A method and device for evaluating injection-production balance of a water drive reservoir

Abstract

This invention discloses a method and apparatus for evaluating the injection-production balance in water-drive reservoirs. The method includes: dimensionally processing the production / water absorption and perforation production thickness of oil wells and water wells at a specified time period to obtain the dimensionless perforation production thickness ratio and the production / water absorption ratio of each layer; determining the ratio of the dimensionless production ratio to the dimensionless perforation production thickness ratio of the oil well layers as the production balance parameter, thus obtaining a production balance parameter set; and determining the ratio of the dimensionless water absorption ratio to the dimensionless perforation production thickness ratio of the water well layers as the injection balance parameter, thus obtaining an injection balance parameter set; and evaluating the degree of injection-production balance in the reservoir at a specified time period based on the statistical results of the production balance parameter set and the injection balance parameter set. This method can quantitatively characterize the degree of injection-production balance in the reservoir using the dimensionless production balance parameters of each oil well layer and the injection balance parameters of each water well layer.

Description

Technical Field

[0001] This invention relates to the field of reservoir development technology, and in particular to a method and apparatus for evaluating the injection-production balance in water-drive reservoirs. Background Technology

[0002] As domestic old oilfields gradually enter the "high-yield and high-quality" and "extremely high-yield and high-quality" stages, the remaining oil is generally dispersed but locally concentrated, making further potential tapping increasingly difficult. Development adjustments are increasingly focused on refinement and precision, with the remaining oil between wells and within reservoirs becoming the primary targets for potential tapping and well network adjustments in old oilfields. The "high-yield and high-quality" and "extremely high-yield and high-quality" development stages place higher demands on dynamic monitoring of oilfield development. Oilfield development urgently needs a reasonable injection-production balance evaluation system to quantitatively characterize the uniformity of reservoir displacement, assess the development level and the suitability of the well network, and provide a theoretical basis for formulating further development adjustment strategies, truly realizing the transformation of oilfield development from refinement to precision.

[0003] Currently, the oil industry typically uses the degree of water drive control and the degree of water drive utilization to evaluate the equilibrium of water drive utilization. Although this has provided great help in stratified water injection management, it also has certain limitations. Summary of the Invention

[0004] The inventors discovered that existing water drive control evaluation technologies only represent the static perforation status of oil and water wells, and can only evaluate the degree of perforation correspondence from a static perspective. Water drive utilization evaluation also only characterizes the thickness ratio of the water-absorbing layer, lacking consideration of water absorption, while the water absorption of each sub-layer is the true indicator of the uniform displacement level of water drive; therefore, it can only provide a fuzzy characterization of inter-layer contradictions and whether or not water is utilized, lacking accuracy. Furthermore, the production status of each sub-layer at the oil well end and the water absorption status of each sub-layer at the water well end have been evaluated using isolated systems without establishing a connection, making it impossible to characterize the uniformity of water drive on a planar surface. The characterization of dynamic planar contradictions in water drive utilization is still lacking, which brings great inconvenience to reservoir development and adjustment.

[0005] In order to at least partially solve the problems existing in the prior art, the inventors made this invention, which, through specific embodiments, provides a method and apparatus for evaluating the injection-production balance of a water-driven oil reservoir, which can reasonably and quantitatively characterize the degree of injection-production balance in the reservoir.

[0006] In a first aspect, embodiments of the present invention provide a method for evaluating the injection-production balance in water-drive reservoirs, comprising:

[0007] The production volume of oil wells, the water absorption of water wells, and the perforation production thickness of oil wells and water wells in the reservoir at a set time were dimensionless to obtain the dimensionless production volume ratio of oil wells, the dimensionless water absorption ratio of water wells, and the dimensionless perforation production thickness ratio of oil wells and water wells.

[0008] The ratio of the dimensionless fluid production rate of the oil well sublayer to the dimensionless perforation production thickness is determined as the production equilibrium parameter of the sublayer, thus obtaining the production equilibrium parameter set for the reservoir at a set time. The ratio of the dimensionless water absorption rate of the water well sublayer to the dimensionless perforation production thickness is determined as the injection equilibrium parameter of the sublayer, thus obtaining the injection equilibrium parameter set for the reservoir at a set time.

