A device and experimental method for real-time simulation of actual atmospheric chemical reactions

Abstract

The present invention provides a device for simulating atmospheric chemical reactions in real time, comprising a main reactor, which comprises, from the outside to the inside, an outer negative pressure refrigeration chamber, a middle transverse reaction chamber, and an inner sample gas permeation diffusion chamber, a polymethacrylic plate and a light reflecting plate being arranged on the outer negative pressure refrigeration chamber, a negative pressure pump, an electrostatic eliminator, a heat exchanger, and a turbulent fan being arranged in the outer negative pressure refrigeration chamber, a cylindrical membrane cabin made of polytetrafluoroethylene being arranged on the middle transverse reaction chamber, a drive assembly for driving the middle transverse reaction chamber to rotate being arranged on the axial direction of the middle transverse reaction chamber, a permeable membrane being arranged on the inner sample gas permeation diffusion chamber, the permeable membrane being in contact with the interior of the middle transverse reaction chamber, an airflow assembly being connected to the front and rear ends of the inner sample gas permeation diffusion chamber, a refrigeration system, a detection system, a seed aerosol injection system, and a control box being connected to the main reactor. The three-layer structural design of the present invention solves the problem that current technologies cannot simulate atmospheric chemical reactions continuously and in real time, significantly improves the gas exchange rate, reduces aerosol wall loss, and fully and realistically simulates the chemical reaction process of the ambient atmosphere.

Description

Technical Field

[0001] The present invention relates to the field of atmospheric science and technology, and in particular to a device and an experimental method for simulating atmospheric chemical reactions in real time. Background Art

[0002] In recent years, my country's air pollution situation has been alleviated, but it still faces huge challenges. The average annual ozone concentration in many cities is still far from meeting the standard. With the advancement of pollution control, the characteristics of air pollution have changed significantly. Recent studies have shown that the contribution rate of particulate matter generated by secondary transformation to winter haze has continued to increase, and ozone chemically transformed from nitrogen oxides and volatile organic compounds in summer has also become the primary pollutant in my country's urban areas. Therefore, it is particularly important to identify complex atmospheric chemical mechanisms. At present, although my country has established a complete observation system, such as fine particulate matter (PM 2.5 ), nitrogen dioxide (NO2), and ozone (O3), but detecting these species is insufficient to explore complex atmospheric chemical reactions. The atmosphere contains thousands of organic and inorganic gases that can undergo chemical reactions, particularly under conditions of high radiative forcing, generating large amounts of secondary aerosols, ozone, and other secondary pollutants, further exacerbating air pollution. Therefore, clarifying the mechanisms of atmospheric chemical reactions is of great guiding significance for scientific management of the atmosphere.

[0003] Currently, research on the mechanisms of chemical reactions in the real atmosphere is limited, primarily due to a lack of stable simulation devices and methods. Atmospheric chemistry simulation techniques, both domestically and internationally, primarily utilize smog chambers. These chambers utilize ultraviolet or xenon lamps to artificially generate strong ultraviolet light sources. The oxidizing properties within the reaction chamber are 1-3 orders of magnitude higher than those in the real atmosphere. This can lead to the fragmentation of some gas molecules and the generation of additional chemical reactions that are inconsistent with actual atmospheric conditions, resulting in significant uncertainty. The parameters obtained from the experiments lack true representation, which in turn leads to uncertainty in air quality model simulations. Furthermore, existing outdoor smog chamber techniques are limited in scope and lack the ability to collect and control flowing airflow, making continuous atmospheric chemistry simulation and observation impossible.

[0004] In summary, existing research has many shortcomings in the device technology for simulating real atmospheric chemical reactions, which limits the in-depth understanding of atmospheric chemical mechanisms. Therefore, it is urgent to develop outdoor smoke chamber simulation technology in order to obtain real and effective atmospheric chemical parameters and make up for the shortcomings of existing technology. It is urgent to develop a device and method for real-time simulation of real atmospheric chemical reactions. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to address the deficiencies of the above-mentioned existing technologies and provide a device and experimental method for real-time simulation of chemical reactions in the actual environment. The device can effectively solve the problems of inaccurate test results due to particulate matter adhering to the inner wall and the inability to simulate and detect the real atmospheric environment in real time for a long time.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: a device for real-time simulation of atmospheric chemical reactions in an actual environment, characterized in that it includes a main reactor, which includes an outer negative pressure refrigeration chamber, a middle transverse reaction chamber and an inner sample gas infiltration and diffusion chamber from the outside to the inside, a polymethyl methacrylate plate and a light reflecting plate are arranged on the outer negative pressure refrigeration chamber, a negative pressure pump, an electrostatic eliminator, a heat exchanger and a turbulent fan are arranged in the outer negative pressure refrigeration chamber, a cylindrical membrane cabin made of polytetrafluoroethylene is arranged on the middle transverse reaction chamber, a driving component for driving the middle transverse reaction chamber to rotate is installed axially in the middle transverse reaction chamber, a permeable membrane is arranged on the inner sample gas infiltration and diffusion chamber, the permeable membrane is in contact with the middle transverse reaction chamber, the front and rear ends of the inner sample gas infiltration and diffusion chamber are connected to the airflow component, and the main reactor is connected to a refrigeration system, a detection system, a seed aerosol injection system and a control box.

