Method, device and equipment for predicting reservoir damage of low-permeability and ultra-low-permeability oil reservoir and medium

Abstract

The invention discloses a reservoir damage prediction method, device and equipment for a low-permeability and ultra-low-permeability reservoir and a medium. The method comprises the following steps: selecting a target reservoir core, and determining the initial permeability of the core under a simulated formation condition; a core permeability test is continuously conducted on the target reservoir core, liquid for the test is injected for soaking, at least one set of core permeability data is obtained, and each set of core permeability data comprises a time value and the core permeability under the time value; drawing a rock core permeability change curve based on the rock core initial permeability and the rock core permeability data, wherein the rock core permeability change curve represents the change condition of the rock core permeability along with time; and performing numerical simulation on the rock core permeability change curve to predict the long-term damage condition of the reservoir. According to the scheme provided by the invention, the long-term damage to the reservoir and the yield after fracturing can be predicted by means of long-term core permeability measurement test and numerical simulation on the obtained long-term core permeability change condition.

Description

Technical Field

[0001] The invention relates to the technical field of reservoir protection, and in particular to a method, device, equipment and medium for predicting reservoir damage in a low-permeability or extra-low-permeability oil reservoir. Background Art

[0002] As the development of crude oil resources in my country continues, the development of low-permeability and extra-low-permeability oil reservoirs with greater potential reserves has attracted increasing attention. Due to the low porosity and low permeability of low-permeability and extra-low-permeability oil reservoirs, the development is difficult. Currently, the development of low-permeability and extra-low-permeability oil reservoirs mainly adopts fracturing. After fracturing, the initial production increases rapidly, but with the increase of time, the production decreases significantly, and there is little concern about the long-term damage to the reservoir after fracturing.

[0003] At present, the prediction of reservoir damage is to measure the effect of different injected fluids on core permeability through core flow tests, and further predict the degree of core damage and increased production and injection. However, this method does not measure the long-term permeability changes and cannot truly reflect the damage of the reservoir.

[0004] In summary, a method is needed to reflect the actual reservoir damage situation of low-permeability and ultra-low-permeability oil reservoirs. Summary of the invention

[0005] The present invention provides a method, device, equipment and medium for predicting reservoir damage in a low-permeability and extra-low-permeability oil reservoir, which can reflect the actual reservoir damage situation of the low-permeability and extra-low-permeability oil reservoir.

[0006] According to one aspect of the present invention, a method for predicting reservoir damage in a low-permeability or ultra-low-permeability oil reservoir is provided, comprising:

[0007] Select the target reservoir core and determine the initial permeability of the core under simulated formation conditions;

[0008] Continuously conducting a core permeability test on the target reservoir core and injecting an experimental liquid for soaking to obtain at least one set of core permeability data, wherein each set of core permeability data includes a time value and a core permeability at the time value;

[0009] Based on the initial permeability of the core and the permeability data of the core, a core permeability variation curve is drawn, wherein the core permeability variation curve represents the variation of the core permeability over time;

[0010] The core permeability variation curve is numerically simulated to predict the long-term damage of the reservoir.

[0011] Optionally, the core permeability test includes: a core flow test, a static imbibition test and / or a core immersion test.

[0012] Optionally, the injected experimental liquid includes: gel breaking liquid, slick water and fracturing fluid; accordingly, the core permeability test is continuously performed on the target reservoir core and the experimental liquid is injected for soaking to obtain at least one set of core permeability data, including:

[0013] The test pressure and temperature were maintained, and core permeability, porosity and throat changes were measured on the 1st, 3rd, 7th, 14th, 20th, 60th, 90th and 180th days to obtain core permeability data corresponding to the days.

[0014] Optionally, drawing a core permeability change curve based on the core initial permeability and the core permeability data includes:

[0015] Taking the initial permeability of the core as the core permeability data corresponding to the initial time;

[0016] Draw an initial core permeability change curve based on the core permeability data corresponding to the initial time and the core permeability data corresponding to the number of days;

[0017] The initially drawn core permeability change curve is fitted and corrected according to the porosity and / or throat changes to obtain the core permeability change curve, wherein the porosity and / or throat changes are determined by nuclear magnetic resonance or CT scanning.

