Tight sandstone gas reservoir completion fluid adaptability evaluation method and device and storage medium

Abstract

The invention provides a tight sandstone gas reservoir completion fluid adaptability evaluation method and equipment and a storage medium, and belongs to the technical field of completion fluid displacement testing. The method comprises the following steps: preprocessing a sample rock core based on a rock core displacement experiment system; after the pretreatment is completed, based on a first preset test condition, obtaining a first steady-state displacement pressure of the sample rock core; after the duration of continuously injecting the completion fluid into the sample rock core reaches a preset duration, obtaining a second steady-state displacement pressure of the sample rock core based on a second preset test condition; and calculating seepage additional flow resistance according to the first steady-state displacement pressure and the second steady-state displacement pressure, wherein the seepage additional flow resistance is used for representing the damage degree of the completion fluid to the tight gas reservoir production layer. According to the method, the damage degree of the completion fluid can be effectively and quantitatively evaluated through the seepage additional flow resistance, the adaptability of the completion fluid is evaluated, optimization of the completion fluid in well completion operation construction is guided, and damage of the completion fluid to a tight gas reservoir production layer is prevented or reduced.

Description

Technical Field

[0001] The invention relates to the technical field of completion fluid displacement testing, and in particular to a method for evaluating the adaptability of completion fluid in tight sandstone gas reservoirs, an electronic device and a computer-readable storage medium. Background Art

[0002] The purpose of oil and gas well completion is to maximize the communication channels between production layers, so as to ensure that the oil and gas wells obtain the highest oil and gas yield. From the time a new well is drilled to the time it is officially put into production, any liquid that contacts the production layer due to operational needs is the completion fluid. The compatibility of the completion fluid system formula performance and the production layer is crucial to the oil and gas yield. It is mainly manifested in the blockage of the production layer pores caused by the solid particles in the completion fluid invading the production layer and the chemical treatment agent in the filtrate producing colloids or precipitates with the mineral components of the production layer, as well as the infiltration of the filtrate causing the clay components in the production layer to hydrate and swell, shrink the pores, and form a water lock effect, resulting in a significant decrease in the reservoir permeability and relative permeability of oil and gas, causing an additional flow resistance in the production layer compared to the normal production state, that is, damage to the production layer and affecting the yield. Therefore, completion fluid technology plays a very important role in protecting reservoirs. It can effectively evaluate the degree of damage of completion fluid to the producing layer, especially the low-pressure and low-permeability tight gas reservoirs, and provide a good guide for selecting the type and composition of completion fluid with good compatibility, so as to protect the producing layer from damage and ensure high and stable production of oil and gas wells.

[0003] At present, the commonly used evaluation method is mainly based on Darcy's law. The core flow indoor evaluation experimental method is used to evaluate the damage to oil and gas layers by measuring the change law of core permeability. It is a simulation experiment. The relevant industry standards mainly use the change of kerosene permeability of the core before and after the damage to evaluate the damage of the operating fluid to the production layer. Because the viscosity of oil is higher than that of gas, the resistance is also high, and the interaction between kerosene and rock is different from that of gas, etc., and the impact on the core seepage channels is also different. Therefore, using kerosene as the experimental medium to measure the change in core permeability will have a certain impact on low-pressure, low-permeability, tight gas reservoirs. The inappropriate selection of experimental conditions and inaccurate results will inevitably lead to errors or ambiguities in the pursuit of higher permeability recovery values ​​while ignoring the evaluation of experimental conditions and applicability. It is not very targeted and practical, and has insufficient reference value for on-site guidance. According to the Darcy formula, the permeability tested in the experiment is proportional to the liquid output and inversely proportional to the pressure difference at both ends. The pressure difference is directly generated by the displacement fluid flow rate, and the liquid phase permeability measured at different flow rates will also be different. In addition, the permeability of low-porosity and low-permeability cores is very low, and the kerosene displacement fluid flowing out per unit time is very small, resulting in large measurement errors, which in turn leads to large errors in the calculated permeability. In addition, the change in confining pressure used in the experiment will also result in different permeabilities. Summary of the invention

[0004] The purpose of the present invention is to provide a method, device and storage medium for evaluating the adaptability of completion fluid in tight sandstone gas reservoirs, so as to solve the problems of low accuracy and insufficient guiding value in existing methods for evaluating oil and gas layer damage.

