Test system and test method for measuring deposition of entrained liquid drops and aerosol

Abstract

The invention discloses a test system and a test method for measuring entrained liquid drop and aerosol deposition. The test system comprises a carrier gas generation pipeline, an aerosol distribution pipeline, a mixing pipeline, an entrained liquid drop generation and aerosol washing device, an entrained liquid drop size measurement device and an entrained liquid drop and aerosol filtering device, the carrier gas generation pipeline and the aerosol distribution pipeline are both connected with the mixing pipeline, the carrier gas generation pipeline provides carrier gas with different pressures and flows, the aerosol distribution pipeline provides water-insoluble aerosol with different concentrations, and the carrier gas and the aerosol are uniformly mixed in the mixing pipeline; the mixed pipeline is introduced into the entrained liquid drop generation and aerosol washing device, so that the carrier gas carrying the aerosol is washed and filtered to form entrained liquid drops in which the aerosol is deposited, and the entrained liquid drops enter the entrained liquid drop size measurement device for measuring the size distribution of the entrained liquid drops; and the liquid drops enter the entrained liquid drop and aerosol filtering device for aerosol and entrained liquid drop filtering retention.

Description

Technical Field

[0001] The present invention relates to the technical field of entrained droplets and aerosol testing in the nuclear field, and in particular to a test system and a test method for measuring entrained droplets and aerosol deposition. Background Art

[0002] After a serious accident at a nuclear power plant, a large amount of radioactive aerosols from the reactor's primary circuit are released into the containment. Under the action of specialized safety facilities, such as the operation of the spray system or the discharge of the suppression pool, the aerosols can be retained in the pit of a pressurized water reactor and the suppression pool of a boiling water reactor. When the accident causes the pool to boil, the rising bubbles will break up on the pool water surface, producing droplets. These droplets, entrained with the aerosols by the airflow, re-enter the gas phase, forming a radioactive source term. Furthermore, the same problem exists in wet containment filtration and discharge systems designed for serious accidents, such as venturi water scrubbing and submerged jet filtration. Radioactive aerosols retained in the scrubbing liquid are re-entrained by the gas and liquid, generating entrained droplets. The radioactive substances contained in these entrained droplets make them a new source term. The fission product release rate caused by the re-entrainment phenomenon is relatively small, but the duration is long, which will cause re-entrainment to contribute significantly to the source term in the secondary release effect. Therefore, the measurement of entrained droplets and aerosol deposition under different water washing conditions can provide data support for engineering applications such as comprehensive nuclear safety assessment and optimal design of containment filtration and exhaust systems.

[0003] There are relatively few experimental measurement schemes for the deposition of entrained droplets and aerosols. Research on entrained droplets is mainly focused on theoretical calculations. Patent No. CN202210250896.3 proposes a method for calculating entrained droplets in a downhole throttle of a gas well. This method is limited to the calculation of droplet entrainment under annular flow, but is not applicable to the calculation of droplets entrained at the liquid surface. Patent No. CN202211279166.2 proposes a method for predicting the entrainment behavior of droplets in the re-flooding of rectangular narrow slits in plate-like components. This method uses an artificial neural network prediction method to train the input-output relationship through a large amount of data, and can calculate the liquid entrainment rate value applicable to the re-flooding conditions of the bottom of most plate-like components. This method is compared with the calculations calculated by Relap5 software and has a certain degree of credibility, but there is no experimental data to support it.

[0004] Patent No. 201310497698.8 mentions a pressure vessel and method for simulating the entrainment of droplets in the upper chamber of a nuclear reactor. The entrained droplets are collected through a pipe into a water tank through a steam-water separator to achieve the measurement of the entrained droplets. Although this method can truly simulate the phenomenon of droplet entrainment in the upper chamber of the reactor, the overall design is relatively complex. It is impossible to characterize the entrained droplets containing radioactive aerosols. The use of a steam-water separator to collect entrained droplets may leave a lot of residue in the collection pipe. It is impossible to accurately measure the case of small entrainment amounts, and the device cannot experimentally measure the size distribution of entrained droplets.

[0005] In view of the above technical problems, the present invention is specially introduced. Summary of the Invention

[0006] The main purpose of the present invention is to provide a test system and test method for measuring entrained droplets and aerosol deposition, which can be used to realize the experimental measurement of the mass and size distribution of entrained droplets, the aerosol water washing filtration efficiency, and the aerosol deposition amount under different experimental conditions for different water washing forms.

