System and method for judging atmospheric combined pollution process

Abstract

The embodiment of the invention discloses a system and a method for judging an atmospheric combined pollution process. The judgment system comprises an O3 standard exceeding day determination unit; an O3 pollution process determination unit; a PM2.5 standard exceeding day determination unit; a PM2.5 pollution process determination unit; a unit for determining the light and more pollutants; and a determination unit. Under the background of continuous improvement of the atmospheric environment, the combined pollution process can be extracted more finely, judgment of the combined pollution events is more comprehensively concluded, the screening effect of the combined pollution events is improved, and the pollution degree can be calculated.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of environmental monitoring, and in particular to a system and method for determining a complex atmospheric pollution process. Background Art

[0002] In 2021, Dr. Zhang Zirui conducted a study on PM2.5 in Beijing. 2.5 The following method was used to analyze the dual pollution process of PM (particulate matter with a diameter less than 2.5 μm) and O3 (tropospheric ozone): According to the secondary standard limit of atmospheric pollutants in the Ambient Air Quality Standard (GB3095-2012), PM 2.5 The daily average concentration exceeds 75 μg / m 3 The pollution day is defined as PM 2.5 On days when the limit is exceeded, PM will appear for 2 consecutive days or more. 2.5 The process of exceeding the standard is defined as PM 2.5 Pollution process. The maximum sliding average value of O3 exceeds 160μg / m 3 Polluted days are defined as days with excessive O3, and the process of two or more consecutive days with excessive O3 is defined as an O3 pollution process. 2.5 The process of exceeding the standard on the same day or on the same day as O3 and reaching at least a mild pollution level is defined as PM 2.5 And O3 double pollution process.

[0003] Against the backdrop of improving air quality year after year, re-examinations of pollution often show the characteristics of short duration pollution. The method proposed by Dr. Zhang Zirui uses daily evaluation concentration as the judgment standard, and identifies fewer complex pollution processes. It is very easy to ignore the characteristics of short-term complex pollution, which is not conducive to the current needs for refined management and control.

[0004] Atmospheric composite pollution refers to a complex atmospheric pollution system formed by the interaction and coupling of multiple interfaces between multiple pollutants from multiple sources under certain atmospheric conditions (such as temperature, humidity, sunlight, etc.). It is mainly a scenario of increased concentrations of atmospheric oxidizing species and fine particulate matter, usually manifested as O3 and PM 2.5 However, the concentration increase period of these two types of pollutants is different, and the peak concentration can increase synchronously, successively, staggered, etc. Therefore, it is necessary to provide a judgment method for the atmospheric complex pollution process to more clearly judge and analyze the pollution degree of the atmospheric complex pollution process, so as to clarify and coordinate the control of PM2.5 by relevant departments. 2.5 It provides a certain theoretical basis for O3 and further improves the air quality. Summary of the invention

[0005] To this end, the present invention has been modified and further improved on the basis of Dr. Zhang Zirui's research on dual pollution process analysis, mainly judging compound pollution events based on the accumulation, accumulation and diffusion process of ozone and particulate matter, exploring the relationship between O3 and PM 2.5 The composite pollution process determination method is to determine the impact of ozone pollution on the rapid generation of particulate matter during the development stage, and analyze the pollution degree of the composite pollution process. The system and method for determining the atmospheric composite pollution process provided by the present invention can more clearly determine and analyze the pollution degree of the atmospheric composite pollution process.

[0006] In order to achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0007] According to a first aspect of an embodiment of the present invention, the present invention provides a system for determining a complex atmospheric pollution process, the system comprising:

[0008] O3 exceeding standard day determination unit, determines O3 exceeding standard day according to the maximum sliding 8-hour average value of O3 day;

[0009] The O3 pollution process determination unit determines the O3 pollution process based on whether there are at least 2 consecutive days of O3 exceeding the standard;

[0010] PM 2.5 The unit for determining the days exceeding the standard is based on PM 2.5 PM 2.5 Polluted days;

[0011] PM 2.5 The pollution process determination unit is based on whether PM2.5 appears for at least 2 consecutive days. 2.5 PM 2.5 Pollution process;

[0012] The units where pollutants are lightly polluted or above are determined according to the air quality index IAQI;

[0013] Judgment unit, based on O3 exceeding standard day determination unit, O3 pollution process determination unit, PM 2.5 Exceeding the standard day determination unit, PM 2.5 The pollution process determination unit and the results of the pollutant occurrence light or above pollution determination units are used to determine whether it is an atmospheric complex pollution process.

