Oil reservoir injection and production scheme design method, system, storage medium and electronic equipment

Abstract

The present invention provides a method, device, storage medium and electronic device for designing an injection and production scheme for an oil reservoir, and relates to the technical field of oil and gas exploration and development. The method comprises: establishing a three-dimensional geological model of the oil reservoir based on the geological information of the oil reservoir to be designed; the three-dimensional geological model includes the distribution information of the wells that have been drilled in the oil reservoir; performing numerical simulation of the oil reservoir on the three-dimensional geological model to obtain the distribution information of the remaining oil in the oil reservoir; determining the injection and production well group based on the remaining oil distribution information, the distribution information of the wells that have been drilled and the basic characteristics of the wells that have been drilled that have been acquired in advance; and determining the injection and production parameters of the injection and production well group to obtain the injection and production scheme of the oil reservoir. The technical scheme provided by the present invention can accurately and effectively determine the injection and production scheme of the oil reservoir to be designed, thereby greatly improving the efficiency of the injection and production work of the oil reservoir.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas exploration and development, and in particular to a method, system, storage medium and electronic equipment for designing an oil reservoir injection and production scheme. Background Art

[0002] The fracture-cave reservoirs in Tahe Oilfield have effectively supplemented the formation energy through water injection and unit water injection, which has improved the development effect to a certain extent. However, as the water injection effect deteriorated, in order to mobilize the remaining oil in the upper part of the fracture-cave body near the well, the oilfield implemented a single-well nitrogen injection test in 2012. In the northern part of the S48 fracture-cave unit in the 4th area of ​​Tahe Oilfield, which was developed earlier, the TK440 well was selected to carry out the liquid nitrogen injection test. The test adopted a slug injection method, with a total of 700 cubic meters of liquid nitrogen injected. After the well was blocked for 10 days, the well was opened and reversed for production. By the end of September of the same year, the cumulative oil production increased by 2,600 tons, and the single-well on-site nitrogen injection oil production increased significantly.

[0003] In order to tap the remaining oil in the high part of the inter-well fracture cave, Kang Zhijiang first proposed the mechanism of efficient oil recovery by cave roof gas drive in November 2009. In 2014, the Tahe Oilfield officially implemented nitrogen drive test. As of June 2017, a total of 43 nitrogen drive well groups were implemented, covering 32 units, and the gas injection covered geological reserves of 85.49 million tons. A total of 194 million cubic meters of nitrogen were injected, with a total of 301,500 cubic meters of associated water, a total increase of 327,400 tons of oil, and a total gas-to-oil ratio of 0.53 tons / cubic meter. The nitrogen drive of the well group has achieved good development results as a whole, and has developed into an important technology for improving the recovery of oil reservoirs after water drive.

[0004] However, the gas injection effect gradually deteriorated in the middle and late stages of reservoir gas injection development, and the remaining oil after a large amount of water flooding could not be used. In order to improve the gas injection development effect of such reservoirs, it is necessary to carry out targeted research on the mechanism of multi-well unit gas injection to improve oil recovery. However, there is currently no systematic and complete method for designing reservoir injection and production plans. Summary of the invention

[0005] In response to the above-mentioned problems in the prior art, the present application proposes a method, system, storage medium and electronic equipment for designing an oil reservoir injection and production plan, which can accurately and effectively determine the injection and production plan of the oil reservoir to be designed, thereby greatly improving the efficiency of oil reservoir injection and production work.

[0006] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0007] In a first aspect, an embodiment of the present invention provides a method for designing an injection and production plan for an oil reservoir, the method comprising:

[0008] Based on the acquired geological information of the oil reservoir to be designed, a three-dimensional geological model of the oil reservoir is established; the three-dimensional geological model includes distribution information of the wells drilled in the oil reservoir;

[0009] Performing reservoir numerical simulation on the three-dimensional geological model to obtain the remaining oil distribution information in the reservoir;

[0010] Determine an injection-production well group based on the remaining oil distribution information, the distribution information of the drilled wells and pre-acquired basic characteristics of the drilled wells;

[0011] The injection and production parameters of the injection and production well group are determined to obtain an injection and production plan for the oil reservoir.

[0012] Furthermore, before determining the injection-production well group based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells, the method further includes:

[0013] The type of injection and production plan is determined based on the type of reservoir, the current development stage and historical development information.

[0014] Preferably, when the injection-production scheme type is a single-well nitrogen injection and huff-and-puff scheme, determining the injection-production well group based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells includes:

[0015] Based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells, a plurality of wells to be selected are determined; wherein the wells to be selected are gas-injected wells;

[0016] Determining well selection parameters corresponding to each of the wells to be selected based on geological information, construction information and gas injection information of the wells to be selected;

[0017] Using each group of the well selection parameters as the input of a pre-trained gas injection oil increase prediction model to predict the oil increase effect corresponding to each of the wells to be selected;

[0018] Based on the oil-increasing effect, a target well is selected from the plurality of candidate wells as the injection-production well group.

[0019] Preferably, when the injection-production scheme type is a single-well nitrogen drive scheme or a multi-well nitrogen drive scheme, determining the injection-production well group based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells includes:

[0020] Based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells, a plurality of groups of wells to be selected are determined; wherein the wells to be selected are water-injected wells;

[0021] Determining a target well group based on connectivity between wells in each group of the candidate wells;

[0022] Based on the tracer monitoring data acquired in advance, the gas injection wells and the oil production wells in the target well group are determined to determine the injection and production well group.

[0023] Preferably, when the injection-production scheme type is a single-well nitrogen injection huff-and-puff scheme, determining the injection-production parameters of the injection-production well group to obtain the injection-production scheme of the oil reservoir includes:

[0024] The injection and production parameters of the injection and production well group are determined based on a pre-established chart to obtain an injection and production plan for the oil reservoir; wherein the chart reflects the corresponding relationship between the fracture and cave genesis type of the oil reservoir and the injection and production parameters.

[0025] Preferably, when the injection-production scheme type is a single-well nitrogen drive scheme, a multi-well nitrogen drive scheme, or a unit nitrogen injection scheme, determining the injection-production parameters of the injection-production well group to obtain the injection-production scheme of the oil reservoir includes:

[0026] Based on the pre-established geological model of the injection-production well group and multiple groups of preset injection-production parameters, simulate and calculate the oil-increasing effect under each group of the preset injection-production parameters;

[0027] Based on the oil-increasing effect, target injection-production parameters are selected from the multiple groups of preset injection-production parameters as the injection-production parameters of the injection-production well group.

