Outdoor Dual Smoke Chamber System and Method for Simulating the Generation of New Particles in the Atmosphere

Abstract

This invention discloses an outdoor dual-smoke chamber system, comprising two identical smoke chambers: a reference chamber and a variable chamber. Each smoke chamber includes an inner chamber containing a reaction chamber, the outer layer of which is covered with an inert material film. A sample gas collection and diffusion channel is located on the inner chamber and communicates with the reaction chamber. The dual-smoke chamber system further includes a characteristic substance injection system, a variable injection system, and a detection system. The output of the characteristic substance injection system is connected to the sample gas collection and diffusion channels on both the reference and variable chambers. The variable injection system is connected to the sample gas collection and diffusion channel on the variable chamber. The detection system is connected to the reaction chamber on both the reference and variable chambers. A method for simulating the generation of new atmospheric particles is also disclosed. This invention can simultaneously capture ambient air using dual smoke chambers, and identify and quantify sensitive parameters affecting the generation process of new atmospheric particles through real-time comparison and control.

Description

Technical Field

[0001] This invention relates to the fields of atmospheric science and chemical engineering, specifically to an outdoor dual smoke chamber system and a method for simulating the generation of new particles in the ambient atmosphere. Background Technology

[0002] Air pollution is a major challenge hindering environmental governance and people's livelihoods in my country, with fine particulate matter (PM2.5) pollution being a core component. Monitoring data shows that although the mass concentration of particulate matter has decreased significantly in recent years, the number concentration has remained almost unchanged, posing a potential threat to human health and the ecological environment. One reason for the persistently high number concentration of particulate matter is the strong potential for the generation and growth of new particles in my country's atmosphere. However, the mechanisms underlying the generation of new atmospheric particles are still unclear, and existing parameters for new particle generation from abroad cannot directly explain the phenomenon of new atmospheric particle generation in my country.

[0003] The generation of new particles is divided into two stages: nucleation and growth. Several key parameters of this two-stage process, such as generation rate, growth rate, and susceptible species, need to be characterized through smoke chamber simulation experiments. However, most experimental parameters are currently obtained through indoor smoke chambers, which are typically conducted under artificial light sources such as ultraviolet lamps. The parameters obtained from these indoor experiments differ significantly from those under natural conditions. Existing outdoor smoke chamber technologies generally employ a static single-layer design, which cannot achieve rapid generation and growth of new particles. Furthermore, the two-stage process is influenced by multiple factors, such as the type and concentration of gaseous precursors, atmospheric oxidizing properties, and condensation pools; however, the mechanisms by which these factors affect new particle generation have not yet been quantitatively elucidated.

[0004] Given that the formation of new particles is a significant cause of air pollution in my country, and that existing technologies lack key characterization techniques for the formation of new particles, this invention primarily addresses the aforementioned technical problems. Summary of the Invention

[0005] To address the existing technical problems, this invention provides an outdoor dual smoke chamber system and a method for simulating the generation of new particles in the ambient atmosphere. This system overcomes the bottleneck in existing technologies that cannot rapidly oxidize the ambient atmosphere to generate new particles, and also solves the problem of difficulty in quantifying the influencing factors of new particle generation.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0007] An outdoor dual smoke box system includes two smoke boxes with identical structures, the two smoke boxes being a reference box and a variable box, respectively.

[0008] The smoke chamber includes an inner chamber, the outer layer of which is covered with a transparent film. A reaction chamber is provided inside the inner chamber, the outer layer of which is covered with an inert film. A sample gas collection and diffusion channel is provided on the inner chamber, which is connected to the reaction chamber. A temperature sensor and a humidity sensor are provided inside the reaction chamber.

[0009] The dual smoke chamber system also includes a characteristic substance injection system, a variable injection system, and a detection system. The output of the characteristic substance injection system is connected to the sample gas collection and diffusion channels on the reference chamber and the variable chamber, respectively. The variable injection system is connected to the sample gas collection and diffusion channel on the variable chamber, and the detection system is connected to the reaction chamber on the reference chamber and the variable chamber, respectively.

[0010] Preferably, the smoke box further includes a light shield mechanism, which includes a rectangular frame located outside the inner box body, the rectangular frame being covered with a light shield film, a slide rail and a round shaft on the rectangular frame, the round shaft being connected to the output end of the motor, one end of the light shield film being wound around the round shaft, and both sides of the light shield film being slidably connected to the slide rail by sliders.

[0011] The slide rail is provided with intermittently distributed locking blocks, which are rotatably connected to the slide rail.

