Method and device for determining residual heat of oil layer

Abstract

This specification provides a method and device for determining residual heat in oil layers. Based on this method, before specific implementation, a preset sensitivity analysis is performed based on a preset multiple rounds of steam huff and puff development simulation of a reference well to determine the parameter types of target reservoir static parameters, target fluid physical property parameters, and target operating parameters that are more sensitive to the prediction of residual heat in oil layers after multiple rounds of steam huff and puff development; then the target reservoir static parameters, target fluid physical property parameters, and target operating parameters of the reference well are used to establish a formation residual heat prediction model. During specific implementation, the target reservoir static parameters, target fluid physical property parameters, and target operating parameters related to the target area can be obtained; then, the target reservoir static parameters, target fluid physical property parameters, and target operating parameters are processed by using the formation residual heat prediction model to accurately and efficiently determine the residual heat in oil layers after multiple rounds of steam huff and puff development in the target area, and guide the development of heavy oil.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas development, and in particular to a method and device for determining residual heat of an oil layer. Background Art

[0002] In oil and gas development, for heavy oil reservoirs, it is usually necessary to first perform multiple rounds of steam stimulation (a thermal oil recovery method) on the oil layer before oil can be successfully extracted. However, based on existing methods, it is often difficult to accurately and efficiently determine the residual heat of the oil layer after multiple rounds of steam stimulation.

[0003] To address the above problems, no effective solution has been proposed yet. Summary of the invention

[0004] The present specification provides a method and device for determining oil layer residual heat, which can accurately and efficiently predict the oil layer residual heat after multiple rounds of steam stimulation development in the target area with a low data processing volume, and thus can better guide the heavy oil development in the target area.

[0005] The embodiment of this specification provides a method for determining residual heat of an oil layer, comprising:

[0006] Obtaining target reservoir static parameters, target fluid physical property parameters and target operating parameters related to the target area; wherein the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters and the parameter types of the target operating parameters are determined in advance by a preset sensitivity analysis performed after multiple rounds of steam stimulation development simulation based on a reference well;

[0007] The target reservoir static parameters, target fluid physical property parameters and target operating parameters are processed by using the formation residual heat prediction model to obtain a target prediction result; wherein the formation residual heat prediction model is established in advance by using the target reservoir static parameters, target fluid physical property parameters and target operating parameters of a reference well;

[0008] Based on the target prediction results, the residual heat of the oil layer after multiple rounds of steam stimulation and puffing development in the target area is determined.

[0009] In one embodiment, the parameter types of the target reservoir static parameters include: porosity, reservoir height; the parameter types of the target fluid physical parameters include: permeability; the parameter types of the target operating parameters include: steam dryness, injection temperature, cumulative injection volume.

[0010] In one embodiment, the formation residual heat prediction model is used to process the target reservoir static parameters, target fluid physical property parameters and target operation parameters to obtain target prediction results, including:

[0011] According to the following formula, the formation residual heat prediction model is used to process the target reservoir static parameters, target fluid physical property parameters and target operation parameters:

[0012]

[0013] Among them, Er is the prediction result of the residual heat of the oil layer after multiple rounds of steam stimulation development in the target area, k o is the permeability, H is the reservoir height, φ is the porosity, x is the steam quality, T inj is the injection temperature, Q ac is the cumulative injection volume.

[0014] In one embodiment, the method further comprises:

[0015] The parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters and the parameter types of the target operating parameters are determined by performing a preset sensitivity analysis based on a preset multiple rounds of steam stimulation development simulation of a reference well in the following manner:

[0016] Acquiring a first reservoir static parameter, a first fluid physical property parameter, and a first operating parameter of a reference well;

[0017] According to the first reservoir static parameter, the first fluid physical property parameter and the first operation parameter of the reference well, a preset multiple rounds of steam huff and puff development simulation is performed to obtain the temperature distribution of the reference well after the multiple rounds of steam huff and puff development simulation;

[0018] According to the temperature distribution after multiple rounds of steam huff and puff development simulation of the reference well, the residual heat of the oil layer after multiple rounds of steam huff and puff development simulation of the reference well is calculated;

[0019] According to the residual heat of the oil layer after multiple rounds of steam huff-and-puff development simulation of the reference well, by performing a preset sensitivity analysis, the parameter types of the first reservoir static parameters, the parameter types of the first fluid physical property parameters and the parameter types of the first operating parameters are respectively screened out.

[0020] In one embodiment, according to the temperature distribution of the reference well after multiple rounds of steam stimulation and puff development simulation, the residual heat of the oil layer after multiple rounds of steam stimulation and puff development simulation of the reference well is calculated, including:

[0021] According to the following formula, the residual heat of the oil layer after multiple rounds of steam stimulation and puffing development simulation of the reference well is calculated:

[0022]

[0023] Among them, Er′ is the residual heat of the oil layer after multiple rounds of steam stimulation and development simulation of the reference well, r is the distance between the position point in the oil layer of the reference well and the center of the reference well, h is the thickness of the oil layer, T r The temperature after multiple cycles of steam stimulation and puffing at the location in the reservoir of the reference well, T i is the initial temperature of the reference well in the oil layer, φ is the porosity, C o is the specific heat capacity of crude oil, S o is the saturation of crude oil, ρ o is the density of crude oil, C w is the specific heat capacity of water, S w is the water saturation, ρ w is the density of water, C r is the specific heat capacity of rock, ρ r is the density of the rock.

[0024] In one embodiment, according to the residual heat of the oil layer after multiple rounds of steam huff-and-puff development simulation of the reference well, by performing a preset sensitivity analysis, the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters, and the parameter types of the target operating parameters are respectively screened out from the parameter types of the first reservoir static parameters, the parameter types of the first fluid physical property parameters, and the parameter types of the first operating parameters, including:

[0025] According to the residual heat of the oil layer after multiple rounds of steam huff-and-puff development simulation of the reference well, an orthogonal test is performed on the parameters of the first reservoir static parameter, the first fluid physical property parameter and the first operation parameter of the reference well to obtain the corresponding test results;

[0026] According to the test results, by performing range analysis and variance analysis, the parameter types of the first reservoir static parameters, the parameter types of the first fluid physical property parameters and the parameter types of the first operating parameters are screened out to select the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters and the parameter types of the target operating parameters that meet the requirements.

[0027] In one embodiment, the method further comprises:

[0028] The formation residual heat prediction model is established using the target reservoir static parameters, target fluid physical property parameters and target operation parameters of the reference well in the following manner:

[0029] Obtain target reservoir static parameters, target fluid physical property parameters and target operation parameters of the reference well;

[0030] Using the target reservoir static parameters, target fluid physical property parameters and target operating parameters of the reference well, as well as the oil layer residual heat after multiple rounds of steam stimulation development simulation of the reference well, a multivariate linear regression is performed to construct a formation residual heat prediction model.

[0031] In one embodiment, after determining the residual heat of the oil reservoir after multiple rounds of steam stimulation and puffing development in the target area, the method further includes:

[0032] According to the residual heat of the oil layer after multiple rounds of steam huff and puff development in the target area, determine the development strategy that matches the later stage of multiple rounds of steam huff and puff development in the target area;

[0033] Based on the development strategy that matches the late stage of multiple rounds of steam stimulation development in the target area, heavy oil development is carried out in the target area.

[0034] The embodiment of this specification also provides a device for determining oil layer residual heat, including:

[0035] An acquisition module, used for acquiring target reservoir static parameters, target fluid physical property parameters and target operation parameters related to the target area; wherein the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters and the parameter types of the target operation parameters are determined in advance by performing a preset sensitivity analysis after a preset multiple rounds of steam stimulation development simulation based on a reference well;

[0036] A processing module, used for processing the target reservoir static parameters, target fluid physical property parameters and target operating parameters by using the formation residual heat prediction model to obtain a target prediction result; wherein the formation residual heat prediction model is established in advance by using the target reservoir static parameters, target fluid physical property parameters and target operating parameters of a reference well;

[0037] The determination module is used to determine the residual heat of the oil layer after multiple rounds of steam stimulation development in the target area according to the target prediction results.