[0028] Preferably, the geological information of the oil reservoir to be designed includes: historical seismic data, fracture-cavity reservoir type, well logging data, core test data and drilling test data of the oil reservoir to be designed; the three-dimensional geological model of the oil reservoir is established based on the acquired geological information of the oil reservoir to be designed, including:

[0029] Based on the historical seismic data, fracture-cavity reservoir types, well logging data, core test data and drilling test data, the karst cave information, dissolution hole information, fault information and fracture spatial distribution information of the oil reservoir are obtained;

[0030] Based on the karst cave information, karst pore information, fault information and fracture spatial distribution information of the oil reservoir, a karst cave model, a karst pore model and a fault model are established respectively;

[0031] The cave model, the dissolution pore model and the fracture model are integrated to obtain a three-dimensional geological model of the oil reservoir.

[0032] Furthermore, the method further comprises:

[0033] Based on the dynamic data of a single well drilled in the oil reservoir, the three-dimensional geological model is corrected to obtain a corrected three-dimensional geological model;

[0034] The performing of reservoir numerical simulation on the three-dimensional geological model to obtain the remaining oil distribution information in the reservoir includes:

[0035] The corrected three-dimensional geological model is subjected to reservoir numerical simulation to obtain the remaining oil distribution information in the reservoir.

[0036] Furthermore, the method further comprises:

[0037] Based on a pre-established economic evaluation model, the economic benefits of the injection and production scheme of the oil reservoir are evaluated.

[0038] In a second aspect, an embodiment of the present invention provides a system for designing an oil reservoir injection and production plan, the system comprising:

[0039] A three-dimensional modeling module, used to establish a three-dimensional geological model of the reservoir based on the acquired geological information of the reservoir to be designed; the three-dimensional geological model includes the distribution information of the wells drilled in the reservoir;

[0040] A numerical simulation module, used to perform numerical simulation of the oil reservoir on the three-dimensional geological model to obtain the remaining oil distribution information in the oil reservoir;

[0041] An injection-production well group determination module is used to determine the injection-production well group based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells;

[0042] The injection-production parameter determination module is used to determine the injection-production parameters of the injection-production well group to obtain the injection-production plan of the oil reservoir.

[0043] In a third aspect, an embodiment of the present invention provides a storage medium having program code stored thereon, and when the program code is executed by a processor, a method for designing an injection and production plan for a reservoir as described in any one of the above embodiments is implemented.

[0044] In a fourth aspect, an embodiment of the present invention provides an electronic device, comprising a memory and a processor, wherein the memory stores program code that can be executed on the processor, and when the program code is executed by the processor, a method for designing an oil reservoir injection and production plan as described in any one of the above embodiments is implemented.

[0045] The method, system, storage medium and electronic device for designing an injection and production scheme for an oil reservoir provided by the embodiment of the present invention can obtain the distribution information of the remaining oil in the oil reservoir by performing numerical simulation of the three-dimensional geological model of the oil reservoir to be designed; based on the remaining oil distribution information, the distribution information of the wells already drilled in the oil reservoir and the basic characteristics of the wells already drilled, the injection and production well group can be determined; after the injection and production parameters of the injection and production well group are determined, the injection and production scheme of the oil reservoir can be obtained. Compared with the prior art, the present invention provides a set of systematic and complete oil reservoir injection and production scheme designs, which can be automatically executed on electronic equipment / electronic terminals, so that the injection and production scheme of the oil reservoir to be designed can be accurately and effectively determined, thereby greatly improving the efficiency of oil reservoir injection and production work. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The scope of the present invention can be better understood by reading the detailed description of the following exemplary embodiments in conjunction with the accompanying drawings. The accompanying drawings included are:

[0047] Figure 1 The method flow of the embodiment of the present invention is Figure 1 ;

[0048] Figure 2 The method flow of the embodiment of the present invention is Figure 2 ;

[0049] Figure 3 Schematic diagram of two groups of fracture models established for embodiments of the present invention;

[0050] Figure 4 A schematic diagram of a three-dimensional geological model of an oil reservoir to be designed established in an embodiment of the present invention;

[0051] Figure 5A and Figure 5B is a prediction curve of oil production and water content of an oil production well in an embodiment of the present invention;

[0052] Figure 6 The system structure of the embodiment of the present invention is Figure 1 ;

[0053] Figure 7 The system structure of the embodiment of the present invention is Figure 2 . DETAILED DESCRIPTION

[0054] In order to make the purpose, technical solutions and advantages of the present invention clearer, the implementation method of the present invention will be described in detail below in conjunction with the accompanying drawings and embodiments, so that the implementation process of how the present invention applies technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0055] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0056] Embodiment 1

[0057] According to an embodiment of the present invention, a method for designing an injection and production plan for an oil reservoir is provided. Figure 1 As shown, the method described in this embodiment includes:

[0058] Step S101, based on the acquired geological information of the oil reservoir to be designed, a three-dimensional geological model of the oil reservoir is established; the three-dimensional geological model includes the distribution information of the wells drilled in the oil reservoir;

[0059] In this embodiment, the geological information of the oil reservoir to be designed includes: historical seismic data, fracture-cavity reservoir type, well logging data, core test data and drilling test data of the oil reservoir to be designed; the three-dimensional geological model of the oil reservoir is established based on the acquired geological information of the oil reservoir to be designed, including:

[0060] Based on the historical seismic data, fracture-vuggy reservoir types, logging data, core test data and drilling test data, the karst cave information, dissolution pore-vuggy information, fracture information and fracture spatial distribution information of the oil reservoir are obtained; based on the karst cave information, dissolution pore-vuggy information, fracture information and fracture spatial distribution information of the oil reservoir, a karst cave model, a dissolution pore-vuggy model and a fracture model are established respectively; the karst cave model, the dissolution pore-vuggy model and the fracture model are merged to obtain a three-dimensional geological model of the oil reservoir.

[0061] Specifically, the above-mentioned historical seismic data can be obtained through the seismic data of the oil reservoir, and the logging data can be obtained through various logging methods such as imaging logging. The historical seismic data, fracture-cavity reservoir type, logging data, core test data and drilling test data are used to comprehensively describe the spatial distribution and physical properties of caves, dissolved pores, faults and fractures. A hierarchical classification modeling method is adopted to establish cave models, dissolved pore models and fault models of different scales respectively, and the above-mentioned different types of models are integrated into a three-dimensional geological model of the oil reservoir to be designed. In this embodiment, the three-dimensional geological model is a three-dimensional geological model of a fracture-cavity carbonate reservoir. Relying on this three-dimensional geological model, key parameters such as the fracture-cavity type, connectivity, physical properties and heterogeneity of the fracture-cavity body in the oil reservoir can be determined.