[0009] The degree of injection-production balance in the reservoir during the specified period is evaluated based on the statistical results of the production balance parameter set and the injection balance parameter set.

[0010] Secondly, embodiments of the present invention provide a device for evaluating the injection-production balance of a water-drive reservoir, comprising:

[0011] The dimensionless processing module is used to perform dimensionless processing on the production volume of oil well sublayers, the water absorption volume of water well sublayers, and the perforation production thickness of oil wells and water well sublayers at a set time in the reservoir, respectively, to obtain the dimensionless production volume ratio of oil well sublayers, the dimensionless water absorption ratio of water well sublayers, and the dimensionless perforation production thickness ratio of oil wells and water well sublayers.

[0012] The injection-production balance parameter set acquisition module is used to determine the production balance parameter of the oil well by the ratio of the dimensionless production volume of the small layer to the ratio of the dimensionless perforation production thickness, and obtain the production balance parameter set of the reservoir for a set period. The module also determines the injection balance parameter of the water well by the ratio of the dimensionless water absorption volume of the small layer to the ratio of the dimensionless perforation production thickness, and obtains the injection balance parameter set of the reservoir for a set period.

[0013] The injection-production balance evaluation module is used to evaluate the injection-production balance of the reservoir during the specified period based on the statistical results of the production balance parameter set and the injection balance parameter set.

[0014] Thirdly, embodiments of the present invention provide a computer program product, including a computer program / instruction, wherein the computer program / instruction, when executed by a processor, implements the above-mentioned method for evaluating the injection-production balance of water-driven reservoirs.

[0015] Fourthly, this disclosure provides a server, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the above-described method for evaluating the injection-production balance of water-driven reservoirs.

[0016] The beneficial effects of the above-described technical solutions provided in the embodiments of the present invention include at least the following:

[0017] (1) The water-drive reservoir injection-production balance evaluation method provided in this embodiment of the invention performs dimensionless processing on the production / water absorption and perforation production thickness of the sub-layer, respectively, to obtain the dimensionless production ratio of the oil well sub-layer, the dimensionless water absorption ratio of the water well sub-layer, and the dimensionless perforation production thickness ratio of the sub-layer; then, the ratio of the dimensionless production ratio of the oil well sub-layer to the dimensionless perforation production thickness ratio is determined as the production balance parameter of the sub-layer, and the ratio of the dimensionless water absorption ratio of the water well sub-layer to the dimensionless perforation production thickness ratio is determined as the injection balance parameter of the sub-layer. The production balance parameter can be used to evaluate the production balance of the sub-layer. The degree of injection balance can be quantitatively characterized by injection balance parameters. Based on the statistical results of the production balance parameter set and the injection balance parameter set, the degree of injection-production balance of the reservoir in a given period is evaluated, realizing the quantitative characterization of the reservoir's injection-production balance. On this basis, the horizontal and vertical injection-production balance of the reservoir as a whole can be characterized, clarifying the degree of control and utilization of the underground reservoir by the current well network and production system, analyzing the contradictions between development and production, and evaluating the reservoir development level and the applicability of the well network, providing a theoretical basis for formulating development adjustment strategies in the next step.

[0018] (2) The water-drive reservoir injection-production balance evaluation method provided in this embodiment of the invention solves the problem that the mechanical error of individual single well measurement data has been large and it is difficult to compare horizontally and vertically and make quantitative evaluation through dimensionless processing and statistical analysis. It also solves the problem that the relative error caused by the low water absorption or production of small layers affects the data analysis.

[0019] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings.

[0020] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0021] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0022] Figure 1 This is a flowchart of the water-drive reservoir injection-production balance evaluation method in Embodiment 1 of the present invention;

[0023] Figure 2 This is a flowchart illustrating the specific implementation of the water-drive reservoir injection-production balance evaluation method in Embodiment 2 of the present invention.

