Method and device for predicting migration range of carbon dioxide in saline water layer and computer equipment

Abstract

The invention provides a salt water layer carbon dioxide migration range prediction method and device and computer equipment, and relates to the technical field of carbon dioxide geological storage. The method comprises the following steps: simulating a carbon dioxide injection process by using a numerical simulation model; calculating carbon dioxide density distribution by utilizing formation pressure data of the sequestration area; according to the gravity abnormal data of the storage region, the carbon dioxide density distribution and the migration range of the carbon dioxide in the tectonic trap region, determining the proportion of the mass variation, caused by pore constraint, of the carbon dioxide in the migration range of the tectonic trap region in the total mass variation of the carbon dioxide in the migration range of the tectonic trap region; determining the proportion as a first coefficient; and calculating the actual carbon dioxide overflow regional area according to the first coefficient. According to the method, the gravity abnormal data and the ground pressure monitoring data are combined for joint inversion, and low-cost, high-efficiency and high-precision prediction of the carbon dioxide migration range is achieved.

Description

Technical Field

[0001] This application belongs to the field of geological carbon dioxide sequestration and utilization, specifically relating to a method for predicting the migration range of carbon dioxide in saline aquifers, a device for predicting the migration range of carbon dioxide in saline aquifers, a computer device, and a machine-readable storage medium. Background Technology

[0002] Monitoring carbon dioxide (COD) storage sites is a crucial step in achieving large-scale, safe, and effective geological COD storage. Monitoring of COD geological storage involves continuous / intermittent monitoring during the COD injection phase, as well as long-term monitoring after injection cessation to ensure storage safety. Geophysical monitoring is the primary method, utilizing time-delayed geophysical methods, which involve dynamic monitoring of the COD storage process through repeated geophysical observations. Geophysical methods primarily employ seismic methods, including 3D seismic, inter-well seismic, downhole seismic, and microseismic methods. Other monitoring methods include satellite remote sensing, time-delayed geomagnetism, and time-delayed gravity. Most geophysical monitoring methods are costly and susceptible to limitations imposed by measurement conditions. Gravity methods measure abnormal changes in gravity based on the non-uniformity of mass distribution of rock and fluid media in the formation after COD injection. Gravity detection is conducted at different stages of COD geological storage projects, and the obtained time-delayed gravity data can be used to infer the migration of COD in the formation based on changes in gravity anomalies. Time-delayed gravity measurement is more economical than geophysical monitoring methods such as seismic surveys. It does not rely on sensors within monitoring or injection wells and can be performed on the surface using gravity measuring instruments, offering advantages in flexibility and mobility, depending on the monitoring network at different engineering stages. Currently, time-delayed gravity measurement has been applied in oil and gas reservoirs and saline water layer carbon dioxide geological sequestration projects, including the Sleipner project in Norway, the Gundih pilot project in Indonesia, the CarbonSAFE project in North Dakota, the SECARB Cranfield project in Mississippi, and the Kevin Dome project in Montana. Studies have been completed on the impact of gravity data background values ​​and the adaptability of gravity detection methods in different reservoirs. Furthermore, by combining seismic data, the inversion of carbon dioxide sequestration volume and carbon dioxide migration paths has been achieved. However, the gravity anomalies caused by carbon dioxide injection operations are related to many factors such as carbon dioxide saturation, carbon dioxide density, brine density, rock density, storage unit volume and porosity. Existing studies cannot complete the inversion of the carbon dioxide migration range solely through gravity anomaly data. Therefore, it is urgent to study methods to predict the carbon dioxide migration range through gravity data in order to identify potential leakage risks and promote the development of carbon dioxide geological storage monitoring technology. Summary of the Invention

[0003] The purpose of this application is to provide a method, a device, a computer device, and a machine-readable storage medium for predicting the range of carbon dioxide migration in saline aquifers, in order to overcome the shortcomings of existing technologies, such as the high cost of carbon dioxide migration prediction based on geophysical monitoring methods, and the difficulty of inversion in predicting carbon dioxide migration solely based on gravity anomaly data due to the many influencing factors in the interpretation of gravity anomaly data.

[0004] To achieve the above objectives, a first aspect of this application provides a method for predicting the range of carbon dioxide transport in a saline aquifer, comprising: A numerical simulation model for carbon dioxide sequestration in a saline aquifer is constructed. The carbon dioxide sequestration area obtained through geological modeling in the numerical simulation model includes tectonic trap areas and potential overflow areas. The carbon dioxide injection process was simulated using the numerical simulation model to obtain the first extension thickness and the migration range of carbon dioxide in the structural trap area. The first extension thickness is the extension thickness of carbon dioxide reaching the potential overflow area in the direction parallel to the well depth of the carbon dioxide injection well. The carbon dioxide density distribution in the sealed area was calculated using the formation pressure data of the sealed area. Based on the gravity anomaly data of the sealed area, the carbon dioxide density distribution, and the migration range of carbon dioxide in the structural trap area, the proportion of the mass change caused by carbon dioxide being bound by pores in the migration range of the structural trap area is determined to be the proportion of the total mass change in the migration range of the structural trap area, and the proportion is determined as the first coefficient. The actual area of ​​carbon dioxide overflow is calculated based on the first coefficient, the solubility of carbon dioxide in formation water, and the density distribution of carbon dioxide, so as to obtain the range of carbon dioxide migration in the potential overflow area.

[0005] In a specific embodiment of this application, the step of determining the proportion of the mass change caused by carbon dioxide being bound by pores within the migration range of the structural trap, based on gravity anomaly data of the sealed area, carbon dioxide density distribution, and the migration range of carbon dioxide within the structural trap, in the total mass change within the migration range of the structural trap, and then determining the proportion as a first coefficient, includes: Calculate the fluid density change at different locations in the sealed area based on the gravity anomaly data of the sealed area; Calculate the total mass change within the transport range of the structural trap region based on the fluid density change; The porosity, bound gas saturation, and formation water density of the sealed area were obtained. The mass change caused by carbon dioxide being bound by pores within the migration range of the structural trap area is calculated based on the porosity, bound gas saturation, formation water density, and carbon dioxide density distribution of the sealed area. The ratio of the total mass change within the migration range of the tectonic trap to the mass change caused by carbon dioxide being confined by pores within the migration range of the tectonic trap is calculated, and this ratio is used as the first coefficient.

[0006] In a specific embodiment of this application, calculating the total mass change within the transport range of the constructed trap region based on the fluid density change includes: Calculate the average fluid density change at different locations within the migration range of the structural trap within the sealed area to obtain the average fluid density change within the migration range of the structural trap. ; Total volume of geological grid for calculating the migration range of tectonic traps ; Calculate the total mass change within the transport range of the constructed trap region. .

[0007] In a specific embodiment of this application, the calculation of the mass change caused by carbon dioxide being bound by pores within the migration range of the structural trap area based on the porosity, bound gas saturation, formation water density, and carbon dioxide density distribution of the sealed area includes: Calculate the mass change caused by carbon dioxide being bound by pores within the transport range of a structurally confined region. ; in, This indicates the porosity of the sealed area; This indicates the saturation of the binding gas in the sealed area; Indicates the migration range of the tectonic trap region. Total number of geological grids in the direction, express Numbering of directional geological grids; Indicates the migration range of the tectonic trap region. Total number of geological grids in the direction, express Numbering of directional geological grids; Indicates the migration range of the tectonic trap region. Total number of geological grids in the direction, express Numbering of directional geological grids; Indicates coordinates as The volume of the geological grid; This indicates the density of formation water in the sealed area; Indicates coordinates as Carbon dioxide density at the geological grid.

[0008] In a specific embodiment of this application, calculating the area of ​​the actual carbon dioxide overflow region based on the first coefficient, the solubility of carbon dioxide in formation water, and the carbon dioxide density distribution includes: The total amount of carbon dioxide stored within the migration range of the tectonic trap area is calculated based on the first coefficient, the solubility of carbon dioxide in formation water, and the density distribution of carbon dioxide. The residual gaseous carbon dioxide in the potential overflow zone is calculated based on the total carbon dioxide injection, the total amount of carbon dioxide stored within the migration range of the structural trap, the carbon dioxide density distribution, and the first coefficient. The actual area of ​​carbon dioxide overflow is calculated based on the residual gaseous content of carbon dioxide in the potential overflow zone, the first extension thickness, and the first coefficient.