[0062] In this embodiment, after establishing the above three-dimensional geological model, the method further includes: based on the single well dynamic data of the wells drilled in the reservoir, correcting the three-dimensional geological model to obtain a corrected three-dimensional geological model to comprehensively describe the spatial distribution characteristics of the fracture-cavity body in the reservoir. Then, step S102 in this embodiment includes: performing reservoir numerical simulation on the corrected three-dimensional geological model to obtain the remaining oil distribution information in the reservoir.

[0063] Step S102, performing reservoir numerical simulation on the three-dimensional geological model to obtain the remaining oil distribution information in the reservoir;

[0064] In this embodiment, the three-dimensional geological model of the oil reservoir is numerically simulated according to the composite medium model. Specifically, the numerical simulation is performed according to the type, scale and flow state classification of each reservoir body in the oil reservoir to reflect the fluid flow characteristics in large fractures and large caves in the oil reservoir, quantitatively characterize the type, occurrence mode, spatial distribution characteristics and different types of remaining reserves of the remaining oil after water flooding, comprehensively evaluate the remaining oil in the oil reservoir after water flooding, and obtain the remaining oil distribution information in the oil reservoir.

[0065] Furthermore, this embodiment can also rely on the above-mentioned three-dimensional geological model, mainly through the numerical simulation method of fracture-cavity oil reservoirs, to quantitatively calculate key parameters such as "well-controlled remaining reserves", "cavern top remaining reserves", "residual hill remaining reserves" and "remaining reserves within 60m below the top surface of the structure", and quantitatively evaluate the nitrogen injection potential of the target block.

[0066] Step S103, determining an injection-production well group based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells;

[0067] In this embodiment, before determining the injection-production well group based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells, the method further includes: determining the type of injection-production scheme based on the type of the oil reservoir, the current development stage and the historical development information to determine the research target. The historical development information includes the main problems currently faced by the oil reservoir, and the type of injection-production scheme is comprehensively determined according to the above method.

[0068] There are four specific types of injection and production schemes described in this embodiment, namely: single-well nitrogen injection and huff-and-puff scheme, single-well nitrogen flooding scheme, multi-well nitrogen flooding scheme and unit nitrogen injection scheme. Of course, in actual applications, other types of injection and production schemes can also be proposed according to actual conditions, and this embodiment does not limit this.

[0069] In this embodiment, when the injection-production scheme type is a single-well nitrogen injection and huff-and-puff scheme, determining the injection-production well group based on the remaining oil distribution information, the distribution information of the drilled wells, and the pre-acquired basic characteristics of the drilled wells includes:

[0070] Based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells, multiple wells to be selected are determined; wherein the wells to be selected are gas-injected wells; based on the geological information, construction information and gas injection information of the wells to be selected, well selection parameters corresponding to each of the wells to be selected are determined; each group of the well selection parameters is used as the input of a pre-trained gas injection and oil increase prediction model to predict the oil increase effect corresponding to each of the wells to be selected; based on the oil increase effect, a target well is selected from the multiple wells to be selected as the injection-production well group.

[0071] Specifically, for the single-well nitrogen injection huff-and-puff scheme, the following method is used to select the well:

[0072] Firstly, based on the distribution information of remaining oil and the distribution information of drilled wells, wells with failed water injection, high water content (water content greater than 85%) or low production (daily production less than 5t / d) in the reservoir study area are selected as candidate wells.

[0073] Then, based on the geological information of the wells to be selected, the historical construction information and historical gas injection information of the wells to be selected collected on site, the well selection parameters corresponding to each well to be selected are determined. In order to fully reflect the characteristics of the wells to be selected, the well selection parameters of each well to be selected must be greater than 5, and must include geological, construction and gas injection effect parameters.

[0074] In this embodiment, there are 17 well selection parameters for each well to be selected. For each well selection parameter, when it has different attributes / types, it is distinguished by assigning different values ​​to it:

[0075] · Type of fracture-cave genesis: surface karst (value 1), underground river karst (value 0.5), and fault-controlled karst (value 0.1);

[0076] Reservoir type: cave type (assigned value 1), fracture-pore type (assigned value 0.5), fracture type (assigned value 0.1);

[0077] · Reserve size: actual value calculated using reservoir engineering methods;

[0078] · Remaining oil reserves in the gas injection layer: the actual value calculated by reservoir engineering methods;

[0079] Well-reservoir relationship: the well is located in the upper part of the reservoir (assigned value 1 / 4), in the middle part of the reservoir (assigned value 1 / 2), and in the lower part of the reservoir (assigned value 3 / 4);

[0080] Bottom water energy: actual value calculated by reservoir engineering methods;

[0081] ·Fault configuration relationship: passing through the source fault (assigned value 0.5), not passing through the source fault (assigned value 1);

[0082] · Reservoir inclination angle: derived from geological analysis;

[0083] ·Equivalent porosity: calculated based on well logging data;

[0084] Recovery degree: the actual value calculated by reservoir engineering methods;

[0085] Total gas injection volume: actual gas injection construction data;

[0086] Gas injection speed: actual gas injection construction data;

[0087] · Timing of water injection: when to start gas injection at a certain water content, based on the actual data of the production wells;

[0088] Total water injection volume: actual gas injection construction data;

[0089] Water injection speed: actual gas injection construction data;

[0090] Well soaking time: actual gas injection construction data;

[0091] Recoverable reserves after gas injection: actual value calculated using reservoir engineering methods.

[0092] After determining the above-mentioned well selection parameters for each well to be selected, each set of well selection parameters is used as the input of the pre-trained gas injection oil increase prediction model, and the gas injection oil increase prediction model is used to predict the oil increase effect corresponding to each well to be selected. Among them, the gas injection oil increase prediction model is a prediction model constructed by learning the well selection parameters and oil increase amount of the gas injected wells through neural network training, and the model is used to predict the oil increase effect of nitrogen injection.

[0093] Afterwards, based on the amount of oil production increased by nitrogen injection in each candidate well, combined with the remaining oil reserves of each well, well-reservoir relationship, well conditions and other information, the preferred gas injection wells are ranked and the target injection-production well group is selected from the preferred gas injection wells.