[0012] In this design, the light-shielding film covers five sides of a rectangular box: top, front, back, left, and right. The two sides of the film are slidably connected to slide rails, and the end of the film is connected to a cylindrical shaft. Specifically, a motor drives the shaft to rotate, causing the film to move back and forth along the slide rails, thus expanding or contracting the film. The slide rails are spaced out with locking blocks. When a block is opened, the front end of the film will lock at the block as it moves forward, stopping at the block. Returning the block to its original position allows the film to continue moving forward, achieving a preset exposure level and automatically controlling the gradient intensity of sunlight radiation.

[0013] Preferably, a solar spectrometer and a reflector are provided on the inner bottom of the inner box, and the solar spectrometer and the reflector are located below the reaction chamber.

[0014] In this scheme, the solar spectrometer can measure the solar radiation forcing entering the reaction chamber; the reflector is installed below the bottom of the gas reaction chamber to reflect sunlight, enhance the radiation intensity of the reaction chamber, and make the radiation intensity of the reaction chamber close to that of the outdoor environment.

[0015] Preferably, the feature substance injection system includes an air compressor, a zero-gas unit, and a monodisperse particulate matter generator connected in sequence. The output end of the monodisperse particulate matter generator is connected to the sample gas collection and diffusion channels on the reference box and the variable box respectively through a first conversion box.

[0016] In this scheme, a characteristic substance injection system is connected to two reaction chambers via an injection switching box to ensure the consistency of the input substances in the two reaction chambers and reduce comparison errors. The zero gas unit is used to provide dry and clean gas, which is introduced into the reaction chambers before and after the experiment. The zero gas unit can generate high concentrations of ozone to oxidize and clean the low volatile organic compounds adhering to the walls of the reaction chambers. The monodisperse particle generator provides particles of the characteristic particle size to create a specific condensation pool in the reaction chambers.

[0017] Preferably, the injection conversion box includes an injection box body, which is provided with an injection input pipe and two injection output pipes. Both injection output pipes are connected to the injection input pipe, and a switching valve is provided on each of the two injection output pipes. The output end of the monodisperse particulate matter generator is connected to the injection input pipe, and the two injection output pipes are respectively connected to the sample gas collection and diffusion channels on the reference box and the variable box.

[0018] Preferably, the variable injection system includes an injection pump and a gas mixing chamber. Both the injection pump and the zero gas unit are connected to the input end of the gas mixing chamber, and the output end of the gas mixing chamber is connected to the sample gas collection and diffusion channel on the variable tank.

[0019] In this scheme, the injection pump is used to inject liquid or gaseous volatile organic compounds. The volatile organic compounds are mixed evenly with the dry and clean gas generated by the zero gas unit in the gas mixing chamber. The volatile organic compounds are the nucleation precursors of new particles to be screened (such as various amine organic compounds). After the variable gas is injected, the trend of new particles in the variable chamber is observed to determine whether the new particle generation is sensitive to the variable gas.

[0020] Preferably, the detection system includes a particulate matter detection device and a gaseous substance detection device. The input end of the particulate matter detection device is connected to the reaction chambers on the reference box and the variable box respectively through a particulate matter detection switching box; the gaseous substance detection device is connected to the reaction chambers on the reference box and the variable box respectively through a gas detection switching box.

[0021] This scheme utilizes a shared detection system for both reaction chambers to ensure consistency in detection between the two chambers, reduce detection errors, and save on detection costs. The particulate matter detection device is a scanning electromobility particle size spectrometer (SEM), used to analyze the particle size distribution and number concentration of new particles, calculate the nucleation and growth rates of new particles, determine the trend of new particles, compare the differences between the two smoke chambers, and further analyze the influence of variable factors. The gaseous substance detection device is an online atmospheric pressure soft ionization chemical mass spectrometer (APMS), used to analyze low-volatile organic compounds and intermediate chemical products within the reaction chamber, and screen for sensitive precursors for new particle nucleation and growth.

[0022] Preferably, the particulate matter detection switching box and the gas detection switching box have the same structure, specifically including a detection box body. The detection box body is provided with a detection output tube, a first input tube, a second input tube, and a third input tube. The first input tube, the second input tube, and the third input tube are all connected to the detection output tube. An electric T-type ball valve is provided at the connection between the first input tube, the second input tube, and the third input tube and the detection output tube. The detection output tube is connected to the particulate matter detection device and the gaseous substance detection device. The first input tube is connected to the reaction chamber on the reference box. The second input tube is connected to the reaction chamber on the variable box. The third input tube is connected to the ambient atmosphere.

[0023] Preferably, the inner chamber is equipped with an antistatic needle, a ventilation fan, and an air pump, with the air pump connected to the reaction chamber via a pipe.

[0024] In this scheme, the antistatic needle removes static electricity from the surface of the inert material film, thereby reducing the adsorption effect of new particle walls. Turning on the ventilation fan ensures uniform temperature distribution in the reaction chamber, and the vacuum pump is used to maintain a constant volume in the reaction chamber.

