Ozone generation rate monitoring system and monitoring method

Abstract

The invention is suitable for the technical field of pollutant monitoring, and provides an ozone generation rate monitoring system and method, the system comprises a zero gas generation module, a gas distribution module, a multi-mode combination switching valve, a free radical generation source, a chemical amplification cavity and a detection module; the gas distribution module is used for inputting standard reactant gas with different components and sample gas sample; the input end of the multi-mode combined switching valve is connected with the zero gas generation module and the gas distribution module; a first output end of the multi-mode combined switching valve is connected with a gas inlet of the free radical generation source, a second output end is connected with a gas inlet of the chemical amplification cavity, and a third output end is connected with a gas outlet of the chemical amplification cavity; an exhaust port of the free radical generation source is connected with an air inlet of the chemical amplification cavity; and the exhaust port of the chemical amplification cavity is also connected with the detection module. According to the method, the ozone photochemical generation rate is directly obtained by accurately measuring data such as the total peroxy free radical concentration, the detection precision is higher, and the speed is higher.

Description

Technical Field

[0001] The present invention belongs to the technical field of pollutant monitoring, and in particular relates to an ozone generation rate monitoring system and a monitoring method. Background Art

[0002] Ambient atmospheric ozone 3 It is composed of nitrogen oxides (NOx=NO+NO 2 A typical secondary pollutant generated by photochemical reactions of precursors such as 3 The concentration is affected by photochemical generation, deposition, and regional transport, and O 3 The formation of O 3 It is difficult to quantify the generation and accurately prevent pollution. Therefore, quantitative monitoring of the ozone photochemical generation rate is helpful to study the mechanism of ozone generation, quantify O 3 The contribution of photochemical generation and transport, as well as the analysis and judgment of the contribution of nitrogen oxides, provide key support for the prevention and control of ozone pollution.

[0003] The existing ozone monitoring system mainly monitors ozone concentration and photochemical oxidant (Ox) generation. There are deficiencies in the quantitative research on the photochemical generation rate of ozone, and there is a lack of direct monitoring system for photochemical generation rate and methods for evaluating the contribution of nitrogen oxides. In addition, the current ozone generation rate is mainly obtained by model simulation, not actual measurement value, which has certain errors and cannot accurately quantify the contribution of photochemical reaction process to O 3 At the same time, the existing ozone generation rate monitoring systems in the industry often monitor the generation rate of photochemical oxidants (Ox), that is, the net generation rate of ozone. There is a lack of direct monitoring of the photochemical generation rate of ozone, and it is impossible to effectively guide the control of atmospheric ozone pollution generation.

[0004] Therefore, a new method and device for detecting ozone generation rate needs to be studied. Summary of the invention

[0005] The purpose of the embodiments of the present application is to provide an ozone generation rate monitoring system, aiming to solve the problems of errors in existing ozone photochemical generation rate simulation results and gaps in online monitoring equipment.

[0006] The embodiment of the present application is implemented by providing an ozone generation rate monitoring system, the system comprising:

[0007] Zero gas generation module, gas distribution module, multi-mode combination switching valve, free radical generation source, chemical amplification chamber and detection module;

[0008] The zero gas generation module is used to obtain zero gas and input it into the system;

[0009] The gas distribution module is used to input standard reactant gases of different components and sample gases;

[0010] The input end of the multi-mode combined switching valve is connected to the zero air generation module and the air distribution module;

[0011] The first output end of the multi-mode combined switching valve is connected to the air inlet of the free radical generating source, the second output end is connected to the air inlet of the chemical amplification chamber, and the third output end is connected to the exhaust port of the chemical amplification chamber;

[0012] The exhaust port of the free radical generating source is connected to the air inlet of the chemical amplification chamber; the exhaust port of the chemical amplification chamber is also connected to the detection module;

[0013] The detection module includes a nitrogen dioxide analysis module and a broadband cavity enhanced nitrogen oxide analysis module.

[0014] Preferably, the zero gas generating device comprises:

[0015] Air compressor, zero air generator and mass flow meter;

[0016] The air compressor is used to input dry ambient air into the zero air generator;

[0017] The zero gas generator is used to remove SO from the input gas 2 , O 3 ,NO,NO 2 , CO components, obtain zero gas, and then output the zero gas to the mass flow meter;

[0018] The mass flow meter is used to control the input time and input flow rate of the zero gas.

