A method and device for establishing a geomechanical model of a salt cavern gas storage group

Abstract

The present application provides a method and device for establishing a geomechanical model of a salt cavern gas storage group, which is used to provide scientific and effective data support for the evaluation of salt cavern gas storages to be established, such as ultra-deep salt cavern gas storage groups, and to ensure the reasonable selection of salt cavern gas storages to be established, such as ultra-deep salt cavern gas storage groups.

Description

Technical Field

[0001] The present application relates to the field of geology, and specifically to a method and device for establishing a geomechanical model of a salt cavern gas storage group. Background Art

[0002] With the rapid development of the economy and society, China's energy demand is increasing day by day. The huge energy demand, extremely high dependence on foreign oil and gas, and weak peak-shaving supply capacity make it urgent to establish a complete energy reserve system. Salt cavern underground gas storage has the advantages of safety, efficiency, stability, flexible injection and production mode, high injection and production rate, and large short-term throughput. Since the operation of the world's first salt cavern underground gas storage in the 1960s, as of 2020, there are more than 100 gas storages in operation in the world. Considering the limited storage capacity and working gas volume of single-chamber gas storage, in order to meet the needs of market peak-shaving and national energy reserves, it is usually necessary to build a gas storage group in the target area.

[0003] The location of salt cavern gas storage needs to consider many factors, including geological conditions, surface conditions, peak load demand, etc., and when a single chamber of a salt cavern gas storage is in operation, the impact of changes in injection and production pressure on the salt cavern itself needs to be considered. Since the gas pressure inside the cavity is less than the ground stress, the salt rock layer will creep under the action of the deviatoric stress, and the cavity volume will gradually shrink over time, and in severe cases, the roof will collapse. When constructing a salt cavern gas storage in an ultra-deep formation (usually referring to a cavern construction section with a burial depth of more than 2000m), the high ground temperature caused by the greater burial depth will increase the creep deformation rate of the salt rock, and the contraction of the salt cavern will increase significantly during the operation of the gas storage; in addition, when multiple salt cavern gas storages are in operation at the same time, the impact of changes in injection and production pressure of a single cavity on the adjacent cavity and even the entire cavity group needs to be considered, including the maximum displacement of the adjacent cavity, the distribution of the plastic zone, the volume shrinkage rate, and whether it affects the operating pressure range of the adjacent cavity. It can be seen that the evaluation of the ultra-deep salt cavern gas storage group to be established is of great significance.

[0004] In the process of studying the existing related technologies, the inventors found that the evaluation and processing of the ultra-deep salt cavern gas storage group to be established has the problem of poor accuracy, which affects the selection of the ultra-deep salt cavern gas storage group. Summary of the invention

[0005] The present application provides a method and device for establishing a geomechanical model of a salt cavern gas storage group, which is used to provide scientific and effective data support for the evaluation of salt cavern gas storages to be established, such as ultra-deep salt cavern gas storage groups, and to ensure the reasonable selection of salt cavern gas storages to be established, such as ultra-deep salt cavern gas storage groups.

[0006] In a first aspect, the present application provides a method for establishing a geomechanical model of a salt cavern gas storage group, the method comprising:

[0007] Obtain geological survey data for the target area where the salt cavern gas storage facility is to be built;

[0008] Determine the location of the data well based on the geological survey data, and initiate drilling processing of the corresponding data well based on the location of the data well;

[0009] Based on drilling processing, obtain the formation stress measurement data of the data well;

[0010] Based on the drilling process, determine the structural sedimentary characteristics and three-dimensional spatial distribution characteristics of the salt-bearing strata in the target area, and establish a three-dimensional seismic structural model corresponding to the salt-bearing strata in the target area;

[0011] Based on the formation stress measurement data and the 3D seismic structural model, the single cavity shape and geometric parameters of the salt cavern gas storage to be built are constructed;

[0012] Based on the drilling process, the physical and mechanical parameter data of the data well from the top plate to the bottom plate of the salt mine layer are obtained;

[0013] According to the physical and mechanical parameter data, the single cavity shape and geometric parameters of the salt cavern gas storage to be established, a single cavity three-dimensional geomechanical model of the salt cavern gas storage to be established is constructed, and according to the formation ground stress measurement data and the operating condition parameters, the corresponding boundary conditions and loads are applied to the single cavity three-dimensional geomechanical model;

[0014] Multiple single-cavity 3D geomechanical models are integrated to construct a group-cavity 3D geomechanical model.

[0015] In combination with the first aspect of the present application, in a first possible implementation of the first aspect of the present application, on the basis of drilling processing, obtaining formation in-situ stress measurement data of a data well includes:

[0016] The geostress value and geostress gradient in the salt layer are obtained by hydraulic fracturing. A complete section of the core is selected as the test section based on the wellbore measurement results, with a length of at least 6 times the borehole diameter. At different depths in the same wellbore, at least 3 layers are selected for testing, and each layer has more than 5 sections of effective fracturing in a single hole.

[0017] In combination with the first aspect of the present application, in a second possible implementation of the first aspect of the present application, based on the drilling process, determining the three-dimensional spatial distribution characteristics of the salt-bearing strata in the target area includes:

[0018] Through fine layer calibration algorithm, coherence body and curvature body fault interpretation algorithm, seismic attributes and seismic inversion algorithm, the three-dimensional spatial distribution characteristics of the salt-bearing strata in the target area are characterized.