[0007] Preferably, the outer negative pressure refrigeration chamber is a sealed box in a cubic shape, and the outer negative pressure refrigeration chamber includes a main frame, and the main frame includes a stainless steel frame and an outer frame flange. A polymethacrylic plate is installed on the stainless steel frame through the outer frame flange to achieve a sealing effect. The polymethacrylic plate has ultraviolet light transmission properties. Reflective plates are set at the bottom and lower side walls of the outer negative pressure refrigeration chamber, and the reflective plates include a reflective aluminum plate, an expanded polytetrafluoroethylene reflective pad and a polytetrafluoroethylene film arranged from the inside to the outside.

[0008] Preferably, the middle-level transverse reaction chamber comprises a circular frame and a membrane capsule, the membrane capsule being fixed to the circular frame. The drive assembly comprises a motor, a rotating shaft, and a fixed shaft, the fixed shaft being fixedly mounted to the main frame. The rotating shaft is connected to the fixed shaft via a slewing bearing, the rotating shaft being fixedly connected to the circular frame, and the rotating shaft is transmission-connected to the output shaft of the motor. Both the rotating shaft and the fixed shaft are hollow structures for connecting the seed-injection aerosol system and the middle-level transverse reaction chamber.

[0009] Preferably, the inner layer sample gas infiltration diffusion cavity is provided with an airflow component for the actual ambient atmosphere to enter, the inner layer sample gas infiltration diffusion cavity includes a diffusion support frame and a diffusion film, the diffusion film is an expanded polytetrafluoroethylene film, the diffusion film is arranged on a cylindrical diffusion support frame, the airflow component includes a rainproof sleeve, a filter cartridge and an air intake guide pipe, the filter cartridge is vertically fixed on the main frame, a sampling hole is provided on the filter cartridge, a rainproof sleeve is provided on the top of the filter cartridge, and the filter cartridge is connected to the inner layer sample gas infiltration diffusion cavity through the air intake guide pipe.

[0010] Preferably, one end of the inner layer sample gas permeation diffusion cavity is connected to the air inlet guide tube, and the other end of the inner layer sample gas permeation diffusion cavity is connected to the sampling air pump through the air outlet guide tube, and a low pressure drop flow meter is provided on the air outlet guide tube.

[0011] Preferably, the middle-layer transverse reaction chamber is at a positive pressure with a pressure difference of less than 30 Pa relative to the outer-layer negative-pressure refrigeration chamber.

[0012] Preferably, a controller is provided in the control box, and the control box is connected to a motor, a negative pressure pump, a sampling air pump, a seed injection aerosol system, a refrigeration system and a detection system. A cold air sheet connected to the refrigeration system is provided in the outer negative pressure refrigeration cavity. The seed injection aerosol system includes an aerosol generator, a drying tube and a particle sifter. The detection system includes nitrogen oxides, sulfur dioxide and ozone analyzers, a photon flux detector, an aerosol generator, an ozone generator, a scanning mobility particle size spectrometer, and an atmospheric pressure soft ionization ionization mass spectrometer.

[0013] Preferably, the rotating shaft is connected to the fixed shaft through a bearing, the rotating shaft is fixedly connected to the diffusion support frame through a diffusion support frame fixing groove, a bearing support cylinder for limiting the bearing is provided on the inner side of the rotating shaft, a sealing gasket is provided on the rotating shaft, and a particle outlet is provided on the rotating shaft; one end of the fixed shaft is fixedly mounted on the stainless steel frame through a fixed shaft base, a reaction gas channel, a seed particle channel and an environmental sample gas channel are provided on the fixed shaft base, an environmental sample gas channel outlet is provided on the fixed shaft, and an O-ring is provided on the fixed shaft.

[0014] A method for simulating a chemical reaction in the atmosphere in real time using a device for simulating a chemical reaction in the atmosphere in real time comprises the following steps:

[0015] S1. Select observation points: Select atmospheric observation points. The points need to have sufficient lighting. Debug and determine the detailed test plan to ensure that the points where the sample gas is to be measured meet the representative requirements of the real atmospheric environment.

[0016] S2. Cleaning and installing the reactor: Before installation, bake the membrane cabin of the middle horizontal reaction chamber at 180°C for 12 hours to remove volatile organic compounds remaining on the surface of the material; before the experiment, use ultrapure water to clean the inside and outside of the polymethacrylic plate, and use dust-free paper soaked in alcohol to wipe the surface of the polytetrafluoroethylene film of the reflective plate to increase light transmittance; regularly introduce high-concentration ozone into the middle horizontal reaction chamber through the air flow duct to make the ozone concentration reach above 5ppm, and continue for 12 hours or more to oxidize and clean the chemical substances attached to the wall surface in the middle horizontal reaction chamber; after cleaning, install the reactor at the observation point;

[0017] S3. Check the air tightness of the main reactor: block the air inlet and outlet, and continuously inject gas into the middle horizontal reaction chamber at 1L / min. The membrane cabin gradually bulges, indicating that the air tightness is good;

[0018] S4. Connect the pipeline and debug the flow: adjust the voltage of the sampling pump to achieve the set sampling flow;