[0019] Preferably, the gas distribution module is used to input CO, NO, N into the multi-mode combination switching valve. 2 and one or more of the sample gases.

[0020] Preferably, the chemical amplification chamber uses a Nafion tube and is equipped with a built-in temperature and humidity sensor.

[0021] Another object of an embodiment of the present application is to provide an ozone generation rate monitoring method, the method being implemented based on an ozone generation rate monitoring system as described above, the method comprising:

[0022] Perform chemical chain length calibration to obtain the chemical reaction chain length CL;

[0023] Obtain NO generated by chemical amplification of peroxyl radicals in the sample gas 2 Concentration value, based on NO 2The concentration value and the chemical reaction chain length CL value are used to obtain the total atmospheric peroxyl radicals [RO 2 *]concentration;

[0024] Obtain the nitric oxide concentration value of the sample gas sample, based on the nitric oxide concentration value and the total peroxyl free radicals [RO 2 *] concentration value to obtain the ozone photochemical production rate.

[0025] Preferably, the method for performing chemical chain length calibration to obtain the chemical reaction chain length CL is:

[0026] Based on the free radical source 2 O photolysis reaction to generate HO 2 and transport it to the chemical amplification chamber;

[0027] Based on the chemical amplification chamber, the input HO 2 It undergoes a chain reaction with the input NO and CO, converting into stable NO 2 ;

[0028] Detection of nitrogen dioxide concentration difference based on the broadband cavity enhanced nitrogen dioxide analysis module ,based on The value of the chemical reaction chain length CL is obtained.

[0029] Preferably, the NO generated by chemical amplification of peroxyl radicals in the sample gas sample is obtained. 2 concentration values, and based on NO 2 The concentration value and the chemical reaction chain length CL value are used to obtain the total atmospheric peroxyl radicals [RO 2 *] The concentration method is:

[0030] The sample gas sample, CO, NO and N 2 Injecting into the chemical amplification chamber;

[0031] Based on the chemical amplification chamber, the peroxyl radicals in the sample gas are , HO 2 Chain reaction with the reaction gas to generate stable NO 2 ;

[0032] Based on broadband cavity enhanced nitrogen dioxide analysis module, detect nitrogen dioxide concentration difference ,based on The value of total atmospheric peroxyl radicals [RO 2 *]concentration.

[0033] Preferably, the nitric oxide concentration value of the sample gas sample is obtained, and based on the nitric oxide concentration value and the total peroxyl radicals [RO 2*] concentration value, the method to obtain the ozone photochemical generation rate is:

[0034] The ozone photochemical production rate P was calculated based on the following formula:

[0035]

[0036] in, For NO and RO 2 *Reaction rate constant, It is the concentration of nitric oxide monitored by the broadband cavity enhanced nitrogen oxide analysis module during the nitrogen oxide concentration detection process of the sample gas. [RO 2 *]and These are the atmospheric peroxyl free radical concentrations obtained during the detection of the peroxyl free radical concentration in the sample gas.

[0037] Preferably, the method further comprises obtaining the contribution of nitrogen oxides to ozone generation;

[0038] The method to obtain the generated contribution is:

[0039] The controller adjusts the sample gas introduction rate to obtain different reactant concentrations;

[0040] Record the ozone photochemical production rate at different reactant concentrations to obtain P-NOx-NO / NO 2 The correspondence of data;

[0041] Based on the corresponding relationship, P-NOx-NO / NO is obtained. 2 Scatter plots of data;

[0042] Based on the scatter plot, NOx and NO / NO 2 Effect on ozone generation rate.

