Method and system for acquiring parameters in reactive seepage dissolution and precipitation process and medium

Abstract

The invention discloses a parameter acquisition method and system for a reactive seepage dissolution and precipitation process and a medium. Relates to the technical field of geological storage. Carrying out a reactive seepage test, and collecting image data and seepage pressure data in real time; preprocessing the image data, and analyzing and calculating the variation of precipitation pixel points and the precipitation amount in the reactive seepage process; inputting the variation of the precipitation pixel points and the seepage pressure data into a constructed precipitation parameter relation model to obtain precipitation process parameters; according to the scheme, a carbon dioxide geological storage project is guided based on the precipitation process parameters, and real-time calculation of the porosity and the permeability in the reactive seepage dissolution precipitation process is realized based on a constructed precipitation parameter relation model through real-time image acquisition and real-time pressure monitoring of a reactive seepage test; the method has the advantages of being easy to operate, few in process, low in cost, high in precision and good in timeliness.

Description

Technical Field

[0001] This invention relates to the field of geological storage technology, specifically to a method, system, and medium for obtaining parameters of reactive seepage dissolution and precipitation processes. Background Technology

[0002] Reactive seepage and dissolution-precipitation processes are widely involved in natural processes and energy, environmental, and water conservancy projects, including carbonate dissolution-precipitation, reservoir seepage control and safety management, carbon dioxide geological sequestration, groundwater pollution and remediation, and microbial reinforcement technologies. Chemical reactions not only alter the solute transport patterns during seepage but can also trigger complex dissolution-precipitation processes, transforming the original system into a reactive multiphase seepage system with more complex physicochemical mechanisms. Previous studies on multiphase seepage and displacement efficiency have failed to accurately describe the coupled processes of seepage-reaction-dissolution-precipitation, making them unsuitable for characterizing related natural processes and designing underground engineering projects. Therefore, reactive seepage dissolution-precipitation research has become a frontier and hot topic in water conservancy and energy engineering, environmental science and engineering, and hydrogeology.

[0003] A major challenge in the study of reactive seepage dissolution and precipitation lies in the fact that dissolution and precipitation alter the medium's structure, thus affecting the seepage process and solute transport, and consequently disturbing the stress, chemical, temperature, and seepage fields. As crucial parameters of soil and rock media, accurate real-time calculation of porosity and permeability is a prerequisite for understanding the coupled process of seepage-reaction-dissolution and precipitation and for promoting the development of related engineering technologies. However, current methods for determining porosity and permeability in reactive seepage dissolution and precipitation processes suffer from low accuracy and poor timeliness. Therefore, it is necessary to develop a real-time calculation method for porosity and permeability in reactive seepage dissolution and precipitation processes. Summary of the Invention

[0004] The technical problem to be solved by this invention is that current technical methods have low accuracy and poor timeliness in determining porosity and permeability in reactive seepage dissolution and precipitation processes. The purpose of this invention is to provide a method, system, and medium for obtaining parameters of reactive seepage dissolution and precipitation processes. By real-time acquisition of images and real-time pressure monitoring of reactive seepage tests, and based on a pre-constructed precipitation parameter relationship model, real-time calculation of porosity and permeability in reactive seepage dissolution and precipitation processes can be achieved. This invention has the advantages of being easy to operate, having fewer procedures, lower cost, higher accuracy, and better timeliness.

[0005] This invention is achieved through the following technical solution:

[0006] This solution provides a method for obtaining parameters of the reactive seepage dissolution and precipitation process, including:

[0007] Conduct reactive seepage tests and collect image data and seepage pressure data in real time during the reactive seepage test process;

[0008] The image data is preprocessed;

[0009] The changes in sedimentation pixels and the amount of sedimentation during reactive seepage were calculated based on the preprocessed image data.

[0010] The precipitation process parameters are obtained by inputting the changes in the precipitation pixels and the seepage pressure data into the pre-constructed precipitation parameter relationship model.

[0011] The sedimentation process parameters are used to guide the geological sequestration of carbon dioxide.

