A method and apparatus for determining the rate of acid rock reaction

Abstract

The application provides an acid rock reaction rate determination method and device. The method comprises the following steps: determining the acid etching crack width of a work area based on the rock mineral composition, porosity and permeability of the work area; correcting the initial rock surface area participating in the reaction to obtain the rock surface area participating in the reaction of the work area by using the average pore diameter of the work area, the number of pores per unit area and the wall roughness coefficient of the crack formed by the reaction between the acid and the rock of the work area; determining the acid reaction volume of the work area based on the acid loss coefficient of the acid during the reaction between the acid and the rock of the work area, the reaction time between the acid and the rock of the work area and the volume of the acid injected into the work area; determining the H + diffusion coefficient of the work area based on the temperature of the reaction between the acid and the rock of the work area, the speed and concentration of the acid injected into the work area; and determining the acid rock reaction rate of the work area based on the acid etching crack width of the work area, the rock surface area participating in the reaction, the acid reaction volume, the H + diffusion coefficient of the work area, the speed and viscosity of the injected acid and the concentration gradient of the diffusion boundary layer.

Description

Technical Field

[0001] This invention belongs to the field of petroleum extraction technology, specifically relating to a method and apparatus for determining acid rock reaction rates. Background Technology

[0002] Conventional techniques for determining acid-rock reaction rates do not consider the influence of lithology and physical properties on the reaction rate. When there are significant differences in mineral composition within carbonate rocks, the reaction rate varies considerably. For example, a high content of calcite results in a faster reaction rate, while high content of argillaceous, organic, or quartz minerals leads to a slower reaction rate. Conventional techniques also fail to account for variations in the reaction area. For instance, in carbonate rocks, fractures and cavities react faster than pores. During the acid-rock reaction, as pores and fractures are dissolved, the surface area increases, leading to a faster reaction rate.

[0003] When the lithology and physical properties of the reservoir vary greatly, the results of core sampling tests on acid-rock reaction rates will also vary greatly. If a unified conventional acid-rock reaction kinetic equation is established, it will lead to inaccurate prediction of acid-rock reaction rates and inaccurate prediction of the effective distance of acid etching, which in turn will lead to deviations in the design of acidizing processes.

[0004] In conclusion, further research is still needed on technical solutions that can accurately determine the reaction rate of acid rocks. Summary of the Invention

[0005] The purpose of this invention is to provide a technical solution capable of accurately determining the acid-rock reaction rate. To achieve the above objective, this invention provides the following five technical solutions.

[0006] In a first aspect, the present invention provides a method for determining the acid-rock reaction rate, the method comprising:

[0007] Based on the rock mineral composition, porosity, and permeability of the work area, the width of the acid-etched cracks in the work area was determined.

[0008] The surface area of ​​the rock participating in the initial reaction was corrected by using the average pore diameter and the number of pores per unit area of ​​the work area, as well as the surface roughness coefficient of the cracks formed by the reaction of acid with the rock in the work area.

[0009] The acid reaction volume in the work area is determined based on the acid loss coefficient, the reaction time between the acid and the rock in the work area, and the volume of acid injected into the work area.

[0010] Based on the temperature of the acid reaction with the rocks in the work area, the rate and concentration of the acid injected into the work area, and using H... + The model determines the relationship between the diffusion coefficient and the temperature, rate, and concentration of the acid reaction with the rock in the work area H. + Diffusion coefficient;

[0011] Based on the width of the acid-etched cracks in the work area, the surface area of ​​the rock involved in the reaction in the work area, the volume of acid reaction in the work area, and the H in the work area. + The diffusion coefficient, the velocity and viscosity of the acid injected into the work area, the concentration gradient of the diffusion boundary layer in the work area, and the acid-rock reaction rate and fracture width, the surface area of ​​the rock involved in the reaction, the acid reaction volume, and H2O were all considered. + The relationship between diffusion coefficient, acid velocity and viscosity, and concentration gradient of diffusion boundary layer is used to determine the acid-rock reaction rate in the work area.

[0012] In a second aspect, the present invention provides an apparatus for determining the acid-rock reaction rate, the apparatus comprising:

[0013] Fracture Width Determination Module: Used to determine the fracture width of acid-etched fractures in the work area based on the rock mineral composition, porosity, and permeability of the work area.

[0014] The module for determining the surface area of ​​rocks participating in the reaction is used to correct the initial surface area of ​​rocks participating in the reaction by using the average pore diameter and the number of pores per unit area of ​​the work area, as well as the surface roughness coefficient of the cracks formed by the reaction of acid with the rocks in the work area. The corrected surface area of ​​rocks participating in the reaction is the surface area of ​​rocks participating in the reaction in the work area.

[0015] Acid reaction volume determination module: used to determine the acid reaction volume in the work area based on the acid filtration loss coefficient, the reaction time between the acid and the rock in the work area, and the volume of acid injected into the work area.

[0016] H + The diffusion coefficient determination module is used to determine the diffusion coefficient based on the temperature of the reaction between the acid and the rock in the work area, the rate and concentration of the acid injected into the work area, and the H+. + The model determines the relationship between the diffusion coefficient and the temperature, rate, and concentration of the acid reaction with the rock in the work area H. + Diffusion coefficient;

[0017] Acid-rock reaction rate determination module: used to determine the reaction rate based on factors such as the width of acid-etched cracks in the work area, the surface area of ​​the rock involved in the reaction, the volume of acid reaction in the work area, and the H value of the work area. + The diffusion coefficient, the velocity and viscosity of the acid injected into the work area, the concentration gradient of the diffusion boundary layer in the work area, and the acid-rock reaction rate and fracture width, the surface area of ​​the rock involved in the reaction, the acid reaction volume, and H2O were all considered. + The relationship between diffusion coefficient, acid velocity and viscosity, and concentration gradient of diffusion boundary layer is used to determine the acid-rock reaction rate in the work area.

[0018] Thirdly, the present invention 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 computer program to implement the acid-rock reaction rate determination method provided in the first aspect.

[0019] Fourthly, the present invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the acid-rock reaction rate determination method provided in the first aspect.

[0020] Fifthly, the present invention provides a computer program product comprising a computer program that, when executed by a processor, implements the acid-rock reaction rate determination method provided in the first aspect.

[0021] The technical solution provided by this invention takes into account the influence of various factors such as crack wall roughness, acid properties, rock mineral composition, and reaction temperature on the acid-rock reaction rate, and can accurately determine the acid-rock reaction rate, providing a basis for accurately analyzing the effective acid etching distance and optimizing the liquid parameters of the acid fracturing process. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings:

[0023] Figure 1 This is a graph showing the reaction rate versus temperature relationship between acid and rock.

[0024] Figure 2 This is a graph showing the relationship between acid-rock reaction rate and acid concentration.

