A method and system for risk assessment of perfluorinated compounds
By decomposing the decay process of perfluorinated compounds in groundwater into independent physical mechanisms, and combining a steady-state pollution transport analytical model and minimum partition set analysis, the complexity and inaccuracy of perfluorinated compound assessment in existing technologies are solved, achieving high-precision risk assessment under conditions of limited or changing data.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- TECH CENT FOR SOIL AGRI & RURAL ECOLOGY & ENVIRONMENT MINIST OF ECOLOGY & ENVIRONMENT
- Filing Date
- 2026-04-16
- Publication Date
- 2026-07-14
AI Technical Summary
Existing groundwater solute transport models have high parameter requirements, are computationally complex, and are sensitive to input parameters when assessing perfluorinated compound (PFAS) pollutants, resulting in inaccurate assessment results. In particular, when the number of parameters is insufficient or groundwater quality changes, the model fails and cannot accurately reflect the migration and release behavior of PFAS.
The attenuation process of pollutants in groundwater is decomposed into two relatively independent physical mechanisms. Through steady-state pollutant transport analytical model and minimum partition set analysis, combined with Monte Carlo simulation, an analytical solution model based on physical mechanisms is constructed. The degradation term is discarded, and the characteristic cutoff length is used to describe the adsorption and incomplete reversible desorption into the error function and exponential function, simplifying the calculation process.
It improves the accuracy and interpretability of perfluorinated compound risk assessment, enabling preliminary screening with limited data and accurate assessment with sufficient data, reflecting network complexity and the diversity of pollution transmission pathways, and increasing tolerance for data gaps.
Smart Images
Figure CN122392677A_ABST
Abstract
Description
[Technical Field] This invention belongs to the field of data processing technology, and in particular relates to a risk assessment method and system for perfluorinated compounds. [Background Technology] Groundwater is the most important drinking water source in many parts of the world. Perfluorinated compounds (PFAS) can enter groundwater through soil infiltration, surface water recharge, or point source leakage, and can remain stable for a long time, migrating with water flow and forming large-scale pollution plumes. Many traditional pollutant monitoring standards are at the ppb (micrograms per liter) to ppm (milligrams per liter) level. However, due to the potent chronic toxicity of PFAS, their safety thresholds are much stricter; for example, the EPA's recommended drinking water health values for PFOA / PFOS are 4-20, indicating a high risk. This requires extremely high sensitivity in analytical chemistry and places unprecedentedly stringent demands on laboratory quality control and background contamination control during sampling. Even minor contamination can lead to significant deviations in results. Furthermore, the migration behavior of PFAS in groundwater is complex, and contamination boundaries are difficult to determine empirically. Risk assessment can calculate the level at which pollution concentrations need to be reduced to bring the risk down to an acceptable range. Simultaneously, by comparing the risk levels of different contaminated areas to sensitive receptors, it helps managers prioritize the allocation of limited resources and implement the most urgent response measures for the highest-risk areas.