[0012] A further optimized approach is to conduct a reactive seepage test, including the following methods:

[0013] Using the first and second solutions as fluids, and a combination of porous media and single-fracture structures as the medium structure, reactive seepage tests were conducted; the initial medium permeability and initial medium porosity were recorded.

[0014] The concentrations and flow rates of the first and second solutions are equal.

[0015] A further optimized solution involves real-time acquisition of image data and seepage pressure data during the reactive seepage test; including the following methods:

[0016] Image data of the sedimentation process are acquired at the same frame rate and resolution, while seepage pressure is acquired at the same monitoring frequency and accuracy.

[0017] A further optimization involves preprocessing the image data, including the following methods:

[0018] The preset color attribute value range is used to record the number of original sedimentation data pixels N0 for each image;

[0019] Adjust the color attribute values ​​of each image within the range of color attribute values, and record the number of precipitated data pixels N1 after each adjustment;

[0020] When the difference between the number of pixels N0 in the original sedimentation data and the number of pixels N1 in the sedimentation data is less than 5%, the image under this color attribute value is output.

[0021] A further optimized solution involves calculating the change in sedimentation pixels and the amount of sedimentation during reactive seepage based on the preprocessed image data analysis; including the following method:

[0022] Obtain the pixel change ∆N of the precipitate in each image after preprocessing;

[0023] For porous media, the amount of sediment is calculated by substituting the pixel change ∆N into the following formula:

[0024] ;

[0025] Where ∆M represents the amount of sediment deposited in the porous medium during reactive seepage; ∆N represents the change in the number of pixels occupied by sediment in the image; N T ρ represents the total number of pixels occupied by the flow channel in the image; s represents the flow channel area; h represents the flow channel depth; ρ represents the density of the precipitate.

[0026] For a single-fracture medium, the amount of sediment is calculated by substituting the pixel change ∆N into the following formula:

[0027] ;

[0028] Where L represents the crack length; W represents the crack width; and a represents the average crack aperture.

[0029] A further optimization scheme involves inputting the changes in the sedimentation pixel points and the seepage pressure data into a pre-constructed sedimentation parameter relationship model to obtain the sedimentation process parameters; including the following methods:

[0030] Obtain the change in the number of sedimented pixels at time t;

[0031] The porosity and permeability of the medium are calculated based on the change in the number of precipitated pixels at time t.

[0032] A porosity-permeability relationship diagram was plotted based on the medium porosity and permeability at each time point.

[0033] A further optimization scheme is that the porosity of the medium... Calculate according to the following formula:

[0034] ;

[0035] Where N represents the number of pixels occupied by sediment in the image before seepage; ∆N represents the change in the number of pixels occupied by sediment in the image during seepage; N T This represents the total number of pixels occupied by the flow channels in the image;

[0036] The permeability of the medium is calculated according to the following formula:

[0037] ;

[0038] Where k represents the permeability of the medium; Q represents the flow rate of the fluid; μ represents the viscosity of the fluid; L represents the length of the medium through which the fluid passes; A represents the cross-sectional area of ​​the medium through which the fluid passes; and ∆P represents the pressure difference of the medium through which the fluid passes.

[0039] A further optimization scheme is that the method for drawing the porosity-permeability relationship diagram includes:

[0040] A two-dimensional porosity-permeability relationship diagram was plotted with k / k0 as the first coordinate and φ / φ0 as the second coordinate.

[0041] Where k represents the permeability of the medium; k0 represents the initial permeability of the medium; φ represents the porosity of the medium; and φ0 represents the initial porosity of the medium.

[0042] This solution also provides a parameter acquisition system for the reactive seepage dissolution and precipitation process, used to implement the above-mentioned parameter acquisition method for the reactive seepage dissolution and precipitation process; the system includes:

[0043] The acquisition module is used to conduct reactive seepage tests and acquire image data and seepage pressure data in real time during the reactive seepage test process;

[0044] The preprocessing module is used to preprocess the image data;

[0045] The analysis module is used to analyze and calculate the changes in sedimentation pixels and sedimentation amount during reactive seepage based on the preprocessed image data.