[0025] Figure 3 This is a graph showing the relationship between acid rock reaction rate and mineral content.

[0026] Figure 4 This is a graph showing the relationship between acid-rock reaction rate and acid viscosity.

[0027] Figure 5 This is a graph showing the relationship between acid-rock reaction rate and pressure difference.

[0028] Figure 6 This is a graph showing the relationship between acid-rock reaction rate and acid flow rate. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Here, the illustrative embodiments of the present invention and their descriptions are used to explain the present invention, but are not intended to limit the present invention.

[0030] In the description of this specification, the terms "comprising," "including," "having," and "containing" are open-ended terms, meaning that they include but are not limited to. The terms "an embodiment," "a specific embodiment," "some embodiments," and "for example," etc., refer to specific features, structures, or characteristics described in connection with that embodiment or example that are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, or characteristics described can be combined in any suitable manner in one or more embodiments or examples. The order of steps involved in the various embodiments is used to illustrate the implementation of this application, and the order of steps is not limited and can be adjusted appropriately as needed.

[0031] To construct a shale composite model that is representative of actual shale, this invention proposes a method for constructing a molecular model of shale composite pore and fracture medium, a device for constructing a molecular model of shale composite pore and fracture medium, a computer device, a computer-readable storage medium, and a computer program product.

[0032] This invention provides a method for determining the acid-rock reaction rate, the method comprising the following steps:

[0033] Step 101: Determine the width of acid-etched cracks in the work area based on the rock mineral composition, porosity, and permeability of the work area.

[0034] Step 102: The surface area of ​​the rock participating in the initial reaction (i.e., the projected area of ​​the rock wall) is corrected by using the average pore diameter and the number of pores per unit area of ​​the work area, and the wall roughness coefficient of the crack formed by the reaction of acid with the rock in the work area. The corrected surface area of ​​the rock participating in the reaction is the surface area of ​​the rock participating in the reaction in the work area.

[0035] Step 103: Determine the acid reaction volume in the work area based on the acid loss coefficient, the reaction time between the acid and the rock in the work area, and the volume of acid injected into the work area.

[0036] Step 104: Based on the temperature of the acid reaction with the rock in the work area, the rate and concentration of the acid injected into the work area, determine the H+ diffusion coefficient in the work area using a model relating the H+ diffusion coefficient to the temperature, rate and concentration of the acid reaction with the rock. + Diffusion coefficient;

[0037] Step 105, based on the width of the acid-etched cracks in the work area, the surface area of ​​the rock involved in the reaction in the work area, the volume of acid reaction in the work area, and the H in the work area. +The acid-rock reaction rate in the work area was determined by using a model that relates the diffusion coefficient, the velocity and viscosity of the acid injected into the work area, the concentration gradient of the diffusion boundary layer in the work area, the acid-rock reaction rate with the fracture width, the corrected surface area of ​​the rock participating in the reaction, the acid reaction volume, the H+ diffusion coefficient, the velocity and viscosity of the acid, and the concentration gradient of the diffusion boundary layer.

[0038] Existing methods for determining acid-rock reaction rates do not consider the influence of lithology and physical properties on the reaction rate, nor do they reflect the effect of increased specific surface area due to the dissolution of pores and fissures during the acid-rock reaction process, which leads to an accelerated reaction rate. The technical solution provided by this invention considers the influence of multiple factors such as crack wall roughness, acid properties, rock mineral composition, and reaction temperature on the acid-rock reaction rate, enabling accurate determination of the acid-rock reaction rate. This provides a basis for accurately analyzing the effective acid etching distance and optimizing the liquid parameters of the acid fracturing process.

[0039] In one embodiment, step 101, determining the width of the acid-etched cracks in the work area based on the rock mineral composition, porosity, and permeability of the work area, includes:

[0040] Step 1011: Based on the rock mineral composition, porosity, and permeability of the work area, determine the fractal dimension of the fracture wall in the work area using the relationship model between the fractal dimension of the fracture wall and the rock mineral composition, porosity, and permeability.

[0041] Step 1012: Based on the fractal dimension of the crack wall in the work area, the average curvature of the acid-etched crack space in the work area is determined using the relationship model between the average curvature of the acid-etched crack space and the fractal dimension of the crack wall.

[0042] Step 1013: Based on the average curvature of the acid-etched crack space in the work area, determine the width of the acid-etched crack in the work area using the relationship model between the crack width and the average curvature of the acid-etched crack space in the work area.

[0043] In one embodiment, in step 1011, the relationship model between the fractal dimension of the fracture wall and the rock mineral composition, porosity, and permeability is as follows:

[0044]

[0045] In the formula, X i Let be the content of the i-th mineral, dimensionless; Porosity is dimensionless; K is permeability, in mD; a i b1 and b2 are coefficients; D is the fractal dimension of the crack wall, which is dimensionless.

[0046] Furthermore, the rock mineral composition includes N-1 carbonate rock minerals, X1 to X N-1 These represent the contents of these N-1 carbonate rock minerals, X NContent of non-carbonate rock minerals;

[0047] For example, the model relating the fractal dimension of the fracture wall to the rock mineral composition, porosity, and permeability is as follows:

[0048]

[0049] In the formula, X1 is the calcite content, dimensionless; X2 is the dolomite content, dimensionless; X3 is the non-carbonate rock mineral content, dimensionless. Porosity is dimensionless; K is permeability, mD; D is the fractal dimension of the crack wall, dimensionless.

[0050] In one embodiment, the relationship between the average curvature of the acid-etched crack space and the fractal dimension of the crack wall in step 1012 is as follows:

[0051] K a =mD+n

[0052] In the formula, K a denoted as the spatial mean curvature of the acid-etched crack, dimensionless; m and n are coefficients; D is the fractal dimension of the crack wall, dimensionless.

[0053] For example, the relationship between the average curvature of the acid-etched crack space and the fractal dimension of the crack wall is as follows:

[0054] K a =0.4524D-0.3937

[0055] In the formula, K a denoted as the spatial mean curvature of the acid-etched crack, dimensionless; D is the fractal dimension of the crack wall, dimensionless.

[0056] In one embodiment, the relationship model between the width of the acid-etched crack and the average curvature of the acid-etched crack space in step 1013 is as follows:

[0057] w = pK a +q

[0058] In the formula, K a denoted as the spatial mean curvature of the acid-etched crack, dimensionless; p and q are coefficients; w is the width of the acid-etched crack, dimensionless.

[0059] For example, the relationship model between the width of the acid-etched crack and the average curvature of the acid-etched crack space in the work area is as follows:

[0060] w = 8.0667K a -0.5974

[0061] In the formula, K adenoted as the spatial mean curvature of the acid-etched crack, dimensionless; D is the fractal dimension of the crack wall, dimensionless; w is the width of the acid-etched crack, in mm.