[0019] In combination with the first aspect of the present application, in a third possible implementation of the first aspect of the present application, based on the drilling process, the physical and mechanical parameter data of the data well from the top plate to the bottom plate of the salt mine layer are obtained, including:

[0020] On the basis of drilling and processing, obtain conventional chemical analysis samples, salt mine identification samples and rock mechanics test samples from the top to the bottom of the salt mine layer in the data well;

[0021] Conventional chemical analysis samples are subjected to conventional chemical analysis tests, salt mine identification analysis tests are conducted on salt mine identification analysis tests, and rock mechanics analysis tests are conducted on rock mechanics test samples to obtain physical and mechanical parameter data, wherein conventional chemical analysis tests include salt rock layer water solubility analysis tests, interlayer solubility analysis tests, interlayer crushing and expansion analysis tests, density analysis tests, permeability analysis tests, porosity tests, and permeability analysis tests; salt mine identification analysis tests include water leaching analysis tests, acid leaching analysis tests, and infrared spectrum analysis tests; rock mechanics analysis tests include uniaxial compression analysis tests, triaxial compression analysis tests, Brazilian splitting analysis tests, and high-temperature creep analysis tests.

[0022] In combination with the first aspect of the present application, in a fourth possible implementation of the first aspect of the present application, after fusing multiple single cavity three-dimensional geomechanical models to construct a group cavity three-dimensional geomechanical model, the method includes:

[0023] Taking the storage capacity design, functional positioning and peak-shaving market demand of the gas storage group as simulation conditions, the injection and production cycle and operating conditions of the salt cavern gas storage to be established are calculated through the three-dimensional geomechanical model of the group cavity;

[0024] According to the injection-production cycle and operating conditions of the salt cavern gas storage to be established, the stability of the salt cavern gas storage to be established during operation is evaluated to obtain a stability evaluation result.

[0025] In a second aspect, the present application provides a device for establishing a geomechanical model of a salt cavern gas storage group, the device comprising:

[0026] An acquisition unit, used to acquire geological survey data of a target area where a salt cavern gas storage reservoir is to be built;

[0027] A determination unit, used to determine the location of the data well based on the geological survey data, and initiate drilling processing of the corresponding data well based on the location of the data well;

[0028] The acquisition unit is also used to acquire formation in-situ stress measurement data of the data well based on the drilling process;

[0029] The determination unit is also used to determine the structural sedimentary characteristics and three-dimensional spatial distribution characteristics of the salt-bearing strata in the target area based on the drilling process, and to establish a three-dimensional seismic structural model corresponding to the salt-bearing strata in the target area;

[0030] A construction unit, used to construct a single cavity shape and geometric parameters of a salt cavern gas storage reservoir to be built based on formation in-situ stress measurement data and a three-dimensional seismic structural model;

[0031] The acquisition unit is also used to acquire the physical and mechanical parameter data of the data well from the top plate to the bottom plate of the salt mine layer on the basis of drilling processing;

[0032] The construction unit is also used to construct a single-cavity three-dimensional geomechanical model of the salt cavern gas storage to be established according to the physical and mechanical parameter data, the single-cavity shape and geometric parameters of the salt cavern gas storage to be established, and to apply corresponding boundary conditions and loads to the single-cavity three-dimensional geomechanical model according to the formation ground stress measurement data and the operating condition parameters;

[0033] The fusion unit is used to fuse multiple single-cavity three-dimensional geomechanical models to construct a group-cavity three-dimensional geomechanical model.

[0034] In conjunction with the second aspect of the present application, in a first possible implementation manner of the second aspect of the present application, the acquiring unit is specifically configured to:

[0035] The geostress value and geostress gradient in the salt layer are obtained by hydraulic fracturing. A complete section of the core is selected as the test section based on the wellbore measurement results, with a length of at least 6 times the borehole diameter. At different depths in the same wellbore, at least 3 layers are selected for testing, and each layer has more than 5 sections of effective fracturing in a single hole.

[0036] In conjunction with the second aspect of the present application, in a second possible implementation manner of the second aspect of the present application, the determining unit is specifically configured to:

[0037] Through fine layer calibration algorithm, coherence body and curvature body fault interpretation algorithm, seismic attributes and seismic inversion algorithm, the three-dimensional spatial distribution characteristics of the salt-bearing strata in the target area are characterized.

[0038] In combination with the second aspect of the present application, in a third possible implementation manner of the second aspect of the present application, the acquiring unit is specifically configured to:

[0039] On the basis of drilling and processing, obtain conventional chemical analysis samples, salt mine identification samples and rock mechanics test samples from the top to the bottom of the salt mine layer in the data well;

[0040] Conventional chemical analysis samples are subjected to conventional chemical analysis tests, salt mine identification analysis tests are conducted on salt mine identification analysis tests, and rock mechanics analysis tests are conducted on rock mechanics test samples to obtain physical and mechanical parameter data, wherein conventional chemical analysis tests include salt rock layer water solubility analysis tests, interlayer solubility analysis tests, interlayer crushing and expansion analysis tests, density analysis tests, permeability analysis tests, porosity tests, and permeability analysis tests; salt mine identification analysis tests include water leaching analysis tests, acid leaching analysis tests, and infrared spectrum analysis tests; rock mechanics analysis tests include uniaxial compression analysis tests, triaxial compression analysis tests, Brazilian splitting analysis tests, and high-temperature creep analysis tests.

[0041] In combination with the second aspect of the present application, in a fourth possible implementation manner of the second aspect of the present application, the device further includes an evaluation unit, which is used to:

[0042] Taking the storage capacity design, functional positioning and peak-shaving market demand of the gas storage group as simulation conditions, the injection and production cycle and operating conditions of the salt cavern gas storage to be established are calculated through the three-dimensional geomechanical model of the group cavity;

[0043] According to the injection-production cycle and operating conditions of the salt cavern gas storage to be established, the stability of the salt cavern gas storage to be established during operation is evaluated to obtain a stability evaluation result.

[0044] In a third aspect, the present application provides a device for establishing a geomechanical model of a salt cavern gas storage group, comprising a processor and a memory, wherein a computer program is stored in the memory, and when the processor calls the computer program in the memory, the method provided in the first aspect of the present application or any possible implementation method of the first aspect of the present application is executed.