[0005] In order to achieve the above object, on the one hand, the present invention provides a method for evaluating the adaptability of completion fluid in tight sandstone gas reservoirs, the method comprising:

[0006] Based on the core flooding experimental system, the sample cores are pretreated;

[0007] After the pretreatment is completed, based on the first preset test condition, a first steady-state displacement pressure of the sample core is obtained;

[0008] After the completion fluid is continuously injected into the sample core for a preset time, a second steady-state displacement pressure of the sample core is obtained based on a second preset test condition;

[0009] The additional flow resistance of seepage is calculated according to the first steady displacement pressure and the second steady displacement pressure, and the additional flow resistance of seepage is used to characterize the degree of damage of completion fluid to the production layer of tight gas reservoir.

[0010] Preferably, pre-processing the sample core includes:

[0011] Obtain the temperature and confining pressure of the sample core in real time;

[0012] When the temperature of the sample core is not equal to the preset temperature, adjusting the temperature of the sample core to the preset temperature;

[0013] When the confining pressure of the sample core is not equal to the preset pressure, the confining pressure of the sample core is adjusted to the preset pressure.

[0014] Preferably, the first preset test condition is: injecting a test fluid into the sample core along the forward end thereof;

[0015] Obtain the first steady-state displacement pressure of the sample core, including:

[0016] Obtain the injection pressure of the test fluid in real time;

[0017] Judgement i The injection pressure at time t and the i+n Whether the injection pressure is equal at all times;

[0018] In t i The injection pressure at time t and the i+n When the injection pressure at time is equal, i The injection pressure at the moment is taken as the first steady-state displacement pressure.

[0019] Preferably, the second test condition is: injecting a test fluid into the interior of the sample core along the reverse end thereof;

[0020] Obtain the second steady-state displacement pressure of the sample core, including:

[0021] Obtain the displacement pressure of the test fluid in real time;

[0022] Judgement j The displacement pressure at time t and the displacement pressure at time m j+m Whether the displacement pressure is equal at all times;

[0023] In t j The displacement pressure at time t and the displacement pressure at time m j+m When the displacement pressure at time is equal, j The displacement pressure at the moment is taken as the second steady-state displacement pressure.

[0024] Preferably, the test fluid is an inert gas.

[0025] Preferably, the direction in which the completion fluid is injected into the sample core is: injecting the completion fluid into the sample core along the forward end thereof.

[0026] Preferably, before the completion fluid is injected into the sample core, the method further comprises: preheating the completion fluid based on the core displacement experimental system.

[0027] Preferably, the components of the completion fluid include: fresh water, HEC, SAS, clay stabilizer, drainage aid, CaCO3 and NaCl.

[0028] On the other hand, the present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the above-mentioned method for evaluating the adaptability of completion fluid in tight sandstone gas reservoirs when executing the computer program.

[0029] On the other hand, the present invention further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-mentioned method for evaluating the adaptability of completion fluid in tight sandstone gas reservoirs.

[0030] Through the above technical solution, the present invention has at least the following technical effects:

[0031] The present invention can accurately measure the additional seepage flow resistance generated by tight sandstone samples before and after completion fluid invasion damage. The additional seepage flow resistance can effectively and quantitatively evaluate the degree of damage of the completion fluid, evaluate the adaptability of the completion fluid, guide the optimization of the completion fluid in the completion operation, and prevent or reduce the damage of the completion fluid to the tight gas reservoir production layer.

