Quantitative characterization method for carbon dioxide-water-rock interaction inorganic precipitate and application

Abstract

The invention discloses a carbon dioxide water rock interaction inorganic precipitate quantitative characterization method, which comprises the following steps: acquiring basic physical property parameters of a target oil reservoir, quantifying the total carbon dioxide storage amount from a macroscopic angle, and establishing an indoor carbon dioxide water rock reaction experiment model to obtain basic physical property parameters of a core sample and formation water. The carbon dioxide mineralization burying amount is quantified from the microscopic perspective, meanwhile, the mineral saturation index is introduced to further determine the action mechanism and reaction rule of precipitation and dissolution and the reaction state of rock minerals in the carbon dioxide water rock reaction, and the reaction conditions and products of the carbon dioxide water solution and the minerals are determined. According to the quantitative characterization evaluation method, data are easy to obtain, the method practicability is high, the calculation model is novel, the problems that existing carbon dioxide water rock interaction inorganic precipitation is difficult to quantify, methods are not uniform, and connection with the macroscale is difficult to establish are solved, the pertinence is high, the evaluation method is scientific, and the method has important significance on development of oil and gas fields in China.

Description

Technical Field

[0001] The invention belongs to the technical field of oil and gas field development, and particularly relates to a quantitative characterization method for inorganic precipitation of carbon dioxide-water-rock interaction and application thereof. Background Art

[0002] In recent years, due to the large-scale burning of fossil fuels, the global greenhouse effect has intensified. Therefore, under the condition of meeting energy demand, reducing carbon dioxide emissions has become a key issue in slowing down global warming. Carbon dioxide capture, utilization and storage (CCUS) can effectively bury carbon while increasing oil recovery, and is a technical method with both social and economic benefits.

[0003] The study found that after entering the reservoir, carbon dioxide will continuously transfer mass with crude oil, occupying the pore volume of crude oil, so that most of the injected carbon dioxide exists in the form of free gas or supercritical gas. At the same time, the injected carbon dioxide continuously dissolves into the oil and water phases in contact, increasing the storage capacity of carbon dioxide, and then reacts with rock minerals to form carbonate minerals. Some asphaltene and carbonate precipitation causes the reservoir pores to be blocked, reducing the reservoir permeability and affecting the crude oil recovery rate.

[0004] At present, there are many indoor experimental studies on the reaction of carbon dioxide with formation water and rock, but they are generally qualitative analyses and lack quantitative evaluation methods. After carbon dioxide enters the reservoir, it reacts with rocks and formation water or the interaction of the three will consume carbon dioxide. The dominant mechanism among these three effects is still unclear, and the impact on the effect of carbon dioxide on oil recovery is still unclear. Theoretical research is separated from actual production, and a quantitative evaluation method for inorganic precipitation of carbon dioxide-formation water interaction is urgently needed.

[0005] Faced with increasingly harsh reservoir conditions, it is of great significance to fully study the changes and effects of the interaction between carbon dioxide, formation water and rocks on reservoir properties during the geological storage and oil recovery of carbon dioxide for the development of oil and gas fields in my country. Specifically, most onshore oil fields in China face problems such as poor reservoir properties, complex mining conditions and low crude oil recovery. In order to further solve existing problems and promote the development of existing technical levels, it is particularly important to clarify the microscopic mechanism of carbon dioxide storage, the change law of reservoir minerals, the state of water-rock reaction, and quantitatively characterize the inorganic precipitation that affects the flow channel of crude oil.

[0006] At present, for inorganic precipitation of CO2 formation water-rock interaction, quantitative analysis at the microscopic scale is difficult, and the inconsistent methods make it difficult to establish a connection with the macroscopic scale, which is very unfavorable for the accurate calculation of CO2 storage. The existing static high-pressure reactor experiments have certain limitations. In the development of reaction transport models, it is necessary to explain the potential multiphase restricted reactions, concentration gradients of each phase, and subsequent diffusion and migration behaviors by combining mineral-fluid interface phenomena. Therefore, a clear quantitative method is needed for the mechanism, experimental methods, and mathematical calculation methods of CO2 formation water interaction. Summary of the invention

[0007] In view of the above problems, the present invention provides a quantitative characterization method and application of inorganic precipitation of carbon dioxide-water-rock interaction. Through multi-angle data collection, indoor experiments and combined with mathematical models, the mineral saturation index is introduced to further evaluate the effects of precipitation and dissolution on reservoir rocks, and the inorganic precipitation and carbon dioxide storage in the carbon dioxide-water-rock reaction are quantitatively calculated, which solves the problems that the current evaluation method is limited to qualitative analysis and is separated from production. The characterization method overcomes the problems of difficulty in quantitative analysis at the microscopic scale, inconsistent methods, and difficulty in establishing a connection with the macroscopic scale. It is highly targeted, has a scientific evaluation method, clarifies the impact of precipitation on reservoir properties, and is of great significance to the development of oil and gas fields in my country.