[0045] In a fourth aspect, the present application provides a computer-readable storage medium, which stores multiple instructions, and the instructions are suitable for a processor to load to execute the method provided by the first aspect of the present application or any possible implementation of the first aspect of the present application.

[0046] From the above content, it can be concluded that the present application has the following beneficial effects:

[0047] After the location of the data well is determined based on the geological data survey data and the drilling process of the corresponding data well is initiated, the formation stress measurement data, three-dimensional seismic structure model, single cavity shape and geometric parameters, and physical and mechanical parameter data corresponding to different angles of the salt cavern gas storage to be established are obtained, and based on the single cavity shape and geometric parameters and physical and mechanical parameter data, multiple single cavity three-dimensional geomechanical models of the salt cavern gas storage to be established are constructed, and then these single cavity three-dimensional geomechanical models are integrated to obtain a group cavity three-dimensional geomechanical model reflecting the salt cavern gas storage to be established as a whole. At this time, the group cavity three-dimensional geomechanical model can reflect the three-dimensional geomechanical characteristics of the salt cavern gas storage to be established from the overall level, provide scientific and effective data support for the evaluation of the salt cavern gas storage to be established, and ensure the reasonable selection of the salt cavern gas storage to be established, such as the ultra-deep salt cavern gas storage group. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0049] Figure 1 A schematic diagram of a flow chart of a method for establishing a geomechanical model of a salt cavern gas storage group in this application;

[0050] Figure 2 A schematic diagram of a result of a single cavity three-dimensional geomechanical model of this application;

[0051] Figure 3 A schematic diagram of a result of the three-dimensional geomechanical model of the group cavity of this application;

[0052] Figure 4 A structural schematic diagram of a device for establishing a geomechanical model of a salt cavern gas storage group in this application;

[0053] Figure 5 A structural schematic diagram of equipment for establishing a geomechanical model of a salt cavern gas storage group in this application. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of this application.

[0055] The terms "first", "second", etc. in the specification and claims of this application 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 interchangeable where appropriate, so that the embodiments described here can be implemented in an order other than that illustrated or described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or modules is not necessarily limited to those steps or modules clearly listed, but may include other steps or modules that are not clearly listed or inherent to these processes, methods, products or devices. The naming or numbering of steps in this application does not mean that the steps in the method flow must be executed in the time / logical sequence indicated by the naming or numbering. The process steps that have been named or numbered can change the execution order according to the technical purpose to be achieved, as long as the same or similar technical effects can be achieved.

[0056] The division of modules in this application is a logical division. There may be other division methods when it is implemented in actual applications. For example, multiple modules can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, and the indirect coupling or communication connection between modules can be electrical or other similar forms, which are not limited in this application. In addition, the modules or submodules described as separate components may or may not be physically separated, may or may not be physical modules, or may be distributed in multiple circuit modules, and some or all of the modules may be selected according to actual needs to achieve the purpose of the present application.

[0057] Before introducing the method for establishing the geomechanical model of the salt cavern gas storage group provided in the present application, the background content involved in the present application is first introduced.

[0058] The method, device and computer-readable storage medium for establishing a geomechanical model of a salt cavern gas storage group provided in the present application can be applied to a device for establishing a geomechanical model of a salt cavern gas storage group, and is used to provide scientific and effective data support for the evaluation of salt cavern gas storages to be established, such as in an ultra-deep salt cavern gas storage group, and to ensure the reasonable selection of salt cavern gas storages to be established, such as in an ultra-deep salt cavern gas storage group.

[0059] The method for establishing a geomechanical model of a salt cavern gas storage group mentioned in the present application may be executed by a device for establishing a geomechanical model of a salt cavern gas storage group, or a server, physical host, or user equipment (UE) that integrates the device for establishing a geomechanical model of a salt cavern gas storage group, or other different types of equipment for establishing a geomechanical model of a salt cavern gas storage group, or processing equipment. Among them, the device for establishing a geomechanical model of a salt cavern gas storage group may be implemented in hardware or software, and the UE may be a terminal device such as a smart phone, tablet computer, laptop computer, desktop computer, or personal digital assistant (PDA), and the device for establishing a geomechanical model of a salt cavern gas storage group may be set up in the form of a device cluster.

[0060] For example, the equipment for establishing the geomechanical model of a salt cavern gas storage group can be a workstation in a laboratory. In the laboratory, for a salt cavern gas storage to be established, such as an ultra-deep salt cavern gas storage group, a three-dimensional geomechanical model of the group cavity is established through this application. Furthermore, the evaluation results can be output based on the model to provide scientific and effective data support for related work on the salt cavern gas storage to be established.

[0061] Next, the method for establishing the geomechanical model of the salt cavern gas storage group provided in this application is introduced.

[0062] First, see Figure 1 , Figure 1 A schematic flow chart of the method for establishing a geomechanical model of a salt cavern gas storage group of the present application is shown. The method for establishing a geomechanical model of a salt cavern gas storage group provided by the present application may specifically include the following steps S101 to S108:

[0063] Step S101, obtaining geological survey data of the target area where the salt cavern gas storage is to be built;

[0064] It can be understood that the salt cavern gas storage to be established refers to a salt cavern gas storage that has not yet been established, which may be an artificially selected salt cavern gas storage, such as an ultra-deep salt cavern gas storage, or may be a salt cavern gas storage automatically selected by a machine.

[0065] When a salt cavern gas storage is to be built, it will have a certain range at the geological level, which can be referred to as a target area.

[0066] When evaluating the establishment of a salt cavern gas storage, a preliminary geological survey may be conducted in the early stage, and the present application may obtain the geological data obtained from the early geological survey.

[0067] For example, the geological survey data may include: detailed survey data, geophysical and geochemical prospecting data, drilling data, hydrogeological data, physical geography and historical earthquake data, salt mining history and mining technical conditions, etc. In the geological survey data, or based on the geological survey data, it is also possible to understand the geological structural background, sedimentary strata, fault distribution, salt mine distribution range, salt layer burial depth, salt layer thickness, fault conditions, aquifer and aquiclude distribution characteristics and other basic data of the target area.

