A method and electronic device for analyzing groundwater pollution sources based on multiple tracers

Abstract

The present invention belongs to the technical field of groundwater pollution source tracking, and specifically relates to a groundwater pollution source analysis method and electronic equipment based on multiple tracers. The method includes: setting monitoring points; obtaining concentration information of multiple tracers in groundwater; drawing spatial distribution maps of multiple tracers; determining initial key pollution areas and initial migration and diffusion areas; simulating the historical pollution state of groundwater according to the groundwater fluid model; simulating the historical key pollution areas and historical migration and diffusion areas of groundwater in combination with the initial key pollution areas and the initial migration and diffusion areas; determining the pollution source and migration and diffusion direction according to the changes in the historical key pollution areas and the historical migration and diffusion areas. The present invention introduces groundwater flow information, and the location of the pollution source is determined accurately, and there is no need to place fluorescent tracers, and there is no impact on groundwater.

Description

Technical Field

[0001] The present invention belongs to the technical field of groundwater pollution source tracking, and in particular relates to a groundwater pollution source analysis method and electronic equipment based on multiple tracers. Background Art

[0002] Groundwater is an important part of water resources. At present, groundwater in different layers in some areas is suffering from environmental pressure of pollution. The pollution sources mainly come from industrial pollution, agricultural pollution and domestic sewage. The strata below the surface are complex. Once groundwater is polluted, it is difficult to find it in time. Even if it is found, the pollutants in the groundwater have spread and it is difficult to find the source of pollution, which makes groundwater treatment difficult.

[0003] The technology for tracing the pollution source of groundwater is mainly based on water sample collection and component analysis, and the pollutant concentration in the water sample is compared and analyzed to determine the pollution source by the change of pollutant concentration. For example, the prior art CN117451962A discloses a method, device and electronic equipment for tracing the source of groundwater pollution, which includes: determining the monitoring well group according to the site conditions; obtaining water samples in the monitoring well group, detecting and analyzing the characteristic pollutant concentration in the water sample, and determining the key pollution area and migration and diffusion area; placing fluorescent tracers in the key monitoring wells in the key pollution area and migration and diffusion area, and detecting the tracer concentration; according to the acquired characteristic pollutant concentration and fluorescent tracer concentration detection data, the pollutant concentration distribution and the tracer concentration distribution are simulated and analyzed by concentration gradient to obtain the tracing result.

[0004] The existing technology for tracing pollution sources has the following problems: the release of fluorescent tracers will affect the groundwater quality and even the pollutant concentration, affecting the analysis results; groundwater is in a flowing state, and there is a certain error in confirming the pollution area and the diffusion area based on the static state detection results; when there are multiple pollution sources, there is overlap of pollutants, and the pollution source is confirmed based on the static state detection results, and the analysis results have a certain deviation from the actual situation. Summary of the invention

[0005] In order to solve at least one of the above-mentioned technical problems existing in the prior art, the present invention provides a groundwater pollution source analysis method and electronic equipment based on multiple tracers.

[0006] To achieve the above object, the technical solution of the present invention is as follows:

[0007] In one aspect, the present invention provides a method for analyzing groundwater pollution sources based on multiple tracers, comprising:

[0008] S1. Set monitoring points in the area to be detected;

[0009] S2. Obtain groundwater samples from the monitoring points and obtain concentration information of multiple tracers in the water samples;

[0010] S3. Draw spatial distribution maps of multiple tracers based on concentration information of multiple tracers;

[0011] S4. Determine the initial key pollution area and initial migration and diffusion area based on the spatial distribution maps of multiple tracers;

[0012] S5. Based on the groundwater fluid model, simulate the historical pollution state of groundwater; combine the initial key pollution area and the initial migration and diffusion area to simulate the historical key pollution area and historical migration and diffusion area of ​​groundwater;

[0013] S6. Determine the pollution sources and migration and diffusion directions based on changes in historical key pollution areas and historical migration and diffusion areas.

[0014] Furthermore, the monitoring point extracts groundwater samples in situ with low disturbance.

