Planned burning-off technology for straw residues

Abstract

The invention relates to the field of straw burning, and discloses a planned burning technology for straw residues, in particular to a straw planned burning automatic program based on numerical simulation of a Air Quality Forecasting Mode System (WRF-CMAQ), and a method for controlling the straw residues in the straw burning automatic program based on the numerical simulation of the air Quality Forecasting Mode System (WRF-CMAQ) and the straw residues in the straw burning automatic program based on the air quality Forecasting Mode System (WRF-CMAQ). The program comprises a suitable condition screening module, an air quality pre-evaluation module, a process supervision module, a post-evaluation module and an automatic output analysis report module, the incineration suitability is automatically judged by combining meteorological data, air quality data and straw incineration list information, and the influence of burning-off on the air quality is evaluated by utilizing a numerical simulation technology, so that the air quality is automatically evaluated. The program realizes full-process automation of data acquisition, condition screening, model operation, process monitoring and result output, can quickly generate a prediction report, a pollution contribution analysis report and an actual execution effect evaluation report of a burning-off area, greatly improves scientificity and operability of a straw burning-off plan, effectively reduces the risk of environmental pollution, and improves the working efficiency of the straw burning-off plan. And technical support is provided for ecological environment management.

Description

Technical Field

[0001] The invention relates to the field of straw burning, in particular to a planned burning technology of straw residues. Background Art

[0002] In recent years, with the expansion of agricultural production, the annual output of crop straw has continued to increase. As a biomass resource, straw has multiple utilization values ​​such as feed, fertilizer and base material. However, in some areas, due to technical conditions or economic limitations, straw burning is still one of the main treatment methods. Although straw burning can quickly clean up field plots and make room for agricultural production, its disorderly and unscientific implementation will produce a large amount of pollutants, such as particulate matter (PM 2.5 、PM 10 ), ozone (O3) precursors (NOx and VOCs) and carbon monoxide (CO). These pollutants not only seriously affect the quality of the atmospheric environment, but may also aggravate pollution in downstream areas through regional transmission, threatening public health and ecological security.

[0003] In order to solve the problem of air pollution caused by straw burning, the national and local governments have issued a number of policies and regulations aimed at strictly restricting and scientifically managing straw burning activities. However, the existing management methods have many limitations: on the one hand, there is a lack of scientific and effective burning plan formulation tools, which cannot fully consider various complex factors such as meteorological conditions, air quality levels and pollutant transmission characteristics; on the other hand, the supervision measures are lagging behind, making it difficult to detect and stop illegal burning in a timely manner. In addition, the existing research on the assessment of straw burning pollution mostly remains at the static analysis stage, lacking dynamic adjustment mechanisms and automated analysis tools, which makes it difficult to meet the needs of precise management in practical applications.

[0004] The WRF-CMAQ numerical model provides new technical support for the scientific management of straw burning. WRF-CMAQ can simulate the spatiotemporal changes of pollutants in the atmosphere, providing an important basis for burning impact assessment and pollution source analysis. However, the current research on straw burning based on WRF-CMAQ mainly focuses on model application, lacks deep integration with automation programs, and cannot achieve full-process automation from data acquisition, plan formulation to result output. In response to these problems, the present invention proposes an automated straw burning program based on WRF-CMAQ numerical simulation, which aims to provide a new technical solution for straw burning management by scientifically screening suitable burning conditions, simulating and evaluating burning impacts, dynamically adjusting plans, and efficiently outputting evaluation results. Summary of the invention

[0005] The object of the present invention is to provide a planned burning technology for straw residues to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solution: a planned burning technology of straw residues, comprising the following steps:

[0007] Step 1: The provincial level issues a straw burning plan instruction. After receiving the instruction, each municipal ecological environment bureau determines the suitable conditions for straw burning. Specifically, it generates daily burning recommendations based on comprehensive factors such as air quality, wind speed, weather conditions and wind direction to ensure that straw burning meets environmental protection and safety requirements;

[0008] Step 2: Pre-assessment is to prepare for the disposal of straw residues after receiving the straw burning plan instruction from the Municipal Ecological Environment Bureau. In this stage, air quality control targets will be set and areas suitable for daily straw burning will be determined. Based on the generated simulation results, a spatial distribution map of the straw burning list will be drawn to show the geographical locations where the plan can be implemented, and a CSV file containing the burning information will be output to screen out the optimal burning plan.