[0068] It should be understood that step S101 can generally be understood as the retrieval of data, which can be retrieved from local or other devices storing data. Of course, in some special cases, it may also include triggering preliminary geological surveys and obtaining the processing of geological survey data.

[0069] Step S102, determining the location of the data well based on the geological survey data, and initiating drilling processing of the corresponding data well based on the location of the data well;

[0070] Based on the geological survey data, we can comprehensively consider the ownership of the mining area, the sedimentary characteristics of the rock salt ore body, the characteristics of the surrounding rock, the ground brine pipeline network, the nature of the land, the traffic conditions and other different site selection factors to determine the location of the data well and initiate the corresponding drilling process.

[0071] It is understood that the data well location may include not only the location of the data well base on the ground surface, but also its well depth, so that the drilling process can drill to the selected target layer.

[0072] Step S103, based on the drilling process, obtaining formation in-situ stress measurement data of the data well;

[0073] It can be understood that when the original geostress field is redistributed after the excavation of the salt mine, shrinkage deformation occurs due to the action of the original geostress field. Accurately obtaining geostress data can play an important role in simulating the stress-strain distribution around the salt cavity and in the evaluation of salt cavern gas storage.

[0074] In step S103, the acquisition of formation in-situ stress measurement data of the data well may be real-time detection processing or acquisition of detection results, which is adjusted according to actual conditions.

[0075] Specifically, based on the geological column chart, ground stress measurements can be carried out on target salt layer sections, interlayer sections, salt mine layer roof and floor, etc.

[0076] In the process of drilling, according to the specific adopted ground stress measurement scheme, corresponding measuring components can be configured at the probe to measure the ground stress measurement data of the data well.

[0077] Taking the ultra-deep salt cavern gas storage as an example, considering that the salt layer in the target area is buried at a large depth (greater than 1500m), the geostress value and its geostress gradient in the salt layer can be obtained by hydraulic fracturing. According to the wellbore measurement results, a complete section of the core is selected as the test section, with a length of at least 6 times the aperture. At different depths of the same wellbore, at least 3 layers are selected for testing, and each layer has more than 5 effective fractures in a single hole to ensure accurate and effective extraction of formation geostress measurement data.

[0078] Step S104, based on the drilling process, determining the structural sedimentary characteristics and three-dimensional spatial distribution characteristics of the salt-bearing strata in the target area, and establishing a three-dimensional seismic structural model corresponding to the salt-bearing strata in the target area;

[0079] In addition to measuring ground stress, during the drilling process, relevant three-dimensional structural features can also be collected to reflect the geological characteristics of the salt-bearing strata in the target area where the salt cavern gas storage is to be established from a structural perspective. The collection of the three-dimensional structural features is specifically carried out using three-dimensional seismic acquisition technology in this application. The three-dimensional structural model constructed based on the structural sedimentary features and three-dimensional spatial distribution features collected by the three-dimensional seismic acquisition technology is a three-dimensional seismic structural model.

[0080] Specifically, the three-dimensional spatial distribution characteristics of the salt-bearing strata in the target area can be precisely and accurately characterized through fine layer calibration algorithms, coherence body and curvature body fault interpretation algorithms, seismic attributes and seismic inversion algorithms.

[0081] In addition, based on the structural sedimentary characteristics and three-dimensional spatial distribution characteristics of the salt-bearing strata in the target area obtained according to the high-precision three-dimensional seismic results, in addition to constructing a three-dimensional seismic structural model, the corresponding lithofacies model and attribute model can also be constructed. Based on these models, blocks that are far away from the fault development zone and have stable salt layer distribution and large thickness can be selected as reservoir construction areas.

[0082] Step S105, constructing a single cavity shape and geometric parameters of the salt cavern gas storage to be built based on the formation in-situ stress measurement data and the three-dimensional seismic structure model;

[0083] Based on the formation ground stress measurement data and three-dimensional seismic structural model obtained from the two aspects of ground stress and three-dimensional structure, the specific cavity of the construction area of ​​the salt cavern gas storage to be built can be constructed.

[0084] Specifically, the single cavity shape and geometric parameters of the salt cavern gas storage to be established can be determined by comprehensively considering factors such as mechanical principles (corresponding to formation stress measurement data), the distribution of salt layers in the proposed gas storage area (corresponding to the three-dimensional seismic tectonic model), the operability of actual water-soluble cavity creation, and the height of the casing shoe.

[0085] The shape and geometric parameters of the single cavity mainly involve the top burial depth of the salt cavity, the top burial depth, the maximum diameter, the height of the salt cavity, etc., which lay the foundation for the three-dimensional geomechanical model of subsequent processing.

[0086] Step S106, based on the drilling process, obtaining physical and mechanical parameter data of the data well from the top plate to the bottom plate of the salt mine layer;

[0087] In addition, in order to construct a more complete three-dimensional geomechanical model of the salt cavern gas storage to be established, during the drilling process, in addition to determining the single cavity shape and its geometric parameters based on the structure, the physical and mechanical characteristics of different structures can be analyzed on the basis of the structure, thereby improving the physical and mechanical content of different structures or different locations of the salt cavern gas storage to be established.

[0088] The physical and mechanical parameter data corresponding to the physical and mechanical characteristics can also be obtained from the drilling process. In the acquisition process, it is mainly achieved by collecting samples for testing and analysis.