[0007] To achieve the above objectives, according to one aspect of the present invention, a test system for measuring entrained droplet and aerosol deposition is proposed, comprising a carrier gas generation pipeline, an aerosol distribution pipeline, a mixing pipeline, an entrained droplet generation and aerosol water washing device, an entrained droplet size measurement device, and an entrained droplet and aerosol filtration device;

[0008] The carrier gas generating pipeline and the aerosol dispensing pipeline are both connected to the mixing pipeline, the carrier gas generating pipeline provides carrier gas of different pressures and flows, the aerosol dispensing pipeline provides water-insoluble aerosols of different concentrations, and the carrier gas and the aerosol are evenly mixed in the mixing pipeline;

[0009] The mixing pipeline leads to the entrained droplet generation and aerosol water washing device, so that the carrier gas carrying the aerosol is washed and filtered in the entrained droplet generation and aerosol water washing device to form entrained droplets of internally deposited aerosol. The entrained droplets enter the entrained droplet size measurement device for entrained droplet size distribution measurement, and enter the entrained droplet and aerosol filtration device for aerosol and entrained droplet filtration and retention.

[0010] Furthermore, the entrained droplet generation and aerosol water washing device includes a water washing chamber, a water washing nozzle and an upper hydrophobic pipeline. The water washing nozzle is located in the water washing chamber, the mixing pipeline passes into the water washing chamber and is connected to the water washing nozzle, and the upper hydrophobic pipeline is connected to the water washing chamber to control its liquid phase environment.

[0011] Furthermore, the test system also includes an aerosol water washing efficiency measuring device, which includes a first sampling tube and a second sampling tube. The first sampling tube is connected to the mixing pipe, and the second sampling tube passes through the side wall of the water washing chamber and extends into the water washing outlet position in the water washing chamber.

[0012] Furthermore, the entrained droplet generation and aerosol water washing device includes a laboratory bench support located at the bottom of the water washing chamber, and the laboratory bench support is provided with a main carrier gas inlet and an upper water drain inlet. The main carrier gas inlet is coordinated with the mixing pipeline, and the upper drain pipeline is coordinated with the upper water drain inlet.

[0013] Furthermore, the water washing nozzle is connected to the experimental bench support through a nozzle flange, and the water washing nozzle allows the carrier gas carrying the aerosol to form a bubbling or jet water washing form.

[0014] Furthermore, the side wall of the water washing chamber is a transparent cylinder, and the water washing nozzle and the inlet of the second sampling tube are both located at the center of the horizontal position in the water washing chamber.

[0015] Furthermore, the bottom of the side wall of the water washing chamber is fixedly connected to the flange of the experimental bench support through the cavity bottom flange, and a first sealing gasket is provided between the flange connections.

[0016] Furthermore, the entrained droplet size measuring device includes an entrained droplet measurement space and a laser particle size measuring device. The entrained droplet measurement space is connected to the water washing chamber, and transparent measurement windows are symmetrically provided on the side walls of the entrained droplet measurement space. The laser particle size measuring device includes a laser emitting end and a laser receiving end. The laser emitting end emits a measuring laser which passes through the transparent measurement windows on both sides in turn to reach the laser receiving end.

[0017] Furthermore, the entrained droplet and aerosol filtering device includes a multi-stage fiber filtering device and a zeolite absorption device, the multi-stage fiber filtering device is arranged between the entrained droplet size measuring device and the zeolite absorption device, and the entrained droplet size measuring device, the multi-stage fiber filtering device and the zeolite absorption device are connected in sequence.

[0018] Furthermore, the multi-stage fiber filtration device includes a fiber filtration channel and multi-stage filtration fibers. The multi-stage filtration fibers are arranged at intervals in the fiber filtration channel and fixed on the side walls of the fiber filtration channel. The porosity of the multi-stage filtration fibers decreases successively in the direction in which the entrained droplets pass, so as to filter and retain the entrained droplets and aerosols at the micron level.

[0019] Furthermore, the multi-stage fiber filtration device also includes a first fixing clamp, and the multi-stage filter fibers are fixed to the side wall of the fiber filtration channel through the first fixing clamp, and a second sealing gasket is provided between the upper and lower sides of each stage of filter fibers and the first fixing clamp.

[0020] Furthermore, the zeolite absorption device includes a zeolite absorption channel, a first zeolite and a third fixing clamp. The zeolite absorption channel is connected to the fiber filtration channel. The first zeolite is fixed in the zeolite absorption channel by the third fixing clamp. The first zeolite absorbs the entrained droplets at the nanometer level.

[0021] Furthermore, the bottom of the multi-stage fiber filtration device is connected to the top flange of the measuring space at the top of the entrained droplet size measuring device through the bottom flange of the filtration channel, and the top of the multi-stage fiber filtration device is connected to the bottom flange of the absorption channel at the bottom of the zeolite absorption device through the top flange of the filtration channel.

[0022] Furthermore, a post filter is provided at the outlet of the zeolite absorption device, and the post filter is connected to the atmosphere.

[0023] Furthermore, the carrier gas generation pipeline and the aerosol distribution pipeline both include a gas generation processing module, and the aerosol distribution pipeline further includes a pressure reducing valve, a first flow meter, and an aerosol generator connected downstream of the gas generation processing module.