[0008] In one aspect of the present invention, a method for quantitatively characterizing inorganic precipitation of carbon dioxide-water-rock interaction is provided, the method comprising:

[0009] S1. Select a target oil reservoir, obtain a core sample from the target oil reservoir, and collect basic physical property parameters of the target oil reservoir and the core sample;

[0010] S2. Prepare formation water corresponding to the core sample, saturate the core sample with the formation water, perform a carbon dioxide-water-rock reaction in a high-temperature and high-pressure reactor, separate the reaction product into solid and liquid, and collect basic physical property parameters of the solid part and the liquid part of the reaction product respectively;

[0011] S3. Based on the basic physical property parameters of the target oil reservoir, the total carbon dioxide storage capacity of the target oil reservoir is obtained; based on the basic physical property parameters of the core sample and the basic physical property parameters of the solid part of the reaction product, the mineralized carbon dioxide storage capacity of the target oil reservoir is obtained; based on the basic physical property parameters of the liquid part of the reaction product, the mineral saturation index is obtained, and then the quantitative characterization of the carbon dioxide-water-rock interaction is achieved from three dimensions: the total carbon dioxide storage capacity, the mineralized carbon dioxide storage capacity and the mineral saturation index.

[0012] As a specific implementation of the present invention, the basic physical property parameters of the target oil reservoir include oil reservoir area, oil reservoir thickness, reservoir porosity, oil reservoir irreducible water saturation, and density of carbon dioxide under oil reservoir conditions.

[0013] As a specific embodiment of the present invention, the basic physical properties of the core sample include porosity and mineral composition data, as well as carbon dioxide capture data of each component mineral obtained based on the mineral composition data; preferably, the porosity of the core sample is collected using a pore-permeability tester; preferably, the mineral composition data of the core sample is collected through an XRD test; preferably, by performing a thermogravimetric analysis test on each component mineral of the core sample, the maximum reaction amount that can be combined with carbon dioxide is obtained, that is, the carbon dioxide capture data of each component mineral.

[0014] As a specific embodiment of the present invention, the basic physical property parameters of the solid part of the reaction product include porosity data. Preferably, the porosity data of the solid part of the reaction product is collected using a pore-permeability tester.

[0015] As a specific embodiment of the present invention, the basic physical property parameters of the liquid part of the reaction product include ion composition data; preferably, the ion composition data of the liquid part of the reaction product is collected by EDTA complexometric titration and potentiometric analysis experiments.

[0016] As a specific embodiment of the present invention, the parameters of the high temperature and high pressure reactor are set to a temperature of 105° C. and a pressure of 3 MPa, and the reaction time is 12 days.

[0017] As a specific embodiment of the present invention, a method for obtaining the total carbon dioxide storage capacity of a target oil reservoir based on the basic physical property parameters of the target oil reservoir is to substitute the basic physical property parameters of the target oil reservoir into formula (1) for calculation:

[0018]

[0019] Where: M——total carbon dioxide storage, kg;

[0020] ρ——density of carbon dioxide under reservoir conditions, kg / m 3 ;

[0021] A——reservoir area, m 2 ;

[0022] h——reservoir thickness, m;

[0023] —— reservoir porosity;

[0024] S w ——Immobile water saturation of the reservoir.

[0025] As a specific embodiment of the present invention, based on the basic physical property parameters of the core sample and the basic physical property parameters of the solid part of the reaction product, a method for obtaining the mineralized storage capacity of carbon dioxide in the target reservoir is to substitute each basic physical property parameter into formulas (2) to (4) for calculation:

[0026]

[0027]

[0028] V i =S i ×h i ×(1-φ)×C (4);

[0029] Where: Q——Total carbon dioxide mineral storage in the target reservoir, kg;

[0030] Q i ——Carbon dioxide capture per unit volume of type i lithology and minerals, kg;

[0031] V i ——The volume of the i-th type of lithology and minerals in the target area, m 3 ;

[0032] x j ——The volume percentage of the jth mineral content in the rock;

[0033] y j ——Capacity of carbon dioxide captured by the jth mineral per unit volume in the rock, kg;

[0034] S i ——Oil reservoir area, m 2 ;

[0035] h i ——reservoir thickness, m;

[0036] - porosity;

[0037] C——reservoir heterogeneity coefficient.