[0024] Figure 3 This is an example diagram of the frequency distribution curve of the injection-mapping equilibrium parameters in an embodiment of the present invention;

[0025] Figure 4 This is a schematic diagram of the structure of the water-drive reservoir injection-production balance evaluation device in an embodiment of the present invention. Detailed Implementation

[0026] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0027] It should be understood that the terminology used herein is merely for describing particular embodiments and is not intended to limit the invention. Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0028] To address the problem in existing technologies that cannot reasonably and quantitatively evaluate the injection-production balance of water-driven reservoirs, this invention provides a method and apparatus for evaluating the injection-production balance of water-driven reservoirs, which can quantitatively characterize the degree of injection-production balance in the reservoir.

[0029] Example 1

[0030] Embodiment 1 of the present invention provides a method for evaluating the injection-production balance in water-drive reservoirs, the process of which is as follows: Figure 1 As shown, it includes the following steps:

[0031] Step S11: Dimensionally transform the production volume of oil well sublayers, the water absorption volume of water well sublayers, and the perforation production thickness of oil wells and water wells for a given period in the reservoir to obtain the dimensionless production volume ratio of oil well sublayers, the dimensionless water absorption volume ratio of water well sublayers, and the dimensionless perforation production thickness ratio of oil wells and water wells.

[0032] The set period can include at least one test period. The production volume of the oil well sub-layer can be obtained from the oil well production profile test data, and the water absorption volume of the water well sub-layer can be obtained from the water absorption profile test data. The perforation production thickness of the sub-layer is the perforation production thickness at the time of a single test. The data that needs to be dimensionless includes the production volume of each sub-layer of the oil well, the water absorption volume of each sub-layer of the water well, and the perforation production thickness of each sub-layer of the oil well and water well obtained in each test period.

[0033] Production and water absorption profile testing of oil and water wells in oilfields is an important means of monitoring the flow conditions of different layers and perforations in oil and water wells. It characterizes the absolute value of the underground flow generated under the test conditions. However, since the test conditions may not perfectly match the pressure conditions during production, the absolute production cannot completely and accurately represent the corresponding layered production of underground flow during normal production. However, the relative magnitudes between production data can effectively characterize the non-uniformity of underground flow. Therefore, we first perform dimensionless processing on the production and water absorption for each layer, and then perform dimensionless production calculations for different perforation sections for the current well test.

[0034] Dimensionless processing may include dimensionless processing of the production volume of oil well sublayers, the water absorption volume of water well sublayers, and the perforation production thickness of oil wells and water well sublayers at a specified time period in the reservoir, respectively, on a single well basis.

[0035] Furthermore, according to the different test periods, the oil well production, water absorption, and perforation production thickness of each reservoir layer obtained in each test period are dimensionlessly processed on a single well basis.

[0036] First, based on the production rate of the oil well sublayer during each test at a set reservoir period, the total production rate for each oil well in the corresponding test cycle is determined. Then, based on the water absorption rate of the water well sublayer during each test, the total water absorption rate for each water well in the corresponding test cycle is determined. Finally, based on the perforation production thickness of the sublayer during each test, the total perforation production thickness for each oil well and each water well is determined. The data is then dimensionlessly processed using the following steps:

[0037] (1) The ratio of the single test production of a small layer of oil well to the total production of the oil well in that test is determined as the dimensionless production ratio of that small layer.

[0038] (2) The ratio of the water absorption of a single test of a water well layer to the total water absorption of the water well in that test is the dimensionless water absorption ratio of that layer.

[0039] (3) The ratio of the perforated production thickness of a small layer during a single test to the total perforated production thickness of the oil well or water well containing that small layer during that test is determined as the dimensionless perforated production thickness percentage of that small layer.

[0040] Step S12: Determine the ratio of the dimensionless production volume of the oil well layer to the ratio of the dimensionless perforation production thickness as the production equilibrium parameter of the layer, and obtain the production equilibrium parameter set for the reservoir at a set time.

[0041] Step S13: Determine the ratio of the dimensionless water absorption of the water well layer to the ratio of the dimensionless perforation production thickness as the injection equilibrium parameter of the layer, and obtain the injection equilibrium parameter set for the reservoir at a set time.