[0018] Optionally, performing fitting correction on the initially drawn core permeability change curve according to the porosity and / or throat change to obtain the core permeability change curve includes:

[0019] The initially drawn core permeability variation curve is fitted and corrected according to a first formula, wherein the first formula includes:

[0020]

[0021] Where K is the core permeability, φ is the porosity; T 2g is the geometric mean of the T2 spectrum; C is the coefficient to be determined.

[0022] Optionally, fitting and correcting the initially drawn core permeability change curve according to the porosity and / or throat change to obtain the core permeability change curve includes:

[0023] The initially drawn core permeability variation curve is fitted and corrected according to a second formula, wherein the second formula includes:

[0024]

[0025] Where K is permeability; φ is porosity; Rpt is the pore-throat ratio; r p is the pore radius, um; τ is the ratio of the actual pore length to the apparent length of the core.

[0026] Optionally, the performing of numerical simulation on the core permeability variation curve to predict long-term reservoir damage includes:

[0027] Importing the core permeability variation curve into a preset numerical simulation software;

[0028] In the numerical simulation software, the core permeability change curve is fitted and corrected with the historical production output results to predict the long-term damage to the reservoir and the output after fracturing.

[0029] According to another aspect of the present invention, a device for predicting reservoir damage in a low-permeability or ultra-low-permeability oil reservoir is provided, comprising:

[0030] The initial permeability determination unit is used to select the target reservoir core and determine the initial permeability of the core under simulated formation conditions;

[0031] A core permeability data determination unit, used for continuously performing a core permeability test on the target reservoir core and injecting an experimental liquid for soaking to obtain at least one set of core permeability data, wherein each set of core permeability data includes a time value and a core permeability at the time value;

[0032] A change curve drawing unit, used for drawing a core permeability change curve based on the core initial permeability and the core permeability data, wherein the core permeability change curve represents the change of the core permeability over time;

[0033] The numerical simulation unit is used to perform numerical simulation on the core permeability variation curve to predict the long-term damage of the reservoir.

[0034] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising:

[0035] At least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the method for predicting reservoir damage in low-permeability and ultra-low-permeability oil reservoirs described in any embodiment of the present invention.

[0036] According to another aspect of the present invention, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the method for predicting reservoir damage in a low-permeability or ultra-low-permeability oil reservoir as described in any embodiment of the present invention when executed.

[0037] The technical solution of the embodiment of the present invention is to select a target reservoir core and determine the initial permeability of the core under simulated formation conditions; continuously perform core permeability tests on the target reservoir core and inject experimental liquid for immersion to obtain at least one set of core permeability data, wherein each set of core permeability data includes a time value and the core permeability at the time value; draw a core permeability change curve based on the initial core permeability and the core permeability data, and the core permeability change curve represents the change of core permeability over time; perform numerical simulation on the core permeability change curve to predict long-term reservoir damage. The solution of the present invention can predict the long-term damage and production of the reservoir after fracturing through long-term core permeability measurement tests and by using numerical simulation methods for the obtained long-term core permeability changes, and guide the reservoir protection technology of low-permeability and ultra-low-permeability oil reservoirs.

[0038] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0040] Figure 1 This is a flow chart of a method for predicting reservoir damage in a low-permeability or ultra-low-permeability oil reservoir provided in Example 1 of the present invention;

[0041] Figure 2 It is a schematic diagram of a core permeability variation curve applicable to the first embodiment of the present invention;

[0042] Figure 3 It is a schematic diagram of the structure of a low-permeability and ultra-low-permeability reservoir damage prediction device provided by the second embodiment of the present invention;

[0043] Figure 4 It is a structural schematic diagram of an electronic device for implementing the method for predicting reservoir damage of a low-permeability or ultra-low-permeability oil reservoir according to an embodiment of the present invention. DETAILED DESCRIPTION

[0044] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work 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 and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0046] With the continuous development of crude oil resources in my country, the exploitation of low-permeability and extra-low-permeability oil reservoirs with greater potential reserves has attracted increasing attention. Due to the low porosity and permeability of low-permeability and extra-low-permeability oil reservoirs, the exploitation is difficult. At present, the exploitation of low-permeability and extra-low-permeability oil reservoirs mainly adopts the means of fracturing. The initial production increases rapidly after fracturing, and the production decreases significantly with time, and there is little attention paid to the long-term damage to the reservoir after fracturing. Therefore, by measuring the change of core permeability of low-permeability and extra-low-permeability oil reservoirs over time, the long-term damage and production of the reservoir after fracturing can be predicted by numerical simulation. Due to the low porosity and low permeability of low-permeability and extra-low-permeability oil reservoirs, the long-term measurement method of core permeability becomes the key. Therefore, studying the long-term measurement method of core permeability and using numerical simulation are the top priorities for predicting the long-term damage to the reservoir and production after fracturing.

