Method, device and equipment for determining oil reservoir flooding conversion opportunity based on oil saturation

Abstract

The invention provides a method, device and equipment for determining the oil reservoir transfer opportunity based on oil saturation. The method comprises the steps that the oil saturation of each target well group is determined according to steam huff and puff production data of multiple target well groups; determining the oil layer heat storage amount when the same steam injection amount is injected into each target well group at different historical mining time; determining a relational graph between the oil saturation and the oil layer heat utilization rate according to the heat storage capacity of each oil layer; according to the relational graph between the oil saturation and the oil layer heat utilization rate, the optimal opportunity of oil reservoir to steam drive is determined; thus, by researching the oil layer heat utilization rate under different oil saturation conditions in the steam huff and puff process of various types of oil wells, different oil saturation and the oil layer heat utilization rate are fitted, and the oil saturation critical value required by oil reservoir steam flooding is reversely deduced according to the fitted relational graph; according to the residual saturation critical value, the optimal opportunity of oil reservoir steam drive conversion is determined, the determination precision of the steam drive conversion opportunity is improved, and the overall development effect of an oil field is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of crude oil development, and in particular to a method, a device and equipment for determining the timing of reservoir flooding based on oil saturation. Background Art

[0002] Heavy oil steam injection development belongs to the secondary development of crude oil and is a development technology for thermal recovery of heavy oil. Steam contains a large amount of latent heat, and steam injection has been widely used in the petroleum industry. There are two technologies used for steam injection: one is periodic steam injection and the other is steam flooding. When the periodic steam injection reaches the economic limit, there will be characteristics such as accelerated decline in crude oil production, decreased oil production rate, decreased production-injection ratio, poor development effect, and poor economic benefits. Therefore, when the periodic steam injection enters the economic limit of the injection, it is necessary to determine whether to enter the tertiary oil recovery, that is, the steam flooding stage. However, the steam flooding method involves the establishment of well networks, the improvement of ground engineering construction and supporting oil production engineering, and is a systematic and huge project. Before switching to steam flooding, it is necessary to make an accurate judgment on the economic benefits and production evaluation to ensure that the steam flooding stage completes the indicators of reservoir recovery and economic benefits.

[0003] That is to say, before switching to steam flooding, it is necessary to determine the best time to switch to steam flooding and determine a reasonable switching plan. However, the existing technology cannot accurately determine the best time to switch to steam flooding, which in turn affects the efficient use of thermal energy and the overall development effect of the oil field. Summary of the invention

[0004] In response to the problems existing in the prior art, the embodiments of the present invention provide a method, device and equipment for determining the timing of oil reservoir conversion based on oil saturation, so as to solve or partially solve the technical problem that the prior art cannot accurately determine the timing of conversion to steam drive, thereby affecting the overall development effect of the oil field.

[0005] A first aspect of the present invention provides a method for determining the timing of reservoir flooding based on oil saturation, the method comprising:

[0006] Obtain production data of multiple target well groups during steam stimulation production;

[0007] Determine the oil saturation of each target well group according to the production data;

[0008] Determine the heat storage of the oil layer when the same steam injection amount is injected into each target well group at different historical production times;

[0009] Determine a relationship diagram between oil saturation and oil layer thermal utilization rate according to the heat storage of each oil layer;

[0010] The best time to switch to steam flooding in the oil reservoir is determined based on the relationship diagram between the oil saturation and the thermal utilization rate of the oil layer.

[0011] In the above solution, the production data includes: production, temperature and perforation parameters; and determining the oil saturation of the target well group according to the production data includes:

[0012] dividing the production of the target well group into different production layers according to the perforation parameters;

[0013] Determine the recovery ratio of each production layer;

[0014] Determine the remaining oil saturation of each production layer according to the original oil saturation of the production layer and the recovery ratio of each production layer;

[0015] The target production layer of the target well group is determined, and the residual oil saturation of the target production layer is determined based on the residual oil saturation of each production layer; the residual oil saturation of the target production layer is the oil saturation of the target well group.

[0016] In the above scheme, the determination of the heat storage amount of the oil layer injected with the same steam injection amount at different historical production times for each target well group includes:

[0017] For any historical production time, the injected oil layer heat content of each target well group is determined according to the steam injection volume, and the output heat of each target well group is determined according to the produced liquid temperature;

[0018] The oil layer heat storage amount is determined according to the injected oil layer heat content and the produced heat; the oil layer heat storage amount is the difference between the injected oil layer heat content and the produced heat.