[0089] For example, based on drilling and processing, conventional chemical analysis samples, salt mine identification samples and rock mechanics test samples from the top to the bottom of the salt mine layer can be obtained from the data well;

[0090] Then, conventional chemical analysis samples can be subjected to conventional chemical analysis tests, salt mine identification samples can be subjected to salt mine identification analysis tests, and rock mechanics analysis tests can be conducted on rock mechanics test samples to obtain physical and mechanical parameter data;

[0091] Among them, conventional chemical analysis tests may specifically include salt rock layer water solubility analysis test, interlayer dissolution analysis test, interlayer crushing and expansion analysis test, density analysis test, permeability analysis test, porosity test and permeability analysis test;

[0092] Salt mine identification and analysis tests may specifically include water leaching analysis tests, acid leaching analysis tests, and infrared spectroscopy analysis tests;

[0093] Rock mechanics analysis tests may specifically include uniaxial compression analysis tests, triaxial compression analysis tests, Brazilian splitting analysis tests, and high temperature creep analysis tests.

[0094] Step S107, constructing a single-cavity three-dimensional geomechanical model of the salt cavern gas storage to be established according to the physical and mechanical parameter data, the single-cavity shape and geometric parameters of the salt cavern gas storage to be established, and applying corresponding boundary conditions and loads to the single-cavity three-dimensional geomechanical model according to the formation ground stress measurement data and the operating condition parameters;

[0095] At this time, after determining the physical and mechanical parameter data (corresponding to the physical and mechanical aspects), the single cavity shape and geometric parameters (corresponding to the structural aspects) of each single cavity of the salt cavern gas storage to be established, the two can be integrated to construct a single cavity three-dimensional geomechanical model of each single cavity of the salt cavern gas storage to be established. It can be understood that the single cavity three-dimensional geomechanical model represents the characteristics of the corresponding single cavity in terms of three-dimensional structure and physical mechanics.

[0096] In addition, considering the possible impact of the operating pressure and gas production rate on the stability of the salt cavern during the operation of the salt cavern gas storage, the corresponding formation stress measurement data and operating parameters of the single cavity can be combined to apply corresponding boundary conditions and loads to the single cavity three-dimensional geomechanical model;.

[0097] See also Figure 2 A schematic diagram of the results of the single-cavity three-dimensional geomechanical model of the present application is shown, which may include an overlying stratum 1, salt rock layers 2, 4, 6, interlayers 3, 5, an underlying stratum 7, and a single underground salt cavity 8 in the three-dimensional geomechanical content of the reaction. A simplified surface load of the deadweight of the overlying stratum is applied to the top of the single-cavity three-dimensional geomechanical model, and simply supported constraints are used on the lower surface and the four side surfaces to limit the corresponding normal displacement; the model perfectly characterizes the geological characteristics of the salt cavern gas storage corresponding to the stability analysis.

[0098] Step S108, fusing multiple single cavity three-dimensional geomechanical models to construct a group cavity three-dimensional geomechanical model.

[0099] It is easy to understand that the group cavity of the salt cavern gas storage reservoir is composed of multiple single cavities. It can be found from step S107 that it is processed for multiple single cavities contained in the salt cavern gas storage reservoir to be established, and the corresponding single cavity three-dimensional geomechanical models are constructed relatively independently with the single cavity as the unit. In step S108, the single cavity three-dimensional geomechanical models corresponding to these single cavities can be further integrated and fused to obtain a group cavity three-dimensional geomechanical model reflecting the overall salt cavern gas storage reservoir to be established.

[0100] refer to Figure 3 A schematic diagram of a result of the three-dimensional geomechanical model of the group cavity of the present application is shown, wherein 1-7 and Figure 2 Similarly, 8 and 9 represent different single cavities, and 10 represents a pillar. At this time, the three-dimensional geomechanical model of the group cavities obtained in this application can already reflect all aspects of the salt cavern gas storage to be established from an overall level, including the three-dimensional geological structure, physical and mechanical characteristics of each single cavity, and the interaction between multiple single cavities.

[0101] Therefore, the three-dimensional geomechanical model of the group cavity can be used to provide scientific and effective data support for the evaluation of the salt cavern gas storage to be established, to ensure the reasonable selection of the salt cavern gas storage to be established, such as the ultra-deep salt cavern gas storage group, and to provide data basis, data reference and data guidance for the selection of the salt cavern gas storage to be established for the staff or related equipment.

[0102] For example, in actual operation, the storage capacity design, functional positioning, and peak-shaving market demand of the gas storage group can be used as simulation conditions, and the injection and production cycle and operating conditions of the salt cavern gas storage to be established can be calculated through the three-dimensional geomechanical model of the group cavity. Then, based on the injection and production cycle and operating conditions of the salt cavern gas storage to be established, the stability of the salt cavern gas storage to be established during operation can be evaluated to obtain a stability evaluation result.

[0103] In the evaluation process, relevant indicators may also be involved. For example, considering that the salt rock cavity wall is under a complex stress state and has the characteristics of large deformation, self-repair of damage and strong plasticity, displacement, cavity creep volume shrinkage rate, shear expansion safety factor, equivalent plastic strain and plastic zone are used as evaluation indicators of the stability of a single cavity in a salt cavern gas storage. On this basis, the pillar safety factor can also be added as a stability evaluation indicator for a salt cavern gas storage group.

[0104] It can be seen from the above that the three-dimensional geomechanical model of the group cavity constructed in this application can reflect the three-dimensional geomechanical characteristics of the salt cavern gas storage to be established from an overall level, provide scientific and effective data support for the evaluation of the salt cavern gas storage to be established, and ensure the reasonable selection of the salt cavern gas storage to be established, such as the ultra-deep salt cavern gas storage group.

[0105] When evaluating the stability of the salt cavern gas storage to be established during operation in combination with the three-dimensional geomechanical model of the group cavity, it can effectively solve the difficult problems of the lack of an evaluation index system and the lack of standardized processes and steps for systematic stability evaluation in the geological conditions and stability evaluation of the salt cavern gas storage to be established in the ultra-deep salt cavern gas storage group. It has the advantages of an operating system, comprehensiveness, specificity, and clarity.