[0094] In this embodiment, when the injection-production scheme type is a single-well nitrogen drive scheme or a multi-well nitrogen drive scheme, determining the injection-production well group based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells includes:

[0095] Based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells, multiple groups of candidate wells are determined; wherein the candidate wells are water-injected wells; based on the connectivity between the wells in each group of the candidate wells, a target well group is determined; based on the pre-acquired tracer monitoring data, the gas injection wells and oil production wells in the target well group are determined to determine the injection-production well group.

[0096] Specifically, for a single-well nitrogen flooding scheme or a multi-well nitrogen flooding scheme, the following methods are used to select wells:

[0097] First, based on the remaining oil distribution information and the distribution information of the drilled wells, low-yield (daily production less than 3t / d) and high water content (water content greater than 97%) wells are selected as gas injection wells, and the selected gas injection wells are water-injected wells. At the same time, the wells with good connectivity between the wells in each group of candidate wells are determined as the target well group.

[0098] Then, combined with the results of the remaining oil distribution, the focus is on whether there are high points or cave tops and the size of the remaining oil in the attic around the well, and there are no large faults, and the gas injection well group is ranked first. At the same time, based on the tracer monitoring data, the gas injection wells and oil production wells in the target well group are determined.

[0099] In this embodiment, when the injection-production scheme type is a unit nitrogen injection scheme, the following method is used to select wells:

[0100] Since there are both single-well nitrogen throughput and single-well / multi-well nitrogen drive in the reservoir unit; and some gas injection wells firstly perform single-well nitrogen throughput and then increase the gas injection volume for gas drive, therefore, wells with relatively closed boundaries and independent pressure systems are selected as single-well nitrogen injection wells (see the single-well nitrogen injection throughput well selection plan described above for details); those with good connectivity are selected as single-well / multi-well well groups (see the single-well nitrogen drive plan or multi-well nitrogen drive well selection plan described above for details).

[0101] Step S104, determining the injection and production parameters of the injection and production well group to obtain an injection and production plan for the oil reservoir.

[0102] In this embodiment, when the injection-production scheme type is a single-well nitrogen injection huff-and-puff scheme, determining the injection-production parameters of the injection-production well group to obtain the injection-production scheme of the oil reservoir includes:

[0103] The injection and production parameters of the injection and production well group are determined based on a pre-established chart to obtain an injection and production plan for the oil reservoir; wherein the chart reflects the corresponding relationship between the fracture and cave genesis type of the oil reservoir and the injection and production parameters.

[0104] In this embodiment, the injection and production parameters are determined according to the genesis type of fractures and caves in the oil reservoir in combination with the nitrogen injection and production parameter chart for a single well in the fracture-cave oil reservoir. Specifically, the actual gas injection parameters are determined based on the relationship chart between the periodic gas injection volume, gas injection rate, liquid production intensity, well soaking time, etc. and the remaining recoverable reserves of the three types of fracture and cave genesis: surface karst, underground river karst, and fault-controlled karst.

[0105] In this embodiment, when the injection-production scheme type is a single-well nitrogen drive scheme, a multi-well nitrogen drive scheme, or a unit nitrogen injection scheme, determining the injection-production parameters of the injection-production well group to obtain the injection-production scheme of the oil reservoir includes:

[0106] Based on the pre-established geological model of the injection-production well group and multiple groups of preset injection-production parameters, the oil-increasing effect under each group of the preset injection-production parameters is simulated and calculated; based on the oil-increasing effect, target injection-production parameters are selected from the multiple groups of preset injection-production parameters as the injection-production parameters of the injection-production well group.

[0107] Among them, the injection and production parameters mainly include: injection and production location, gas injection method, gas injection volume, gas injection speed, concomitant water injection volume, gas injection timing, liquid production intensity, well holding time, injection and production ratio, etc.

[0108] Specifically, we first establish geological models of single wells and well groups, and simulate the underground flow phase state and production history fitting of nitrogen injection. Then, we preset multiple sets of injection and production parameters, simulate and calculate the oil-increasing effect under different injection and production parameters, and determine the set of injection and production parameters with the best oil-increasing effect, that is, the largest oil-increasing amount, so as to determine the optimal nitrogen injection development plan.

[0109] Furthermore, in this embodiment, the method further includes: evaluating the economic benefits of the injection and production scheme of the oil reservoir based on a pre-established economic evaluation model.

[0110] Specifically, an economic evaluation model is established by comprehensively considering economic parameters and contract financial and tax clauses, and parameters such as the total investment rate of return and investment payback period of the optimal nitrogen injection development plan are calculated to evaluate the economic benefits of the optimal nitrogen injection development plan.

[0111] The method for designing an injection and production scheme for an oil reservoir provided in an embodiment of the present invention can obtain the distribution information of the remaining oil in the oil reservoir by performing numerical simulation of the three-dimensional geological model of the oil reservoir to be designed; based on the remaining oil distribution information, the distribution information of the wells already drilled in the oil reservoir and the basic characteristics of the wells already drilled, the injection and production well group can be determined; after the injection and production parameters of the injection and production well group are determined, the injection and production scheme for the oil reservoir can be obtained. Compared with the prior art, the present invention provides a set of systematic and complete oil reservoir injection and production scheme designs, which can be automatically executed on electronic equipment / electronic terminals, so that the injection and production scheme for the oil reservoir to be designed can be accurately and effectively determined, thereby greatly improving the efficiency of oil reservoir injection and production work.

[0112] Embodiment 2

[0113] This embodiment takes the SY unit of the domestic Tahe Oilfield and the actual specific operation process of the operators as an example to describe in detail the reservoir injection and production scheme design method.

[0114] like Figure 2 As shown, the method described in this embodiment includes:

[0115] Step S201, determining the research objectives based on the type of reservoir to be designed, the current development stage and historical development information;

[0116] In this embodiment, determining the research objective is to determine the type of injection and production scheme. There are four specific types of injection and production schemes described in this embodiment, namely: single well nitrogen injection and huff and puff scheme, single well nitrogen flooding scheme, multi-well nitrogen flooding scheme and unit nitrogen injection scheme.