[0042] Under ideal conditions, neglecting interlayer heterogeneity, if injection-production equilibrium is achieved, the dimensionless production rate of an oil well layer should be exactly the same as the dimensionless perforation production thickness, and similarly, the dimensionless water absorption rate of a water well layer should also be exactly the same. However, in actual production, due to differences in static parameters (permeability, capillary pressure, wettability) and dynamic conditions (pressure, saturation) between layers, as well as differences between water wells (or oil wells) on the same plane, the dimensionless ratio between the dimensionless production rate of an oil well layer and the dimensionless perforation production thickness is often not equal to 1. The magnitude of this deviation from 1 can be used to represent the difference between the production rate of that layer and the ideal condition, and thus can be used as a production equilibrium parameter for that layer. Similarly, the dimensionless ratio between the dimensionless water absorption rate of a water well layer and the dimensionless perforation production thickness can be used to represent the difference between the injection rate of that layer and the ideal condition, and thus can be used as an injection equilibrium parameter for that layer.

[0043] When the extraction equilibrium parameter (or injection equilibrium parameter) > 1, it indicates that the current product fluid (or water absorption) is higher than the ideal value. This layer belongs to the dominant flow channel, and theoretically, this value can approach infinity. In actual data statistics, cases exceeding 100 are rare. When the extraction equilibrium parameter (or injection equilibrium parameter) < 1, it indicates that the current product fluid (or water absorption) is lower than the ideal value. This layer belongs to the inhibited or poorly functioning layer in the displacement system. Theoretically, this value can approach 0. In actual data statistics, values ​​below 0.01 are close to or exceed the measurement system error value of the testing instrument (this may vary depending on the flow rate).

[0044] Steps S12 and S13 have no specific order; either step can be executed first, or they can be executed simultaneously.

[0045] Step S14: Evaluate the degree of injection-production balance in the reservoir during the set period based on the statistical results of the production balance parameter set and the injection balance parameter set.

[0046] The statistical analysis of the extracted equilibrium parameter set and the injected equilibrium parameter set can be done by plotting the distribution frequency curves of the corresponding parameters or plotting the distribution frequency histograms of the corresponding parameters; alternatively, other statistical methods can also be used.

[0047] In some embodiments, a production equilibrium parameter distribution frequency curve can be plotted based on the production equilibrium parameter set, and an injection equilibrium parameter distribution frequency curve can be plotted based on the injection equilibrium parameter set; the degree of injection-production equilibrium in a reservoir during a set period can be evaluated based on the production equilibrium parameter distribution frequency curve and the injection equilibrium parameter distribution frequency curve.

[0048] Considering the dynamic and static heterogeneity, the dimensionless injection equilibrium parameter (or production equilibrium parameter) is distributed from 0 to +∞. To facilitate observation, analysis, and quantitative evaluation, the injection equilibrium parameter and production equilibrium parameter are logarithmically processed to base 10. After processing, the original production equilibrium parameter (or production equilibrium parameter) λ range changes from 0 to +∞ to -∞ to +∞ of lgλ. lgλ is symmetrically distributed with 0 as the median. lgλ = 0 is exactly the ideal value of injection-production equilibrium when λ = 1. The cases where λ is 0.01 times and 100 times the ideal value correspond to the cases where lgλ is -2 and 2 respectively, which precisely reflect the actual parameter distribution.

[0049] In some embodiments, the degree of injection-production balance in a reservoir during a set period is evaluated based on the production balance parameter distribution frequency curve and the injection balance parameter distribution frequency curve. This may specifically include performing at least one of the following:

[0050] (1) Determine at least one of the following pieces of information from the frequency distribution curve of the production equilibrium parameter to evaluate the degree of production equilibrium of the reservoir during a given period:

[0051] Peak value, set percentile, distribution width of the set proportion parameter determined by the set percentile.

[0052] Percentiles can be set, including P10, P25, P50, P75, and P90. Optional, other percentiles are also possible.

[0053] The median P50 can characterize the degree of deviation of the test result from the equilibrium line 0. The distribution width of the 80% parameter can also be obtained as: α 80 =P 90 -P 10 The distribution width of 50% of the parameters is α. 50 =P 75 -P 50 .

[0054] (2) Determine at least one of the above information from the frequency curve of the injection equilibrium parameter distribution, and evaluate the degree of injection equilibrium of the reservoir during a set period.