[0014] Furthermore, the judging process of the judging unit is as follows:

[0015] O3 exceeding standard days determined by O3 exceeding standard day determination unit and PM 2.5 PM determined by the unit for exceeding the standard day 2.5If the days of exceeding the standard are on the same day or adjacent days, and there are at least two consecutive days of light pollution or above, it is regarded as a complex atmospheric pollution process;

[0016] O3 pollution process or PM 2.5 When a pollution process occurs and the hourly concentration of another pollutant reaches light pollution or above, it is regarded as an atmospheric complex pollution process.

[0017] Furthermore, the 8-hour average value of the maximum daily sliding O3 value exceeded 160 μg / m 3 Polluted days are determined as O3 exceeding standard days;

[0018] PM 2.5 The daily average concentration exceeds 75 μg / m 3 The pollution days are determined as PM 2.5 Exceeding the standard days;

[0019] When the air quality index IAQI is greater than 100, it is determined that the corresponding pollutants are mildly polluted or above.

[0020] Furthermore, the judgment system also includes a pollution degree calculation unit.

[0021] According to a second aspect of an embodiment of the present invention, the present invention provides a method for determining an atmospheric composite pollution process, the method comprising:

[0022] When O3 exceeds the standard and PM 2.5 If the days of exceeding the standard are on the same day or adjacent days, and there are at least two consecutive days of light pollution or above, it is regarded as a complex atmospheric pollution process;

[0023] In the case of O3 pollution or PM 2.5 When a pollution process occurs and the hourly concentration of another pollutant reaches light pollution or above, it is regarded as an atmospheric complex pollution process.

[0024] Furthermore, the 8-hour average value of the maximum daily sliding O3 value exceeded 160 μg / m 3 Polluted days are defined as days with excessive O3 and PM 2.5 The daily average concentration exceeds 75 μg / m 3 The pollution day is defined as PM 2.5 Polluted days;

[0025] The process of excessive O3 for at least 2 consecutive days is defined as an O3 pollution process. 2.5 The process of exceeding the standard is defined as PM 2.5 Pollution process;

[0026] When the air quality index IAQI is greater than 100, it is considered that the corresponding pollutants are mildly polluted or above.

[0027] Furthermore, the method also includes: calculating the pollution degree of the identified complex pollution process.

[0028] The embodiments of the present invention have the following advantages:

[0029] The judgment of the atmospheric composite pollution process provided by the present invention is divided into two types, and the situation in which continuous multi-pollutant pollution days and another pollutant exceeds the standard for one hour in a single pollution process are both regarded as composite pollution processes. In the context of continuous improvement of the atmospheric environment, this method can extract composite pollution processes more finely and make a more comprehensive summary of the judgment of composite pollution events. By improving and optimizing the judgment method of composite pollution processes, it not only increases the screening effect of composite pollution events, but also can calculate the degree of pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0031] Figure 1 A schematic diagram of the structure of the judgment system for the atmospheric composite pollution process provided by the present invention;

[0032] Figure 2 The hourly and daily evaluation concentration exceeding the standard of O3 concentration in process A provided by the present invention;

[0033] Figure 3 PM in process A provided by the present invention 2.5 Hourly and daily evaluation of concentration and concentration exceeding the standard. DETAILED DESCRIPTION

[0034] The following is a description of the implementation of the present invention by specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] PM 2.5 The pollution level of O3 and PM2.5 is determined by referring to the Technical Regulations on Ambient Air Quality Index (AQI) (Trial) (HJ633-2012). 2.5 The air quality index IAQI determination method is that when the IAQI is greater than 100, it is considered that the corresponding pollutants are slightly polluted or above.

[0036] O3 and PM 2.5 The analytical method of concentration is shown in Table 1 below.