[0015] Furthermore, when the distance between adjacent monitoring points is greater than the distance threshold, one or more new monitoring points are added at the middle position of the adjacent existing monitoring points, and finally the shortest distance between the adjacent monitoring points is less than the distance threshold.

[0016] Furthermore, the tracer is an indicator pollutant, such as heavy metal pollutants, nitrogen, phosphorus and potassium, pesticides, organic compounds, nitrates, etc.

[0017] Furthermore, in step S4, the initial key pollution area and the initial migration and diffusion area are determined according to the spatial distribution maps of multiple tracers, specifically including: taking the monitoring points with pollutant concentration greater than the first concentration threshold as the key pollution monitoring points, and taking the key pollution monitoring points as the center and the circle range defined by the set distance R1 as the radius as the initial key pollution area; taking the monitoring points with pollutant concentration less than or equal to the first concentration threshold and greater than the second concentration threshold as the migration and diffusion monitoring points, and taking the migration and diffusion monitoring points as the center and the circle range defined by the set distance R2 as the radius as the initial migration and diffusion area.

[0018] Furthermore, the method for determining the distance R1 is: 0.5 times the distance between the key pollution monitoring point and the adjacent migration and diffusion monitoring point is taken as the distance R1.

[0019] Furthermore, the distance R2 is determined by: 0.5 times the distance between the migration and diffusion monitoring point and the adjacent ordinary monitoring point, where the ordinary monitoring point is a monitoring point that is neither a key pollution monitoring point nor a migration and diffusion monitoring point.

[0020] Furthermore, step S5 specifically includes:

[0021] A groundwater fluid model is established based on the flow velocity of groundwater collected at the monitoring points. The flow direction in the groundwater fluid model is the opposite direction of the flow direction of the collected groundwater. The tracer concentration and groundwater flow velocity of each monitoring point are input into the groundwater fluid model to simulate the historical pollution state of groundwater; until the initial migration and diffusion area in the groundwater is smaller than the threshold range.

[0022] Furthermore, the groundwater pollution source analysis method also includes:

[0023] S7. Obtain the types and concentrations of pollutants in the initial key pollution areas, obtain the types and concentrations of pollutants in the pollution sources obtained in step S6, compare the two, and determine the reduced types of pollutants; obtain the corresponding initial key pollution areas according to the reduced types of pollutants, and use the groundwater fluid model again to simulate the historical pollution state corresponding to the pollutant until the initial migration and diffusion area of ​​the pollutant is less than the threshold range. At this time, the location with the highest pollutant concentration is the missed pollution source.

[0024] Furthermore, the groundwater pollution source analysis method further includes: calculating the contribution rate of different pollution sources to the types of pollutants reduced in step S7 according to the omitted pollution sources, which is:

[0025]

[0026] in, is the contribution rate of the kth pollution source to the reduction of pollutant types, k is a number between 1 and n, and n is the number of omitted pollution sources. is the concentration of the pollutant type currently reduced by the kth pollution source, is the concentration of the pollutant type currently reduced by the i-th pollution source.

[0027] In another aspect, the present invention further provides an electronic device, comprising:

[0028] processor, and

[0029] A memory having a computer program stored therein, which, when executed by the processor, implements the above-mentioned groundwater pollution source analysis method based on multiple tracers.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The method for analyzing groundwater pollution sources based on multiple tracers provided by the present invention draws spatial distribution maps of multiple tracers according to the concentration information of the tracers, then determines the initial key pollution area and the migration and diffusion area, and then uses the groundwater fluid model to simulate the historical pollution state of the groundwater, and determines the pollution source according to the historical pollution state. The present invention introduces groundwater flow information, and the location of the determined pollution source is accurate, and there is no need to release fluorescent tracers, which has no impact on the groundwater.

[0032] The present invention uses the initial key pollution areas and the final pollution sources to determine the types of pollutants to be reduced, and then uses the groundwater fluid model to analyze the missed pollution sources and improve the accuracy of tracing the source. At the same time, it also calculates the contribution rate of different pollution sources to the same pollutant, providing data support for pollution control. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0034] The technical solution of the present invention will be clearly described below in conjunction with the accompanying drawings. Obviously, the described embodiments are not all embodiments of the present invention, and all other embodiments obtained by ordinary technicians in the field without making creative work are within the protection scope of the present invention.