[0055] (3) Evaluate the difference between the production equilibrium degree and the injection equilibrium degree of the reservoir during a set period based on the peak difference between the production equilibrium parameter distribution frequency curve and the injection equilibrium parameter distribution frequency curve and / or the difference in the distribution width of the set ratio parameter.

[0056] The water-drive reservoir injection-production balance evaluation method provided in Embodiment 1 of this invention performs dimensionless processing on the production / water absorption ratio and the perforation production thickness of the sub-layers to obtain the dimensionless production ratio of the oil well sub-layers, the dimensionless water absorption ratio of the water well sub-layers, and the dimensionless perforation production thickness ratio of the sub-layers. Then, the ratio of the dimensionless production ratio to the dimensionless perforation production thickness ratio of the oil well sub-layers is determined as the production balance parameter of the sub-layers, and the ratio of the dimensionless water absorption ratio to the dimensionless perforation production thickness ratio of the water well sub-layers is determined as the injection balance parameter of the sub-layers. The production balance parameters can be used to assess the degree of production balance in the sub-layers. Quantitative characterization is achieved by using injection equilibrium parameters to quantitatively characterize the injection equilibrium degree of a sub-layer. Based on the statistical results of the production equilibrium parameter set and the injection equilibrium parameter set, the injection-production equilibrium degree of the reservoir during a set period is evaluated, realizing the quantitative characterization of the reservoir's injection-production equilibrium degree. Furthermore, based on this, the horizontal and vertical injection-production equilibrium degree of the reservoir as a whole can be characterized, clarifying the degree of control and utilization of the underground reservoir by the current well network and production system, analyzing development and production contradictions, and evaluating the reservoir development level and the applicability of the well network, providing a theoretical basis for formulating development adjustment strategies in the next step.

[0057] By employing dimensionless processing and statistical analysis, the problem of large mechanical errors in individual well measurement data, which has long plagued oilfield development analysis, and the difficulty in making horizontal and vertical comparisons and quantitative evaluations, has been solved. It has also solved the problem of large relative errors affecting data analysis due to low water absorption or production in small layers.

[0058] In some embodiments, the method may further include evaluating the differences in the degree of injection-production balance in different periods of the reservoir by comparing the statistical results of the production balance parameter sets and injection balance parameter sets at different periods of the reservoir development process. This enables a comparative analysis of the degree of injection-production balance at different periods of the reservoir development process.

[0059] In some embodiments, the method may further include evaluating the differences in the degree of injection-production balance among different reservoirs during a set period by comparing the statistical results of the production balance parameter sets and injection balance parameter sets for different reservoirs at a set period. This enables a horizontal comparative analysis of the degree of injection-production balance among different reservoirs in an oilfield.

[0060] Example 2

[0061] Embodiment 2 of the present invention provides a specific implementation process for a method for evaluating the injection-production balance in water-drive reservoirs, such as... Figure 2 As shown, it includes the following steps:

[0062] Step S21: Dimensionless processing of production and water absorption profile test data.

[0063] Collect production / water absorption profile test data from each test period of the reservoir and perforation data of oil wells and water wells put into production during the same period.

[0064] The test production volume of the oil well sublayer, the test water absorption volume of the water well sublayer, and the perforation production thickness of the oil well and water well sublayers during the test were obtained from the above data for each test period.

[0065] Then, the production / water absorption profile test results of each well were dimensionlessly processed to obtain the percentage of production / water absorption of each sub-layer in each test process relative to the total production / water absorption of the well in that test.

[0066]

[0067] Where i represents the oil well / water well number, j represents the test period number, k represents the sub-layer number, and v ijk Q represents the proportion of dimensionless fluid production / water absorption in the k-th layer of the i-th oil / water well during the j-th test. ijk Q represents the test production / water absorption of the kth layer in the j-th test of the i-th oil / water well. sumij This represents the total production / total water absorption of the i-th oil / water well during the j-th test.

[0068] Step S22: Dimensionless treatment of perforation thickness during production liquid and water absorption tests.