[0019] S5, temperature control and adjustment: using a temperature sensor to detect the device temperature, turning on the refrigeration system (6) and adjusting the temperature so that the reactor temperature reaches the target value;

[0020] S6. Control and regulate the pressure difference: adjust the pressure difference between the middle horizontal reaction chamber and the outer negative pressure refrigeration chamber to reach a set threshold, so as to ensure that the membrane cabin of the middle horizontal reaction chamber is full and the volume is constant;

[0021] S7. Determine the gas exchange rate: Inject a high concentration of a marker gas (such as carbon monoxide) into the inlet duct. Use a gas detector to measure the concentration change in the middle horizontal reaction chamber. Quantitatively calculate the gas diffusion exchange rate by taking the differential of the concentration with respect to time. Adjust the gas exchange rate and analyze the reaction process under different oxidizing conditions.

[0022] S8. Determine the residence time: introduce a marker gas (such as carbon monoxide), use a gas analyzer corresponding to the marker gas to detect the real-time changes of the marker gas in the middle horizontal reaction chamber, perform curve fitting with time, and obtain the residence time of the gas, and further calculate the half-life;

[0023] S9, driving the middle horizontal reaction chamber to rotate through the control box at a speed of less than 10 rpm;

[0024] S10. The main reactor continuously extracts atmospheric ambient air at a constant flow rate. The extracted sample gas passes through the rainproof sleeve, filter cartridge, and air inlet guide tube, enters the inner layer sample gas permeation diffusion chamber, and is filtered by the diffusion membrane after filtering out particulate matter before diffusing into the middle layer transverse reaction chamber. Atmospheric chemistry simulation is divided into two modes: one is without adding additional reaction gas, and the second is with adding additional reaction gas. The additional reaction gas is directly introduced into the middle layer transverse reaction chamber through the air inlet guide tube.

[0025] S11. Simulating daytime atmospheric chemistry: The main reactor is placed in sunlight. The ambient air is filtered through a filter cartridge to remove particulate matter. The particulate-free gas enters the inner sample gas diffusion chamber. Further, the gas diffuses into the middle lateral reaction chamber. Due to light radiation, hydroxyl and peroxyhydroxyl radicals are generated. The gas entering the middle lateral reaction chamber undergoes multi-generation oxidation reactions, generating reaction oxidation products and secondary oxidation products, and new particulate matter is generated along with the physical process.

[0026] S12. Detection of reactants and reaction products: The detection system is connected to the middle-layer transverse reaction chamber, and the detection system detects the components and concentrations of the reactants and products of atmospheric chemistry occurring in the membrane chamber in real time;

[0027] S13. Calculate the reaction process: Based on the chemical molecular formula of the reaction products detected by the detection system, identify and screen species, incorporate them into the chemical theoretical calculation model, input the parameters measured in the experiment into the chemical theoretical calculation model, use the chemical theoretical calculation model to calculate the concentration of free radicals in the middle-level lateral reaction cavity, oxidation products, reaction products of different pathways, and oxidation process parameters, interpret the measured results of laboratory simulation, and explore the characteristics of the chemical mechanism.

[0028] Compared with the prior art, the present invention has the following advantages:

[0029] 1. The present invention sets a micro-positive pressure to drive the membrane cabin of the middle horizontal reaction chamber to be full, with a constant volume, enhanced circulation, no dead angle airflow, and conducive to rotation to generate laminar flow.

[0030] 2. The present invention diffuses gas axially to the middle horizontal reaction chamber through the inner horizontal sample gas penetration chamber. The gas undergoes photochemical reaction under natural light. The flow reactor continuously collects large flow rates of ambient air to simulate and detect atmospheric chemical reactions. The design is scientific and reasonable, the use effect is good, and the detection effect is accurate.

[0031] 3. The present invention drives the middle-layer horizontal reaction chamber to rotate slowly through a driving component, so that the air flow in the chamber produces axial laminar flow, thereby reducing the wall loss of particles caused by gravity. The static electricity generated at the interface of the polytetrafluoroethylene membrane and the polymethacrylic plate is evenly eliminated through the static eliminator, thereby reducing the wall loss of nano-scale particles caused by electrostatic adsorption.

[0032] 4. The present invention can operate 24 hours a day to comprehensively observe the atmospheric chemical reaction process during the day and at night. The device has good sealing performance, is wind-proof and rain-proof, and can operate year-round to further simulate and compare the differences in atmospheric chemical reactions in different seasons.

[0033] 5. The device of the present invention is small in size and convenient for transportation and carrying. It is suitable for observation of complex points in multiple scenarios. It can flexibly adjust the temperature and vacuum degree in the main reactor to simulate real atmospheric chemical reactions in the closest way.

[0034] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0036] Figure 2 It is a schematic diagram of the three-dimensional structure of the main reactor of the present invention.

[0037] Figure 3 It is a side structural schematic diagram of the main reactor in the present invention.

[0038] Figure 4 It is a fixed-axis stereogram of the main reactor in the present invention.

[0039] Figure 5 It is a three-dimensional diagram of the rotating shaft of the main reactor in the present invention.