[0062] In one embodiment, in step 102, the initial surface area of ​​the rock participating in the reaction is corrected using the average pore diameter of the work area, the number of pores per unit area, and the surface roughness coefficient of the cracks formed by the reaction of acid with the rock in the work area, according to the following formula:

[0063]

[0064] In the formula, s′ is the corrected surface area of ​​the rock participating in the reaction, in cm². 2 ; s represents the initial surface area of ​​the rock participating in the reaction, in cm² 2 ;n i denoted as the number of pores per unit area of ​​the work area, dimensionless; U is the surface roughness coefficient of the cracks formed by the reaction of acid with the rock in the work area, dimensionless; d is the average pore diameter of the work area, in micrometers.

[0065] In one embodiment, in step 103, the acid reaction volume in the work area is determined by the following formula:

[0066]

[0067] In the formula, V′ is the acid reaction volume (L); V is the initial acid volume (L); and C1 is the acid loss coefficient during the reaction between the acid and the rocks in the work area. t is the reaction time (s) between the acid and the rocks in the work area.

[0068] In one embodiment, in step 103, the filtration loss coefficient of the acid during the reaction between the acid and the rock in the work area is determined based on the porosity and permeability of the work area and the number of pore volumes (i.e., the ratio of pore volume to mineral particle volume), the viscosity of the acid injected into the work area, and the pressure difference between the fractures in the work area and the formation (i.e., the difference between the bottom hole pressure and the formation pressure during construction).

[0069] Furthermore, the acid loss coefficient during the reaction between the acid and the rocks in the work area is determined using the following formula:

[0070]

[0071] In the formula, C1 is the acid loss coefficient during the reaction between the acid and the rocks in the work area. Porosity is dimensionless; K is permeability, mD; μ is acid viscosity, mPa·s; Q i Δp represents the pore volume of the work area, dimensionless; Δp represents the pressure difference between the fracture and the formation in the work area, in MPa.

[0072] In one embodiment, in step 104, H + The model relating the diffusion coefficient to the temperature, rate of reaction, and concentration of the acid in the rock reaction is as follows:

[0073]

[0074] In the formula, For H + Diffusion coefficient, m 2 / s; T is the temperature at which the acid reacts with the rock, ℃; C is the concentration of the acid injected into the work area, mol / L; u is the velocity of the acid, m / s; m1, m2, n1, n2 are coefficients;

[0075] Furthermore, H + The model relating the diffusion coefficient to the temperature, rate of reaction, and concentration of the acid in the rock reaction is as follows:

[0076]

[0077] In the formula, For H + Diffusion coefficient, m 2 / s; T is the temperature at which the acid reacts with the rock, in °C; C is the concentration of the acid, in mol / L; u is the velocity of the acid, in m / s; α, β, and γ are correction coefficients;

[0078] This preferred technical solution is commonly used in H + Based on the diffusion coefficient determination model, H + The diffusion coefficient was corrected, and the H obtained using this preferred technical solution + Using the diffusion coefficient to determine the acid-rock reaction rate yields a more accurate acid-rock reaction rate.

[0079] Furthermore, α = 0.4, γ = 10.

[0080] In one embodiment, in step 105, the acid-rock reaction rate is related to the fracture width, the surface area of ​​the rock involved in the reaction, the acid reaction volume, and H2O. + The relationship between the diffusion coefficient, the velocity and viscosity of the acid solution, and the concentration gradient of the diffusion boundary layer is modeled as follows:

[0081]

[0082] In the formula, For H + Diffusion coefficient, m 2 / s; w is the crack width, cm; u is the acid velocity, m / s; μ is the acid viscosity, mPa·s; s′ is the surface area of ​​the rock involved in the reaction, cm² 2 V′ is the volume of the acid solution in reaction, in L; K represents the concentration gradient of the diffusion boundary layer, in mol / (L·cm); K is the acid-rock reaction rate, in mol / (cm²). 2 ·s).

[0083] In one embodiment, the method further includes a data acquisition step, the data acquisition step comprising:

[0084] The study aims to obtain the rock mineral composition, porosity, permeability, average pore diameter, and number of pores per unit area of ​​the work area; the volume, concentration, viscosity, and velocity of the acid injected into the work area; and the reaction time and temperature between the acid and the rocks in the work area, the surface roughness coefficient of the cracks formed, and the initial surface area of ​​the rocks participating in the reaction.

[0085] Furthermore, the data acquisition steps include: acquiring the rock mineral composition, porosity, permeability, average pore diameter, pore volume, and number of pores per unit area of ​​the work area; acquiring the volume, concentration, viscosity, and velocity of the acid injected into the work area; acquiring the reaction time and temperature between the acid and the rocks in the work area, the surface roughness coefficient of the cracks formed, and the initial surface area of ​​the rocks participating in the reaction; and acquiring the pressure difference between the cracks in the work area and the formation.

[0086] This invention also provides an apparatus for determining the acid-rock reaction rate, as described in the following embodiments. Since the principle underlying this apparatus is similar to the method for determining the acid-rock reaction rate, its implementation can be referenced from the implementation of the method for determining the acid-rock reaction rate; repeated details will not be elaborated further.

[0087] One embodiment of the present invention provides an apparatus for determining the acid-rock reaction rate, which may specifically include:

[0088] Module 201 for determining the width of acid-etched cracks in the work area based on the rock mineral composition, porosity, and permeability of the work area.

[0089] Module 202 for determining the surface area of ​​rocks participating in the reaction: It is used to correct the initial surface area of ​​rocks participating in the reaction by using the average pore diameter of the work area, the number of pores per unit area, and the wall roughness coefficient of the cracks formed by the reaction of acid with the rocks in the work area. The corrected surface area of ​​rocks participating in the reaction is the surface area of ​​rocks participating in the reaction in the work area.

[0090] Acid reaction volume determination module 203: used to determine the acid reaction volume in the work area based on the acid loss coefficient, the reaction time between the acid and the rock in the work area, and the volume of acid injected into the work area during the reaction process.

[0091] H + The diffusion coefficient determination module is used to determine the diffusion coefficient based on the temperature of the reaction between the acid and the rock in the work area, the rate and concentration of the acid injected into the work area, and the H+.+ The model determines the relationship between the diffusion coefficient and the temperature, rate, and concentration of the acid reaction with the rock in the work area H. + Diffusion coefficient;

[0092] Acid-rock reaction rate determination module 204: used to determine the reaction rate based on the width of acid-etched cracks in the work area, the surface area of ​​the rock involved in the reaction in the work area, the volume of acid reaction in the work area, and the H in the work area. + The acid-rock reaction rate in the work area was determined by using a model that relates the diffusion coefficient, the velocity and viscosity of the acid injected into the work area, the concentration gradient of the diffusion boundary layer in the work area, the acid-rock reaction rate with the fracture width, the corrected surface area of ​​the rock participating in the reaction, the acid reaction volume, the H+ diffusion coefficient, the velocity and viscosity of the acid, and the concentration gradient of the diffusion boundary layer.

