Method and device for evaluating damage of compact oil and gas horizontal well working fluid

Abstract

The application discloses a compact oil and gas horizontal well working fluid damage condition evaluation method and device. According to the direction of the stratum layering of a reservoir to be evaluated, standard core plungers of different angles are drilled and cleaned and dried; the first permeability of water-saturated core plungers of the standard core plungers is determined; working fluid damage tests are carried out based on the angle of each water-saturated core plunger, and the second permeability of each water-saturated core plunger after damage is determined; the damage degree of the reservoir to be evaluated at each angle is determined based on the first permeability and the second permeability, and damage condition evaluation is carried out based on the damage degree. The technical scheme of the application fully considers the spatial anisotropy of reservoir damage in the horizontal well drilling process, and the damage degree of the working fluid to core plungers of different spatial orientations is evaluated, so that the reservoir damage can be accurately evaluated, and a strong theoretical basis for formulating a reasonable reservoir protection strategy is provided.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of oil and gas exploration, and particularly relates to a method and device for evaluating damage of working fluid in a tight oil and gas horizontal well. BACKGROUND

[0002] Compared with conventional oil and gas reservoirs, the geological conditions of tight oil and gas reservoirs are special, and the reservoirs are more likely to suffer from serious damage during well construction and development. The tight oil and gas reservoirs have typical multi-scale structural characteristics such as pore throat-micro-fracture-mesoscopic fracture and hydraulic fracture. The gas production process is a multi-scale gas mass transfer process. The gas seepage mechanisms in different scale seepage channels are different, and the damage mechanisms are also different. The damage mechanisms have significant spatial multi-scale characteristics.

[0003] The tight oil and gas reservoirs are usually exploited by horizontal wells. The contact area between the horizontal wellbore and the reservoir rock is greatly increased, and the angle between the wellbore and the strata bedding plane is small. Under the influence of the rock mechanical properties, the damage degree of the working fluid is different in the spatial orientation, and shows spatial anisotropy.

[0004] Therefore, it is urgent to carry out targeted reservoir damage experiment evaluation to effectively evaluate the damage of the tight oil and gas reservoirs. SUMMARY

[0005] The present application provides a method and device for evaluating damage of working fluid in a tight oil and gas horizontal well, to effectively evaluate the damage degree of the tight oil and gas reservoirs.

[0006] According to an aspect of the present application, a method for evaluating damage of working fluid in a tight oil and gas horizontal well is provided, comprising:

[0007] Drilling standard core plungers of different angles based on the direction of the strata bedding of the reservoir to be evaluated and washing and drying the standard core plungers;

[0008] Determining a first permeability of the water-saturated core plungers of the standard core plungers;

[0009] Performing working fluid damage test based on the angle of each water-saturated core plunger to determine a second permeability of each water-saturated core plunger after damage;

[0010] Determining the damage degree of the reservoir to be evaluated at each angle based on the first permeability and the second permeability, and evaluating the damage condition based on the damage degree.

[0011] Optionally, the angle includes parallel bedding and vertical bedding relative to the strata bedding and a preset angle formed with the strata bedding.

[0012] Optionally, the water-saturated core plunger is obtained by self-absorption of formation water through contact between the standard core plunger and the formation water, with the bedding plane perpendicular to the water surface.

[0013] Optionally, the first penetration rate is determined as follows:

[0014] The first permeability is calculated based on the viscosity and flow rate of the fluid used for testing, the length and cross-sectional area of ​​the saturated core plunger, and the test pressure difference across the saturated core plunger.

[0015] Optionally, the step of performing working fluid damage testing based on the angle of each saturated core plunger to determine the second permeability of the damaged saturated core plunger includes:

[0016] The water-saturated core plungers are respectively installed into the clamps at the corresponding drilling angles;

[0017] Under the same formation temperature and pressure conditions as the reservoir to be evaluated, each of the water-saturated core plungers in the holder is damaged with working fluid;

[0018] Determine the second permeability of each of the damaged water-saturated core plungers.

[0019] Optionally, the second penetration rate is determined as follows:

[0020] The second permeability is calculated based on the viscosity and flow rate of the fluid used for testing after damage, the length and cross-sectional area of ​​the saturated core plunger, and the test pressure difference across the saturated core plunger.