[0009] In a specific embodiment of this application, the calculation of the total amount of carbon dioxide within the migration range of the structural trap area based on the first coefficient, the solubility of carbon dioxide in formation water, and the density distribution of carbon dioxide includes: Calculate the sum of the tectonic and residual gaseous carbon dioxide reserves within the migration range of the tectonic trap region. ; Calculate the amount of formation water within the migration range of the tectonic trap area. ; Calculate the amount of dissolved state within the migration range of the constructed trap region. ; The sum of the tectonic occurrence, residual gaseous occurrence, and dissolved occurrence of carbon dioxide within the migration range of the tectonic trap is calculated, and the sum is taken as the total occurrence of carbon dioxide within the migration range of the tectonic trap. in, The total volume of the geological grid representing the migration range of the tectonic trap area; This indicates the porosity of the sealed area; This indicates the saturation of the binding gas in the sealed area; Indicates the first coefficient; This refers to the average carbon dioxide density of the tectonic trap area, obtained by averaging the carbon dioxide density of each geological grid within the migration range of the tectonic trap area using the aforementioned carbon dioxide density distribution. This indicates the density of formation water in the sealed area; This indicates the solubility of carbon dioxide in formation water; This indicates the amount of residual gaseous matter within the migration range of the structural trap region; This indicates the amount of tectonic deposits within the migration range of a tectonic trap region.

[0010] In a specific embodiment of this application, the calculation of the residual gaseous carbon dioxide in the potential overflow zone based on the total carbon dioxide injection volume, the total amount of carbon dioxide stored within the migration range of the structural trap area, the carbon dioxide density distribution, and a first coefficient includes: The difference between the total amount of carbon dioxide injected and the total amount of carbon dioxide stored within the migration range of the structural trap area is taken as the amount of carbon dioxide entering the potential overflow area. Calculate the residual gaseous quantity of carbon dioxide in the potential overflow zone. ; in, This indicates the amount of carbon dioxide entering the potential overflow area; This represents the average carbon dioxide density of the potential overflow area, obtained by taking the mean value of the carbon dioxide density of each geological grid within the potential overflow area using the aforementioned carbon dioxide density distribution. This indicates the saturation of the binding gas in the sealed area; Indicates the first coefficient; This indicates the density of formation water in the sealed area; This indicates the solubility of carbon dioxide in formation water.

[0011] In a specific embodiment of this application, the following formula is used when calculating the area of ​​the actual carbon dioxide overflow region based on the residual gaseous content of carbon dioxide in the potential overflow zone, the first extension thickness, and the first coefficient: ; in, This represents the area of ​​the actual carbon dioxide overflow. Indicates the first extended thickness; This indicates the amount of residual gaseous carbon dioxide in the potential overflow area; This represents the average carbon dioxide density of the potential overflow area, obtained by taking the mean value of the carbon dioxide density of each geological grid within the potential overflow area using the aforementioned carbon dioxide density distribution. This indicates the porosity of the sealed area; This indicates the saturation of the binding gas in the sealed area; This represents the first coefficient.

[0012] In a specific embodiment of this application, the numerical simulation model for constructing a saline aquifer for carbon dioxide sequestration includes a carbon dioxide sequestration area obtained through geological modeling, comprising a tectonic trap zone and a potential overflow zone, including: Obtain the formation physical properties and fluid physical properties of the carbon dioxide storage area; The geological properties of the carbon dioxide sequestration area are used as the geological attributes of each volume element in the geological model to construct a geological model of the carbon dioxide sequestration area. The carbon dioxide sequestration area in the geological model includes structural trap areas and potential overflow areas. By inputting the fluid properties of the carbon dioxide sequestration area and the pre-constructed fluid transport control equations into the geological model, a numerical simulation model of carbon dioxide sequestration in a saline aquifer is obtained.

[0013] In a specific embodiment of this application, the numerical simulation model is used to simulate the carbon dioxide injection process to obtain a first extension thickness and the migration range of carbon dioxide in the structural trap zone. The first extension thickness is the extension thickness of carbon dioxide reaching the potential overflow zone in the direction parallel to the well depth of the carbon dioxide injection well, including: The pressure-driven process during carbon dioxide injection and the gravity-driven process after injection is stopped are simulated using the numerical simulation model to obtain the first expansion thickness, which is the expansion thickness of carbon dioxide reaching the potential overflow zone in the direction parallel to the depth of the carbon dioxide injection well. The migration thickness of carbon dioxide in the structural trap is calculated based on the structural undulation parameters of the geological model of the carbon dioxide storage area obtained by geological modeling in the numerical simulation model and the first extended thickness. The direction of this thickness is parallel to the well depth direction of the carbon dioxide injection well. The migration area of ​​carbon dioxide in the tectonic trap area is calculated based on the tectonic undulation parameters of the geological model. The migration range of carbon dioxide in the structural trap can be obtained by measuring the migration thickness and area of ​​carbon dioxide in the structural trap.

[0014] In a specific embodiment of this application, the method further includes: Combining the distribution of gravity monitoring points and the distribution of gravity anomaly points within the sealed area determined by gravity anomaly data, the migration range of carbon dioxide in the constructed trap area and the migration range of carbon dioxide in the potential overflow area are plotted to obtain a rectangular migration range. The rectangular migration range is modified by utilizing the geological characteristics of the sealed area, including the source direction, sand body distribution characteristics, and fault distribution.

[0015] A second aspect of this application provides a device for predicting the range of carbon dioxide transport in a saline aquifer, comprising: The modeling module is used to construct a numerical simulation model for carbon dioxide sequestration in saline aquifers. The carbon dioxide sequestration area obtained through geological modeling in the numerical simulation model includes tectonic trap areas and potential overflow areas. The simulation module is used to simulate the carbon dioxide injection process using the numerical simulation model to obtain the first extension thickness and the migration range of carbon dioxide in the constructed trap area. The first extension thickness is the extension thickness of carbon dioxide reaching the potential overflow area in the direction parallel to the well depth of the carbon dioxide injection well. The density distribution calculation module is used to calculate the carbon dioxide density distribution of the storage area using the formation pressure data of the storage area. The first coefficient determination module is used to determine the proportion of the mass change caused by carbon dioxide being bound by pores within the transport range of the structural trap area to the total mass change within the transport range of the structural trap area based on the gravity anomaly data of the sealed area, the carbon dioxide density distribution, and the transport range of carbon dioxide within the structural trap area, and to determine the proportion as the first coefficient. The migration range determination module is used to calculate the actual overflow area of ​​carbon dioxide based on the first coefficient, the solubility of carbon dioxide in formation water, and the density distribution of carbon dioxide, so as to obtain the migration range of carbon dioxide in the potential overflow area.

[0016] In a specific embodiment of this application, the step of determining the proportion of the mass change caused by carbon dioxide being bound by pores within the migration range of the structural trap, based on gravity anomaly data of the sealed area, carbon dioxide density distribution, and the migration range of carbon dioxide within the structural trap, in the total mass change within the migration range of the structural trap, and then determining the proportion as a first coefficient, includes: Calculate the fluid density change at different locations in the sealed area based on the gravity anomaly data of the sealed area; Calculate the total mass change within the transport range of the structural trap region based on the fluid density change; The porosity, bound gas saturation, and formation water density of the sealed area were obtained. The mass change caused by carbon dioxide being bound by pores within the migration range of the structural trap area is calculated based on the porosity, bound gas saturation, formation water density, and carbon dioxide density distribution of the sealed area. The ratio of the total mass change within the migration range of the tectonic trap to the mass change caused by carbon dioxide being confined by pores within the migration range of the tectonic trap is calculated, and this ratio is used as the first coefficient.

[0017] A third aspect of this application provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the method for predicting the range of carbon dioxide transport in saline aquifers as described in the first aspect of this application.

[0018] The fourth aspect of this application provides a machine-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method for predicting the range of carbon dioxide transport in saline aquifers as described in the first aspect of this application.

[0019] In the above technical solution, after obtaining the first extended thickness through numerical simulation, analytical solutions are performed using gravity anomaly data and formation pressure data. The analytical solution process for determining the migration range of carbon dioxide in the potential overflow zone is defined by considering the proportion of the mass change caused by pore confinement within the structural trap migration range in the total mass change within the structural trap migration range. Compared to carbon dioxide migration monitoring that relies on geophysical monitoring methods, the entire carbon dioxide migration range prediction process does not depend on geophysical monitoring methods; carbon dioxide migration prediction is achieved through gravity monitoring and formation pressure monitoring, thus reducing costs. In existing technologies, inversion using only gravity monitoring data can only obtain a rough carbon dioxide migration range with low prediction accuracy. In the above technical solution, the inversion during numerical simulation using gravity anomaly data and formation pressure data improves the prediction accuracy of the carbon dioxide migration range. Simultaneously, the entire prediction process does not involve complex displacement flow process simulations. Compared to the computational complexity of displacement flow process simulations, the computational complexity of the defined analytical solution process is significantly reduced, thereby improving the prediction efficiency of the migration range.

[0020] In summary, the above technical solutions comprehensively consider prediction cost, prediction accuracy, and prediction efficiency, and the methods are easy to apply and highly feasible.