[0093] In one embodiment, the seam width determination module 201 includes:

[0094] Fractal Dimension Determination Submodule 2011: Based on the rock and mineral composition, porosity, and permeability of the work area, this module determines the fractal dimension of the fracture wall in the work area using a model that shows the relationship between the fractal dimension of the fracture wall and the rock and mineral composition, porosity, and permeability.

[0095] The average curvature determination submodule 2012 is used to determine the average curvature of the acid-etched crack space in the work area based on the fractal dimension of the crack wall surface and the relationship model between the average curvature of the acid-etched crack space and the fractal dimension of the crack wall surface.

[0096] The crack width determination submodule 2013 is used to determine the crack width of the acid-etched crack in the work area based on the average curvature of the crack space and the relationship model between the crack width and the average curvature of the crack space in the work area.

[0097] In one embodiment, the relationship between the fractal dimension of the fracture wall and the rock mineral composition, porosity, and permeability is modeled as follows:

[0098]

[0099] In the formula, X i Let be the content of the i-th mineral, dimensionless; Porosity is dimensionless; K is permeability, in mD; a i b1 and b2 are coefficients; D is the fractal dimension of the crack wall, which is dimensionless.

[0100] Furthermore, the rock mineral composition includes N-1 carbonate rock minerals, X1 to X N-1 These represent the contents of these N-1 carbonate rock minerals, X N Content of non-carbonate rock minerals;

[0101] For example, the model relating the fractal dimension of the fracture wall to the rock mineral composition, porosity, and permeability is as follows:

[0102]

[0103] In the formula, X1 is the calcite content, dimensionless; X2 is the dolomite content, dimensionless; X3 is the non-carbonate rock mineral content, dimensionless. Porosity is dimensionless; K is permeability, mD; D is the fractal dimension of the crack wall, dimensionless.

[0104] In one embodiment, the relationship between the average curvature of the acid-etched crack space and the fractal dimension of the crack wall is modeled as follows:

[0105] K a =mD+n

[0106] In the formula, K a denoted as the spatial mean curvature of the acid-etched crack, dimensionless; m and n are coefficients; D is the fractal dimension of the crack wall, dimensionless.

[0107] For example, the relationship between the average curvature of the acid-etched crack space and the fractal dimension of the crack wall is as follows:

[0108] K a =0.4524D-0.3937

[0109] In the formula, K a Let be the dimensionless average curvature of the acid-etched crack space; D be the dimensionless fractal dimension of the crack wall. In one embodiment, the relationship between the width of the acid-etched crack and the average curvature of the acid-etched crack space in the work area is modeled as follows:

[0110] w = pK a +q

[0111] In the formula, K a denoted as the spatial mean curvature of the acid-etched crack, dimensionless; p and q are coefficients; w is the width of the acid-etched crack, dimensionless.

[0112] For example, the relationship model between the width of the acid-etched crack and the average curvature of the acid-etched crack space in the work area is as follows:

[0113] w = 8.0667K a -0.5974

[0114] In the formula, K a denoted as the spatial mean curvature of the acid-etched crack, dimensionless; D is the fractal dimension of the crack wall, dimensionless; w is the width of the acid-etched crack, in mm.

[0115] In one embodiment, the rock surface area determination module 202 corrects the initial rock surface area participating in the reaction using the following formula:

[0116]

[0117] In the formula, s′ is the corrected surface area of ​​the rock participating in the reaction, in cm². 2 ; s represents the initial surface area of ​​the rock participating in the reaction, in cm² 2 ;n i denoted as the number of pores per unit area of ​​the work area, dimensionless; U is the surface roughness coefficient of the cracks formed by the reaction of acid with the rock in the work area, dimensionless; d is the average pore diameter of the work area, in micrometers.

[0118] In one embodiment, the acid reaction volume determination module 203 determines the acid reaction volume in the work area using the following formula:

[0119]

[0120] In the formula, V′ is the acid reaction volume (L); V is the initial acid volume (L); and C1 is the acid loss coefficient during the reaction between the acid and the rocks in the work area. t is the reaction time (s) between the acid and the rocks in the work area.

[0121] In one embodiment, the acid reaction volume determination module 203 is used to determine the acid loss coefficient during the reaction between the acid and the rock in the work area based on the porosity and permeability and pore volume number of the work area, the viscosity of the acid injected into the work area, and the pressure difference between the fractures in the work area and the formation.

[0122] Furthermore, the acid reaction volume determination module 203 determines the acid loss coefficient during the reaction between the acid and the rocks in the work area using the following formula:

[0123]

[0124] In the formula, C1 is the acid loss coefficient during the reaction between the acid and the rocks in the work area. Porosity is dimensionless; K is permeability, mD; μ is acid viscosity, mPa·s; Q i Δp represents the pore volume of the work area, dimensionless; Δp represents the pressure difference between the fracture and the formation in the work area, in MPa.

[0125] In one embodiment, H + The model relating the diffusion coefficient to the temperature, rate of reaction, and concentration of the acid in the rock reaction is as follows:

[0126]

[0127] In the formula, For H + Diffusion coefficient, m 2 / s; T is the temperature at which the acid reacts with the rock, in °C; C is the concentration of the acid, in mol / L; u is the velocity of the acid, in m / s; m1, m2, n1, and n2 are coefficients;

[0128] Furthermore, H + The model relating the diffusion coefficient to the temperature, rate of reaction, and concentration of the acid in the rock reaction is as follows:

[0129]

[0130] In the formula, For H + Diffusion coefficient, m 2 / s; T is the temperature at which the acid reacts with the rock, in °C; C is the concentration of the acid, in mol / L; u is the velocity of the acid, in m / s; α, β, and γ are correction coefficients;

[0131] This preferred technical solution is commonly used in H + Based on the diffusion coefficient determination model, H + The diffusion coefficient was corrected, and the H obtained using this preferred technical solution + Using the diffusion coefficient to determine the acid-rock reaction rate yields a more accurate acid-rock reaction rate.

[0132] Furthermore, α = 0.4, γ = 10.

[0133] In one embodiment, the acid-rock reaction rate is related to the fracture width, the surface area of ​​the rock involved in the reaction, the volume of the acid reaction, and H2O. + The relationship between the diffusion coefficient, the velocity and viscosity of the acid solution, and the concentration gradient of the diffusion boundary layer is modeled as follows:

[0134]

[0135] In the formula, For H + Diffusion coefficient, m 2 / s; w is the crack width, cm; u is the acid velocity, m / s; μ is the acid viscosity, mPa·s; s′ is the surface area of ​​the rock involved in the reaction, cm² 2 V′ is the volume of the acid solution in reaction, in L; K represents the concentration gradient of the diffusion boundary layer, in mol / (L·cm); K is the acid-rock reaction rate, in mol / (cm²). 2 ·s).