[0025] A method for simulating the generation of new particles in the ambient atmosphere, employing the aforementioned outdoor dual smoke chamber system, specifically includes the following steps:

[0026] S1. Cleaning the reaction chamber: High-concentration ozone is generated by the ozone generator in the zero gas unit and injected into the reaction chamber through the injection conversion box. The smoke box is exposed to sunlight, and high-concentration free radicals are generated inside the reaction chamber to clean the impurity gases inside the reaction chamber and oxidize and remove the low-volatile organic compounds adhering to the walls of the reaction chamber.

[0027] S2. Consistency verification of reference box and variable box: Before injecting variable gas, open the light shield mechanism and measure the nucleation rate and growth rate of new particles in the reference box and variable box. If the relative error of the parameters obtained by the reference box and variable box is <10%, the consistency verification is passed.

[0028] S3. Setting experimental parameters:

[0029] S31. Set the flow rate at the sampling port of the sample gas collection and diffusion channel;

[0030] S32. Set up a condensation pool in the reaction chamber;

[0031] S33. Set the temperature and humidity inside the reaction chamber;

[0032] S4. Set variable species and concentration: Determine the research variables that affect the generation and growth of new particles to be tested;

[0033] S5. Start exposure and generate new particles: Open the light shield mechanism to expose the smoke box, drive the chemical reaction inside the reaction chamber to form new particles, start the motor, and quickly expose. After exposure, new particles are quickly generated inside the reaction chamber and continue to grow in size.

[0034] S6. Measuring particulate matter concentration: Using a particulate matter detection device, continuously measure the particle size distribution and number concentration of new particles, record the number of newly formed stable nanoparticles per unit time, i.e. calculate the nucleation rate J of new particles, and record the rate at which the particle size increases over time, i.e. calculate the growth rate GR of new particles.

[0035] S7. Measuring gaseous substance concentration: Using a gaseous substance detection device to measure the species, concentration and time changes of reaction products in the reaction chamber, and to screen sensitive precursors for new particle nucleation and growth;

[0036] S8. Comparison of measured data and model data: The species and concentrations of gaseous precursors, low volatile organic compounds, and gaseous organic oxidation products are included in the box model to simulate and calculate the nucleation rate J and the new particle growth rate GR. The results are compared and verified with the actual measured J and GR. If the verification is consistent, it indicates that the traditional understanding of the generation and growth of new particles of the precursor is supported.

[0037] S9. Proposal of new particles, new mechanisms, and new parameters: If the nucleation rate J and the growth rate GR of new particles calculated by the box model simulation are inconsistent with the actual measured J and GR, introduce parameter sensitivity S, determine the species of sensitive gaseous precursors based on parameter sensitivity S, and at the same time correct the model parameters / mechanisms, re-simulate and calculate until they are consistent with the actual measured J and GR, verify the new parameters and new mechanisms, and after verification, propose new particles, new mechanisms, and new parameters.

[0038] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0039] (1) The present invention provides an outdoor smoke box reactor. The reactor has a unique multi-membrane nesting feature, which enables the captured ambient air to undergo rapid chemical reaction to generate new particles, and the new particle parameters are more realistic and representative.

[0040] (2) The present invention provides a dual smoke chamber, which is divided into a reference chamber and a variable chamber. It can simultaneously capture the ambient atmosphere with the dual smoke chamber and identify and quantify the sensitive parameters affecting the generation process of new particles in the atmosphere through real-time comparison and control.

[0041] (3) The design of the smoke chamber of this invention breaks through the traditional static design. It uses the air of the ambient atmosphere captured by the flow type as the sample gas, which drives the continuous particle size growth of new particles and solves the problem of difficult control of the generation of new atmospheric particles.

[0042] (4) The dual smoke box device described in this invention is portable and flexible. In addition to carrying out scientific research on atmospheric pollution prevention and control, it can also be placed in an atmospheric environment observation station to test the generation and growth potential of new atmospheric particles in my country for a long time. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the overall structure of the dual smoke box system of the present invention;

[0044] Figure 2 for Figure 1 A schematic diagram of the injection conversion box in the diagram;

[0045] Figure 3 for Figure 1 A schematic diagram of the particulate matter detection switching box in the diagram;

[0046] Figure 4 for Figure 1 A schematic diagram of the gas detection switching box in the middle;

[0047] Figure 5 This is a flowchart of the method for simulating the generation of new particles in the ambient atmosphere according to the present invention;

[0048] Figure 6 This is a PLC control circuit diagram of the particulate matter detection switching box and the gas detection switching box in this invention;

[0049] Figure 7 This is a control circuit diagram of the two electric T-type ball valves inside the particulate matter detection switching box and the gas detection switching box in this invention. Detailed Implementation

[0050] The present invention will be further described in detail below with reference to experimental examples and specific embodiments. However, this should not be construed as limiting the scope of the above-mentioned subject matter of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0051] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0052] As attached Figure 1 -Appendix Figure 4The illustrated outdoor dual smoke chamber system includes two identical smoke chambers, serving as a reference chamber and a variable chamber, respectively. The two smoke chambers share the same structure and materials for their components, ensuring consistency in measurement results under conditions without variable injection. The reference chamber and variable chamber are used to modify sensitive factors in atmospheric particle formation, such as adding different concentrations of seed particles to generate different concentrations of condensation sinks, adding different types of variable gases to identify species directly involved in nucleation and with significant impact, or setting different light radiation intensities.