[0117] The SY unit is located in the Upper Ordovician covered area, dominated by the fault-controlled karst of the middle Caledonian period, and is a typical fault-karst reservoir. The unit has a geological reserve of 5.09 million tons, a cumulative oil production of 840,000 tons, and a calibrated recovery rate of 16.4%. At present, the comprehensive water content is 55%, and the unit is in the medium-to-high water content development stage. The unit has successively implemented unit water injection development and single-well nitrogen injection huff and puff. At present, water channeling has occurred in the main water-driven effective wells, and the water injection effect has deteriorated. The gas drive of the well group is unidirectionally effective, and the cumulative oil increase of gas injection is 3,200 tons. The unit gas drive has initially achieved results. On the whole, the unit is in the stage of water injection adjustment and trial gas injection. Based on the above information, the research target is determined to be the unit nitrogen injection scheme.

[0118] Step S202, establishing a three-dimensional geological model of the oil reservoir to be designed, and performing oil reservoir evaluation based on the three-dimensional geological model;

[0119] In this embodiment, based on the historical seismic data of the oil reservoir to be designed, the type of fracture-vuggy reservoir, logging data, core experiment data and drilling experiment data, the cave information, dissolution hole information, fracture information and fracture space distribution information of the oil reservoir are obtained; based on the cave information, dissolution hole information, fracture information and fracture space distribution information of the oil reservoir, a cave model, a dissolution hole model and a fracture model are established respectively; the cave model, the dissolution hole model and the fracture model are merged to obtain a three-dimensional geological model of the oil reservoir.

[0120] Specifically, the above-mentioned historical seismic data can be obtained through the seismic data of the oil reservoir, and the logging data can be obtained through various logging methods such as imaging logging. The historical seismic data, fracture-cavity reservoir type, logging data, core test data and drilling test data are used to comprehensively describe the spatial distribution and physical properties of caves, dissolved pores, faults and fractures. A hierarchical classification modeling method is adopted to establish cave models, dissolved pore models and fault models of different scales respectively, and the above-mentioned different types of models are integrated into a three-dimensional geological model of the oil reservoir to be designed. In this embodiment, the three-dimensional geological model is a three-dimensional geological model of a fracture-cavity carbonate reservoir. Relying on this three-dimensional geological model, key parameters such as the fracture-cavity type, connectivity, physical properties and heterogeneity of the fracture-cavity body in the oil reservoir can be determined.

[0121] In the actual operation, through the multi-type data information such as "seismic profile", "drilling" and "well logging", the development scale of the karst-type reservoir within 0-60m below the unconformity surface of unit T74 is comprehensively described. The results show that the development scale of the karst-type reservoir within 0-60m is relatively large, while it is scattered within 60m-120m. Through the characterization of the curvature ant body, it is revealed that the unit has two groups of faults in the northeast and northwest, such as Figure 3 Using the classification modeling method, the cave model, the dissolution hole model and the fracture model are established respectively, and these models are integrated to form a three-dimensional geological model of the reservoir, as shown in Figure 4 shown.

[0122] Afterwards, the three-dimensional geological model of the reservoir is numerically simulated according to the composite medium model. Specifically, numerical simulation is carried out based on the type, scale and flow classification of each reservoir body in the reservoir to reflect the fluid flow characteristics in large fractures and large caves in the reservoir, quantitatively characterize the type, occurrence mode, spatial distribution characteristics and different types of remaining reserves of the remaining oil after water flooding, comprehensively evaluate the remaining oil in the reservoir after water flooding, and obtain the remaining oil distribution information in the reservoir.

[0123] Relying on the above-mentioned three-dimensional geological model, the key parameters such as "well-controlled remaining reserves", "cavern top remaining reserves", "residual hill remaining reserves" and "remaining reserves within 60m below the top of the structure" are quantitatively calculated mainly through the numerical simulation method of fracture-cavern oil reservoirs, so as to quantitatively evaluate the nitrogen injection potential of the target block.

[0124] According to the above method, the static geological reserves of SY unit are 5.09 million tons, and the remaining reserves after water flooding are 4.25 million tons. The remaining potential is concentrated in the southern part of the unit, and is mainly composed of cave roof attic oil. It is determined that the G1 and G2 well groups in the southern part of the unit are the sweet spots for nitrogen flooding, with great gas injection potential.

[0125] Step S203, determining the injection-production well group based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells;

[0126] Since the research target determined in this embodiment (i.e. the type of injection and production scheme determined) is a unit nitrogen injection scheme, the injection and production well group is determined based on the well selection method described in Embodiment 1 when the injection and production scheme type is a unit nitrogen injection scheme:

[0127] Since there are both single-well nitrogen throughput and single-well / multi-well nitrogen drive in the reservoir unit; and some gas injection wells firstly perform single-well nitrogen throughput and then increase the gas injection volume for gas drive, therefore, wells with relatively closed boundaries and independent pressure systems are selected as single-well nitrogen injection wells (see the single-well nitrogen injection throughput well selection plan described in Example 1 for details); those with better connectivity are selected as single-well / multi-well well groups (see the single-well nitrogen drive plan or multi-well nitrogen drive well selection plan described in Example 1 for details).

[0128] According to the above well selection method, in this embodiment, the current daily oil production of G1 well and G2 well is less than 3 tons / day, and the water content is more than 97%, as shown in the following Table 1. And the tracer monitoring shows that the effective well corresponding to G1 well is P1 well, with a well spacing of 612m and the agent is seen in 16 days. The effective well corresponding to G2 well is P2 well, with a well spacing of 552m and the agent is seen in 70 days. According to the principle of "low production and high water content", G1 well and G2 well are determined as gas injection wells, and P1 and P2 wells are determined as oil production wells.

[0129] Table 1

[0130]

[0131] Step S204, determining the injection and production parameters of the injection and production well group to obtain an injection and production plan for the oil reservoir to be designed;

[0132] Since the research target (i.e. the type of injection-production scheme determined) determined in this embodiment is a unit nitrogen injection scheme, the injection-production parameters of the injection-production well group are determined to obtain the injection-production scheme of the oil reservoir, including:

[0133] Based on the pre-established geological model of the injection-production well group and multiple groups of preset injection-production parameters, the oil-increasing effect under each group of the preset injection-production parameters is simulated and calculated; based on the oil-increasing effect, target injection-production parameters are selected from the multiple groups of preset injection-production parameters as the injection-production parameters of the injection-production well group.

[0134] Among them, the injection and production parameters mainly include: injection and production location, gas injection method, gas injection volume, gas injection speed, concomitant water injection volume, gas injection timing, liquid production intensity, well holding time, injection and production ratio, etc.