[0035] It should be noted that, unless otherwise specifically stated, the relative arrangements of components and steps, and numerical expressions set forth in these embodiments should not be construed as limiting the scope of the present invention.

[0036] The following description of the exemplary embodiments is merely illustrative and is not intended to limit the present invention and its application or use in any sense. Techniques, methods and devices known to ordinary technicians in the relevant field may not be discussed in detail here, but where applicable, these techniques, methods and devices should be considered as part of this specification.

[0037] Embodiment 1

[0038] This embodiment provides a method for analyzing groundwater pollution sources based on multiple tracers, such as Figure 1 As shown, including:

[0039] S1. Set monitoring points in the area to be detected;

[0040] The monitoring point extracts groundwater samples in situ with low disturbance. If the groundwater level is shallow, a pushpoint can be used to extract samples with the help of a peristaltic pump. If the groundwater level is deep, a portable mobile small drilling rig can be used to drill holes for sampling. The direct extraction sampling method can directly obtain groundwater samples, making the water sample analysis results closer to the actual groundwater source situation and improving the analysis accuracy of the pollution source.

[0041] When the distance between adjacent monitoring points is greater than the distance threshold, one or more new monitoring points are added in the middle of the adjacent existing monitoring points, and the shortest distance between the adjacent monitoring points is less than the distance threshold. The distance threshold is determined based on the depth of the groundwater source, historical pollution, and the nearby living environment and number of factories. It is determined in the following way:

[0042]

[0043] In the above formula, c is the correction coefficient, Indicates the historical pollution level, Indicates the depth of groundwater source, represents the number of factories near the groundwater source, and S represents the population density near the groundwater source.

[0044] Where c is any number between 0.6 and 1, and its value depends on the area of ​​the groundwater pollution source analysis area and the rainfall in the area. It is determined by the concentration ratio of pollution sources in historical data, specifically the average concentration ratio of all pollution sources in historical water samples. N is the number of factories in the groundwater pollution source analysis area, and S is the population density in the groundwater pollution source analysis area.

[0045] S2. Obtain groundwater samples from the monitoring points and obtain concentration information of multiple tracers in the water samples;

[0046] Among them, the tracer is an indicator pollutant, such as heavy metal pollutants, nitrogen, phosphorus and potassium, pesticides, organic compounds, nitrates, etc. Heavy metal pollutants are usually present in chemical plants, such as mercury. Mercury and its compounds mainly come from instrument factories, salt electrolysis, precious metal smelting, cosmetics, coal burning, lighting, etc. Cadmium mainly comes from wastewater from electroplating, mining, smelting, battery and other factories. Lead mainly comes from the emissions from factories that prepare products such as paints, coatings, hardware, hair dyes, tableware, etc. There are also arsenic, chromium, copper, zinc, etc. The specific heavy metal used as a tracer can be determined according to the factory conditions in the analysis area.

[0047] Nitrogen, phosphorus and potassium mainly come from fertilizers in farmland. Therefore, the content of nitrogen, phosphorus and potassium can be used as tracers for the analysis of groundwater pollution sources in fields. Pesticides are the same as nitrogen, phosphorus and potassium, and also come from farmland management. Whether a typical component in pesticides should be used as a tracer can be determined based on whether the groundwater passes through the farmland.

[0048] Organic compounds include natural organic compounds and artificially synthesized organic compounds. Natural organic compound pollutants mainly come from wastewater from the petrochemical industry, such as benzene, formaldehyde, etc.

[0049] Nitrate pollution uses nitrogen and oxygen isotopes as tracers and mainly comes from human sewage.

[0050] S3. Draw spatial distribution maps of multiple tracers based on their concentration information. The spatial distribution map is based on satellite maps. The concentration information of the tracers is filled onto the satellite maps with each monitoring point as the center to form spatial distribution maps of multiple tracers. The concentration information of each tracer is filled in batches to finally obtain a superimposed spatial distribution map.