[0037] Table 1 Pollutant analysis methods

[0038]

[0039] Example 1

[0040] See also Figure 1 This embodiment provides a system for determining an atmospheric composite pollution process. The system includes: an O3 exceeding standard day determination unit, an O3 pollution process determination unit, a PM 2.5 Exceeding the standard day determination unit, PM 2.5 Pollution process determination unit, pollutant occurrence light pollution and above determination unit, judgment unit, pollution degree calculation unit. Among them:

[0041] O3 exceeding standard day determination unit: used to determine whether a pollution day is an O3 exceeding standard day. When the maximum sliding 8-hour average value of O3 exceeds 160μg / m 3 Polluted days (secondary limit) are defined as days when O3 exceeds the standard.

[0042] The maximum sliding 8-hour average of O3 refers to the maximum value of all 8-hour sliding average concentrations from 8:00 to 24:00 in a natural day, μg / m 3 , and its calculation formula is as follows:

[0043]

[0044] Among them, C t It is the average pollutant concentration of ozone from t-1 to t on a certain day.

[0045] O3 pollution process determination unit: used to determine whether the process with O3 exceeding the standard is an O3 pollution process. A process with O3 exceeding the standard for 2 or more consecutive days is defined as an O3 pollution process.

[0046] PM 2.5 Exceeding standard day determination unit: used to determine whether the pollution day is PM 2.5 Exceeding the limit day. 2.5 The daily average concentration exceeds 75 μg / m 3 (Level 2 limit) pollution days are defined as days when PM2.5 exceeds the standard. The calculation formula for the average daily concentration of PM2.5 is:

[0047] N=(PM 2.5 Concentration value 1+PM 2.5 Concentration value 2+...+ozone concentration value 24) / 24

[0048] Where N is PM 2.5 Average daily concentration; PM 2.5 Concentration value 1, PM 2.5 Concentration value 2, ..., PM 2.5 The concentration value 24 represents the PM concentration for each hour between 1:00 and 24:00. 2.5 concentration.

[0049] PM 2.5 Pollution process determination unit: used to determine PM 2.5 Is the process of exceeding the standard day PM 2.5 Pollution process. PM2.5 will appear for 2 consecutive days or more 2.5 The process of exceeding the standard is defined as the O3 pollution process.

[0050] Unit for determining light or above pollution of pollutants: Determine light or above pollution of pollutants and light or above pollution of hourly concentrations based on the air quality index IAQI.

[0051] For the calculation method of the air quality index IAQI, please refer to the "Technical Regulations on Ambient Air Quality Index (AQI)" HJ 633-2012.

[0052] Judgment unit: In order to more accurately identify compound pollution, the following two situations are defined as compound pollution processes:

[0053] 1. O3 exceeding standard days determined by O3 exceeding standard day determination unit and PM 2.5 PM determined by the unit for exceeding the standard day 2.5 Exceeding-standard days are days when pollution levels are mild or above for at least two consecutive days on the same or adjacent days. Specifically, they can be divided into the following four situations: 1. The first day is an O3 exceeding-standard day, and at least the next day is a PM 2.5 Exceeding the standard day; 2. The first day is PM 2.5 If the day is exceeded, at least the next day will be an O3 exceeded day; 3. If the first day is also PM 2.5 On days when the limit is exceeded and O3 exceeds the limit, at least the next day is PM 2.5 Exceeding the standard day; 4. PM on the first day 2.5 For days with excessive pollution and days with excessive O3, at least the next day will be an excessive O3 day. Among them, mild pollution or above means that the maximum sliding 8-hour average value of O3 exceeds 160μg / m 3 , or, PM 2.5 The daily average concentration exceeds 75 μg / m 3 .

[0054] 2. In the case of O3 pollution or PM 2.5 During the pollution process, another pollutant appears in hourly concentrations reaching mild pollution or above.

[0055] Pollution degree calculation unit: used to calculate the pollution degree of the identified complex pollution process. The comprehensive air quality index used in the Technical Regulations on Urban Ambient Air Quality Ranking is introduced to define the pollution degree. 2.5 The concentration of PM2.5 and O3 is dimensionless to obtain the single mass index of each pollutant, and then the single mass index is added to obtain the composite pollution comprehensive index Ic (Formula 1) of a composite pollution process, which is used to define the pollution degree of a composite pollution process. The larger the composite pollution comprehensive index, the higher the concentration of PM2.5 and O3. 2.5 The degree of compound pollution is more serious.