[0106] The above is an introduction to the method for establishing a geomechanical model of a salt cavern gas storage group provided in this application. In order to better implement the method for establishing a geomechanical model of a salt cavern gas storage group provided in this application, this application also provides a device for establishing a geomechanical model of a salt cavern gas storage group from the perspective of functional modules.

[0107] See also Figure 4 , Figure 4 This is a schematic diagram of a structure of a device for establishing a geomechanical model of a salt cavern gas storage group in the present application. In the present application, the device 400 for establishing a geomechanical model of a salt cavern gas storage group may specifically include the following structure:

[0108] An acquisition unit 401 is used to acquire geological survey data of a target area where a salt cavern gas storage reservoir is to be built;

[0109] The determination unit 402 is used to determine the location of the data well based on the geological survey data, and initiate drilling processing of the corresponding data well based on the location of the data well;

[0110] The acquisition unit 401 is also used to acquire the formation in-situ stress measurement data of the data well based on the drilling process;

[0111] The determination unit 402 is further used to determine the structural sedimentary characteristics and three-dimensional spatial distribution characteristics of the salt-bearing strata in the target area based on the drilling process, and to establish a three-dimensional seismic structural model corresponding to the salt-bearing strata in the target area;

[0112] A construction unit 403 is used to construct a single cavity shape and geometric parameters of a salt cavern gas storage to be built based on formation in-situ stress measurement data and a three-dimensional seismic structural model;

[0113] The acquisition unit 401 is also used to acquire physical and mechanical parameter data of the data well from the top plate to the bottom plate of the salt mine layer on the basis of the drilling process;

[0114] The construction unit 403 is further used to construct a single-cavity three-dimensional geomechanical model of the salt-cavern gas storage to be established according to the physical and mechanical parameter data, the single-cavity shape and geometric parameters of the salt-cavern gas storage to be established, and to apply corresponding boundary conditions and loads to the single-cavity three-dimensional geomechanical model according to the formation ground stress measurement data and the operating condition parameters;

[0115] The fusion unit 404 is used to fuse multiple single cavity three-dimensional geomechanical models to construct a group cavity three-dimensional geomechanical model.

[0116] In an exemplary implementation, the acquiring unit 401 is specifically configured to:

[0117] The geostress value and geostress gradient in the salt layer are obtained by hydraulic fracturing. A complete section of the core is selected as the test section based on the wellbore measurement results, with a length of at least 6 times the borehole diameter. At different depths in the same wellbore, at least 3 layers are selected for testing, and each layer has more than 5 sections of effective fracturing in a single hole.

[0118] In yet another exemplary implementation, the determining unit 402 is specifically configured to:

[0119] Through fine layer calibration algorithm, coherence body and curvature body fault interpretation algorithm, seismic attributes and seismic inversion algorithm, the three-dimensional spatial distribution characteristics of the salt-bearing strata in the target area are characterized.

[0120] In another exemplary implementation, the acquiring unit 401 is specifically configured to:

[0121] On the basis of drilling and processing, obtain conventional chemical analysis samples, salt mine identification samples and rock mechanics test samples from the top to the bottom of the salt mine layer in the data well;

[0122] Conventional chemical analysis samples are subjected to conventional chemical analysis tests, salt mine identification analysis tests are conducted on salt mine identification analysis tests, and rock mechanics analysis tests are conducted on rock mechanics test samples to obtain physical and mechanical parameter data, wherein conventional chemical analysis tests include salt rock layer water solubility analysis tests, interlayer solubility analysis tests, interlayer crushing and expansion analysis tests, density analysis tests, permeability analysis tests, porosity tests, and permeability analysis tests; salt mine identification analysis tests include water leaching analysis tests, acid leaching analysis tests, and infrared spectrum analysis tests; rock mechanics analysis tests include uniaxial compression analysis tests, triaxial compression analysis tests, Brazilian splitting analysis tests, and high-temperature creep analysis tests.

[0123] In yet another exemplary implementation, the apparatus further includes an evaluation unit 405, configured to:

[0124] Taking the storage capacity design, functional positioning and peak-shaving market demand of the gas storage group as simulation conditions, the injection and production cycle and operating conditions of the salt cavern gas storage to be established are calculated through the three-dimensional geomechanical model of the group cavity;

[0125] According to the injection-production cycle and operating conditions of the salt cavern gas storage to be established, the stability of the salt cavern gas storage to be established during operation is evaluated to obtain a stability evaluation result.

[0126] This application also provides a device for establishing a geomechanical model of a salt cavern gas storage reservoir group from the perspective of hardware structure, see Figure 5 , Figure 5 A schematic diagram of the structure of the device for establishing the geomechanical model of the salt cavern gas storage group of the present application is shown. Specifically, the device for establishing the geomechanical model of the salt cavern gas storage group of the present application may include a processor 501, a memory 502, and an input / output device 503. The processor 501 is used to execute the computer program stored in the memory 502 to implement the following Figure 1 The steps of the method for establishing a geomechanical model of a salt cavern gas storage group in the corresponding embodiment; or, the processor 501 is used to execute the computer program stored in the memory 502 to implement the following Figure 4 Corresponding to the functions of each unit in the embodiment, the memory 502 is used to store the processor 501 executing the above Figure 1 The computer program required for the method for establishing the geomechanical model of the salt cavern gas storage group in the corresponding embodiment.

[0127] Exemplarily, the computer program may be divided into one or more modules / units, one or more modules / units are stored in the memory 502, and executed by the processor 501 to complete the present application. One or more modules / units may be a series of computer program instruction segments capable of completing specific functions, and the instruction segments are used to describe the execution process of the computer program in the computer device.