[0040] Figure 6 This is a comparison chart of volatile organic compounds in the main reactor and the ambient atmosphere in the present invention.

[0041] Description of reference numerals:

[0042] 1. Main frame; 2. Outer negative pressure refrigeration chamber; 3. Middle-level horizontal reaction chamber; 4. Inner layer sample gas permeates the diffusion cavity; 5. Control box; 6. Refrigeration system; 7. Detection system; 8. Seed injection aerosol system; 1-1, stainless steel frame; 1-2, outer frame flange; 1-3, polymethacrylic acid board; 1-4, internal stent; 1-5, polymethacrylic acid strips; 2-1. Static elimination meter; 2-2, light reflecting plate; 2-3, spoiler fan; 2-4, negative pressure vacuum pump; 3-1, membrane cabin; 3-2, round frame support frame; 3-3, round frame; 3-4, electric motor; 3-5, rotating shaft; 3-6, fixed axis; 3-7, connecting shaft; 4-1, Rainproof sleeve; 4-2, filter cartridge; 4-3. Intake guide pipe 4-4. Sample gas penetrates the diffusion chamber; 4-4-1, diffusion support frame; 4-4-2. Expanded polytetrafluoroethylene membrane 4-5. Flow meter; 4-6, sampling air pump; 6-1, Chiller; 6-2, heat sink; 8-1, Particle generator; 8-2, drying tube; 8-3, particle sifter; 3-5-1. Diffusion support frame fixing slot 3-5-2, bearings; 3-5-3, bearing support cylinder; 3-5-4, sealing gasket; 3-5-5, particle outlet; 3-6-1, Environmental sample gas channel; 3-6-2, seed particle channel; 3-6-3, reaction gas channel; 3-6-4, fixed axis base; 3-6-5, O-ring; 3-6-6. Environmental sample gas channel outlet. 1. Main frame; 2. Outer negative pressure refrigeration chamber; 3. Middle-level horizontal reaction chamber; 4. Inner layer sample gas permeates the diffusion cavity; 5. Control box; 6. Refrigeration system; 7. Detection system; 8. Seed injection aerosol system; 1-1, stainless steel frame; 1-2, outer frame flange; 1-3, polymethacrylic acid board; 1-4, internal stent; 1-5, polymethacrylic acid strips; 2-1. Static elimination meter; 2-2, light reflecting plate; 2-3, spoiler fan; 2-4, negative pressure vacuum pump; 3-1, membrane cabin; 3-2, round frame support frame; 3-3, round frame; 3-4, electric motor; 3-5, rotating shaft; 3-6, fixed axis; 3-7, connecting shaft; 4-1, Rainproof sleeve; 4-2, filter cartridge; 4-3. Intake guide pipe 4-4. Sample gas penetrates the diffusion chamber; 4-4-1, diffusion support frame; 4-4-2. Expanded polytetrafluoroethylene membrane 4-5. Flow meter; 4-6, sampling air pump; 6-1, Chiller; 6-2, heat sink; 8-1, Particle generator; 8-2, drying tube; 8-3, particle sifter; 3-5-1. Diffusion support frame fixing slot 3-5-2, bearings; 3-5-3, bearing support cylinder; 3-5-4, sealing gasket; 3-5-5, particle outlet; 3-6-1, Environmental sample gas channel; 3-6-2, seed particle channel; 3-6-3, reaction gas channel; 3-6-4, fixed axis base; 3-6-5, O-ring; 3-6-6. Environmental sample gas channel outlet. DETAILED DESCRIPTION

[0043] Example 1

[0044] like Figures 1 to 5 As shown, this embodiment provides a device for simulating atmospheric chemical reactions in an actual environment in real time, including a main reactor, which includes, from the outside to the inside, an outer negative pressure refrigeration chamber 2, a middle transverse reaction chamber 3 and an inner sample gas infiltration and diffusion chamber 4. A polymethyl methacrylate plate 1-3 and a reflective light plate 2-2 are provided on the outer negative pressure refrigeration chamber 2. A negative pressure pump 2-4, an electrostatic eliminator 2-1 and a turbulent fan 2-3 are provided in the outer negative pressure refrigeration chamber 2. A membrane cabin 3-1 made of polytetrafluoroethylene is provided on the middle transverse reaction chamber 3. A driving component for driving the middle transverse reaction chamber 3 to rotate is installed on the middle transverse reaction chamber 3. An airflow component is provided on the inner sample gas infiltration and diffusion chamber 4. The main reactor is connected to a refrigeration system 6, a detection system 7, a seed aerosol injection system 8 and a control box 5.

[0045] In this embodiment, the outer negative pressure refrigeration chamber 2 is a sealed box in the shape of a cube. The outer negative pressure refrigeration chamber 2 includes a main frame 1. The main frame 1 includes a stainless steel frame 1-1 and an outer frame flange 1-2. A polymethacrylic plate 1-3 is installed on the stainless steel frame 1-1 through the outer frame flange 1-2 to achieve a sealing effect. The polymethacrylic plate 1-3 has ultraviolet light transmission properties. A reflective plate 2-2 is set at the bottom and lower part of the side wall of the outer negative pressure refrigeration chamber 2. The reflective plate 2-2 includes a reflective aluminum plate, an expanded polytetrafluoroethylene reflective pad and a polytetrafluoroethylene film arranged from the inside to the outside.

