Method, device, medium and equipment for determining oil reservoir transfer opportunity based on heat energy

Abstract

The invention provides a method, a device, a medium and equipment for determining oil reservoir transfer opportunity based on heat energy. The method comprises the following steps: determining well bottom formation temperature of each target well group after each round of steam huff and puff according to production data of the target well group; the initial temperature of each target well group is obtained, and a mapping file needed by steam drive conversion of each target well group is created according to the well bottom formation temperature; determining the steam drive conversion opportunity of the current well group based on the mapping file; in this way, mapping files needed by steam flooding of the target well groups at different initial temperatures are established according to the well bottom formation temperatures of the target well groups with the different initial temperatures, and the mapping files can reflect the relation between the initial temperatures and the steam huff and puff turns needed by oil reservoir flooding conversion. Therefore, the steam drive conversion opportunity of the current well group can be accurately determined according to the mapping file only by knowing the initial temperature, the heat utilization rate of the current well group is improved, and the overall development effect of an oil field is ensured.

Description

Technical Field

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

[0002] Heavy oil steam injection 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 oil industry. There are two technologies used for steam injection: one is periodic steam injection and the other is steam flooding. When the crude oil production of periodic steam injection drops to the economic limit, the cycle ends and the next cycle is carried out. As the number of cycles increases, the water content increases, the oil production decreases, and the cycle becomes longer and longer.

[0003] As the amount of crude oil produced near the wellbore increases, a funnel cavity will gradually appear in the cyclic steam injection. As the steam throughput gradually advances, the funnel cavity will gradually spread to the far end, the recovery effect will become worse and worse, and the economic limit problem will gradually appear. When it reaches the vicinity of 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. When the cyclic steam injection reaches the throughput economic limit, it is necessary to study whether to enter the tertiary oil recovery, that is, the steam drive stage. However, the steam drive 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 drive, it is necessary to make an accurate judgment on the economic benefit and production evaluation to ensure that the steam drive stage completes the indicators of reservoir recovery rate and economic benefit.

[0004] 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

[0005] In response to the problems existing in the prior art, the embodiments of the present invention provide a method, device, medium and equipment for determining the timing of oil reservoir conversion based on thermal energy, 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.

[0006] In a first aspect of the present invention, a method for determining the timing of oil reservoir flooding based on thermal energy is provided, the method comprising:

[0007] Obtain production data of multiple target well groups during each round of steam stimulation production;

[0008] Determine the overall enthalpy and heat loss of each round of injection into the oil layer of each target well group according to the production data;

[0009] Determining the bottom hole formation temperature of each target well group after each round of steam stimulation according to the overall thermal enthalpy and the lost heat;

[0010] Acquire the initial temperature of each target well group, and create a mapping file required for steam flooding of each target well group according to the bottom hole formation temperature; the mapping file contains the correspondence between the initial temperature of each target well group and the steam throughput rounds required for reservoir flooding;

[0011] The timing of switching to steam flooding of the current well group is determined based on the mapping file.

[0012] In the above scheme, the overall heat enthalpy injected into the oil layer of each target well group in each round is determined according to the production data, including:

[0013] For any of the target well groups, determining a change in bottom hole formation temperature of the target well group after each round of steam stimulation;

[0014] Determine the sensible heat injected into the target well group according to the steam injection mass, steam specific heat capacity and the change in the bottom hole formation temperature during each round of steam stimulation;

[0015] Determine the latent heat injected into the target well group according to the steam injection quality and the vaporization heat of the steam during each round of steam stimulation;

[0016] The overall thermal enthalpy injected into the oil layer of each target well group in each round is determined according to the latent heat of the target well group and the sensible heat of the target well group, and the overall thermal enthalpy is the sum of the latent heat and the sensible heat.

[0017] In the above scheme, determining the bottom hole formation temperature of each target well group after each round of steam stimulation according to the overall thermal enthalpy and the lost heat includes:

[0018] determining a target heat amount based on the overall heat enthalpy and the lost heat;

[0019] The target heat is converted into a corresponding target temperature, where the target temperature is the bottom hole formation temperature after each round of steam stimulation.