[0056]

[0057] Where:

[0058] C PM2.5 ——PM 2.5 Daily average concentration, μg / m 3 ;

[0059] S PM2.5 ——PM 2.5 The secondary concentration limit is 35 μg / m 3 .

[0060] C O3 ——O3 daily maximum sliding 8-hour average value;

[0061] S O3 ——The secondary concentration limit of O3 is 160μg / m 3 .

[0062] Example 2

[0063] This embodiment provides a method for determining an atmospheric composite pollution process based on the system of embodiment 1, and the method comprises the following steps:

[0064] (1) Monitor the ozone concentration every hour between 8:00 and 24:00 every day and calculate the maximum sliding 8-hour average value of O3. When the maximum sliding 8-hour average value of O3 exceeds 160 μg / m 3 When the day is over, it is determined that the day is an O3 excess day;

[0065] Monitor PM every hour between 1:00 and 24:00 daily 2.5 concentration and calculate PM 2.5 Daily average concentration. 2.5 The daily average concentration exceeds 75 μg / m 3 , determine that the day is PM 2.5 Exceeding the standard day.

[0066] When O3 exceeds the standard and PM 2.5If the air pollution exceeds the standard on the same day or on adjacent days and there is light pollution or above for at least two consecutive days, it is regarded as a complex atmospheric pollution process.

[0067] (2) A process in which O3 exceeds the standard for at least 2 consecutive days is defined as an O3 pollution process;

[0068] PM appears for at least 2 consecutive days 2.5 The process of exceeding the standard day is defined as PM 2.5 Pollution process;

[0069] When O3 pollution occurs, PM 2.5 When the hourly concentration reaches mild pollution or above, it is regarded as a complex atmospheric pollution process;

[0070] In the presence of PM 2.5 During the pollution process, if the hourly concentration of O3 reaches mild pollution or above, it is regarded as a complex atmospheric pollution process.

[0071] (3) Calculate the pollution degree of the identified complex pollution process. Introduce the comprehensive air quality index used in the "Technical Regulations on Urban Ambient Air Quality Ranking" to define the pollution degree.

[0072] Example 3

[0073] Applying this method of judging the atmospheric complex pollution process, we classified the pollution process in Chengdu from 2019 to 2021, focused the complex pollution on the hourly basis, explored the time periods and characteristics of complex pollution, preliminarily analyzed the causes of the characteristics, and used the comprehensive index to judge the degree of pollution, providing a basic basis for subsequent research on the cause mechanism of complex pollution and identification of control targets.

[0074] Taking the two pollution processes from April 28 to May 6, 2020 (process A) and May 13 to May 16, 2020 (process B) as examples, if the double pollution process determination method is adopted, there will be PM 2.5 The process of exceeding the standard for two consecutive days with O3 and reaching a level above mild pollution is defined as a double pollution process. Then process A and process B are both single O3 pollutant pollution processes. However, in actual research, PM 2.5 The hourly concentration increases significantly, followed by a rapid decrease during the day, as shown by PM 2.5 The daily average concentration of PM 2.5 The pollution judgment criteria will ignore the characteristics of complex pollution, and in recent years PM 2.5 The concentrations all showed a downward trend, and the characteristics of complex pollution could not be fully defined using only the double pollution process determination method.

[0075] First, the daily O3 concentration and PM2.5 concentration observed by the automatic analysis method in Table 1 of this paper were 2.5The hourly concentration results comprehensively judge the two complex pollution processes that occurred in 2020. The following figure shows the analysis results of process A: From the O3 concentration chart, it can be seen that no matter from the hourly concentration or daily evaluation concentration time scale analysis, there are continuous exceeding of the standard (more than 160μg / m 3 limit), but during the same period PM 2.5 The daily concentration did not exceed the standard, but the hourly concentration exceeded the standard for many times (more than 75 μg / m 3 According to the data of recent years, with the continuous advancement of air pollution control, the double pollution process has continued to decrease or even stopped appearing, but individual hourly exceeding the limit is still common. In order to meet the requirements of refined control and continue to promote the improvement of the atmospheric environment, it is necessary to strengthen the analysis and research on hourly exceeding the limit.