[0019] In the above scheme, the step of determining the injected oil layer heat content of each target well group according to the steam injection amount includes:

[0020] determining a total injected heat according to the gas injection amount;

[0021] Determine the heat loss along the steam injection process based on the temperature change of the steam;

[0022] The injected oil layer heat content of the target well group is determined according to the total injected heat and the heat loss, and the injected oil layer heat content is the difference between the total injected heat and the heat loss.

[0023] In the above scheme, the relationship diagram between oil saturation and oil layer heat utilization rate determined according to the amount of heat stored in the oil layer includes:

[0024] Determine the oil layer heat utilization rate of each target well group according to the oil layer heat storage;

[0025] Curve fitting is performed on the oil layer thermal utilization rate and oil saturation of each target well group to obtain a relationship diagram between the oil saturation and the oil layer thermal utilization rate.

[0026] In the above scheme, the optimal time to switch to steam flooding in the oil reservoir is determined according to the relationship diagram between the oil saturation and the thermal utilization rate of the oil layer, including:

[0027] Performing inflection point detection on the relationship diagram between the oil saturation and the thermal utilization rate of the oil layer using an inflection point detection function to obtain a turning point in the relationship diagram between the oil saturation and the thermal utilization rate of the oil layer;

[0028] determining the oil saturation corresponding to the turning point as the target oil saturation;

[0029] The optimal time for switching the oil reservoir to steam flooding is determined according to the target oil saturation, and the optimal time is the time corresponding to when the remaining oil saturation of the oil reservoir is the target oil saturation.

[0030] A second aspect of the present invention provides a device for determining the timing of reservoir flooding based on oil saturation, the device comprising:

[0031] An acquisition unit, used for acquiring production data of multiple target well groups during the steam stimulation production process;

[0032] The first determination unit is used to determine the oil saturation of each target well group according to the production data; determine the oil layer heat storage when the same steam injection amount is injected into each target well group at different historical production times; and determine the relationship diagram between the oil saturation and the oil layer heat utilization rate according to the oil layer heat storage;

[0033] The second determination unit is used to determine the best time to switch the oil reservoir to steam flooding according to the relationship diagram between the oil saturation and the thermal utilization rate of the oil layer.

[0034] In the above solution, the first determining unit is specifically used for:

[0035] Determine the oil layer heat utilization rate of each target well group according to the oil layer heat storage;

[0036] Curve fitting is performed on the oil layer thermal utilization rate and oil saturation of each target well group to obtain a relationship diagram between the oil saturation and the oil layer thermal utilization rate.

[0037] According to a third aspect of the present invention, a computer-readable storage medium is provided, on which a computer program is stored, and when the program is executed by a processor, the steps of any one of the methods described in the first aspect are implemented.

[0038] According to a fourth aspect of the present invention, a computer device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps of any one of the methods described in the first aspect are implemented.

[0039] The present invention provides a method, device and equipment for determining the timing of oil reservoir conversion drive based on oil saturation, the method comprising: obtaining production data of multiple target well groups during steam stimulation production; determining the oil saturation of each target well group according to the production data; determining the oil layer heat storage amount when the same steam injection amount is injected into each target well group at different historical production times; determining the relationship diagram between oil saturation and oil layer heat utilization rate according to the heat storage amount of each oil layer; determining the best timing of oil reservoir conversion to steam drive according to the relationship diagram between oil saturation and oil layer heat utilization rate; thus, the present invention studies the oil layer heat utilization rate under different oil saturations during steam stimulation of various types of oil wells, fits different oil saturations and oil layer heat utilization rates, and inversely deduces the critical value of oil saturation required for oil reservoir conversion to steam drive according to the fitted relationship diagram, so that the conversion drive timing is quantified according to the oil saturation, and finally the best timing of oil reservoir conversion to steam drive can be determined according to the residual saturation of the oil reservoir, thereby improving the determination accuracy of the steam drive timing, and further improving the overall development effect of the oil field. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] By reading the detailed description of the preferred embodiment below, various other advantages and benefits will become clear to those of ordinary skill in the art. The accompanying drawings are only used for the purpose of illustrating the preferred embodiment and are not considered to be limitations of the present invention. In addition, the same reference symbols are used to represent the same components throughout the accompanying drawings.