[0046] In this embodiment, the middle-level transverse reaction chamber 3 includes a circular frame 3-3 and a membrane capsule 3-1. The membrane capsule 3-1 is fixed to the circular frame 3-3. The drive assembly includes a motor 3-4, a rotating shaft 3-5, and a fixed shaft 3-6. The fixed shaft 3-6 is fixedly mounted on the main frame 1. The rotating shaft 3-5 is connected to the fixed shaft 3-6 via a slewing bearing. The rotating shaft 3-5 is fixedly connected to the circular frame 3-3 and is transmission-connected to the output shaft of the motor 3-4. The rotating shaft 3-5 and the fixed shaft 3-6 are both hollow structures for connecting the seed injection aerosol system 8 and the middle-level transverse reaction chamber 3.

[0047] In this embodiment, the inner layer sample gas infiltration diffusion chamber 4 is provided with an airflow component for the actual ambient atmosphere to enter, and the inner layer sample gas infiltration diffusion chamber 4 includes a diffusion support frame 4-4-1 and a diffusion film 4-4-2, and the diffusion film 4-4-2 is an expanded polytetrafluoroethylene film, and the diffusion film 4-4-2 is arranged on the cylindrical diffusion support frame 4-4-1, and the airflow component includes a rainproof sleeve 4-1, a filter cartridge 4-2 and an air intake guide pipe 4-3, and the filter cartridge 4-2 is vertically fixed on the main frame 1, and a sampling hole is provided on the filter cartridge 4-2, and a rainproof sleeve 4-1 is provided on the top of the filter cartridge 4-2, and the filter cartridge 4-2 is connected to the inner layer sample gas infiltration diffusion chamber 4 through the air intake guide pipe 4-3.

[0048] In this embodiment, the rotating shaft 3-5 is connected to the fixed shaft 3-6 through the bearing 3-5-2, and the rotating shaft 3-5 is fixedly connected to the diffusion support frame 4-4-1 through the diffusion support frame fixing groove 3-5-1. A bearing support cylinder 3-5-3 for limiting the bearing 3-5-2 is provided on the inner side of the rotating shaft 3-5, a sealing gasket 3-5-4 is provided on the rotating shaft 3-5, and a particle outlet 3-5-5 is provided on the rotating shaft 3-5; one end of the fixed shaft 3-6 is fixedly installed on the stainless steel frame 1-1 through a fixed shaft base 3-6-4, and a reaction gas channel 3-6-3, a seed particle channel 3-6-2 and an environmental sample gas channel 3-6-1 are provided on the fixed shaft base 3-6-4, an environmental sample gas channel outlet 3-6-6 is provided on the fixed shaft 3-6, and an O-ring 3-6-5 is provided on the fixed shaft 3-6.

[0049] In this embodiment, one end of the inner layer sample gas permeation diffusion chamber 4 is connected to the air inlet guide tube 4-3, and the other end of the inner layer sample gas permeation diffusion chamber 4 is connected to the sampling air pump 4-6 through the air outlet guide tube, and a low pressure drop flowmeter 4-5 is provided on the air outlet guide tube.

[0050] In this embodiment, the middle-layer transverse reaction chamber 3 is at a positive pressure with a pressure difference of less than 30 Pa relative to the outer-layer negative-pressure refrigeration chamber 2 .

[0051] In this embodiment, a controller is set in the control box 5, and the control box 5 is connected to the motor 3-4, the negative pressure pump 2-4, the sampling air pump 4-6, the seed injection aerosol system 8, the refrigeration system 6 and the detection system 7. The outer negative pressure refrigeration cavity 2 is provided with a cold air sheet 6-2 connected to the refrigeration system 6. The seed injection aerosol system 8 includes an aerosol generator 8-1, a drying tube 8-2 and a particle sifter 8-3. The detection system 7 includes NOx, SO2 and O3 analyzers, a photon flux detector, an aerosol generator, an O3 generator, a scanning mobility particle size spectrometer, and an atmospheric pressure soft ionization ionization mass spectrometer.

[0052] Example 2

[0053] This embodiment provides a method for simulating a chemical reaction in the atmosphere in real time using a device for simulating a chemical reaction in the atmosphere in real time, including the following steps:

[0054] S1. Select observation points: Select atmospheric observation points. The points need to have sufficient lighting. Debug and determine the detailed test plan to ensure that the points where the sample gas is to be measured meet the representative requirements of the real atmospheric environment.

[0055] S2. Cleaning and installing the reactor: In the early stage of installation, bake the membrane cabin 3-1 of the middle horizontal reaction chamber 3 at 180°C for 12 hours to remove volatile organic compounds remaining on the surface of the material; in the early stage of the experiment, use ultrapure water to clean the inside and outside of the polymethacrylic plate 1-3, and use dust-free paper soaked in alcohol to wipe the surface of the polytetrafluoroethylene film of the reflective plate 2-2 to increase light transmittance; regularly introduce high-concentration ozone into the middle horizontal reaction chamber 3 through the air inlet guide pipe 4-3 to make the ozone concentration reach above 5ppm, and continue for 12 hours or more to oxidize and clean the chemical substances attached to the wall surface of the middle horizontal reaction chamber 3; after cleaning, install the reactor at the observation point;

[0056] S3. Check the air tightness of the main reactor: block the air inlet and outlet, and continuously inject gas into the middle horizontal reaction chamber 3 at 1 L / min. The membrane cabin 3-1 gradually expands, indicating good air tightness.