[0047] Due to the low porosity and low permeability of low-permeability and extra-low permeability reservoirs, the exploitation is difficult. At present, the exploitation of low-permeability and extra-low permeability reservoirs mainly adopts fracturing. The initial production increases rapidly after fracturing, but decreases significantly with time, and there is little concern about the long-term damage to the reservoir after fracturing. Therefore, by measuring the change of core permeability of low-permeability and extra-low permeability reservoirs over time, numerical simulation can be used to predict the long-term damage and production of the reservoir after fracturing.

[0048] Embodiment 1

[0049] Figure 1This is a flowchart of a method for predicting reservoir damage in a low-permeability or extra-low-permeability oil reservoir provided in Example 1 of the present invention. This embodiment is applicable to the case of predicting long-term reservoir damage after fracturing of a low-permeability or extra-low-permeability oil reservoir. This method can be performed by a low-permeability or extra-low-permeability oil reservoir reservoir damage prediction device. The low-permeability or extra-low-permeability oil reservoir reservoir damage prediction device can be implemented in the form of hardware and / or software. The low-permeability or extra-low-permeability oil reservoir reservoir damage prediction device can be configured in an electronic device. Figure 1 As shown, the method includes:

[0050] S110. Select a target reservoir core and determine the initial permeability of the core under simulated formation conditions.

[0051] Among them, the core selection is consistent with the formation, and the simulated formation conditions are the same as the actual formation conditions.

[0052] S120, continuously conducting a core permeability test on the target reservoir core and injecting experimental liquid for immersion to obtain at least one set of core permeability data, wherein each set of core permeability data includes a time value and a core permeability at the time value.

[0053] In the embodiment of the present invention, the core permeability test includes: a core flow test, a static imbibition test and / or a core immersion test.

[0054] In the embodiment of the present invention, the liquid for injection experiment includes: gel breaking liquid, slippery water and fracturing fluid;

[0055] Accordingly, the target reservoir core is continuously subjected to a core permeability test and is soaked with an experimental liquid to obtain at least one set of core permeability data, including:

[0056] The test pressure and temperature were maintained, and core permeability, porosity and throat changes were measured on the 1st, 3rd, 7th, 14th, 20th, 60th, 90th and 180th days to obtain core permeability data corresponding to the days.

[0057] Among them, the long-term core permeability measurement test includes core flow test, static imbibition test and core immersion test; the injected liquids include degelling liquid, slick water and fracturing fluid.

[0058] S130. Draw a core permeability variation curve based on the core initial permeability and the core permeability data, wherein the core permeability variation curve represents the variation of the core permeability over time.

[0059] In an embodiment of the present invention, the step of drawing a core permeability variation curve based on the core initial permeability and the core permeability data includes:

[0060] Taking the initial permeability of the core as the core permeability data corresponding to the initial time;

[0061] Draw an initial core permeability change curve based on the core permeability data corresponding to the initial time and the core permeability data corresponding to the number of days;

[0062] The initially drawn core permeability change curve is fitted and corrected according to the porosity and / or throat changes to obtain the core permeability change curve, wherein the porosity and / or throat changes are determined by nuclear magnetic resonance or CT scanning.

[0063] Among them, nuclear magnetic resonance and CT scanning technology are considered to be a relatively accurate means of describing pore characteristics and determining fluid distribution, and have been maturely applied in the oil and gas industry. Nuclear magnetic resonance can be used to scan the core T2 spectrum, analyze the pore size changes before and after reservoir fracturing, and clarify the extent of reservoir damage.

[0064] In an embodiment of the present invention, the fitting correction of the initially drawn core permeability change curve according to the porosity and / or throat change to obtain the core permeability change curve includes:

[0065] The initially drawn core permeability variation curve is fitted and corrected according to a first formula, wherein the first formula includes:

[0066]

[0067] Where K is the core permeability, φ is the porosity; T 2g is the geometric mean of the nuclear magnetic resonance T2 spectrum; C is the coefficient to be determined.