[0069] To eliminate the impact of perforation thickness on flow rate and to gain an objective understanding of the liquid production / water absorption of different layers, the thickness ratio of the perforation section during production was calculated for each sub-layer during testing.

[0070]

[0071] Where, α ijk h represents the percentage of dimensionless perforated production thickness in the k-th sublayer of the i-th oil / water well during the j-th test. ijk H represents the perforated production thickness of the k-th sublayer in the i-th oil / water well during the j-th test. sumij This represents the total perforated production thickness of the i-th oil / water well during the j-th test.

[0072] Step S23: Calculation of dimensionless parameters for injection-production balance.

[0073]

[0074] Where, λ ijk This represents the dimensionless parameter of the injection-production balance in the j-th test of the k-th sublayer of the i-th oil / water well. More specifically, if the i-th well is an oil well, λ ijk λ represents the equilibrium dimensionless parameter produced during the j-th test of the k-th sublayer of the i-th oil well; if the i-th well is a water well, λijk This represents the dimensionless parameter of the injection equilibrium in the j-th test of the k-th sublayer of the i-th well.

[0075] Step S24: Dimensionless parameter symmetry processing for injection-production balance.

[0076] The extraction equilibrium dimensionless parameters and the injection equilibrium dimensionless parameters are logarithmically processed to base 10.

[0077] The injection-production balance parameter λ ranges from 0 to +∞. When the parameter is equal to 1, it indicates that the percentage of output / absorption of the layer matches the percentage of perforation production thickness, and the layer is a perforation layer in a "balanced" state. Taking the injection-production balance parameter λ as the logarithm to the base 10, the parameter range is mapped to a symmetrical interval of -∞ to +∞, and the symmetrical point, i.e. the balance point, is 0.

[0078] Step S25: Statistical analysis of the distribution interval of dimensionless parameters for injection-production balance and quantitative evaluation of the degree of injection-production balance.

[0079] Plot the frequency distribution curves of the injection equilibrium dimensionless parameters and the extraction equilibrium dimensionless parameters for each test period. Obtain the P10, P25, P50, P75, and P90 percentiles (including but not limited to these) of the frequency distribution curves. The median P50 can characterize the degree of deviation of the test results from the equilibrium line 0. The width of the most balanced 80% test data distribution is also obtained as follows:

[0080] Δ 80 =P 90 -P 10

[0081] The width of the most balanced 50% test data distribution can be obtained as follows:

[0082] Δ 50 =P 75 -P 50

[0083] The difference in wellhead equilibrium between oil and water wells can be represented by the difference in the bandwidth of the most balanced test data distribution at 80% and / or 50% of the wells:

[0084] Δ 80油水 =Δ 80油 -Δ 80水

[0085] Δ 50油水 =Δ 50油 -Δ 50水

[0086] Based on the above indicators, percentile standards for similar oilfields can be established to conduct horizontal comparisons and quantitative evaluations of the injection-production balance in different oilfields / blocks. For the same block at different development stages, by comparing the changes in the above parameters, the process of changes in the injection-production balance in that block can be analyzed.

[0087] The method disclosed in Embodiment 2 of this invention uses water absorption and production profile test data to characterize the equilibrium of reservoir displacement mobilization. It can simultaneously describe the degree of equilibrium of horizontal and vertical mobilization, clarify the degree of control and mobilization of underground reservoirs by the current well network and production system, analyze the contradiction between development and production, evaluate the reservoir development level and the applicability of the well network, and provide a basis for determining the production system and formulating development adjustment strategies.