[0003] The behavior of PFAS in groundwater differs fundamentally from that of traditional pollutants such as benzene compounds and heavy metals, making their monitoring and remediation exceptionally difficult. Their migration is characterized by extreme persistence and high mobility; their CF bonds are extremely strong, making them virtually impossible to degrade naturally by microorganisms or chemicals. Short-chain PFAS, in particular, are highly water-soluble and readily migrate long distances with groundwater flow, forming massive pollution plumes far exceeding the range of traditional pollutants. PFAS molecules are hydrophilic at one end and hydrophobic at the other, making them both soluble in water and strongly adsorbed by organic carbon and minerals in the soil. This adsorption is not entirely reversible, and the adsorption intensity varies with carbon chain length and soil conditions. When groundwater quality changes, such as pH and salinity, adsorbed PFAS may be released again, becoming a long-term source of secondary pollution, leading to pollution persisting for decades. Existing groundwater solute transport models, such as MT3DMS, are important tools for analyzing the migration of pollutants like PFAS. However, directly using uncustomized traditional models is often inaccurate. Models specifically enhanced to address the physicochemical properties of PFAS are needed. Analytical solute transport models are mathematically exact solutions based on physical equations, describing the concentration at any point in space at any time as a function of initial and boundary conditions. By decoupling processes, convection, dispersion, adsorption, and reaction processes are clearly distinguished and independently parameterized, ultimately outputting a concentration distribution map. However, these models may be too complex or data-intensive, requiring multiple types of input parameters such as pore flow velocity v, dispersion degree D, retardation factor R, and reaction rate λ. They are also sensitive to input parameters, requiring more data for calibration, making calculations relatively complex. Insufficient calibration can lead to less reliable results. Furthermore, when the acidity conditions in the underground region change, the adsorbed PFAS in the area through which the groundwater flows may be released again, and this release will cause the exact solution model to fail. Therefore, for perfluorinated compound risk assessment in cases with insufficient parameters, large target monitoring areas, and obvious adsorption and release characteristics, a direct or compromise solution is required. Based on the above problems, this invention decomposes the attenuation process of pollutants in groundwater into two relatively independent physical mechanisms, and provides a minimum partition set for analyzing the pollution network from a graph theory perspective to discover the risks brought about by adsorption and release in the propagation path of fluorinated compounds. It can reflect the complexity of the network and the diversity of potential pollution propagation paths, and has a high tolerance for missing data. Furthermore, the confidence interval of the assessment results is obtained by using a steady-state pollution transport analytical model in conjunction with Monte Carlo simulation to improve the assessment accuracy and interpretability. [Summary of the Invention] To address the aforementioned problems in the prior art, this invention proposes a risk assessment method and system for perfluorinated compounds, the method comprising: Step S1: Divide the target area into a grid and place the grid fingerprint into the grid matrix at the position corresponding to the grid position; Step S2: Construct a gridded steady-state pollution transport analytical model to quantitatively characterize the concentration transfer and decay relationship of pollutants between upstream and downstream grids; abandon the degradation term for PFAS end products and construct an analytical solution model based on physical mechanisms, and use the characteristic cutoff length to comprehensively characterize the mass loss of aqueous PFAS caused by adsorption retardation and incomplete reversible desorption. Step S3: Find all minimum partition sets of the target grid based on the grid matrix; the minimum partition set is one where all paths from any grid containing a pollution source to the target grid pass through at least one grid in the minimum partition set; determine the available minimum partition sets from the minimum partition sets; for each minimum partition set, if the monitoring data of each grid in it is available, then it is considered an available minimum partition set; Step S4: Calculate the predicted grid concentration of the target grid corresponding to the available minimum partition set based on each available minimum partition set and the steady-state pollution transport analytical model; determine the risk assessment result based on the predicted grid concentration obtained from each available minimum partition set.
[0005] Furthermore, the grid concentration includes the concentration of various PFAS.
[0006] Furthermore, the constructed steady-state pollution transport analytical model is shown in equation (1); where: Let (i,j) be the concentration of the (i,j)th grid. For the first Mesh concentration, (i,j) mesh is The upstream grid of the grid; Refers to the transition from grid (i,j) to grid. The straight-line horizontal distance between them; It is the lateral dispersion; It is the pore flow velocity, which is the true average velocity at which pollutants move with groundwater; W is the width of the pollution source when the grid is used as the pollution source; characteristic interception length. It describes the intensity at which pollutants are retained in the strata due to adsorption; erf() is the error function, and exp() is the exponential function; (1).
[0007] Furthermore, the grid containing the location to be assessed is determined from the obtained risk assessment request as the target grid; the target grid identifier is obtained, and the directed connection relationships between grids in the grid matrix based on the target grid identifier are used to obtain all minimum partition sets for the target grid.