[0053] The smoke chamber includes an inner chamber 1-3, which includes a cubic frame covered with a transparent membrane 1-4. A reaction chamber 1-1 is located inside the inner chamber 1-3, covered with an inert membrane. The reaction chamber 1-1 has a cylindrical structure. A sample gas collection and diffusion channel 1-2 is located on the inner chamber 1-3, containing a semi-permeable membrane. A flow meter and a sampling pump are installed at the sampling port of the sample gas collection and diffusion channel 1-2. The sample gas collection and diffusion channel 1-2 is connected to the reaction chamber 1-1. Sample gas enters the sample gas collection and diffusion channel 1-2, passes through the semi-permeable membrane to filter particulate matter, and then diffuses through the semi-permeable membrane into the reaction chamber 1-1. A temperature sensor and a humidity sensor are installed inside the reaction chamber 1-1.

[0054] The outer layer of the reaction chamber 1-1 is an inert thin film that allows ultraviolet light from sunlight to pass through. The ultraviolet sunlight triggers a chemical reaction in the gas, generating gaseous free radicals. These gaseous free radicals oxidize and enter the ambient atmosphere inside the reaction chamber 1-1, producing low-volatile organic compounds. These low-volatile gaseous products then undergo a chemical reaction to generate molecular clusters of 1-3 nanometers. These molecular clusters continuously absorb the low-volatile gaseous products from the reaction products and further grow into new particles of 3-600 nanometers.

[0055] The transparent material film 1-4 allows sunlight to pass through the ultraviolet band, and the antistatic needle 1-5 removes static electricity from the surface of the inert material film, thereby reducing the adsorption effect of new particle walls.

[0056] An antistatic needle 1-5 and a ventilation fan 1-6 are installed at the top of the inner chamber 1-3. An air pump 1-7, a solar spectrometer 3-1, and a reflector 3-2 are installed at the bottom inner side of the inner chamber 1-3. The air pump 1-7 is connected to the reaction chamber 1-1 via a pipe. The solar spectrometer 3-1 and the reflector 3-2 are located below the reaction chamber 1-1. The solar spectrometer 3-1 measures the solar radiation forcing entering the reaction chamber 1-1. The reflector 3-2 is installed at the bottom of the reaction chamber 1-1 to reflect sunlight, enhancing the radiation intensity of the reaction chamber 1-1 and making its radiation intensity close to that of the outdoor environment.

[0057] In this embodiment, the smoke box also includes a light shield mechanism 2, which includes a rectangular frame 2-1 located outside the inner box 1-3. The rectangular frame 2-1 is covered with a light shield film 2-2, which covers the top of the rectangular frame 2-1 and its four circumferential sides. The inner box 1-3 is located within the area enclosed by the light shield film 2-2. The rectangular frame 2-1 is also provided with slide rails 2-4 and circular shafts 2-5. Specifically, slide rails 2-4 are provided on both sides of the upper end face and on both sides of the lower end face of the rectangular frame 2-1. The slide rails 2-4 extend along the length of the rectangular frame 2-1. The circular shafts 2-5 are located at the ends of the slide rails 2-4. The circular shafts 2-5 are connected to the output end of the motor 2-3. One end of the light-shielding film 2-2 is wrapped around the circular shaft 2-5. The two sides of the light-shielding film 2-2 are slidably connected to the slide rails 2-4 by sliders. The motor 2-3 drives the circular shaft 2-5 to rotate, thereby moving the light-shielding film 2-2 back and forth along the slide rails 2-4 to realize the exposure and light-shielding process of the smoke box.

[0058] Locking blocks are spaced apart on the slide rail 2-4, and these blocks are rotatably connected to the slide rail 2-4. When a certain exposure is needed, the corresponding locking block is rotated, and the slider connected to the end of the light-shielding film 2-2 will stop at the locking block. When other exposures are needed, the locking block at that position is retracted, and then the locking blocks at the corresponding positions for other exposures are rotated out, thus automatically achieving gradient control of sunlight radiation intensity. The automated gradient control of sunlight radiation function enables precise control of the time and speed of new particle generation, significantly improving the simulation efficiency of new particle generation.