[0024] Furthermore, the carrier gas generation pipeline also includes a second flow meter, a first pressure gauge and a control valve connected downstream of the gas generation processing module.

[0025] Furthermore, the gas generation and processing module includes an air compressor, a pre-filter, a gas storage container and a second zeolite which are connected in sequence.

[0026] Furthermore, the outlet of the aerosol generator is connected to the mixing pipeline through an L-shaped distribution pipeline, and a second pressure gauge is also provided on the mixing pipeline.

[0027] To achieve the above object, according to another aspect of the present invention, a test method for measuring entrained droplets and aerosol deposition is provided, using the test system described above and comprising the following steps:

[0028] Test preparation steps: replace the water washing nozzle according to the working conditions and water washing form required by the test, control the upper hydrophobic pipeline to ensure the required liquid phase environment in the water washing chamber, adjust the carrier gas generation pipeline to provide the required pressure and flow of carrier gas, and adjust the aerosol distribution pipeline to provide the required concentration and flow of aerosol;

[0029] The test is carried out as follows: the carrier gas and the aerosol are uniformly mixed in a mixing pipeline and then introduced into an entrained droplet generation and aerosol water washing device, so that the carrier gas carrying the aerosol is water-washed and filtered in the entrained droplet generation and aerosol water washing device to form entrained droplets of internally deposited aerosol;

[0030] a parameter measurement step in which an aerosol water washing efficiency measuring device samples and measures the aerosol through two sampling tubes respectively to obtain the aerosol concentration before and after water washing and filtration to obtain the aerosol water washing and filtration efficiency; and an entrained droplet size measuring device measures the size distribution of the entrained droplets;

[0031] The weighing and calculation step comprises the following steps: the entrained droplets are filtered and retained by the entrained droplets and the aerosol filter device; after the test is completed, the entrained droplets and the filtrate in the aerosol filter device are taken out and weighed, and the aerosol water-washed deposition amount is obtained by calculation.

[0032] Furthermore, in the weighing calculation step, the multi-stage filter fiber is taken out and weighed as a whole to obtain the weight gain M1. After the weighing is completed, washing, filtering, drying, and weighing operations are performed to obtain the deposition amount M2 of the aerosol in the entrained droplets. The first zeolite is taken out and weighed as a whole to obtain the weight gain M3. The total mass of the entrained droplets is M1-M2+M3.

[0033] The application of the technical solution of the present invention achieves at least the following beneficial effects:

[0034] 1. The test system of the present invention can meet the simulation experiments of entrained droplets and aerosol water washing deposition measurement under different experimental conditions and different water washing forms. It can measure one or more targets among multiple important parameters such as aerosol water washing filtration efficiency, entrained droplet size distribution, entrained droplets and aerosol deposition amount.

[0035] 2. The test system of the present invention solves the problem of difficulty in measuring the size distribution and entrained amount of entrained droplets on the liquid surface during the water washing process by designing an entrained droplet size measurement device and an entrained droplet and aerosol filtration device, and the measurement results are relatively accurate.

[0036] 3. The test system of the present invention adopts a multi-modular design, and flange connections are mostly used between devices and accessories, making assembly and disassembly very convenient. Multiple sealing gaskets are designed to ensure airtightness and improve test accuracy.

[0037] 4. The devices in the test system of the present invention mostly adopt visual design, which facilitates timely acquisition of test conditions. Combined with the test method proposed by the present invention, data acquisition and data processing are simple and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The accompanying drawings, which constitute part of the present invention, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0039] Figure 1 A schematic diagram of a test system according to an embodiment is shown;

[0040] Figure 2 A cross-sectional view of an aerosol water washing device according to one embodiment is shown;

[0041] Figure 3 A cross-sectional view of an entrained droplet size measurement device according to one embodiment is shown;

[0042] Figure 4 A cross-sectional view of a multi-stage fiber filtration device according to one embodiment is shown;

[0043] Figure 5 A cross-sectional view of a zeolite absorption device according to one embodiment is shown.

[0044] The above drawings include the following reference numerals:

[0045] 1. Air compressor; 2. Pre-filter; 3. Air storage container; 4. Second zeolite; 5. Second flowmeter; 6. First pressure gauge; 7. Control valve; 8. Second pressure gauge; 9. Pressure reducing valve; 10. First flowmeter; 11. Aerosol generator; 12. Drain line; 13. Water supply pump; 14. Water washing nozzle; 15. Water washing chamber; 16. Aerosol washing efficiency measurement device; 17. Entrained droplet measurement space; 18. Laser particle size measurement device; 19. Multi-stage fiber filtration device; 20. Zeolite absorption device; 21. Post-filter

[0046] 15.1. Laboratory bench support; 15.2. First sealing gasket; 15.3. Chamber bottom flange; 15.4. Main carrier gas inlet; 15.5. Nozzle flange; 15.6. Water drain inlet; 15.7. Water wash chamber sidewall; 15.8. Second sampling tube; 15.9. Chamber top flange;