[0057] S4. Connect the pipeline and adjust the flow rate: adjust the voltage of the sampling gas pump 4-6 to achieve the set sampling flow rate;

[0058] S5, temperature control and adjustment: Use the temperature sensor to detect the device temperature, turn on the refrigeration system 6 and adjust the temperature so that the reactor temperature reaches the target value;

[0059] S6. Control and regulate the pressure difference: adjust the pressure difference between the middle transverse reaction chamber 3 and the outer negative pressure refrigeration chamber 2 to reach a set threshold, ensuring that the membrane cabin of the middle transverse reaction chamber 3 is full and drum-shaped, and the volume reaches a constant state;

[0060] S7. Determine the gas exchange rate: Inject a high concentration of a marker gas, such as carbon monoxide, into the inlet guide tube 4-3. Use a gas detector to measure the concentration change in the middle horizontal reaction chamber 3. Quantitatively calculate the gas diffusion exchange rate by differentiating the concentration with respect to time. Adjust the gas exchange rate and analyze the reaction process under different oxidizing conditions.

[0061] S8. Determine the residence time: introduce a marker gas such as carbon monoxide, and use a gas analyzer corresponding to the marker gas to detect the real-time changes of the marker gas in the middle horizontal reaction chamber 3, perform curve fitting with time, and obtain the residence time of the gas, and further calculate the half-life;

[0062] S9, driving the middle horizontal reaction chamber 3 to rotate through the control box 5, with a speed of less than 10 rpm;

[0063] S10. The main reactor continuously extracts atmospheric ambient air at a constant flow rate. The extracted sample gas passes through the rainproof sleeve 4-1, the filter cartridge 4-2, and the air inlet guide tube 4-3, enters the inner layer sample gas penetration diffusion chamber 4, and is filtered by the diffusion membrane 4-4-2. After the particulate matter is diffused, it diffuses into the middle layer transverse reaction chamber 3. There are two modes of atmospheric chemical simulation: one is without adding additional reaction gas, and the second is with adding additional reaction gas. The additional reaction gas is directly introduced into the middle layer transverse reaction chamber 3 through the air inlet guide tube 4-3.

[0064] S11. Simulating daytime atmospheric chemistry: The main reactor is placed in sunlight. The ambient air is filtered through the filter cartridge 4-2 to remove particulate matter. The particulate-free gas enters the inner sample gas permeation diffusion chamber 4. The gas further diffuses into the middle transverse reaction chamber 3. Due to light radiation, hydroxyl and peroxyhydroxyl radicals are generated. The gas entering the middle transverse reaction chamber 3 undergoes multi-generation oxidation reactions, generating reaction oxidation products and secondary oxidation products, and new particulate matter is generated in conjunction with the physical process.

[0065] S12, detection of reactants and reaction products: the detection system 7 is connected to the middle horizontal reaction chamber 3, and the detection system 7 detects the components and concentrations of the reactants and products of atmospheric chemistry occurring in the membrane cabin 3-1 in real time. Figure 6 As shown;

[0066] S13. Calculate the reaction process: Based on the chemical molecular formula of the reaction products detected by the detection system 7, identify and screen the species, incorporate them into the chemical theoretical calculation model, input the parameters measured in the experiment into the chemical theoretical calculation model, use the chemical theoretical calculation model to calculate the concentration of free radicals, oxidation products, reaction products of different pathways, and oxidation process parameters in the middle-level horizontal reaction chamber 3, interpret the actual measurement results of the laboratory simulation, and explore the characteristics of the chemical mechanism.

[0067] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent variation made to the above embodiment based on the essence of the invention technology shall still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A device for simulating chemical reactions in the actual atmosphere in real time, characterized in that: The invention comprises a main reactor, wherein the main reactor comprises an outer negative pressure refrigeration chamber (2), a middle transverse reaction chamber (3) and an inner sample gas permeation diffusion chamber (4) in sequence from the outside to the inside; the outer negative pressure refrigeration chamber (2) provides a negative pressure, temperature control, enhanced light, and static-free environment; a polymethyl methacrylate plate (1-3) and a light reflecting plate (2-2) are arranged on the outer negative pressure refrigeration chamber (2); a negative pressure pump (2-4), an anti-static meter (2-1) and a turbulent fan (2-3) are arranged in the outer negative pressure refrigeration chamber (2) The middle-layer transverse reaction chamber (3) is provided with a membrane cabin (3-1) made of polytetrafluoroethylene, and the middle-layer transverse reaction chamber (3) is provided with a driving component for driving the middle-layer transverse reaction chamber (3) to rotate; the inner-layer sample gas permeation diffusion chamber (4) permeates and diffuses gas into the middle-layer transverse reaction chamber (3), and the inner-layer sample gas permeation diffusion chamber (4) is provided with an airflow component; the main reactor is connected to a refrigeration system (6), a detection system (7), a seed aerosol injection system (8) and a control box (5).