[0059] The dual smoke chamber system further includes a characteristic substance injection system 5, a variable injection system 6, and a detection system 7. The output end of the characteristic substance injection system 5 is connected to the sample gas collection and diffusion channels 1-2 on the reference chamber and the variable chamber, respectively. The variable injection system 6 is connected to the sample gas collection and diffusion channels 1-2 on the variable chamber, and the detection system 7 is connected to the reaction chamber 1-1 on the reference chamber and the variable chamber, respectively.

[0060] The characteristic substance injection system 5 includes an air compressor 5-1, a zero gas unit 5-2, and a monodisperse particulate matter generator 5-3 connected in sequence. The output end of the monodisperse particulate matter generator 5-3 is connected to the sample gas collection and diffusion channels 1-2 on the reference box and the variable box respectively through a first conversion box 4-1. The zero gas unit 5-2 is used to provide clean gas. Clean gas is introduced into the reaction chamber 1-1 before and after the experiment. The zero gas unit 5-2 can generate high concentrations of ozone to oxidize and clean the low-volatile organic compounds adhering to the walls of the reaction chamber 1-1. The monodisperse particulate matter generator 5-3 provides particulate matter of a characteristic size to create a specific condensation pool in the reaction chamber 1-1.

[0061] refer to Figure 2 The injection conversion box 4-1 includes an injection box body, which contains an injection input pipe 4-1-1 and two injection output pipes 4-1-2. Both injection output pipes 4-1-2 are connected to the injection input pipe 4-1-1, and each of the two injection output pipes 4-1-2 is equipped with a switching valve 4-1-3. The output end of the monodisperse particulate matter generator 5-3 is connected to the injection input pipe 4-1-1, and the two injection output pipes 4-1-2 are respectively connected to the sample gas collection and diffusion channels 1-2 on the reference box and the variable box. The switching of the switching valves can be controlled by a PLC. PLC control is existing technology and will not be described in detail. In actual operation, the switching sequence and switching interval can be flexibly adjusted by modifying the PLC system program according to different experimental requirements.

[0062] The variable injection system 6 includes an injection pump 6-1 and a gas mixing chamber 6-2. The injection pump 6-1 and the zero gas unit 5-2 are connected to the input end of the gas mixing chamber 6-2, and the output end of the gas mixing chamber 6-2 is connected to the sample gas collection and diffusion channel 1-2 on the variable chamber. The injection pump 6-1 is used to inject liquid or gaseous volatile organic compounds. The volatile organic compounds are mixed evenly with the dry and clean gas generated by the zero gas unit 5-2 in the gas mixing chamber 6-2. The volatile organic compounds are the nucleation precursors of new particles to be screened (such as various amine organic compounds). After the variable gas is injected, the trend of new particles in the variable chamber is observed to determine whether the new particle generation is sensitive to the variable gas.

[0063] The detection system includes a particulate matter detection device 7-1 and a gaseous substance detection device 7-2. The input end of the particulate matter detection device 7-1 is connected to the reaction chamber 1-1 on the reference box and the variable box respectively through a particulate matter detection switching box 4-3. The gaseous substance detection device 7-2 is connected to the reaction chamber 1-1 on the reference box and the variable box respectively through a gas detection switching box 4-2. The particulate matter detection device 7-1 is a scanning electromobility particle size spectrometer, used to analyze the particle size distribution and number concentration of new particles, calculate the nucleation rate and growth rate of new particles, determine the trend of new particles, compare the differences between the two smoke boxes, and then analyze the influence of variable factors. The gaseous substance detection device 7-2 is an online atmospheric pressure soft ionization chemical mass spectrometer, used to analyze low volatile organic compounds and intermediate chemical products in the reaction chamber 1-1, and screen sensitive precursors for the nucleation and growth of new particles.

[0064] refer to Figure 3 and Figure 4 The particulate matter detection switching box 4-3 and the gas detection switching box 4-2 have the same structure, specifically including detection boxes 4-3-1 and 4-2-1. The detection boxes 4-3-1 and 4-2-1 are equipped with detection output tubes 4-3-2 and 4-2-2, first input tubes 4-3-3 and 4-2-3, second input tubes 4-3-4 and 4-2-4, and third input tubes 4-3-5 and 4-2-5. The first input tubes 4-3-3 and 4-2-3, the second input tubes 4-3-4 and 4-2-4, and the third input tubes 4-3-5 and 4-2-5 are all connected to the detection output tubes 4-3-2 and 4-2-2. The first input tubes 4-3-3 and 4-2-3, the second input tubes 4-3-4 and 4-2-4, and the third input tubes 4-3-5 and 4-2-5 are all connected to the detection output tubes 4-3-2 and 4-2-2. Electric T-type ball valves 4-3-6 and 4-2-6 are installed at the connection points between the third input pipes 4-2-4 and the detection output pipes 4-3-2 and 4-2-2. The design of the electric T-type ball valves 4-3-6 and 4-2-6 helps to reduce the pressure change in the pipeline during switching. The detection output pipes 4-3-2 and 4-2-2 are connected to the particulate matter detection device 7-1 and the gaseous substance detection device 7-2. The first input pipes 4-3-3 and 4-2-3 are connected to the reaction chamber 1-1 on the reference box. The second input pipes 4-3-4 and 4-2-4 are connected to the reaction chamber 1-1 on the variable box. The third input pipes 4-3-5 and 4-2-5 are connected to the ambient atmosphere. The difference between the gas detection switching box 4-2 and the particulate matter detection switching box 4-3 is that the gas detection switching box 4-2 has a larger diameter Teflon tubing inside (the inert material itself does not volatilize organic matter and does not interfere with detection), while the particulate matter detection switching box 4-3 has a stainless steel tubing inside (to prevent static electricity from causing particulate matter loss).

