Device and method for testing water vapor filtering efficiency of filtering piece

Abstract

The invention provides a device and a method for testing the water vapor filtering efficiency of a filtering piece. The device for testing the water vapor filtering efficiency of the filtering piece comprises a compressed air source, a saturated water vapor generating device, a dry and wet air mixing and buffering device, a filtering piece testing clamp device and a system pipeline. The compressed air source is connected with the saturated water vapor generating device and the dry and wet air mixing buffering device. And the saturated water vapor generating device is connected with the dry and wet air mixing buffer device. And the filter test fixture device is connected with the dry and wet air mixing buffer device and is used for mounting and testing the respirator filter so as to calculate the water vapor filtering efficiency by utilizing the water vapor concentration at the front end and the rear end of the respirator filter measured by a built-in sensor. According to the tritiated water vapor filtering performance non-discharge test evaluation device and method suitable for the tritium respiratory protection equipment filtering piece, the technical problem that the tritiated water vapor or water vapor filtering efficiency of an existing respirator filtering piece is difficult to quantitatively test and evaluate is solved.

Description

Technical Field

[0001] This application belongs to the technical field of performance detection and evaluation of respiratory protection equipment filters, and particularly relates to a test device and method for the water vapor filtration efficiency of filters. Background Art

[0002] As a common radioactive isotope in nuclear fuel cycle facilities, tritium can be produced through neutron activation reactions of various nuclides. When tritium is released into the environment, it will form tritides through isotope exchange reactions or oxidation reactions. In a tritium-containing working environment, most of the tritium is dispersed in the air around the site in the form of tritiated water vapor. When workers work in a tritium-containing environment, they will inhale tritiated water vapor during the breathing process, thus causing internal irradiation damage hazards. Therefore, it is necessary to provide reliable tritium respiratory protection equipment for workers in tritium-related sites to reduce the internal irradiation hazards of tritium.

[0003] Testing the filtration efficiency of tritiated water vapor supports the design and verification of the tritium protection effect of filters. However, directly using tritiated water vapor for experimental testing poses a significant risk of radioactive hazards, and at the same time, the price of standard tritiated water is high, with large experimental risks and costs. Except for radioactivity, the physical and chemical properties of tritiated water vapor are basically the same as those of water vapor. Therefore, a non-radioactive alternative test can be carried out using the water vapor filtration efficiency test method. In terms of the test method and device for testing the filtration efficiency of water vapor, there is currently no system device on the market that can be used to test the filtration efficiency of tritiated water vapor or water vapor for respirator filters. In order to quantitatively test and evaluate the water vapor filtration efficiency of respirator filters, it is necessary to develop a test system device for the water vapor filtration efficiency of filters to facilitate the analysis of the water vapor filtration protection effect of respirator filters.

[0004] Due to the lack of reasonable and effective test and evaluation methods and devices, currently, during the actual use of tritium protection respirator filters by on-site workers in nuclear facilities, they usually need to select and match based on usage experience, with a relatively conservative usage duration, and can only indirectly evaluate the tritium protection effect of the filters through the tritium internal irradiation dose evaluation method after the completion of the personnel's work tasks, which is not conducive to the optimization and improvement of the on-site radiation protection level. Summary of the Invention

[0005] In view of this, this application is committed to providing a test device and method for the water vapor filtration efficiency of filters, by setting up a device and method for non-radioactive experimental testing and evaluation of the tritiated water vapor filtration performance suitable for filters of tritium respiratory protection equipment, so as to solve the technical problem that it is difficult to quantitatively test and evaluate the filtration efficiency of tritiated water vapor or water vapor for current respirator filters.

[0006] The first aspect of the present application provides a test device for the water vapor filtration efficiency of a filter element. The test device for the water vapor filtration efficiency of the filter element includes a compressed air source, a saturated water vapor generating device, a dry and wet air mixing and buffering device, a filter element test fixture device with built-in sensors, and a system pipeline. The compressed air source is respectively connected to the air inlet of the saturated water vapor generating device and the dry air inlet interface of the dry and wet air mixing and buffering device, and is used to provide compressed air for the saturated water vapor generating device and the dry and wet air mixing and buffering device. The saturated water vapor generating device is used to generate saturated water vapor by using the compressed air provided by the compressed air source. The outlet of the saturated water vapor generating device is connected to the saturated water vapor inlet interface of the dry and wet air mixing and buffering device. The dry and wet air mixing and buffering device is used to regulate the proportion of dry and wet air by using the compressed air provided by the compressed air source and the saturated water vapor generated by the saturated water vapor generating device, and generate mixed air with the required target humidity. The filter element test fixture device is connected to the mixed air exhaust port of the dry and wet air mixing and buffering device, and is used for the installation test of the respirator filter element to calculate the water vapor filtration efficiency based on the water vapor concentrations at the front and rear ends of the respirator filter element measured by the built-in sensors.