[0020] In the above solution, when the mapping file is a mapping data table, the mapping file required for converting each target well group to steam flooding is created according to the bottom hole formation temperature, including:

[0021] When it is determined that the bottom hole formation temperature of each target well group reaches the temperature required for switching to steam flooding, obtaining the total number of steam stimulation rounds of the target well group;

[0022] Obtaining an initial temperature of the target well group;

[0023] The initial temperature threshold of each target well group and the total rounds of steam stimulation of the target well group are matched one by one to form the mapping file.

[0024] In the above solution, when the mapping file is a mapping data plate, the mapping file required for converting each target well group to steam flooding is created according to the bottom hole formation temperature, including:

[0025] For any target well group, obtain each bottom hole formation temperature and the corresponding steam stimulation round;

[0026] Based on the initial temperature of the target well group, curve fitting is performed on the bottom formation temperature of each well and the corresponding steam throughput rounds to obtain a steam drive demand map for the target well group; the steam drive demand map is a mapping file required for steam drive conversion for each target well group.

[0027] In the above solution, the determining of the timing of switching to steam flooding of the current well group based on the mapping file includes:

[0028] Obtaining the initial temperature of the current well group;

[0029] The mapping file is searched for the corresponding total round of steam throughput based on the initial temperature of the current well group, and the time when the current well group reaches the total round of steam throughput is determined as the timing of switching to steam drive.

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

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

[0032] A first determination unit is used to determine the overall heat enthalpy and heat loss of each round of injection into the oil layer of each target well group according to the production data;

[0033] A second determination unit is used to determine the bottom hole formation temperature of each target well group after each round of steam stimulation according to the overall thermal enthalpy and the lost heat;

[0034] A creation unit, used to obtain the initial temperature of each target well group, and create a mapping file required for steam flooding of each target well group according to the bottom hole formation temperature; the mapping file contains the correspondence between the initial temperature of each target well group and the steam throughput rounds required for reservoir flooding;

[0035] The third determining unit is used to determine the timing of switching to steam flooding of the current well group based on the mapping file.

[0036] In the above solution, the first determining unit is specifically used for:

[0037] For any of the target well groups, determining a change in bottom hole formation temperature of the target well group after each round of steam stimulation;

[0038] Determine the sensible heat injected into the target well group according to the steam injection mass, steam specific heat capacity and the change in the bottom hole formation temperature during each round of steam stimulation;

[0039] Determine the latent heat injected into the target well group according to the steam injection quality and the vaporization heat of the steam during each round of steam stimulation;

[0040] The overall thermal enthalpy injected into the oil layer of each target well group in each round is determined according to the latent heat of the target well group and the sensible heat of the target well group, and the overall thermal enthalpy is the sum of the latent heat and the sensible heat.

[0041] 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.

[0042] 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.

[0043] The present invention provides a method, device, medium and equipment for determining the timing of oil reservoir conversion based on thermal energy. The method comprises: obtaining production data of multiple target well groups during each round of steam stimulation production; determining the overall thermal enthalpy and heat loss injected into the oil layer of each target well group in each round according to the production data; determining the bottom hole formation temperature of each target well group after each round of steam stimulation according to the overall thermal enthalpy and the heat loss; obtaining the initial temperature of each target well group, and creating a mapping file required for steam conversion of each target well group according to the bottom hole formation temperature; the mapping file contains the initial temperature of each target well group and the required temperature of the oil reservoir conversion. The mapping file shows the correspondence between steam throughput cycles; based on the mapping file, the timing of converting the current well group to steam drive is determined; in this way, the present invention determines the influence of the heat energy corresponding to the steam throughput of the target well group with different initial temperatures on the bottom hole formation temperature, and establishes the mapping file required for the steam drive of each target well group at different initial temperatures according to the bottom hole formation temperature. Since the mapping file can reflect the relationship between the initial temperature and the steam throughput cycles required for the reservoir conversion, it is only necessary to know the initial temperature to accurately determine the timing of converting the current well group to steam drive according to the mapping file, thereby improving the thermal utilization rate of the current well group and ensuring the overall development effect of the oil field. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] 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.