[0076] Secondly, a comprehensive analysis of the two combined pollution processes showed that process A had 4 days of mild O3 pollution and 4 days of moderate O3 pollution, with a total of 24 hours of PM 2.5 Slight pollution, the composite pollution index Ic is 2.7; although the pollution duration of process B is shorter, it is 4 days of light O3 pollution, during which PM appears for 25 hours 2.5 The composite pollution index Ic is 3.0. In summary, although process A is polluted for a longer time than process B, the composite pollution level of process B is more serious.

[0077] Although the present invention has been described in detail above by general description and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements can be made to the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

Claims

1. A system for determining the atmospheric complex pollution process, characterized in that: The judgment system comprises: O3 exceeding standard day determination unit, determines O3 exceeding standard day according to the maximum sliding 8-hour average value of O3 day; The O3 pollution process determination unit determines the O3 pollution process based on whether there are at least 2 consecutive days of O3 exceeding the standard; PM 2.5 The unit for determining the days exceeding the standard is based on PM 2.5 PM 2.5 Polluted days; PM 2.5 The pollution process determination unit is based on whether PM2.5 appears for at least 2 consecutive days. 2.5 PM 2.5 Pollution process; The units where pollutants are lightly polluted or above are determined according to the air quality index IAQI; Judgment unit, based on O3 exceeding standard day determination unit, O3 pollution process determination unit, PM 2.5 Exceeding the standard day determination unit, PM 2.5 The pollution process determination unit and the results of the pollutant occurrence light or above pollution determination units are used to determine whether it is an atmospheric complex pollution process.

2. The system for determining the atmospheric complex pollution process according to claim 1, characterized in that: The judging process of the judging unit is as follows: O3 exceeding standard days determined by O3 exceeding standard day determination unit and PM 2.5 PM determined by the unit for exceeding the standard day 2.5 If the days of exceeding the standard are on the same day or adjacent days, and there are at least two consecutive days of light pollution or above, it is regarded as a complex atmospheric pollution process; O3 pollution process or PM 2.5 When a pollution process occurs and the hourly concentration of another pollutant reaches light pollution or above, it is regarded as an atmospheric complex pollution process.

3. The system for determining the atmospheric complex pollution process according to claim 1, characterized in that: The 8-hour average value of the maximum daily sliding O3 value exceeds 160 μg / m 3 Polluted days are determined as O3 exceeding standard days; PM 2.5 The daily average concentration exceeds 75 μg / m 3 The pollution days are determined as PM 2.5 Exceeding the standard days; When the air quality index IAQI is greater than 100, it is determined that the corresponding pollutants are mildly polluted or above.

4. The system for determining the atmospheric complex pollution process according to claim 1, characterized in that: The judgment system also includes a pollution degree calculation unit.

5. A method for determining a complex atmospheric pollution process, characterized in that: The determination method comprises: When O3 exceeds the standard and PM 2.5 If the days of exceeding the standard are on the same day or adjacent days, and there are at least two consecutive days of light pollution or above, it is regarded as a complex atmospheric pollution process; In the case of O3 pollution or PM 2.5 When a pollution process occurs and the hourly concentration of another pollutant reaches light pollution or above, it is regarded as an atmospheric complex pollution process.

6. The method for determining the atmospheric complex pollution process according to claim 5, characterized in that: The 8-hour average value of the maximum daily sliding O3 value exceeds 160 μg / m 3 Polluted days are defined as days with excessive O3 and PM 2.5 The daily average concentration exceeds 75 μg / m 3 The pollution day is defined as PM 2.5 Polluted days; The process of excessive O3 for at least 2 consecutive days is defined as an O3 pollution process. 2.5 The process of exceeding the standard is defined as PM 2.5 Pollution process; When the air quality index IAQI is greater than 100, it is considered that the corresponding pollutants are mildly polluted or above.

7. The method for determining the atmospheric complex pollution process according to claim 5, characterized in that: The method further comprises: calculating the pollution degree of the identified complex pollution process.

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