[0046] The calculation module is used to input the changes in the sedimentation pixel points and the seepage pressure data into the pre-constructed sedimentation parameter relationship model to obtain the sedimentation process parameters;

[0047] An application module is used to guide carbon dioxide geological sequestration projects based on the precipitation process parameters.

[0048] This solution also provides a computer-readable medium having a computer program stored thereon, which, when executed by a processor, enables the parameter acquisition method for the reactive percolation dissolution precipitation process described above.

[0049] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0050] 1. The present invention provides a method, system and medium for obtaining parameters of reactive seepage dissolution and precipitation process; by real-time acquisition of images and real-time monitoring of pressure from reactive seepage test, the porosity and permeability of reactive seepage dissolution and precipitation process are calculated in real time based on the established precipitation parameter relationship model, which has the advantages of easy operation, fewer procedures, low cost, high accuracy and good timeliness.

[0051] 2. The present invention provides a method, system, and medium for acquiring parameters of reactive seepage dissolution and precipitation processes; by acquiring image data during the reactive seepage test in real time, the generation, distribution, and morphological changes of precipitates within the pores can be directly observed; by analyzing and calculating the "change in precipitation pixels" from the image data, the precipitation process is transformed from an abstract chemical quantity into an intuitive and quantifiable spatial geometric quantity, greatly improving the directness and accuracy of precipitation measurement; it can capture the dynamic evolution sequence of pore structure and permeability over time, rather than just the initial and final states, which has irreplaceable value for studying the kinetic process of the reaction and identifying critical points (when severe blockage occurs).

[0052] 3. The present invention provides a method, system, and medium for acquiring parameters of a reactive seepage dissolution and precipitation process; it not only uses image data but also simultaneously collects "seepage pressure data." Pressure data reflects the overall ease or difficulty of fluid passing through pore channels (i.e., a macroscopic representation of permeability). The precipitation amount (geometric information) obtained from image analysis and the seepage resistance (kinetic information) obtained from pressure data are jointly input into the "precipitation parameter relationship model," achieving cross-validation and complementarity of information. Attached Figure Description

[0053] To more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be considered as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort. In the drawings:

[0054] Figure 1 A schematic diagram of the parameter acquisition method for reactive seepage dissolution and precipitation process;

[0055] Figure 2 This is a schematic diagram of the dielectric structure;

[0056] Figure 3 This is a schematic diagram of the sedimentation identification results;

[0057] Figure 4 This is a schematic diagram of the porosity evolution curve;

[0058] Figure 5 This is a schematic diagram of the permeability evolution curve;

[0059] Figure 6 This is a schematic diagram illustrating the porosity-permeability relationship.

[0060] Figure 7 A schematic diagram of a parameter acquisition system for a reactive seepage dissolution and precipitation process;

[0061] Figure 8 This is a schematic diagram of the actual data acquisition system. Detailed Implementation

[0062] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0063] Current techniques suffer from low accuracy and poor timeliness in determining porosity and permeability during reactive seepage dissolution and precipitation processes. Therefore, this solution provides the following embodiments to address the aforementioned technical problems:

[0064] Example 1

[0065] This embodiment provides a method for obtaining parameters of a reactive seepage dissolution and precipitation process, such as... Figure 1 As shown, it includes:

[0066] Step 1: Conduct a reactive seepage test and collect image data and seepage pressure data in real time during the reactive seepage test process;

[0067] In step one, the reactive seepage test is carried out, including the following methods:

[0068] Using the first and second solutions as fluids, and a combination of porous media and single-fracture structures as the medium structure, reactive seepage tests were conducted; the initial medium permeability and initial medium porosity were recorded.

[0069] The concentrations and flow rates of the first and second solutions are equal.

[0070] Specifically, in this example, the fluids are determined to be CaCl2 solution and Na2CO3 solution, both with a concentration of 0.10 mol / L and a flow rate of 0.5 μL / min. Figure 2 As shown, the medium structure is a combination of porous medium and single fracture, the channel depth is 0.01 mm, and the initial medium porosity is 0.44.

[0071] The method includes real-time acquisition of image data and seepage pressure data during the reactive seepage test;

[0072] Image data of the sedimentation process are acquired at the same frame rate and resolution, while seepage pressure is acquired at the same monitoring frequency and accuracy.