[0021] Other features and advantages of the embodiments of this application will be described in detail in the following detailed description section. Attached Figure Description

[0022] The accompanying drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the following detailed description to explain the embodiments of this application, but do not constitute a limitation on the embodiments of this application. In the drawings: Figure 1 This schematically illustrates a first flowchart of a method for predicting the range of carbon dioxide transport in saline aquifers according to an embodiment of this application; Figure 2 A second flowchart illustrating a method for predicting the range of carbon dioxide transport in saline aquifers according to an embodiment of this application is shown schematically. Figure 3 This schematically illustrates a technical roadmap for a method for predicting the range of carbon dioxide transport in saline aquifers according to embodiments of this application. Figure 4 A schematic diagram of a geological model of a carbon dioxide storage area according to an embodiment of this application is shown. Figure 5 The schematic diagram illustrates a simplified vertical cross-sectional view of the constructed enclosed area and potential overflow area according to an embodiment of this application; Figure 6 This schematic diagram illustrates the arrangement of gravity measurement points according to an embodiment of this application. Figure 7 A schematic diagram illustrating a rectangular concept of a carbon dioxide transport range according to an embodiment of this application is shown. Figure 8 A schematic diagram illustrating the planar distribution of carbon dioxide transport range according to an embodiment of this application is shown. Figure 9 This schematic diagram illustrates the composition of a saline aquifer carbon dioxide transport range prediction device according to an embodiment of the present application. Figure 10 A schematic block diagram of a computer device according to an embodiment of this application is shown. Detailed Implementation

[0023] The specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the embodiments of this application.

[0024] If the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0025] Figure 1 A schematic flowchart illustrates a first method for predicting the range of carbon dioxide transport in saline aquifers according to an embodiment of this application. Figure 1 As shown in the figure, this application provides a method for predicting the range of carbon dioxide transport in a saline aquifer, which may include the following steps: Step 100: Construct a numerical simulation model for carbon dioxide sequestration in a saline aquifer. The carbon dioxide sequestration area obtained through geological modeling in the numerical simulation model includes tectonic trap areas and potential overflow areas.

[0026] In this application, the potential overflow zone refers to the area where a potential overflow path is located within the confined structure of the carbon dioxide storage area. Preferably, in a specific embodiment, the potential overflow zone is a certain area extending beyond the potential overflow path. The degree of extension can be differentiated according to the specific storage area, thereby avoiding the impact of errors in determining the potential overflow path on the prediction of the entire carbon dioxide migration range.

[0027] Step 102: Simulate the carbon dioxide injection process using a numerical simulation model to obtain the first extension thickness and the migration range of carbon dioxide in the structural trap area. The first extension thickness is the extension thickness of carbon dioxide reaching the potential overflow area in the direction parallel to the well depth of the carbon dioxide injection well.

[0028] In this application, the carbon dioxide injection process includes a pressure-driven process during carbon dioxide injection and a gravity-driven process after injection stops. When the carbon dioxide injection well is a vertical well, the first extension thickness is also referred to as the vertical thickness of carbon dioxide overflowing into the potential overflow zone.

[0029] Step 104: Calculate the carbon dioxide density distribution in the storage area using the formation pressure data of the storage area.

[0030] Step 106: Based on the gravity anomaly data of the sealed area, the carbon dioxide density distribution, and the migration range of carbon dioxide in the structural trap area, determine the proportion of the mass change caused by carbon dioxide being bound by pores within the migration range of the structural trap area in the total mass change within the migration range of the structural trap area, and determine this proportion as the first coefficient.

[0031] In this application, gravity anomaly data includes gravity anomaly values ​​at various points within the storage area where gravity anomalies occur, obtained from gravity monitoring data. It is known that, according to the law of universal gravitation, the change in fluid density can be calculated from gravity anomaly data. Given the known spatial volume defined by the migration range within the structural trap, the total mass change within the migration range of the structural trap can be calculated by combining the fluid density change. Knowing the saturation of bound carbon dioxide in the porous medium under saline aquifer conditions, the mass change caused by carbon dioxide being bound by pores within the migration range of the structural trap can be calculated based on the pore volume of residual carbon dioxide gas within the migration range of the structural trap, the carbon dioxide density distribution within the storage area, and the formation water density.

[0032] Step 108: Calculate the actual area of ​​carbon dioxide overflow based on the first coefficient, the solubility of carbon dioxide in formation water, and the density distribution of carbon dioxide.

[0033] In this application, the solubility of carbon dioxide in formation water can be obtained through calculation or measurement. It should be understood that after obtaining the vertical thickness of carbon dioxide overflowing into the potential overflow zone in step 102, to determine the actual overflow area of ​​carbon dioxide, the technical concept of designing a first coefficient in step 106 allows for the inversion of the actual overflow area of ​​carbon dioxide using the first coefficient and the residual gaseous quantity of carbon dioxide in the potential overflow zone (residual quantity). The residual gaseous quantity of carbon dioxide in the potential overflow zone can be calculated using the total amount of carbon dioxide injected after calculating the total quantity within the migration range of a known volume of structural trap. The total quantity within the migration range of a known volume of structural trap needs to be determined in conjunction with the solubility of carbon dioxide in formation water and the carbon dioxide density distribution.

[0034] In one specific embodiment, calculating the solubility of carbon dioxide in formation water includes the following steps: Acquire formation pressure and formation temperature data for the storage area; Calculate the average pressure of each geological grid within the migration range of the tectonic trap area; Calculate the average temperature of each geological grid within the migration range of the tectonic trap area; The solubility of carbon dioxide in the formation water was calculated based on the formation water properties of the sealed area, the average pressure of each geological grid, and the average temperature of each geological grid.

[0035] For example, by monitoring the surface pressure and surface temperature of the sealed area, surface pressure data and surface temperature data of the sealed area can be collected. Then, based on the geothermal gradient and geopressure gradient, the temperature and pressure of different geological grids in the geological model can be calculated.

[0036] Step 110: Based on the calculated area of ​​the actual carbon dioxide overflow and the first extended thickness, obtain the migration range of carbon dioxide in the potential overflow zone.

[0037] As in the above embodiment, the carbon dioxide injection process is first simulated using a numerical simulation model to obtain the first extension thickness. Then, a first coefficient is defined, and an analytical solution method for inverting the migration range of carbon dioxide in the potential overflow zone is constructed using the first coefficient. The entire analytical solution process abandons the numerical simulation of the displacement flow process in the prior art. The analytical solution process combines gravity anomaly data and formation pressure data, thereby making the accuracy of the predicted migration range better than the migration prediction results obtained solely through gravity monitoring data. Furthermore, the prediction cost is significantly lower than the cost of migration prediction schemes relying on geophysical monitoring methods, and the prediction efficiency is high. It is evident that the above embodiment has strong operability.

[0038] In one specific embodiment of this application, the gravity anomaly data is surface gravity anomaly data. Surface gravity detection devices are portable and have short measurement times, allowing for real-time adjustments to monitoring schemes based on project needs. Analyzing surface gravity detection data makes the acquisition of basic data for predicting carbon dioxide migration ranges more flexible and cost-effective. This enables the prediction of carbon dioxide migration ranges throughout the entire lifecycle of a saline aquifer carbon dioxide sequestration project, thereby improving prediction efficiency, reducing prediction costs, and enhancing the operability of the prediction process.

[0039] In one specific embodiment of this application, step 100 involves constructing a numerical simulation model for carbon dioxide sequestration in a saline aquifer. The carbon dioxide sequestration area obtained through geological modeling in the numerical simulation model includes tectonic trap areas and potential overflow areas, and may include the following steps: A numerical simulation model for carbon dioxide sequestration in saline aquifers was constructed. The carbon dioxide sequestration areas obtained through geological modeling in the numerical simulation model include tectonic traps and potential overflow zones, including: Obtain the formation physical properties and fluid physical properties of the carbon dioxide storage area; The geological properties of the carbon dioxide sequestration area are used as the geological attributes of each volume element in the geological model to construct a geological model of the carbon dioxide sequestration area. The carbon dioxide sequestration area in the geological model includes the tectonic trap area and the potential overflow area. By inputting the fluid properties of the carbon dioxide sequestration area and the pre-constructed fluid transport control equations into the geological model, a numerical simulation model of carbon dioxide sequestration in a saline aquifer is obtained.

[0040] As in the above embodiment, the data simulation model is constrained by formation physical parameters and fluid physical parameters, which improves the accuracy of the data simulation model and thus improves the accuracy of carbon dioxide migration range prediction.