[0047] 17.1, bottom flange of measurement space; 17.2, cavity wall of measurement space; 17.3, transparent measurement window; 17.4, top flange of measurement space; 18.1, laser emitting end; 18.2, laser receiving end;

[0048] 19.1, filter channel bottom flange; 19.2, first fixing clamp; 19.3, primary filter fiber; 19.4, secondary filter fiber; 19.5, tertiary filter fiber; 19.6, second sealing gasket; 19.7, filter channel top flange;

[0049] 20.1, bottom flange of absorption channel; 20.2, first zeolite; 20.3, third fixing clamp; 20.4, top flange of absorption channel; 20.5, outlet flange;

[0050] 100. Carrier gas generation pipeline; 200. Aerosol distribution pipeline; 300. Mixing pipeline; 400. Entrained droplet generation and aerosol water washing device; 500. Entrained droplet size measurement device; 600. Entrained droplet and aerosol filtration device. DETAILED DESCRIPTION

[0051] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0052] The present invention is described in further detail below with reference to specific embodiments. These embodiments are not to be construed as limiting the scope of protection claimed by the present invention. The term "including" when used indicates the presence of a feature, but does not exclude the presence or addition of one or more other features; the terms "lateral", "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for ease of description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be construed as limiting the present invention; in addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be construed as indicating or implying relative importance.

[0053] In this description, it should be noted that, unless otherwise specified or limited, the terms "installed," "connected," and "connected" should be understood broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of these terms in the present invention. Furthermore, in the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0054] Example:

[0055] The present invention proposes a test system for measuring entrained droplets and aerosol deposition, such as Figure 1 As shown, it includes a carrier gas generating pipeline 100, an aerosol dispensing pipeline 200, a mixing pipeline 300, an entrained droplet generating and aerosol washing device 400, an entrained droplet size measuring device 500, and an entrained droplet and aerosol filtering device 600.

[0056] The ends of the carrier gas generation line 100 and the aerosol distribution line 200 are both connected to the mixing line 300. The carrier gas generation line 100 provides carrier gas of varying pressures and flow rates, while the aerosol distribution line 200 provides water-insoluble aerosols of varying concentrations. The carrier gas and aerosol are uniformly mixed in the mixing line 300. Preferably, the aerosol in this embodiment uses water-insoluble titanium dioxide aerosol.

[0057] The mixing line 300 is led into the entrained droplet generation and aerosol washing device 400, so that the carrier gas carrying the aerosol is washed and filtered in the entrained droplet generation and aerosol washing device 400 to form entrained droplets of internally deposited aerosol. The entrained droplets enter the entrained droplet size measurement device 500 for entrained droplet size distribution measurement, and enter the entrained droplet and aerosol filtering device 600 for aerosol and entrained droplet filtration and retention.

[0058] In this way, the test system of the present invention can meet the simulation experiments of entrained droplets and aerosol water washing deposition measurement under different experimental conditions and different water washing forms, and can measure one or more targets among multiple important parameters such as aerosol water washing filtration efficiency, entrained droplet size distribution, entrained droplets and aerosol deposition amount.

[0059] Specifically, both the carrier gas generation pipeline 100 and the aerosol distribution pipeline 200 include a gas generation and processing module, which includes an air compressor 1, a pre-filter 2, a gas storage container 3, and a second zeolite 4, which are connected in sequence. The air generated by the air compressor 1 is processed by the pre-filter 2 and the second zeolite 4 to produce clean carrier gas.

[0060] Furthermore, the aerosol distribution pipeline 200 also includes a pressure reducing valve 9, a first flowmeter 10, and an aerosol generator 11 connected downstream of the gas generation and processing module. The carrier gas generation pipeline 100 also includes a second flowmeter 5, a first pressure gauge 6, and a control valve 7 connected downstream of the gas generation and processing module. The second flowmeter 5 and the first pressure gauge 6 in the carrier gas generation pipeline 100 are used to monitor the flow rate and pressure of the carrier gas, respectively. The pressure reducing valve 9 in the aerosol distribution pipeline 200 adjusts the concentration of the distributed aerosol by controlling the gas pressure, and the first flowmeter 10 is used to monitor the flow rate of the aerosol distribution pipeline 200.

[0061] Preferably, the outlet of the aerosol generator 11 is connected to the mixing line 300 via an L-shaped distribution line, which is also equipped with a second pressure gauge 8. The high-pressure gas in the aerosol distribution line 200 flows through the L-shaped distribution line on the air duct of the aerosol generator 11, blowing the aerosol into a fluidized and boiling state and delivering it into the carrier gas, ensuring that the two are evenly mixed in the mixing line 300.