[0045] In the attached picture:

[0046] Figure 1 A schematic flow chart of a method for determining the timing of oil reservoir flooding based on thermal energy according to an embodiment of the present invention is shown;

[0047] Figure 2 A graph showing the relationship between the cumulative steam injection amount and the bottom hole formation temperature according to one embodiment of the present invention is shown;

[0048] Figure 3 A schematic diagram showing the development of gas cavities in a target well group after five rounds of steam stimulation according to an embodiment of the present invention is shown;

[0049] Figure 4 A schematic diagram showing the development of gas cavities in a target well group after 10 rounds of steam stimulation according to an embodiment of the present invention is shown;

[0050] Figure 5 A schematic diagram showing the erosion condition of a target well group after five rounds of steam stimulation according to an embodiment of the present invention is shown;

[0051] Figure 6 A schematic diagram showing the erosion condition of a target well group after 10 rounds of steam stimulation according to an embodiment of the present invention is shown;

[0052] Figure 7 A schematic diagram of a steam conversion demand map for each target well group according to an embodiment of the present invention is shown;

[0053] Figure 8 A schematic diagram of the structure of a device for determining the timing of oil reservoir flooding based on thermal energy according to an embodiment of the present invention is shown;

[0054] Fig. 9 A schematic diagram of the structure of a computer device according to an embodiment of the present invention is shown;

[0055] Fig.10 A schematic diagram of the structure of a computer-readable storage medium according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0056] 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.

[0057] In order to better understand the technical solution of the present invention, the steam throughput technology is first introduced here.

[0058] The viscosity of crude oil is a measure of the frictional resistance of a certain part of the crude oil relative to another part when it flows, and is an important parameter for the development of oil and gas fields. For heavy oil reservoirs, heavy oil is currently classified according to the viscosity of degassed crude oil under reservoir temperature conditions, for example: ordinary heavy oil has a viscosity of 50 to 10,000 mPa·s; extra heavy oil has a viscosity of 10,000 to 50,000 mPa·s; and super heavy oil has a viscosity greater than 50,000 mPa·s. Super heavy oil has high viscosity, poor flowability, and is the most difficult to mine. The development of super heavy oil reservoirs mainly involves injecting hot fluids into the oil layer for thermal recovery, reducing the viscosity of the crude oil and improving the flowability of the crude oil.

[0059] 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.

[0060] 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:

[0061] 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.

[0062] 2. As the temperature of the oil layer rises, the oil expands, the saturation increases, and it becomes more fluid.

[0063] 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.

[0064] 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.

[0065] 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.

[0066] 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.

[0067] Based on this, the present invention provides a method for determining the timing of reservoir flooding based on thermal energy, such as Figure 1 As shown, the method comprises the following steps:

[0068] S110, obtaining production data of multiple target well groups during each round of steam stimulation production;

[0069] The present invention first selects multiple target well groups within the super-heavy oil block. The target well groups are generally well groups with good well conditions, complete well networks, and continuous production. Then, the production data of the multiple target well groups during the steam stimulation production process are obtained. The production data includes: the steam injection quality during each round of steam stimulation, the liquid production temperature after each round of steam stimulation, etc.

[0070] The initial temperatures of the target well groups may be the same or different, but all possible initial temperatures should be included. For example, the initial temperature may range from 40 to 70°C.

[0071] S111, determining the overall heat enthalpy and heat loss injected into the oil layer of each target well group in each round according to the production data;

[0072] In one embodiment, the overall heat enthalpy injected into the oil layer of each target well group in each round is determined based on production data, including:

[0073] For any target well group, determine the change in bottom hole formation temperature of the target well group after each round of steam stimulation;

[0074] The sensible heat injected into the target well group is determined based on the steam injection mass, steam specific heat capacity and bottom hole formation temperature change during each round of steam stimulation;

[0075] Determine the latent heat injected into the target well group based on the steam injection quality and the vaporization heat of the steam during each round of steam stimulation;

[0076] The overall thermal enthalpy injected into the oil layer of each target well group in each round is determined according to the latent heat and sensible heat of the target well group. The overall thermal enthalpy is the sum of the latent heat and the sensible heat.