[0038] As a specific embodiment of the present invention, based on the basic physical property parameters of the liquid part of the reaction product, the method for obtaining the mineral saturation index is to substitute the basic physical property parameters of the liquid part of the reaction product into formula (5) for calculation:

[0039] SI = lg (IAP / Ksp) (5);

[0040] Where: IAP is the product of the activities of anions and cations that make up the sparingly soluble salt in the liquid;

[0041] Ksp - the solubility equilibrium constant of sparingly soluble salts.

[0042] If SI<0, it indicates that the mineral is in an unsaturated state in the aqueous solution. Under the control of dissolution, the mineral's own components will dissolve into the groundwater solution, that is, the mineral will dissolve.

[0043] If SI = 0, it indicates that the mineral is in a state of solubility equilibrium in the aqueous solution, and the mineral continues to maintain a state of solubility equilibrium in the aqueous solution.

[0044] Considering the error of the calculation results of the mineral saturation index SI, when the SI value is between -0.5 and 0.5, it can be considered that the mineral and the aqueous solution have reached a quasi-equilibrium state.

[0045] When SI>0, it indicates that the mineral is in a supersaturated state in the aqueous solution, that is, the mineral is about to precipitate or is mainly precipitated. The saturation index method can be used to determine the dissolution state of the mineral component in the aqueous solution of this environment. At the same time, the SI value can also be used to determine the reaction state between water and rocks and minerals, thereby understanding the law of carbon dioxide water rock reaction.

[0046] Another aspect of the present invention provides application of the aforementioned quantitative characterization method in evaluating the physical properties of a target oil reservoir.

[0047] The beneficial effects of the present invention are:

[0048] The characterization method provided by the present invention collects the basic physical property parameters of the target oil reservoir to quantify the total storage of carbon dioxide from a macroscopic perspective, and obtains the basic physical property parameters of the core samples and formation water by constructing an indoor carbon dioxide water-rock reaction experimental model to quantify the storage of carbon dioxide mineralization from a microscopic perspective. At the same time, the mineral saturation index is introduced to further determine the mechanism of precipitation and dissolution, reaction law and reaction state of rock minerals in the carbon dioxide water-rock reaction, and clarify the reaction conditions and products of carbon dioxide aqueous solution and minerals. The quantitative characterization evaluation method is easy to obtain data, the method is highly practical, and the calculation model is novel. It solves the problems of the difficulty of quantitative inorganic precipitation of the current carbon dioxide water-rock interaction, the lack of uniformity of methods, and the difficulty of establishing a connection with the macroscopic scale. It is highly targeted and has a scientific evaluation method. It is of great significance for studying the changes and influences of the interaction between carbon dioxide and formation water and rocks on reservoir physical properties during carbon dioxide geological storage and oil recovery, as well as the development of oil and gas fields in my country. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] Example 1 Quantitative characterization of inorganic precipitation of carbon dioxide-water-rock interaction using total carbon dioxide storage

[0051] The target reservoir is the Shanxi Formation of Changqing Oilfield, and its basic parameters are as follows:

[0052] Table 1 Basic parameters of reservoir

[0053]

[0054]

[0055] Where: M——total carbon dioxide storage, kg;

[0056] ρ——density of carbon dioxide under reservoir conditions, kg / m 3 ;

[0057] A——reservoir area, m 2 ;

[0058] h——reservoir thickness, m;

[0059] —— reservoir porosity;

[0060] S w ——Immobile water saturation of the reservoir.

[0061] According to the above formula, the corresponding calculation software "Carbon Dioxide Storage Calculation Method Software V1.0 in Oil Reservoirs" (registration number: 2021SR1020876) was compiled, and the above values ​​were directly input into the calculation software. The result output was that the total carbon dioxide storage capacity was 115.8597t.