[0007] In a specific embodiment of the present application, the test device for the water vapor filtration efficiency of the filter element further includes a plurality of solenoid valves and a plurality of flow controllers. The solenoid valves are used to control the flow of air in the system pipeline. The flow controllers are used to control the flow rate of air in the system pipeline. The plurality of solenoid valves include a first solenoid valve, a second solenoid valve, a third solenoid valve, a fourth solenoid valve, a fifth solenoid valve, and a sixth solenoid valve. The plurality of flow controllers include a first flow controller and a second flow controller.

[0008] The first solenoid valve and the first flow controller are connected in the circuit between the compressed air source and the dry and wet air mixing and buffering device. The compressed air provided by the compressed air source enters the inside of the dry and wet air mixing and buffering device after passing through the first solenoid valve and the first flow controller.

[0009] The second solenoid valve and the second flow controller are connected in the circuit between the compressed air source and the saturated water vapor generating device. The compressed air provided by the compressed air source enters the inside of the saturated water vapor generating device after passing through the second solenoid valve and the second flow controller.

[0010] The third solenoid valve is connected in the circuit between the saturated water vapor generating device and the dry and wet air mixing and buffering device. The saturated water vapor produced by the saturated water vapor generating device enters the dry and wet air mixing and buffering device after passing through the third solenoid valve.

[0011] The fourth solenoid valve is connected in the circuit between the dry and wet air mixing and buffering device and the filter element test fixture device; the fifth solenoid valve is directly connected to the circuit of the dry and wet air mixing and buffering device and is arranged in parallel with the fourth solenoid valve; the sixth solenoid valve is directly connected to the outlet of the filter element test fixture device.

[0012] In a specific embodiment of the present application, the saturated water vapor generating device includes a water tank main body, a liquid level sensor, a temperature sensor, a heating rod, and an aeration element. A liquid level sensor and a temperature sensor are installed inside the water tank main body. The liquid level sensor is used for controlling the water level inside the water tank main body. The temperature sensor is used for measuring the water temperature inside the water tank main body and for feedback adjustment of the power of the heating rod. Both the heating rod and the aeration element extend from the top to the bottom of the water tank main body. The aeration element is used for generating saturated water vapor after the compressed gas is in full contact with the heated water.

[0013] In a specific embodiment of the present application, the aeration element is made of sponge material.

[0014] In a specific embodiment of the present application, the dry-wet air mixing buffer device includes a first temperature and humidity sensor, a mixed air exhaust port, a buffer tank main body, and a drainage interface. The first temperature and humidity sensor extends from the top of the buffer tank main body to the inside of the buffer tank main body. The mixed air exhaust port is located at the top of the buffer tank main body and is used for discharging the mixed gas. The drainage interface is located at the bottom of the buffer tank main body and is used for discharging the condensed water formed by the saturated water vapor inside the buffer tank main body.

[0015] In a specific embodiment of the present application, the filter element test fixture device includes an upper half fixture, a lower half fixture, and a filter element interface base. The middle mating surfaces of the upper half fixture and the lower half fixture are sealed and connected through a sealing ring and a clamp. A filter element interface base for installing the filter element is also provided on the lower half fixture.

[0016] In a specific embodiment of the present application, the built-in sensors include a dew point sensor and a second temperature and humidity sensor. The second temperature and humidity sensor is installed above the upper half fixture and is used for measuring the temperature and humidity of the air upstream of the filter element. The dew point sensor is installed below the lower half fixture and is used for measuring the humidity of the air downstream of the filter element.

[0017] In a specific embodiment of the present application, the filter element interface base is set as a replaceable filter element interface base.

[0018] In a specific embodiment of the present application, the temperature measurement range of the second temperature and humidity sensor is -50°C to 180°C, and the accuracy is ±0.1°C; the humidity measurement range of the second temperature and humidity sensor is 0 to 100%RH, and the accuracy is 0.8%.