[0077] Specifically, for any target well group, when steam huff and puff development is carried out, multiple rounds of steam need to be injected into the target well group. After steam injection, the enthalpy of the injected steam is divided into three areas, namely the liquid compression area, the saturated steam area and the superheated steam area (because the heat loss before the steam enters the formation will cause the steam to drop below the saturation pressure, and the enthalpy increment in the superheated steam area is very small, so the heat corresponding to the superheated steam area is not counted). The heat absorbed by the injected water in the liquid compression area before boiling is sensible heat; before it is completely converted into steam, it will continue to absorb heat and the temperature remains unchanged. The heat added in this process is the latent heat of vaporization.

[0078] Thus, before and after each round of steam stimulation, the bottom hole formation temperature of the target well group will have a temperature change (generally speaking, the bottom hole formation temperature after steam injection is higher than the bottom hole formation temperature before steam injection); after each round of steam stimulation, the sensible heat Q1 of the target well group can be determined according to the temperature change, as shown in formula (1):

[0079] Q1=cmΔt(1)

[0080] In formula (1), c is the specific heat capacity of steam, m is the steam injection mass during each round of steam throughput, and Δt is the temperature change.

[0081] The latent heat of the target well group can be determined according to formula (2):

[0082] Q2=mr(2)

[0083] In formula (2), m is the steam injection mass during each round of steam throughput, and r is the heat of vaporization (kcal / kg). The heat of vaporization of water at different temperatures can be obtained by looking up the table.

[0084] Then, the total enthalpy Q injected into the oil layer of each target well group in each round can be determined according to formula (3):

[0085] Q=Q1+Q2 (3)

[0086] S112, determining the bottom hole formation temperature of each target well group after each round of steam stimulation according to the overall thermal enthalpy and the lost heat;

[0087] It is understandable that during the production process, the produced fluid of the target well group will also carry out corresponding energy, and this energy will also affect the bottom hole formation temperature.

[0088] Therefore, it is also necessary to determine the bottom hole formation temperature of each target well group after each round of steam stimulation based on the overall thermal enthalpy and the lost heat, specifically including:

[0089] Determine the target heat based on the overall enthalpy and the heat loss;

[0090] The target heat is converted into the corresponding target temperature, which is the bottom hole formation temperature after each round of steam stimulation.

[0091] The corresponding heat loss can be determined according to the production temperature according to the method provided in the prior art, which will not be described in detail here. After the heat loss is determined, the difference between the total enthalpy and the heat loss can be determined as the target heat, and then the target heat is converted into the corresponding bottom hole formation temperature.

[0092] In this way, for each target well group, a corresponding bottom hole formation temperature can be determined after each round of steam stimulation.

[0093] Generally speaking, the bottom hole formation temperature will change with the continuous increase of the cumulative gas injection volume. The relationship between the cumulative gas injection volume and the bottom hole formation temperature can be shown as follows: Figure 2 shown.

[0094] from Figure 2 The functional relationship between the cumulative gas injection volume and the bottom hole formation temperature can be obtained. Figure 2 It is a scatter plot of steam injection volume and formation temperature of multiple well groups. The relationship between the cumulative gas injection volume and the bottom hole formation temperature is shown in formula (4):

[0095] y=18.936ln(x)-116.39(4)

[0096] That is, the cumulative steam injection volume changes exponentially with the bottom hole formation temperature.

[0097] The greater the cumulative gas injection volume, the better the steam cavity development of the target well group; the greater the cumulative gas injection volume, the more obvious the denudation effect of the target well group. Figure 3 and Figure 4 , Figure 3 The gas cavity development after 5 rounds of steam stimulation in a target well group is shown in Figure 1. Figure 4 This is the development of the gas cavity in a target well group after 10 rounds of steam stimulation. It can be clearly seen that Figure 4 The air cavities in the stratum are better developed (more dark areas, indicating higher temperatures).