[0041] In one specific embodiment of this application, step 102, simulating the carbon dioxide injection process using a numerical simulation model to obtain the first extension thickness and the migration range of carbon dioxide in the constructed trap area, wherein the first extension thickness is the extension thickness of carbon dioxide reaching the potential overflow area in the direction parallel to the well depth of the carbon dioxide injection well, may include the following steps: The pressure-driven process during carbon dioxide injection and the gravity-driven process after injection stops were simulated using a numerical simulation model to obtain the first expansion thickness, which is the expansion thickness of carbon dioxide reaching the potential overflow zone in the direction parallel to the depth of the carbon dioxide injection well. The migration thickness of carbon dioxide in the structural trap is calculated based on the structural undulation parameters and the first extended thickness of the geological model of the carbon dioxide storage area obtained through geological modeling in the numerical simulation model. The direction of this thickness is parallel to the well depth direction of the carbon dioxide injection well. The migration area of ​​carbon dioxide in the tectonic trap is calculated based on the tectonic undulation parameters of the geological model. The migration range of carbon dioxide in the structural trap can be obtained by measuring the migration thickness and area of ​​carbon dioxide in the structural trap.

[0042] In one specific embodiment of this application, step 106, determining the proportion of the mass change caused by carbon dioxide being bound by pores within the structural trap range to the total mass change within the structural trap range based on gravity anomaly data of the sealed area, carbon dioxide density distribution, and the migration range of carbon dioxide within the structural trap range, and determining this proportion as a first coefficient, includes the following steps: Calculate the fluid density change at different locations within the sealed area based on gravity anomaly data of the sealed area; Calculate the total mass change within the transport range of the structural trap based on the change in fluid density. Obtain the porosity, bound gas saturation, and formation water density of the sealed area; The mass change caused by carbon dioxide being bound by pores in the structural trap area is calculated based on the porosity, bound gas saturation, formation water density and carbon dioxide density distribution of the sealed area. The ratio of the total mass change within the migration range of the structural trap to the mass change caused by carbon dioxide being bound by pores within the structural trap is calculated, and this ratio is used as the first coefficient.

[0043] For example, laboratory experiments can be conducted on core samples from the sealed area in advance to measure the porosity and permeability of the core samples. After saturating the core samples with formation water, high-temperature and high-pressure core displacement experiments can be carried out to obtain the relative permeability curves of carbon dioxide and formation water. Based on the relative permeability curves, the bound gas saturation of carbon dioxide in saturated formation water can be determined. This bound gas saturation is considered to be the bound gas saturation of carbon dioxide in the porous medium under saline aquifer conditions, and it represents the minimum carbon dioxide saturation within the carbon dioxide migration range. To obtain the formation water density, formation water samples from the sealed area can be collected and analyzed to obtain the salinity, salt ion composition, and density of the water samples.

[0044] For example, calculating the total mass change within the transport range of the constructed trap region based on the fluid density change may include the following steps: The mean value of the fluid density change at different locations within the migration range of the tectonic trap within the sealed area is calculated to obtain the average fluid density change within the migration range of the tectonic trap. ; Total volume of geological grid for calculating the migration range of tectonic traps ; Calculate the total mass change within the transport range of the constructed trap region. (Formula 1).

[0045] For example, calculating the mass change of carbon dioxide caused by its binding within the pores of a structural trap based on the porosity, bound gas saturation, formation water density, and carbon dioxide density distribution of the sealed area may include the following steps: Calculate the mass change caused by carbon dioxide being bound by pores in a structurally confined region. (Formula 2); in, Indicates the porosity of the sealed area; Indicates the saturation of bound gas in the sealed area; Indicates the migration range of the tectonic trap region. Total number of geological grids in the direction, express Numbering of directional geological grids; Indicates the migration range of the tectonic trap region. Total number of geological grids in the direction, express Numbering of directional geological grids; Indicates the migration range of the tectonic trap region. Total number of geological grids in the direction, express Numbering of directional geological grids; Indicates coordinates as The volume of the geological grid; This indicates the density of formation water in the sealed area; Indicates coordinates as Carbon dioxide density at the geological grid.

[0046] To simplify the calculation, the mass change caused by carbon dioxide being bound by pores in the structural trap is calculated based on the porosity, bound gas saturation, formation water density, and carbon dioxide density distribution of the sealed area. This calculation also includes the following steps: By utilizing carbon dioxide density distribution, the mean carbon dioxide density of each geological grid within the migration range of the tectonic trap is calculated to obtain the average carbon dioxide density within the migration range of the tectonic trap. ; Will The value is taken as the average density of carbon dioxide within the transport range of the structural trap region. .

[0047] Based on the above embodiments, the first coefficient can be expressed as: (Formula 3).

[0048] In one specific embodiment of this application, step 108, calculating the actual area of ​​carbon dioxide overflow based on the first coefficient, the solubility of carbon dioxide in formation water, and the density distribution of carbon dioxide, may include the following steps: The total amount of carbon dioxide stored within the migration range of the tectonic trap area is calculated based on the first coefficient, the solubility of carbon dioxide in formation water, and the density distribution of carbon dioxide. The residual gaseous carbon dioxide in the potential overflow zone is calculated based on the total carbon dioxide injection, the total amount of carbon dioxide stored within the migration range of the structural trap, the carbon dioxide density distribution, and the first coefficient. The actual area of ​​carbon dioxide overflow is calculated based on the residual gaseous content of carbon dioxide in the potential overflow zone, the first extension thickness, and the first coefficient.

[0049] For example, calculating the total amount of carbon dioxide within the migration range of a structural trap based on a first coefficient, the solubility of carbon dioxide in formation water, and the carbon dioxide density distribution may include the following steps: Calculate the sum of the tectonic and residual gaseous carbon dioxide reserves within the migration range of the tectonic trap region. (Formula 4); Calculate the amount of formation water within the migration range of the tectonic trap area. (Formula 5); Calculate the amount of dissolved matter within the migration range of the structural trap region (dissolved matter content). (Formula 6); Calculate the sum of the structural occurrence, residual gaseous occurrence, and dissolved occurrence obtained from the above steps, and take the sum as the total occurrence of carbon dioxide within the migration range of the structural trap region. in, The total volume of the geological grid representing the migration range of the tectonic trap area; Indicates the porosity of the sealed area; Indicates the saturation of bound gas in the sealed area; Indicates the first coefficient; This represents the average carbon dioxide density of the tectonic trap area, obtained by averaging the carbon dioxide density of each geological grid within the migration range of the tectonic trap area using carbon dioxide density distribution. This indicates the density of formation water in the sealed area; This indicates the solubility of carbon dioxide in formation water; This indicates the amount of residual gaseous matter within the migration range of the structural trap region; This indicates the amount of tectonic deposits within the migration range of a tectonic trap region.

[0050] For example, calculating the residual gaseous carbon dioxide in the potential overflow zone based on the total carbon dioxide injection volume, the total carbon dioxide accumulation within the migration range of the structural trap area, the carbon dioxide density distribution, and a first coefficient may include the following steps: The difference between the total amount of carbon dioxide injected and the total amount of carbon dioxide stored within the migration range of the structural trap area is taken as the amount of carbon dioxide entering the potential overflow area. Calculate the residual gaseous quantity of carbon dioxide in the potential overflow zone. (Formula 7); in, This indicates the amount of carbon dioxide entering the potential overflow area; This represents the average carbon dioxide density of the potential overflow area, obtained by taking the mean value of the carbon dioxide density of each geological grid within the potential overflow area using the carbon dioxide density distribution. Indicates the saturation of bound gas in the sealed area; Indicates the first coefficient; This indicates the density of formation water in the sealed area; This indicates the solubility of carbon dioxide in formation water.

[0051] For example, when calculating the area of ​​the actual carbon dioxide overflow region based on the residual gaseous quantity of carbon dioxide in the potential overflow zone, the first extension thickness, and the first coefficient, the following formula is used: (Form 8); in, This represents the area of ​​the actual carbon dioxide overflow. Indicates the first extended thickness; This indicates the amount of residual gaseous carbon dioxide in the potential overflow area; This represents the average carbon dioxide density of the potential overflow area, obtained by taking the mean value of the carbon dioxide density of each geological grid within the potential overflow area using the carbon dioxide density distribution. Indicates the porosity of the sealed area; Indicates the saturation of bound gas in the sealed area; This represents the first coefficient.

[0052] Figure 2 A second flowchart illustrating a method for predicting the range of carbon dioxide transport in saline aquifers according to an embodiment of this application is shown. Figure 2As shown in the embodiments of this application, a method for predicting the range of carbon dioxide transport in saline aquifers is provided. Based on the above embodiments, the method further includes the following steps: Step 112: Combining the distribution of gravity monitoring points and the distribution of gravity anomaly points in the storage area determined by gravity anomaly data, the migration range of carbon dioxide in the structural trap area and the migration range of carbon dioxide in the potential overflow area are drawn to obtain a rectangular migration range. Step 114: Using the geological characteristics of the sealed area, the rectangular migration range obtained in step 112 is corrected. The geological characteristics include the source direction, sand body distribution characteristics, and fault distribution.