[0019] In a specific embodiment of the present application, the measurement range of the dew point sensor is -70 to 60°C T d , and the accuracy is ±0.1°C T d .

[0020] The second aspect of the present application provides a method for testing the water vapor filtration efficiency of a filter element. The method for testing the water vapor filtration efficiency of the filter element includes: Step 1: Install the breathing apparatus filter element in the filter element test fixture device of the filter element water vapor filtration efficiency test device according to the first aspect of the present application; Step 2: Open the compressed air source. The saturated water vapor generating device uses the compressed air provided by the compressed air source to generate saturated water vapor and supply it to the dry and wet air mixing and buffering device. The dry and wet air mixing and buffering device uses the compressed air provided by the compressed air source and the saturated water vapor generated by the saturated water vapor generating device to adjust the proportion of dry and wet air, and generates mixed air with the required target humidity and flows into the filter element test fixture device; Step 3: The built-in sensor provided in the filter element test fixture device measures the water vapor concentration at the front end and the rear end of the breathing apparatus filter element to calculate the water vapor filtration efficiency.

[0021] The beneficial effects of the technical solution of the present application are as follows: By using the compressed air source to provide compressed air for the saturated water vapor generating device and the dry and wet air mixing and buffering device, the compressed air is a dry and clean air source. On the one hand, this dry and clean air source can purge the system pipeline before the experimental test to discharge the ambient air in the system pipeline and prevent its interference with the test results. In addition, the filter element water vapor filtration efficiency test device system proposed in the embodiment of the present application is easy to operate, has high stability and reliability, solves the problem of testing the water vapor filtration efficiency of the breathing apparatus filter element at the nuclear facility site, can directly provide a quantitative test reference result for the tritiated water vapor filtration efficiency of the breathing apparatus filter element, and the filter element water vapor filtration efficiency test device can greatly reduce the test cost of the tritiated water vapor filtration efficiency of the breathing apparatus filter element and avoid the risk of internal irradiation damage to personnel during the test process. Description of the Drawings

[0022] Figure 1 The figure shows a structural schematic diagram of a filter element water vapor filtration efficiency test device provided by an embodiment of the present application.

[0023] Figure 2 The figure shows a structural schematic diagram of a saturated water vapor generating device provided by an embodiment of the present application.

[0024] Figure 3 The figure shows a structural schematic diagram of a dry and wet air mixing and buffering device provided by an embodiment of the present application.

[0025] Figure 4 The figure shows a structural schematic diagram of a filter element test fixture device provided by an embodiment of the present application.

[0026] Figure 5 The figure shows what is provided by an embodiment of the present application Figure 4Schematic cross-sectional view of the filter element test fixture device shown along N-N.

[0027] In the figure, 1. Compressed air source; 2. Saturated water vapor generation device; 3. Dry and wet air mixing buffer device; 4. Filter element test fixture device; 5. Water tank main body; 6. Liquid level sensor; 7. Temperature sensor; 8. Heating rod; 9. Aeration element; 10. First temperature and humidity sensor; 11. Mixed air exhaust port; 12. Buffer tank main body; 13. Saturated water vapor inlet interface; 14. Drainage interface; 15. Dry air inlet interface; 16. Upper half fixture; 17. Lower half fixture; 18. Dew point sensor; 19. Second temperature and humidity sensor; 20. Filter element interface base; A1. First solenoid valve; A2. Second solenoid valve; A3. Third solenoid valve; A4. Fourth solenoid valve; A5. Fifth solenoid valve; A6. Sixth solenoid valve; B1. First flow controller; B2. Second flow controller. Specific implementation manners

[0028] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0029] At least one embodiment of the present application provides a filter element water vapor filtration efficiency test device, which is applicable to the non-radioactive test and evaluation of the tritiated water vapor filtration performance of the filter element of the tritium breathing protection equipment. As Figure 1 and Figure 3As shown, the test device for the water vapor filtration efficiency of the filter element includes a compressed air source 1, a saturated water vapor generating device 2, a dry and wet air mixing and buffering device 3, a filter element test fixture device 4, and a system pipeline. The compressed air source 1 is respectively connected to the air inlet of the saturated water vapor generating device 2 and the dry air inlet interface 15 of the dry and wet air mixing and buffering device 3, and is used to provide compressed air for the saturated water vapor generating device 2 and the dry and wet air mixing and buffering device 3. The saturated water vapor generating device 2 is used to generate saturated water vapor by using the compressed air provided by the compressed air source 1. The outlet of the saturated water vapor generating device 2 is connected to the saturated water vapor inlet interface 13 of the dry and wet air mixing and buffering device 3. The dry and wet air mixing and buffering device 3 is used to regulate the proportion of dry and wet air by using the compressed air provided by the compressed air source 1 and the saturated water vapor generated by the saturated water vapor generating device 2, and generate mixed air with the required target humidity. The filter element test fixture device 4 is connected to the mixed air exhaust port 11 of the dry and wet air mixing and buffering device 3, and is used for the installation test of the respirator filter element to calculate the water vapor filtration efficiency by using the water vapor concentrations at the front and rear ends of the respirator filter element measured by the built-in sensor.