[0098] refer to Figure 5 and Figure 6 , Figure 5 The erosion situation after 5 rounds of steam stimulation in a target well group is shown in Figure 1. Figure 6 This is the erosion situation after 10 rounds of steam stimulation in a target well group. It can be clearly seen that Figure 5 There is only a little light-colored area on the top (indicating that the crude oil has been driven away), and there is still a large black area below (this area still contains a lot of crude oil that has not been driven away by steam; Figure 6 There is a large light-colored area in the upper middle (indicating that the crude oil has been driven away), and there is a small black area in the lower middle (this area still contains a large amount of crude oil that has not been driven away by steam); therefore, it can be seen Figure 6 The erosion effect is better. Figure 6 S o Represents oil saturation. It can be seen that Figure 6 The oil saturation of the black area at the bottom is greater than that of the light area at the top, which also proves that Figure 6 Most of the crude oil in the upper area has been driven out.

[0099] That is, when the bottom hole formation temperature does not reach the starting temperature, the crude oil fluidity is poor, the displacement resistance is large, the steam cavity is poorly developed, and the erosion effect is not obvious.

[0100] Furthermore, for target well groups with different initial temperatures, steam huff-and-puff development was carried out at different initial temperatures, and the amount of steam injected in each round was the same, which was 4000 cubic meters. Table 1 can be obtained.

[0101] Table 1

[0102]

[0103]

[0104] As can be seen from Table 1, when the starting temperature of the target well group is 40°C, 8 rounds of steam huff and puff are required to reach the preheating temperature; when the starting temperature of the target well group is 50°C, 7 rounds of steam huff and puff are required to reach the preheating temperature; when the starting temperature of the target well group is 60°C, 5 rounds of steam huff and puff are required to reach the preheating temperature; when the starting temperature of the target well group is 70°C, 3.5 rounds of steam huff and puff are required to reach the preheating temperature. The preheating temperature can be understood as the bottom hole formation temperature of the target well group that can reach the steam drive temperature, which is determined based on experience, for example, 75-80°C.

[0105] S113, obtaining the initial temperature of each target well group, and creating a mapping file required for steam flooding of each target well group according to the bottom hole formation temperature; the mapping file contains the correspondence between the initial temperature of each target well group and the steam throughput rounds required for reservoir flooding;

[0106] It can be seen from the above that if the initial temperature of the target well group is different, the number of steam throughput required to reach the temperature that can be converted to steam drive is also different. However, according to Table 1, there is a certain relationship between the initial temperature and the number of steam throughput required for the final conversion to steam drive. Therefore, the present invention can create a mapping file required for the conversion of each target well group to steam drive according to the bottom hole formation temperature. The mapping file contains the corresponding relationship between the initial temperature of each target well group and the number of steam throughput required for the conversion of the reservoir.

[0107] The mapping file may be a mapping data table or a mapping data plate. In one embodiment, when the mapping file is a mapping data table, the mapping file required for steam flooding of each target well group is created according to the bottom hole formation temperature, including:

[0108] When it is determined that the bottom hole formation temperature of each target well group reaches the temperature required for steam flooding, the total number of steam injections and injections of the target well group is obtained;

[0109] Obtain the initial temperature of the target well group;

[0110] The initial temperature threshold of each target well group is matched one by one with the total rounds of steam stimulation and puffing of the target well group to form a mapping file.

[0111] Continuing with the above example, when the starting temperature of the target well group is 40℃, 8 rounds of steam injection are required to reach the preheating temperature; when the starting temperature of the target well group is 50℃, 7 rounds of steam injection are required to reach the preheating temperature; when the starting temperature of the target well group is 60℃, 5 rounds of steam injection are required to reach the preheating temperature; when the starting temperature of the target well group is 70℃, 3.5 rounds of steam injection are required to reach the preheating temperature. Therefore, in the mapping data table, 40℃ and 8 times can be stored in correspondence, 50℃ and 7 times can be stored in correspondence, 60℃ and 5 times can be stored in correspondence, and 70℃ and 3.5 times can be stored in correspondence. The final mapping file contains the initial temperature of each target well group and the steam injection rounds required for reservoir conversion.