[0136] In one embodiment, the device further includes a data acquisition module, which is used to acquire the rock mineral composition, porosity, permeability, average pore diameter, and number of pores per unit area of ​​the work area; acquire the volume, concentration, viscosity, and velocity of the acid injected into the work area; and acquire the time and temperature of the reaction between the acid and the rock in the work area, the wall roughness coefficient of the cracks formed, and the initial surface area of ​​the rock participating in the reaction.

[0137] Furthermore, the data acquisition module is used to acquire the rock mineral composition, porosity, permeability, average pore diameter, pore volume, and number of pores per unit area of ​​the work area; acquire the volume, concentration, viscosity, and velocity of the acid injected into the work area; acquire the time and temperature of the reaction between the acid and the rocks in the work area, the surface roughness coefficient of the cracks formed, and the initial surface area of ​​the rocks participating in the reaction; and acquire the pressure difference between the cracks in the work area and the formation.

[0138] This invention also provides a computer device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the above-described method for determining the acid-rock reaction rate.

[0139] This invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method for determining the acid-rock reaction rate.

[0140] This invention also provides a computer program product, which includes a computer program that, when executed by a processor, implements the above-described method for determining the acid-rock reaction rate.

[0141] Example 1:

[0142] This embodiment provides a method for determining the acid-rock reaction rate, the method comprising:

[0143] 1. Obtain the rock mineral composition, porosity, permeability, average pore diameter, pore volume, and number of pores per unit area of ​​the work area; obtain the volume, concentration, viscosity, and velocity of the acid injected into the work area; obtain the reaction time and temperature between the acid and the rocks in the work area, the surface roughness coefficient of the fracture walls formed, and the initial surface area of ​​the rocks participating in the reaction; obtain the pressure difference between the fractures in the work area and the formation.

[0144] The results are shown in Table 1:

[0145] Table 1

[0146]

[0147]

[0148] 2. Based on the rock mineral composition, porosity, and permeability of the work area, determine the width of the acid-etched fractures in the work area; specifically including:

[0149] Based on the rock and mineral composition, porosity, and permeability of the work area, the fractal dimension of the fracture wall was determined using a model relating the fractal dimension of the fracture wall to the rock and mineral composition, porosity, and permeability. The model relating the fractal dimension of the fracture wall to the rock and mineral composition, porosity, and permeability is as follows:

[0150]

[0151] In the formula, X1 is the calcite content, dimensionless; X2 is the dolomite content, dimensionless; X3 is the non-carbonate rock mineral content, dimensionless. Porosity is dimensionless; K is permeability, mD; D is the fractal dimension of the crack wall, dimensionless.

[0152] Based on the fractal dimension of the crack wall in the work area, the average spatial curvature of the acid-etched cracks in the work area is determined using a model relating the average spatial curvature of the acid-etched cracks to the fractal dimension of the crack wall. The model relating the average spatial curvature of the acid-etched cracks to the fractal dimension of the crack wall is as follows:

[0153] K a =0.4524D-0.3937

[0154] In the formula, K a Let be the spatial mean curvature of the acid-etched crack, which is dimensionless; D is the fractal dimension of the crack wall, which is dimensionless.

[0155] Based on the average spatial curvature of the acid-etched cracks in the work area, the crack width is determined using a model relating the crack width to the average spatial curvature of the acid-etched cracks in the work area. The model relating the crack width to the average spatial curvature of the acid-etched cracks in the work area is as follows:

[0156] w = 8.0667K a -0.5974

[0157] In the formula, K a denoted as the spatial mean curvature of the acid-etched crack, dimensionless; D is the fractal dimension of the crack wall, dimensionless; w is the width of the acid-etched crack, in mm.

[0158] 3. The initial surface area of ​​the rock participating in the reaction is corrected by using the average pore diameter and the number of pores per unit area of ​​the work area, as well as the surface roughness coefficient of the cracks formed by the reaction of acid with the rock in the work area. The corrected surface area of ​​the rock participating in the reaction is obtained by using the following formula:

[0159]

[0160] In the formula, s′ is the corrected surface area of ​​the rock participating in the reaction, in cm². 2 ; s represents the initial surface area of ​​the rock participating in the reaction, in cm² 2 ;n i denoted as the number of pores per unit area of ​​the work area, dimensionless; U is the surface roughness coefficient of the cracks formed by the reaction of acid with the rock in the work area, dimensionless; d is the average pore diameter of the work area, in micrometers.

[0161] 4. Based on the porosity, permeability, and pore volume of the work area, the viscosity of the acid injected into the work area, and the relationship between the fractures and the formation in the work area, the acid loss coefficient during the reaction between the acid and the rocks in the work area is determined using the following formula:

[0162]

[0163] In the formula, C1 is the acid loss coefficient during the reaction between the acid and the rocks in the work area. Porosity is dimensionless; K is permeability, mD; μ is acid viscosity, mPa·s; Q i Δp is the pore volume of the work area, dimensionless; Δp is the pressure difference between the fracture and the formation in the work area, MPa.

[0164] Based on the acid filtration loss coefficient, the reaction time between the acid and the rock in the work area, and the volume of acid injected into the work area, the acid reaction volume in the work area is determined using the following formula:

[0165]

[0166] In the formula, V′ is the acid reaction volume (L); V is the initial acid volume (L); and C1 is the acid loss coefficient during the reaction between the acid and the rocks in the work area. t is the reaction time (s) between the acid and the rocks in the work area.

[0167] 5. Based on the temperature of the reaction between the acid and the rock in the work area, the rate and concentration of the acid injected into the work area, and using H... + The model determines the relationship between the diffusion coefficient and the temperature, rate, and concentration of the acid reaction with the rock in the work area H. + Diffusion coefficient; where H + The model relating the diffusion coefficient to the temperature, rate of reaction, and concentration of the acid in the rock reaction is as follows:

[0168]

[0169] In the formula, For H + Diffusion coefficient, m 2 / s; T is the temperature at which the acid reacts with the rock, in °C; C is the concentration of the acid, in mol / L; u is the velocity of the acid, in m / s; α, β, and γ are correction coefficients, α = 0.4, γ = 10.