[0021] Optionally, the damage to each of the saturated core plungers in the holder with the working fluid includes:

[0022] The clamp is placed in a sealed environment, and working fluid is injected into the sealed environment.

[0023] The working fluid is stirred using a stirring device;

[0024] The working fluid is heated to the temperature of the reservoir to be evaluated for a preset time to cause damage.

[0025] Optionally, determining the degree of damage to the reservoir under evaluation at each of the aforementioned angles based on the first permeability and the second permeability includes:

[0026] For a water-saturated core plunger at each angle, the degree of damage is calculated using the following formula:

[0027]

[0028] Among them, R di The degree of damage at angle i; K0i The first permeability of the saturated core plunger at angle i, in units of 10i -3 μm 2 ;K di The second permeability of the saturated core plunger at angle i, in units of 10i -3 μm 2 .

[0029] Optionally, the damage assessment based on the degree of damage includes:

[0030] The directions of strong and weak damage are determined based on the damage severity standards and the degree of damage at each of the aforementioned angles;

[0031] The direction of damage is determined based on the location of strong damage and the location of weak damage.

[0032] According to another aspect of the present invention, a device for evaluating the damage of working fluid in tight oil and gas horizontal wells is provided, comprising:

[0033] The core drilling unit is used to drill standard core plungers at different angles based on the direction of the bedding of the reservoir to be evaluated, and then clean and dry them.

[0034] The first permeability determination unit is used to determine the first permeability of the water-saturated core plunger of the standard core plunger.

[0035] The second permeability determination unit is used to perform working fluid damage testing based on the angle of each saturated core plunger and determine the second permeability of each saturated core plunger after damage.

[0036] The damage degree determination unit is used to determine the degree of damage to the reservoir to be evaluated at each of the aforementioned angles based on the first permeability and the second permeability, and to evaluate the damage situation based on the degree of damage.

[0037] The technical solution of this invention involves drilling standard core plungers at different angles based on the direction of the bedding of the reservoir to be evaluated, and then washing and drying them. The first permeability of the water-saturated core plungers is determined. Based on the angle of each water-saturated core plunger, a working fluid damage test is performed to determine the second permeability of each damaged water-saturated core plunger. The degree of damage to the reservoir to be evaluated at each angle is determined based on the first and second permeabilities, and the damage is evaluated based on this degree of damage. This technical solution fully considers the spatial anisotropy of reservoir damage during horizontal well drilling. By evaluating the degree of damage to core plungers in different spatial orientations by the working fluid, reservoir damage is accurately evaluated, providing a strong theoretical basis for formulating reasonable reservoir protection strategies.

[0038] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying 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.

[0040] Figure 1 This is a flowchart of a method for evaluating the damage of working fluid in tight oil and gas horizontal wells, provided in Embodiment 1 of the present invention;

[0041] Figure 2 This is a schematic diagram of a stratum coring operation at different orientations applicable to Embodiment 1 of the present invention;

[0042] Figure 3 This is a schematic diagram of a core plunger self-absorbing formation water applicable to Embodiment 1 of the present invention;

[0043] Figure 4 This is a schematic diagram of the structure of a device for evaluating the damage of working fluid in a tight oil and gas horizontal well, provided in Embodiment 2 of the present invention. Detailed Implementation

[0044] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0045] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0046] Example 1

[0047] Figure 1 This is a flowchart of a method for evaluating the damage to working fluid in a tight oil and gas horizontal well, provided in Embodiment 1 of the present invention. This embodiment is applicable to evaluating reservoir damage in tight oil and gas horizontal wells. The method can be executed by a device for evaluating the damage to working fluid in a tight oil and gas horizontal well, which can be implemented in hardware and / or software. Figure 1 As shown, the method includes:

[0048] S110. Drill standard core plungers at different angles based on the direction of the bedding of the reservoir to be evaluated, and then clean and dry them.

[0049] Conduct well site data surveys, and based on the formation data and trajectory design of the drilling design, clarify the formation mechanical parameters and the wellbore's direction of advancement in the reservoir to ensure that subsequent experiments can accurately reflect the actual situation of the formation.

[0050] In this embodiment of the invention, the angle includes: the parallel bedding and perpendicular bedding relative to the stratigraphy, as well as the preset angle formed with the stratigraphy.