[0051] S4. Determine the initial key pollution area and initial migration and diffusion area based on the spatial distribution maps of multiple tracers;

[0052] Specifically, it includes: taking the monitoring points where the pollutant concentration is greater than the first concentration threshold as the key pollution monitoring points, and taking the key pollution monitoring points as the center and the circle range with the set distance R1 as the radius as the initial key pollution area; taking the monitoring points where the pollutant concentration is less than or equal to the first concentration threshold and greater than the second concentration threshold as the migration and diffusion monitoring points, and taking the migration and diffusion monitoring points as the center and the circle range with the set distance R2 as the radius as the initial migration and diffusion area.

[0053] The first concentration threshold and the second concentration threshold are set as needed. For example, the first concentration threshold is set to 30%, and the second concentration threshold is set to 20%.

[0054] Among them, the method for determining the distance R1 is: 0.5 times the distance between the key pollution monitoring point and the adjacent migration and diffusion monitoring point is taken as the distance R1.

[0055] The method for determining the distance R2 is: 0.5 times the distance between the migration and diffusion monitoring point and the adjacent ordinary monitoring point. The ordinary monitoring point is a monitoring point that is neither a key pollution monitoring point nor a migration and diffusion monitoring point.

[0056] S5. Based on the groundwater fluid model, simulate the historical pollution state of groundwater; combine the initial key pollution area and the initial migration and diffusion area to simulate the historical key pollution area and historical migration and diffusion area of ​​groundwater;

[0057] Specifically, a groundwater fluid model is established based on the flow velocity of groundwater collected at monitoring points. Since the contribution of groundwater convection and diffusion to the migration distance of pollutant solutes is very small, the effects of convection and diffusion are not considered in the groundwater fluid model, and only the flow of groundwater itself is considered.

[0058] The water flow direction in the groundwater fluid model is the opposite direction of the collected groundwater flow direction; the tracer concentration and groundwater flow velocity of each monitoring point are input into the groundwater fluid model to simulate the historical pollution state of groundwater; until the initial migration and diffusion area in the groundwater is smaller than the threshold range. Among them, the threshold range can be expressed by area. Due to the flow of groundwater, the pollution source will move or shift with the flow of groundwater over time, resulting in deviations in the determination of the pollution source. Through reverse simulation, the pollution source gradually approaches the original pollution source, and then the real pollution source can be determined.

[0059] S6. Determine the pollution sources and migration and diffusion directions based on changes in historical key pollution areas and historical migration and diffusion areas.

[0060] During the simulation, the initial migration diffusion area gradually shrinks and gradually approaches the real pollution source. When the initial migration diffusion area is smaller than the threshold range, the monitoring point with a pollutant concentration greater than the first concentration threshold is used as a key pollution monitoring point, and the circle with the key pollution monitoring point as the center and the set distance R1 as the radius is the real pollution source. The migration diffusion direction is determined according to the change of the initial migration diffusion area during the simulation, and the opposite direction of the direction in which the initial migration diffusion area gradually shrinks is the migration diffusion direction.

[0061] S7. Obtain the types and concentrations of pollutants in the initial key pollution areas, obtain the types and concentrations of pollutants in the pollution sources obtained in step S6, compare the two, and determine the reduced types of pollutants; obtain the corresponding initial key pollution areas according to the reduced types of pollutants, and use the groundwater fluid model again to simulate the historical pollution state corresponding to the pollutant until the initial migration and diffusion area of ​​the pollutant is less than the threshold range. At this time, the location with the highest pollutant concentration is the missed pollution source.

[0062] Furthermore, the groundwater pollution source analysis method further includes: calculating the contribution rate of different pollution sources to the types of pollutants reduced in step S7 according to the omitted pollution sources, which is:

[0063]

[0064] in, is the contribution rate of the kth pollution source to the reduction of pollutant types, k is a number between 1 and n, and n is the number of omitted pollution sources. is the concentration of the pollutant type currently reduced by the kth pollution source, is the concentration of the pollutant type currently reduced by the i-th pollution source.

[0065] Embodiment 2

[0066] This embodiment provides an electronic device, including:

[0067] processor, and

[0068] A memory having a computer program stored thereon, wherein when the computer program is executed by the processor, the groundwater pollution source analysis method based on multiple tracers provided in the first embodiment is implemented.