[0038] The embodiments of the present specification also provide a computer-readable storage medium having computer instructions stored thereon, and the instructions, when executed by a processor, implement the following steps: obtaining target reservoir static parameters, target fluid physical property parameters and target operating parameters related to the target area; wherein the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters and the parameter types of the target operating parameters are pre-determined by a preset sensitivity analysis performed after a preset multiple rounds of steam stimulation development simulation based on a reference well; processing the target reservoir static parameters, the target fluid physical property parameters and the target operating parameters using a formation residual heat prediction model to obtain a target prediction result; wherein the formation residual heat prediction model is pre-established using the target reservoir static parameters, the target fluid physical property parameters and the target operating parameters of a reference well; and determining the residual heat of the oil layer after multiple rounds of steam stimulation development in the target area based on the target prediction result.

[0039] Based on the method and device for determining oil layer residual heat provided in this specification, before specific implementation, the parameter types of target reservoir static parameters, target fluid physical property parameters and target operating parameters that are more sensitive to the prediction of oil layer residual heat after multiple rounds of steam huff and puff development can be determined through a preset sensitivity analysis based on a preset multiple rounds of steam huff and puff development simulation of a reference well; then, by using the target reservoir static parameters, target fluid physical property parameters and target operating parameters of the reference well, a formation residual heat prediction model that is only related to the target reservoir static parameters, target fluid physical property parameters and target operating parameters is established. During specific implementation, the target reservoir static parameters, target fluid physical property parameters and target operating parameters related to the target area can be collected and obtained in a targeted manner; then, by using the above-mentioned formation residual heat prediction model to process the target reservoir static parameters, target fluid physical property parameters and target operating parameters, the corresponding target prediction results are obtained; then, based on the target prediction results, the oil layer residual heat after multiple rounds of steam huff and puff development in the target area is determined. This makes it possible to accurately and efficiently predict in advance the residual heat of the oil layer after multiple rounds of steam stimulation development in the target area with a lower amount of data processing, so as to more effectively guide the heavy oil development in the target area. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of this specification, the drawings required for use in the embodiments will be briefly introduced below. The drawings described below are only some embodiments recorded in this specification. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0041] Figure 1 is a flow chart of a method for determining oil layer waste heat provided by an embodiment of this specification;

[0042] Figure 2 is a schematic diagram of the structure of an electronic device provided by an embodiment of this specification;

[0043] Figure 3 It is a schematic diagram of the structure of a device for determining residual heat of an oil layer provided in one embodiment of the present specification;

[0044] Figure 4 is a schematic diagram of an embodiment of a method for determining oil layer waste heat provided by an embodiment of this specification, in a scenario example;

[0045] Figure 5 is a schematic diagram of an embodiment of a method for determining oil layer waste heat provided by an embodiment of this specification, in a scenario example;

[0046] Figure 6is a schematic diagram of an embodiment of a method for determining oil layer waste heat provided by an embodiment of this specification, in a scenario example;

[0047] Figure 7 is a schematic diagram of an embodiment of a method for determining oil layer waste heat provided by an embodiment of this specification, in a scenario example;

[0048] Figure 8 is a schematic diagram of an embodiment of a method for determining oil layer waste heat provided by an embodiment of this specification, in a scenario example;

[0049] Fig. 9 is a schematic diagram of an embodiment of a method for determining oil layer waste heat provided by an embodiment of this specification, in a scenario example;

[0050] Fig.10 is a schematic diagram of an embodiment of a method for determining oil layer waste heat provided by an embodiment of this specification, in a scenario example;

[0051] Fig.11 is a schematic diagram of an embodiment of a method for determining oil layer waste heat provided by an embodiment of this specification, in a scenario example;

[0052] Fig.12 It is a schematic diagram of an embodiment of a method for determining oil layer waste heat provided by an embodiment of this specification, in a scenario example. DETAILED DESCRIPTION

[0053] In order to enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below in conjunction with the drawings in the embodiments of this specification. Obviously, the described embodiments are only part of the embodiments of this specification, not all of the embodiments. Based on the embodiments in this specification, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this specification.

[0054] Considering that based on the existing methods, after multiple rounds of thermal recovery treatments such as steam stimulation on the oil layer, it is often impossible to accurately assess the residual heat of the oil layer, which in turn affects the subsequent exploitation of the oil layer.

[0055] In view of the above problems, the present specification considers that before specific implementation, a reference well may be selected from the target area to be subjected to steam stimulation, and a preset multiple-round steam stimulation development simulation may be performed based on the reference well to obtain the temperature distribution of the reference well after the multiple-round steam stimulation development simulation; then, based on the temperature distribution of the reference well after the multiple-round steam stimulation development simulation, an integral operation may be performed to obtain the residual heat of the oil layer after the multiple-round steam stimulation development simulation of the reference well; then, based on the residual heat of the oil layer after the multiple-round steam stimulation development simulation of the reference well, a preset sensitivity analysis may be performed to screen out the parameter types of the first reservoir static parameters, the parameter types of the first fluid physical property parameters, and the parameter types of the first operating parameters, respectively; further, the target reservoir static parameters, the target fluid physical property parameters, and the target operating parameters of the reference well, as well as the residual heat of the oil layer after the multiple-round steam stimulation development simulation of the reference well, may be used to construct a formation residual heat prediction model by performing multiple linear regression. In specific implementation, the relevant target reservoir static parameters, target fluid physical parameters and target operating parameters of the target area can be obtained first; and the target reservoir static parameters, target fluid physical parameters and target operating parameters can be processed by using the formation residual heat prediction model previously constructed based on the reference well to determine the residual heat of the oil layer after multiple rounds of steam stimulation and puffing development in the target area. In this way, the residual heat of the oil layer after multiple rounds of steam stimulation and puffing development in the target area can be accurately and efficiently predicted in advance with a lower amount of data processing.

[0056] See also Figure 1 As shown, the embodiment of this specification provides a method for determining residual heat of an oil layer. In specific implementation, the method may include the following contents.

[0057] S101: Obtain target reservoir static parameters, target fluid physical property parameters and target operating parameters related to the target area; wherein the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters and the parameter types of the target operating parameters are determined in advance by a preset sensitivity analysis performed after a preset multiple rounds of steam stimulation development simulation based on a reference well.

[0058] S102: Using a formation residual heat prediction model to process the target reservoir static parameters, target fluid physical property parameters and target operating parameters to obtain a target prediction result; wherein the formation residual heat prediction model is established in advance using the target reservoir static parameters, target fluid physical property parameters and target operating parameters of a reference well.

[0059] S103: According to the target prediction result, the residual heat of the oil layer after multiple rounds of steam stimulation development in the target area is determined.

[0060] In some embodiments, the target area may be specifically understood as an area to be developed that contains a heavy oil reservoir.

[0061] The above-mentioned heavy oil (also called high-viscosity heavy crude oil) may specifically refer to crude oil with a density greater than 0.92 g / cm 3 , crude oil with viscosity higher than 50mPa·s.

[0062] For heavy oil reservoirs, it is often difficult to effectively exploit them using conventional oil extraction methods. Usually, thermal oil extraction methods are used to first increase the temperature of the heavy oil reservoir to reduce the viscosity of the crude oil, thereby changing the fluidity of the heavy oil in the oil layer so that it can be successfully extracted.

[0063] When thermal oil production is carried out, the oil layer will be subjected to multiple rounds of steam stimulation. The steam stimulation may include: injecting a certain amount of steam into the heavy oil production well, then shutting the well for 3-5 days, and then opening the well for production after the heat diffuses to the deep part of the reservoir, until the production capacity is reduced to the cycle conversion condition. According to the above method, by carrying out multiple rounds of steam stimulation, the above-mentioned steam injection, well shutting and production process are cyclically carried out until the cyclic oil production of steam stimulation reaches the economic limit.

[0064] When mining heavy oil, the residual heat in the oil layer is often large in the later stages of multiple rounds of steam huff-and-puff development. This residual heat in the oil layer will affect the subsequent development characteristics and the selection of successor methods. However, based on existing methods, it is often difficult to accurately and quantitatively evaluate the residual heat in the oil layer, which leads to the inability to effectively use the residual heat in the oil layer to guide the specific heavy oil development.