[0032] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following specific implementations, they are used to explain the embodiments of the present invention, but do not constitute a limitation on the embodiments of the present invention. In the accompanying drawings:

[0034] Figure 1 It is a structural block diagram of a core displacement experimental system provided by one embodiment of the present invention;

[0035] Figure 2 It is a flow chart of a method for evaluating the adaptability of completion fluid in tight sandstone gas reservoirs provided by one embodiment of the present invention;

[0036] Figure 3 The block diagram of a device for evaluating the adaptability of completion fluid in tight sandstone gas reservoirs provided by one embodiment of the present invention.

[0037] Description of Reference Numerals

[0038] 1-core holder; 2-heating unit; 3-confining pressure regulating unit; 4-completion fluid injection unit; 5-data control terminal; 6-pressure detector; 7-test fluid injection unit. DETAILED DESCRIPTION

[0039] The specific implementation of the embodiment of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the embodiment of the present invention, and is not used to limit the embodiment of the present invention.

[0040] Embodiment 1

[0041] Figure 1 is a structural block diagram of a core displacement experiment system provided by an embodiment of the present invention, such as Figure 1 As shown, the core displacement experiment system includes: a core holder 1, a heating unit 2, a confining pressure regulating unit 3, a completion fluid injection unit 4, a test fluid injection unit 7 and a data control terminal 5;

[0042] The core holder 1 is a cylindrical structure and is used to install the core. When conducting a test experiment, the obtained sample core is placed in the core holder 1.

[0043] The heating unit 2 is used to heat the core in the core holder 1, and the heating unit 2 adopts an electric heating method.

[0044] The confining pressure regulating unit 3 is used to regulate the core confining pressure in the core clamp 1. The confining pressure regulating unit 3 mainly includes: an air pump, a control valve, a pressure gauge and a gas pipeline. The output end of the air pump is connected to one end of the gas pipeline, and the other end of the gas pipeline is connected to the inside of the core clamp 1. The control valve and the pressure gauge are both installed in the gas pipeline.

[0045] The test fluid injection unit 7 is used to inject the test fluid into the core holder 1 , and the completion fluid injection unit 4 is used to inject the completion fluid into the core holder 1 .

[0046] Pressure detectors 6 are installed on the pipelines at both ends of the core holder 1. The pressure detector 6 is used to detect the confining pressure of the core holder 1, the injection pressure of the test fluid, the displacement pressure of the test fluid and the injection pressure of the completion fluid. A temperature detector is installed on the core holder 1; a temperature detector is installed on the core holder 1 to detect the temperature value of the sample core in the core holder 1.

[0047] The data control terminal 5 is used to remotely control the heating unit 2, the confining pressure regulating unit 3, the completion fluid injection unit 4 and the test fluid injection unit 7. The pressure detector 6 uploads the detected confining pressure of the core holder 1, the injection pressure of the test fluid, the displacement pressure of the test fluid and the injection pressure of the completion fluid to the data control terminal 5 for analysis and processing. The data control terminal 5 can be a smart terminal device such as a PC, a mobile phone, and a notebook.

[0048] based on Figure 1 The core displacement experimental system shown in the figure provides a method for evaluating the adaptability of completion fluid in tight sandstone gas reservoirs. Figure 2 FIG. 1 is a flow chart of a method for evaluating the adaptability of completion fluids for tight sandstone gas reservoirs provided by one embodiment of the present invention. Figure 2 As shown, the method includes:

[0049] Step S101: pre-treating the sample core based on the core displacement experiment system;

[0050] In this embodiment, before pre-processing the sample core, it is necessary to select the sample core, that is, select a well-preserved test natural core with a core specification of 25.4mm×(40-50)mm as the sample core. After selecting the sample core, the sample core is loaded into the core holder.

[0051] In this embodiment, pre-processing the sample core includes:

[0052] Step a01: obtaining the temperature of the sample core and the confining pressure of the sample core in real time;

[0053] Step a02: When the temperature of the sample core is not equal to the preset temperature, the temperature of the sample core is adjusted to the preset temperature, where the preset temperature is the simulated formation temperature required for the experiment;

[0054] Step a03: When the confining pressure of the sample core is not equal to the preset pressure, the confining pressure of the sample core is adjusted to the preset pressure.