[0112] When the mapping file is a mapping data plate, the mapping file required for steam flooding of each target well group is created according to the bottom hole formation temperature, including:

[0113] For any target well group, obtain the bottom formation temperature of each well and the corresponding steam stimulation rounds;

[0114] Based on the initial temperature of the target well group, curve fitting is performed on the bottom formation temperature of each well and the corresponding steam throughput rounds to obtain the steam drive demand map of the target well group; the steam drive demand map is the mapping file required for the steam drive of each target well group.

[0115] Specifically, for a target well group with any initial temperature, a corresponding bottom hole formation temperature will be determined each time a steam injection is performed. Then, as shown in Table 1, the bottom hole formation temperature corresponding to each steam injection can be stored until the stored bottom hole formation temperature reaches the temperature required for the target well group to switch to steam injection.

[0116] In this way, for each target well group, the bottom hole formation temperature corresponding to each layer of steam throughput and the corresponding steam throughput cycles can be fitted to obtain the steam drive demand curve of the target well group. The steam drive demand curves of all target well groups form a total steam drive demand map. The steam drive demand map represents the steam throughput cycles of the target well group and the corresponding bottom hole formation temperature. Therefore, the steam drive demand map is also the mapping file required for steam drive of each target well group.

[0117] Continuing with the above example, see Figure 7 , Figure 7 This is the steam demand chart for each target well group. Figure 7In the figure, the steam drive demand curve corresponding to the starting temperature of the target well group is 40°C as shown by mark 71, the steam drive demand curve corresponding to the starting temperature of the target well group is 50°C as shown by mark 72, the steam drive demand curve corresponding to the starting temperature of the target well group is 60°C as shown by mark 73, and the steam drive demand curve corresponding to the starting temperature of the target well group is 70°C as shown by mark 74.

[0118] S114, determining the timing of switching to steam flooding for the current well group based on the mapping file.

[0119] Since the mapping file contains the correspondence between the initial temperature of each target well group and the steam injection rounds required for the reservoir injection, in one embodiment, determining the steam injection timing of the current well group based on the mapping file includes:

[0120] Get the initial temperature of the current well group;

[0121] Based on the initial temperature of the current well group, the corresponding total round of steam throughput is searched in the mapping file, and the time when the current well group reaches the corresponding total round of steam throughput is determined as the timing of switching to steam drive.

[0122] For example, assuming that the initial temperature of the current well group (the well group to be converted to steam flooding) is 40°C, it can be determined from the mapping file that the current well group needs to perform 8 steam huffs and puffs before it can enter steam flooding development, that is, the timing of steam flooding for the current well group is the time corresponding to the 8th steam huff and puff. If the current well group has only performed 4 steam huffs and puffs at this time, it will take another 4 steam huffs and puffs before it can be converted to steam flooding.

[0123] The present invention determines the influence of the heat energy corresponding to the steam throughput of the target well groups with different initial temperatures on the bottom hole formation temperature, and establishes the mapping files required for the steam drive of each target well group at different initial temperatures according to the bottom hole formation temperature. Since the mapping file can reflect the relationship between the initial temperature and the steam throughput rounds required for the oil reservoir drive, it is only necessary to know the initial temperature to accurately determine the timing of the steam drive of the current well group according to the mapping file, thereby improving the thermal utilization rate of the current well group and ensuring the overall development effect of the oil field.