[0051] Based on the direction of the stratigraphy, a certain number of standard core plungers were drilled along parallel bedding, perpendicular bedding, and other orientations, and then washed and dried.

[0052] For example, Figure 2 This is a schematic diagram of coring a stratigraphic unit at different orientations, applicable to Embodiment 1 of the present invention. Figure 2 In the diagram, 1 represents the wellbore, 2 represents the bedding reservoir rock, and 3 represents core samples from different orientations. First, the formation mechanical parameters and the wellbore heading direction are determined. Then, core samples are drilled along the 90°, 45°, 0°, -45°, and -90° directions of the wellbore.

[0053] S120. Determine the first permeability of the water-saturated core plunger of the standard core plunger.

[0054] In this embodiment of the invention, the water-saturated core plunger is obtained by self-absorption through contact between the standard core plunger and formation water with the bedding plane perpendicular to the water surface.

[0055] Figure 3 This is a schematic diagram of a core plunger self-absorbing formation water applicable to Embodiment 1 of the present invention. Figure 3 In the diagram, 1 represents core plungers at different angles, 2 represents formation bedding planes, and 3 represents formation water. Specifically, the standard core plunger contacts the formation water with its bedding plane perpendicular to the water surface, and draws water in at its corresponding angle.

[0056] Permeability is a measure of the ability of a porous medium to allow fluid to pass through. It describes how easily a fluid flows through a porous medium under a given pressure difference. Factors such as the size, shape, distribution, and connectivity of pores in a rock significantly affect permeability. Larger pores with better connectivity generally result in higher permeability, making it easier for fluids to pass through the rock. Different mineral compositions affect the physical properties of rocks; for example, some minerals may clog pores, thus reducing permeability. The viscosity and density of fluids also influence permeability. Fluids with higher viscosity experience greater resistance in different orientations when flowing through rocks, resulting in relatively lower permeability. The initial permeability of drilled core plungers may vary, reflecting the spatial anisotropy of the reservoir. Studying the permeability of core plungers in different orientations can provide a better understanding of the spatial characteristics of reservoirs, offering a basis for formulating oil and gas extraction and reservoir protection strategies.

[0057] In this embodiment of the invention, the first permeability is determined as follows:

[0058] The first permeability is calculated based on the viscosity and flow rate of the fluid used for testing, the length and cross-sectional area of ​​the saturated core plunger, and the test pressure difference across the saturated core plunger.

[0059] Specifically, the first penetration rate can be calculated using Darcy's formula:

[0060]

[0061] Where K is the first penetration rate, in units of 10. -3 μm 2 Q represents the flow rate of the fluid used in the test, in cm³. 3 / s; μ is the viscosity of the fluid used for testing, in mPa·s; the fluid used for testing can be oil or gas; L is the length of the saturated core plunger, in cm; A is the cross-sectional area of ​​the saturated core plunger, in cm². 2 ΔP is the test pressure difference, in MPa.

[0062] S130. Based on the angle of each saturated core plunger, a working fluid damage test is performed to determine the second permeability of each saturated core plunger after damage.

[0063] In this embodiment of the invention, step S130 specifically includes:

[0064] The water-saturated core plungers are respectively installed into the clamps at the corresponding drilling angles;

[0065] Under the same formation temperature and pressure conditions as the reservoir to be evaluated, each of the water-saturated core plungers in the holder is damaged with working fluid;

[0066] Determine the second permeability of each of the damaged water-saturated core plungers.

[0067] Specifically, core plungers saturated with formation water are inserted into corresponding holders at their respective azimuths. The holder positions must strictly correspond one-to-one with the core drilling azimuths, and all core holders must be mounted on the same wellbore assembly. Under conditions identical to the formation temperature and pressure, the core plungers are simultaneously damaged with working fluid for a certain period. The damaged core plungers are then subjected to permeability testing to obtain their permeability (i.e., the second permeability).

[0068] In an embodiment of the invention, damaging each of the saturated core plungers in the holder with a working fluid includes:

[0069] The clamp is placed in a sealed environment, and working fluid is injected into the sealed environment.

[0070] The working fluid is stirred using a stirring device;

[0071] The working fluid is heated to the temperature of the reservoir to be evaluated for a preset time to cause damage.