[0055] In this embodiment, the initial temperature of the sample core is lower than the preset temperature. At this time, the sample core needs to be heated until the temperature of the sample core reaches the preset temperature; then the confining pressure of the sample core is pressurized. During the pressurization process, the temperature of the sample core may increase due to the increase in pressure; at this time, during the pressurization process, the temperature of the sample core is corrected by cooling in real time to keep the sample core at the preset temperature and reduce the test error.

[0056] In this embodiment, when adjusting the confining pressure of the sample core, it is necessary to slowly increase the confining pressure of the sample core. The preset pressure is 15 MPa. When the confining pressure of the sample core is pressurized to 15 MPa, the confining pressure is kept constant to ensure that the force on the entire core skeleton particles is in static stability and reduce test errors.

[0057] Step S102: after the preprocessing is completed, based on the first preset test condition, obtaining a first steady-state displacement pressure of the sample core;

[0058] In this embodiment, the first preset test condition is: injecting a test fluid into the sample core along the forward end thereof;

[0059] The test fluid is an inert gas, such as nitrogen, helium, etc. Nitrogen has certain inertness, is abundant in nature, and has low manufacturing cost. Nitrogen is preferably the test fluid of this embodiment.

[0060] As a further optimization of this embodiment, obtaining the first steady-state displacement pressure of the sample core includes:

[0061] Step b01: acquiring the injection pressure of the test fluid in real time. In this embodiment, a pressure detector is used to detect the injection pressure of the test fluid in real time.

[0062] Step b02: Determine t i The injection pressure at time t and the i+n Whether the injection pressure is equal at all times;

[0063] Step b03: At t i The injection pressure at time t and the i+n When the injection pressure at time is equal, i The injection pressure at the moment is taken as the first steady-state displacement pressure.

[0064] In this embodiment, nitrogen is injected into the core holder by controlling the test fluid injection unit. Nitrogen is slowly injected from one end of the sample core into the core until the nitrogen penetrates the entire sample core. The pressure detector detects the injection pressure of nitrogen in real time during the injection process. During the injection of nitrogen, the injection pressure gradually increases. After the nitrogen penetrates the sample core, the injection pressure tends to be stable and no longer increases. Therefore, when t i The injection pressure at time t and the i+n When the injection pressures at the moment are equal, that is, the injection pressures at this moment tend to be stable, the injection pressure at this moment is taken as the first steady-state displacement pressure.

[0065] In this embodiment, the value of n can be 3, that is, there is a certain t i The injection pressure at this moment is related to t i+1 Time, t i+2 Time and t i+3 The injection pressure at the moment is equal, and the injection pressure at this moment is taken as the first steady-state displacement pressure.

[0066] Step S103: after the completion fluid is continuously injected into the sample core for a preset time, a second steady-state displacement pressure of the sample core is obtained based on a second preset test condition;

[0067] After obtaining the first steady-state displacement pressure, close the control valve of the test fluid injection unit, stop injecting nitrogen into the core holder, and control the completion fluid injection unit to inject completion fluid into the sample core along the forward end thereof. The completion fluid is slowly injected from one end of the sample core into the core, and the injection pump pressure of the completion fluid injection unit is maintained at 3-4 MPa. The injection pump pressure of the present embodiment is preferably maintained at 3.5 MPa.

[0068] Secondly, before the completion fluid is injected into the sample core, the method further includes: preheating the completion fluid to 40-60°C based on the core displacement experiment system. The preheating temperature of the completion fluid in this embodiment is preferably 50°C.

[0069] After preheating the completion fluid to 50°C, the completion fluid injection unit is controlled to inject the completion fluid into the sample core along the forward end thereof. When the injection pump pressure is maintained at 3.5 MPa and the injection is continued for 20 to 40 minutes, preferably for 30 minutes, that is, the preset time of this embodiment is preferably 30 minutes. Stop injecting the completion fluid into the sample core, and at this time open the gate valve of the core holder so that the completion fluid flows out of the core holder into the collection container.