[0170] 6. Based on the width of acid-etched cracks in the work area, the surface area of ​​rock involved in the reaction in the work area, the volume of acid reaction in the work area, and the H in the work area. + The diffusion coefficient, the velocity and viscosity of the acid injected into the work area, the concentration gradient of the diffusion boundary layer in the work area, and the acid-rock reaction rate and fracture width, the surface area of ​​the rock involved in the reaction, the acid reaction volume, and H2O were all considered. + A model relating diffusion coefficient, acid velocity and viscosity, and concentration gradient of the diffusion boundary layer was used to determine the acid-rock reaction rate in the work area. The acid-rock reaction rate was influenced by factors such as fracture width, surface area of ​​the reacting rock, acid reaction volume, and H₂O. + The relationship between the diffusion coefficient, the velocity and viscosity of the acid solution, and the concentration gradient of the diffusion boundary layer is modeled as follows:

[0171]

[0172] In the formula, For H + Diffusion coefficient, m 2 / s; w is the crack width, cm; u is the acid velocity, m / s; μ is the acid viscosity, mPa·s; s′ is the surface area of ​​the rock involved in the reaction, cm² 2 V′ is the volume of the acid solution in reaction, in L; K represents the concentration gradient of the diffusion boundary layer, in mol / (L·cm); K is the acid-rock reaction rate, in mol / (cm²). 2 ·s).

[0173] The results of determining the acid-rock reaction rates at different acid solution reaction temperatures with rocks in the work area are as follows: Figure 1 As shown.

[0174] To verify the accuracy of the results, the inventors used indoor experiments to determine the acid-rock reaction rate at different acid solution reaction temperatures with rocks in the work area. The results are as follows: Figure 1 As shown.

[0175] like Figure 1 As shown, the acid-rock reaction rate determined using the technical solution provided by this invention closely approximates the actual experimental data, verifying the accuracy of the technical solution provided by this invention.

[0176] Example 2

[0177] This embodiment provides a method for determining the acid-rock reaction rate. The difference between this method and Embodiment 1 is that the values ​​of the parameters obtained in step 1 are different. The results are shown in Table 2.

[0178] Table 2

[0179]

[0180]

[0181] The final results of the acid-rock reaction rate under different acid concentrations in the injection zones are as follows: Figure 2 As shown.

[0182] To verify the accuracy of the results, the inventors used indoor experiments to determine the acid-rock reaction rate under different acid concentrations in the injection areas. The results are as follows: Figure 2 As shown.

[0183] like Figure 2 As shown, the acid-rock reaction rate determined using the technical solution provided by this invention closely approximates the actual experimental data, verifying the accuracy of the technical solution provided by this invention.

[0184] Example 3

[0185] This embodiment provides a method for determining the acid-rock reaction rate. The difference between this method and Embodiment 1 is that the values ​​of the parameters obtained in step 1 are different. The results are shown in Table 3.

[0186] Table 3

[0187] physical parameters Unit symbol numerical values Temperature (°C) at which acid reacts with rocks in the work area. T 150 <![CDATA[Permeability (um 3 )]]> K 7.14 Porosity (%) Φ 0.01 Number of pores per unit area <![CDATA[n i ]]> 207.5 Time (s) for the acid to react with the rocks in the work area t 300 Volume (L) of acid injected into the work area V 0.5 The rate at which acid is injected into the work area (m / s) μ 0.25 Viscosity (mPa·s) of the acid solution injected into the work area. v 30 Pore ​​volume Qi 5.554346 Pressure difference (MPa) between the fracture and the formation in the work area △P 7 Concentration of acid solution injected into the work area (mol / L) C 5.91 Calcite content (decimal) <![CDATA[X1]]> 0.1-0.8 Dolomite content (decimal) <![CDATA[X2]]> 0.1-0.8 Non-carbonate rock mineral content (decimal) <![CDATA[X3]]> 0.1

[0188] The final results of the acid-rock reaction rates under different mineral compositions are as follows: Figure 3 As shown.

[0189] Example 4

[0190] This embodiment provides a method for determining the acid-rock reaction rate. The difference between this method and Embodiment 1 is that the values ​​of the parameters obtained in step 1 are different. The results are shown in Table 4.

[0191] Table 4

[0192] physical parameters Unit symbol numerical values Temperature (°C) at which acid reacts with rocks in the work area. T 150 <![CDATA[Permeability (um 3 )]]> K 7.14 Porosity (%) Φ 0.01 Number of pores per unit area <![CDATA[n i ]]> 207.5 Time (s) for the acid to react with the rocks in the work area t 300 Volume (L) of acid injected into the work area V 0.5 The rate at which acid is injected into the work area (m / s) μ 0.25 Viscosity (mPa·s) of the acid solution injected into the work area. v 10-100 Pore ​​volume Qi 5.554346 Pressure difference (MPa) between the fracture and the formation in the work area △P 7 Concentration of acid solution injected into the work area (mol / L) C 5.91 Calcite content (decimal) <![CDATA[X1]]> 0.7 Dolomite content (decimal) <![CDATA[X2]]> 0.2 Non-carbonate rock mineral content (decimal) <![CDATA[X3]]> 0.1

[0193] The final results of the acid-rock reaction rate under different acid viscosities in different injection zones are as follows: Figure 4 As shown.

[0194] Example 5

[0195] This embodiment provides a method for determining the acid-rock reaction rate. The difference between this method and Embodiment 1 is that the values ​​of the parameters obtained in step 1 are different. The results are shown in Table 5.

[0196] Table 5

[0197]

[0198]

[0199] The final results of the acid-rock reaction rates under the pressure difference between the fractures and the formation in different work areas are as follows: Figure 5 As shown.

[0200] Example 5

[0201] This embodiment provides a method for determining the acid-rock reaction rate. The difference between this method and Embodiment 1 is that the values ​​of the parameters obtained in step 1 are different. The results are shown in Table 6.

[0202] Table 6

[0203] physical parameters Unit symbol numerical values Temperature (°C) at which acid reacts with rocks in the work area. T 150 <![CDATA[Permeability (um 3 )]]> K 7.14 Porosity (%) Φ 0.01 Number of pores per unit area <![CDATA[n i ]]> 207.5 Time (s) for the acid to react with the rocks in the work area t 300 Volume (L) of acid injected into the work area V 0.5 The rate at which acid is injected into the work area (m / s) μ 0.05-0.5 Viscosity (mPa·s) of the acid solution injected into the work area. v 30 Pore ​​volume Qi 5.554346 Pressure difference (MPa) between the fracture and the formation in the work area △P 7 Concentration of acid solution injected into the work area (mol / L) C 5.91 Calcite content (decimal) <![CDATA[X1]]> 0.7 Dolomite content (decimal) <![CDATA[X2]]> 0.2 Non-carbonate rock mineral content (decimal) <![CDATA[X3]]> 0.1

[0204] The final results of the acid-rock reaction rate under different acid injection velocities in different injection zones are as follows: Figure 6 As shown.

[0205] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0206] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0207] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1The function specified in one or more boxes.