[0030] It should be noted that the compressed air source 1 can be selected according to actual needs, and the embodiments of the present application do not make specific limitations in this regard. For example, the compressed air source 1 can be a commercially available oil-free silent air pump with a maximum air supply flow rate of 300 L / min and a pressure of 0.7 MPa. The respirator filter element can also be called a tritium respiratory protection equipment filter element.

[0031] According to the technical solution provided by the embodiments of the present application, by using the compressed air source 1 to provide compressed air for the saturated water vapor generating device 2 and the dry and wet air mixing and buffering device 3, the compressed air is a dry and clean air source. On the one hand, this dry and clean air source can purge the system pipeline before the experimental test to discharge the ambient air in the system pipeline and prevent its interference with the test results. In addition, the test device system for the water vapor filtration efficiency of the filter element proposed in the embodiments of the present application is easy to operate, has high stability and reliability, solves the problem of testing the water vapor filtration efficiency of the respirator filter element at the nuclear facility site, can directly provide a quantitative test reference result for the tritiated water vapor filtration efficiency of the respirator filter element, and the test device for the water vapor filtration efficiency of the filter element can greatly reduce the test cost of the tritiated water vapor filtration efficiency of the respirator filter element and avoid the risk of internal irradiation damage to personnel during the test process.

[0032] In at least one embodiment of the present application, the test device for the water vapor filtration efficiency of the filter element further includes a plurality of solenoid valves and a plurality of flow controllers. The solenoid valves are used to control the flow of air in the system pipeline. The flow controllers are used to control the flow rate of air in the system pipeline. The plurality of solenoid valves include a first solenoid valve A1, a second solenoid valve A2, a third solenoid valve A3, a fourth solenoid valve A4, a fifth solenoid valve A5, and a sixth solenoid valve A6. The plurality of flow controllers include a first flow controller B1 and a second flow controller B2.

[0033] The first solenoid valve A1 and the first flow controller B1 are connected in the circuit of the compressed air source 1 and the wet and dry air mixing buffer device 3. The compressed air provided by the compressed air source 1 enters the inside of the wet and dry air mixing buffer device 3 after passing through the first solenoid valve A1 and the first flow controller B1.

[0034] The second solenoid valve A2 and the second flow controller B2 are connected in the circuit of the compressed air source 1 and the saturated water vapor generating device 2. The compressed air provided by the compressed air source 1 enters the inside of the saturated water vapor generating device 2 after passing through the second solenoid valve A2 and the second flow controller B2.

[0035] The third solenoid valve A3 is connected in the circuit of the saturated water vapor generating device 2 and the wet and dry air mixing buffer device 3. The saturated water vapor produced by the saturated water vapor generating device 2 enters the wet and dry air mixing buffer device 3 after passing through the third solenoid valve A3.

[0036] The fourth solenoid valve A4 is connected in the circuit of the wet and dry air mixing buffer device 3 and the filter element test fixture device 4; the fifth solenoid valve A5 is directly connected in the circuit of the wet and dry air mixing buffer device 3 and is arranged in parallel with the fourth solenoid valve A4; the sixth solenoid valve A6 is directly connected to the outlet of the filter element test fixture device 4.

[0037] It should be noted that the fourth solenoid valve A4 is used to control the test air produced by the wet and dry air mixing buffer device 3 to flow into the filter element test fixture device 4.