[0043] The ozone generation rate monitoring system provided in the embodiment of the present application has the outstanding advantage of accurately measuring the total peroxyl radicals (RO 2 *) concentration, nitric oxide (NO) concentration, and combined with the reaction rate constant, the ozone photochemical generation rate can be directly obtained, avoiding errors in model simulation results and filling the gap in the equipment market. The test results can provide more direct and effective data support for atmospheric ozone pollution control. By using the chemical amplification method to detect total peroxyl radicals, peroxyl radicals with low concentration, high activity and short existence time are converted into more stable and easy-to-measure nitrogen dioxide. Compared with traditional model simulation methods, it has the advantages of high accuracy and fast acquisition speed. By using broadband cavity enhanced absorption spectroscopy (BBCEAS) for nitrogen oxides (NOx) detection, nitrogen dioxide (NO 2) is a direct measurement, which can effectively avoid the influence of conversion efficiency and other interfering substances, and has the advantages of low detection limit, high accuracy and fast response speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 A structural module diagram of an ozone generation rate monitoring system provided in an embodiment of the present application;

[0045] Figure 2 A flow chart of a method for monitoring ozone generation rate provided in an embodiment of the present application;

[0046] Figure 3 A schematic diagram of the analysis results of the effect of nitrogen oxides on the photochemical generation rate of ozone provided in an embodiment of the present application. DETAILED DESCRIPTION

[0047] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0048] It is understood that the terms "first", "second", etc. used in this application may be used herein to describe various elements, but unless otherwise specified, these elements are not limited by these terms. These terms are only used to distinguish a first unit or module from another unit or module. For example, a first script may be referred to as a second script, and similarly, a second script may be referred to as a first script without departing from the scope of this application.

[0049] In one embodiment, Figure 1 As shown, it is a structural module diagram of an ozone generation rate monitoring system provided in an embodiment of the present application.

[0050] In this embodiment, the ozone generation rate monitoring system at least includes: a zero gas generation module, a gas distribution module, a multi-mode combination switching valve, a free radical generation source, a chemical amplification chamber and a detection module; the zero gas generation module is used to obtain zero gas and input it into the detection system; the gas distribution module is used to input standard reactant gases of different components and sample gas sample; the input end of the multi-mode combination switching valve is connected to the zero gas generation module and the gas distribution module; the first output end of the multi-mode combination switching valve is connected to the air inlet of the free radical generation source, the second output end is connected to the air inlet of the chemical amplification chamber, and the third output end is connected to the exhaust port of the chemical amplification chamber; the exhaust port of the free radical generation source is connected to the air inlet of the chemical amplification chamber; the exhaust port of the chemical amplification chamber is also connected to the detection module; the detection module includes a nitrogen dioxide analysis module and a broadband cavity enhanced nitrogen oxide analysis module.

[0051] In the embodiment of the present application, the gas distribution module can be used to collect and / or input the gas to be tested, i.e., the sample gas, as well as CO, NO, N 2 Standard gas is introduced into the system to ensure the representativeness of the sampled gas, which may contain units such as particulate matter filters. The gas distribution module is used to input gases of specific components into the system. The multi-mode combination switching valve contains multiple input and output ports, which can control the opening and closing of each input and output port. The free radical generator can perform H 2 O photolysis reaction to generate HO 2 The chemical amplification chamber can provide a controllable reaction environment and assist the internal reaction through chain reaction, temperature, humidity and pressure control. The broadband cavity enhanced nitrogen oxide (NOx) analysis module can simultaneously detect NO and The nitrogen dioxide analysis module can directly measure concentration.

[0052] In this embodiment, the multi-mode combined switching valve has the ability to control the gas output path and flow rate, which is connected to the free radical generator and the chemical amplification chamber inlet in sequence, and can input a quantitative amount of N 2 Gas, and can also input a certain amount of NO, N 2 The multi-mode combined switching valve is also connected to the exhaust port of the chemical amplification chamber, and can input a quantitative amount of CO gas into the exhaust port of the chemical amplification chamber to completely convert the remaining peroxyl radicals. In the detection module, the nitrogen dioxide analysis module adopts BBCEAS Analysis module, can directly analyze Concentration, broadband cavity enhanced nitrogen oxide analysis module can adopt BBCEAS NOx detection module, which can be connected and detected independently.