[0041] In the attached picture:

[0042] Figure 1 A schematic flow chart of a method for determining the timing of reservoir flooding based on oil saturation according to an embodiment of the present invention is shown;

[0043] Figure 2 It shows a diagram of oil saturation and oil layer heat storage according to one embodiment of the present invention;

[0044] Figure 3 It shows the temperature field and steam cavity expansion diagram of a target well group with an oil saturation of 40% according to one embodiment of the present invention;

[0045] Figure 4 It shows the temperature field and steam cavity expansion diagram of the target well group with an oil saturation of 70% according to one embodiment of the present invention;

[0046] Figure 5A diagram showing the relationship between oil saturation and oil layer thermal utilization rate according to an embodiment of the present invention is shown;

[0047] Figure 6 A schematic diagram of the structure of a device for determining the timing of reservoir flooding based on oil saturation according to an embodiment of the present invention is shown;

[0048] Figure 7 A schematic diagram of the structure of a computer device according to an embodiment of the present invention is shown;

[0049] Figure 8 A schematic diagram of the structure of a computer-readable storage medium according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0050] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0051] In order to better understand the technical solution of the present invention, the steam throughput technology is first introduced here.

[0052] Steam stimulation is the most commonly used method in heavy oil production and is also the best thermal recovery method for industrial application. Steam stimulation is also called steam stimulation or cyclic steam injection. Steam stimulation is a method of increasing the production of heavy oil by injecting a certain amount of steam into the oil well, shutting down the well for a period of time, and then opening the well for production after the heat energy of the steam diffuses into the oil layer. The process of steam stimulation operation can be divided into three stages: steam injection, well shutting and recovery.

[0053] For heavy oil huff and puff development, during the steam injection process, the production layer section in the oil well has permeability, so when high-pressure steam enters the oil layer, the oil layer section absorbs the steam heat by its own steam absorption capacity during the steam entering the oil layer, and the following situations will occur:

[0054] 1. The temperature of the oil layer increases, which reduces the viscosity of the crude oil. As the temperature of the oil layer increases, the viscosity of both oil and water decreases, but the viscosity of water decreases much less than that of oil, thus improving the oil-water mobility ratio.

[0055] 2. As the temperature of the oil layer rises, the oil expands, the saturation increases, and it becomes more fluid.

[0056] 3. The steam injected into the oil layer has a distillation effect, which can lower the boiling point of the reservoir liquid, but also causes oil erosion.

[0057] However, due to the large differences in the permeability of oil layers, there is uncertainty in the direction and range of steam expansion in the oil layers, so there will be a variety of development contradictions in the subsequent steam huff and puff development process. First, the contradiction between layers is prominent. The high permeability layer has a high steam absorption capacity. The steam front naturally selectively enters the high permeability layer, resulting in the low permeability layer being unable to absorb steam, forming a state where some vertical oil layers cannot be used for production; resulting in uneven plane heating and enhanced directionality of steam drive. Secondly, for the same reason, the steam cavity sweep effect is obvious in the high permeability area, and the steam cannot reach the low permeability area, and there is no heat transfer. Therefore, under the influence of the plane wave of the steam flow field, the degree of utilization of the same layer of oil reservoir will also be significantly uneven. In the later stage of steam huff and puff, due to the steam pointing along the high permeability layer and the top overlap, the steam huff and puff crude oil production effect will deteriorate, and the economic benefits will also deteriorate.

[0058] In addition, during the heavy oil thermal recovery process, the amount of crude oil produced near the wellbore increases, and a funnel cavity will gradually appear. With the gradual advancement of steam huff and puff, the funnel cavity will gradually spread to the far end, and the recovery effect will become worse and worse, and the economic limit problem will gradually appear. When it reaches the economic limit, the crude oil production decline rate will accelerate, the oil production rate will decrease, the production-injection ratio will decrease, the development effect will deteriorate, and the economic benefits will deteriorate.