[0062] Combine Figure 1and Figure 2 As shown, the entrained droplet generation and aerosol washing device 400 includes a washing chamber 15, a washing nozzle 14, and an upper drain line. The washing nozzle 14 is located within the washing chamber 15. The mixing line 300 flows into the washing chamber 15 and connects to the washing nozzle 14. The washing nozzle 14 causes the aerosol-carrying carrier gas to form a bubbling or jet-like washing pattern. The upper drain line connects to the washing chamber 15 to control its liquid phase environment. The upper drain line includes a drain line 12 with a control valve and a water supply line with a water supply pump 13.

[0063] The test system also includes an aerosol water-washing efficiency measurement device 16, which includes a first sampling tube and a second sampling tube 15.8. The first sampling tube connects to the mixing line 300, while the second sampling tube 15.8 extends through the sidewall 15.7 of the water-washing chamber and into the water-washing outlet of the water-washing chamber 15. The aerosol water-washing filtration efficiency can be calculated by sampling the upstream and downstream aerosol concentrations using the aerosol water-washing efficiency measurement device 16.

[0064] Preferably, the mixing line 300 is a stainless steel pipe with an inner diameter of 50 mm. An L-shaped aerosol sampling tube with an inner diameter of 6 mm is welded to the pipe wall as the first sampling tube for measuring the aerosol concentration at the inlet. A second aerosol sampling tube with an inner diameter of 6 mm is inserted into the gas phase above the liquid phase in the water wash chamber 15 as the second sampling tube 15.8 to measure the aerosol concentration at the outlet. Aerosol sampling and measurement are performed using a particle size spectrometer to meet the requirements for measuring the number concentration of different aerosol sizes. The sample gas flow rate through the instrument probe should be stable at 5 L / min.

[0065] Furthermore, the entrained droplet generation and aerosol water washing device 400 includes a laboratory bench support 15.1 located at the bottom of the water washing chamber 15, and the laboratory bench support 15.1 is provided with a main carrier gas inlet 15.4 and an upper water drain inlet 15.6. The main carrier gas inlet 15.4 cooperates with the mixing pipeline 300, and the upper drain pipeline cooperates with the upper water drain inlet 15.6.

[0066] like Figure 2 As shown, the water washing nozzle 14 is connected to the experimental bench support 15.1 through the nozzle flange 15.5 to facilitate the replacement of water washing nozzles 14 of different sizes and models.

[0067] Preferably, the water-wash chamber sidewall 15.7 is a transparent cylinder, and the water-wash nozzle 14 and the inlet of the second sampling tube 15.8 are both located horizontally at the center of the water-wash chamber 15. The bottom of the water-wash chamber sidewall 15.7 is fixedly connected to the flange of the laboratory bench support 15.1 via a chamber bottom flange 15.3, and a first sealing gasket 15.2 is provided between the flange connections to ensure sealing.

[0068] Combine Figure 3 As shown, entrained droplets from the internally deposited aerosol flow upward into an entrained droplet size measurement device 500, where their size is measured using high-speed photography. The entrained droplet size measurement device 500 includes an entrained droplet measurement space 17 and a laser particle size measurement device 18. The entrained droplet measurement space 17 is connected to the water wash chamber 15. Transparent measurement windows 17.3 are symmetrically positioned on the sidewalls of the entrained droplet measurement space 17. The laser particle size measurement device 18 includes a laser emitting port 18.1 and a laser receiving port 18.2. Laser emitting port 18.1 emits a measuring laser beam, which sequentially passes through the transparent measurement windows 17.3 on either side and reaches the laser receiving port 18.2.

[0069] Preferably, the side wall of the entrained droplet measurement space 17 comprises a cylindrical measurement space cavity wall 17.2, and the transparent measurement window 17.3 is connected to both sides of the measurement space cavity wall 17.2 via flanges.

[0070] Combine Figure 4 and Figure 5 As shown, after size measurement, the entrained droplets of the internally deposited aerosol continue upward and enter the entrained droplet and aerosol filtering device 600. The entrained droplet and aerosol filtering device 600 includes a multi-stage fiber filtering device 19 and a zeolite absorption device 20, which are arranged in sequence. The multi-stage fiber filtering device 19 is arranged between the entrained droplet size measuring device 500 and the zeolite absorption device 20, and the entrained droplet size measuring device 500, the multi-stage fiber filtering device 19, and the zeolite absorption device 20 are sequentially connected.

[0071] Specifically, the multi-stage fiber filtration device 19 includes a fiber filtration channel and multi-stage filtration fibers. The multi-stage filtration fibers are arranged at intervals in the fiber filtration channel and fixed on the side walls of the fiber filtration channel. The porosity of the multi-stage filtration fibers decreases successively in the direction of passage of entrained droplets, so as to filter and retain entrained droplets and aerosols at the micron level.