[0068] In an embodiment of the present invention, fitting and correcting the initially drawn core permeability change curve according to the porosity and / or throat change to obtain the core permeability change curve includes:

[0069] The initially drawn core permeability variation curve is fitted and corrected according to a second formula, wherein the second formula includes:

[0070]

[0071] Where K is permeability; φ is porosity; R pt is the pore-throat ratio; r p is the pore radius, um; τ is the ratio of the actual pore length to the apparent length of the core.

[0072] In the specific experiment, the target formation core was selected to simulate the formation conditions, and the initial permeability of the core was measured and recorded as the core permeability at day 0. A long-term core flow model test was carried out on the core. According to the on-site process, 3PV of slick water, 3PV of fracturing fluid, and 4PV of degelling fluid were injected in sequence. The test pressure and temperature were maintained, and core permeability, porosity, and throat changes were measured using nuclear magnetic resonance and CT scanning at 1d, 3d, 7d, 14d, 20d, 60d, 90d, and 180d. The measured core permeability was recorded, and combined with the changes in the core porosity and throat, the first formula and the second formula were used to fit and correct the curve of the core permeability change over time. A core permeability change curve such as Figure 2 shown.

[0073] S140, performing numerical simulation on the core permeability variation curve to predict long-term reservoir damage.

[0074] In an embodiment of the present invention, the numerical simulation of the core permeability change curve to predict the long-term damage of the reservoir includes:

[0075] Importing the core permeability variation curve into a preset numerical simulation software;

[0076] In the numerical simulation software, the core permeability change curve is fitted and corrected with the historical production output results to predict the long-term damage to the reservoir and the output after fracturing.

[0077] Among them, according to the curve of core permeability change over time, numerical simulation software such as CMG is used to import the change of core permeability over 180 days to predict the long-term damage to the reservoir and production after fracturing. By importing the curve of core permeability change over time and fitting and correcting it with the historical production results, the long-term damage to the reservoir and production after fracturing are predicted.

[0078] The long-term core permeability measurement test of the embodiment of the present invention and the method for predicting the long-term damage to the reservoir and the output after fracturing by means of numerical simulation of the obtained long-term core permeability changes can be used for the application of reservoir protection technology for low-permeability and extra-low-permeability oil reservoirs, can predict the long-term damage to the reservoir and the output after fracturing, and guide the reservoir protection technology for low-permeability and extra-low-permeability oil reservoirs.

[0079] Embodiment 2

[0080] Figure 3 Schematic diagram of the structure of a low-permeability and ultra-low-permeability reservoir damage prediction device provided by the second embodiment of the present invention. Figure 3 As shown, the device comprises:

[0081] The initial permeability determination unit 310 is used to select a target reservoir core and determine the initial permeability of the core under simulated formation conditions;

[0082] The core permeability data determination unit 320 is used to continuously perform a core permeability test on the target reservoir core and inject an experimental liquid for soaking to obtain at least one set of core permeability data, wherein each set of core permeability data includes a time value and a core permeability at the time value;

[0083] A change curve drawing unit 330 is used to draw a core permeability change curve based on the core initial permeability and the core permeability data, wherein the core permeability change curve represents the change of the core permeability over time;

[0084] The numerical simulation unit 340 is used to perform numerical simulation on the core permeability variation curve to predict the long-term damage of the reservoir.

[0085] Optionally, the core permeability test includes: a core flow test, a static imbibition test and / or a core immersion test.

[0086] Optionally, the liquid used for the injection experiment includes: gel breaking liquid, slippery water and fracturing fluid;

[0087] Accordingly, the core permeability data determining unit 320, when performing the core permeability test on the target reservoir core continuously and injecting the experimental liquid for immersion to obtain at least one set of core permeability data, specifically performs:

[0088] The test pressure and temperature were maintained, and core permeability, porosity and throat changes were measured on the 1st, 3rd, 7th, 14th, 20th, 60th, 90th and 180th days to obtain core permeability data corresponding to the days.

[0089] Optionally, the change curve drawing unit 330 is used to execute: drawing the core permeability change curve based on the core initial permeability and the core permeability data includes:

[0090] Taking the initial permeability of the core as the core permeability data corresponding to the initial time;

[0091] Draw an initial core permeability change curve based on the core permeability data corresponding to the initial time and the core permeability data corresponding to the number of days;

[0092] The initially drawn core permeability change curve is fitted and corrected according to the porosity and / or throat changes to obtain the core permeability change curve, wherein the porosity and / or throat changes are determined by nuclear magnetic resonance or CT scanning.