[0065] refer to Figure 6 and Figure 7 The circuit control principle and process of the particulate matter detection switching box 4-3 and the gas detection switching box 4-2 are as follows: The switching of the first, second, and third input tubes is controlled by the combined rotation of two electric T-type ball valves inside the box. The rotation of the electric T-type ball valves is controlled by a programmable logic controller (PLC) program, and the PLC includes external relays and indicator lights. The PLC's input terminals include X00, X01, and X02, all connected to 24V voltage. Correspondingly, Y00, Y01, and Y02 are the PLC's output terminals. Y00, Y01, and Y02 each contain three sub-ports: COM, normally open, and normally closed. The COM port is connected to 24V power. The normally open ports of Y00 and Y01 are connected to relays 1K and 2K, respectively. The PLC program adjusts the on / off state of the normally open ports, thereby controlling the on / off state of relays 1K and 2K. The relays are connected to electric T-ball valves. The on / off state of the relays drives the rotation of the electric T-ball valves. The combined rotation of two electric T-ball valves controls the opening and closing of the first, second, and third input transistors, achieving the effect of switching between the three input transistors. When indicator light HR is on, the PLC master program is off; when indicator light HG is on, the PLC master program is on.

[0066] A method for simulating the generation of new particles in the ambient atmosphere, employing... Figure 1 -Appendix Figure 4 The outdoor dual smoke box system described herein specifically includes the following steps:

[0067] S1. Cleaning reaction chamber 1-1: High-concentration ozone is generated using the ozone generator in the zero gas unit 5-2 and injected into the reaction chamber 1-1 through the injection conversion box 4-1. The smoke box is exposed to sunlight, and high-concentration free radicals are generated inside the reaction chamber 1-1 to clean the impurity gases inside the reaction chamber 1-1 and oxidize and remove the low-volatile organic compounds adhering to the chamber wall of the reaction chamber 1-1.

[0068] S2. Consistency verification of reference box and variable box: Before injecting variable gas, open the light shield mechanism 2 and measure the nucleation rate and growth rate of new particles in the reference box and variable box. If the relative error of the parameters obtained by the reference box and variable box is <10%, the consistency verification is passed.

[0069] S3. Setting experimental parameters:

[0070] S31. Set the flow rate of the sampling port of sample gas collection and diffusion channel 1-2 to 50-70 L / min, and monitor the flow rate in real time to ensure that there is no fluctuation.

[0071] S32. Set up the condensation pool of reaction chamber 1-1: Determine the particle size of the monodisperse particles, adjust the concentration of monodisperse particles generated by injection system 5, and the monodisperse particles play a role in suppressing the super-burst growth of new particles in reaction chamber 1-1 to meet the requirements of the gaseous oxide condensation pool in smoke reaction chamber 1-1. Mix the determined sample gas with the seed aerosol and inject it into reaction chamber 1-1.

[0072] S33. Set the temperature and humidity inside the reaction chamber 1-1: Use a temperature sensor to detect the temperature inside the reaction chamber 1-1 and adjust the temperature to make the temperature of the reaction chamber 1-1 reach the target value. At the same time, turn on the ventilation fan 1-6 to ensure that the temperature distribution in the reaction chamber 1-1 is uniform. Use a humidity sensor to detect the relative humidity of the airflow inside the reaction chamber 1-1 and change the ratio of saturated humidity airflow to dry airflow to make the humidity inside the reaction chamber 1-1 reach the set value.

[0073] S4. Set variable species and concentration: Determine the research variables that affect the generation and growth of new particles to be tested. Variables usually refer to different organic and inorganic gases, light radiation intensity, condensation sink concentration, etc. Among them, organic and inorganic gases are generated by variable injection system 6, light radiation intensity is controlled by light shield mechanism 2, and condensation sink concentration is generated by characteristic substance injection system 5.