[0053] Compared with the prior art, this application has many outstanding advantages in the following aspects:

[0054] (1) This application accurately measures the total peroxyl radicals (RO 2 *) concentration, nitric oxide (NO) concentration, and combined with the reaction rate constant, the ozone photochemical generation rate can be directly obtained, avoiding errors in model simulation results and filling the gap in the equipment market. The test results can provide more direct and effective data support for atmospheric ozone pollution control.

[0055] (2) This application adopts the chemical amplification method to detect total peroxyl radicals, converting peroxyl radicals with low concentration, high activity and short existence time into more stable and easy to measure nitrogen dioxide. Compared with the traditional model simulation method, it has the advantages of high accuracy and fast acquisition speed.

[0056] (3) This application uses broadband cavity enhanced absorption spectroscopy (BBCEAS) to detect nitrogen oxides (NOx), in which nitrogen dioxide (NO 2 ) is a direct measurement, which can effectively avoid the influence of conversion efficiency and other interfering substances, and has the advantages of low detection limit, high accuracy and fast response speed.

[0057] (4) This application adopts an automated control scheme for different detection processes, which can realize online monitoring of the generation rates of total peroxyl radicals, nitrogen oxides and ozone in the atmosphere, and at the same time evaluate the impact of nitrogen oxides on the photochemical generation rate of atmospheric ozone, thus solving the technical problems of ozone pollution cause analysis and pollution control decision-making.

[0058] In a preferred embodiment, the zero gas generating device comprises:

[0059] An air compressor, a zero gas generator and a mass flow meter; the air compressor is used to input dry ambient air into the zero gas generator; the zero gas generator is used to remove SO in the input gas 2 , O 3 ,NO,NO 2 , CO components to obtain zero gas, and then output the zero gas to the mass flow meter; the mass flow meter is used to control the input time and input flow of the zero gas.

[0060] In the embodiment of the present application, the zero gas generation module is formed by combining the above devices, and may also include more or fewer modules or units.

[0061] In a preferred embodiment, the gas distribution module is used to input CO, NO, N 2 And one or more of the sample gases sample.

[0062] In a preferred embodiment, the chemical amplification chamber uses a Nafion tube with a built-in temperature and humidity sensor. The sample gas can be obtained directly from the environment, or the gas in the environment can be stored and then obtained. The system can control the gas composition, time, flow rate, etc. input to the reaction system by controlling the gas distribution module or the multi-mode combination switching valve.

[0063] Since the ozone generation reaction is sensitive to humidity, too high or too low humidity will affect the reaction rate and product distribution. Therefore, in the embodiment of the present application, the chemical amplification chamber adopts Nafion tube, which is corrosion-resistant and high-temperature-resistant and suitable for strong oxidizing environments, such as ozone generation reactions. The humidity in the chemical amplification chamber can be accurately adjusted by controlling the humidity difference inside and outside the Nafion tube. The sensor monitors the temperature and humidity in the chamber in real time to ensure that it is in the optimal reaction range for easy adjustment.

[0064] like Figure 2As shown, in a preferred embodiment, a method for monitoring ozone generation rate is also provided. The method can be implemented based on an ozone generation rate monitoring system as described above, and the method comprises:

[0065] S10, performing chemical chain length calibration to obtain a chemical reaction chain length CL;

[0066] S20, obtain NO generated by chemical amplification of peroxyl radicals in sample gas 2 concentration values, and based on NO 2 The concentration value and the chemical reaction chain length CL value are used to obtain the total atmospheric peroxyl radicals [RO 2 *]concentration;

[0067] S30, obtaining the nitric oxide concentration value of the sample gas sample, and based on the nitric oxide concentration value and the total peroxyl free radicals [RO 2 *] concentration value to obtain the ozone photochemical production rate.

[0068] In the present embodiment, the chemical chain length (CL) is first determined, that is, the number of ozone molecules generated in the chain reaction initiated by each initial free radical. The CL value is calculated by measuring the change in nitrogen dioxide concentration before and after the reaction. Then the total peroxyl radicals in the sample gas are measured. The concentration of It is a key intermediate in ozone generation, and its concentration directly reflects the potential for ozone generation. concentration and NO concentration to calculate the photochemical generation rate of ozone .