[0009] Step 3: Process supervision is to use multi-source data analysis, stereoscopic observation and model analysis to conduct real-time supervision and planning of key areas during the burning process, respond to various emergencies through emergency response mechanisms, and issue dynamic control suggestions;

[0010] Step 4: Post-evaluation is a summary after the straw disposal is completed. In this stage, an evaluation model will be used to conduct a comprehensive evaluation of the effects of this round of work, and feedback will be provided to the Municipal Ecological Environment Bureau on the results, problems and improvement measures to further improve the straw management plan and planned burning system.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] The present invention is a temporary measure before the full-scale comprehensive utilization of straw, which helps to alleviate the agricultural production pressure in typical agricultural cities while reducing the degree of air pollution. Practice has proved that Suihua City has implemented straw disposal according to the straw burning technology described in the present invention, which has effectively reduced the degree of pollution when pollutant emissions have increased significantly and meteorological conditions have deteriorated overall. Specifically, PM2.5 in March and April 2024 was 1.347 million tons, an increase of 1.1% and 1.2% respectively. 2.5 The daily average concentration decreased by 4 μg / m compared with 2022 and 2023. 3 and 14.5 μg / m 3 .

[0013] The present invention can quickly output a straw burning plan assessment report and submit it to management personnel, which helps management departments to promptly discover deficiencies, clarify the causes of pollution incidents, and quickly improve disposal plans, providing technical support for avoiding pollution incidents. It has been verified in practice that in the moderate pollution incident in Suihua City from April 10 to April 11, 2024, the present invention quickly analyzed the causes of the pollution incident and found that the stealing and rushing burning behaviors in the suburbs of Beilin District, Suihua City after the boundary layer was lowered at night had a significant impact on PM2.5. 2.5 The concentration contribution rate reached more than 80%. The local government responded promptly and strengthened the supervision of nighttime burning in subsequent burnings, controlling the pollution caused by local illegal burning of straw at night. In addition, in a severe pollution incident from April 21 to April 22, 2024, this incident was mainly caused by the regional transmission of pollutants generated by large-scale burning of straw in Bayan County, Harbin, east of Beilin District, Suihua City, with a contribution rate of up to 70%. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is the overall technical roadmap of the present invention;

[0015] Figure 2 Provide a daily list of information on straw burning plans at the administrative village level;

[0016] Figure 3 Propose a technology roadmap for straw residue burning;

[0017] Figure 4 Develop a technical roadmap for WRF-CMAQ automation operations;

[0018] Figure 5 This is a schematic diagram of straw control during the spring straw burning plan in Suihua City;

[0019] Figure 6 A summary table of recommendations for straw residue disposal;

[0020] Figure 7 For the straw burning process supervision technology based on stereoscopic observation, (a) tower video fire point monitoring system, (b) satellite fire point observation technology, (c) ground-based laser radar observation technology, (d) UAV and drone observation technology;

[0021] Figure 8 Results of the cause analysis of moderate pollution events, (a) correlation analysis results, (b) nighttime incineration field observation verification, (c) wind speed and direction rose diagram analysis results, (d) PM 2.5 Potential source analysis results;

[0022] Fig. 9 The numerical simulation results of WRF-CMAQ are shown in Figure 2. (a) PM2.5 emissions from straw burning 2.5Spatial distribution of concentration, (b) PM without straw burning emissions 2.5 Spatial distribution of concentration (c) Emissions from straw burning on PM 2.5 Contribution rate of concentration (superimposed with ground wind field);

[0023] Fig.10 Report on the work of automated straw burning program;

[0024] Fig.11 This is the effect diagram of the planned spring straw burning disposal in Suihua City. (a) and (b) are the PM values ​​from March to April 2022. 2.5 The comparison chart of the number of fire points, (c) and (d) are the PM values ​​in March and April 2023. 2.5 The comparison chart of the number of fire points, (e) and (f) are the PM values ​​in March and April 2024. 2.5 and the comparison chart of the number of fire points;

[0025] Fig.12 PM for Suihua City in March and April 2022-2024 2.5 Daily average concentration graph. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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.

[0027] Embodiment 1

[0028] See also Figure 1-Figure 12 , a planned burning technology of straw residues shown in the figure includes the following steps:

[0029] Step 1: The provincial level issues a straw burning plan instruction. After receiving the instruction, each municipal ecological environment bureau determines the suitable conditions for straw burning. Specifically, it generates daily burning recommendations based on comprehensive factors such as air quality, wind speed, weather conditions and wind direction to ensure that straw burning meets environmental protection and safety requirements;

[0030] Step 2: Pre-assessment is the preparation for the disposal of straw residues after receiving the straw burning plan instruction from the Municipal Ecological Environment Bureau. In this stage, air quality control targets will be set and areas suitable for daily straw burning will be determined. Based on the generated model results, a spatial distribution map of the straw burning list will be drawn to show the geographical locations where the plan can be implemented, and a CSV file containing burning information will be output to screen out the optimal burning plan.