[0053] As in the above embodiment, by drawing the migration range, it is convenient for operators to observe the migration of carbon dioxide and identify leakage risks in a timely manner.

[0054] Figure 3 This illustration schematically depicts a technical roadmap for predicting the carbon dioxide transport range in saline aquifers according to an embodiment of this application, representing a specific application example of the above embodiments. Figure 3 As shown, in this application example, the method for predicting the range of carbon dioxide transport in saline aquifers includes the following steps: Step A1, sample acquisition, specifically refers to acquiring formation water samples and core samples from the carbon dioxide sequestration area.

[0055] Step A2, experimental analysis, specifically includes: A2.1 The collected formation water samples were analyzed to obtain the salinity, salt ion composition, and density of the formation water samples. Table 1 shows the measurement results of the physical properties of the formation water samples.

[0056] Table 1

[0057] A2.2. The solubility of carbon dioxide in the saline aquifer is obtained through calculation or measurement. In one application example, the temperature and pressure in the middle of the saline aquifer were 55℃ and 16MPa, respectively. Under these conditions, the solubility of carbon dioxide in the formation water was 0.31 mol / L, which translates to 13.64 kg / m³. 3 The mass of dissolved carbon dioxide in 1 kg of formation water is .

[0058] A2.3 Measuring the porosity of core samples and penetration rate The porosity was 0.15 and the permeability was 9.2 mD.

[0059] A2.4. Saturate the core sample with formation water and conduct a high-temperature and high-pressure core displacement experiment to obtain the relative permeability curves of carbon dioxide and formation water.

[0060] A2.5. Based on the relative permeability curve, the bound gas saturation of carbon dioxide in the core sample saturated with formation water is obtained. This bound gas saturation is considered to be the bound gas saturation of carbon dioxide in the porous medium under saline aquifer conditions. , This represents the minimum carbon dioxide saturation within the carbon dioxide transport range; in the application example, the measured value is 0.18.

[0061] Step A3, model building, specifically includes: A3.1, Based on the porosity of the carbon dioxide storage area Penetration rate By combining well logging interpretation data, maps, and other materials, a geological model of the carbon dioxide sequestration area is constructed, such as... Figure 4 As shown, the geological model of the constructed carbon dioxide storage area includes the structural trap area of ​​the anticline structure where the injection well is located and the potential overflow area obtained after the potential overflow path is extended outward by a certain area.

[0062] A3.2, Dividing the established geological model A three-dimensional grid ensures that gravity measurement points are distributed within different grids.

[0063] A3.3. Based on the geological model of the carbon dioxide sequestration area, input the fluid properties obtained in step A2, and establish the fluid transport control equations considering gravity to construct a numerical simulation model for carbon dioxide sequestration in a saline aquifer. The establishment of the numerical simulation model can refer to the establishment process of the black oil model for oil and gas reservoirs; the specific establishment process will not be elaborated further.

[0064] Step A4, data analysis, specifically includes: A4.1 Divide the carbon dioxide sequestration area of ​​the saline aquifer into a structural trap zone and a potential overflow zone. Generally, during short-term injection, the time-consuming mineralization and sequestration mechanism is ignored. The occurrence state of carbon dioxide in the structural trap zone includes structural occurrence, residual gaseous occurrence, and dissolved occurrence. The occurrence state of carbon dioxide in the potential overflow zone includes residual gaseous occurrence and dissolved occurrence.

[0065] A4.2. Using a numerical simulation model, calculate the pressure-driven process during carbon dioxide injection and the gravity-driven process after injection stops, to obtain the vertical thickness of the overflowing carbon dioxide in the potential overflow zone. (First extended thickness), combined with geological model structural undulations to calculate the structural trap area. Vertical thickness (The thickness of carbon dioxide transport in the structural trap).

[0066] according to Figure 4 The structural morphology of the saline aquifer shown is illustrated, and the structural traps are plotted. and potential overflow areas A simplified vertical cross-sectional diagram, as shown below. Figure 5 As shown. Figure 5 In the diagram, A1 and A3 are two structural low points on the anticline profile, and A2 is the highest point. A point A1, the relatively shallower of the two low points, is selected. A straight line is drawn through A1, intersecting the anticline profile at point B. The migration range of the structural trap area is the A1A2BDC1 region, and the potential overflow area consists of the BDG and A1C1FE regions. With carbon dioxide injection, carbon dioxide first fills the A1A2B region and then overflows through point A1 to point E. After injection stops, the carbon dioxide migration range is the A2EFG region. In this application example, The area of ​​the confined region is equal to the area of ​​the plane containing A1B, and the area of ​​the potential overflow region is the area of ​​the plane containing GF minus the area of ​​the plane containing A1B. The height of the potential overflow region (first extension thickness) is also considered. The height of the migration range within the structural trap zone ,according to Figure 4 As shown in the geological model, A2O = 20m, then... .

[0067] A4.3. Based on the established geological model, the migration area of ​​the tectonic trap zone is obtained based on the tectonic undulation morphology. In this application example, based on... Figure 4 Geological structure and Figure 5 The migration range of the structural trap region is shown in the figure. The transport area of ​​the structural trap region was calculated. 2.7×10 6 m 2 .

[0068] A4.4. Based on the mesh size of the numerical simulation model, the volume of a single mesh can be calculated as follows: In this application example, a uniformly sized grid of 50 m × 50 m × 4 m is used. The volume of a single grid cell is then... .

[0069] A4.5 Calculate the temperature and pressure of different grids based on the geothermal gradient and geopressure gradient of the sealed area, respectively. and In this application example, the calculated minimum temperature for each grid is 54.2℃, the maximum temperature is 55.8℃, the minimum pressure is 15.3MPa, and the maximum pressure is 16.7MPa.

[0070] A4.6. Carbon dioxide injection leads to a decrease in fluid density within the transport range, and gravity data on the plane shows a negative anomaly. Figure 4 The geological model shown indicates that it is located within the migration range of a tectonic trap. The negative gravity anomaly point number and its location in the potential overflow area The negative gravity anomaly points within the area are numbered. Based on the law of universal gravitation, the gravity anomaly values ​​are determined... Calculate the change in fluid density at different locations on the plane. Specifically, the gravity measurement points are as follows: Figure 6 As shown. According to gravity measurements, negative gravity anomalies appear at points 3-10 and 16-22. These are within the structural trap area. The negative gravity anomaly points within the potential overflow area are 4~9 and 17~21. The negative gravity anomaly points within the area are 3, 10, 16, and 22. In this application example, the maximum fluid density change at different locations is 0.004 kg / L, and the minimum fluid density change is 0.002 kg / L.

[0071] A4.7 Under the assumption of short-term storage conditions, construct a confined area. Internal carbon dioxide occurrence states include tectonic occurrence, residual gas occurrence, and dissolved occurrence, as well as potential overflow zones. The internal carbon dioxide occurrence states include residual gas occurrence and dissolved occurrence.

[0072] Step A5, determining the transport range, specifically includes: A5.1 Calculation Mesh volume at location : ; in, To construct the migration range of the trap region The total number of grid cells in the inward z-direction; for The mesh volume of the k-th layer in the z-direction at location. Specifically, the volume of a single mesh. Based on the migration range of the structural trap area The minimum number of inward vertical upward grid cells is 1, and the maximum is 5. Therefore... Minimum is The maximum is .

[0073] A5.2, by and Calculate the migration range of the structural trap region Average change in internal fluid density : ; ; in, and They are structural trap regions The total number of grid cells in the inner x and y directions; and On the plane respectively The total thickness corresponding to the grid is The total grid volume and the change in average fluid density within the grid; To construct the migration range of the trap region Total volume of the inner grid. Specifically, the migration range of the constructed trap region. The total number of internal grids is 213, and the total volume is... The migration range of the structural trap region was calculated. The average change in internal fluid density is 0.003 kg / L. Potential overflow area. The average change in internal fluid density is 0.002 kg / L.

[0074] A5.3, Based on grid pressure Calculate carbon dioxide density Structural trap regions Internal average carbon dioxide density and overflow area Average carbon dioxide density within Specifically, grid pressure The calculations are shown in A4.5. The minimum pressure of the model is 15.3 MPa, and the maximum pressure is 16.7 MPa. The carbon dioxide density under the minimum and maximum pressures of this model is obtained from flash evaporation calculations. The maximum concentration was 0.687 kg / L, and the minimum concentration was 0.603 kg / L. This indicates the migration range within the structural trap area. The average density of carbon dioxide inside is 0.627 kg / L, potential overflow area Internal average carbon dioxide density .