[0073] Step two involves preprocessing the image data; this step specifically includes the following methods:

[0074] The original image was cropped to a flow channel area of ​​18mm × 6.34mm, and the image was adjusted to fit the flow channel area by moving and rotating it.

[0075] A preset range of color attribute values ​​is defined, and the number of original sedimentation data pixels N0 for each image is recorded. In this embodiment, the color attribute can be grayscale, RGB, or CMYK.

[0076] Adjust the color attribute values ​​of each image within the range of color attribute values, and record the number of precipitated data pixels N1 after each adjustment;

[0077] When the difference between the number of pixels N0 in the original sedimentation data and the number of pixels N1 in the sedimentation data is less than 5%, the image under this color attribute value is output.

[0078] Specifically, in this embodiment, after the first and second solutions are reactively mixed, the precipitates in the image are identified and marked as black using a preset RGB value range. The number of identified precipitate pixels is compared with the number of precipitate pixels in the original (real) image. If the difference is less than 5%, the identification is considered accurate. Using the preset RGB value range, precipitate pixels that conform to the RGB value range will be identified as black. Once all precipitate pixels have been identified, the black areas in the image represent the spatial distribution of the precipitates. The identification result is as follows: Figure 3 As shown.

[0079] Step 3: Based on the preprocessed image data, calculate the change in sedimentation pixels and the amount of sediment during the reactive seepage process; this step specifically includes the following methods:

[0080] Obtain the pixel change ∆N of the precipitate in each image after preprocessing;

[0081] For porous media, the amount of sediment is calculated by substituting the pixel change ∆N into the following formula:

[0082] ;

[0083] Where ∆M represents the amount of sediment (M) in the porous medium during reactive seepage; ∆N represents the change in the number of pixels occupied by sediment in the image; N T The value represents the total number of pixels occupied by the flow channel in the image; s represents the flow channel area (L). 2 h represents the channel depth (L); ρ represents the density of the precipitate (ML). -3 );

[0084] For a single-fracture medium, the amount of sediment is calculated by substituting the pixel change ∆N into the following formula:

[0085] ;

[0086] Where L represents the fracture length (L); W represents the fracture width (L); and a represents the average fracture aperture (L).

[0087] Step four involves inputting the changes in sedimentation pixel values ​​and seepage pressure data into the pre-constructed sedimentation parameter relationship model to obtain sedimentation process parameters. This step specifically includes the following methods:

[0088] Obtain the change in the number of sedimented pixels at time t;

[0089] The porosity and permeability of the medium are calculated based on the change in the number of precipitated pixels at time t.

[0090] A porosity-permeability relationship diagram was plotted based on the medium porosity and permeability at each time point.

[0091] The porosity of the medium Calculate according to the following formula:

[0092] ;

[0093] Where N represents the number of pixels occupied by the sediment in the image before seepage, which is 0 in this embodiment; ∆N represents the change in the number of pixels occupied by the sediment in the image during seepage; N T This represents the total number of pixels occupied by the flow channels in the image;

[0094] The permeability of the medium is calculated according to the following formula:

[0095] ;

[0096] Where k represents the permeability of the medium; Q represents the flow rate of the fluid; μ represents the viscosity of the fluid; L represents the length of the medium through which the fluid passes; A represents the cross-sectional area of ​​the medium through which the fluid passes; and ∆P represents the pressure difference of the medium through which the fluid passes.

[0097] The dissolution rate and precipitation rate R of the reactive seepage process can be calculated and analyzed based on the calculated amount of dissolution or precipitation. The calculation formula is as follows:

[0098] ;

[0099] In the formula, R is the dissolution rate or precipitation rate; ∆M is the amount of solution or precipitation during the reactive seepage process; and ∆t is the dissolution or precipitation time.

[0100] Based on the precipitation parameter relationship model, multiple sets of porosity and permeability were obtained, and the porosity evolution curves and permeability evolution curves were plotted as follows: Figure 4 and Figure 5 As shown;

[0101] The method for drawing the porosity-permeability relationship diagram includes:

[0102] A two-dimensional porosity-permeability relationship diagram was plotted with k / k0 as the first coordinate and φ / φ0 as the second coordinate.