[0065] In some embodiments, the target reservoir static parameters, target fluid physical property parameters and target operating parameters can specifically be the target reservoir static parameters, fluid physical property parameters and target operating parameters that are pre-screened based on reference wells and are more sensitive to the prediction of residual heat of the oil layer after multiple rounds of steam stimulation development, and are usually easier to collect.

[0066] The reference well may specifically be a known well in the target area, or a known well in an area with the same or similar formation conditions as the target area.

[0067] Among them, the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters, and the parameter types of the target operating parameters are specifically determined in advance through a preset sensitivity analysis performed after a preset multiple rounds of steam stimulation development simulation based on a reference well. The method for determining the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters, and the parameter types of the target operating parameters will be described separately later.

[0068] In some embodiments, the parameter types of the target reservoir static parameters may specifically include: porosity, reservoir height, etc.; the target fluid physical parameters may specifically include: permeability, etc.; the target operating parameters may specifically include: steam dryness, injection temperature, cumulative injection volume, etc.

[0069] In some embodiments, the above-mentioned formation residual heat prediction model can be specifically understood as a fitting model that is only related to the target reservoir static parameters, target fluid physical parameters and target operating parameters, and can more accurately determine the residual heat of the oil layer after multiple rounds of steam stimulation and development. Among them, the above-mentioned formation residual heat prediction model is specifically established in advance using the target reservoir static parameters, target fluid physical parameters and target operating parameters of the reference well. The method for establishing the formation residual heat prediction model will be explained separately later.

[0070] In some embodiments, the above-mentioned formation residual heat prediction model is used to process the target reservoir static parameters, target fluid physical property parameters and target operation parameters to obtain the target prediction results. When implemented specifically, the following contents may be included:

[0071] According to the following formula, the formation residual heat prediction model is used to process the target reservoir static parameters, target fluid physical property parameters and target operation parameters:

[0072]

[0073] Among them, Er is the prediction result of the residual heat of the oil layer after multiple rounds of steam stimulation development in the target area, k o is the permeability, H is the reservoir height, φ is the porosity, x is the steam quality, T inj is the injection temperature, Q ac is the cumulative injection volume.

[0074] In some embodiments, when the method is specifically implemented, it may also include determining the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters, and the parameter types of the target operating parameters by performing a preset sensitivity analysis based on a preset multiple rounds of steam stimulation development simulation of a reference well in the following manner:

[0075] S1: collecting the first reservoir static parameter, the first fluid physical property parameter and the first operation parameter of the reference well;

[0076] S2: performing a preset multiple rounds of steam huff and puff development simulation according to the first reservoir static parameter, the first fluid physical property parameter and the first operation parameter of the reference well, and obtaining the temperature distribution of the reference well after the multiple rounds of steam huff and puff development simulation;

[0077] S3: Calculate the residual heat of the oil layer after multiple rounds of steam huff and puff development simulation of the reference well according to the temperature distribution after multiple rounds of steam huff and puff development simulation of the reference well;

[0078] S4: Based on the residual heat of the oil layer after multiple rounds of steam huff-and-puff development simulation of the reference well, by performing a preset sensitivity analysis, the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters and the parameter types of the target operating parameters are respectively screened out from the parameter types of the first reservoir static parameters, the parameter types of the first fluid physical property parameters and the parameter types of the first operating parameters.

[0079] In some embodiments, the first reservoir static parameter may specifically include one or more of the following: reservoir permeability, porosity, oil layer thickness, initial pressure, initial temperature, net-to-gross ratio, compressibility, initial oil-water interface, reservoir height, etc. The first fluid physical property parameter may specifically include one or more of the following: oil-gas relative permeability, thermal conductivity, crude oil viscosity, etc. The first operating parameter may specifically include one or more of the following: steam injection rate, steam dryness, injection temperature, cumulative injection volume, etc.

[0080] Of course, it should be noted that the first reservoir static parameter, the first fluid physical property parameter and the first operating parameter listed above are only schematic illustrations. In specific implementation, other suitable parameters may be introduced as the first reservoir static parameter, the first fluid physical property parameter and the first operating parameter according to specific conditions and processing requirements.

[0081] In some embodiments, during specific implementation, based on historical heavy oil production records and the difficulty of obtaining parameters, parameters that have an impact on oil layer residual heat and are relatively easy to collect can be initially screened out as the above-mentioned first reservoir static parameters, first fluid physical property parameters and first operating parameters.

[0082] In some embodiments, after collecting the first reservoir static parameter, the first fluid physical property parameter and the first operating parameter of the reference well, the method may further include the following when implemented: averaging the first reservoir static parameter, the first fluid physical property parameter and the first operating parameter collected at different positions and depths to obtain the first reservoir static parameter, the first fluid physical property parameter and the first operating parameter after the averaging process. Subsequently, the first reservoir static parameter, the first fluid physical property parameter and the first operating parameter after the averaging process may be used to replace the first reservoir static parameter, the first fluid physical property parameter and the first operating parameter to perform the preset multi-round steam huff and puff development simulation, which may simplify the calculation process, reduce the amount of data processing and the data processing time, and on the other hand, because the first reservoir static parameter, the first fluid physical property parameter and the first operating parameter after the averaging process used are more representative than the first reservoir static parameter, the first fluid physical property parameter and the first operating parameter before the averaging process, the temperature distribution of the reference well after the multi-round steam huff and puff development simulation obtained by the preset multi-round steam huff and puff development simulation may have a higher accuracy.

[0083] In some embodiments, the preset multiple rounds of steam huff and puff development simulation are performed according to the first reservoir static parameter, the first fluid physical property parameter and the first operation parameter of the reference well. When implemented specifically, the following contents may be included:

[0084] S1: constructing a single-well steam huff-and-puff numerical simulation model of the reference well according to a first reservoir static parameter, a first fluid physical property parameter and a first operation parameter of the reference well;

[0085] S2: Based on the single-well steam throughput numerical simulation model of the reference well, multiple rounds of steam throughput development simulation are performed according to the preset simulation rules.

[0086] In some embodiments, the preset number of rounds may be 9. In specific implementation, other values ​​may be set as the preset number of rounds according to the specific conditions of the target area. For example, the preset number of rounds may also be set to 7 or 8.

[0087] In some embodiments, the preset simulation rules may specifically include: a simulation cycle of each round of steam throughput development simulation with a specified duration, wherein the specified duration may specifically be greater than or equal to 3 months and less than or equal to 4 months.

[0088] Through the above embodiments, multiple rounds of steam huff and puff development simulation can be performed on the reference well more accurately, and the temperature distribution after multiple rounds of steam huff and puff development simulation of the reference well with relatively high accuracy and relatively small error can be obtained.

[0089] In some embodiments, the temperature distribution after multiple rounds of steam stimulation and puff development simulation of the reference well may specifically include the temperatures after multiple rounds of steam stimulation and puff development simulation at multiple locations in the oil layer of the reference well.

[0090] In some embodiments, during specific implementation, the residual heat of the oil layer after multiple rounds of steam huff and puff development simulation of the reference well can be calculated through integral operation based on the temperature of the reference well after multiple rounds of steam huff and puff development simulation, combined with the initial temperature of the location point in the oil layer of the reference well.

[0091] In some embodiments, the above calculation of the residual heat of the oil layer after multiple rounds of steam huff and puff development simulation of the reference well according to the temperature distribution after multiple rounds of steam huff and puff development simulation of the reference well may include the following contents during specific implementation:

[0092] According to the following formula, the residual heat of the oil layer after multiple rounds of steam stimulation and puffing development simulation of the reference well is calculated:

[0093]

[0094] Among them, Er′ is the residual heat of the oil layer after multiple rounds of steam stimulation and development simulation of the reference well, r is the distance between the position point in the oil layer of the reference well and the center of the reference well, h is the thickness of the oil layer, T r The temperature after multiple cycles of steam stimulation and puffing at the location in the reservoir of the reference well, T i is the initial temperature of the reference well in the oil layer, φ is the porosity, C o is the specific heat capacity of crude oil, S o is the saturation of crude oil, ρ o is the density of crude oil, C w is the specific heat capacity of water, S w is the water saturation, ρ w is the density of water, C r is the specific heat capacity of rock, ρ r is the density of the rock.