[0075] A5.4 Calculate the first coefficient In the application example, the volume of each grid is... and by adopting Replace carbon dioxide density in different grids Simplify the calculation: ; A5.5, in the structural trap region Both residual gaseous occurrence and tectonic occurrence are the main reasons for the significant decrease in fluid density, therefore, in tectonic trap regions... The internal structure does not distinguish between residual gaseous occurrences and tectonic occurrences. Calculation of tectonic trap regions is performed. Internal residual gaseous carbon dioxide and construction of endowment sum : ；； in, The measured core porosity is the average porosity from the geological model. To construct a closed region Total amount of carbon dioxide in the internal gas phase.

[0076] A5.6, Temperature based on geological model grid and pressure Calculate the average temperature and average pressure : ; .

[0077] A5.7, Based on the average temperature of the model mesh and average pressure Calculate the solubility of carbon dioxide in salt water. In the application example, using Setschenow's law, the solubility was calculated to be 0.31 mol / L, which translates to a mass of 13.64 kg / m³. 3 That is, the amount of soluble water per unit mass of formation water kg of carbon dioxide.

[0078] A5.8 Calculate the migration range of the structural trap region Inland water volume .

[0079] .

[0080] A5.9, Based on the solubility of carbon dioxide in salt water and the range of migration in the tectonic trap region Inland water volume Calculate the construction of closed regions Internal dissolved carbon dioxide content : .

[0081] A5.10 Calculate the potential overflow area Internal carbon dioxide : ; in, This indicates the total amount of carbon dioxide injected. In this application example, .

[0082] A5.11. Assume the ratio of gaseous carbon dioxide to dissolved carbon dioxide is equal in the constructed trap zone and the potential overflow zone. The potential overflow zone is known to contain... Calculate carbon dioxide and Internal gas phase carbon dioxide With solubility The ratio can be used to calculate the potential overflow area. Internal residual gaseous carbon dioxide : .

[0083] A5.12 Calculation of potential overflow area from material balance Internal dissolved carbon dioxide content : .

[0084] A5.13 Calculate the area of ​​the actual carbon dioxide overflow. : .

[0085] A5.14 Calculate the carbon dioxide transport area .

[0086] A5.15 Calculate the carbon dioxide transport thickness ,in, To construct the migration range of the trap region Maximum inner thickness.

[0087] A5.16. Based on the layout of monitoring points in the gravity detection area and the location of negative gravity anomaly data points, draw a rectangular carbon dioxide transport range, such as... Figure 7 As shown.

[0088] A5.17. Based on the area of ​​the carbon dioxide transport region Carbon dioxide transport thickness Based on the source direction, sand body distribution characteristics, and fault distribution, plot the lateral and vertical migration ranges of carbon dioxide. The planar distribution of the carbon dioxide migration range is shown below. Figure 8 As shown, the thickness of carbon dioxide transport in the vertical direction .

[0089] Figure 9 A schematic block diagram illustrating the composition of a saline aquifer carbon dioxide transport range prediction device according to an embodiment of this application is shown. Figure 9 As shown, the saline aquifer carbon dioxide transport range prediction device 400 provided in this application embodiment includes: Modeling module 410 is used to construct a numerical simulation model for carbon dioxide sequestration in a saline aquifer. The carbon dioxide sequestration area obtained through geological modeling in the numerical simulation model includes a tectonic trap area and a potential overflow area. The simulation module 420 is used to simulate the carbon dioxide injection process using the numerical simulation model to obtain the first extension thickness and the migration range of carbon dioxide in the structural trap area. The first extension thickness is the extension thickness of carbon dioxide reaching the potential overflow area in the direction parallel to the well depth of the carbon dioxide injection well. Density distribution calculation module 430 is used to calculate the carbon dioxide density distribution of the storage area using the formation pressure data of the storage area; The first coefficient determination module 440 is used to determine the proportion of the mass change caused by carbon dioxide being bound by pores within the transport range of the structural trap area to the total mass change within the transport range of the structural trap area based on the gravity anomaly data of the sealed area, the carbon dioxide density distribution, and the transport range of carbon dioxide within the structural trap area, and to determine the proportion as the first coefficient. The migration range determination module 450 is used to calculate the actual overflow area of ​​carbon dioxide based on the first coefficient, the solubility of carbon dioxide in formation water, and the density distribution of carbon dioxide, so as to obtain the migration range of carbon dioxide in the potential overflow area.

[0090] In one specific embodiment, determining the proportion of the mass change caused by carbon dioxide being confined by pores within the structural trap's migration range to the total mass change within the structural trap's migration range, based on gravity anomaly data of the sealed area, carbon dioxide density distribution, and the migration range of carbon dioxide within the structural trap, and defining this proportion as a first coefficient, includes: Calculate the fluid density change at different locations in the sealed area based on the gravity anomaly data of the sealed area; Calculate the total mass change within the transport range of the structural trap region based on the fluid density change; The porosity, bound gas saturation, and formation water density of the sealed area were obtained. The mass change caused by carbon dioxide being bound by pores within the migration range of the structural trap area is calculated based on the porosity, bound gas saturation, formation water density, and carbon dioxide density distribution of the sealed area. The ratio of the total mass change within the migration range of the tectonic trap to the mass change caused by carbon dioxide being confined by pores within the migration range of the tectonic trap is calculated, and this ratio is used as the first coefficient.

[0091] In one specific embodiment, calculating the total mass change within the transport range of the constructed trap region based on the fluid density change includes: Calculate the average fluid density change at different locations within the migration range of the structural trap within the sealed area to obtain the average fluid density change within the migration range of the structural trap. ; Total volume of geological grid for calculating the migration range of tectonic traps ; Calculate the total mass change within the transport range of the constructed trap region. .

[0092] In one specific embodiment, the calculation of the mass change caused by carbon dioxide being bound by pores within the migration range of the structural trap area, based on the porosity, bound gas saturation, formation water density, and carbon dioxide density distribution of the sealed area, includes: Calculate the mass change caused by carbon dioxide being bound by pores within the transport range of a structurally confined region. ; in, This indicates the porosity of the sealed area; This indicates the saturation of the binding gas in the sealed area; Indicates the migration range of the tectonic trap region. Total number of geological grids in the direction, express Numbering of directional geological grids; Indicates the migration range of the tectonic trap region. Total number of geological grids in the direction, express Numbering of directional geological grids; Indicates the migration range of the tectonic trap region. Total number of geological grids in the direction, express Numbering of directional geological grids; Indicates coordinates as The volume of the geological grid; This indicates the density of formation water in the sealed area; Indicates coordinates as Carbon dioxide density at the geological grid.

[0093] In one specific embodiment, calculating the actual area of ​​carbon dioxide overflow based on the first coefficient, the solubility of carbon dioxide in formation water, and the density distribution of carbon dioxide includes: The total amount of carbon dioxide stored within the migration range of the tectonic trap area is calculated based on the first coefficient, the solubility of carbon dioxide in formation water, and the density distribution of carbon dioxide. The residual gaseous carbon dioxide in the potential overflow zone is calculated based on the total carbon dioxide injection, the total amount of carbon dioxide stored within the migration range of the structural trap, the carbon dioxide density distribution, and the first coefficient. The actual area of ​​carbon dioxide overflow is calculated based on the residual gaseous content of carbon dioxide in the potential overflow zone, the first extension thickness, and the first coefficient.

[0094] In one specific embodiment, the calculation of the total carbon dioxide content within the migration range of the structural trap area based on the first coefficient, the solubility of carbon dioxide in formation water, and the carbon dioxide density distribution includes: Calculate the sum of the tectonic and residual gaseous carbon dioxide reserves within the migration range of the tectonic trap region. ; Calculate the amount of formation water within the migration range of the tectonic trap area. ; Calculate the amount of dissolved state within the migration range of the constructed trap region. ; The sum of the tectonic occurrence, residual gaseous occurrence, and dissolved occurrence of carbon dioxide within the migration range of the tectonic trap is calculated, and the sum is taken as the total occurrence of carbon dioxide within the migration range of the tectonic trap. in, The total volume of the geological grid representing the migration range of the tectonic trap area; This indicates the porosity of the sealed area; This indicates the saturation of the binding gas in the sealed area; Indicates the first coefficient; This refers to the average carbon dioxide density of the tectonic trap area, obtained by averaging the carbon dioxide density of each geological grid within the migration range of the tectonic trap area using the aforementioned carbon dioxide density distribution. This indicates the density of formation water in the sealed area; This indicates the solubility of carbon dioxide in formation water; This indicates the amount of residual gaseous matter within the migration range of the structural trap region; This indicates the amount of tectonic deposits within the migration range of a tectonic trap region.