[0124] 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 thermal energy, such as Figure 8 As shown, the device comprises:

[0125] An acquisition unit 81 is used to acquire production data of multiple target well groups during each round of steam stimulation production;

[0126] A first determination unit 82 is used to determine the overall heat enthalpy and heat loss injected into the oil layer of each target well group in each round according to the production data;

[0127] A second determination unit 83 is used to determine the bottom hole formation temperature of each target well group after each round of steam stimulation according to the overall thermal enthalpy and the lost heat;

[0128] The creation unit 84 is used to obtain the initial temperature of each target well group, and create a mapping file required for steam flooding of each target well group according to the bottom hole formation temperature; the mapping file contains the corresponding relationship between the initial temperature of each target well group and the steam injection rounds required for reservoir flooding;

[0129] The third determining unit 85 is used to determine the timing of switching to steam flooding of the current well group based on the mapping file.

[0130] In one implementation, the first determining unit 82 is specifically configured to:

[0131] For any of the target well groups, determining a change in bottom hole formation temperature of the target well group after each round of steam stimulation;

[0132] Determine the sensible heat injected into the target well group according to the steam injection mass, steam specific heat capacity and the change in the bottom hole formation temperature during each round of steam stimulation;

[0133] Determine the latent heat injected into the target well group according to the steam injection quality and the vaporization heat of the steam during each round of steam stimulation;

[0134] The overall thermal enthalpy injected into the oil layer of each target well group in each round is determined according to the latent heat of the target well group and the sensible heat of the target well group, and the overall thermal enthalpy is the sum of the latent heat and the sensible heat.

[0135] 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 diversion based on thermal energy 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.

[0136] Based on the same inventive concept, this embodiment provides a computer device 900, such as Fig. 9 As shown, it includes a memory 910, a processor 920, and a computer program 911 stored in the memory 910 and executable on the processor 920. When the processor 920 executes the computer program 911, any step of the method described above is implemented.

[0137] Based on the same inventive concept, this embodiment provides a computer-readable storage medium 1000, such as Fig.10 As shown, a computer program 1011 is stored thereon, and when the computer program 1011 is executed by a processor, the steps of any of the methods described above are implemented.

[0138] Through one or more embodiments of the present invention, the present invention has the following beneficial effects or advantages:

[0139] The present invention provides a method, device, medium and equipment for determining the timing of oil reservoir conversion based on thermal energy. The method comprises: obtaining production data of multiple target well groups during each round of steam stimulation production; determining the overall thermal enthalpy and heat loss injected into the oil layer of each target well group in each round according to the production data; determining the bottom hole formation temperature of each target well group after each round of steam stimulation according to the overall thermal enthalpy and the heat loss; obtaining the initial temperature of each target well group, and creating a mapping file required for steam conversion of each target well group according to the bottom hole formation temperature; the mapping file contains the initial temperature of each target well group and the required temperature of the oil reservoir conversion. The mapping file shows the correspondence between steam throughput cycles; based on the mapping file, the timing of converting the current well group to steam drive is determined; in this way, the present invention determines the influence of the heat energy corresponding to the steam throughput of the target well group with different initial temperatures on the bottom hole formation temperature, and establishes the mapping file required for the steam drive of each target well group at different initial temperatures according to the bottom hole formation temperature. Since the mapping file can reflect the relationship between the initial temperature and the steam throughput cycles required for the reservoir conversion, it is only necessary to know the initial temperature to accurately determine the timing of converting the current well group to steam drive according to the mapping file, thereby improving the thermal utilization rate of the current well group and ensuring the overall development effect of the oil field.

[0140] 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.

[0141] 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.

[0142] 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.

[0143] 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.

[0144] 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.

[0145] 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.

[0146] 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.

[0147] Although the preferred embodiments of the present application 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 falling within the scope of the present application.

[0148] 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 thermal energy, characterized in that: The method comprises: Obtain production data of multiple target well groups during each round of steam stimulation production; Determine the overall enthalpy and heat loss of each round of injection into the oil layer of each target well group according to the production data; Determining the bottom hole formation temperature of each target well group after each round of steam stimulation according to the overall thermal enthalpy and the lost heat; Acquire the initial temperature of each target well group, and create a mapping file required for steam flooding of each target well group according to the bottom hole formation temperature; the mapping file contains the correspondence between the initial temperature of each target well group and the steam throughput rounds required for reservoir flooding; The timing of switching to steam flooding of the current well group is determined based on the mapping file.