[0095] In some embodiments, the above-mentioned residual heat of the oil layer after multiple rounds of steam stimulation and puffing development simulation of the reference well is subjected to a preset sensitivity analysis, and the parameter types of the target oil reservoir static parameters, the parameter types of the target fluid physical property parameters and the parameter types of the target operating parameters are respectively screened out from the parameter types of the first oil reservoir static parameters, the parameter types of the first fluid physical property parameters and the parameter types of the first operating parameters. When implemented specifically, the following contents may be included:

[0096] S1: According to the residual heat of the oil layer after multiple rounds of steam huff-and-puff development simulation of the reference well, an orthogonal test is performed on the parameters of the first reservoir static parameter, the first fluid physical property parameter and the first operating parameter of the reference well to obtain the corresponding test results;

[0097] S2: Based on the test results, by performing range analysis and variance analysis, the parameter types of the first reservoir static parameters, the parameter types of the first fluid physical property parameters and the parameter types of the first operating parameters are screened out to select the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters and the parameter types of the target operating parameters that meet the requirements.

[0098] In some embodiments, considering that there are a large number of first reservoir static parameters, first fluid physical property parameters and first operating parameters, an orthogonal experiment method can be used to reduce the amount of data calculation and efficiently screen out parameter types of target reservoir static parameters, target fluid physical property parameters and target operating parameters that meet the requirements (for example, those that are more sensitive to the prediction of residual heat in the oil layer after multiple rounds of steam stimulation development).

[0099] Among them, the above-mentioned orthogonal experiment (also known as orthogonal experimental design) is a test method for studying multiple factors and multiple levels. By conducting the above-mentioned orthogonal experiment, some representative points can be selected from the comprehensive test for testing based on orthogonality. These representative points have the following characteristics: "evenly dispersed, neat and comparable".

[0100] In some embodiments, specifically according to the residual heat of the oil layer after multiple rounds of steam stimulation development simulation of the reference well, by conducting orthogonal experiments on the parameters of the first reservoir static parameter, the first fluid physical property parameter and the first operating parameter of the reference well, multiple factors can be configured, wherein one factor corresponds one-to-one to one of the first reservoir static parameter, the first fluid physical property parameter and the first operating parameter; the same number of levels are configured for each factor (for example, 3 different values ​​are configured for each parameter); a matching orthogonal table is selected, multiple experiments are conducted to obtain multiple residual heat calculation results, and the multiple residual heat calculation results are counted in the orthogonal table to obtain corresponding test results.

[0101] Specifically, for example, the first reservoir static parameter, the first fluid property parameter and the first operation parameter include 13 different types of parameters, and there are 13 corresponding factors; 3 different values ​​are configured for each factor, and accordingly, each factor has 3 levels; select L 27 (13 3 ) and conducted 27 tests; and statistically analyzed the residual heat calculation results in the orthogonal table to obtain the corresponding test results.

[0102] In some embodiments, when performing range analysis and variance analysis based on the test results, the influence of different parameters on formation residual heat can be preliminarily analyzed by performing range analysis based on the test results; and then a multi-factor variance analysis method is used to perform a sensitivity analysis on the above parameters to further determine the influence of different parameters on formation residual heat.

[0103] Among them, the above-mentioned multi-factor variance analysis is specifically used to study whether two or more control variables have a significant impact on the observed variables. Based on the multi-factor variance analysis, it can not only analyze the independent impact of multiple factors on the observed variables, but also analyze whether the interaction of multiple control factors can have a significant impact on the distribution of the observed variables.

[0104] Specifically, for example, based on the results obtained from the above-mentioned differential analysis and variance analysis, it can be determined that after multiple rounds of steam throughput, the parameters arranged in descending order of sensitivity to the residual heat of the oil layer after multiple rounds of steam throughput are: reservoir height (also called reservoir thickness), cycle injection volume (or cumulative injection volume), permeability, porosity, steam dryness, injection temperature, thermal conductivity, initial viscosity of crude oil, crude oil density...

[0105] Among them, the sensitivity of parameters such as thermal conductivity, initial crude oil viscosity, and crude oil density is relatively small compared to the top-ranked parameters and can be ignored.

[0106] Therefore, a preset number of parameters (for example, 6) ranked at the top can be screened out as parameter types of target reservoir static parameters, parameter types of target fluid physical parameters, and parameter types of target operating parameters that meet the requirements (for example, porosity, reservoir height, permeability, cumulative injection volume, steam dryness, injection temperature).

[0107] In some embodiments, when the above method is implemented, the target reservoir static parameters, target fluid physical property parameters and target operation parameters of the reference well may be used to establish a formation residual heat prediction model in the following manner:

[0108] S1: Obtain target reservoir static parameters, target fluid physical property parameters and target operation parameters of the reference well;

[0109] S2: Using the target reservoir static parameters, target fluid physical property parameters and target operating parameters of the reference well, as well as the oil layer residual heat after multiple rounds of steam stimulation development simulation of the reference well, a multivariate linear regression is performed to construct a formation residual heat prediction model.

[0110] Through the above embodiments, a formation residual heat prediction model that is only related to the target reservoir static parameters, target fluid physical parameters and target operating parameters can be fitted, does not need to calculate and rely on the temperature distribution after multiple rounds of steam stimulation development simulation, and does not need to perform integral operations, but still has a high degree of accuracy.

[0111] In some embodiments, when performing multivariate linear regression, the Gauss-Newton method can be used to perform multivariate nonlinear regression on the oil layer waste heat after multiple rounds of steam stimulation development simulation of the reference well, so as to obtain the data fitting relationship between the oil layer waste heat (or reservoir waste heat) Er′ and various parameters (including: target reservoir static parameters, target fluid physical property parameters and target operation parameters of the reference well).

[0112] Specifically, the Gauss-Newton method can be understood as an algorithm for solving nonlinear least squares. Based on this algorithm, a polynomial function can be used to approximate a given function value, and then an estimated value of the minimum point is obtained. The above operation is repeated until the accuracy meets the requirements.

[0113] In some embodiments, after determining the residual heat of the oil layer after multiple rounds of steam stimulation and puffing development in the target area, the method may further include the following when implemented:

[0114] S1: According to the residual heat of the oil layer after multiple rounds of steam huff and puff development in the target area, determine the development strategy that matches the later stage of multiple rounds of steam huff and puff development in the target area;

[0115] S2: Develop heavy oil in the target area based on the development strategy that matches the late stage of multiple rounds of steam stimulation development in the target area.

[0116] In some embodiments, before specific implementation, the historical heavy oil production records can be combined to analyze the oil layer production characteristics under different formation waste heat conditions, and multiple preset development strategies corresponding to multiple preset formation waste heat ranges can be configured. Accordingly, during specific implementation, the preset formation waste heat range to which the oil layer waste heat after multiple rounds of steam huff and puff development in the target area belongs can be first determined; then the preset development strategy corresponding to the formation waste heat range can be determined as a development strategy that matches the later stage of multiple rounds of steam huff and puff development in the target area; and then the development strategy can be used as a reference to more effectively guide the heavy oil development in the target area, thereby obtaining better production results.

[0117] As can be seen from the above, based on the method for determining the residual heat of the oil layer provided in the embodiment of this specification, before specific implementation, the preset sensitivity analysis can be performed after the preset multiple rounds of steam huff and puff development simulation based on the reference well to determine the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters, and the parameter types of the target operating parameters that are more sensitive to the prediction of the residual heat of the oil layer after multiple rounds of steam huff and puff development; and then, by using the target reservoir static parameters, the target fluid physical property parameters, and the target operating parameters of the reference well, a formation residual heat prediction model that is only related to the target reservoir static parameters, the target fluid physical property parameters, and the target operating parameters is established. During specific implementation, the target reservoir static parameters, the target fluid physical property parameters, and the target operating parameters related to the target area can be obtained in a targeted manner; and then, by using the above-mentioned formation residual heat prediction model to process the target reservoir static parameters, the target fluid physical property parameters, and the target operating parameters, the corresponding target prediction results are obtained; and according to the target prediction results, the residual heat of the oil layer after multiple rounds of steam huff and puff development in the target area is determined. This makes it possible to accurately and efficiently predict in advance the residual heat of the oil layer after multiple rounds of steam stimulation development in the target area with a lower amount of data processing, so as to more effectively guide the heavy oil development in the target area.