[0008] Furthermore, step S4 specifically involves: sequentially obtaining the available minimum partition set. One grid in Based on the grid concentration and the steady-state pollution transport analytical model, the predicted grid concentration of the target grid is calculated; the mean of the predicted grid concentration based on the flow ratio is used as the predicted grid concentration of the target grid corresponding to the available minimum partition set. Risk assessment results are determined based on the differences between each available minimum partition set; significant differences indicate high risk, while insignificant differences indicate low risk. Wherein: K is the number of available minimum partition sets.
[0009] Furthermore, when there is a first preset proportion of predicted grid concentration greater than the first preset predicted grid concentration, or when there is a second preset proportion of predicted grid concentration greater than the second preset predicted grid concentration, the risk is determined to be high; otherwise, the risk is determined to be low.
[0010] Furthermore, it also includes step S5: issuing an early warning based on the risk assessment results.
[0011] Furthermore, for a target grid, its minimum partition set changes dynamically at different risk assessment request times.
[0012] A risk assessment system for perfluorinated compounds includes a processor coupled to a memory storing program instructions. When the program instructions stored in the memory are executed by the processor, the risk assessment method for perfluorinated compounds is implemented.
[0013] A computer-readable storage medium includes a program that, when run on a computer, causes the computer to perform the risk assessment method for the perfluorinated compounds.
[0014] Based on the same inventive concept, the present invention also provides a computer-readable storage medium, characterized in that it includes a program that, when run on a computer, causes the computer to perform the above-described risk assessment method for perfluorinated compounds.
[0015] The beneficial effects of this invention include: The degradation process of pollutants in groundwater is decomposed into two relatively independent physical mechanisms: the error function term describes the dilution caused by lateral diffusion, and the exponential term describes the mass loss caused by adsorption and retention. The degradation term is discarded, which is more in line with the actual propagation behavior of recalcitrant pollutants such as PFAS. It does not require complex numerical solution tools and can be implemented in Excel or a simple programming environment. It can be used for preliminary screening with limited data, and can also be used for more accurate assessment when there is sufficient data. It provides a minimum partition set for analyzing pollution networks from a graph theory perspective to discover the superimposed risks caused by the adsorption and release of non-polluting sources in the propagation pathways of fluorinated compounds. It can reflect the complexity of the network and the diversity of potential pollution propagation pathways, and has a high tolerance for missing data. Furthermore, it improves the accuracy and interpretability of the assessment by obtaining confidence intervals of the assessment results through a steady-state pollution transport analytical model combined with Monte Carlo simulation. [Attached Image Description] The accompanying drawings, which are provided to further illustrate the invention and form part of this application, are not intended to unduly limit the invention. In the drawings: Figure 1 A schematic diagram illustrating the risk assessment method for perfluorinated compounds provided by this invention.
[0017] Figure 2 This is a schematic diagram of the minimum partition set of the groundwater flow field provided by the present invention.
Detailed Implementation Methods
[0019] Based on the same inventive concept, the present invention also provides a computer-readable storage medium, characterized in that it includes a program that, when run on a computer, causes the computer to perform the above-described risk assessment method for perfluorinated compounds.
[0020] A computer program (also referred to as a program, software, software application, script, or code) can be written in any form of programming language, including assembly or interpreted languages, declarative or procedural languages, and can be deployed in any form, including as a standalone program or as a module, component, subroutine, object, or other unit suitable for use in a computing environment. A computer program may, but does not necessarily, correspond to a file in a file system. A program can be stored as part of a file that holds other programs or data (e.g., one or more scripts stored in a markup language document), in a single file dedicated to said program, or in multiple co-located files (e.g., a file storing one or more modules, subroutines, or code portions). A computer program can be deployed to execute on a single computer or on multiple computers located at a single site or distributed across multiple sites and interconnected by a communications network.
[0021] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.
[0022] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.
[0023] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.
[0024] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.
[0025] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.