[0069] This solution can be used to measure and monitor the ozone generation rate through chemical amplification chamber and free radical detection technology. The chemical chain length can be calibrated according to the actual environmental conditions and is suitable for monitoring needs in different regions and seasons. Combined with the multi-mode switching valve and rapid detection module, real-time monitoring of the ozone generation rate can be achieved.

[0070] In a preferred embodiment, the method for performing chemical chain length calibration to obtain the chemical reaction chain length CL is:

[0071] Based on the free radical source 2 O photolysis reaction to generate HO 2 The free radicals are transported to the chemical amplification chamber; based on the chemical amplification chamber, the input HO 2 It undergoes a chain reaction with the input NO and CO, converting into stable NO 2 ; Detecting nitrogen dioxide concentration difference based on the broadband cavity enhanced nitrogen dioxide analysis module ,based on The value of the chemical reaction chain length CL is obtained.

[0072] In the embodiment of the present application, a broadband cavity enhanced nitrogen dioxide analysis module can be used to detect the difference in nitrogen dioxide concentration before and after the reaction. . [HO 2 ] indicates that H 2 0 HO generated by photolysis 2 concentration.

[0073] In a preferred embodiment, the NO generated by chemical amplification of peroxyl radicals in the sample gas sample is obtained. 2 concentration values, and based on NO 2 The concentration value and the chemical reaction chain length CL value are used to obtain the total atmospheric peroxyl radicals [RO 2 *] The concentration method is:

[0074] The sample gas sample, CO, NO and N 2 Injecting into the chemical amplification chamber;

[0075] Based on the chemical amplification chamber, the peroxyl radicals in the sample gas are , HO 2 Chain reaction with the reaction gas to generate stable NO 2 ;

[0076] Based on broadband cavity enhanced nitrogen dioxide analysis module, detect nitrogen dioxide concentration difference ,based on The value of total atmospheric peroxyl radicals [RO 2 *]concentration.

[0077] In the embodiment of the present application, the ambient sample gas is first introduced into the reaction system, and the sample gas may contain active substances such as peroxyl radicals, and then the reaction gas (CO, NO) and the dilution gas are provided. , used to trigger the chain reaction and control the reaction conditions. After the chain reaction, measure the reaction before and after The concentration changes, and then the free radicals [RO 2 *]concentration.

[0078] In a preferred embodiment, the nitric oxide concentration value of the sample gas sample is obtained, and based on the nitric oxide concentration value and the total peroxyl radicals [RO 2 *] concentration value, the method to obtain the ozone photochemical generation rate is:

[0079] The ozone photochemical production rate P was calculated based on the following formula:

[0080]

[0081] in, For NO and RO 2 *Reaction rate constant, It is the concentration of nitric oxide monitored by the broadband cavity enhanced nitrogen oxide analysis module during the nitrogen oxide concentration detection process of the sample gas. [RO 2 *]and These are the atmospheric peroxyl free radical concentrations obtained during the detection of the peroxyl free radical concentration in the sample gas.

[0082] In the embodiment of the present application, the ozone photochemical generation rate P can be obtained more accurately and directly based on the above method.

[0083] Compared with the existing technology, this method has many outstanding advantages in the following aspects: (1) This application accurately determines the total peroxyl radicals (RO 2 *) concentration, nitric oxide (NO) concentration, and combined with the reaction rate constant, the ozone photochemical generation rate is directly obtained, avoiding errors in model simulation results and filling the gap in the equipment market. The detection results can provide more direct and effective data support for atmospheric ozone pollution control. (2) This application uses chemical amplification to detect total peroxyl radicals, converting peroxyl radicals with low concentration, high activity and short existence time into more stable and easy-to-measure nitrogen dioxide. Compared with traditional model simulation methods, it has the advantages of high accuracy and fast acquisition speed. (3) This application uses broadband cavity enhanced absorption spectroscopy (BBCEAS) to detect nitrogen oxides (NOx), in which nitrogen dioxide (NO 2 ) is a direct measurement, which can effectively avoid the influence of conversion efficiency and other interfering substances, and has the advantages of low detection limit, high precision and fast response speed. (4) This application adopts an automated control scheme for different detection processes, which can realize the online monitoring of the total peroxyl radicals, nitrogen oxides and ozone generation rate in the atmosphere, and can also evaluate the impact of nitrogen oxides on the photochemical generation rate of atmospheric ozone, solving the technical problems of ozone pollution cause analysis and pollution control decision-making.