[0118] The embodiment of the present specification also provides an electronic device, including a processor and a memory for storing instructions executable by the processor, wherein the processor can perform the following steps according to the instructions when implemented: obtaining target reservoir static parameters, target fluid physical property parameters and target operating parameters related to the target area; wherein the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters and the parameter types of the target operating parameters are pre-determined by a preset sensitivity analysis performed after a preset multiple rounds of steam stimulation development simulation based on a reference well; processing the target reservoir static parameters, the target fluid physical property parameters and the target operating parameters using a formation residual heat prediction model to obtain a target prediction result; wherein the formation residual heat prediction model is pre-established using the target reservoir static parameters, the target fluid physical property parameters and the target operating parameters of the reference well; and determining the residual heat of the oil layer after multiple rounds of steam stimulation development in the target area according to the target prediction result.

[0119] In order to complete the above instructions more accurately, refer to Figure 2 As shown, the embodiment of this specification also provides another specific electronic device, wherein the electronic device includes a network communication port 201, a processor 202 and a memory 203, and the above structures are connected through internal cables so that each structure can perform specific data interaction.

[0120] Among them, the network communication port 201 can be specifically used to obtain target reservoir static parameters, target fluid physical property parameters and target operating parameters related to the target area; wherein the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters and the parameter types of the target operating parameters are determined in advance by a preset sensitivity analysis performed after a preset multiple rounds of steam stimulation development simulation based on a reference well.

[0121] The processor 202 can be specifically used to use the formation residual heat prediction model to process the target reservoir static parameters, target fluid physical property parameters and target operating parameters to obtain a target prediction result; wherein the formation residual heat prediction model is established in advance using the target reservoir static parameters, target fluid physical property parameters and target operating parameters of a reference well; based on the target prediction result, the residual heat of the oil layer after multiple rounds of steam stimulation development in the target area is determined.

[0122] The memory 203 may be specifically used to store corresponding instruction programs.

[0123] In this embodiment, the network communication port 201 can be a virtual port that is bound to different communication protocols so that different data can be sent or received. For example, the network communication port can be a port responsible for web data communication, a port responsible for FTP data communication, or a port responsible for email data communication. In addition, the network communication port can also be a physical communication interface or communication chip. For example, it can be a wireless mobile network communication chip, such as GSM, CDMA, etc.; it can also be a Wifi chip; it can also be a Bluetooth chip.

[0124] In this embodiment, the processor 202 may be implemented in any appropriate manner. For example, the processor may take the form of a microprocessor or processor and a computer-readable medium storing a computer-readable program code (such as software or firmware) executable by the (micro)processor, a logic gate, a switch, an application specific integrated circuit (ASIC), a programmable logic controller, and an embedded microcontroller, etc. This specification does not limit this.

[0125] In this embodiment, the memory 203 may include multiple levels. In a digital system, anything that can store binary data can be a memory; in an integrated circuit, a circuit with a storage function but no physical form is also called a memory, such as RAM, FIFO, etc.; in a system, a storage device with a physical form is also called a memory, such as a memory stick, TF card, etc.

[0126] The embodiment of the present specification also provides a computer storage medium based on the above-mentioned method for determining oil layer residual heat, and the computer storage medium stores computer program instructions, which, when executed, realize: obtaining target reservoir static parameters, target fluid physical property parameters and target operating parameters related to the target area; wherein the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters and the parameter types of the target operating parameters are pre-determined by a preset sensitivity analysis performed after a preset multiple rounds of steam stimulation development simulation based on a reference well; processing the target reservoir static parameters, the target fluid physical property parameters and the target operating parameters using a formation residual heat prediction model to obtain a target prediction result; wherein the formation residual heat prediction model is pre-established using the target reservoir static parameters, the target fluid physical property parameters and the target operating parameters of the reference well; and determining the oil layer residual heat after multiple rounds of steam stimulation development in the target area according to the target prediction result.

[0127] In this embodiment, the storage medium includes, but is not limited to, a random access memory (RAM), a read-only memory (ROM), a cache, a hard disk (HDD), or a memory card. The memory may be used to store computer program instructions. The network communication unit may be an interface for network connection communication set in accordance with the standard specified by the communication protocol.

[0128] In this embodiment, the functions and effects specifically implemented by the program instructions stored in the computer storage medium can be explained in comparison with other implementations and will not be described in detail here.

[0129] See also Figure 3 As shown, at the software level, the embodiment of this specification also provides a device for determining oil layer residual heat, which may specifically include the following structural modules:

[0130] The acquisition module 301 may be specifically used to acquire the target reservoir static parameters, target fluid physical property parameters and target operation parameters related to the target area; wherein the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters and the parameter types of the target operation parameters are determined in advance by performing a preset sensitivity analysis based on a preset multiple rounds of steam stimulation development simulation based on a reference well;

[0131] The processing module 302 may be specifically used to process the target reservoir static parameters, target fluid physical property parameters and target operating parameters using the formation residual heat prediction model to obtain a target prediction result; wherein the formation residual heat prediction model is established in advance using the target reservoir static parameters, target fluid physical property parameters and target operating parameters of a reference well;

[0132] The determination module 303 may be specifically used to determine the residual heat of the oil layer after multiple rounds of steam stimulation development in the target area according to the target prediction result.

[0133] In some embodiments, the parameter types of the target reservoir static parameters include: porosity, reservoir height; the parameter types of the target fluid physical parameters include: permeability; the parameter types of the target operating parameters include: steam dryness, injection temperature, cumulative injection volume.

[0134] In some embodiments, when the processing module 302 is implemented, the target reservoir static parameters, target fluid physical property parameters and target operation parameters can be processed using the formation residual heat prediction model according to the following formula:

[0135]

[0136] Among them, Er is the prediction result of the residual heat of the oil layer after multiple rounds of steam stimulation development in the target area, k o is the permeability, H is the reservoir height, φ is the porosity, x is the steam quality, T inj is the injection temperature, Q ac is the cumulative injection volume.

[0137] In some embodiments, when the device is specifically implemented, the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters, and the parameter types of the target operating parameters can be determined in the following manner by performing a preset sensitivity analysis after a preset multiple-round steam huff and puff development simulation based on a reference well: collecting the first reservoir static parameters, the first fluid physical property parameters, and the first operating parameters of the reference well; performing a preset multiple-round steam huff and puff development simulation based on the first reservoir static parameters, the first fluid physical property parameters, and the first operating parameters of the reference well to obtain the temperature distribution of the reference well after the multiple-round steam huff and puff development simulation; calculating the residual heat of the oil layer after the multiple-round steam huff and puff development simulation of the reference well based on the temperature distribution of the reference well after the multiple-round steam huff and puff development simulation; and screening out the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters, and the parameter types of the target operating parameters from the parameter types of the first reservoir static parameters, the parameter types of the first fluid physical property parameters, and the parameter types of the first operating parameters, respectively, based on the residual heat of the oil layer after the multiple-round steam huff and puff development simulation of the reference well, by performing a preset sensitivity analysis.

[0138] In some embodiments, when the device is implemented, the residual heat of the oil layer after multiple rounds of steam stimulation and puffing development simulation of the reference well can be calculated according to the following formula:

[0139]

[0140] Among them, Er′ is the residual heat of the oil layer after multiple rounds of steam stimulation and development simulation of the reference well, r is the distance between the position point in the oil layer of the reference well and the center of the reference well, h is the thickness of the oil layer, T r The temperature after multiple cycles of steam stimulation and puffing at the location in the reservoir of the reference well, T i is the initial temperature of the reference well in the oil layer, φ is the porosity, C o is the specific heat capacity of crude oil, S o is the saturation of crude oil, ρ o is the density of crude oil, C w is the specific heat capacity of water, S w is the water saturation, ρ w is the density of water, C r is the specific heat capacity of rock, ρ r is the density of the rock.