[0072] Preferably, in this embodiment, Figure 4 As shown, the multi-stage filter fiber includes primary filter fiber 19.3, secondary filter fiber 19.4, and tertiary filter fiber 19.5. Entrained droplets from internally deposited aerosols pass sequentially through the high-porosity primary filter fiber 19.3, the medium-porosity secondary filter fiber 19.4, and the low-porosity tertiary filter fiber 19.5, completing the filtration and retention of micron-scale entrained droplets and aerosol deposits.

[0073] The multi-stage fiber filtration device 19 also includes a first fixing clamp 19.2, through which the multi-stage filter fibers are fixed to the side wall of the fiber filtration channel, and a second sealing gasket 19.6 is provided between the upper and lower sides of each stage of filter fibers and the first fixing clamp 19.2 to ensure sealing.

[0074] like Figure 5 As shown, the zeolite absorption device 20 includes a zeolite absorption channel, a first zeolite 20.2, and a third fixing clamp 20.3. The zeolite absorption channel is connected to the fiber filtration channel. The first zeolite 20.2 is fixed in the zeolite absorption channel by the third fixing clamp 20.3. The first zeolite 20.2 absorbs nano-scale entrained droplets. Third sealing gaskets are installed between the upper and lower sides of the first zeolite 20.2 and the third fixing clamp 20.3 to ensure sealing.

[0075] Furthermore, a post-filter 21 is provided at the outlet of the zeolite absorption device 20 , and the post-filter 21 is connected to the atmosphere so as to discharge all the gas after absorbing the entrained droplets and aerosols out of the test system.

[0076] Combine Figure 2-Figure 5 As shown, preferably, the bottom of the entrained droplet size measurement device 500 is connected to the chamber top flange 15.9 at the top of the water washing chamber 15 via the measurement space bottom flange 17.1. The bottom of the multi-stage fiber filtration device 19 is connected to the measurement space top flange 17.4 at the top of the entrained droplet size measurement device 500 via the filtration channel bottom flange 19.1.

[0077] The top of the multi-stage fiber filter 19 is connected to the absorption channel bottom flange 20.1 at the bottom of the zeolite absorber 20 via the filter channel top flange 19.7. The absorption channel top flange 20.4 at the top of the zeolite absorber 20 is connected to the outlet flange 20.5.

[0078] Sealing gaskets can be set between the above flange connections to ensure airtightness. The test system of the present invention adopts a multi-modular design, and flange connections are mostly used between devices and accessories, making assembly and disassembly very convenient. The use of multiple sealing gaskets ensures airtightness and improves test accuracy.

[0079] The present invention also provides a test method for measuring entrained droplets and aerosol deposition, using the test system described above, and comprising the following steps:

[0080] Experimental preparation step S1, replace the water washing nozzle 14 according to the working conditions and water washing form required for the test, control the upper hydrophobic pipeline so that the water washing chamber 15 has the required liquid phase environment, adjust the carrier gas generation pipeline 100 to provide the required pressure and flow of carrier gas, and adjust the aerosol distribution pipeline 200 to provide the required concentration and flow of aerosol.

[0081] The test proceeds to step S2, where the carrier gas and aerosol are evenly mixed in the mixing pipe 300 and then passed into the entrained droplet generation and aerosol water washing device 400, so that the carrier gas carrying the aerosol is washed and filtered in the entrained droplet generation and aerosol water washing device 400 to form entrained droplets of internally deposited aerosol.

[0082] In parameter measurement step S3, the aerosol water washing efficiency measuring device 16 samples and measures the aerosol through two sampling tubes respectively, obtains the aerosol concentration before and after water washing and filtration, and obtains the aerosol water washing and filtration efficiency. The entrained droplet size measuring device 500 measures the size distribution of the entrained droplets.

[0083] In the weighing calculation step S4, the entrained droplets are filtered and retained by the entrained droplets and the aerosol filter device 600. After the test is completed, the entrained droplets and the filtered material in the aerosol filter device 600 are taken out and weighed, and the aerosol water-washed deposition amount is obtained by calculation.

[0084] In the weighing calculation step S4, the multi-stage filter fiber is taken out and weighed as a whole to obtain the weight gain M1. After the weighing is completed, washing, filtering, drying, and weighing operations are performed to obtain the deposition amount M2 of the aerosol in the entrained droplets. The first zeolite 20.2 is taken out and weighed as a whole to obtain the weight gain M3. The total mass of the entrained droplets is M1-M2+M3.

[0085] The devices in the test system of the present invention mostly adopt visual design, which is convenient for timely acquisition of test conditions. Combined with the test method proposed by the present invention, data acquisition and data processing are simple and reliable.

[0086] In summary, from the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0087] 1. The test system of the present invention can meet the simulation experiments of entrained droplets and aerosol water washing deposition measurement under different experimental conditions and different water washing forms. It can measure one or more targets among multiple important parameters such as aerosol water washing filtration efficiency, entrained droplet size distribution, entrained droplets and aerosol deposition amount.