[0103] Where k represents the permeability of the medium; k0 represents the initial permeability of the medium; φ represents the porosity of the medium; and φ0 represents the initial porosity of the medium.

[0104] The porosity-permeability relationship diagram drawn in this embodiment is as follows: Figure 6 As shown.

[0105] Step 6: Guide the carbon dioxide geological sequestration project based on the precipitation process parameters.

[0106] This invention proposes a real-time calculation method for porosity and permeability during reactive seepage dissolution and precipitation processes. This method enables real-time calculation of the porosity and permeability of media under the influence of reactive seepage dissolution and precipitation, and can be used to characterize the porosity and permeability of porous fractured media near the wellbore in carbon dioxide geological storage projects, thereby serving the optimization of carbon dioxide geological storage project implementation measures.

[0107] Example 2

[0108] This embodiment provides a parameter acquisition system for a reactive seepage dissolution and precipitation process, used to implement the parameter acquisition method for the reactive seepage dissolution and precipitation process described in Example 1; such as Figure 7 As shown, the system includes:

[0109] The data acquisition module is used to conduct reactive seepage tests and acquire image data and seepage pressure data in real time during the reactive seepage test process; such as... Figure 8 As shown, the acquisition module mainly includes a light source, a camera, a pressure sensor, and a syringe pump; the camera acquires image data during the reactive seepage test; and the pressure sensor acquires seepage pressure data during the reactive seepage test.

[0110] The preprocessing module is used to preprocess the image data;

[0111] The analysis module is used to analyze and calculate the changes in sedimentation pixels and sedimentation amount during reactive seepage based on the preprocessed image data.

[0112] The calculation module is used to input the changes in the sedimentation pixel points and the seepage pressure data into the pre-constructed sedimentation parameter relationship model to obtain the sedimentation process parameters;

[0113] An application module is used to guide carbon dioxide geological sequestration projects based on the precipitation process parameters.

[0114] Example 3

[0115] This embodiment provides a computer-readable medium having a computer program stored thereon. The computer program, when executed by a processor, can implement the parameter acquisition method for the reactive percolation dissolution and precipitation process as described in Example 1; specifically, it performs the following steps:

[0116] Step 1: Conduct a reactive seepage test and collect image data and seepage pressure data in real time during the reactive seepage test process;

[0117] Step two: Preprocess the image data;

[0118] Step 3: Analyze and calculate the change in sedimentation pixels and the amount of sedimentation during the reactive seepage process based on the preprocessed image data.

[0119] Step 4: Input the changes in the sedimentation pixel points and the seepage pressure data into the pre-constructed sedimentation parameter relationship model to obtain the sedimentation process parameters;

[0120] Step 5: Guide the carbon dioxide geological sequestration project based on the precipitation process parameters.

[0121] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for obtaining parameters of a reactive seepage dissolution and precipitation process, characterized in that, include: Conduct reactive seepage tests and collect image data and seepage pressure data in real time during the reactive seepage test process; The image data is preprocessed; The changes in sedimentation pixels and the amount of sedimentation during reactive seepage were calculated based on the preprocessed image data. The precipitation process parameters are obtained by inputting the changes in the precipitation pixels and the seepage pressure data into the pre-constructed precipitation parameter relationship model. The sedimentation process parameters are used to guide the geological sequestration of carbon dioxide.

2. The method for obtaining parameters of the reactive percolation dissolution and precipitation process according to claim 1, characterized in that, The reactive seepage test was carried out; Including methods: Reactive seepage tests were conducted using the first and second solutions as fluids and a combination of porous media and single-crack structures as the media structure. Record the initial permeability and initial porosity of the medium structure; The concentrations and flow rates of the first and second solutions are equal.

3. The method for obtaining parameters of the reactive percolation dissolution and precipitation process according to claim 1, characterized in that, The method includes real-time acquisition of image data and seepage pressure data during the reactive seepage test; Image data of the sedimentation process are acquired at the same frame rate and resolution, while seepage pressure is acquired at the same monitoring frequency and accuracy.