[0072] Specifically, a water-saturated core plunger is placed in a clamp, which is a clamping device with a 360° rotation function, allowing it to rotate to the corresponding angle while clamping the core. The clamp is then placed in a sealed environment, such as a glass tank, and working fluid is added. The stirring system is turned on, and the mixture is heated to the reservoir temperature to simulate the real reservoir environment, allowing for working fluid damage for a preset time.

[0073] In this embodiment of the invention, the second permeability is determined as follows:

[0074] Determine the post-damage flow rate of each of the saturated core plungers under standard test conditions;

[0075] The second permeability is determined based on the post-damage flow rate, the size of the saturated core plunger, environmental information under the standard test conditions, and the concentration of the working fluid.

[0076] The second permeability can also be calculated using Darcy's formula. Simply replace the corresponding parameters in Darcy's formula to obtain the second permeability. Specifically, the parameter substituted into the Darcy formula mentioned above is: K is the second permeability, in units of 10. -3 μm 2 Q represents the flow rate of the fluid used in the test, in cm³. 3 / s; μ is the viscosity of the fluid used for testing, in mPa·s; L is the length of the saturated core plunger, in cm; A is the cross-sectional area of ​​the saturated core plunger, in cm². 2 ΔP is the test pressure difference, in MPa.

[0077] S140. Determine the degree of damage to the reservoir to be evaluated at each of the aforementioned angles based on the first permeability and the second permeability, and evaluate the damage situation based on the degree of damage.

[0078] In this embodiment of the invention, determining the degree of damage to the reservoir to be evaluated at each of the aforementioned angles based on the first permeability and the second permeability includes:

[0079] For a water-saturated core plunger at each angle, the degree of damage is calculated using the following formula:

[0080]

[0081] Among them, R di The degree of damage at angle i; K 0i The first permeability of the saturated core plunger at angle i, in units of 10i -3 μm 2 ;K di The second permeability of the saturated core plunger at angle i, in units of 10i -3 μm 2 .

[0082] By comparing the permeability of the core plunger before and after damage, the extent of damage to the reservoir by the working fluid can be intuitively understood. The degree of damage can be calculated to quantitatively assess the extent of damage to the reservoir.

[0083] In this embodiment of the invention, the damage assessment based on the degree of damage includes:

[0084] The directions of strong and weak damage are determined based on the damage severity standards and the degree of damage at each of the aforementioned angles;

[0085] The direction of damage is determined based on the location of strong damage and the location of weak damage.

[0086] The following detailed explanation of the solution of the present invention will be provided through a specific embodiment:

[0087] Collect the design data of a certain well, determine the formation mechanical parameters and the wellbore advance direction, and then drill downhole cores along the wellbore at 90°, 45°, 0°, -45° and -90° respectively, and number them 1, 2, 3, 4 and 5 respectively.

[0088] The core was dried and washed, and then processed according to the above embodiments. Figure 2 The method of self-absorbing formation water establishes initial water saturation.

[0089] Five core samples were placed in the core holder of the working fluid damage assessment device and rotated to the appropriate angle. Then, working fluid was added, the stirring system was turned on, and the sample was heated to the reservoir temperature to simulate the real reservoir environment.

[0090] Under the conditions of a confining pressure of 5 MPa and a pressure difference of 2 MPa, the initial flow rates Q11, Q21, Q31, Q41 and Q51 of five core samples were tested.

[0091] Three hours after the damage, the flow rates Q12, Q22, Q32, Q42 and Q52 of five core samples were tested under a confining pressure of 5 MPa and a pressure differential of 2 MPa.

[0092] The initial permeability and the permeability after damage to the core were calculated using the Darcy formula in the above embodiments.

[0093] The degree of damage to the five core samples was calculated using the formula in the above embodiment. For example, the degree of damage is shown in the table below:

[0094]

[0095] Table 1: Damage Degree of Core Plungers at Different Orientations

[0096] Table 1 shows that reservoir working fluid damage in horizontal well drilling exhibits significant spatial anisotropy. Core damage is least pronounced at 90° relative to the wellbore direction, and most severe at -90°. Furthermore, the damage rate gradually increases along the 90°, 45°, 0°, -45°, and -90° directions. Using 0° (parallel to the bedding plane) as the standard, -45° and -90° are considered strong damage azimuths, while 90° and 45° are considered weak damage azimuths.