2. The device for simulating chemical reactions in an actual environment in real time according to claim 1, characterized in that: The outer negative pressure refrigeration chamber (2) is a sealed box in the shape of a cube that is transparent to ultraviolet light. The outer negative pressure refrigeration chamber (2) comprises a main frame (1), and the main frame (1) comprises a stainless steel frame (1-1) and an outer frame flange (1-2). A polymethyl methacrylate plate (1-3) is installed on the stainless steel frame (1-1) through the outer frame flange (1-2) to achieve a sealing effect. The polymethyl methacrylate plate (1-3) has the property of being transparent to ultraviolet light. A reflective plate (2-2) is provided at the bottom and the lower part of the side wall of the outer negative pressure refrigeration chamber (2). The reflective plate (2-2) comprises a reflective aluminum plate, an expanded polytetrafluoroethylene reflective pad, and a polytetrafluoroethylene film arranged from the inside to the outside.

3. The device for simulating chemical reactions in the actual atmosphere in real time according to claim 1, characterized in that: The middle-layer transverse reaction chamber (3) includes a circular frame (3-3) and a membrane cabin (3-1), the membrane cabin (3-1) is fixed on the circular frame (3-3), the driving assembly includes a motor (3-4), a rotating shaft (3-5) and a fixed shaft (3-6), the fixed shaft (3-6) is fixedly mounted on the main frame (1), the rotating shaft (3-5) is connected to the fixed shaft (3-6) via a rotary bearing, the rotating shaft (3-5) is fixedly connected to the circular frame (3-3), the rotating shaft (3-5) is transmission-connected to the output shaft of the motor (3-4), and the rotating shaft (3-5) and the fixed shaft (3-6) are both hollow structures for connecting the seed injection aerosol system (8) and the middle-layer transverse reaction chamber (3).

4. The device for simulating chemical reactions in an actual environment in real time according to claim 1, characterized in that: The inner layer sample gas infiltration diffusion chamber (4) is provided with an airflow component for continuous entry of actual ambient atmosphere, the inner layer sample gas infiltration diffusion chamber (4) comprises a diffusion support frame (4-4-1) and a diffusion film (4-4-2), the diffusion film (4-4-2) is an expanded polytetrafluoroethylene film, the diffusion film (4-4-2) is provided on the cylindrical diffusion support frame (4-4-1), the airflow component comprises a rainproof sleeve (4-1), a filter cartridge (4-2) and an air intake guide pipe (4-3), the filter cartridge (4-2) is vertically fixed on the main frame (1), a sampling hole is provided on the filter cartridge (4-2), a rainproof sleeve (4-1) is provided on the top of the filter cartridge (4-2), and the filter cartridge (4-2) is connected to the inner layer sample gas infiltration diffusion chamber (4) through the air intake guide pipe (4-3).

5. The device for simulating chemical reactions in the actual atmosphere in real time according to claim 4, characterized in that: The gas permeates and diffuses from the diffusion film (4-4-2) into the interior of the middle-layer transverse reaction chamber (3); one end of the inner-layer sample gas permeation diffusion chamber (4) is connected to the air inlet guide tube (4-3); the other end of the inner-layer sample gas permeation diffusion chamber (4) is connected to the sampling air pump (4-6) through the air outlet guide tube; and a low-pressure drop flowmeter (4-5) is provided on the air outlet guide tube.

6. The device for simulating chemical reactions in the actual atmosphere in real time according to claim 1, characterized in that: The middle-layer transverse reaction chamber (3) presents a positive pressure with a pressure difference of less than 30 Pa relative to the outer-layer negative-pressure refrigeration chamber (2), and the pressure difference drives the membrane cabin (3-1) to be round and full, with a constant volume.

7. The device for simulating chemical reactions in the actual atmosphere in real time according to claim 3, characterized in that: The control box (5) is provided with a controller, and the control box (5) is connected to a motor (3-4), a negative pressure pump (2-4), a sampling air pump (4-6), a seed injection aerosol system (8), a refrigeration system (6) and a detection system (7). The outer negative pressure refrigeration cavity (2) is provided with a cold air sheet (6-2) connected to the refrigeration system (6). The seed injection aerosol system (8) includes an aerosol generator (8-1), a drying tube (8-2) and a particle sifter (8-3). The detection system (7) includes a NOx, SO2 and O3 analyzer, a photon flux detector, an aerosol Generator, O3 generator, scanning mobility particle size spectrometer, atmospheric pressure soft ionization mass spectrometer, the rotating shaft (3-5) is connected to the fixed shaft (3-6) through a bearing (3-5-2), the rotating shaft (3-5) is fixedly connected to the diffusion support frame (4-4-1) through a diffusion support frame fixing groove (3-5-1), a bearing support cylinder (3-5-3) for limiting the bearing (3-5-2) is provided on the inner side of the rotating shaft (3-5), a sealing gasket (3-5-4) is provided on the rotating shaft (3-5), and a particle outlet (3-5-5) is opened on the rotating shaft (3-5); One end of the fixed shaft (3-6) is fixedly mounted on the stainless steel frame (1-1) via a fixed shaft base (3-6-4); a reaction gas channel (3-6-3), a seed particle channel (3-6-2), and an environmental sample gas channel (3-6-1) are provided on the fixed shaft base (3-6-4); an environmental sample gas channel outlet (3-6-6) is provided on the fixed shaft (3-6); and an O-type sealing ring (3-6-5) is provided on the fixed shaft (3-6).