4. The method for obtaining parameters of the reactive percolation dissolution and precipitation process according to claim 2, characterized in that, The image data is preprocessed; Including methods: The preset color attribute value range is used to record the number of original sedimentation data pixels N0 for each image; Adjust the color attribute values ​​of each image within the range of color attribute values, and record the number of precipitated data pixels N1 after each adjustment; When the difference between the number of pixels N0 in the original sedimentation data and the number of pixels N1 in the sedimentation data is less than 5%, the image under this color attribute value is output.

5. The method for obtaining parameters of the reactive percolation dissolution and precipitation process according to claim 4, characterized in that, The changes in sedimentation pixels and the amount of sedimentation during reactive seepage are calculated based on the preprocessed image data. Including methods: Obtain the pixel change ∆N of the precipitate in each image after preprocessing; For porous media, the amount of sediment is calculated by substituting the pixel change ∆N into the following formula: ； Where ∆M represents the amount of sediment deposited in the porous medium during reactive seepage; ∆N represents the change in the number of pixels occupied by sediment in the image; N T ρ represents the total number of pixels occupied by the flow channel in the image; s represents the flow channel area; h represents the flow channel depth; ρ represents the density of the precipitate. For a single-fracture medium, the amount of sediment is calculated by substituting the pixel change ∆N into the following formula: ； Where L represents the crack length; W represents the crack width; and a represents the average crack aperture.

6. The method for obtaining parameters of the reactive percolation dissolution and precipitation process according to claim 1, characterized in that, The sedimentation process parameters are obtained by inputting the changes in sedimentation pixel points and seepage pressure data into a pre-constructed sedimentation parameter relationship model; including the following methods: Obtain the change in the number of sedimented pixels at time t; The porosity and permeability of the medium are calculated based on the change in the number of precipitated pixels at time t. A porosity-permeability relationship diagram was plotted based on the medium porosity and permeability at each time point.

7. The method for obtaining parameters of the reactive percolation dissolution and precipitation process according to claim 6, characterized in that, The porosity of the medium Calculate according to the following formula: ； Where N represents the number of pixels occupied by sediment in the image before seepage; ∆N represents the change in the number of pixels occupied by sediment in the image during seepage; N T This represents the total number of pixels occupied by the flow channels in the image; The permeability of the medium is calculated according to the following formula: ； Where k represents the permeability of the medium; Q represents the flow rate of the fluid; μ represents the viscosity of the fluid; L represents the length of the medium through which the fluid passes; A represents the cross-sectional area of ​​the medium through which the fluid passes; and ∆P represents the pressure difference of the medium through which the fluid passes.

8. The method for obtaining parameters of the reactive percolation dissolution and precipitation process according to claim 6, characterized in that, The method for drawing the porosity-permeability relationship diagram includes: A two-dimensional porosity-permeability relationship diagram was plotted with k / k0 as the first coordinate and φ / φ0 as the second coordinate. Where k represents the permeability of the medium; k0 represents the initial permeability of the medium; φ represents the porosity of the medium; and φ0 represents the initial porosity of the medium.

9. A parameter acquisition system for a reactive percolation dissolution and precipitation process, characterized in that, A method for obtaining parameters for implementing the reactive percolation dissolution and precipitation process according to any one of claims 1-8; the system comprises: The acquisition module is used to conduct reactive seepage tests and acquire image data and seepage pressure data in real time during the reactive seepage test process; The preprocessing module is used to preprocess the image data; The analysis module is used to analyze and calculate the changes in sedimentation pixels and sedimentation amount during reactive seepage based on the preprocessed image data. The calculation module is used to input the changes in the sedimentation pixel points and the seepage pressure data into the pre-constructed sedimentation parameter relationship model to obtain the sedimentation process parameters; An application module is used to guide carbon dioxide geological sequestration projects based on the precipitation process parameters.

10. A computer-readable medium having a computer program stored thereon, characterized in that, The computer program, when executed by a processor, can implement the parameter acquisition method for the reactive percolation dissolution precipitation process as described in any one of claims 1-8.

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