[0097] The solutions of the embodiments of the present invention have at least the following advantages and advancements:

[0098] (1) It fully considers the spatial anisotropy of reservoir damage during horizontal well drilling. By evaluating the degree of damage to core plungers in different spatial orientations by the working fluid, reservoir damage can be accurately evaluated, providing a strong theoretical basis for formulating reasonable reservoir protection strategies.

[0099] (2) The influence of well type on reservoir damage is taken into account. Therefore, this method is also applicable to the spatial anisotropy evaluation of reservoir damage in the directional section of horizontal wells and has strong applicability.

[0100] (3) Taking into account the actual environment of the reservoir, the actual environment of the reservoir was simulated. The test results can reflect the real condition of the reservoir and have a good guiding role for engineering practice.

[0101] Example 2

[0102] Figure 4 This is a schematic diagram of the structure of a device for evaluating the damage of working fluid in a tight oil and gas horizontal well, provided in Embodiment 2 of the present invention. Figure 4 As shown, the device includes:

[0103] Core drilling unit 410 is used to drill standard core plungers at different angles based on the direction of the bedding of the reservoir to be evaluated, and then clean and dry them.

[0104] The first permeability determination unit 420 is used to determine the first permeability of the water-saturated core plunger of the standard core plunger.

[0105] The second permeability determination unit 430 is used to perform working fluid damage testing based on the angle of each saturated core plunger and determine the second permeability of each saturated core plunger after damage.

[0106] The damage degree determination unit 440 is used to determine the degree of damage to the reservoir to be evaluated at each of the angles based on the first permeability and the second permeability, and to evaluate the damage based on the degree of damage.

[0107] Optionally, the angle includes: a preset angle relative to the parallel bedding and perpendicular bedding of the stratigraphy, as well as the angle formed with the stratigraphy.

[0108] Optionally, the first permeability determination unit 420 is used to perform:

[0109] The standard core plunger is brought into contact with formation water with its bedding plane perpendicular to the water surface to generate a water-saturated core plunger.

[0110] Determine the first permeability of the water-saturated core plunger.

[0111] Optionally, the first permeability determination unit 420 is used to perform:

[0112] The first permeability is calculated based on the viscosity and flow rate of the fluid used for testing, the length and cross-sectional area of ​​the saturated core plunger, and the test pressure difference across the saturated core plunger.

[0113] Optionally, a second permeability determination unit 430 is used to perform:

[0114] The water-saturated core plungers are respectively installed into the clamps at the corresponding drilling angles;

[0115] Under the same formation temperature and pressure conditions as the reservoir to be evaluated, each of the water-saturated core plungers in the holder is damaged with working fluid;

[0116] Determine the second permeability of each of the damaged water-saturated core plungers.

[0117] Optionally, the second permeability determining unit 430 is used to determine the second permeability in the following manner:

[0118] The second permeability is calculated based on the viscosity and flow rate of the fluid used for testing after damage, the length and cross-sectional area of ​​the saturated core plunger, and the test pressure difference across the saturated core plunger.

[0119] Optionally, a second permeability determination unit 430 is used to perform:

[0120] The clamp is placed in a sealed environment, and working fluid is injected into the sealed environment.

[0121] The working fluid is stirred using a stirring device;

[0122] The working fluid is heated to the temperature of the reservoir to be evaluated for a preset time to cause damage.

[0123] Optionally, the damage determination unit 440 is used to perform:

[0124] For a water-saturated core plunger at each angle, the degree of damage is calculated using the following formula:

[0125]

[0126] Among them, R di The degree of damage at angle i; K 0i The first permeability of the saturated core plunger at angle i, in units of 10i -3 μm 2 ;K di The second permeability of the saturated core plunger at angle i, in units of 10i -3 μm 2 .

[0127] Optionally, the damage determination unit 440 is used to perform:

[0128] The directions of strong and weak damage are determined based on the damage severity standards and the degree of damage at each of the aforementioned angles;

[0129] The direction of damage is determined based on the location of strong damage and the location of weak damage.

[0130] The tight oil and gas horizontal well working fluid damage evaluation device provided in this embodiment of the invention can execute the tight oil and gas horizontal well working fluid damage evaluation method provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the execution method.