[0038] In the above embodiments of the present application, by adding a plurality of solenoid valves and using the solenoid valves to control the flow of air in the system pipeline, the non-radioactive test evaluation of the tritiated water vapor filtration performance of the filter element of the tritium respiratory protection equipment under different flow rates is realized. In addition, by adding a plurality of flow controllers and using the flow controllers to control the flow rate of air in the system pipeline, by means of adjusting the mixing ratio of saturated water vapor and dry air for wet and dry premixing, and in combination with the wet and dry air mixing buffer device 3, the stable adjustment of air with different humidities is realized, and the non-radioactive test evaluation of the tritiated water vapor filtration performance of the filter element of the tritium respiratory protection equipment under different flow rates and humidities is realized.

[0039] The saturated steam generating device 2 only needs to be able to realize the function of generating saturated steam by using the compressed air provided by the compressed air source 1. On this basis, the structural composition of the saturated steam generating device 2 is not specifically limited in the embodiments of the present application. Next, the structural composition of the saturated steam generating device 2 will be illustrated by way of specific examples.

[0040] In at least one embodiment of the present application, with reference to Figure 1 and Figure 2 , the saturated steam generating device 2 includes a water tank main body 5, a liquid level sensor 6, a temperature sensor 7, a heating rod 8, and an aeration element 9. The liquid level sensor 6 and the temperature sensor 7 are installed inside the water tank main body 5. The liquid level sensor 6 is used for controlling the water level inside the water tank main body 5. The temperature sensor 7 is used for measuring the water temperature inside the water tank main body 5 and for the feedback regulation of the power of the heating rod 8. Both the heating rod 8 and the aeration element 9 extend from the top to the bottom of the water tank main body 5. The aeration element 9 is used for generating saturated steam after the compressed gas is in full contact with the heated water.

[0041] For example, the water tank main body 5 is made of stainless steel by welding and sealing. For example, high-quality stainless steel material can be selected for the stainless steel. In this way, the water tank main body 5 can be fully sealed to prevent the compressed gas and saturated steam inside the water tank main body 5 from leaking out. In some embodiments, the saturated steam generating device 2 may further include an intake check valve and an inlet and drain valve. The intake check valve and the inlet and drain valve can be used to ensure the smooth replenishment of water and control the non-return of water in the water tank.

[0042] In the above embodiments of the present application, the liquid level sensor 6 is used to control the water level inside the water tank main body 5, which is convenient for timely replenishment and drainage of water. At the same time, the compressed gas can generate saturated steam after being in full contact with the heated water through the aeration element 9. Combining the liquid level sensor 6 and the temperature sensor 7, stable generation control of saturated steam can be achieved.

[0043] In at least one embodiment of the present application, the aeration element 9 is made of sponge material. In this way, the compressed gas flowing into the water tank main body 5 can be in full contact with the water to generate saturated steam.

[0044] In at least one embodiment of the present application, with reference to Figure 1 and Figure 3 , the dry and wet air mixing and buffering device 3 includes a first temperature and humidity sensor 10, a mixed air exhaust port 11, a buffer tank main body 12, and a drainage interface 14. The first temperature and humidity sensor 10 extends from the top of the buffer tank main body 12 to the inside of the buffer tank main body 12. The mixed air exhaust port 11 is located at the top of the buffer tank main body 12 and is used for discharging the mixed gas. The drainage interface 14 is located at the bottom of the buffer tank main body 12 and is used for discharging the condensed water formed by saturated steam inside the buffer tank main body 12.

[0045] For example, the buffer tank body 12 can be welded and sealed with high-quality stainless steel. In this way, the buffer tank body 12 can be fully sealed to prevent the compressed gas inside the buffer tank body 12 from leaking out.

[0046] The volume of the internal cavity of the buffer tank body 12 can be set according to actual needs. For example, the volume of the internal cavity of the buffer tank body 12 is about 0.5 m 3 , and the embodiment of the present application does not specifically limit the volume of the internal cavity of the buffer tank body 12.

[0047] In the above embodiment of the present application, saturated water vapor and compressed air enter the inside of the buffer tank body 12 through the saturated water vapor inlet interface 13 and the dry air inlet interface 15 respectively, and are evenly mixed. The inlet ratio of the two gases is adjusted by the first flow controller B1 and the second flow controller B2 to achieve different humidity premixing control. During the mixing process, the temperature and humidity parameters of the air inside the box are monitored by the first temperature and humidity sensor 10. After reaching the target temperature and humidity, the mixed gas is directly discharged from the mixed air exhaust port 11, and the condensed water formed by the saturated water vapor inside the buffer tank body 12 is discharged through the drain interface 14.