[0135] Specifically, firstly, the geological model of single well and well group is established, and the underground flow phase state simulation and production history matching of nitrogen injection are carried out; then, multiple groups of injection and production parameters are preset, and the oil increase effect under different injection and production parameters is simulated and calculated, and the group of injection and production parameters with the best oil increase effect, that is, the largest oil increase, is determined to determine the optimal nitrogen injection development plan. Table 2 shows the actual injection and production parameters of G1 well, G2 well, P1 well and P2 well determined according to the above method:

[0136] Table 2

[0137]

[0138]

[0139] Step S205, preparing a unit nitrogen injection development plan;

[0140] In actual operation, the gas injection development plan needs to be specifically compiled. In this embodiment, the nitrogen injection development plan for fracture-cavity reservoirs needs to meet the following compilation requirements:

[0141] ① Re-understanding of development geology

[0142] It includes logging identification of fracture-cavity reservoirs, detailed seismic description of fracture-cavity reservoirs, fracture-cavity distribution and oil-water relationship, three-dimensional fracture-cavity geological modeling, and geological reserve re-evaluation.

[0143] ②Evaluation of development effect and nitrogen injection potential

[0144] It includes development status, early water injection effect evaluation, energy status, connectivity evaluation, recoverable reserves and recovery rate analysis, gas injection potential evaluation, etc.

[0145] ③ Numerical simulation of nitrogen injection in fracture-cavity reservoirs to evaluate the remaining oil potential between wells and cave tops

[0146] It includes reservoir model import, nitrogen injection gas phase equilibrium calculation data, phase permeability curve, rock data, initial reservoir conditions, completion and measures, production history fitting, remaining oil distribution characteristics, remaining oil potential, etc.

[0147] ④ Design of gas injection development plan and prediction of development indicators for fracture-cavity reservoirs

[0148] The design of gas injection development plan includes injection and production well pattern design, injection and production layer design, and injection and production parameter design; the development index prediction includes oil increase, water cut decline, energy retention, and gas-to-oil ratio. Form no less than 3 sets of development plans. Compare the gas injection oil increase effect of each plan and determine the recommended development plan for nitrogen injection.

[0149] Specifically, in this embodiment, the unit geology re-recognition, development effect and comprehensive evaluation of gas injection potential are used as the basis. Combined with numerical simulation, quantitative evaluation of the remaining potential between wells and cave tops, prediction of gas injection oil increase, water content reduction, etc., three development plans are formed. Due to the uncertainty of the reservoir, the gas injection oil increase effect of each plan is compared, and the optimal nitrogen injection development plan is finally determined, as shown in Table 3 below. In this optimal development plan, the development index prediction curves of P1 well and P2 well are as follows Figure 5A and Figure 5B shown.

[0150] Table 3

[0151]

[0152] Step S206, based on the pre-established economic evaluation model, the economic benefits of the injection and production scheme of the oil reservoir are evaluated.

[0153] In this embodiment, the economic evaluation model is built by comprehensively considering the economic parameters and the fiscal and taxation clauses of the contract, and the total investment rate of return and investment payback period of the optimal nitrogen injection development plan are calculated. The optimal nitrogen injection development plan is evaluated to have a cumulative increase of 15,800 tons of oil and a profit of 49 million yuan.

[0154] It should be noted that the second embodiment is a specific implementation method described from the perspective of an operator, and the above method flow can be implemented by automatically executing a corresponding computer program through an electronic terminal.

[0155] The method for designing an injection and production scheme for an oil reservoir provided in an embodiment of the present invention can obtain the distribution information of the remaining oil in the oil reservoir by performing numerical simulation of the three-dimensional geological model of the oil reservoir to be designed; based on the remaining oil distribution information, the distribution information of the wells already drilled in the oil reservoir and the basic characteristics of the wells already drilled, the injection and production well group can be determined; after the injection and production parameters of the injection and production well group are determined, the injection and production scheme for the oil reservoir can be obtained. Compared with the prior art, the present invention provides a set of systematic and complete oil reservoir injection and production scheme designs, which can be automatically executed on electronic equipment / electronic terminals, so that the injection and production scheme for the oil reservoir to be designed can be accurately and effectively determined, thereby greatly improving the efficiency of oil reservoir injection and production work.

[0156] This embodiment specifically forms a design method for nitrogen injection development plan for fracture-cavity carbonate reservoirs, which is a systematic and complete design method. It aims to propose the optimal nitrogen injection plan by determining the research objectives, clarifying the adaptability of nitrogen injection, determining nitrogen injection wells and supporting parameters.

[0157] Embodiment 3

[0158] Corresponding to the above method embodiment, the present invention also provides a reservoir injection and production scheme design system, such as Figure 6 As shown, the system comprises:

[0159] The three-dimensional modeling module 301 is used to establish a three-dimensional geological model of the reservoir based on the acquired geological information of the reservoir to be designed; the three-dimensional geological model includes the distribution information of the wells drilled in the reservoir;

[0160] Numerical simulation module 302, used to perform oil reservoir numerical simulation on the three-dimensional geological model to obtain the remaining oil distribution information in the oil reservoir;

[0161] An injection-production well group determination module 303 is used to determine an injection-production well group based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells;

[0162] The injection-production parameter determination module 304 is used to determine the injection-production parameters of the injection-production well group to obtain an injection-production plan for the oil reservoir.

[0163] Furthermore, if Figure 7 As shown, the system described in this embodiment also includes:

[0164] The injection-production scheme type determination module 305 is used to determine the injection-production scheme type based on the type of the oil reservoir, the current development stage and the historical development information.

[0165] In this embodiment, when the injection-production scheme type is a single-well nitrogen injection and huff-and-puff scheme, the injection-production well group determination module 303 includes:

[0166] A first well-to-be-selected determining unit is used to determine a plurality of wells to be selected based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells; wherein the wells to be selected are gas-injected wells;

[0167] A well selection parameter determination unit, configured to determine a well selection parameter corresponding to each of the wells to be selected based on the geological information, construction information and gas injection information of the wells to be selected;

[0168] A prediction unit, used to use each group of the well selection parameters as an input of a pre-trained gas injection oil increase prediction model to predict the oil increase effect corresponding to each of the wells to be selected;

[0169] The first selection unit is used to select a target well from the multiple wells to be selected as the injection and production well group based on the oil-increasing effect.