[0070] In this embodiment, the second preset test condition is: injecting a test fluid into the interior of the sample core along the reverse end thereof;

[0071] The test fluid is an inert gas, such as nitrogen, helium, etc. Nitrogen has certain inertness, is abundant in nature, and has low manufacturing cost. Nitrogen is preferably the test fluid of this embodiment.

[0072] As a further optimization of this embodiment, obtaining the second steady-state displacement pressure of the sample core includes:

[0073] Step c01: acquiring the displacement pressure of the test fluid in real time. In this embodiment, a pressure detector is used to detect the displacement pressure of the test fluid in real time.

[0074] Step c02: Determine t j The displacement pressure at time t and the displacement pressure at time m j+m Whether the displacement pressure is equal at all times;

[0075] Step c03: At t j The displacement pressure at time t and the displacement pressure at time m j+m When the displacement pressure at time is equal, j The displacement pressure at the moment is taken as the second steady-state displacement pressure.

[0076] In this embodiment, after the gate valve of the core holder is opened, nitrogen is injected into the core holder in the reverse direction by controlling the test fluid injection unit, that is, nitrogen is slowly injected into the core from the other end of the sample core, and the pressure detector detects the displacement pressure of nitrogen in the injection process in real time. During the injection of nitrogen, its displacement pressure will gradually increase, and the solid phase particles and filtrate of the completion fluid invading the core can be displaced. After the displacement is completed, the displacement pressure will tend to be stable and will no longer increase; therefore, when t j The displacement pressure at time t and the displacement pressure at time m j+m When the displacement pressures at the moment are equal, the displacement pressure tends to be stable, and the displacement pressure at this moment is taken as the second steady-state displacement pressure.

[0077] In this embodiment, the value of m can be 3, that is, there is a certain t j The injection pressure at this moment is related to t j+1 Time, t j+2 Time and t j+3 The displacement pressure at the moment is equal, and the displacement pressure at this moment is taken as the second steady-state displacement pressure.

[0078] Step S104: Calculate the additional flow resistance of seepage according to the first steady-state displacement pressure and the second steady-state displacement pressure, wherein the additional flow resistance of seepage is used to characterize the degree of damage of the completion fluid to the production layer of the tight gas reservoir.

[0079] In this embodiment, the calculation formula of the additional flow resistance of seepage is:

[0080] △P=P2-P1;

[0081] Where △P is the additional flow resistance of seepage, P2 is the second steady-state displacement pressure, and P1 is the first steady-state displacement pressure.

[0082] As a further optimization of this embodiment, the components of the completion fluid include: fresh water, HEC, SAS, clay stabilizer, drainage aid, CaCO3 and NaCl. In this embodiment, by changing the component ratio of fresh water, HEC, SAS, clay stabilizer, drainage aid, CaCO3 and NaCl, the seepage additional flow resistance of different completion fluids can be tested to evaluate the degree of damage to the tight gas reservoir production layer caused by different completion fluids.

[0083] The method for evaluating the adaptability of completion fluid for tight sandstone gas reservoirs of this embodiment can accurately measure the additional flow resistance generated by tight sandstone samples before and after completion fluid invasion damage. The additional flow resistance of seepage can effectively and quantitatively evaluate the degree of damage of completion fluid, evaluate the adaptability of completion fluid, guide the optimization of completion fluid in completion operation construction, and prevent or reduce the damage of completion fluid to the production layer of tight gas reservoir.