[0031] Step 3: Process supervision is to use multi-source data analysis, stereoscopic observation and model analysis to conduct real-time supervision and planning of key areas during the burning process, respond to various emergencies through emergency response mechanisms, and issue dynamic control suggestions;

[0032] Step 4: Post-evaluation is a summary after the straw disposal is completed. In this stage, an evaluation model will be used to conduct a comprehensive evaluation of the effects of this round of work, and feedback will be provided to the Municipal Ecological Environment Bureau on the results, problems and improvement measures to further improve the straw management plan and planned burning system.

[0033] Specifically, the screening and determination of areas suitable for straw burning: the R language is used to automatically download the meteorological data and air quality data for the next 7 days and organize them into Excel format. According to the downloaded data and the required straw burning amount reported by each district and county after consultation, the areas that can be burned and the burning recommendations for the next day are predicted, and a straw burning plan emission list is prepared. Among them, the screening principles and standards for planned straw burning are as follows: 1. Air quality level; judging the air quality level: when the air quality is excellent or good, consider burning; when the air quality is polluted (mild or above), burning is not allowed; 2. Wind speed level, judging the wind speed level: Level 3-5: burning is allowed when the air quality is excellent or good; Level 1-2 or greater than Level 6: burning is allowed when the air quality is excellent, and not allowed when the air quality is good; 3. Weather conditions, after meeting the air quality and wind speed conditions, judge the weather forecast for the day and the day before: when the weather is sunny or cloudy, burning is allowed; when the weather is raining or snowing, burning is not allowed; 4. Wind direction, after meeting the above conditions, judge whether the burning area is located downwind of the nearest urban main urban area or national control station: if it is upwind, burning is allowed; if it is downwind, manual further judgment is required whether burning is allowed.

[0034] Further, preliminary assessment of the impact of planned straw burning on air quality: Based on the planned straw burning emission inventory prepared in step 1, the air quality prediction model WRF-CMAQ is used to predict future air quality, see Figure 4 ,First, install and configure the air quality model WRF-CMAQ, initialize the system and ,detect the current program running environment, and install and ,configure WRF-CMAQ after it meets the running standards.

[0035] Prepare weather forecast data for the next two days to drive the WRF model, prepare basic anthropogenic emission inventories (MEIC) and biogenic emission inventories (Megan), and combine them with the planned straw burning emission inventory prepared in step 1. Set the model resolution to 3km, and the simulation time span covers the planned burning time (three to five days). Set up two groups of sensitivity tests, namely, sensitivity test 1: including anthropogenic emissions, biogenic emissions and planned straw burning emission scenarios; sensitivity test 2: only including anthropogenic emissions and biogenic emissions scenarios. The difference between the two represents the impact of planned straw burning on air quality. Simulate the two groups of sensitivity tests, output the spatiotemporal distribution of pollutant concentrations, and use tools such as NCL to analyze the impact of planned straw burning on PM 2.5 The impact of the burning process on the national control sites is determined by the concentration, and whether the impact of the burning process on the national control sites exceeds the standard. At the same time, the source analysis function is used to calculate the proportion of the impact of burning in each district and county on the national control sites, and further improve the straw burning plan.

[0036] In addition, supervision of the planned straw burning process is based on stereoscopic observation: based on the planned straw burning plan provided in Module 2, the district and county governments implement and issue burning instructions, and use stereoscopic observation technology for dynamic monitoring during the burning process, including the use of satellite remote sensing and video monitoring to observe straw burning fire points in real time, the use of ground-based lidar to observe vertical changes in pollutant concentrations and atmospheric boundary layer heights, and the use of UAVs and drones for on-site observations and sampling, so that management departments can promptly discover and effectively stop unplanned burning.

[0037] At the same time, real-time data from air quality monitoring stations and meteorological observation stations are used to monitor air quality and meteorological diffusion conditions to determine the actual combustion conditions on site. A variety of models (including WRF-CMAQ and HYSPLIT) are used to predict meteorological trajectories, regional transmission and concentration changes of pollutants, and the straw burning disposal plan is updated in real time to achieve maximum straw disposal and minimum air quality impact.