[0170] In this embodiment, when the injection-production scheme type is a single-well nitrogen drive scheme or a multi-well nitrogen drive scheme, the injection-production well group determination module 303 includes:

[0171] A second well-to-be-selected determining unit is used to determine a plurality of groups of wells to be selected based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells; wherein the wells to be selected are water-injected wells;

[0172] A target well group determination unit, configured to determine a target well group based on connectivity between wells in each group of the wells to be selected;

[0173] The second selection unit is used to determine the gas injection wells and oil production wells in the target well group based on the tracer monitoring data obtained in advance to determine the injection and production well group.

[0174] In this embodiment, when the injection and production scheme type is a single-well nitrogen injection and huff-and-puff scheme, the injection and production parameter determination module 304 is used to determine the injection and production parameters of the injection and production well group based on a pre-established map to obtain the injection and production scheme of the oil reservoir; wherein the map reflects the correspondence between the fracture and cave genesis type of the oil reservoir and the injection and production parameters.

[0175] In this embodiment, when the injection-production scheme type is a single-well nitrogen drive scheme, a multi-well nitrogen drive scheme, or a unit nitrogen injection scheme, the injection-production parameter determination module 304 includes:

[0176] A simulation calculation unit, used for simulating and calculating the oil-increasing effect under each set of preset injection-production parameters based on the pre-established geological model of the injection-production well group and multiple sets of preset injection-production parameters;

[0177] The third selection unit is used to select target injection-production parameters from the multiple groups of preset injection-production parameters as the injection-production parameters of the injection-production well group based on the oil-increasing effect.

[0178] In this embodiment, the geological information of the oil reservoir to be designed includes: historical seismic data, fracture-cavity reservoir type, well logging data, core test data and drilling test data of the oil reservoir to be designed; the three-dimensional modeling module 301 includes:

[0179] An information acquisition unit, for acquiring cave information, dissolved hole information, fracture information and fracture spatial distribution information of the oil reservoir based on the historical seismic data, fracture-cavity reservoir type, well logging data, core test data and drilling test data;

[0180] A model building unit, used to build a cave model, a dissolution hole model and a fracture model respectively based on the cave information, dissolution hole information, fracture information and fracture space distribution information of the oil reservoir;

[0181] The model fusion unit is used to fuse the cave model, the dissolution hole model and the fracture model to obtain a three-dimensional geological model of the oil reservoir.

[0182] Furthermore, the system described in this embodiment also includes:

[0183] A model correction unit is used to correct the three-dimensional geological model based on the dynamic data of a single well drilled in the oil reservoir to obtain a corrected three-dimensional geological model; then,

[0184] The numerical simulation module 302 is also used to perform reservoir numerical simulation on the corrected three-dimensional geological model to obtain the remaining oil distribution information in the reservoir.

[0185] Furthermore, if Figure 7 As shown, the system described in this embodiment also includes:

[0186] The economic benefit evaluation module 306 is used to evaluate the economic benefit of the injection and production scheme of the oil reservoir based on a pre-established economic evaluation model.

[0187] The working principle, work flow and other contents related to the specific implementation methods of the above-mentioned device can be found in the specific implementation methods of the oil reservoir injection and production scheme design method provided by the present invention, and the same technical contents will not be described in detail here.

[0188] The oil reservoir injection and production scheme design system provided by the embodiment of the present invention can obtain the remaining oil distribution information in the oil reservoir by performing oil reservoir numerical simulation on the established three-dimensional geological model of the oil reservoir to be designed; based on the remaining oil distribution information, the distribution information of the wells already drilled in the oil reservoir and the basic characteristics of the wells already drilled, the injection and production well group can be determined; after determining the injection and production parameters of the injection and production well group, the injection and production scheme of the oil reservoir can be obtained. Compared with the prior art, the present invention provides a set of systematic and complete oil reservoir injection and production scheme design, which can be automatically executed on electronic equipment / electronic terminals, so that the injection and production scheme of the oil reservoir to be designed can be accurately and effectively determined, thereby greatly improving the efficiency of oil reservoir injection and production work.

[0189] Embodiment 4

[0190] According to an embodiment of the present invention, a storage medium is further provided, on which a program code is stored. When the program code is executed by a processor, the method for designing an oil reservoir injection and production plan as described in any one of the above embodiments is implemented.

[0191] The working principle, workflow and other contents related to the specific implementation methods of the method can be found in the specific implementation methods of the reservoir injection and production scheme design method provided by the present invention, and the same technical contents will not be described in detail here.

[0192] Embodiment 5

[0193] According to an embodiment of the present invention, there is also provided an electronic device, which includes a memory and a processor, wherein the memory stores a program code that can be run on the processor, and when the program code is executed by the processor, the method for designing an oil reservoir injection and production plan as described in any of the above embodiments is implemented.

[0194] The working principle, workflow and other contents related to the specific implementation methods of the method can be found in the specific implementation methods of the reservoir injection and production scheme design method provided by the present invention, and the same technical contents will not be described in detail here.

[0195] The method, system, storage medium and electronic device for designing an injection and production scheme for an oil reservoir provided by the embodiment of the present invention can obtain the distribution information of the remaining oil in the oil reservoir by performing numerical simulation of the three-dimensional geological model of the oil reservoir to be designed; based on the remaining oil distribution information, the distribution information of the wells already drilled in the oil reservoir and the basic characteristics of the wells already drilled, the injection and production well group can be determined; after the injection and production parameters of the injection and production well group are determined, the injection and production scheme of the oil reservoir can be obtained. Compared with the prior art, the present invention provides a set of systematic and complete oil reservoir injection and production scheme designs, which can be automatically executed on electronic equipment / electronic terminals, so that the injection and production scheme of the oil reservoir to be designed can be accurately and effectively determined, thereby greatly improving the efficiency of oil reservoir injection and production work.

[0196] According to the different development stages of the reservoir and the main problems faced, this design method designs a total of four types of development plans: "single well nitrogen injection and huff and puff", "single well nitrogen drive", "multi-well nitrogen drive" and "unit nitrogen injection plan". First, based on the static geological evaluation of the reservoir, the distribution of fractures and caves, the evaluation of remaining oil and the evaluation of gas injection potential are carried out to clarify the adaptability and potential of nitrogen injection. Secondly, by determining the wells to be selected, calculating the well selection parameters, predicting the oil increase effect of nitrogen injection, and comprehensively analyzing the well selection, the nitrogen injection wells and oil production wells are determined. For single well nitrogen injection and huff and puff, the reasonable injection and production parameters are determined by the plate method. For nitrogen drive, the supporting parameters of nitrogen injection wells and oil production wells are optimized by the modeling-numerical modeling method. Finally, a comparative analysis of the plans is carried out to determine the optimal plan and comprehensively evaluate the economic benefits of the plans. Therefore, the present invention is a systematic and complete design plan for reservoir injection and production plans, which can accurately and effectively determine the injection and production plans of the reservoirs to be designed, thereby greatly improving the efficiency of reservoir injection and production work.