[0088] 2. The test system of the present invention solves the problem of difficulty in measuring the size distribution and entrained amount of entrained droplets on the liquid surface during the water washing process by designing an entrained droplet size measurement device and an entrained droplet and aerosol filtration device, and the measurement results are relatively accurate.

[0089] 3. The test system of the present invention adopts a multi-modular design, and flange connections are mostly used between devices and accessories, making assembly and disassembly very convenient. Multiple sealing gaskets are designed to ensure airtightness and improve test accuracy.

[0090] 4. The devices in the test system of the present invention mostly adopt visual design, which is convenient for timely acquisition of test conditions. Combined with the test method proposed by the present invention, data acquisition and data processing are simple and reliable.

[0091] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A test system for measuring entrained droplets and aerosol deposition, characterized in that: The device comprises a carrier gas generating pipeline (100), an aerosol dispensing pipeline (200), a mixing pipeline (300), an entrained droplet generating and aerosol washing device (400), an entrained droplet size measuring device (500), and an entrained droplet and aerosol filtering device (600); The carrier gas generating pipeline (100) and the aerosol dispensing pipeline (200) are both connected to the mixing pipeline (300), the carrier gas generating pipeline (100) provides carrier gas of different pressures and flow rates, and the aerosol dispensing pipeline (200) provides water-insoluble aerosols of different concentrations, and the carrier gas and the aerosol are uniformly mixed in the mixing pipeline (300); the mixing pipeline (300) is passed into the entrained droplet generating and aerosol washing device (400), so that the carrier gas carrying the aerosol is washed and filtered in the entrained droplet generating and aerosol washing device (400) to form entrained droplets of internally deposited aerosol, and the entrained droplets enter the entrained droplet size measuring device (500) for entrained droplet size distribution measurement, and enter the entrained droplet and aerosol filtering device (600) for aerosol and entrained droplet filtration and retention.

2. The test system according to claim 1, characterized in that: The entrained droplet generation and aerosol water washing device (400) comprises a water washing chamber (15), a water washing nozzle (14) and an upper hydrophobic pipeline, wherein the water washing nozzle (14) is located in the water washing chamber (15), the mixing pipeline (300) leads into the water washing chamber (15) and is connected to the water washing nozzle (14), and the upper hydrophobic pipeline is connected to the water washing chamber (15) to control its liquid phase environment.

3. The test system according to claim 2, characterized in that: The test system further comprises an aerosol water washing efficiency measuring device (16), the aerosol water washing efficiency measuring device (16) comprising a first sampling tube and a second sampling tube (15.8), the first sampling tube being connected to the mixing pipeline (300), and the second sampling tube (15.8) passing through the side wall (15.7) of the water washing chamber and extending into the water washing outlet position in the water washing chamber (15).

4. The test system according to claim 3, characterized in that: The entrained droplet generation and aerosol water washing device (400) comprises a laboratory bench support (15.1) located at the bottom of the water washing chamber (15); a main carrier gas inlet (15.4) and an upper water drain inlet (15.6) are provided on the laboratory bench support (15.1); the main carrier gas inlet (15.4) cooperates with the mixing pipeline (300), and the upper drain pipeline cooperates with the upper water drain inlet (15.6).

5. The test system according to claim 4, characterized in that: The water washing nozzle (14) is connected to the experimental bench support (15.1) via a nozzle flange (15.5), and the water washing nozzle (14) causes the carrier gas carrying the aerosol to form a bubbling or jetting water washing form.

6. The test system according to claim 5, characterized in that: The side wall (15.7) of the water washing chamber is a transparent cylinder, and the inlet of the water washing nozzle (14) and the second sampling tube (15.8) are both located at the center of the horizontal position in the water washing chamber (15).

7. The test system according to claim 4, characterized in that: The bottom of the water washing chamber side wall (15.7) is fixedly connected to the flange of the experimental bench support (15.1) through the chamber bottom flange (15.3), and a first sealing gasket (15.2) is provided between the flange connections.

8. The test system according to claim 2, characterized in that: The entrained droplet size measuring device (500) comprises an entrained droplet measurement space (17) and a laser particle size measuring device (18). The entrained droplet measurement space (17) is connected to the water washing chamber (15). Transparent measurement windows (17.3) are symmetrically arranged on the side walls of the entrained droplet measurement space (17). The laser particle size measuring device (18) comprises a laser emitting end (18.1) and a laser receiving end (18.2). The laser emitting end (18.1) emits a measuring laser which sequentially passes through the transparent measurement windows (17.3) on both sides and reaches the laser receiving end (18.2).

9. The test system according to claim 1, characterized in that: The entrained droplet and aerosol filtering device (600) comprises a multi-stage fiber filtering device (19) and a zeolite absorption device (20), wherein the multi-stage fiber filtering device (19) is arranged between the entrained droplet size measuring device (500) and the zeolite absorption device (20), and the entrained droplet size measuring device (500), the multi-stage fiber filtering device (19) and the zeolite absorption device (20) are sequentially connected.