8. A method for simulating a chemical reaction in the atmosphere in real time using the device for simulating a chemical reaction in the atmosphere in real time according to any one of claims 1 to 7, characterized in that: The following steps are included: S1. Select observation points: Select atmospheric observation points. The points need to have sufficient lighting. Debug and determine the detailed test plan to ensure that the points where the sample gas is to be measured meet the representative requirements of the real atmospheric environment. S2. Cleaning and installing the main reactor: In the early stage of installation, the membrane cabin (3-1) of the middle horizontal reaction chamber (3) is baked at 180°C for 12 hours to remove the volatile organic compounds remaining on the surface of the material; in the early stage of the experiment, ultrapure water is used to clean the inside and outside of the polymethyl methacrylate plate (1-3), and the surface of the polytetrafluoroethylene film of the reflective plate (2-2) is wiped with dust-free paper soaked in alcohol to increase the light transmittance; high-concentration ozone is regularly introduced into the middle horizontal reaction chamber (3) through the air inlet guide pipe (4-3) to make the ozone concentration reach above 5ppm, and the ozone concentration is continuously for 12 hours or more to oxidize and clean the chemical substances attached to the wall surface of the middle horizontal reaction chamber (3); after cleaning, the main reactor is installed at the observation point; S3. Check the air tightness of the main reactor: block the air inlet and outlet, and continuously inject 1L / min of gas into the middle horizontal reaction chamber (3). The membrane cabin (3-1) gradually swells, indicating that the air tightness is good; S4. Connect the pipeline and adjust the flow rate: adjust the voltage of the sampling air pump (4-6) to achieve the set sampling flow rate; S5, temperature control and adjustment: using a temperature sensor to detect the device temperature, turning on the refrigeration system (6) and adjusting the temperature so that the temperature of the main reactor reaches the target value; S6, control and adjust the pressure difference: adjust the pressure difference between the middle horizontal reaction chamber (3) and the outer negative pressure refrigeration chamber (2) to reach the set threshold value, ensure that the membrane cabin of the middle horizontal reaction chamber (3) is in a drum-like full state and the volume reaches a constant state; S7. Determine the gas exchange rate: inject a high concentration of identification gas into the air inlet guide tube (4-3), use a gas detector to measure the concentration change in the middle horizontal reaction chamber (3), quantitatively calculate the gas diffusion exchange rate by the differential of the concentration with respect to time, adjust the gas exchange rate, and analyze the reaction process under different oxidizing conditions; S8. Determine the residence time: introduce the marker gas, detect the real-time change of the marker gas in the middle horizontal reaction chamber (3) by using a gas analyzer corresponding to the marker gas, perform curve fitting with time, obtain the residence time of the gas, and further calculate the half-life; S9, driving the middle horizontal reaction chamber (3) to rotate via the control box (5), with the rotation speed being less than 10 rpm; S10, the main reactor continuously extracts atmospheric ambient air at a constant flow rate, and the extracted sample gas passes through the rainproof sleeve (4-1), the filter cartridge (4-2) and the air inlet guide tube (4-3) in sequence, enters the inner layer sample gas penetration diffusion chamber (4), and is filtered by the diffusion film (4-4-2) to remove particulate matter, and then diffuses into the middle layer transverse reaction chamber (3); atmospheric chemical simulation is divided into two modes, one is not adding additional reaction gas, and the second is adding additional reaction gas, and the additional reaction gas is directly introduced into the middle layer transverse reaction chamber (3) through the air inlet guide tube (4-3); S11. Simulating daytime atmospheric chemistry: The main reactor is placed in sunlight. The ambient air is filtered through the filter cartridge (4-2) to remove particulate matter. The particulate-free gas enters the inner layer sample gas penetration diffusion chamber (4). Further, the gas diffuses into the middle layer transverse reaction chamber (3). Due to light radiation, hydroxyl radicals and peroxyhydroxyl radicals are generated. The gas entering the middle layer transverse reaction chamber (3) undergoes multi-generation oxidation reactions to generate reaction oxidation products and secondary oxidation products, and new particulate matter is generated along with the physical process. S12. Detection of reactants and reaction products: The detection system (7) is connected to the middle-layer transverse reaction chamber (3), and the detection system (7) detects in real time the components and concentrations of the reactants and products of atmospheric chemistry occurring in the membrane cabin (3-1); S13. Calculate the reaction process: Based on the chemical molecular formula of the reaction products detected by the detection system (7), identify and screen the species, incorporate them into the chemical theoretical calculation model, input the parameters measured in the experiment into the chemical theoretical calculation model, use the chemical theoretical calculation model to calculate the concentration of free radicals, oxidation products, reaction products of different pathways, and oxidation process parameters in the middle-level transverse reaction chamber (3), interpret the measured results of the laboratory simulation, and explore the characteristics of the chemical mechanism.

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