Claims
1. A risk assessment method for perfluorinated compounds, characterized in that, The method includes: Step S1: Divide the target area into a grid and place the grid fingerprint into the grid matrix at the position corresponding to the grid position; Step S2: Construct a gridded steady-state pollution transport analytical model to quantitatively characterize the concentration transfer and decay relationship of pollutants between upstream and downstream grids; abandon the degradation term for PFAS end products and construct an analytical solution model based on physical mechanisms, and use the characteristic cutoff length to comprehensively characterize the mass loss of aqueous PFAS caused by adsorption retardation and incomplete reversible desorption. Step S3: Find all minimum partition sets of the target grid based on the grid matrix; the minimum partition set is one where all paths from any grid containing a pollution source to the target grid pass through at least one grid in the minimum partition set; determine the available minimum partition sets from the minimum partition sets; for each minimum partition set, if the monitoring data of each grid in it is available, then it is considered an available minimum partition set; Step S4: Calculate the predicted grid concentration of the target grid corresponding to the available minimum partition set based on each available minimum partition set and the steady-state pollution transport analytical model; determine the risk assessment result based on the predicted grid concentration obtained from each available minimum partition set.
2. The risk assessment method for perfluorinated compounds according to claim 1, characterized in that, The grid concentration includes the concentration of various PFAS.
3. The risk assessment method for perfluorinated compounds according to claim 2, characterized in that, The constructed steady-state pollution transport analytical model is shown in equation (1); where: Let (i,j) be the concentration of the (i,j)th grid. For the first Mesh concentration, (i,j) mesh is The upstream grid of the grid; Refers to the transition from grid (i,j) to grid. The straight-line horizontal distance between them; It is the lateral dispersion; It is the pore flow velocity, which is the true average velocity at which pollutants move with groundwater; W is the width of the pollution source when the grid is used as the pollution source; characteristic interception length. It describes the intensity at which pollutants are retained in the strata due to adsorption; erf() is the error function, and exp() is the exponential function; (1)。 4. The risk assessment method for perfluorinated compounds according to claim 3, characterized in that, The grid containing the location to be assessed is determined from the obtained risk assessment request and designated as the target grid. Obtain the target mesh identifier, and based on the directed connectivity between meshes in the mesh matrix of the target mesh identifier, obtain all minimum partition sets for the target mesh.
5. The risk assessment method for perfluorinated compounds according to claim 4, characterized in that, Step S4 specifically involves: sequentially obtaining the available minimum partition set. One grid in Based on the grid concentration and the steady-state pollution transport analytical model, the predicted grid concentration of the target grid is calculated; the mean of the predicted grid concentration based on the flow ratio is used as the predicted grid concentration of the target grid corresponding to the available minimum partition set. Risk assessment results are determined based on the differences between each available minimum partition set; significant differences indicate high risk, while insignificant differences indicate low risk. Wherein: K is the number of available minimum partition sets.
6. The risk assessment method for perfluorinated compounds according to claim 5, characterized in that, When the predicted grid concentration of a first preset ratio is greater than the first preset predicted grid concentration, or when the predicted grid concentration of a second preset ratio is greater than the second preset predicted grid concentration, the risk is determined to be high; otherwise, the risk is determined to be low.
7. The risk assessment method for perfluorinated compounds according to claim 6, characterized in that, It also includes step S5: issuing an early warning based on the risk assessment results.
8. The risk assessment system for perfluorinated compounds according to claim 6, characterized in that, For a target grid, its minimum partition set changes dynamically at different risk assessment request times.
9. A risk assessment system for perfluorinated compounds, characterized in that, The method includes a processor coupled to a memory storing program instructions that, when executed by the processor, implement the risk assessment method for perfluorinated compounds as described in any one of claims 1-8.
10. A computer-readable storage medium, characterized in that, Includes a program, which, when run on a computer, causes the computer to perform the risk assessment method for perfluorinated compounds as described in any one of claims 1-8.