[0131] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0132] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for evaluating the damage to working fluid in tight oil and gas horizontal wells, characterized in that, include: Based on the direction of the bedding of the reservoir to be evaluated, standard core plungers at different angles are drilled, cleaned, and dried. Specifically, drilling standard core plungers at different angles involves determining the formation mechanical parameters and the wellbore advance direction, and then drilling downhole cores along the 90°, 45°, 0°, -45°, and -90° directions of the wellbore. Determine the first permeability of the water-saturated core plunger of the standard core plunger; Working fluid damage tests were conducted based on the angle of each saturated core plunger to determine the second permeability of each saturated core plunger after damage. The degree of damage to the reservoir to be evaluated at each of the aforementioned angles is determined based on the first permeability and the second permeability, and the damage situation is evaluated based on the degree of damage. The assessment of damage based on the degree of damage includes: The directions of strong and weak damage are determined based on the damage severity standards and the degree of damage at each of the aforementioned angles; The direction of damage is determined based on the location of strong damage and the location of weak damage.

2. The method according to claim 1, characterized in that, The angle includes: a preset angle relative to the bedding of the strata and the formation formed by the bedding.

3. The method according to claim 1, characterized in that, The water-saturated core plunger is obtained by self-absorption of formation water through contact between the standard core plunger and the formation water, with the bedding plane perpendicular to the water surface.

4. The method according to claim 3, characterized in that, The first penetration rate is determined as follows: The first permeability is calculated based on the viscosity and flow rate of the fluid used for testing, the length and cross-sectional area of ​​the saturated core plunger, and the test pressure difference across the saturated core plunger.

5. The method according to claim 1, characterized in that, The working fluid damage test based on the angle of each saturated core plunger, to determine the second permeability of each saturated core plunger after damage, includes: The water-saturated core plungers are respectively installed into the clamps at the corresponding drilling angles; Under the same formation temperature and pressure conditions as the reservoir to be evaluated, each of the water-saturated core plungers in the holder is damaged with working fluid; Determine the second permeability of each of the damaged water-saturated core plungers.

6. The method according to claim 5, characterized in that, The second penetration rate is determined as follows: The second permeability is calculated based on the viscosity and flow rate of the fluid used for testing after damage, the length and cross-sectional area of ​​the saturated core plunger, and the test pressure difference across the saturated core plunger.

7. The method according to claim 5, characterized in that, The method of damaging each of the saturated core plungers in the holder with working fluid includes: The clamp is placed in a sealed environment, and working fluid is injected into the sealed environment. The working fluid is stirred using a stirring device; The working fluid is heated to the temperature of the reservoir to be evaluated for a preset time to cause damage.

8. The method according to claim 1, characterized in that, The determination of the degree of damage to the reservoir under evaluation at each of the aforementioned angles based on the first permeability and the second permeability includes: For a water-saturated core plunger at each angle, the degree of damage is calculated using the following formula: ； Among them, R di The degree of damage at angle i; K 0i The first permeability of the saturated core plunger at angle i, in units of 10i -3 μm 2 ;K di The second permeability of the saturated core plunger at angle i, in units of 10i -3 μm 2 .

9. A device for evaluating the damage to working fluid in a tight oil and gas horizontal well, based on the method for evaluating the damage to working fluid in a tight oil and gas horizontal well according to any one of claims 1-8, characterized in that, include: The core drilling unit is used to determine formation mechanical parameters and wellbore advance direction. Based on the direction of the bedding of the reservoir to be evaluated, standard core plungers at different angles are drilled, cleaned, and dried. Specifically, drilling standard core plungers at different angles involves determining formation mechanical parameters and wellbore advance direction, and then drilling downhole cores along the 90°, 45°, 0°, -45°, and -90° directions of the wellbore. The first permeability determination unit is used to determine the first permeability of the water-saturated core plunger of the standard core plunger. The second permeability determination unit is used to perform working fluid damage testing based on the angle of each saturated core plunger and determine the second permeability of each saturated core plunger after damage. The damage degree determination unit is used to determine the damage degree of the reservoir to be evaluated at each of the aforementioned angles based on the first permeability and the second permeability, and to evaluate the damage situation based on the damage degree. The damage degree determination unit is used to determine the strong damage direction and the weak damage direction according to the damage degree standard and the damage degree of each angle; The direction of damage is determined based on the location of strong damage and the location of weak damage.

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