[0059] When steam-driven development reaches the economic limit of the development, it is necessary to analyze and evaluate the development effect and study whether to enter the tertiary oil recovery, that is, whether to enter the steam drive stage. However, the conversion of oil reservoirs to steam drive involves the establishment of well networks, surface engineering construction, and the improvement of related projects such as oil production engineering, which is a huge project. Therefore, before the conversion, it is necessary to make an accurate judgment on the economic benefits and production evaluation to determine when is the best time to enter the steam drive stage and ensure that the steam drive stage completes the reservoir recovery rate and economic benefits indicators.

[0060] Based on this, the present invention provides a method for determining the timing of reservoir flooding based on oil saturation, such as Figure 1 As shown, the method comprises the following steps:

[0061] S110, obtaining production data of multiple target well groups during steam stimulation production;

[0062] First, multiple target well groups within the super-heavy oil block are selected. The target well groups are generally those with good well conditions, complete well networks, and continuous production. Then, the production data of multiple target well groups during steam stimulation production are obtained. Among them, the production data include: production, temperature, and perforation parameters. Perforation is mainly a process of shooting through casing and cement ring, generating channels in the rock mass, and establishing a connecting channel between the formation and the wellbore to promote the reservoir fluid to enter the wellbore. Perforation parameters include: perforation depth, perforating bullet phase, aperture, and hole density.

[0063] Generally speaking, each target well group may contain multiple production wells. When obtaining the production data of the target well group during the steam stimulation production process, it is necessary to count the production data of all production wells contained in each target well group, and then take the sum of the production data of each production well as the production data of the target well group.

[0064] S111, determining the oil saturation of each target well group according to the production data;

[0065] In one embodiment, determining the oil saturation of the target well group according to the production data includes:

[0066] Divide the production of the target well group into different production layers according to the perforation parameters;

[0067] Determine the recovery ratio of each production layer;

[0068] Determine the remaining oil saturation of each production layer based on the original oil saturation of the production layer and the recovery ratio of each production layer;

[0069] The target production layer of the target well group is determined, and the residual oil saturation of the target production layer is determined based on the residual oil saturation of each production layer; the residual oil saturation of the target production layer is the oil saturation of the target well group.

[0070] It is understandable that the reservoir contains many production layers, each with different permeability. After obtaining the production data, the production can be split into different production layers based on the perforation data, so that each production layer has a corresponding production. For each production layer, the corresponding reserves can be calculated based on the production layer area and thickness, and the recovery degree (recovery ratio) of each production layer can be determined based on the reserves.

[0071] Specifically, the degree of recovery of each production layer can be determined according to the formula: cumulative oil production / reserves*100%, where the cumulative oil production of each production layer is the output of each production layer.

[0072] Then, the remaining saturation of each production layer is determined according to the formula: remaining oil saturation = original oil saturation × (1-production degree). The original oil saturation of each production layer can be obtained in advance.

[0073] It should be noted that, due to the different connectivity of each production layer, the production layer with good connectivity will have better steam cavity expansion after steam injection, which will fully improve the oil yield. Therefore, the target production layer of each target well group is the production layer with higher connectivity, for example, the target production layer can be the production layer with connectivity greater than 70%.

[0074] S112, determining the heat storage of the oil layer when the same steam injection amount is injected into each target well group at different historical production times;

[0075] After the oil saturation of each target well group is determined, it is equivalent to determining the situation of multiple different types of oil saturation. The present invention also needs to continue to determine the changes in different oil saturations and oil layer heat storage under the condition of injecting the same amount of heat (same steam injection amount).

[0076] In one embodiment, determining the heat storage of the oil layer when the same steam injection amount is injected into each target well group at different historical production times includes:

[0077] For any historical production time, the injected oil layer heat content of each target well group is determined according to the steam injection volume, and the output heat of each target well group is determined according to the produced liquid temperature;

[0078] The heat storage of the oil layer is determined based on the heat content of the injected oil layer and the heat produced; the heat storage of the oil layer is the difference between the heat content of the injected oil layer and the heat produced.

[0079] In one embodiment, determining the injected oil layer heat content of each target well group according to the steam injection amount includes:

[0080] Determine the total injected heat based on the gas injection volume;

[0081] Determine the heat loss along the steam injection process based on the temperature change of the steam;

[0082] The heat content of the injected oil layer of the target well group is determined based on the total injected heat and the heat loss. The heat content of the injected oil layer is the difference between the total injected heat and the heat loss.