[0069] The above specific implementation methods are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to examples, a person skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A method for analyzing groundwater pollution sources based on multiple tracers, characterized in that: include: S1. Set monitoring points in the area to be detected; S2. Obtain groundwater samples from the monitoring points and obtain concentration information of multiple tracers in the water samples; S3. Draw spatial distribution maps of multiple tracers based on concentration information of multiple tracers; S4. Determine the initial key pollution area and initial migration and diffusion area based on the spatial distribution maps of multiple tracers; S5. Based on the groundwater fluid model, simulate the historical pollution state of groundwater; combine the initial key pollution area and the initial migration and diffusion area to simulate the historical key pollution area and historical migration and diffusion area of ​​groundwater; Specifically include: According to the flow velocity of groundwater collected at the monitoring points, a groundwater fluid model is established. The flow direction in the groundwater fluid model is the opposite direction of the flow direction of the collected groundwater. The tracer concentration and groundwater flow velocity of each monitoring point are input into the groundwater fluid model to simulate the historical pollution state of groundwater until the initial migration and diffusion area in the groundwater is less than the threshold range. S6. Determine the pollution sources and migration and diffusion directions based on the changes in historical key pollution areas and historical migration and diffusion areas; S7. Obtain the types and concentrations of pollutants in the initial key pollution areas, obtain the types and concentrations of pollutants in the pollution sources obtained in step S6, compare the two, and determine the reduced types of pollutants; obtain the corresponding initial key pollution areas according to the reduced types of pollutants, and use the groundwater fluid model again to simulate the historical pollution state corresponding to the pollutant until the initial migration and diffusion area of ​​the pollutant is less than the threshold range. At this time, the location with the highest pollutant concentration is the missed pollution source.

2. The method for analyzing groundwater pollution sources according to claim 1, characterized in that: When the distance between adjacent monitoring points is greater than the distance threshold, one or more new monitoring points are added in the middle of the adjacent existing monitoring points, and finally the shortest distance between adjacent monitoring points is less than the distance threshold.

3. The method for analyzing groundwater pollution sources according to claim 1, characterized in that: The tracer is an indicator pollutant.

4. The method for analyzing groundwater pollution sources according to claim 1, characterized in that: In step S4, the initial key pollution area and the initial migration and diffusion area are determined according to the spatial distribution maps of multiple tracers, specifically including: taking the monitoring points where the pollutant concentration is greater than the first concentration threshold as the key pollution monitoring points, and taking the key pollution monitoring points as the center and the circle range defined by the set distance R1 as the radius as the initial key pollution area; taking the monitoring points where the pollutant concentration is less than or equal to the first concentration threshold and greater than the second concentration threshold as the migration and diffusion monitoring points, and taking the migration and diffusion monitoring points as the center and the circle range defined by the set distance R2 as the radius as the initial migration and diffusion area.

5. The method for analyzing groundwater pollution sources according to claim 4, characterized in that: The method for determining the distance R1 is: 0.5 times the distance between the key pollution monitoring point and the adjacent migration and diffusion monitoring point is taken as the distance R1.

6. The method for analyzing groundwater pollution sources according to claim 4, characterized in that: The method for determining the distance R2 is: 0.5 times the distance between the migration and diffusion monitoring point and the adjacent ordinary monitoring point. The ordinary monitoring point is a monitoring point that is neither a key pollution monitoring point nor a migration and diffusion monitoring point.

7. The method for analyzing groundwater pollution sources according to claim 1, characterized in that: The groundwater pollution source analysis method further includes: calculating the contribution rate of different pollution sources to the types of pollutants reduced in step S7 according to the omitted pollution sources, which is: in, is the contribution rate of the kth pollution source to the reduction of pollutant types, k is a number between 1 and n, and n is the number of omitted pollution sources. is the concentration of the pollutant type currently reduced by the kth pollution source, is the concentration of the pollutant type currently reduced by the i-th pollution source.

8. An electronic device, comprising: processor, and A memory having a computer program stored thereon, characterized in that when the computer program is executed by the processor, the method for analyzing groundwater pollution sources based on multiple tracers as described in any one of claims 1 to 7 is implemented.

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