[0062] Example 2 Quantitative characterization of inorganic precipitation of carbon dioxide-water-rock interaction by carbon dioxide mineralization storage

[0063] Core samples were selected from the target reservoir to conduct a carbon dioxide-water-rock reaction experiment, as follows:

[0064] 1. Conduct porosity and permeability measurement, XRD and thermogravimetric analysis experiments on core samples to obtain basic physical property data. At the same time, CaCl2 type formation water is prepared indoors;

[0065] 2. Saturate the core with CaCl2-type formation water;

[0066] 3. Seal the saturated core samples and formation water in a high-pressure reactor, and inject carbon dioxide into the reactor at a constant pressure of 3MPa using a high-pressure gas cylinder controlled by a pressure reducing valve. Place the high-temperature and high-pressure reactor in a constant temperature box, set the temperature to 105°C, and react at a constant temperature for 12 days.

[0067] 4. After the reaction is completed, the gas is quickly released, and the rock samples after the reaction are taken for porosity and permeability measurement, and the aqueous solution after the reaction is taken for pH, EDTA complex titration, and potentiometric analysis experiments.

[0068] Through the above experimental steps, the obtained data are shown in the following table.

[0069] Table 2 Basic parameters of core samples

[0070] Core number Porosity% Permeability / mD Length / cm Diameter / cm <![CDATA[Volume / cm 3 > Dry weight / g S1 4.81 1.04 3.16 2.47 15.18 37.24 S2 7.39 2.79 3.58 2.47 17.20 40.71 S3 4.06 1.37 3.72 2.50 18.22 42.40 S4 5.72 1.13 3.41 2.50 16.70 40.42

[0071] Table 3 Comparison of permeability and porosity of core samples before and after reaction

[0072]

[0073] Table 4 Mineral component contents of core samples determined by XRD

[0074] Sample No. quartz(%) Potassium feldspar (%) Plagioclase(%) Hazeolite(%) Calcite(%) Total clay content (%) S1 39.0 13.5 27.9 4.3 10.5 4.8 S2 39.8 13.0 28.2 6.4 9.4 3.2 S3 33.3 18.5 27.0 8.1 7.7 5.4 S4 46.1 19.2 18.7 5.2 6.1 4.7

[0075] Table 5 The maximum reaction amount of minerals that can combine with carbon dioxide determined by thermogravimetric analysis

[0076]

[0077] The core sample corresponds to the reservoir test area of ​​500m 2 ×10m, the reservoir porosity is 8.3%, and the mineral components of the Shanxi Formation samples of Changqing Oilfield measured by XRD are: quartz, potassium feldspar, plagioclase, lauric zeolite, calcite and clay, as shown in Table 4. Table 5 shows the maximum reaction amount of plagioclase and clay minerals that can be combined with carbon dioxide (assuming that the main minerals react completely) based on the thermogravimetric analysis experiment. The remaining components are not calibrated because of their small amount or low degree of participation in the reaction. For example, quartz, due to its stable structural properties, the reaction conditions required for its change are more complicated. Ignoring the above minerals, the maximum reaction amount of carbon dioxide that can be combined with a single mineral is 436.4kg / m 3 (Plagioclase), 239.6kg / m 3 (clay), total 676kg / m 3 Substitute into formulas (2) to (4):

[0078]

[0079]

[0080] V i =S i ×h i ×(1-φ)×C (4);

[0081] Where:

[0082] y 长石类 =436.4;y 黏土类 =161.2+78.4=239.6; S i =500;h i =10; x 长石类 =(27.9%+28.2%+27%+18.7%) / 4=25.45%; x 黏土类 =(4.8%+3.2%+5.4%+4.7%) / 4=4.5%; C=(0.42%+0.54%+0.25%+0.17%) / 4=0.345%;

[0083] The amount of carbon dioxide buried in feldspar minerals is: 500×10×(1-8.3%)×25.45%×0.345%×436.4=1756.83kg; the amount of carbon dioxide buried in clay minerals is: 500×10×(1-8.3%)×4.5%×0.345%×239.6=170.55kg;

[0084] That is, the total amount of carbon dioxide mineral storage is: 1756.83+170.55=1927.38kg.