[0093] Optionally, the change curve drawing unit 330, when performing the fitting correction on the initially drawn core permeability change curve according to the porosity and / or throat change to obtain the core permeability change curve, specifically performs:

[0094] The initially drawn core permeability variation curve is fitted and corrected according to a first formula, wherein the first formula includes:

[0095]

[0096] Where K is the core permeability, φ is the porosity; T 2g is the geometric mean of the nuclear magnetic resonance T2 spectrum; C is the coefficient to be determined.

[0097] Optionally, the change curve drawing unit 330, when performing the fitting correction on the initially drawn core permeability change curve according to the porosity and / or throat change to obtain the core permeability change curve, specifically performs:

[0098] The initially drawn core permeability variation curve is fitted and corrected according to a second formula, wherein the second formula includes:

[0099]

[0100] Where K is permeability; φ is porosity; R pt is the pore-throat ratio; r p is the pore radius, um; τ is the ratio of the actual pore length to the apparent length of the core.

[0101] Optionally, the numerical simulation unit 340 is used to perform:

[0102] Importing the core permeability variation curve into a preset numerical simulation software;

[0103] In the numerical simulation software, the core permeability change curve is fitted and corrected with the historical production output results to predict the long-term damage to the reservoir and the output after fracturing.

[0104] The low-permeability and extra-low-permeability reservoir damage prediction device provided in the embodiment of the present invention can execute the low-permeability and extra-low-permeability reservoir damage prediction method provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the execution method.

[0105] Embodiment 3

[0106] Figure 4A schematic diagram of the structure of an electronic device 10 that can be used to implement an embodiment of the present invention is shown. The electronic device is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices (such as helmets, glasses, watches, etc.) and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or required herein.

[0107] like Figure 4 As shown, the electronic device 10 includes at least one processor 11, and a memory connected to the at least one processor 11, such as a read-only memory (ROM) 12, a random access memory (RAM) 13, etc., wherein the memory stores a computer program that can be executed by at least one processor, and the processor 11 can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 12 or the computer program loaded from the storage unit 18 to the random access memory (RAM) 13. In the RAM 13, various programs and data required for the operation of the electronic device 10 can also be stored. The processor 11, the ROM 12, and the RAM 13 are connected to each other through a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0108] A number of components in the electronic device 10 are connected to the I / O interface 15, including: an input unit 16, such as a keyboard, a mouse, etc.; an output unit 17, such as various types of displays, speakers, etc.; a storage unit 18, such as a disk, an optical disk, etc.; and a communication unit 19, such as a network card, a modem, a wireless communication transceiver, etc. The communication unit 19 allows the electronic device 10 to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks.

[0109] The processor 11 may be a variety of general and / or special processing components with processing and computing capabilities. Some examples of the processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processor 11 executes the various methods and processes described above, such as a method for predicting reservoir damage in a low-permeability and ultra-low-permeability oil reservoir.

[0110] In some embodiments, the low permeability and extra-low permeability reservoir formation damage prediction method can be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as a storage unit 18. In some embodiments, part or all of the computer program can be loaded and / or installed on the electronic device 10 via the ROM 12 and / or the communication unit 19. When the computer program is loaded into the RAM 13 and executed by the processor 11, one or more steps of the low permeability and extra-low permeability reservoir formation damage prediction method described above can be performed. Alternatively, in other embodiments, the processor 11 can be configured to execute the low permeability and extra-low permeability reservoir formation damage prediction method by any other appropriate means (for example, by means of firmware).

[0111] Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0112] Computer programs for implementing the methods of the present invention may be written in any combination of one or more programming languages. These computer programs may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that when the computer program is executed by the processor, the functions / operations specified in the flow chart and / or block diagram are implemented. The computer program may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

[0113] In the context of the present invention, a computer-readable storage medium may be a tangible medium that may contain or store a computer program for use by or in combination with an instruction execution system, device or equipment. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or equipment, or any suitable combination of the foregoing. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. A more specific example of a machine-readable storage medium may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0114] To provide interaction with a user, the systems and techniques described herein may be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and a pointing device (e.g., a mouse or trackball) through which the user can provide input to the electronic device. Other types of devices may also be used to provide interaction with the user; for example, the feedback provided to the user may be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user may be received in any form (including acoustic input, voice input, or tactile input).