[0083] Specifically, for any target well group, the embodiment of the present invention can obtain injection data and production data for each historical production time (over the years, such as 15 years), and then obtain the gas injection volume based on the injection data, and determine the production fluid temperature based on the production data.

[0084] Then, the heat content of the injected oil layer of each target well group is calculated based on the steam injection volume, and the output heat of each target well group is calculated based on the produced liquid temperature. The difference between the heat content of the injected oil layer and the output heat is the heat storage of the oil layer.

[0085] Since steam will lose heat along the way when entering the oil layer, the heat loss along the way needs to be removed when determining the heat content of the injected oil layer based on the gas injection volume.

[0086] After the injected oil layer heat content and produced heat of each target well group over the years are determined, it is equivalent to determining the corresponding oil layer heat storage capacity under various oil saturations, and then the oil saturation and oil layer heat storage chart can be fitted. The relationship between oil saturation and oil layer heat storage can be intuitively seen from the oil saturation and oil layer heat storage chart.

[0087] For example, refer to Figure 2, assuming two target well groups A and B, the oil saturation of target well group A is 40%, and the oil saturation of target well group B is 70%. Based on the injection and production data over a 15-year period, determine the output heat and total injection heat of the two target well groups in each year from 2008 to 2022. Since the gas injection volume of the two well groups is the same, the total injection heat is the same, and the total injection heat is Figure 2 Mark 21 in.

[0088] The heat output curve of the target well group A in the 15-year period is finally determined as shown by mark 22, and the heat output curve of the target well group B in the 15-year period is shown by mark 23. The difference between mark 21 and mark 22 is the heat storage of the oil layer of the target well group A; the difference between mark 21 and mark 23 is the heat storage of the oil layer of the target well group B.

[0089] from Figure 2 It can be seen that the oil layer heat storage of target well group B with an oil saturation of 70% is significantly higher than that of target well group A with an oil saturation of 40%, indicating that when the same amount of heat is injected, the higher the oil saturation, the more heat the oil layer stores.

[0090] Furthermore, in order to further verify that the higher the oil saturation, the more heat the oil layer stores, the present invention can also analyze the temperature field development and steam cavity expansion of different oil saturations through numerical simulation under the condition of fixed injection volume and liquid production volume.

[0091] Continuing with the target well groups A and B as an example, after determining the heat content of the injected oil layer of the target well groups A and B, the target well groups A and B are simulated in combination with the heat content of the injected oil layer under the condition of fixed steam injection rate and liquid production rate, and finally the temperature field and steam cavity expansion diagram of the target well groups A and B are obtained; among which, the temperature field and steam cavity expansion diagram of the target well group A are shown in Figure 3 As shown in Figure 2, the temperature field and steam cavity expansion diagram of target well group B are shown in Figure 2. Figure 4 shown.

[0092] from Figure 3 and Figure 4 ( Figure 3 and Figure 4 The value on the right side of the figure represents the temperature value, and different colors represent different temperatures. It can be seen that one steam injection well provides steam for 9 production wells. Under the condition of fixed injection rate and liquid production rate, Figure 4 The temperature field of target well group B with an oil saturation of 70% is well developed ( Figure 4 The darker area is larger and has a higher temperature), and the expansion of the vapor cavity is more obvious; Figure 3The temperature field development and steam cavity expansion effect of target well group A with an oil saturation of 40% are second best. This also directly proves that when the same amount of heat is injected, the higher the oil saturation, the more heat the oil layer stores.

[0093] S113, determining a relationship diagram between oil saturation and oil layer heat utilization rate according to the heat storage of each oil layer;

[0094] In one embodiment, determining a relationship diagram between oil saturation and oil layer thermal utilization rate according to the amount of heat stored in each oil layer includes:

[0095] Determine the oil layer heat utilization rate of each target well group according to the oil layer heat storage;

[0096] The thermal utilization rate and oil saturation of each target well group are curve-fitted to obtain the relationship between oil saturation and thermal utilization rate of the oil layer.

[0097] Specifically, after the oil layer heat storage of each target well group is determined, the oil layer heat utilization rate of each target well group can be determined according to the oil layer heat storage. Among them, oil layer heat utilization rate = oil layer heat storage / injected oil layer heat content.