[0048] In at least one embodiment of the present application, refer to Figure 1 , Figure 4 and Figure 5 , the filter element test fixture device 4 includes an upper half fixture 16, a lower half fixture 17, and a filter element interface base 20. The middle mating surfaces of the upper half fixture 16 and the lower half fixture 17 are sealed and connected through a sealing ring and a clamp. The lower half fixture 17 is also provided with a filter element interface base 20 for installing the filter element.

[0049] For example, the upper half fixture 16 and the lower half fixture 17 are made of stainless steel material.

[0050] In at least one embodiment of the present application, the built-in sensors include a dew point sensor 18 and a second temperature and humidity sensor 19. The second temperature and humidity sensor 19 is installed above the upper half fixture 16 for measuring the temperature and humidity of the air upstream of the filter element. The dew point sensor 18 is installed below the lower half fixture 17 for measuring the humidity of the air downstream of the filter element.

[0051] In the above embodiment of the present application, since the water vapor content in the wet air is greatly reduced after being filtered by the filter element, the dew point sensor 18 is installed below the lower half fixture 17. Finally, the upstream temperature and humidity parameters measured by the second temperature and humidity sensor 19 and the downstream temperature and humidity parameters measured by the dew point sensor 18 are converted into water vapor content, and the water vapor filtration efficiency of the filter element is calculated.

[0052] In at least one embodiment of the present application, the filter element interface base 20 is provided as a replaceable filter element interface base. In this way, different interface structure filter element tests can be realized by using the replaceable filter element interface base.

[0053] In at least one embodiment of the present application, the temperature measurement range of the second temperature and humidity sensor 19 is -50°C to 180°C, and the accuracy is ±0.1°C. The humidity measurement range of the second temperature and humidity sensor 19 is 0 to 100%RH, and the accuracy is 0.8%.

[0054] In at least one embodiment of the present application, the measurement range of the dew point sensor 18 is -70 to 60°C T d , and the accuracy is ±0.1°C T d .

[0055] At least one embodiment of the present application also provides a method for testing the water vapor filtration efficiency of a filter element. The method for testing the water vapor filtration efficiency of the filter element calculates the water vapor filtration efficiency of the breathing apparatus filter element by measuring the water vapor concentration at the front end and the back end of the breathing apparatus filter element. The method for testing the water vapor filtration efficiency of the filter element includes the following steps.

[0056] Step 1: Install the breathing apparatus filter element in the filter element test fixture device 4 of the water vapor filtration efficiency test device for a filter element according to any one of the above embodiments of the present application.

[0057] For example, install the breathing apparatus filter element on the filter element interface base 20 in the filter element test fixture device 4, and place the breathing apparatus filter element in the lower half fixture 17, and then install the upper half fixture 16 and the sealing clamp. The sealing clamp is used to clamp the upper half fixture 16 and the lower half fixture 17.

[0058] It should be noted that before the test starts, check whether all components and system pipelines such as the compressed air source 1, the saturated water vapor generating device 2, the dry and wet air mixing buffer device 3, and the filter element test fixture device 4 in the water vapor filtration efficiency test device for a filter element according to any one of the above embodiments of the present application are connected properly. After confirming that there is no error, open the filter element test fixture device 4.

[0059] Step 2: Open the compressed air source 1. The saturated water vapor generating device 2 uses the compressed air provided by the compressed air source 1 to generate saturated water vapor and supply it to the dry and wet air mixing buffer device 3. The dry and wet air mixing buffer device 3 uses the compressed air provided by the compressed air source 1 and the saturated water vapor generated by the saturated water vapor generating device 2 to adjust the proportion of dry and wet air, and generates mixed air with the required target humidity and flows into the filter element test fixture device 4.

[0060] In some embodiments, if the test device for the water vapor filtration efficiency of the filter element further includes a plurality of solenoid valves and a plurality of flow controllers, then after opening the compressed air source 1 in step two, the compressed air source 1 can also be used to purge the system pipeline. Specifically, after opening the compressed air source 1, the first solenoid valve A1, the fourth solenoid valve A4, and the sixth solenoid valve A6 are opened simultaneously, and the second solenoid valve A2, the third solenoid valve A3, and the fifth solenoid valve A5 are closed, so that the dry compressed air flows through the system pipeline at a flow rate of 100 L / min to purge the residual gas inside. After purging for 8 - 10 minutes, all solenoid valves are closed to prepare for the start of the test.