[0208] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0209] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for determining the reaction rate of acid-rock reactions, the method comprising: Based on the rock mineral composition, porosity, and permeability of the work area, the width of the acid-etched cracks in the work area was determined. The surface area of ​​the rock involved in the initial reaction is corrected by using the average pore diameter and the number of pores per unit area of ​​the work area, as well as the surface roughness coefficient of the cracks formed by the reaction of acid with the rock in the work area. The corrected surface area of ​​the rock involved in the reaction is the surface area of ​​the rock involved in the reaction in the work area. The acid reaction volume in the work area is determined based on the acid loss coefficient, the reaction time between the acid and the rock in the work area, and the volume of acid injected into the work area. Based on the temperature of the acid reaction with the rocks in the work area, the rate and concentration of the acid injected into the work area, and using H... + The model determines the relationship between the diffusion coefficient and the temperature, rate, and concentration of the acid reaction with the rock in the work area H. + Diffusion coefficient; Based on the width of the acid-etched cracks in the work area, the surface area of ​​the rock involved in the reaction in the work area, the volume of acid reaction in the work area, and the H in the work area. + The acid-rock reaction rate in the work area was determined by using a model that relates the diffusion coefficient, the velocity and viscosity of the acid injected into the work area, and the concentration gradient of the diffusion boundary layer in the work area. Among them, the acid-rock reaction rate is related to the fracture width, the surface area of ​​the rock involved in the reaction, the volume of acid reaction, and H. + The relationship between the diffusion coefficient, the injection rate and viscosity of the acid, and the concentration gradient of the diffusion boundary layer is modeled as follows: In the formula, For H + Diffusion coefficient, m 2 / s; w is the seam width, in cm; u The velocity of the acid solution is in m / s; μ is the viscosity of the acid solution, in mPa·s; The surface area of ​​the rock participating in the reaction, in cm² 2 ; The volume of the acid reaction solution is in liters (L). K represents the concentration gradient of the diffusion boundary layer, in mol / (L·cm); K is the acid-rock reaction rate, in mol / (cm²). 2 ·s).

2. The method according to claim 1, wherein, Based on the rock mineral composition, porosity, and permeability of the work area, the width of the acid-etched fractures in the work area was determined, including: Based on the rock mineral composition, porosity, and permeability of the work area, the fractal dimension of the fracture wall in the work area is determined by using a model relating the fractal dimension of the fracture wall to the rock mineral composition, porosity, and permeability. Based on the fractal dimension of the crack wall in the work area, the average spatial curvature of the acid-etched crack in the work area is determined by the relationship model between the average spatial curvature of the acid-etched crack and the fractal dimension of the crack wall. Based on the average curvature of the acid-etched crack space in the work area, the crack width of the acid-etched crack in the work area is determined by using a model relating the crack width to the average curvature of the acid-etched crack space in the work area.

3. The method according to claim 2, wherein, The model relating the fractal dimension of the fracture wall to the rock mineral composition, porosity, and permeability is as follows: In the formula, X i Let be the content of the i-th mineral, dimensionless; Porosity is dimensionless; K is permeability, in mD; a i b1 and b2 are coefficients; D is the fractal dimension of the crack wall, which is dimensionless.

4. The method according to claim 3, wherein, The rock mineral composition includes N-1 carbonate rock minerals, X1 to X N-1 These represent the contents of these N-1 carbonate rock minerals, X N This refers to the content of non-carbonate rock minerals.

5. The method according to claim 2, wherein, The relationship model between the average curvature of the acid-etched crack space and the fractal dimension of the crack wall is as follows: In the formula, The mean curvature of the acid-etched crack space is dimensionless. m and n are coefficients; D is the fractal dimension of the crack wall, which is dimensionless.

6. The method according to claim 2, wherein, The width of the acid-etched crack and the average curvature of the acid-etched crack space in the work area are: In the formula, is the spatial mean curvature of the acid-etched crack, dimensionless; p and q are coefficients. w represents the width of the acid-etched crack, which is dimensionless.

7. The method according to claim 1, wherein, The initial surface area of ​​the rock involved in the reaction is corrected using the average pore diameter and the number of pores per unit area of ​​the work area, as well as the surface roughness coefficient of the cracks formed by the reaction of acid with the rock in the work area, through the following formula: In the formula, To correct for the surface area of ​​the rock participating in the reaction, in cm 2 ; s The initial surface area of ​​the rock participating in the reaction, in cm² 2 ;n i The number of pores per unit area in the work area is dimensionless; U is the surface roughness coefficient of the cracks formed by the reaction of acid with the rock in the work area, which is dimensionless. The average pore diameter of the work area is in micrometers.

8. The method according to claim 1, wherein, The acid reaction volume in the work area is determined using the following formula: In the formula, The volume of the acid reaction solution is in liters (L). V C1 is the initial acid volume (L); C1 is the acid loss coefficient during the reaction between the acid and the rocks in the work area. ; The time (s) is the reaction time between the acid and the rocks in the work area.

9. The method according to claim 1, wherein, The acid loss coefficient during the reaction between the acid and the rocks in the work area is determined based on the porosity, permeability, and pore volume of the work area, the viscosity of the acid injected into the work area, and the pressure difference between the fractures in the work area and the formation.

10. The method according to claim 9, wherein, The acid loss coefficient during the reaction between the acid and the rocks in the work area is calculated using the following formula: In the formula, C1 is the acid loss coefficient during the reaction between the acid and the rocks in the work area. ; Porosity is dimensionless; K is permeability, mD; μ is acid viscosity, mPa·s. The pore volume of the work area is dimensionless. The pressure difference between the fracture and the formation in the work area is expressed in MPa.

11. The method according to claim 1, wherein, H + The model relating the diffusion coefficient to the temperature, rate of reaction, and concentration of the acid in the rock reaction is as follows: In the formula, For H + Diffusion coefficient, m 2 / s; T is the temperature at which the acid reacts with the rock, in °C; C is the concentration of the acid, in mol / L; u The velocity of the acid solution is m / s; m1, m2, n1, and n2 are coefficients.

12. The method according to claim 11, wherein, H + The model relating the diffusion coefficient to the temperature, rate of reaction, and concentration of the acid in the rock reaction is as follows: In the formula, For H + Diffusion coefficient, m 2 / s; T is the temperature at which the acid reacts with the rock, in °C; C is the concentration of the acid, in mol / L; u α represents the velocity of the acid solution, in m / s; α, β, and γ are correction coefficients.