[0098] Since the target well group in this embodiment has multiple oil saturations, such as 20%, 35%, 38%, 45%, 47%, 50%, 53%, 56%, 58%, 66%, 70%, etc. Each oil saturation corresponds to an oil layer thermal utilization rate, so curve fitting can be performed on all oil saturations and corresponding oil layer thermal utilization rates to determine the relationship between oil saturation and oil layer thermal utilization rate.

[0099] The relationship between oil saturation and reservoir thermal utilization rate can be found in Figure 5 .

[0100] S114, determining the best time to switch the oil reservoir to steam flooding according to the relationship diagram between the oil saturation and the thermal utilization rate of the oil layer.

[0101] from Figure 5 It can be seen that when the oil saturation is lower than the critical value, the thermal utilization rate of the oil layer remains almost unchanged as the oil saturation increases; but when the oil saturation is greater than the critical value, the thermal utilization rate of the oil layer gradually increases.

[0102] Based on this, in one embodiment, determining the best time to switch to steam flooding in an oil reservoir according to a relationship diagram between oil saturation and oil layer thermal utilization rate includes:

[0103] Using the inflection point detection function to detect the inflection point of the relationship diagram between oil saturation and oil layer thermal utilization rate, the turning point in the relationship diagram between oil saturation and oil layer thermal utilization rate is obtained;

[0104] The oil saturation corresponding to the turning point is determined as the target oil saturation;

[0105] The best time to switch to steam flooding in the reservoir is determined according to the target oil saturation. The best time is the moment when the residual oil saturation of the reservoir is the target oil saturation.

[0106] from Figure 5 It can be seen that when the oil saturation is greater than 40%, the thermal utilization rate of the oil layer increases with the increase of oil saturation; when the oil saturation is less than 40%, the thermal utilization rate of the oil layer hardly changes with the increase of oil saturation, that is, 40% is the turning point.

[0107] Therefore, when the inflection point detection function is used to detect the inflection point of the relationship between oil saturation and oil layer thermal utilization rate, it can be determined that 40% is the turning point of oil saturation. The target oil saturation is 40%, and the best time to switch to steam drive is the moment corresponding to the residual oil saturation of the reservoir is 40%.

[0108] Then, in practical applications, the residual oil saturation of the well group can be measured. When the residual oil saturation of a well group is determined to be 40%, this is the best time to switch to steam drive.

[0109] The present invention studies the thermal utilization rates of oil layers under different oil saturations during steam stimulation of various types of oil wells, fits different oil saturations and thermal utilization rates of oil layers, and inversely deduces the critical oil saturation value required for converting the oil reservoir to steam drive based on the fitted relationship diagram. Finally, the best time to convert the oil reservoir to steam drive is accurately determined based on the residual saturation critical value, thereby ensuring the accuracy of determining the timing of conversion and improving the overall development effect of the oil field.

[0110] Based on the same inventive concept as in the above-mentioned embodiment, this embodiment also provides a device for determining the timing of reservoir flooding based on oil saturation, such as Figure 6 As shown, the device comprises:

[0111] An acquisition unit 61 is used to acquire production data of multiple target well groups during steam stimulation production;

[0112] The first determination unit 62 is used to determine the oil saturation of each target well group according to the production data; determine the oil layer heat storage when the same steam injection amount is injected into each target well group at different historical production times; and determine the relationship between the oil saturation and the oil layer heat utilization rate according to the oil layer heat storage;

[0113] The second determination unit 63 is used to determine the best time to switch to steam flooding in the oil reservoir according to the relationship diagram between the oil saturation and the thermal utilization rate of the oil layer.

[0114] In one implementation, the first determining unit 62 is specifically configured to:

[0115] Determine the oil layer heat utilization rate of each target well group according to the oil layer heat storage;

[0116] Curve fitting is performed on the oil layer thermal utilization rate and oil saturation of each target well group to obtain a relationship diagram between the oil saturation and the oil layer thermal utilization rate.

[0117] Since the device introduced in the embodiment of the present invention is a device used to implement the method for determining the timing of oil reservoir flooding based on oil saturation in the embodiment of the present invention, based on the method introduced in the embodiment of the present invention, the person skilled in the art can understand the specific structure and deformation of the device, so it is not described here. All devices used in the method of the embodiment of the present invention belong to the scope of protection of the present invention.