[0141] In some embodiments, when the device is specifically implemented, the parameter types of target reservoir static parameters, target fluid physical property parameters and target operating parameters can be respectively screened out from the parameter types of the first reservoir static parameters, the parameter types of the first fluid physical property parameters and the parameter types of the first operating parameters by performing a preset sensitivity analysis according to the residual heat of the oil layer after multiple rounds of steam huff and puff development simulation of the reference well in the following manner: according to the residual heat of the oil layer after multiple rounds of steam huff and puff development simulation of the reference well, an orthogonal test is performed on the parameters of the first reservoir static parameters, the first fluid physical property parameters and the first operating parameters of the reference well to obtain corresponding test results; according to the test results, range analysis and variance analysis are performed to screen out the parameter types of the first reservoir static parameters, the parameter types of the first fluid physical property parameters and the parameter types of the first operating parameters to meet the requirements.

[0142] In some embodiments, when the device is implemented, it can also be used to establish a formation residual heat prediction model using the target reservoir static parameters, target fluid physical property parameters and target operating parameters of a reference well in the following manner: obtaining the target reservoir static parameters, target fluid physical property parameters and target operating parameters of the reference well; using the target reservoir static parameters, target fluid physical property parameters and target operating parameters of the reference well, as well as the residual heat of the oil layer after multiple rounds of steam stimulation development simulation of the reference well, to perform multivariate linear regression to construct a formation residual heat prediction model.

[0143] In some embodiments, after determining the residual heat of the oil layer after multiple rounds of steam huff and puff development in the target area, the device, when implemented, can also be used to determine a development strategy that matches the later stage of multiple rounds of steam huff and puff development in the target area based on the residual heat of the oil layer after multiple rounds of steam huff and puff development in the target area; and perform heavy oil development in the target area based on the development strategy that matches the later stage of multiple rounds of steam huff and puff development in the target area.

[0144] It should be noted that the units, devices or modules described in the above embodiments can be implemented by computer chips or entities, or by products with certain functions. For the convenience of description, the above devices are described separately by functions divided into various modules. Of course, when implementing this specification, the functions of each module can be implemented in the same or more software and / or hardware, or the modules that implement the same function can be implemented by a combination of multiple sub-modules or sub-units. The device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0145] It can be seen from the above that the device for determining oil layer waste heat provided in the embodiments of this specification can accurately and efficiently predict the oil layer waste heat after multiple rounds of steam stimulation development in the target area in advance with a lower amount of data processing, so as to more effectively guide the heavy oil development in the target area.

[0146] In a specific scenario example, the method for determining the residual heat of an oil layer provided in the embodiment of this specification can be applied to evaluate the residual heat of an oil layer after steam stimulation development of a heavy oil reservoir in a target block. Figure 4 As shown, the following steps may be included.

[0147] The first step is to obtain average reservoir static parameters, fluid physical property parameters and operation parameters of the target block (for example, target reservoir static parameters, target fluid physical property parameters and target operation parameters after averaging).

[0148] Specifically, the reservoir static parameters, fluid physical property parameters and operating parameters (for example, target reservoir static parameters, target fluid physical property parameters and target operating parameters) obtained at different depths, different locations and different sublayers of the target block reservoir can be averaged to provide data support for subsequent numerical simulations.

[0149] In this step, the same parameters at different locations and depths can be averaged to perform averaging. This is because the model established and used later is different from the conventional mine model. In order to facilitate calculation and reduce time cost, a single well model is used. Therefore, the physical parameters obtained after averaging the target block are more representative and can better simulate and characterize the reservoir temperature distribution in the later stage of multiple rounds of steam stimulation.

[0150] The parameters used may specifically include: reservoir static parameters (e.g., reservoir permeability, porosity, oil layer thickness, initial pressure, initial temperature, net-to-gross ratio, compressibility, initial oil-water interface, etc.), fluid physical parameters (e.g., oil-gas relative permeability, thermal conductivity, crude oil viscosity, etc.), and operating parameters (e.g., steam injection rate, steam dryness, etc.). The net-to-gross ratio may specifically refer to the ratio of net sandstone (effective thickness) to gross sandstone (sandstone thickness).

[0151] It should be noted that, in the specific implementation, the number of specific parameters is not limited and can be flexibly adjusted according to the actual reservoir characteristics, but generally should include the above-mentioned reservoir static parameters, fluid physical parameters and operating parameters.

[0152] The second step is to conduct numerical simulation of single-well steam stimulation and reservoir operation (for example, conduct multiple rounds of steam stimulation and development simulation on a reference well).

[0153] Specifically, reservoir numerical simulation software can be used to average the reservoir static parameters, fluid physical parameters and operating parameters of the target block obtained in the first step to establish a reservoir numerical simulation model for multiple rounds of steam stimulation in a single well, so as to simulate the temperature distribution of the oil layer after multiple rounds of steam stimulation. Among them, the above-mentioned single-well numerical simulation can reflect the production characteristics as a whole based on the average parameters of the target block, and the formation parameters are consistent, so the simulation speed is fast. In addition, the grid required for the single-well numerical simulation here is much smaller than that of the mine model, which can fully reflect the residual heat distribution characteristics.

[0154] In this step, due to the different oil layer thicknesses, cycle heat injection amounts, steam injection pressures, oil layer temperatures, production rates, water content and other factors in the production process, the heat loss in the heating zone and the heat carried by the produced liquid are also different. Therefore, for this numerical simulation model, a total of 13 parameters are set, including reservoir thickness, porosity, horizontal permeability, net-to-gross ratio, compression coefficient, crude oil density, initial crude oil viscosity, thermal conductivity, cycle steam injection volume, steam dryness, injection temperature, and gas injection pressure. The reservoir permeability is set to 5000mD, 3000mD, and 1000mD, and the steam dryness is set to 0.5, 0.7, and 0.9. The values ​​of other parameters can be found in Table 1.

[0155] Table 1 Table of parameter values ​​for single well multi-round throughput

[0156]

[0157] In this step, a numerical simulation model of multi-round steam stimulation in a single well can be established, and numerical simulation of the reservoir can be performed for 3-4 months per round to simulate the temperature distribution characteristics at the end of the 7th to 9th rounds and obtain the corresponding numerical simulation results.

[0158] Through the above numerical simulation results, the relationship between temperature T (for example, the temperature distribution after multiple rounds of steam stimulation development simulation of the reference well) and the distance r from the well point can be obtained. After simulating multiple stimulations, the remaining total heat in the reservoir can be expressed as:

[0159]

[0160] The above formula is the heat after the huff and puff that is higher than the original reservoir. The initial temperature of the oil layer needs to be excluded to obtain the following formula:

[0161]

[0162] Where, Er′ is waste heat, J; r is the distance from a certain point in the oil layer to the center of the well, m; h is the thickness of the oil layer, m; T r —Temperature at a certain point in the oil layer, °C; T i —initial temperature of oil layer, °C; φ—porosity; C o —Specific heat capacity of crude oil, J / (kg·℃); C w —Specific heat capacity of water, J / (kg·℃); C r —Specific heat capacity of rock, J / (kg·℃); S o —Crude oil saturation; S w —water saturation; ρ o —Crude oil density, kg / m 3 ρ w —Density of water, kg / m 3 ρ r —Density of rock, kg / m 3 .

[0163] Specifically, the reservoir temperature distribution of the single-well multi-cycle steam stimulation model can be obtained and derived through numerical simulation. For details, please refer to Fig.11 and Fig.12 The gray value in the figure represents the temperature. Based on the above formula, the reservoir residual heat (or formation residual heat) is calculated by numerical integration. It can be seen that: with the increase of throughput rounds, the formation temperature gradually rises, among which the temperature close to the well point is the highest, and the temperature far from the well point is the lowest.

[0164] Specifically, taking the reservoir temperature distribution at the end of the 9th round under different permeabilities and gas injection pressures as an example, the reservoir residual heat at the end of multiple rounds is calculated. The reservoir temperature distribution under different permeabilities at the end of the 9th round can be found in Figure 5 , Figure 6 and Figure 7 As shown. Among them, Figure 5 Shown is the temperature distribution at a permeability of 5000 mD. Figure 6 Shown is the temperature distribution at a permeability of 3000 mD. Figure 7 The temperature distribution is shown when the permeability is 1000 mD. The gray value in the figure represents the temperature.