[0038] Post-evaluation of the impact of actual straw burning on air quality: Based on the above-mentioned planning of straw burning and supervision of the burning process, a post-evaluation of the impact of actual straw burning on air quality will be carried out, and a reference will be provided for the formulation of the burning plan the next day.

[0039] Prepare high-resolution meteorological reanalysis data (FNL) for the past three days, straw burning plan emission inventory (based on the collection of administrative village-level burning plan information reported by various districts and counties, including the location and intensity of the burning area (calculation of particulate matter emissions, module 2 has been prepared), basic emission inventory (human emission inventory MEIC, biogenic emission inventory Megan, module 2 has been prepared) and actual straw emission inventory (biomass burning emission inventory, and improved based on satellite fire point data, etc.), set WRF-CMAQ (resolution and simulation area are the same as module 2, model The time period is the past three days), and three groups of sensitivity tests are set: sensitivity test 1: planned straw burning scenario; sensitivity test 2: actual straw burning scenario; sensitivity test 3: no straw burning scenario. The difference between the simulation results of sensitivity test 1 and test 3 is the impact and contribution of the planned straw burning amount on air quality; the difference between the simulation results of sensitivity test 2 and test 3 is the impact and contribution of the actual straw burning amount on air quality; the difference between the simulation results of sensitivity test 2 and test 1 is the impact and contribution of the burning amount outside the straw burning plan on air quality.

[0040] After obtaining the simulation results of the three scenarios, the differences between the scenarios were calculated using tools such as NCL to determine the impact and scope of actual straw burning and burning other than planned burning on air quality. The CMAQ source analysis tool was used to quantitatively analyze the relative contribution of straw burning in each district and county to the national control stations. After summarizing the result charts, an assessment report on the impact of straw burning on air quality was generated. Based on the results, a reference basis was provided for formulating a straw burning plan the next day.

[0041] Specific implementation method 2: The application of the content described in this implementation method 1 in the spring straw burning plan in Suihua City, Heilongjiang Province, Figure 5 For this planned straw burning application area, the straw burning ban area was divided based on the local county administration and roads. According to the meteorological conditions and air quality levels in each area in the next three days, the Figure 6 After the government issues a burning order, it organizes each region to carry out planned straw burning. During the burning process, it uses tower video fire point monitoring system, satellite fire point monitoring technology, laser radar, driving vehicle and drone observation technology to implement process supervision. Figure 7 , for real-time analysis of air pollution incidents caused by straw burning Figure 8 , determine the source direction of pollutants and find the corresponding burning area for control, and then conduct a post-evaluation of the air quality during the planned straw burning period. Use WRF-CMAQ to obtain the effect of planned straw burning on PM 2.5 The temporal and spatial distribution of the concentration effect can be seen in Fig. 9 , based on the model simulation results, generate an analysis report see Fig.10 .

[0042] The present invention is a temporary measure before the full-scale comprehensive utilization of straw, which helps to reduce the degree of air pollution while alleviating the agricultural production pressure in typical agricultural cities. It has been verified in practice that Suihua City has implemented straw disposal according to the straw burning technology described in the present invention. Under the circumstances of obvious increase in pollutant emissions and overall deterioration of meteorological conditions, the degree of pollution has been effectively reduced. Specifically, PM2.5 in March-April 2024 was 1.347 million tons, 1.22 million tons of carbon dioxide, and 2.1 million tons of CO2. 2.5 The daily average concentration decreased by 4 μg / m compared with 2022 and 2023. 3 and 14.5 μg / m 3 ,See Fig.12 .

[0043] The present invention can quickly output a straw burning plan assessment report and submit it to management personnel, which helps management departments to promptly discover deficiencies, analyze the causes of pollution incidents, and quickly improve disposal plans, providing technical support for avoiding pollution incidents. It has been verified in practice that during the moderate pollution incident in Suihua City from April 10 to April 11, 2024, the present invention quickly analyzed the causes of the pollution incident and found that the stealing and rushing burning behaviors in the suburbs of Beilin District, Suihua City after the boundary layer was lowered at night had a significant impact on PM2.5. 2.5 The concentration contribution rate reached more than 80%. The local government responded promptly and strengthened the supervision of nighttime burning in the subsequent burning process, controlling the pollution caused by local illegal nighttime burning of straw in the later period. In addition, in a severe pollution incident from April 21 to April 22, 2024, this incident was mainly caused by the regional transmission of pollutants generated by large-scale burning of straw in Bayan County, Harbin, east of Beilin District, Suihua City, with a contribution rate of up to 70%.