[0084] Embodiment 2

[0085] Figure 3 FIG. 1 is a block diagram of a device for evaluating the adaptability of completion fluids in tight sandstone gas reservoirs provided by an embodiment of the present invention. Figure 3 As shown, based on the same inventive concept as in the first embodiment, this embodiment further provides a device for evaluating the adaptability of completion fluid in a tight sandstone gas reservoir, the device being used to implement the method for evaluating the adaptability of completion fluid in a tight sandstone gas reservoir in the first embodiment, the device comprising:

[0086] A pretreatment module is used to pretreat the sample core based on the core flooding experimental system;

[0087] A first acquisition module is used to acquire a first steady-state displacement pressure of the sample core based on a first preset test condition after the preprocessing is completed;

[0088] A second acquisition module is used to acquire a second steady-state displacement pressure of the sample core based on a second preset test condition after the completion fluid is continuously injected into the sample core for a preset time.

[0089] The calculation module is used to calculate the additional flow resistance of seepage according to the first steady-state displacement pressure and the second steady-state displacement pressure, wherein the additional flow resistance of seepage is used to characterize the degree of damage of completion fluid to the production layer of tight gas reservoir.

[0090] Based on the same inventive concept as in Example 1, this embodiment further provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the above-mentioned method for evaluating the adaptability of completion fluid in tight sandstone gas reservoirs when executing the computer program.

[0091] Based on the same inventive concept as in the first embodiment, this embodiment further provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the above-mentioned method for evaluating the adaptability of completion fluid in tight sandstone gas reservoirs is implemented.

[0092] The method for evaluating the adaptability of completion fluid for tight sandstone gas reservoirs of this embodiment can accurately measure the additional flow resistance generated by tight sandstone samples before and after completion fluid invasion damage. The additional flow resistance of seepage can effectively and quantitatively evaluate the degree of damage of completion fluid, evaluate the adaptability of completion fluid, guide the optimization of completion fluid in completion operation construction, and prevent or reduce the damage of completion fluid to the production layer of tight gas reservoir.

[0093] Embodiment 3

[0094] Based on the tight sandstone gas reservoir completion fluid adaptability evaluation method of Example 1, different completion fluids were tested.

[0095] 1. Select a rock sample of a tight sandstone gas reservoir in a certain area, prepare it into a sample core with a size of 25.4mm×50mm, and mark and register it separately;

[0096] 2. Completion fluid formula to be tested:

[0097] Completion fluid A: fresh water + 0.7% HEC + 3% SAS + 1% clay stabilizer + 5% CaCO3 + 1.0% drainage aid + 5% NaCl;

[0098] Completion fluid B: fresh water + 0.7% HEC + 3% SAS + 2% clay stabilizer + 5% CaCO3 + 1.5% drainage aid + 5% NaCl;

[0099] Completion fluid C: fresh water + 0.7% HEC + 3% SAS + 3% clay stabilizer + 8% CaCO3 + 1.5% drainage agent + 5% NaCl + 5% KCl;

[0100] 3. Assemble all components of the core displacement experimental system;

[0101] 4. Correctly load the sample core into the core holder and assemble the pipeline, maintain a constant confining pressure of 15MPa, use nitrogen as the test fluid, start the system for measurement, and record the first steady-state displacement pressure P1 under the stable state;

[0102] 5. Close the nitrogen valve to release the pressure, and then use a mud pump to statically filter the preheated completion fluid A to be evaluated in the high-pressure container from the other end of the sample core. The pump pressure is maintained at 3.5MPa. After 30 minutes, stop the pump to release the pressure, and open the gate valve to allow the fluid to flow out to the collection container;

[0103] 6. Without removing the sample core, use high-pressure nitrogen to reversely displace from the other end of the sample core again, and increase the pressure until the solid particles and filtrate of the completion fluid invading the sample core are displaced. The displacement pressure gradually stabilizes, and the second steady-state displacement pressure P2 is recorded after stabilization;

[0104] 7. After the test, release the pressure, shut down the system, cool it down to room temperature, carefully take out the sample core, clean and maintain the core displacement experiment system;

[0105] 8. Test well fluids B and C according to the above steps. The test results are shown in Table 1.