[0084] In a preferred embodiment, the method further comprises obtaining the contribution of nitrogen oxides to ozone generation;

[0085] The method to obtain the generated contribution is:

[0086] The controller adjusts the sample gas introduction rate to obtain different reactant concentrations;

[0087] Record the ozone photochemical production rate at different reactant concentrations to obtain P-NOx-NO / NO 2 The correspondence of data;

[0088] Based on the corresponding relationship, P-NOx-NO / NO is obtained. 2 Scatter plots of data;

[0089] Based on the scatter plot, NOx and NO / NO 2 Effect on ozone generation rate.

[0090] In this embodiment, P is P(O 3 ), represents the photochemical generation rate of ozone, NOx is the ozone precursor nitrogen oxides, NO / NO 2 is the ratio of nitric oxide concentration to nitrogen dioxide concentration. First, adjust the sample gas introduction rate through the mass flow controller (for example, the flow rate increases from 0L / min to 0.5L / min, and increases by 0.1L / min every ten minutes), obtain reactants of different concentrations, and observe and record the ozone photochemical generation rate. And P(O 3 )-NOx-NO / NO 2 The data is plotted as Figure 3 The scatter plot shown above determines the NOx and NO / NO 2 Effect on ozone generation rate.

[0091] In this embodiment, based on Figure 3 The scatter plot shown in the figure shows that if the NOx concentration is constant, P(O 3 )With NO / NO 2 The ratio increases with the increase, which means that P(O 3 ) and NO / NO 2 The ratios are positively correlated.

[0092] in NO / NO 2 When the ratio is low, P(O 3 ) is less affected by NOx concentration.

[0093] in NO / NO 2 When the ratio is high, P(O 3 ) increases with the increase of NOx concentration.

[0094] P(O 3 ) and NOx concentration in NO / NO 2 When the ratio is high, it is positively correlated. 2 When the ratio is low, there is no relationship or little relationship.

[0095] Based on the above results, it can be judged that NOx and NO / NO 2 Contribution to ozone generation rate.

[0096] Those skilled in the art will understand that Figure 1 and Figure 2The structure or step block diagram shown is only a block diagram of a partial structure related to the present application scheme, and does not constitute a limitation on the system or method to which the present application scheme is applied. The specific system or method may include more or fewer components or steps than those shown in the figure, or combine certain components or steps.

[0097] It should be understood that, although each step in the flow chart of each embodiment of the present application is shown in sequence according to the indication of the arrow, these steps are not necessarily performed in sequence according to the order indicated by the arrow. Unless there is clear explanation in this article, the execution of these steps does not have strict order restriction, and these steps can be performed in other orders. Moreover, at least a portion of the steps in each embodiment may include a plurality of sub-steps or a plurality of stages, and these sub-steps or stages are not necessarily performed at the same time, but can be performed at different times, and the execution order of these sub-steps or stages is not necessarily performed in sequence, but can be performed in turn or alternately with at least a portion of other steps or sub-steps or stages of other steps.

[0098] A person of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing related hardware through a computer program. The program can be stored in a non-volatile computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods.

[0099] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0100] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. An ozone generation rate monitoring system, characterized in that: The system comprises: Zero gas generation module, gas distribution module, multi-mode combination switching valve, free radical generation source, chemical amplification chamber and detection module; The zero gas generation module is used to obtain zero gas and input it into the system; The gas distribution module is used to input standard reactant gases of different components and sample gases; The input end of the multi-mode combined switching valve is connected to the zero air generation module and the air distribution module; The first output end of the multi-mode combined switching valve is connected to the air inlet of the free radical generating source, the second output end is connected to the air inlet of the chemical amplification chamber, and the third output end is connected to the exhaust port of the chemical amplification chamber; The exhaust port of the free radical generating source is connected to the air inlet of the chemical amplification chamber; the exhaust port of the chemical amplification chamber is also connected to the detection module; The detection module includes a nitrogen dioxide analysis module and a broadband cavity enhanced nitrogen oxide analysis module.