[0118] Based on the same inventive concept, this embodiment provides a computer device 700, such as Figure 7 As shown, it includes a memory 710, a processor 720, and a computer program 711 stored in the memory 710 and executable on the processor 720. When the processor 720 executes the computer program 711, any step of the method described above is implemented.

[0119] Based on the same inventive concept, this embodiment provides a computer-readable storage medium 800, such as Figure 7 As shown, a computer program 811 is stored thereon, and when the computer program 811 is executed by a processor, the steps of any of the methods described above are implemented.

[0120] Through one or more embodiments of the present invention, the present invention has the following beneficial effects or advantages:

[0121] The present invention provides a method, device and equipment for determining the timing of oil reservoir conversion based on oil saturation, the method comprising: obtaining production data of multiple target well groups during steam stimulation production; determining the oil saturation of each target well group according to the production data; determining the amount of heat stored in the oil layer when the same steam injection amount is injected into each target well group at different historical production times; determining a relationship diagram between oil saturation and oil layer thermal utilization rate according to the heat storage of each oil layer; determining the best timing of oil reservoir conversion to steam drive according to the relationship diagram between oil saturation and oil layer thermal utilization rate; in this way, the present invention studies the thermal utilization rate of oil layers under different oil saturations during steam stimulation of various types of oil wells, fits different oil saturations and oil layer thermal utilization rates, reversely deduce the critical value of oil saturation required for oil reservoir conversion to steam drive according to the fitted relationship diagram, and finally determine the best timing of oil reservoir conversion to steam drive according to the residual saturation critical value, thereby improving the accuracy of determining the timing of conversion to steam drive, and further improving the overall development effect of the oil field.

[0122] The algorithm and display provided herein are not inherently related to any particular computer, virtual system or other device. Various general purpose systems can also be used together with the teachings based on this. According to the above description, it is obvious that the structure required for constructing such systems. In addition, the present invention is not directed to any specific programming language either. It should be understood that various programming languages ​​can be utilized to realize the content of the present invention described herein, and the description of the above specific languages ​​is for disclosing the best mode of the present invention.

[0123] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0124] Similarly, it should be understood that in order to streamline the present disclosure and aid in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of the present invention, various features of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. However, this disclosed method should not be interpreted as reflecting the intention that the claimed invention requires more features than those explicitly recited in each claim. More specifically, as reflected in the claims below, inventive aspects lie in less than all the features of the individual embodiments disclosed above. Therefore, the claims that follow the specific embodiment are hereby expressly incorporated into the specific embodiment, with each claim itself serving as a separate embodiment of the present invention.

[0125] Those skilled in the art will appreciate that the modules in the devices in the embodiments may be adaptively changed and arranged in one or more devices different from the embodiments. The modules or units or components in the embodiments may be combined into one module or unit or component, and in addition they may be divided into a plurality of submodules or subunits or subcomponents. Except that at least some of such features and / or processes or units are mutually exclusive, all features disclosed in this specification (including the accompanying claims, abstracts and drawings) and all processes or units of any method or device disclosed in this manner may be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstracts and drawings) may be replaced by an alternative feature providing the same, equivalent or similar purpose.

[0126] In addition, those skilled in the art will appreciate that, although some embodiments herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present invention and form different embodiments. For example, in the claims below, any one of the claimed embodiments may be used in any combination.

[0127] The various component embodiments of the present invention can be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. It should be understood by those skilled in the art that a microprocessor or digital signal processor (DSP) can be used in practice to implement some or all functions of some or all components in a gateway, proxy server, or system according to an embodiment of the present invention. The present invention can also be implemented as a device or apparatus program (e.g., a computer program and a computer program product) for executing part or all of the methods described herein. Such a program implementing the present invention can be stored on a computer-readable medium, or can have the form of one or more signals. Such a signal can be downloaded from an Internet website, or provided on a carrier signal, or provided in any other form.

[0128] It should be noted that the above embodiments illustrate the present invention rather than limit it, and that those skilled in the art may devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference symbol between brackets shall not be construed as a limitation on the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "one" or "an" preceding an element does not exclude the presence of a plurality of such elements. The present invention may be implemented by means of hardware comprising a number of different elements and by means of a suitably programmed computer. In a unit claim enumerating a number of devices, several of these devices may be embodied by the same hardware item. The use of the words first, second, and third, etc., does not indicate any order. These words may be interpreted as names.