[0115] The systems and techniques described herein may be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: a local area network (LAN), a wide area network (WAN), a blockchain network, and the Internet.

[0116] A computing system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The client and server relationship is generated by computer programs running on the corresponding computers and having a client-server relationship with each other. The server may be a cloud server, also known as a cloud computing server or cloud host, which is a host product in the cloud computing service system to solve the defects of difficult management and weak business scalability in traditional physical hosts and VPS services.

[0117] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0118] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for predicting reservoir damage in low-permeability and ultra-low-permeability oil reservoirs, characterized in that: include: Select the target reservoir core and determine the initial permeability of the core under simulated formation conditions; Continuously conducting a core permeability test on the target reservoir core and injecting an experimental liquid for soaking to obtain at least one set of core permeability data, wherein each set of core permeability data includes a time value and a core permeability at the time value; Based on the initial permeability of the core and the permeability data of the core, a core permeability variation curve is drawn, wherein the core permeability variation curve represents the variation of the core permeability over time; The core permeability variation curve is numerically simulated to predict the long-term damage of the reservoir.

2. The method according to claim 1, characterized in that The core permeability test includes: a core flow test, a static imbibition test and / or a core immersion test.

3. The method according to claim 1, characterized in that The liquid used for the injection experiment includes: gel breaking liquid, slippery water and fracturing fluid; Accordingly, the core permeability test is continuously performed on the target reservoir core and the experimental liquid is injected for immersion to obtain at least one set of core permeability data, including: The test pressure and temperature were maintained, and core permeability, porosity and throat changes were measured on the 1st, 3rd, 7th, 14th, 20th, 60th, 90th and 180th days to obtain core permeability data corresponding to the days.

4. The method according to claim 3, characterized in that: The step of drawing a core permeability variation curve based on the core initial permeability and the core permeability data comprises: Taking the initial permeability of the core as the core permeability data corresponding to the initial time; Draw an initial core permeability change curve based on the core permeability data corresponding to the initial time and the core permeability data corresponding to the number of days; The initially drawn core permeability change curve is fitted and corrected according to the porosity and / or throat changes to obtain the core permeability change curve, wherein the porosity and / or throat changes are determined by nuclear magnetic resonance or CT scanning.

5. The method according to claim 4, characterized in that The fitting correction of the initially drawn core permeability change curve according to the porosity and / or throat change to obtain the core permeability change curve includes: The initially drawn core permeability variation curve is fitted and corrected according to a first formula, wherein the first formula includes: Where K is the core permeability, φ is the porosity; T 2g is the geometric mean of the nuclear magnetic resonance T2 spectrum; C is the coefficient to be determined.

6. The method according to claim 4, characterized in that The fitting correction of the initially drawn core permeability change curve according to the porosity and / or throat change to obtain the core permeability change curve includes: The initially drawn core permeability variation curve is fitted and corrected according to a second formula, wherein the second formula includes: Where K is permeability; φ is porosity; R pt is the pore-throat ratio; r p is the pore radius, um; τ is the ratio of the actual pore length to the apparent length of the core.

7. The method according to claim 4, characterized in that The method of numerically simulating the core permeability change curve to predict the long-term damage of the reservoir includes: Importing the core permeability variation curve into a preset numerical simulation software; In the numerical simulation software, the core permeability change curve is fitted and corrected with the historical production output results to predict the long-term damage to the reservoir and the output after fracturing.

8. Low-permeability and ultra-low-permeability reservoir damage prediction device, characterized in that: include: The initial permeability determination unit is used to select the target reservoir core and determine the initial permeability of the core under simulated formation conditions; A core permeability data determination unit, used for continuously performing a core permeability test on the target reservoir core and injecting an experimental liquid for soaking to obtain at least one set of core permeability data, wherein each set of core permeability data includes a time value and a core permeability at the time value; A change curve drawing unit, used for drawing a core permeability change curve based on the core initial permeability and the core permeability data, wherein the core permeability change curve represents the change of the core permeability over time; The numerical simulation unit is used to perform numerical simulation on the core permeability variation curve to predict the long-term damage of the reservoir.

9. An electronic device, characterized in that: The electronic device comprises: At least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can execute the method for predicting reservoir damage in low-permeability and ultra-low-permeability oil reservoirs as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the method for predicting reservoir damage of a low-permeability or ultra-low-permeability oil reservoir according to any one of claims 1 to 7 when executed.

Images