10. The test system according to claim 9, characterized in that: The multi-stage fiber filtration device (19) comprises a fiber filtration channel and multi-stage filtration fibers, wherein the multi-stage filtration fibers are arranged at intervals in the fiber filtration channel and fixed on the side walls of the fiber filtration channel, and the porosity of the multi-stage filtration fibers decreases in the direction in which the entrained droplets pass, so as to filter and retain the entrained droplets and the aerosol at the micron level.

11. The test system according to claim 10, characterized in that: The multi-stage fiber filtration device (19) further comprises a first fixing clamp (19.2), the multi-stage filter fibers are fixed to the side wall of the fiber filtration channel via the first fixing clamp (19.2), and a second sealing gasket (19.6) is provided between the upper and lower sides of each stage of filter fibers and the first fixing clamp (19.2).

12. The test system according to claim 10, characterized in that: The zeolite absorption device (20) comprises a zeolite absorption channel, a first zeolite (20.2) and a third fixing clamp (20.3); the zeolite absorption channel is connected to the fiber filtration channel; the first zeolite (20.2) is fixed in the zeolite absorption channel via the third fixing clamp (20.3); and the first zeolite (20.2) absorbs the entrained droplets at the nanometer level.

13. The test system according to any one of claims 9 to 12, characterized in that: The bottom of the multistage fiber filter device (19) is connected to the measuring space top flange (17.4) at the top of the entrained droplet size measuring device (500) via the filter channel bottom flange (19.1), and the top of the multistage fiber filter device (19) is connected to the absorption channel bottom flange (20.1) at the bottom of the zeolite absorption device (20) via the filter channel top flange (19.7).

14. The test system according to claim 12, characterized in that: A post filter (21) is provided at the outlet of the zeolite absorption device (20), and the post filter (21) is connected to the atmosphere.

15. The test system according to claim 1, wherein: The carrier gas generation pipeline (100) and the aerosol distribution pipeline (200) both include a gas generation processing module, and the aerosol distribution pipeline (200) further includes a pressure reducing valve (9), a first flow meter (10), and an aerosol generator (11) connected downstream of the gas generation processing module.

16. The test system according to claim 15, characterized in that: The carrier gas generation pipeline (100) further comprises a second flow meter (5), a first pressure gauge (6) and a control valve (7) connected downstream of the gas generation processing module.

17. The test system according to claim 15 or 16, characterized in that: The gas generation and processing module comprises an air compressor (1), a pre-filter (2), a gas storage container (3), and a second zeolite (4) which are connected in sequence.

18. The test system according to claim 15, characterized in that: The outlet of the aerosol generator (11) is connected to the mixing pipeline (300) via an L-shaped distribution pipeline, and a second pressure gauge (8) is also provided on the mixing pipeline (300).

19. A test method for measuring entrained droplets and aerosol deposition, characterized in that: Use the test system according to any one of claims 1 to 18, comprising the following steps: Test preparation step S1, replacing the water washing nozzle (14) according to the working conditions and water washing form required for the test, controlling the upper hydrophobic pipeline so that the water washing chamber (15) has the required liquid phase environment, adjusting the carrier gas generation pipeline (100) to provide the required pressure and flow of carrier gas, and adjusting the aerosol distribution pipeline (200) to provide the required concentration and flow of aerosol; The test proceeds to step S2, wherein the carrier gas and the aerosol are mixed uniformly in the mixing pipe (300) and then introduced into the entrained droplet generation and aerosol water washing device (400), so that the carrier gas carrying the aerosol is washed and filtered in the entrained droplet generation and aerosol water washing device (400) to form entrained droplets of the internally deposited aerosol; In a parameter measurement step S3, the aerosol water washing efficiency measuring device (16) samples and measures the aerosol through two sampling tubes respectively, obtains the aerosol concentration before and after water washing and filtration, and obtains the aerosol water washing and filtration efficiency, and the entrained droplet size measuring device (500) measures the size distribution of the entrained droplets; In the weighing calculation step S4, the entrained droplets are filtered and retained by the entrained droplets and the aerosol filter device (600). After the test is completed, the entrained droplets and the filtered material in the aerosol filter device (600) are taken out and weighed, and the aerosol water-washed deposition amount is obtained by calculation.

20. The test method according to claim 19, characterized in that: In the weighing calculation step S4, the multi-stage filter fiber is taken out and weighed as a whole to obtain the weight gain M1. After weighing, washing, filtering, drying, and weighing operations are performed to obtain the deposition amount M2 of the aerosol in the entrained droplets. The first zeolite (20.2) is taken out and weighed as a whole to obtain the weight gain M3. The total mass of the entrained droplets is M1-M2+M3.

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