[0074] S5. Start exposure and generate new particles: Open the light shield mechanism 2 to expose the smoke box, drive the chemical reaction inside the reaction chamber 1-1 to form new particles, start the motor 2-3 for rapid exposure. After exposure, new particles are rapidly generated inside the reaction chamber 1-1 and continue to grow in size. By rotating the locking block on the slide rail 2-4, the light shield 2-2 is stopped at the locking block position to achieve the preset exposure degree. The solar radiation spectrometer 3-1 records the exposed solar radiation intensity. When the solar radiation intensity is a variable factor, set different exposure degrees for the variable box and the reference box.

[0075] S6. Measuring particulate matter concentration: Using particulate matter detection device 7-1, continuously measure the particle size distribution and number concentration of new particles, record the number of newly formed stable nanoparticles per unit time, i.e. calculate the nucleation rate J of new particles, and record the rate at which the particle size increases over time, i.e. calculate the growth rate GR of new particles.

[0076] S7. Measuring the concentration of gaseous substances: Using the gaseous substance detection device 7-2, measure the species, concentration and time changes of the reaction products, namely low volatile organic compounds and gaseous organic oxidation products (OOMs), in the reaction chamber 1-1 to screen for sensitive precursors of new particle nucleation and growth.

[0077] S8. Comparison of measured data and model data: The species and concentrations of gaseous precursors, low volatile organic compounds, and gaseous organic oxidation products are included in the box model to simulate and calculate the nucleation rate J and the new particle growth rate GR. The results are compared and verified with the actual measured J and GR. If the verification is consistent, it indicates that the traditional understanding of the generation and growth of new particles of the precursor is supported.

[0078] S9. Proposal of new particles, new mechanisms, and new parameters: If the nucleation rate J and the growth rate GR of new particles calculated by the box model simulation are inconsistent with the actual measured J and GR, introduce parameter sensitivity S, determine the species of sensitive gaseous precursors based on parameter sensitivity S, and at the same time correct the model parameters / mechanisms, re-simulate and calculate until they are consistent with the actual measured J and GR, verify the new parameters and new mechanisms, and after verification, propose new particles, new mechanisms, and new parameters.

[0079] The preferred embodiments of the present invention have been described above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. An outdoor dual smoke box system, characterized in that: It includes two identical smoke boxes, which are a reference box and a variable box, respectively. The smoke chamber includes an inner chamber (1-3), the outer layer of which is covered with a transparent film (1-4). The inner chamber (1-3) contains a reaction chamber (1-1), the outer layer of which is covered with an inert film. The inner chamber (1-3) is provided with a sample gas collection and diffusion channel (1-2), which is connected to the reaction chamber (1-1). The reaction chamber (1-1) contains a temperature sensor and a humidity sensor. The dual smoke chamber system further includes a characteristic substance injection system (5), a variable injection system (6), and a detection system (7). The output end of the characteristic substance injection system (5) is connected to the sample gas collection and diffusion channels (1-2) on the reference chamber and the variable chamber, respectively. The variable injection system (6) is connected to the sample gas collection and diffusion channels (1-2) on the variable chamber. The detection system (7) is connected to the reaction chamber (1-1) on the reference chamber and the variable chamber, respectively. The feature substance injection system (5) includes an air compressor (5-1), a zero gas unit (5-2), and a monodisperse particulate matter generator (5-3) connected in sequence. The output end of the monodisperse particulate matter generator (5-3) is connected to the sample gas collection and diffusion channel (1-2) on the reference box and the variable box respectively through the injection conversion box (4-1). The injection conversion box (4-1) includes an injection box body, which is provided with an injection input pipe (4-1-1) and two injection output pipes (4-1-2). The two injection output pipes (4-1-2) are both connected to the injection input pipe (4-1-1), and a switching valve (4-1-3) is provided on each of the two injection output pipes (4-1-2). The output end of the monodisperse particulate matter generator (5-3) is connected to the injection input pipe (4-1-1), and the two injection output pipes (4-1-2) are respectively connected to the sample gas collection and diffusion channels (1-2) on the reference box and the variable box. The detection system (7) includes a particulate matter detection device (7-1) and a gaseous substance detection device (7-2). The input end of the particulate matter detection device (7-1) is connected to the reaction chamber (1-1) on the reference box and the variable box respectively through a particulate matter detection switching box (4-3); the gaseous substance detection device (7-2) is connected to the reaction chamber (1-1) on the reference box and the variable box respectively through a gas detection switching box (4-2). The particulate matter detection switching box (4-3) and the gas detection switching box (4-2) have the same structure. Specifically, they include a detection box body, on which a detection output tube, a first input tube, a second input tube, and a third input tube are provided. The first input tube, the second input tube, and the third input tube are all connected to the detection output tube. An electric T-type ball valve is provided at the connection between the first input tube, the second input tube, and the third input tube and the detection output tube. The detection output tube is connected to the particulate matter detection device (7-1) and the gaseous substance detection device (7-2). The first input tube is connected to the reaction chamber (1-1) on the reference box. The second input tube is connected to the reaction chamber (1-1) on the variable box. The third input tube is connected to the ambient atmosphere.

