in that: It includes an air source, a first flow meter, a second flow meter, a temperature controller, an aerosol generating device, a ventilation duct, an upstream sampling device, a filter to be tested, a downstream sampling device and an exhaust gas treatment device; The gas source is communicated with the inlet ends of the first flowmeter and the second flowmeter respectively, the outlet end of the first flowmeter is communicated with the temperature controller; the outlet end of the second flowmeter is connected to the aerosol generating device; the temperature controller is communicated with the ventilation duct, the ventilation duct is simultaneously communicated with the upstream sampling device and the filter to be tested, and the filter to be tested is simultaneously communicated with the downstream sampling device and the exhaust gas treatment device.

2. The filtration efficiency testing device for aerosol or nuclide generated in molten salt according to claim 1, characterized in that: The aerosol generating device comprises a tubular furnace, a check valve and an injection pipe; The tubular furnace is communicated with the outlet end of the second flow meter; the check valve is communicated with the tubular furnace; the inlet end of the injection pipe is communicated with the check valve; the outlet end of the injection pipe is connected to the inlet end of the ventilation duct.

3. The filtration efficiency testing device for aerosol or nuclide generated in molten salt according to claim 1, characterized in that: The upstream sampling device includes an upstream sampler, a third flow meter, a compressed air pump and an exhaust pipeline; The ventilation duct is communicated with an upstream sampler; the upstream sampler is communicated with a third flow meter; the third flow meter is communicated with a compressed air pump; the compressed air pump is communicated with an inlet end of an exhaust pipeline; and the outlet end of the exhaust pipeline is communicated with a filter to be tested.

4. The filtration efficiency testing device for aerosol or nuclide generated in molten salt according to claim 1, characterized in that: The downstream sampling device includes a downstream sampler, a fourth flow meter, a compressed air pump and an exhaust pipeline; The filter to be tested is communicated with the downstream sampler; the downstream sampler is communicated with the fourth flowmeter; the fourth flowmeter is communicated with the compressed air pump; the compressed air pump is communicated with the inlet end of the exhaust pipeline, and the outlet end of the exhaust pipeline is communicated with the exhaust gas treatment device.

5. The filtration efficiency testing device for aerosol or nuclide generated in molten salt according to claim 1, characterized in that: The upstream sampler and the downstream sampler both include a monitoring filter membrane and an absorption liquid.

6. The filtration efficiency testing device for aerosol or nuclide generated in molten salt according to claim 5, characterized in that: The monitoring filter membrane comprises a high-efficiency glass fiber filter membrane.

7. The filtration efficiency testing device for aerosol or nuclide generated in molten salt according to claim 5, characterized in that: The absorption liquid includes one or more of nitric acid, hydrochloric acid or sodium hydroxide.

8. A method for testing the filtration efficiency of aerosols or nuclides generated in molten salt, characterized in that: The following steps are involved: Providing a filtration efficiency test device for aerosol or nuclide generated in molten salt as described in any one of claims 1 to 7; Introduce carrier gas to replace the pipeline gas, and adjust the gas temperature in the ventilation duct to the preset temperature through the temperature controller; Adjust the second flowmeter to a preset flow rate, start the molten salt aerosol generating device, generate aerosol / nuclide by heating the alloy material and pass it into the filter to be tested through the ventilation duct, and sample the gas entering the filter to be tested and the gas filtered by the filter to be tested through the upstream sampling device and the downstream sampling device respectively; Dissolve the samples in the upstream sampling device and the downstream sampling device respectively, and test the content of aerosol or nuclide in the samples respectively; Calculate the purification coefficient E of the filter to be tested according to the formula shown below: ； Among them, A0 and A1 are the contents of the aerosol or nuclide to be analyzed in the monitoring filter membrane and the absorption liquid in the upstream sampling device, respectively; a0 and a1 are the contents of the aerosol or nuclide to be analyzed in the monitoring filter membrane and the absorption liquid in the downstream sampling device, respectively.

9. The method for testing the filtration efficiency of aerosols or nuclides generated in molten salt according to claim 8, characterized in that: The reagent used to dissolve the sample includes one or more of hydrochloric acid, nitric acid or sodium hydroxide solution.

10. The method for testing the filtration efficiency of aerosols or nuclides generated in molten salt according to claim 8, characterized in that: The carrier gas comprises one or more of hydrogen, helium or water vapor; and / or The alloy material includes one or more of lead-bismuth alloy, tellurium and other element doped lead-bismuth alloy, irradiated lead-bismuth alloy or sodium.

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