[0085] The characterization method provided in Example 2 of the present invention uses a thermogravimetric analyzer to calibrate the maximum reaction amount of minerals that can be combined with carbon dioxide. The volume content of various minerals in the target stratum is obtained through core slice observation, and the reaction amount of carbon dioxide of a certain mineral component in the rock per cubic meter can be roughly obtained. According to the material balance equation, a calculation model for the mineral mass change of rock minerals participating in chemical reactions is established. Assuming that all soluble minerals in the area react, the maximum reaction amount of carbon dioxide that can be combined in the test area is 1927.38 kg / m 3 .

[0086] Example 3 Quantitative Characterization of Inorganic Precipitation by CO2-Water-Rock Interaction Using Mineral Saturation Index

[0087] The test data of the aqueous solution before and after the carbon dioxide water rock reaction experiment of Example 2 are as follows:

[0088] Table 6 Mass concentration of reservoir formation water salinity before reaction

[0089]

[0090]

[0091] Table 7 Mass concentration of mineralization of reservoir formation water after reaction

[0092] Core <![CDATA[Ca 2+ (mg / L)]]> <![CDATA[Mg 2+ (mg / L)]]> <![CDATA[K + +Na + (mg / L)]]> pH S1 Water Environment <![CDATA[3.74×10 4 ]]> <![CDATA[0.20×10 4 ]]> <![CDATA[10.44×10 4 ]]> 10.97 S2 Water Environment <![CDATA[3.54×10 4 ]]> <![CDATA[0.19×10 4 ]]> <![CDATA[9.71×10 4 ]]> 9.36 S3 Water Environment <![CDATA[0.52×10 4 ]]> <![CDATA[0.09×10 4 ]]> <![CDATA[4.00×10 4 ]]> 7.82 S4 Water Environment <![CDATA[0.30×10 4 ]]> <![CDATA[0.12×10 4 ]]> <![CDATA[3.67×10 4 ]]> 7.64

[0093] Table 8 SI value and saturation state after reaction

[0094] Core SI logIAP logKsp(298K, 1atm) Reaction direction S1 Water Environment -0.11 1.39 1.50 Unsaturated state, dissolved S2 Water Environment -0.16 1.34 1.50 Unsaturated state, dissolved S3 Water Environment 2.08 3.58 1.50 Supersaturated state, precipitation S4 Water Environment -1.55 -0.05 1.50 Unsaturated state, dissolved

[0095] The mass concentration of mineralization before and after the reaction is obtained by experimental measurement. According to the mineral saturation index (SI) evaluation method of the present invention, according to the neutralization reaction principle of aqueous solution, the reaction mechanism and chemical equilibrium equation are clarified, and the SI values ​​of the four groups of samples are calculated by PHREEQC software-assisted simulation using SI=lg(IAP / Ksp), which are -0.11, -0.16, 2.08, and -1.55, respectively. According to the judgment standard of the SI value of the present invention, it can be known that the aqueous solution of S1, S2, and S4 samples is in an unsaturated state, and the mineral is about to dissolve or the mineral and the aqueous solution reach a quasi-equilibrium state; the aqueous solution of S3 sample is in an oversaturated state, and the mineral is about to precipitate or precipitation is the main reaction. This example determines the reaction mechanism (dissolution mechanism / precipitation mechanism) that occupies a dominant role by EDTA complexometric titration. and The ion activity product (IAP) and equilibrium solubility product (Ksp) are determined by combining potentiometric analysis experiments and then the mineral saturation index SI is calculated. The saturation index method can be used to determine the dissolution state of mineral components in the environmental aqueous solution, determine the direction and law of the carbon dioxide water-rock reaction, and clarify the time node for the production of inorganic carbon dioxide precipitation.

[0096] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

Claims

1. A quantitative characterization method for inorganic precipitation of carbon dioxide-water-rock interaction, characterized in that: The method comprises: S1. Select a target oil reservoir, obtain a core sample from the target oil reservoir, and collect basic physical property parameters of the target oil reservoir and the core sample; S2. Prepare formation water corresponding to the core sample, saturate the core sample with the formation water, perform a carbon dioxide-water-rock reaction in a high-temperature and high-pressure reactor, separate the reaction product into solid and liquid, and collect basic physical property parameters of the solid part and the liquid part of the reaction product respectively; S3. Based on the basic physical property parameters of the target oil reservoir, the total storage capacity of carbon dioxide in the target oil reservoir is obtained; based on the basic physical property parameters of the core sample and the basic physical property parameters of the solid part of the reaction product, the mineralized storage capacity of carbon dioxide in the target oil reservoir is obtained; based on the basic physical property parameters of the liquid part of the reaction product, the mineral saturation index is obtained, and then the inorganic precipitation of carbon dioxide-water-rock interaction is quantitatively characterized from three dimensions: the total storage capacity of carbon dioxide, the mineralized storage capacity of carbon dioxide and the mineral saturation index.