[0197] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed.

[0198] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the embodiments of the present invention.

[0199] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0200] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for enabling an electronic device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0201] Although the embodiments disclosed in the present invention are as above, the contents described are only embodiments adopted for facilitating the understanding of the present invention and are not intended to limit the present invention. Any technician in the technical field to which the present invention belongs can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed in the present invention, but the protection scope of the present invention shall still be subject to the scope defined in the attached claims.

Claims

1. A method for designing an oil reservoir injection and production plan, characterized in that: The method comprises: Based on the acquired geological information of the oil reservoir to be designed, a three-dimensional geological model of the oil reservoir is established; the three-dimensional geological model includes distribution information of the wells drilled in the oil reservoir; Performing reservoir numerical simulation on the three-dimensional geological model to obtain the remaining oil distribution information in the reservoir; Determine an injection-production well group based on the remaining oil distribution information, the distribution information of the drilled wells and pre-acquired basic characteristics of the drilled wells; Determining the injection and production parameters of the injection and production well group to obtain an injection and production plan for the oil reservoir; Wherein, when the injection-production scheme type is a single-well nitrogen injection and huff-and-puff scheme, determining the injection-production well group based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells includes: Based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells, a plurality of wells to be selected are determined; wherein the wells to be selected are gas-injected wells; Determining well selection parameters corresponding to each of the wells to be selected based on geological information, construction information and gas injection information of the wells to be selected; Using each group of the well selection parameters as the input of a pre-trained gas injection oil increase prediction model to predict the oil increase effect corresponding to each of the wells to be selected; Based on the oil-increasing effect, selecting a target well from the plurality of candidate wells as the injection-production well group; When the injection-production scheme type is a single-well nitrogen drive scheme or a multi-well nitrogen drive scheme, determining the injection-production well group based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells includes: Based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells, a plurality of groups of wells to be selected are determined; wherein the wells to be selected are water-injected wells; Determining a target well group based on connectivity between wells in each group of the candidate wells; Based on the tracer monitoring data acquired in advance, determining the gas injection wells and the oil production wells in the target well group to determine the injection and production well group; When the injection-production scheme type is a single-well nitrogen injection huff-and-puff scheme, determining the injection-production parameters of the injection-production well group to obtain the injection-production scheme of the oil reservoir includes: Determining the injection and production parameters of the injection and production well group based on a pre-established chart to obtain an injection and production plan for the oil reservoir; wherein the chart reflects the corresponding relationship between the fracture and cave genesis type of the oil reservoir and the injection and production parameters; When the injection-production scheme type is a single-well nitrogen drive scheme, a multi-well nitrogen drive scheme, or a unit nitrogen injection scheme, determining the injection-production parameters of the injection-production well group to obtain the injection-production scheme of the oil reservoir includes: Based on the pre-established geological model of the injection-production well group and multiple groups of preset injection-production parameters, simulate and calculate the oil-increasing effect under each group of the preset injection-production parameters; Based on the oil-increasing effect, target injection-production parameters are selected from the multiple groups of preset injection-production parameters as the injection-production parameters of the injection-production well group.

2. The method for designing an oil reservoir injection and production plan according to claim 1, characterized in that: Before determining the injection-production well group based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells, the method further includes: The type of injection and production plan is determined based on the type of reservoir, the current development stage and historical development information.

3. The method for designing an oil reservoir injection and production plan according to claim 1, characterized in that: The geological information of the oil reservoir to be designed includes: historical seismic data, fracture-cavity reservoir type, well logging data, core test data and drilling test data of the oil reservoir to be designed; the three-dimensional geological model of the oil reservoir is established based on the acquired geological information of the oil reservoir to be designed, including: Based on the historical seismic data, fracture-cavity reservoir types, well logging data, core test data and drilling test data, the karst cave information, dissolution hole information, fault information and fracture spatial distribution information of the oil reservoir are obtained; Based on the karst cave information, karst pore information, fault information and fracture spatial distribution information of the oil reservoir, a karst cave model, a karst pore model and a fault model are established respectively; The cave model, the dissolution pore model and the fracture model are integrated to obtain a three-dimensional geological model of the oil reservoir.

4. The method for designing an oil reservoir injection and production plan according to claim 3, characterized in that: The method further comprises: Based on the dynamic data of a single well drilled in the oil reservoir, the three-dimensional geological model is corrected to obtain a corrected three-dimensional geological model; The performing of reservoir numerical simulation on the three-dimensional geological model to obtain the remaining oil distribution information in the reservoir includes: The corrected three-dimensional geological model is subjected to reservoir numerical simulation to obtain the remaining oil distribution information in the reservoir.

5. The method for designing an oil reservoir injection and production plan according to claim 1, characterized in that: The method further comprises: Based on a pre-established economic evaluation model, the economic benefits of the injection and production scheme of the oil reservoir are evaluated.

6. A system for designing an oil reservoir injection and production plan for implementing the oil reservoir injection and production plan design method according to any one of claims 1 to 5, characterized in that: The system comprises: A three-dimensional modeling module, used to establish a three-dimensional geological model of the reservoir based on the acquired geological information of the reservoir to be designed; the three-dimensional geological model includes the distribution information of the wells drilled in the reservoir; A numerical simulation module, used to perform numerical simulation of the oil reservoir on the three-dimensional geological model to obtain the remaining oil distribution information in the oil reservoir; An injection-production well group determination module is used to determine the injection-production well group based on the remaining oil distribution information, the distribution information of the drilled wells and the pre-acquired basic characteristics of the drilled wells; The injection-production parameter determination module is used to determine the injection-production parameters of the injection-production well group to obtain the injection-production plan of the oil reservoir.

7. A storage medium having a program code stored thereon, characterized in that: When the program code is executed by a processor, the method for designing an oil reservoir injection and production plan according to any one of claims 1 to 5 is implemented.

8. An electronic device, characterized in that: The electronic device includes a memory and a processor. The memory stores program codes that can be run on the processor. When the program codes are executed by the processor, the method for designing an oil reservoir injection and production plan according to any one of claims 1 to 5 is implemented.

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