[0165] comprehensive Figure 5 , Figure 6 and Figure 7 It can be seen that the greater the permeability, the greater the temperature near the wellbore after multiple rounds of steam huff and puff, and the larger the heating area. In addition, the temperature gradually decreases with the increase of distance. In addition, it can be seen that in the later stage of multiple rounds of huff and puff, the temperature distribution shows that when the distance from the production well is the same, the temperature of the upper part of the formation is higher than the temperature of the lower part, which indicates that the steam overburden phenomenon at the far wellbore is serious in the later stage of multiple rounds of huff and puff. After obtaining the temperature distribution of multiple rounds of huff and puff, the residual heat of the formation can be calculated by formula integration.

[0166] In this step, the residual heat of the oil layer after multiple rounds of huff and puff can be obtained according to the above formula of residual heat of the oil layer and the simulation results of the numerical model. And according to the calculated residual heat of the oil layer, the residual heat curve relationship diagram of the oil layer at different positions under different permeabilities can be drawn. For details, please refer to Figure 8 As shown in the figure, the residual heat distribution diagram of the later stage of multiple rounds of huff-and-puff under different permeabilities is shown. It can be seen that: from the figure, the thermal enthalpy value of the residual heat of the oil layer near the wellbore is the highest, and as the distance r from the wellbore increases, the residual heat of the oil layer far from the wellbore gradually decreases. In addition, the results in the figure show that the difference in permeability has a serious impact on the residual heat distribution.

[0167] You can also select different steam dryness to perform the same operation and draw the relationship diagram of oil layer residual heat curve at different positions under different steam dryness. Fig. 9 As shown in the figure, the residual heat distribution diagram of multiple rounds of throughput at different steam dryness is shown. It can be seen that with the increase of steam dryness, the residual heat of the oil layer generally increases. The higher the steam dryness, the higher the thermal enthalpy value, so the residual heat is positively correlated with the dryness.

[0168] Through the analysis of the residual heat, it can be seen that: with the increase of permeability, the temperature of the oil layer near the wellbore decreases, but with the increase of the distance r from the well point, the temperature far away from the well point increases; the thermal enthalpy value of the residual heat of the oil layer near the wellbore is the highest, and with the increase of the distance r from the well point, the residual heat of the oil layer far from the well point gradually decreases.

[0169] In addition, with the increase of steam dryness and periodic injection volume, the temperature of any point in the oil layer rises. That is, steam dryness and periodic injection volume are also positively correlated with the residual heat of the oil layer.

[0170] The third step is to conduct residual heat sensitivity analysis of the oil layer.

[0171] In this step, since there are many parameters that affect the residual heat, 13 parameters (for example, the first reservoir static parameters, the first fluid physical property parameters and the first operating parameters) can be selected first, and then the key parameters that have the most significant impact on the residual heat need to be screened out from the 13 parameters as the key parameters (for example, target reservoir static parameters, target fluid physical property parameters and target operating parameters) for establishing a late-stage throughput residual heat correlation formula (for example, a formation residual heat prediction model).

[0172] In specific implementation, orthogonal experiments can be selected to conduct sensitivity analysis on key parameters. Among them, orthogonal experimental design is another design method for studying multiple factors and multiple levels. It selects some representative points from comprehensive experiments based on orthogonality for testing. These representative points have "even dispersion, neatness and comparability". The above-mentioned orthogonal experimental design is a method of fractional factorial design, which is an efficient, fast and economical experimental design method. Based on this method, the number of simulation operations can be greatly reduced and the parameters that most significantly affect waste heat can be obtained through analysis.

[0173] Specifically, there are 13 parameters, i.e. 13 factors. Each factor has 3 levels. Therefore, we can choose L 27 (13 3 ) and conduct 27 experiments. The residual heat calculation results are counted in the orthogonal table.

[0174] Then, the residual heat calculation results in the orthogonal table are summarized. Specifically, a differential analysis is first performed to preliminarily analyze the impact of different parameters on residual heat. Then, a multi-factor variance analysis is used to perform a sensitivity analysis on these parameters.

[0175] Among them, multi-factor variance analysis is used to study whether two or more control variables have a significant impact on the observed variables. Multi-factor variance analysis can not only analyze the independent impact of multiple factors on the observed variables, but also analyze whether the interaction of multiple control factors can have a significant impact on the distribution of the observed variables.

[0176] According to the results of differential analysis and variance analysis, it can be shown that after multiple rounds of huff and puff, the sensitive parameters for the temperature of the oil layer and the residual heat of the oil layer after huff and puff are in the following order of sensitivity: reservoir thickness, periodic injection volume, permeability, porosity, steam dryness, injection temperature, thermal conductivity, initial viscosity of crude oil, and crude oil density. Among them, the influence of thermal conductivity, initial viscosity of crude oil, crude oil density, and injection pressure is negligible compared to the previous parameters. After simulating huff and puff, for the temperature of the oil layer and the residual heat of the oil layer after huff and puff, the parameters in the following order of sensitivity are: reservoir thickness, periodic injection volume, permeability, porosity, steam dryness, injection temperature, thermal conductivity, initial viscosity of crude oil, and crude oil density.

[0177] The fourth step is to establish a residual heat evaluation model (eg, a formation residual heat prediction model) and apply the model.

[0178] After screening the important parameters that affect the reservoir residual heat, the results can be summarized, and the Gauss-Newton method can be used to perform multivariate nonlinear regression on multiple rounds of reservoir residual heat to obtain the relationship between the oil layer residual heat Er and each parameter (i.e., the formation residual heat prediction model). Among them, the above-mentioned Gauss-Newton method can be specifically an algorithm for solving nonlinear least squares. The basic idea of ​​the algorithm is to use a polynomial function to approximate a given function value, and then find the estimated value of the minimum point, and repeat the operation until a certain accuracy is achieved.

[0179] After calculation, the following relationship can be obtained as the regression result:

[0180]

[0181] Where, x is steam quality, T inj —Injection temperature, Q ac —Cumulative injection volume, φ—porosity, H—reservoir height, k o —Permeability.

[0182] From the above relationship, it can be seen that each parameter has not only a linear relationship with the residual heat, but also the square of the reservoir thickness is related to the residual heat. The effects of steam dryness and gas injection temperature on the residual heat also interact. In addition, the steam dryness is inversely proportional to the residual heat.

[0183] Further, we can get the comparison analysis diagram of the calculation error and the numerical simulation results based on this relationship, see Fig.10 As shown, it can be seen that the regression relationship is good and the prediction accuracy is high.

[0184] Furthermore, the above relationship can be used as a residual heat evaluation model to directly predict the formation residual heat of other oil layers in the target block after multiple rounds of steam stimulation.

[0185] In this scenario example, since as many parameters that affect the residual heat of the oil layer after steam huff and puff development are taken into account as possible, the change of oil layer temperature after steam huff and puff development under different parameters can be simulated, which facilitates the analysis of the sensitivity of oil layer residual heat to different parameters and the change law of oil layer residual heat, and realizes accurate quantitative evaluation of oil layer residual heat.

[0186] Through the above scenario examples, it is verified that the method for determining oil layer waste heat provided in the embodiments of this specification can indeed simplify the data processing process, and accurately and efficiently predict the oil layer waste heat after multiple rounds of steam stimulation development in the target area with a lower data processing volume, so as to more effectively guide the heavy oil development in the target area.

[0187] Although the present specification provides method operation steps as described in the embodiments or flow charts, more or less operation steps may be included based on conventional or non-creative means. The order of steps listed in the embodiments is only one way of executing the order of many steps, and does not represent a unique execution order. When the device or client product in practice is executed, it can be executed in sequence or in parallel according to the method shown in the embodiments or the drawings (for example, a parallel processor or a multi-threaded processing environment, or even a distributed data processing environment). The term "include", "include" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method, product or device including a series of elements includes not only those elements, but also includes other elements that are not explicitly listed, or also includes elements inherent to such a process, method, product or device. In the absence of more restrictions, it is not excluded that there are other identical or equivalent elements in the process, method, product or device including the elements. The first, second, etc. words are used to represent the name, and do not represent any particular order.

[0188] Those skilled in the art also know that, in addition to implementing the controller in a purely computer-readable program code, the controller can be made to implement the same function in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers by logically programming the method steps. Therefore, such a controller can be considered as a hardware component, and the devices for implementing various functions included therein can also be considered as structures within the hardware component. Or even, the devices for implementing various functions can be considered as both software modules for implementing the method and structures within the hardware component.