[0128] The equipment for establishing the geomechanical model of the salt-cavern gas storage group may include, but is not limited to, a processor 501, a memory 502, and an input-output device 503. Those skilled in the art may understand that the diagram is merely an example of the equipment for establishing the geomechanical model of the salt-cavern gas storage group, and does not constitute a limitation on the equipment for establishing the geomechanical model of the salt-cavern gas storage group. The equipment may include more or fewer components than shown in the diagram, or a combination of certain components, or different components. For example, the equipment for establishing the geomechanical model of the salt-cavern gas storage group may also include a network access device, a bus, etc., and the processor 501, the memory 502, the input-output device 503, etc. are connected via the bus.

[0129] The processor 501 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor, etc. The processor is the control center of the equipment for establishing the geomechanical model of the salt cavern gas storage reservoir group, and uses various interfaces and lines to connect various parts of the entire equipment.

[0130] The memory 502 can be used to store computer programs and / or modules. The processor 501 implements various functions of the computer device by running or executing the computer programs and / or modules stored in the memory 502 and calling the data stored in the memory 502. The memory 502 can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, at least one application required for a function, etc.; the data storage area can store data created by using a device for establishing a geomechanical model of a salt cavern gas storage reservoir group, etc. In addition, the memory can include a high-speed random access memory, and can also include a non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card, a flash card (Flash Card), at least one disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0131] When the processor 501 is used to execute the computer program stored in the memory 502, the following functions can be implemented:

[0132] Obtain geological survey data for the target area where the salt cavern gas storage facility is to be built;

[0133] Determine the location of the data well based on the geological survey data, and initiate drilling processing of the corresponding data well based on the location of the data well;

[0134] Based on drilling processing, obtain the formation stress measurement data of the data well;

[0135] Based on the drilling process, determine the structural sedimentary characteristics and three-dimensional spatial distribution characteristics of the salt-bearing strata in the target area, and establish a three-dimensional seismic structural model corresponding to the salt-bearing strata in the target area;

[0136] Based on the formation stress measurement data and the 3D seismic structural model, the single cavity shape and geometric parameters of the salt cavern gas storage to be built are constructed;

[0137] Based on the drilling process, the physical and mechanical parameter data of the data well from the top plate to the bottom plate of the salt mine layer are obtained;

[0138] According to the physical and mechanical parameter data, the single cavity shape and geometric parameters of the salt cavern gas storage to be established, a single cavity three-dimensional geomechanical model of the salt cavern gas storage to be established is constructed, and according to the formation ground stress measurement data and the operating condition parameters, the corresponding boundary conditions and loads are applied to the single cavity three-dimensional geomechanical model;

[0139] Multiple single-cavity 3D geomechanical models are integrated to construct a group-cavity 3D geomechanical model.

[0140] Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working process of the above-described salt cavern gas storage group geomechanical model establishment device, equipment and corresponding units can refer to the following. Figure 1 The description of the method for establishing the geomechanical model of the salt cavern gas storage group in the corresponding embodiment will not be repeated here.

[0141] A person of ordinary skill in the art will appreciate that all or part of the steps in the various methods of the above embodiments may be completed by instructions, or by controlling related hardware through instructions. The instructions may be stored in a computer-readable storage medium and loaded and executed by a processor.

[0142] To this end, the present application provides a computer-readable storage medium, in which a plurality of instructions are stored, and the instructions can be loaded by a processor to execute the present application as follows: Figure 1 The steps of the method for establishing the geomechanical model of the salt cavern gas storage group in the corresponding embodiment, the specific operation can be referred to as follows Figure 1 The description of the method for establishing the geomechanical model of the salt cavern gas storage group in the corresponding embodiment will not be repeated here.

[0143] The computer-readable storage medium may include: a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, etc.

[0144] Due to the instructions stored in the computer-readable storage medium, the present application can be executed. Figure 1 The steps of the method for establishing the geomechanical model of the salt cavern gas storage group in the corresponding embodiment, therefore, the present application can be realized as follows Figure 1 The beneficial effects that can be achieved by the method for establishing a geomechanical model of a salt cavern gas storage group in the corresponding embodiment are detailed in the previous description and will not be repeated here.

[0145] The above is a detailed introduction to the method, device, equipment and computer-readable storage medium for establishing a geomechanical model of a salt cavern gas storage group provided by the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. At the same time, for technicians in this field, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A method for establishing a geomechanical model of a salt cavern gas storage group. It is characterized in that The method comprises: Obtain geological survey data for the target area where the salt cavern gas storage facility is to be built; Determine the location of the data well based on the geological survey data, and initiate drilling processing of the corresponding data well based on the location of the data well; Based on the drilling process, obtaining formation in-situ stress measurement data of the data well; Based on the drilling process, determining the structural sedimentary characteristics and three-dimensional spatial distribution characteristics of the salt-bearing strata in the target area, and establishing a three-dimensional seismic structural model corresponding to the salt-bearing strata in the target area; Based on the formation in-situ stress measurement data and the three-dimensional seismic structural model, constructing the single cavity shape and geometric parameters of the salt cavern gas storage to be established; Based on the drilling process, obtaining the physical and mechanical parameter data of the data well from the top plate to the bottom plate of the salt mine layer; A single-cavity three-dimensional geomechanical model of the salt cavern gas storage to be established is constructed according to the physical and mechanical parameter data, the single-cavity shape and geometric parameters of the salt cavern gas storage to be established, and corresponding boundary conditions and loads are applied to the single-cavity three-dimensional geomechanical model according to the formation ground stress measurement data and the operating condition parameters; A plurality of the single cavity three-dimensional geomechanical models are integrated to construct a group cavity three-dimensional geomechanical model.

2. The method according to claim 1, It is characterized in that The step of obtaining formation in-situ stress measurement data of the data well based on the drilling process includes: The geostress value and geostress gradient in the salt layer are obtained by hydraulic fracturing. A complete section of the core is selected as the test section based on the wellbore measurement results, with a length of at least 6 times the borehole diameter. At different depths in the same wellbore, at least 3 layers are selected for testing, and each layer has more than 5 sections of effective fracturing in a single hole.