2. The quantitative characterization method for inorganic precipitation of carbon dioxide-water-rock interaction according to claim 1 is characterized in that: The basic physical property parameters of the target oil reservoir include oil reservoir area, oil reservoir thickness, reservoir porosity, oil reservoir irreducible water saturation, and density of carbon dioxide under oil reservoir conditions.

3. The quantitative characterization method for inorganic precipitation of carbon dioxide-water-rock interaction according to claim 1 is characterized in that: The basic physical property parameters of the core sample include porosity and mineral composition data, and carbon dioxide capture data of each component mineral obtained based on the mineral composition data; Preferably, the porosity of the core sample is collected using a pore-permeability tester; Preferably, the mineral composition data of the core sample is collected by XRD testing; Preferably, by performing a thermogravimetric analysis test on each constituent mineral of the core sample, the maximum reaction amount that can be combined with carbon dioxide is obtained, which is the carbon dioxide capture amount data of each constituent mineral.

4. The method for quantitative characterization of inorganic precipitation of carbon dioxide-water-rock interaction according to claim 3 is characterized in that: The basic physical property parameters of the solid part of the reaction product include porosity data; preferably, the porosity data of the solid part of the reaction product is collected using a pore-permeability tester.

5. The quantitative characterization method for inorganic precipitation of carbon dioxide-water-rock interaction according to claim 1 is characterized in that: The basic physical property parameters of the liquid part of the reaction product include ion composition data; preferably, the ion composition data of the liquid part of the reaction product is collected through EDTA complexometric titration and potentiometric analysis experiments.

6. The method for quantitative characterization of inorganic precipitation of carbon dioxide-water-rock interaction according to claim 1 is characterized in that: The parameters of the high temperature and high pressure reactor were set to a temperature of 105° C. and a pressure of 3 MPa, and the reaction time was 12 days.

7. The method for quantitative characterization of inorganic precipitation of carbon dioxide-water-rock interaction according to claim 2 is characterized in that: Based on the basic physical property parameters of the target oil reservoir, the method for obtaining the total carbon dioxide storage capacity of the target oil reservoir is to substitute the basic physical property parameters of the target oil reservoir into formula (1) for calculation: Where: M——total carbon dioxide storage, kg; ρ——density of carbon dioxide under reservoir conditions, kg / m 3 ; A——reservoir area, m 2 ; h——reservoir thickness, m; —— reservoir porosity; S w ——Immobile water saturation of the reservoir.

8. The method for quantitative characterization of inorganic precipitation of carbon dioxide-water-rock interaction according to claim 4 is characterized in that: Based on the basic physical property parameters of the core sample and the basic physical property parameters of the solid part of the reaction product, the method for obtaining the mineralized carbon dioxide storage capacity of the target reservoir is to substitute each basic physical property parameter into formulas (2) to (4) for calculation: V i =S i ×h i ×(1-φ)×C (4); Where: Q——Total carbon dioxide mineral storage in the target reservoir, kg; Q i ——Carbon dioxide capture per unit volume of type i lithology and minerals, kg; V i ——The volume of the i-th type of lithology and minerals in the target area, m 3 ; x j ——The volume percentage of the jth mineral content in the rock; y j ——Capacity of carbon dioxide captured by the jth mineral per unit volume in the rock, kg; S i ——Oil reservoir area, m 2 ; h i ——reservoir thickness, m; - porosity; C——reservoir heterogeneity coefficient.

9. The method for quantitative characterization of inorganic precipitation of carbon dioxide-water-rock interaction according to claim 5 is characterized in that: Based on the basic physical property parameters of the liquid part of the reaction product, the method for obtaining the mineral saturation index is to substitute the basic physical property parameters of the liquid part of the reaction product into formula (5) for calculation: SI = lg (IAP / Ksp) (5); Where: IAP is the product of the activities of anions and cations that make up the sparingly soluble salt in the liquid; Ksp - the solubility equilibrium constant of sparingly soluble salts.

10. Application of the quantitative characterization method according to any one of claims 1 to 9 in the evaluation of reservoir physical properties of a target oil reservoir.

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