[0095] In one specific embodiment, the calculation of the residual gaseous carbon dioxide in the potential overflow zone based on the total carbon dioxide injection volume, the total amount of carbon dioxide stored within the migration range of the structural trap area, the carbon dioxide density distribution, and a first coefficient includes: The difference between the total amount of carbon dioxide injected and the total amount of carbon dioxide stored within the migration range of the structural trap area is taken as the amount of carbon dioxide entering the potential overflow area. Calculate the residual gaseous quantity of carbon dioxide in the potential overflow zone. ; in, This indicates the amount of carbon dioxide entering the potential overflow area; This represents the average carbon dioxide density of the potential overflow area, obtained by taking the mean value of the carbon dioxide density of each geological grid within the potential overflow area using the aforementioned carbon dioxide density distribution. This indicates the saturation of the binding gas in the sealed area; Indicates the first coefficient; This indicates the density of formation water in the sealed area; This indicates the solubility of carbon dioxide in formation water.

[0096] In one specific embodiment, the calculation of the actual overflow area of ​​carbon dioxide based on the residual gaseous quantity of carbon dioxide in the potential overflow zone, the first extension thickness, and the first coefficient utilizes the following formula: ; in, This represents the area of ​​the actual carbon dioxide overflow. Indicates the first extended thickness; This indicates the amount of residual gaseous carbon dioxide in the potential overflow area; This represents the average carbon dioxide density of the potential overflow area, obtained by taking the mean value of the carbon dioxide density of each geological grid within the potential overflow area using the aforementioned carbon dioxide density distribution. This indicates the porosity of the sealed area; This indicates the saturation of the binding gas in the sealed area; This represents the first coefficient.

[0097] In one specific embodiment, the numerical simulation model for constructing a saline aquifer for carbon dioxide sequestration includes a carbon dioxide sequestration area obtained through geological modeling, comprising a tectonic trap zone and a potential overflow zone, including: Obtain the formation physical properties and fluid physical properties of the carbon dioxide storage area; The geological properties of the carbon dioxide sequestration area are used as the geological attributes of each volume element in the geological model to construct a geological model of the carbon dioxide sequestration area. The carbon dioxide sequestration area in the geological model includes structural trap areas and potential overflow areas. By inputting the fluid properties of the carbon dioxide sequestration area and the pre-constructed fluid transport control equations into the geological model, a numerical simulation model of carbon dioxide sequestration in a saline aquifer is obtained.

[0098] In one specific embodiment, the numerical simulation model is used to simulate the carbon dioxide injection process to obtain a first extension thickness and the migration range of carbon dioxide in the structural trap zone. The first extension thickness is the extension thickness of carbon dioxide reaching the potential overflow zone in the direction parallel to the well depth of the carbon dioxide injection well, including: The pressure-driven process during carbon dioxide injection and the gravity-driven process after injection is stopped are simulated using the numerical simulation model to obtain the first expansion thickness, which is the expansion thickness of carbon dioxide reaching the potential overflow zone in the direction parallel to the depth of the carbon dioxide injection well. The migration thickness of carbon dioxide in the structural trap is calculated based on the structural undulation parameters of the geological model of the carbon dioxide storage area obtained by geological modeling in the numerical simulation model and the first extended thickness. The direction of this thickness is parallel to the well depth direction of the carbon dioxide injection well. The migration area of ​​carbon dioxide in the tectonic trap area is calculated based on the tectonic undulation parameters of the geological model. The migration range of carbon dioxide in the structural trap can be obtained by measuring the migration thickness and area of ​​carbon dioxide in the structural trap.

[0099] In one specific embodiment, the device further includes: The drawing module is used to combine the distribution of gravity monitoring points and the distribution of gravity anomaly points in the sealed area determined by gravity anomaly data to draw the migration range of carbon dioxide in the constructed trap area and the migration range of carbon dioxide in the potential overflow area, and obtain a rectangular migration range. The correction module is used to correct the rectangular migration range by utilizing the geological features of the sealed area, including the source direction, sand body distribution characteristics, and fault distribution.

[0100] Figure 10 A schematic block diagram of a computer device according to an embodiment of the present application is shown. In one embodiment, a computer device is provided, which may be a terminal, and its internal structure diagram may be as shown below. Figure 10As shown, the computer device includes a processor A01, a network interface A02, a display screen A04, an input device A05, and a memory (not shown) connected via a system bus. The processor A01 provides computing and control capabilities. The memory includes internal memory A03 and a non-volatile storage medium A06. The non-volatile storage medium A06 stores an operating system B01 and a computer program B02. The internal memory A03 provides an environment for the operation of the operating system B01 and the computer program B02 stored in the non-volatile storage medium A06. The network interface A02 is used for communication with external terminals via a network connection. When the computer program is executed by the processor A01, it implements a method for predicting the range of carbon dioxide transport in a saline aquifer. The display screen A04 can be a liquid crystal display (LCD) or an e-ink display. The input device A05 can be a touch layer covering the display screen, buttons, a trackball, or a touchpad mounted on the computer device casing, or an external keyboard, touchpad, or mouse.

[0101] Those skilled in the art will understand that Figure 10 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0102] In one embodiment, the saline aquifer carbon dioxide transport range prediction device 400 provided in this application can be implemented as a computer program, which can be implemented in, for example... Figure 10 The device operates on the computer shown. The computer's memory can store various program modules that make up the saline aquifer carbon dioxide migration range prediction device. The computer program, composed of these program modules, causes the processor to execute the steps in the saline aquifer carbon dioxide migration range prediction methods of the various embodiments of this application described in this specification.

[0103] In one embodiment, this application also provides a machine-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method for predicting the range of carbon dioxide transport in saline aquifers as described in the above embodiments.

[0104] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0105] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application 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.

[0106] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0107] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A method for predicting the range of carbon dioxide transport in saline aquifers, characterized in that, include: A numerical simulation model for carbon dioxide sequestration in a saline aquifer is constructed. The carbon dioxide sequestration area obtained through geological modeling in the numerical simulation model includes tectonic trap areas and potential overflow areas. The carbon dioxide injection process was simulated using the numerical simulation model to obtain the first extension thickness and the migration range of carbon dioxide in the structural trap area. The first extension thickness is the extension thickness of carbon dioxide reaching the potential overflow area in the direction parallel to the well depth of the carbon dioxide injection well. The carbon dioxide density distribution in the sealed area was calculated using the formation pressure data of the sealed area. Based on the gravity anomaly data of the sealed area, the carbon dioxide density distribution, and the migration range of carbon dioxide in the structural trap area, the proportion of the mass change caused by carbon dioxide being bound by pores in the migration range of the structural trap area is determined to be the proportion of the total mass change in the migration range of the structural trap area, and the proportion is determined as the first coefficient. The actual area of ​​carbon dioxide overflow is calculated based on the first coefficient, the solubility of carbon dioxide in formation water, and the density distribution of carbon dioxide, so as to obtain the range of carbon dioxide migration in the potential overflow area.

2. The method according to claim 1, characterized in that, The method involves determining the proportion of the mass change caused by carbon dioxide being confined by pores within the structural trap's migration range, based on gravity anomaly data, carbon dioxide density distribution, and the migration range of carbon dioxide within the sealed area, within the total mass change within the structural trap's migration range. This proportion is then defined as a first coefficient, including: Calculate the fluid density change at different locations in the sealed area based on the gravity anomaly data of the sealed area; Calculate the total mass change within the transport range of the structural trap region based on the fluid density change; The porosity, bound gas saturation, and formation water density of the sealed area were obtained. The mass change caused by carbon dioxide being bound by pores within the migration range of the structural trap area is calculated based on the porosity, bound gas saturation, formation water density, and carbon dioxide density distribution of the sealed area. The ratio of the total mass change within the migration range of the tectonic trap to the mass change caused by carbon dioxide being confined by pores within the migration range of the tectonic trap is calculated, and this ratio is used as the first coefficient.

3. The method according to claim 2, characterized in that, The calculation of the total mass change within the transport range of the structural trap region based on the fluid density change includes: Calculate the average fluid density change at different locations within the migration range of the structural trap within the sealed area to obtain the average fluid density change within the migration range of the structural trap. ; Total volume of geological grid for calculating the migration range of tectonic traps ; Calculate the total mass change within the transport range of the constructed trap region. .

4. The method according to claim 2, characterized in that, The calculation of the mass change caused by carbon dioxide being bound by pores within the migration range of the structural trap area, based on the porosity, bound gas saturation, formation water density, and carbon dioxide density distribution of the sealed area, includes: Calculate the mass change caused by carbon dioxide being bound by pores within the transport range of a structurally confined region. ; in, This indicates the porosity of the sealed area; This indicates the saturation of the binding gas in the sealed area; Indicates the migration range of the tectonic trap region. Total number of geological grids in the direction, express Numbering of directional geological grids; Indicates the migration range of the tectonic trap region. Total number of geological grids in the direction, express Numbering of directional geological grids; Indicates the migration range of the tectonic trap region. Total number of geological grids in the direction, express Numbering of directional geological grids; Indicates coordinates as The volume of the geological grid; This indicates the density of formation water in the sealed area; Indicates coordinates as Carbon dioxide density at the geological grid.