3. The method according to claim 1, It is characterized in that Based on the drilling process, the three-dimensional spatial distribution characteristics of the salt-bearing strata in the target area are determined, including: The three-dimensional spatial distribution characteristics of the salt-bearing strata in the target area are characterized by means of fine layer calibration algorithms, coherence body and curvature body fault interpretation algorithms, seismic attributes and seismic inversion algorithms.

4. The method according to claim 1, It is characterized in that Based on the drilling process, the physical and mechanical parameter data of the data well from the top plate to the bottom plate of the salt mine layer are obtained, including: On the basis of the drilling process, conventional chemical analysis samples, salt mine identification samples and rock mechanics test samples are obtained from the top plate to the bottom plate of the salt mine layer in the data well; The conventional chemical analysis samples are subjected to conventional chemical analysis tests, the salt mine identification analysis tests are subjected to salt mine identification analysis tests, and the rock mechanics analysis tests are subjected to rock mechanics analysis tests to obtain the physical and mechanical parameter data, wherein the conventional chemical analysis tests include salt rock layer water solubility analysis tests, interlayer dissolution analysis tests, interlayer crushing and expansion analysis tests, density analysis tests, permeability analysis tests, porosity tests, and permeability analysis tests; the salt mine identification analysis tests include water leaching analysis tests, acid leaching analysis tests, and infrared spectrum analysis tests; and the rock mechanics analysis tests include uniaxial compression analysis tests, triaxial compression analysis tests, Brazilian splitting analysis tests, and high-temperature creep analysis tests.

5. The method according to claim 1, It is characterized in that After fusing a plurality of the single cavity three-dimensional geomechanical models to construct a group cavity three-dimensional geomechanical model, the method includes: Taking the storage capacity design, functional positioning and peak-shaving market demand of the gas storage group as simulation conditions, the injection and production cycle and operating conditions of the salt cavern gas storage to be established are calculated through the three-dimensional geomechanical model of the group cavity; According to the injection-production cycle and operating conditions of the salt cavern gas storage to be established, the stability of the salt cavern gas storage to be established during operation is evaluated to obtain a stability evaluation result.

6. A device for establishing a geomechanical model of a salt cavern gas storage group, It is characterized in that The device comprises: An acquisition unit, used to acquire geological survey data of a target area where a salt cavern gas storage reservoir is to be built; A determination unit, configured to determine a data well location based on the geological survey data, and initiate drilling processing of the corresponding data well based on the data well location; The acquisition unit is further used to acquire formation in-situ stress measurement data of the data well based on the drilling process; The determination unit is further used to determine the structural sedimentary characteristics and three-dimensional spatial distribution characteristics of the salt-bearing strata in the target area based on the drilling process, and establish a three-dimensional seismic structural model corresponding to the salt-bearing strata in the target area; A construction unit, used to construct the single cavity shape and geometric parameters of the salt cavern gas storage to be established based on the formation in-situ stress measurement data and the three-dimensional seismic structure model; The acquisition unit is further used to acquire the physical and mechanical parameter data of the data well from the top plate to the bottom plate of the salt mine layer based on the drilling process; The construction unit is further used to construct a single-cavity three-dimensional geomechanical model of the salt cavern gas storage to be established according to the physical and mechanical parameter data, the single-cavity shape and geometric parameters of the salt cavern gas storage to be established, and to apply corresponding boundary conditions and loads to the single-cavity three-dimensional geomechanical model according to the formation ground stress measurement data and the operating condition parameters; The fusion unit is used to fuse a plurality of the single cavity three-dimensional geomechanical models to construct a group cavity three-dimensional geomechanical model.

7. The device according to claim 6, It is characterized in that The acquisition unit is specifically used for: The geostress value and geostress gradient in the salt layer are obtained by hydraulic fracturing. A complete section of the core is selected as the test section based on the wellbore measurement results, with a length of at least 6 times the borehole diameter. At different depths in the same wellbore, at least 3 layers are selected for testing, and each layer has more than 5 sections of effective fracturing in a single hole.

8. The device according to claim 6, It is characterized in that The determining unit is specifically configured to: The three-dimensional spatial distribution characteristics of the salt-bearing strata in the target area are characterized by means of fine layer calibration algorithms, coherence body and curvature body fault interpretation algorithms, seismic attributes and seismic inversion algorithms.

9. The device according to claim 6, It is characterized in that The acquisition unit is specifically used for: On the basis of the drilling process, conventional chemical analysis samples, salt mine identification samples and rock mechanics test samples are obtained from the top plate to the bottom plate of the salt mine layer in the data well; The conventional chemical analysis samples are subjected to conventional chemical analysis tests, the salt mine identification analysis tests are subjected to salt mine identification analysis tests, and the rock mechanics analysis tests are subjected to rock mechanics analysis tests to obtain the physical and mechanical parameter data, wherein the conventional chemical analysis tests include salt rock layer water solubility analysis tests, interlayer dissolution analysis tests, interlayer crushing and expansion analysis tests, density analysis tests, permeability analysis tests, porosity tests, and permeability analysis tests; the salt mine identification analysis tests include water leaching analysis tests, acid leaching analysis tests, and infrared spectrum analysis tests; and the rock mechanics analysis tests include uniaxial compression analysis tests, triaxial compression analysis tests, Brazilian splitting analysis tests, and high-temperature creep analysis tests.

10. The device according to claim 6, It is characterized in that The device further comprises an evaluation unit for: Taking the storage capacity design, functional positioning and peak-shaving market demand of the gas storage group as simulation conditions, the injection and production cycle and operating conditions of the salt cavern gas storage to be established are calculated through the three-dimensional geomechanical model of the group cavity; According to the injection-production cycle and operating conditions of the salt cavern gas storage to be established, the stability of the salt cavern gas storage to be established during operation is evaluated to obtain a stability evaluation result.

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