[0129] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0130] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for determining the timing of reservoir flooding based on oil saturation, characterized in that: The method comprises: Obtain production data of multiple target well groups during steam stimulation production; Determine the oil saturation of each target well group according to the production data; Determine the heat storage of the oil layer when the same steam injection amount is injected into each target well group at different historical production times; Determine a relationship diagram between oil saturation and oil layer thermal utilization rate according to the heat storage of each oil layer; The best time to switch to steam flooding in the oil reservoir is determined based on the relationship diagram between the oil saturation and the thermal utilization rate of the oil layer.

2. The method according to claim 1, characterized in that The production data includes: production, temperature and perforation parameters; determining the oil saturation of the target well group according to the production data includes: dividing the production of the target well group into different production layers according to the perforation parameters; Determine the recovery ratio of each production layer; Determine the remaining oil saturation of each production layer according to the original oil saturation of the production layer and the recovery ratio of each production layer; The target production layer of the target well group is determined, and the residual oil saturation of the target production layer is determined based on the residual oil saturation of each production layer; the residual oil saturation of the target production layer is the oil saturation of the target well group.

3. The method according to claim 1, characterized in that The determination of the heat storage in the oil layer of each target well group injected with the same steam injection amount at different historical production times comprises: For any historical production time, the injected oil layer heat content of each target well group is determined according to the steam injection volume, and the output heat of each target well group is determined according to the produced liquid temperature; The oil layer heat storage amount is determined according to the injected oil layer heat content and the produced heat; the oil layer heat storage amount is the difference between the injected oil layer heat content and the produced heat.

4. The method according to claim 3, characterized in that Determining the injected oil layer heat content of each target well group according to the steam injection amount includes: determining a total injected heat according to the gas injection amount; Determine the heat loss along the steam injection process based on the temperature change of the steam; The injected oil layer heat content of the target well group is determined according to the total injected heat and the heat loss, and the injected oil layer heat content is the difference between the total injected heat and the heat loss.

5. The method according to claim 1, characterized in that The relationship diagram between oil saturation and oil layer heat utilization rate determined according to the oil layer heat storage includes: Determine the oil layer heat utilization rate of each target well group according to the oil layer heat storage; Curve fitting is performed on the oil layer thermal utilization rate and oil saturation of each target well group to obtain a relationship diagram between the oil saturation and the oil layer thermal utilization rate.

6. The method according to claim 1, characterized in that The method of determining the best time to switch to steam flooding in an oil reservoir according to the relationship diagram between the oil saturation and the thermal utilization rate of the oil layer comprises: Performing inflection point detection on the relationship diagram between the oil saturation and the thermal utilization rate of the oil layer using an inflection point detection function to obtain a turning point in the relationship diagram between the oil saturation and the thermal utilization rate of the oil layer; determining the oil saturation corresponding to the turning point as the target oil saturation; The optimal time for switching the oil reservoir to steam flooding is determined according to the target oil saturation, and the optimal time is the time corresponding to when the remaining oil saturation of the oil reservoir is the target oil saturation.

7. A device for determining the timing of reservoir flooding based on oil saturation, characterized in that: The device comprises: An acquisition unit, used for acquiring production data of multiple target well groups during the steam stimulation production process; The first determination unit is used to determine the oil saturation of each target well group according to the production data; determine the oil layer heat storage when the same steam injection amount is injected into each target well group at different historical production times; and determine the relationship diagram between the oil saturation and the oil layer heat utilization rate according to the oil layer heat storage; The second determination unit is used to determine the best time to switch the oil reservoir to steam flooding according to the relationship diagram between the oil saturation and the thermal utilization rate of the oil layer.

8. The device according to claim 7, characterized in that The first determining unit is specifically configured to: Determine the oil layer heat utilization rate of each target well group according to the oil layer heat storage; Curve fitting is performed on the oil layer thermal utilization rate and oil saturation of each target well group to obtain a relationship diagram between the oil saturation and the oil layer thermal utilization rate.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

10. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the steps of the method according to any one of claims 1 to 6 are implemented.

Images