5. The method according to any one of claims 1 to 4, characterized in that, The calculation of the actual area of ​​carbon dioxide overflow based on the first coefficient, the solubility of carbon dioxide in formation water, and the density distribution of carbon dioxide includes: The total amount of carbon dioxide stored within the migration range of the tectonic trap area is calculated based on the first coefficient, the solubility of carbon dioxide in formation water, and the density distribution of carbon dioxide. The residual gaseous carbon dioxide in the potential overflow zone is calculated based on the total carbon dioxide injection, the total amount of carbon dioxide stored within the migration range of the structural trap, the carbon dioxide density distribution, and the first coefficient. The actual area of ​​carbon dioxide overflow is calculated based on the residual gaseous content of carbon dioxide in the potential overflow zone, the first extension thickness, and the first coefficient.

6. The method according to claim 5, characterized in that, The calculation of the total carbon dioxide reserves within the migration range of the structural trap area, based on the first coefficient, the solubility of carbon dioxide in formation water, and the carbon dioxide density distribution, includes: Calculate the sum of the tectonic and residual gaseous carbon dioxide reserves within the migration range of the tectonic trap region. ; Calculate the amount of formation water within the migration range of the tectonic trap area. ; Calculate the amount of dissolved state within the migration range of the constructed trap region. ; The sum of the tectonic occurrence, residual gaseous occurrence, and dissolved occurrence of carbon dioxide within the migration range of the tectonic trap is calculated, and the sum is taken as the total occurrence of carbon dioxide within the migration range of the tectonic trap. in, The total volume of the geological grid representing the migration range of the tectonic trap area; This indicates the porosity of the sealed area; This indicates the saturation of the binding gas in the sealed area; Indicates the first coefficient; This refers to the average carbon dioxide density of the tectonic trap area, obtained by averaging the carbon dioxide density of each geological grid within the migration range of the tectonic trap area using the aforementioned carbon dioxide density distribution. This indicates the density of formation water in the sealed area; This indicates the solubility of carbon dioxide in formation water; This indicates the amount of residual gaseous matter within the migration range of the structural trap region; This indicates the amount of tectonic deposits within the migration range of a tectonic trap region.

7. The method according to claim 5, characterized in that, The calculation of the residual gaseous carbon dioxide in the potential overflow zone based on the total carbon dioxide injection volume, the total carbon dioxide accumulation within the structural trap's migration range, the carbon dioxide density distribution, and the first coefficient includes: The difference between the total amount of carbon dioxide injected and the total amount of carbon dioxide stored within the migration range of the structural trap area is taken as the amount of carbon dioxide entering the potential overflow area. Calculate the residual gaseous quantity of carbon dioxide in the potential overflow zone. ; in, This indicates the amount of carbon dioxide entering the potential overflow area; This represents the average carbon dioxide density of the potential overflow area, obtained by taking the mean value of the carbon dioxide density of each geological grid within the potential overflow area using the aforementioned carbon dioxide density distribution. This indicates the saturation of the binding gas in the sealed area; Indicates the first coefficient; This indicates the density of formation water in the sealed area; This indicates the solubility of carbon dioxide in formation water.

8. The method according to claim 5, characterized in that, When calculating the area of ​​the actual carbon dioxide overflow region based on the residual gaseous carbon dioxide content in the potential overflow zone, the first expansion thickness, and the first coefficient, the following formula is used: ； in, This represents the area of ​​the actual carbon dioxide overflow. Indicates the first extended thickness; This indicates the amount of residual gaseous carbon dioxide in the potential overflow area; This represents the average carbon dioxide density of the potential overflow area, obtained by taking the mean value of the carbon dioxide density of each geological grid within the potential overflow area using the aforementioned carbon dioxide density distribution. This indicates the porosity of the sealed area; This indicates the saturation of the binding gas in the sealed area; This represents the first coefficient.

9. The method according to claim 1, characterized in that, The numerical simulation model for constructing a saline aquifer for carbon dioxide sequestration includes, through geological modeling, a carbon dioxide sequestration area comprising a tectonic trap zone and a potential overflow zone, including: Obtain the formation physical properties and fluid physical properties of the carbon dioxide storage area; The geological properties of the carbon dioxide sequestration area are used as the geological attributes of each volume element in the geological model to construct a geological model of the carbon dioxide sequestration area. The carbon dioxide sequestration area in the geological model includes structural trap areas and potential overflow areas. By inputting the fluid properties of the carbon dioxide sequestration area and the pre-constructed fluid transport control equations into the geological model, a numerical simulation model of carbon dioxide sequestration in a saline aquifer is obtained.

10. The method according to claim 1, characterized in that, The numerical simulation model is used to simulate the carbon dioxide injection process to obtain the first extension thickness and the migration range of carbon dioxide in the structural trap zone. The first extension thickness is the extension thickness of carbon dioxide reaching the potential overflow zone in the direction parallel to the well depth of the carbon dioxide injection well, including: The pressure-driven process during carbon dioxide injection and the gravity-driven process after injection is stopped are simulated using the numerical simulation model to obtain the first expansion thickness, which is the expansion thickness of carbon dioxide reaching the potential overflow zone in the direction parallel to the depth of the carbon dioxide injection well. The migration thickness of carbon dioxide in the structural trap is calculated based on the structural undulation parameters of the geological model of the carbon dioxide storage area obtained by geological modeling in the numerical simulation model and the first extended thickness. The direction of this thickness is parallel to the well depth direction of the carbon dioxide injection well. The migration area of ​​carbon dioxide in the tectonic trap area is calculated based on the tectonic undulation parameters of the geological model. The migration range of carbon dioxide in the structural trap can be obtained by measuring the migration thickness and area of ​​carbon dioxide in the structural trap.

11. The method according to claim 1, characterized in that, Also includes: Combining the distribution of gravity monitoring points and the distribution of gravity anomaly points within the sealed area determined by gravity anomaly data, the migration range of carbon dioxide in the constructed trap area and the migration range of carbon dioxide in the potential overflow area are plotted to obtain a rectangular migration range. The rectangular migration range is modified by utilizing the geological characteristics of the sealed area, including the source direction, sand body distribution characteristics, and fault distribution.

12. A device for predicting the range of carbon dioxide transport in a saline aquifer, characterized in that, include: The modeling module is used to construct a numerical simulation model for carbon dioxide sequestration in saline aquifers. The carbon dioxide sequestration area obtained through geological modeling in the numerical simulation model includes tectonic trap areas and potential overflow areas. The simulation module is used to simulate the carbon dioxide injection process using the numerical simulation model to obtain the first extension thickness and the migration range of carbon dioxide in the constructed trap area. The first extension thickness is the extension thickness of carbon dioxide reaching the potential overflow area in the direction parallel to the well depth of the carbon dioxide injection well. The density distribution calculation module is used to calculate the carbon dioxide density distribution of the storage area using the formation pressure data of the storage area. The first coefficient determination module is used to determine the proportion of the mass change caused by carbon dioxide being bound by pores within the transport range of the structural trap area to the total mass change within the transport range of the structural trap area based on the gravity anomaly data of the sealed area, the carbon dioxide density distribution, and the transport range of carbon dioxide within the structural trap area, and to determine the proportion as the first coefficient. The migration range determination module is used to calculate the actual overflow area of ​​carbon dioxide based on the first coefficient, the solubility of carbon dioxide in formation water, and the density distribution of carbon dioxide, so as to obtain the migration range of carbon dioxide in the potential overflow area.

13. The apparatus according to claim 12, characterized in that, include: The method involves determining the proportion of the mass change caused by carbon dioxide being confined by pores within the structural trap's migration range, based on gravity anomaly data, carbon dioxide density distribution, and the migration range of carbon dioxide within the sealed area, within the total mass change within the structural trap's migration range. This proportion is then defined as a first coefficient, including: Calculate the fluid density change at different locations in the sealed area based on the gravity anomaly data of the sealed area; Calculate the total mass change within the transport range of the structural trap region based on the fluid density change; The porosity, bound gas saturation, and formation water density of the sealed area were obtained. The mass change caused by carbon dioxide being bound by pores within the migration range of the structural trap area is calculated based on the porosity, bound gas saturation, formation water density, and carbon dioxide density distribution of the sealed area. The ratio of the total mass change within the migration range of the tectonic trap to the mass change caused by carbon dioxide being confined by pores within the migration range of the tectonic trap is calculated, and this ratio is used as the first coefficient.

14. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the method for predicting the range of carbon dioxide transport in saline aquifers as described in any one of claims 1-11.

15. A machine-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the method for predicting the range of carbon dioxide transport in saline aquifers according to any one of claims 1-11.

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