2. The method according to claim 1, characterized in that Determining the overall heat enthalpy injected into the oil layer of each target well group in each round according to the production data includes: For any of the target well groups, determining a change in bottom hole formation temperature of the target well group after each round of steam stimulation; Determine the sensible heat injected into the target well group according to the steam injection mass, steam specific heat capacity and the change in the bottom hole formation temperature during each round of steam stimulation; Determine the latent heat injected into the target well group according to the steam injection quality and the vaporization heat of the steam during each round of steam stimulation; The overall thermal enthalpy injected into the oil layer of each target well group in each round is determined according to the latent heat of the target well group and the sensible heat of the target well group, and the overall thermal enthalpy is the sum of the latent heat and the sensible heat.

3. The method according to claim 1, characterized in that Determining the bottom hole formation temperature of each target well group after each round of steam stimulation according to the overall thermal enthalpy and the lost heat includes: determining a target heat amount based on the overall heat enthalpy and the lost heat; The target heat is converted into a corresponding target temperature, where the target temperature is the bottom hole formation temperature after each round of steam stimulation.

4. The method according to claim 1, characterized in that When the mapping file is a mapping data table, the mapping file required for converting each target well group to steam flooding is created according to the bottom hole formation temperature, including: When it is determined that the bottom hole formation temperature of each target well group reaches the temperature required for switching to steam flooding, obtaining the total number of steam stimulation rounds of the target well group; Obtaining an initial temperature of the target well group; The initial temperature threshold of each target well group and the total rounds of steam stimulation of the target well group are matched one by one to form the mapping file.

5. The method according to claim 1, characterized in that When the mapping file is a mapping data plate, the mapping file required for converting each target well group to steam flooding is created according to the bottom hole formation temperature, including: For any target well group, obtaining each bottom hole formation temperature and corresponding steam stimulation rounds; Based on the initial temperature of the target well group, curve fitting is performed on the bottom formation temperature of each well and the corresponding steam throughput rounds to obtain a steam drive demand map for the target well group; the steam drive demand map is a mapping file required for steam drive conversion for each target well group.

6. The method according to claim 1, characterized in that The determining the steam drive transition timing of the current well group based on the mapping file includes: Obtaining the initial temperature of the current well group; The mapping file is searched for the corresponding total round of steam throughput based on the initial temperature of the current well group, and the time when the current well group reaches the total round of steam throughput is determined as the timing of switching to steam drive.

7. A device for determining the timing of oil reservoir flooding based on thermal energy, characterized in that: The device comprises: An acquisition unit, used for acquiring production data of multiple target well groups during each round of steam stimulation production; A first determination unit is used to determine the overall heat enthalpy and heat loss of each round of injection into the oil layer of each target well group according to the production data; A second determination unit is used to determine the bottom hole formation temperature of each target well group after each round of steam stimulation according to the overall thermal enthalpy and the lost heat; A creation unit, used to obtain the initial temperature of each target well group, and create a mapping file required for steam flooding of each target well group according to the bottom hole formation temperature; the mapping file contains the correspondence between the initial temperature of each target well group and the steam throughput rounds required for reservoir flooding; The third determining unit is used to determine the timing of switching to steam flooding of the current well group based on the mapping file.

8. The device according to claim 7, characterized in that The first determining unit is specifically configured to: For any of the target well groups, determining a change in bottom hole formation temperature of the target well group after each round of steam stimulation; Determine the sensible heat injected into the target well group according to the steam injection mass, steam specific heat capacity and the change in the bottom hole formation temperature during each round of steam stimulation; Determine the latent heat injected into the target well group according to the steam injection quality and the vaporization heat of the steam during each round of steam stimulation; The overall thermal enthalpy injected into the oil layer of each target well group in each round is determined according to the latent heat of the target well group and the sensible heat of the target well group, and the overall thermal enthalpy is the sum of the latent heat and the sensible heat.

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.

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