13. The method according to claim 12, wherein, 、 、 。 14. An apparatus for determining the reaction rate of acid-rock reactions, the apparatus specifically comprising: Fracture Width Determination Module: Used to determine the fracture width of acid-etched fractures in the work area based on the rock mineral composition, porosity, and permeability of the work area. The module for determining the surface area of ​​rocks participating in the reaction is used to correct the initial surface area of ​​rocks participating in the reaction by using the average pore diameter and the number of pores per unit area of ​​the work area, as well as the surface roughness coefficient of the cracks formed by the reaction of acid with the rocks in the work area. The corrected surface area of ​​rocks participating in the reaction is the surface area of ​​rocks participating in the reaction in the work area. Acid reaction volume determination module: used to determine the acid reaction volume in the work area based on the acid filtration loss coefficient, the reaction time between the acid and the rock in the work area, and the volume of acid injected into the work area. H + The diffusion coefficient determination module is used to determine the diffusion coefficient based on the temperature of the reaction between the acid and the rock in the work area, the rate and concentration of the acid injected into the work area, and the H+. + The model determines the relationship between the diffusion coefficient and the temperature, rate, and concentration of the acid reaction with the rock in the work area H. + Diffusion coefficient; Acid-rock reaction rate determination module: used to determine the reaction rate based on factors such as the width of acid-etched cracks in the work area, the surface area of ​​the rock involved in the reaction, the volume of acid reaction in the work area, and the H value of the work area. + The acid-rock reaction rate in the work area was determined by using a model that relates the diffusion coefficient, the velocity and viscosity of the acid injected into the work area, and the concentration gradient of the diffusion boundary layer in the work area. The model relating the acid-rock reaction rate to fracture width, the surface area of ​​the rock involved in the reaction, the acid reaction volume, the H+ diffusion coefficient, the velocity and viscosity of the acid, and the concentration gradient of the diffusion boundary layer is as follows: In the formula, For H + Diffusion coefficient, m 2 / s; w is the seam width, in cm; u ρ is the velocity of the acid solution, m / s; μ is the viscosity of the acid solution, mPa·s; The surface area of ​​the rock participating in the reaction, in cm² 2 ; The volume of the acid reaction solution is in liters (L). K represents the concentration gradient of the diffusion boundary layer, in mol / (L·cm); K is the acid-rock reaction rate, in mol / (cm²). 2 ·s).

15. The apparatus according to claim 14, wherein, The seam width determination module includes: The fractal dimension determination submodule is used to determine the fractal dimension of the fracture wall in the work area based on the rock and mineral composition, porosity, and permeability of the work area, using a model that shows the relationship between the fractal dimension of the fracture wall and the rock and mineral composition, porosity, and permeability. The average curvature determination submodule is used to determine the average curvature of the acid-etched crack space in the work area based on the fractal dimension of the crack wall surface and the relationship model between the average curvature of the acid-etched crack space and the fractal dimension of the crack wall surface. The crack width determination submodule is used to determine the crack width of the acid-etched crack in the work area based on the average curvature of the crack space and the relationship model between the crack width and the average curvature of the crack space in the work area.

16. The apparatus according to claim 15, wherein, The model relating the fractal dimension of the fracture wall to the rock mineral composition, porosity, and permeability is as follows: In the formula, X i Let be the content of the i-th mineral, dimensionless; Porosity is dimensionless; K is permeability, in mD; a i b1 and b2 are coefficients.

17. The apparatus according to claim 16, wherein, The rock mineral composition includes N-1 carbonate rock minerals, X1 to X N-1 These represent the contents of these N-1 carbonate rock minerals, X N This refers to the content of non-carbonate rock minerals.

18. The apparatus according to claim 15, wherein, The relationship model between the average curvature of the acid-etched crack space and the fractal dimension of the crack wall is as follows: In the formula, The mean curvature of the acid-etched crack space is dimensionless. m and n are coefficients; D is the fractal dimension of the crack wall, which is dimensionless.

19. The apparatus according to claim 15, wherein, The width of the acid-etched crack and the average curvature of the acid-etched crack space in the work area are: In the formula, is the spatial mean curvature of the acid-etched crack, dimensionless; p and q are coefficients. w represents the width of the acid-etched crack, which is dimensionless.

20. The apparatus according to claim 14, wherein, The module for determining the surface area of ​​rocks participating in the reaction corrects the initial surface area of ​​rocks participating in the reaction using the following formula: In the formula, To correct for the surface area of ​​the rock participating in the reaction, in cm 2 ; s The initial surface area of ​​the rock participating in the reaction, in cm² 2 ;n i The number of pores per unit area in the work area is dimensionless; U is the surface roughness coefficient of the cracks formed by the reaction of acid with the rock in the work area, which is dimensionless. The average pore diameter of the work area is in micrometers.

21. The apparatus according to claim 14, wherein, The acid reaction volume determination module determines the acid reaction volume in the work area using the following formula: In the formula, The volume of the acid reaction solution is in liters (L). V C1 is the initial acid volume (L); C1 is the acid loss coefficient during the reaction between the acid and the rocks in the work area. ; The time (s) is the reaction time between the acid and the rocks in the work area.

22. The apparatus according to claim 14, wherein, The acid reaction volume determination module is used to determine the acid loss coefficient during the reaction between the acid and the rock in the work area based on the porosity, permeability, and pore volume of the work area, the viscosity of the acid injected into the work area, and the pressure difference between the fractures and the formation in the work area.

23. The apparatus according to claim 22, wherein, The acid reaction volume determination module uses the following formula to determine the acid loss coefficient during the reaction between the acid and the rocks in the work area: In the formula, C1 is the acid loss coefficient during the reaction between the acid and the rocks in the work area. ; Porosity is dimensionless; K is permeability, mD; μ is acid viscosity, mPa·s. The pore volume of the work area is dimensionless. The pressure difference between the fracture and the formation in the work area is expressed in MPa.

24. The apparatus according to claim 14, wherein, The model relating the H+ diffusion coefficient to the temperature, rate, and concentration of the acid-rock reaction is as follows: In the formula, For H + Diffusion coefficient, m 2 / s; T is the temperature at which the acid reacts with the rock, in °C; C is the concentration of the acid, in mol / L; u The velocity of the acid solution is m / s; m1, m2, n1, and n2 are coefficients.

25. The apparatus according to claim 24, wherein, The model relating the H+ diffusion coefficient to the temperature, rate, and concentration of the acid-rock reaction is as follows: In the formula, For H + Diffusion coefficient, m 2 / s; T is the temperature at which the acid reacts with the rock, in °C; C is the concentration of the acid, in mol / L; u α represents the velocity of the acid solution, in m / s; α, β, and γ are correction coefficients.

26. The apparatus according to claim 25, wherein, 、 、 。 27. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein, When the processor executes the computer program, it implements the method for determining the acid-rock reaction rate according to any one of claims 1-13.

28. A computer-readable storage medium storing a computer program that, when executed by a processor, implements the method for determining the acid-rock reaction rate according to any one of claims 1-13.

29. A computer program product comprising a computer program that, when executed by a processor, implements the method for determining the acid-rock reaction rate according to any one of claims 1-13.

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