2. The outdoor dual smoke box system according to claim 1, characterized in that: The smoke box also includes a light shield mechanism (2), which includes a rectangular frame (2-1) located outside the inner box (1-3). The rectangular frame (2-1) is covered with a light shield film (2-2). The rectangular frame (2-1) is also provided with a slide rail (2-4) and a round shaft (2-5). The round shaft (2-5) is connected to the output end of the motor (2-3). One end of the light shield film (2-2) is wrapped around the round shaft (2-5). The two sides of the light shield film (2-2) are slidably connected to the slide rail (2-4) by sliders. There are locking blocks spaced apart on the slide rail (2-4), and the locking blocks are rotatably connected to the slide rail (2-4).

3. The outdoor dual smoke box system according to claim 2, characterized in that: The inner bottom of the inner box (1-3) is provided with a solar spectrometer (3-1) and a reflector (3-2), which are located below the reaction chamber (1-1).

4. The outdoor dual smoke box system according to claim 3, characterized in that: The variable injection system (6) includes an injection pump (6-1) and a gas mixing chamber (6-2). The injection pump (6-1) and the zero gas unit (5-2) are both connected to the input end of the gas mixing chamber (6-2). The output end of the gas mixing chamber (6-2) is connected to the sample gas collection and diffusion channel (1-2) on the variable box.

5. The outdoor dual smoke box system according to claim 4, characterized in that: The inner box (1-3) is equipped with an antistatic needle (1-5), a ventilation fan (1-6), and an air pump (1-7). The air pump (1-7) is connected to the reaction chamber (1-1) through a pipe.

6. A method for simulating the generation of new particles in the ambient atmosphere, characterized in that, The outdoor dual smoke box system according to any one of claims 3-5 specifically includes the following steps: S1. Cleaning the reaction chamber (1-1): High-concentration ozone is generated by the ozone generator in the zero gas unit (5-2) and injected into the reaction chamber (1-1) through the injection conversion box (4-1). The smoke box is exposed to sunlight, and high-concentration free radicals are generated inside the reaction chamber (1-1). This cleans the impurity gases inside the reaction chamber (1-1) and oxidizes and removes the low-volatile organic compounds adhering to the walls of the reaction chamber (1-1). S2. Consistency verification of reference box and variable box: Before injecting variable gas, open the light shield mechanism (2) and measure the nucleation rate and growth rate of new particles in the reference box and variable box. If the relative error of the parameters obtained by the reference box and variable box is <10%, the consistency verification is passed. S3. Setting experimental parameters: S31. Set the flow rate of the sampling port in the sample gas collection and diffusion channel (1-2); S32. Set up a condensation pool for the reaction chamber (1-1); S33. Set the temperature and humidity inside the reaction chamber (1-1); S4. Set variable species and concentration: Determine the research variables that affect the generation and growth of new particles to be tested; S5. Start exposure and generate new particles: Open the light shield mechanism (2) to expose the smoke box, drive the chemical reaction inside the reaction chamber (1-1) to form new particles, start the motor (2-3) for rapid exposure, after exposure, new particles are rapidly generated inside the reaction chamber (1-1) and the particle size continues to grow. S6. Measure particulate matter concentration: Use particulate matter detection device (7-1) to continuously measure the particle size distribution and number concentration of new particles, record the number of newly formed stable nanoparticles per unit time, i.e. calculate the nucleation rate J of new particles, and record the rate at which the particle size increases over time, i.e. calculate the growth rate GR of new particles. S7. Measuring gaseous substance concentration: Using a gaseous substance detection device (7-2), measure the species, concentration and time changes of the reaction products in the reaction chamber (1-1) to screen for sensitive precursors for new particle nucleation and growth; S8. Comparison of measured data and model data: The species and concentrations of gaseous precursors, low volatile organic compounds, and gaseous organic oxidation products are included in the box model to simulate and calculate the nucleation rate J and the new particle growth rate GR. The results are compared and verified with the actual measured J and GR. If the verification is consistent, it indicates that the traditional understanding of the generation and growth of new particles of the precursor is supported. S9. Proposal of new particles, new mechanisms, and new parameters: If the nucleation rate J and the growth rate GR of new particles calculated by the box model simulation are inconsistent with the actual measured J and GR, introduce parameter sensitivity S, determine the species of sensitive gaseous precursors based on parameter sensitivity S, and at the same time correct the model parameters / mechanisms, re-simulate and calculate until they are consistent with the actual measured J and GR, verify the new parameters and new mechanisms, and after verification, propose new particles, new mechanisms, and new parameters.

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