2. An ozone generation rate monitoring system according to claim 1, characterized in that: The zero gas generating device comprises: Air compressor, zero air generator and mass flow meter; The air compressor is used to input dry ambient air into the zero air generator; The zero gas generator is used to remove SO2, O3, NO, NO2, and CO components in the input gas to obtain zero gas, and then output the zero gas to the mass flow meter; The mass flow meter is used to control the input time and input flow rate of the zero gas.

3. An ozone generation rate monitoring system according to claim 1, characterized in that: The gas distribution module is used to input one or more of CO, NO, N2 and sample gas sample into the multi-mode combination switching valve.

4. An ozone generation rate monitoring system according to claim 1, characterized in that: The chemical amplification chamber adopts a Nafion tube and is equipped with a temperature and humidity sensor.

5. A method for monitoring ozone generation rate, characterized in that: The method is implemented based on an ozone generation rate monitoring system according to any one of claims 1 to 5, and the method comprises: Perform chemical chain length calibration to obtain the chemical reaction chain length CL; Obtain the NO2 concentration value generated by chemical amplification of peroxyl radicals in the sample gas sample, and obtain the total atmospheric peroxyl radical [RO2*] concentration based on the NO2 concentration value and the value of the chemical reaction chain length CL; The nitric oxide concentration value of the sample gas sample is obtained, and based on the nitric oxide concentration value and the total atmospheric peroxyl radical [RO2*] concentration value, the ozone photochemical generation rate is obtained.

6. The method for monitoring ozone generation rate according to claim 5, characterized in that: The method for chemical chain length calibration to obtain the chemical reaction chain length CL is: Based on the free radical source, the photolysis reaction of H2O is carried out to generate HO2 and transport it to the chemical amplification chamber; Based on the chemical amplification chamber, the input HO2 undergoes a chain reaction with the input NO and CO, and is converted into stable NO2; Detection of nitrogen dioxide concentration difference based on the broadband cavity enhanced nitrogen dioxide analysis module ,based on The value of the chemical reaction chain length CL is obtained.

7. The method for monitoring ozone generation rate according to claim 5, characterized in that: The method for obtaining the NO2 concentration value generated by the chemical amplification of the peroxyl free radicals in the sample gas sample and obtaining the total atmospheric peroxyl free radical [RO2*] concentration based on the NO2 concentration value and the value of the chemical reaction chain length CL is as follows: Inject sample gas, CO, NO and N2 into the chemical amplification chamber; Based on the chemical amplification chamber, the peroxyl radicals in the sample gas are , HO2 undergoes a chain reaction with the reaction gas to generate stable NO2; Based on broadband cavity enhanced nitrogen dioxide analysis module, detect nitrogen dioxide concentration difference ,based on The value of is used to obtain the total atmospheric peroxyl radical [RO2*] concentration.

8. The method for monitoring ozone generation rate according to claim 5, characterized in that: The method for obtaining the nitric oxide concentration value of the sample gas sample and obtaining the ozone photochemical generation rate based on the nitric oxide concentration value and the total atmospheric peroxyl radical [RO2*] concentration value is as follows: The ozone photochemical production rate P was calculated based on the following formula: in, is the reaction rate constant of NO and RO2*, The concentration of nitric oxide monitored by the broadband cavity enhanced nitrogen oxide analysis module during the nitrogen oxide concentration detection process of the sample gas, [RO2*] and These are the atmospheric peroxyl free radical concentrations obtained during the detection of peroxyl free radical concentrations in sample gas.

9. The method for monitoring ozone generation rate according to claim 5, characterized in that: The method also includes obtaining the contribution of nitrogen oxides to ozone generation; The method to obtain the generated contribution is: The controller adjusts the sample gas introduction rate to obtain different reactant concentrations; Record the ozone photochemical generation rate under different reactant concentrations and obtain the corresponding relationship of P-NOx-NO / NO2 data; Based on the corresponding relationship, a scatter plot of P-NOx-NO / NO2 data is obtained; Based on the scatter plot, the effects of NOx and NO / NO2 on the ozone generation rate are obtained.

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