[0061] In some embodiments, if the test device for the water vapor filtration efficiency of the filter element further includes a plurality of solenoid valves and a plurality of flow controllers, then step two can be: keeping the compressed air source 1 in the open state, opening the first solenoid valve A1, the second solenoid valve A2, the third solenoid valve A3, and the fifth solenoid valve A5, closing the fourth solenoid valve A4 and the sixth solenoid valve A6, respectively regulating the proportion of dry air and saturated water vapor entering the dry-wet air mixing buffer device 3 through the first flow controller B1 and the second flow controller B2, monitoring the humidity in the buffer tank main body 12 according to the temperature and humidity data of the first temperature and humidity sensor 10 in the dry-wet air mixing buffer device 3, and making the mixed gas flow out from the fifth solenoid valve A5 before reaching the target humidity. After reaching the target humidity, the fifth solenoid valve A5 is closed, and the fourth solenoid valve A4 and the sixth solenoid valve A6 are opened, so that the mixed gas with the required target humidity and flow rate flows into the filter element test fixture device 4.

[0062] Step three: The built-in sensor provided in the filter element test fixture device 4 measures the water vapor concentration at the front and rear ends of the respirator filter element to calculate the water vapor filtration efficiency.

[0063] Specifically, the built-in sensor of the filter element test fixture device 4 can calculate the water vapor filtration efficiency of the filter element by measuring the water vapor concentration at the front and rear ends of the respirator filter element and pressing the following (Formula 1): Water vapor filtration efficiency of the filter element = (Water vapor concentration at the front end of the respirator filter element - Water vapor concentration at the rear end of the respirator filter element) / Water vapor concentration at the front end of the respirator filter element (Formula 1).

[0064] In some embodiments, if the test device for the water vapor filtration efficiency of the filter element further includes a plurality of solenoid valves and a plurality of flow controllers, then after step three, it can further include: after the test is completed, closing the second solenoid valve A2 and the fifth solenoid valve A5, and opening the other solenoid valves, so that the compressed air flows through the system pipeline at a flow rate of 100 L / min to purge the residual gas inside the system pipeline. After purging for 8 - 10 minutes, the compressed air source 1 and all solenoid valves and flow controllers are closed.

[0065] It should be noted that the combination modes of the technical features in the embodiments of the present application are not limited to the combination modes recorded in the embodiments of the present application or the combination modes recorded in the specific embodiments. All the technical features recorded in the present application can be freely combined or combined in any way, unless contradictions occur between them.

[0066] As shown in the present application and the claims, unless the context clearly indicates an exceptional situation, words such as "a", "an" and / or "the" are not specifically singular and may also include the plural. Generally speaking, the term "comprising" only indicates the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.

[0067] The terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features.

[0068] The above are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. A test device for the water vapor filtration efficiency of a filter element, characterized in that It includes a compressed air source, a saturated steam generating device, a dry-wet air mixing and buffering device, a filter element test fixture device with built-in sensors, and a system pipeline. Among them, the compressed air source is respectively connected to the air inlet of the saturated steam generating device and the dry air inlet interface of the dry-wet air mixing and buffering device, and is used to provide compressed air for the saturated steam generating device and the dry-wet air mixing and buffering device; the saturated steam generating device is used to generate saturated steam by using the compressed air provided by the compressed air source; the outlet of the saturated steam generating device is connected to the saturated steam inlet interface of the dry-wet air mixing and buffering device; the dry-wet air mixing and buffering device is used to regulate the proportion of dry and wet air by using the compressed air provided by the compressed air source and the saturated steam generated by the saturated steam generating device, and generate mixed air with the required target humidity; the filter element test fixture device is connected to the mixed air exhaust port of the dry-wet air mixing and buffering device, and is used for the installation test of the respirator filter element to calculate the water vapor filtration efficiency by using the water vapor concentrations at the front and rear ends of the respirator filter element measured by the built-in sensors.