[0044] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0045] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A planned burning technology for straw residues, characterized in that: The steps include: Step 1: The provincial level issues a straw burning plan instruction. After receiving the instruction, each municipal ecological environment bureau determines the suitable conditions for straw burning. Specifically, it generates daily burning recommendations based on comprehensive factors such as air quality, wind speed, weather conditions and wind direction to ensure that straw burning meets environmental protection and safety requirements; Step 2: Pre-assessment is the preparation for the disposal of straw residues after receiving the straw burning plan instruction from the Municipal Ecological Environment Bureau. In this stage, air quality control targets will be set and areas suitable for daily straw burning will be determined. Based on the simulation results of the model calculation, a spatial distribution map of the straw burning list will be drawn to show the geographical locations where the plan can be implemented, and a CSV file containing the burning information will be output to screen out the optimal burning plan. Step 3: Process supervision is to use multi-source data analysis, stereoscopic observation and model analysis to conduct real-time supervision and planning of key areas during the burning process, respond to various emergencies through emergency response mechanisms, and issue dynamic control suggestions; Step 4: Post-evaluation is a summary after the straw residue disposal is completed. In this stage, an evaluation model will be used to conduct a comprehensive evaluation of the effects of this round of work, and feedback on the results, problems and improvement measures will be provided to the Municipal Ecological Environment Bureau to further improve the straw management plan and planned burning system.

2. The planned burning technology of straw residues according to claim 1 is characterized in that: The step one specifically generates daily burning recommendations based on comprehensive factors such as air quality, wind speed, weather conditions and wind direction to ensure that straw burning meets environmental protection and safety requirements. The screening principle is that if the air quality in the districts and counties where the burning is planned is excellent or good, the wind speed level is 3-5, the burning area is downwind of the national control station, and the weather on the planned day and the previous day is sunny or cloudy, the burning work can be carried out as planned; if only some of the conditions are met, manual further judgment is required as to whether burning is allowed; if all of the conditions are not met, burning is not allowed in the area.

3. The planned burning technology of straw residues according to claim 2 is characterized in that: Specifically, the second step first collects the burning plan information at the administrative village level reported by each district and county, including the location and intensity of the burning area, etc., to estimate the emissions generated by this burning; secondly, WRF-CMAQ is used to simulate air quality in combination with existing meteorological forecast data, other emission inventories and other information, and the scenarios without straw burning and the scenarios containing the burning information reported by each district and county are calculated and compared for verification; then, the sensitivity analysis function of the CMAQ model is used to calculate the contribution ratio of straw burning to air quality in each district and county. Finally, based on the simulation results, a spatial distribution map of the straw burning inventory is drawn to show the geographical location where the plan can be implemented, and a CSV file containing the burning information is output to screen out the optimal burning plan.

4. The planned burning technology of straw residues according to claim 3 is characterized in that: The third step is to promptly detect air pollution and safety hazards when the planned burning is carried out, update the disposal plan in real time, ensure that the burning activities are carried out in an orderly manner and minimize their impact on air quality.

5. The planned burning technology of straw residues according to claim 4 is characterized in that: Specifically, the step 4 first obtains satellite fire point data and prepares a straw burning pollutant emission inventory; Secondly, WRF-CMAQ was used to simulate air quality in combination with existing meteorological reanalysis data, other emission inventory information, etc., and the scenarios of no straw burning, planned straw burning and actual straw burning were calculated and compared for verification. Then, the sensitivity analysis function of the CMAQ model was used to calculate the contribution ratio of each district and county to pollution. Finally, according to the model simulation results, corresponding charts of the actual straw burning situation and air quality were drawn to clarify the contribution of unplanned straw burning and quantify the impact of actual burning conditions in various places on air quality.

6. The planned burning technology of straw residues according to claim 5 is characterized in that: The second step is to implement a method for determining suitable conditions for straw burning at the county level based on R language programming and a pre-assessment model for the impact of straw burning on air quality based on WRF-CMAQ.

7. The planned burning technology of straw residues according to claim 6 is characterized in that: The step three is a method for supervising the planned straw burning process based on stereoscopic observation technology.

8. The planned burning technology of straw residues according to claim 7 is characterized in that: The step 4 is to implement a pre-assessment model of the impact of straw burning on air quality based on WRF-CMAQ and an automatic output program of the straw burning plan work report based on the Rmarkdown tool.

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