[0189] This specification may be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, classes, etc. that perform specific tasks or implement specific abstract data types. This specification may also be practiced in distributed computing environments where tasks are performed by remote processing devices connected through a communication network. In a distributed computing environment, program modules may be located in local and remote computer storage media including storage devices.

[0190] Through the description of the above embodiments, it can be known that those skilled in the art can clearly understand that the present specification can be implemented by means of software plus a necessary general hardware platform. Based on such an understanding, the technical solution of the present specification can essentially be embodied in the form of a software product, which can be stored in a storage medium such as ROM / RAM, a disk, an optical disk, etc., and includes a number of instructions for enabling a computer device (which can be a personal computer, a mobile terminal, a server, or a network device, etc.) to execute the methods described in each embodiment of the present specification or some parts of the embodiments.

[0191] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. This specification can be used in many general or special computer system environments or configurations. For example: personal computers, server computers, handheld devices or portable devices, tablet devices, multi-processor systems, microprocessor-based systems, set-top boxes, programmable electronic devices, network PCs, minicomputers, mainframe computers, distributed computing environments including any of the above systems or devices, etc.

[0192] Although the present specification is described through embodiments, persons skilled in the art will appreciate that there are many variations of the present specification without departing from the spirit of the present specification, and it is intended that the appended claims include these variations without departing from the spirit of the present specification.

Claims

1. A method for determining residual heat of an oil layer, characterized in that: include: Obtaining target reservoir static parameters, target fluid physical property parameters and target operating parameters related to the target area; wherein the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters and the parameter types of the target operating parameters are determined in advance by a preset sensitivity analysis based on a preset multiple rounds of steam huff-and-puff development simulation of a reference well; the parameter types of the target reservoir static parameters include: porosity and reservoir height; the parameter types of the target fluid physical property parameters include: permeability; the parameter types of the target operating parameters include: steam dryness, injection temperature and cumulative injection volume; The target reservoir static parameters, target fluid physical property parameters and target operating parameters are processed by using the formation residual heat prediction model to obtain a target prediction result; wherein the formation residual heat prediction model is established in advance by using the target reservoir static parameters, target fluid physical property parameters and target operating parameters of a reference well; Based on the target prediction results, determine the residual heat of the oil layer after multiple rounds of steam stimulation and puffing development in the target area; The target reservoir static parameters, target fluid physical property parameters and target operating parameters are processed by the formation residual heat prediction model to obtain the target prediction result, including: processing the target reservoir static parameters, target fluid physical property parameters and target operating parameters by the formation residual heat prediction model according to the following formula: Among them, Er is the prediction result of the residual heat of the oil layer after multiple rounds of steam stimulation and puffing in the target area, k o is the permeability, H is the reservoir height, φ is the porosity, x is the steam quality, T inj is the injection temperature, Q ac is the cumulative injection volume.

2. The method according to claim 1, characterized in that: The method further comprises: The parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters and the parameter types of the target operating parameters are determined by performing a preset sensitivity analysis based on a preset multiple rounds of steam stimulation development simulation of a reference well in the following manner: Acquiring a first reservoir static parameter, a first fluid physical property parameter, and a first operating parameter of a reference well; According to the first reservoir static parameter, the first fluid physical property parameter and the first operation parameter of the reference well, a preset multiple rounds of steam huff and puff development simulation is performed to obtain the temperature distribution of the reference well after the multiple rounds of steam huff and puff development simulation; According to the temperature distribution after multiple rounds of steam huff and puff development simulation of the reference well, the residual heat of the oil layer after multiple rounds of steam huff and puff development simulation of the reference well is calculated; According to the residual heat of the oil layer after multiple rounds of steam huff-and-puff development simulation of the reference well, by performing a preset sensitivity analysis, the parameter types of the first reservoir static parameters, the parameter types of the first fluid physical property parameters and the parameter types of the first operating parameters are respectively screened out.

3. The method according to claim 2, characterized in that According to the temperature distribution of the reference well after multiple rounds of steam huff and puff development simulation, the residual heat of the oil layer after multiple rounds of steam huff and puff development simulation of the reference well is calculated, including: According to the following formula, the residual heat of the oil layer after multiple rounds of steam stimulation and puffing development simulation of the reference well is calculated: Among them, Er′ is the residual heat of the oil layer after multiple rounds of steam stimulation and development simulation of the reference well, r is the distance between the position point in the oil layer of the reference well and the center of the reference well, h is the thickness of the oil layer, T r The temperature after multiple cycles of steam stimulation and puffing at the location in the reservoir of the reference well, T i is the initial temperature of the reference well in the oil layer, φ is the porosity, C o is the specific heat capacity of crude oil, S o is the saturation of crude oil, ρ o is the density of crude oil, C w is the specific heat capacity of water, S w is the water saturation, ρ w is the density of water, C r is the specific heat capacity of rock, ρ r is the density of the rock.

4. The method according to claim 2, characterized in that According to the residual heat of the oil layer after multiple rounds of steam huff-and-puff development simulation of the reference well, by performing a preset sensitivity analysis, the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters and the parameter types of the target operating parameters are screened out from the parameter types of the first reservoir static parameters, the parameter types of the first fluid physical property parameters and the parameter types of the first operating parameters, including: According to the residual heat of the oil layer after multiple rounds of steam huff-and-puff development simulation of the reference well, an orthogonal test is performed on the parameters of the first reservoir static parameter, the first fluid physical property parameter and the first operation parameter of the reference well to obtain the corresponding test results; According to the test results, by performing range analysis and variance analysis, the parameter types of the first reservoir static parameters, the parameter types of the first fluid physical property parameters and the parameter types of the first operating parameters are respectively screened out to select the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters and the parameter types of the target operating parameters that meet the requirements.

5. The method according to claim 2, characterized in that: The method further comprises: The formation residual heat prediction model is established using the target reservoir static parameters, target fluid physical property parameters and target operation parameters of the reference well in the following manner: Obtain target reservoir static parameters, target fluid physical property parameters and target operation parameters of the reference well; Using the target reservoir static parameters, target fluid physical property parameters and target operating parameters of the reference well, as well as the oil layer residual heat after multiple rounds of steam stimulation development simulation of the reference well, a multivariate linear regression is performed to construct a formation residual heat prediction model.

6. The method according to claim 1, characterized in that After determining the residual heat of the oil layer after multiple rounds of steam stimulation and puffing development in the target area, the method further includes: According to the residual heat of the oil layer after multiple rounds of steam huff and puff development in the target area, determine the development strategy that matches the later stage of multiple rounds of steam huff and puff development in the target area; Based on the development strategy that matches the late stage of multiple rounds of steam stimulation development in the target area, heavy oil development is carried out in the target area.

7. A device for determining residual heat of an oil layer, characterized in that: include: An acquisition module is used to acquire target reservoir static parameters, target fluid physical property parameters and target operation parameters related to the target area; wherein the parameter types of the target reservoir static parameters, the parameter types of the target fluid physical property parameters and the parameter types of the target operation parameters are determined in advance by performing a preset sensitivity analysis after a preset multiple rounds of steam huff-and-puff development simulation based on a reference well; the parameter types of the target reservoir static parameters include: porosity and reservoir height; the parameter types of the target fluid physical property parameters include: permeability; the parameter types of the target operation parameters include: steam dryness, injection temperature and cumulative injection volume; A processing module, used for processing the target reservoir static parameters, target fluid physical property parameters and target operating parameters by using the formation residual heat prediction model to obtain a target prediction result; wherein the formation residual heat prediction model is established in advance by using the target reservoir static parameters, target fluid physical property parameters and target operating parameters of a reference well; A determination module is used to determine the residual heat of the oil layer after multiple rounds of steam stimulation development in the target area according to the target prediction results; The processing module is specifically used to process the target reservoir static parameters, target fluid physical property parameters and target operation parameters using the formation residual heat prediction model according to the following formula: Among them, Er is the prediction result of the residual heat of the oil layer after multiple rounds of steam stimulation and puffing in the target area, k o is the permeability, H is the reservoir height, φ is the porosity, x is the steam quality, T inj is the injection temperature, Q ac is the cumulative injection volume.

8. A computer-readable storage medium, characterized in that: Computer instructions are stored thereon, and when the instructions are executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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