2. The water vapor filtration efficiency testing device for a filter element according to claim 1, characterized in that It also includes a plurality of solenoid valves and a plurality of flow controllers. The solenoid valves are used for controlling the air flow in the system pipeline, and the flow controllers are used for controlling the air flow in the system pipeline. The plurality of solenoid valves include a first solenoid valve, a second solenoid valve, a third solenoid valve, a fourth solenoid valve, a fifth solenoid valve, and a sixth solenoid valve. The plurality of flow controllers include a first flow controller and a second flow controller. The first solenoid valve and the first flow controller are connected in the circuit between the compressed air source and the dry-wet air mixing and buffering device, and the compressed air provided by the compressed air source enters the inside of the dry-wet air mixing and buffering device after passing through the first solenoid valve and the first flow controller. The second solenoid valve and the second flow controller are connected in the circuit between the compressed air source and the saturated steam generating device, and the compressed air provided by the compressed air source enters the inside of the saturated steam generating device after passing through the second solenoid valve and the second flow controller. The third solenoid valve is connected in the circuit between the saturated steam generating device and the dry-wet air mixing and buffering device, and the saturated steam produced by the saturated steam generating device enters the dry-wet air mixing and buffering device after passing through the third solenoid valve. The fourth solenoid valve is connected in the circuit between the dry-wet air mixing and buffering device and the filter element test fixture device; the fifth solenoid valve is directly connected to the circuit of the dry-wet air mixing and buffering device and is arranged in parallel with the fourth solenoid valve; the sixth solenoid valve is directly connected to the outlet of the filter element test fixture device.

3. The water vapor filtration efficiency test device for a filter element according to claim 1, wherein, The saturated steam generating device includes a water tank main body, a liquid level sensor, a temperature sensor, a heating rod, and an aeration element. Among them, the liquid level sensor and the temperature sensor are installed inside the water tank main body. The liquid level sensor is used for controlling the water level inside the water tank main body, and the temperature sensor is used for measuring the water temperature inside the water tank main body and for feedback regulation of the heating rod power; both the heating rod and the aeration element extend from the top to the bottom of the water tank main body; the aeration element is used to generate saturated steam after the compressed gas is in full contact with the heated water.

4. The water vapor filtration efficiency testing device for a filter element according to claim 3, characterized in that, The aeration element is made of sponge material.

5. The water vapor filtration efficiency testing device for a filter element according to claim 1, characterized in that, The dry-wet air mixing buffer device includes a first temperature and humidity sensor, a mixed air exhaust port, a buffer tank main body, and a drainage interface. The first temperature and humidity sensor extends from the top of the buffer tank main body to the inside of the buffer tank main body; the mixed air exhaust port is located at the top of the buffer tank main body and is used to discharge the mixed gas; the drainage interface is located at the bottom of the buffer tank main body and is used to discharge the condensed water formed by saturated water vapor inside the buffer tank main body.

6. The water vapor filtration efficiency testing device for a filter element according to claim 1, characterized in that The filter element test fixture device includes an upper half fixture, a lower half fixture, and a filter element interface base. The middle mating surfaces of the upper half fixture and the lower half fixture are sealed and connected through a sealing ring and a clamp; a filter element interface base for installing the filter element is also provided on the lower half fixture; The built-in sensors include a dew point sensor and a second temperature and humidity sensor. Among them, the second temperature and humidity sensor is installed above the upper half fixture and is used to measure the temperature and humidity of the air upstream of the filter element; the dew point sensor is installed below the lower half fixture and is used to measure the humidity of the air downstream of the filter element.

7. The water vapor filtration efficiency testing device for a filter element according to claim 6, wherein, The filter element interface base is set as a replaceable filter element interface base.

8. The water vapor filtration efficiency testing device for a filter element according to claim 6, characterized in that, The temperature measurement range of the second temperature and humidity sensor is -50°C to 180°C, and the accuracy is ±0.1°C; the humidity measurement range of the second temperature and humidity sensor is 0 to 100%RH, and the accuracy is 0.8%.

9. A test device for the water vapor filtration efficiency of a filter element, according to any one of claims 1 to 8, characterized in that The measurement range of the dew point sensor is -70~60℃T d , and the accuracy is ±0.1℃T d .

10. A method for testing the water vapor filtration efficiency of a filter element, characterized in that, Including: Step 1: Install the respirator filter element in the filter element test fixture device of a filter element water vapor filtration efficiency test device according to any one of claims 1 to 9; Step 2: Open the compressed air source. The saturated water vapor generating device uses the compressed air provided by the compressed air source to generate saturated water vapor and supply it to the dry-wet air mixing buffer device. The dry-wet air mixing buffer device uses the compressed air provided by the compressed air source and the saturated water vapor generated by the saturated water vapor generating device to adjust the proportion of dry and wet air, and generates mixed air with the required target humidity and flows into the filter element test fixture device; Step 3: The built-in sensors of the filter element test fixture device measure the water vapor content to calculate the water vapor filtration efficiency.

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