[0106] Table 1

[0107]

[0108]

[0109] The test results show that, compared with completion fluid A, completion fluid B and C have increased clay stabilizer and drainage agent dosage, and its additional flow resistance △P is reduced by 0.62MPa. Compared with completion fluid B, completion fluid C further increases clay stabilizer and CaCO3 dosage, and adds 5% KCl, and its additional flow resistance △P is further reduced, which is only less than one-third of completion fluid A. It can be seen that completion fluid C has strong adaptability to the tight sandstone gas reservoir in this block and has the least damage to the production layer. This shows that evaluating and selecting completion fluids with strong adaptability has a good guiding role in preventing and reducing damage and increasing gas layer productivity during completion operations.

[0110] The present invention directly measures the additional resistance to gas seepage generated before and after the completion fluid invasion damage, quantitatively evaluates the degree of damage of the completion fluid, evaluates the adaptability of the completion fluid, guides the optimization of the completion fluid in the completion operation, and provides a scientific basis for preventing or reducing the damage of the completion fluid to the tight gas reservoir and improving the gas production rate.

[0111] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0112] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0113] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0114] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0115] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0116] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0117] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0118] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0119] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

Claims

1. A method for evaluating the adaptability of completion fluid in tight sandstone gas reservoirs, characterized in that: The method comprises: Based on the core flooding experimental system, the sample cores are pretreated; After the pretreatment is completed, based on the first preset test condition, a first steady-state displacement pressure of the sample core is obtained; After the completion fluid is continuously injected into the sample core for a preset time, a second steady-state displacement pressure of the sample core is obtained based on a second preset test condition; The additional flow resistance of seepage is calculated according to the first steady displacement pressure and the second steady displacement pressure, and the additional flow resistance of seepage is used to characterize the degree of damage of completion fluid to the production layer of tight gas reservoir.

2. The method according to claim 1, characterized in that: Pre-treatment of sample cores includes: Obtain the temperature and confining pressure of the sample core in real time; When the temperature of the sample core is not equal to the preset temperature, adjusting the temperature of the sample core to the preset temperature; When the confining pressure of the sample core is not equal to the preset pressure, the confining pressure of the sample core is adjusted to the preset pressure.

3. The method according to claim 1, characterized in that The first preset test condition is: injecting a test fluid into the sample core along the forward end thereof; Obtain the first steady-state displacement pressure of the sample core, including: Obtain the injection pressure of the test fluid in real time; Judgement i The injection pressure at time t and the i+n Whether the injection pressure is equal at all times; In t i The injection pressure at time t and the i+n When the injection pressure at time is equal, i The injection pressure at the moment is taken as the first steady-state displacement pressure.

4. The method according to claim 1, characterized in that The second test condition is: injecting a test fluid into the sample core along the reverse end thereof; Obtain the second steady-state displacement pressure of the sample core, including: Obtain the displacement pressure of the test fluid in real time; Judgement j The displacement pressure at time t and the displacement pressure at time m j+m Whether the displacement pressure is equal at all times; In t j The displacement pressure at time t and the displacement pressure at time m j+m When the displacement pressure at time is equal, j The displacement pressure at the moment is taken as the second steady-state displacement pressure.

5. The method according to claim 3 or 4, characterized in that: The test fluid is an inert gas.

6. The method according to claim 1, characterized in that The direction in which the completion fluid is injected into the sample core is: injecting the completion fluid into the sample core along the positive end thereof.

7. The method according to claim 1, characterized in that Before the completion fluid is injected into the sample core, the method further includes: preheating the completion fluid based on the core displacement experimental system.

8. The method according to claim 6 or 7, characterized in that: The components of the completion fluid include: fresh water, HEC, SAS, clay stabilizer, drainage agent, CaCO3 and NaCl.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method for evaluating the adaptability of completion fluid for tight sandstone gas reservoirs according to any one of claims 1 to 8 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method for evaluating the adaptability of completion fluid for tight sandstone gas reservoirs according to any one of claims 1 to 8 is implemented.

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