[0088] Following the above technical process, an evaluation of the injection-production balance status was conducted using a specific oilfield block as an example. A schematic diagram of the frequency distribution curves of dimensionless injection-production balance parameters is shown below. Figure 3 As shown, the distribution of small-layer intake parameters is the frequency distribution curve of the dimensionless parameters of injection equilibrium, and the distribution of small-layer production parameters is the frequency distribution curve of the dimensionless parameters of production equilibrium. It is evident that, through years of effective stratified water injection management, the water injection equilibrium of the oilfield has been well controlled. Considering the differences in permeability and heterogeneity among layers, the small-layer sample data obtained from each test at the water injection wellhead are closely symmetrically distributed around the equilibrium line, resulting in a high peak value in the frequency distribution curve and a narrow interval between the 10th and 90th percentiles. Simultaneously, due to the non-uniformity of underground flow at the oil wellhead, the water intake in each layer mainly flows towards the dominant seepage direction. Therefore, the distribution curve of the equilibrium status evaluation at the production wellhead is lower than that at the water wellhead, indicating that there are more layers at the production wellhead with mismatched production and thickness, resulting in a large number of layers with excessively high and low production. According to... Figure 3 It can be seen that the water injection end of the block is in good balance and meets the requirements of stratified water injection index, but the output end is still highly unbalanced, indicating that there is a serious imbalance in planar displacement at present. The next step should focus on planar displacement control to tap the remaining oil generated by the differences in flow direction.

[0089] Based on the inventive concept of this invention, embodiments of this invention also provide a device for evaluating the injection-production balance of water-drive reservoirs, the structure of which is as follows: Figure 4 As shown, it includes:

[0090] The dimensionless processing module 41 is used to perform dimensionless processing on the production volume of oil well sublayer, the water absorption volume of water well sublayer, and the perforation production thickness of oil well and water well sublayer at a set time in the reservoir, respectively, to obtain the dimensionless production volume ratio of oil well sublayer, the dimensionless water absorption ratio of water well sublayer, and the dimensionless perforation production thickness ratio of oil well and water well sublayer.

[0091] The injection-production balance parameter set acquisition module 42 is used to determine the ratio of the dimensionless production volume ratio of the oil well sublayer to the dimensionless perforation production thickness ratio as the sublayer production balance parameter, and obtain the production balance parameter set for the reservoir set period. It also determines the ratio of the dimensionless water absorption volume ratio of the water well sublayer to the dimensionless perforation production thickness ratio as the sublayer injection balance parameter, and obtains the injection balance parameter set for the reservoir set period.

[0092] The injection-production balance evaluation module 43 is used to evaluate the injection-production balance of the reservoir during the specified period based on the statistical results of the production balance parameter set and the injection balance parameter set.

[0093] Regarding the apparatus in the above embodiments, the specific manner in which each module performs its operation has been described in detail in the embodiments related to the method, and will not be elaborated upon here.

[0094] Based on the inventive concept of the present invention, embodiments of the present invention also provide a computer program product, including a computer program / instruction, wherein the computer program / instruction, when executed by a processor, implements the above-mentioned method for evaluating the injection-production balance of water-driven reservoirs.

[0095] Unless otherwise specifically stated, terms such as processing, calculation, operation, determination, display, etc., may refer to the actions and / or processes of one or more processing or computing systems or similar devices that represent the manipulation and conversion of data representing physical (e.g., electronic) quantities within the registers or memory of the processing system into other data similarly representing physical quantities within the memory, registers, or other such information storage, transmission, or display devices of the processing system. Information and signals can be represented using any of a variety of different techniques and methods. For example, data, instructions, commands, information, signals, bits, symbols, and chips mentioned throughout the above description can be represented by voltage, current, electromagnetic waves, magnetic fields or particles, light fields or particles, or any combination thereof.

[0096] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process may be rearranged without departing from the scope of this disclosure. The appended method claims provide elements of various steps in an exemplary order and are not intended to limit the scope to the specific order or hierarchy described.

[0097] In the detailed description above, various features are combined together in a single embodiment to simplify this disclosure. This approach to disclosure should not be construed as reflecting an intention that embodiments of the claimed subject matter require more features than are explicitly stated in each claim. Rather, as reflected in the appended claims, the invention is presented with fewer features than all of the features in a single disclosed embodiment. Therefore, the appended claims are hereby explicitly incorporated into the detailed description, with each claim representing a separate preferred embodiment of the invention.

[0098] Those skilled in the art will also understand that the various illustrative logic blocks, modules, circuits, and algorithm steps described in conjunction with the embodiments herein can be implemented as electronic hardware, computer software, or a combination thereof. To clearly illustrate the interchangeability between hardware and software, the various illustrative components, blocks, modules, circuits, and steps described above are generally described in terms of their functionality. Whether such functionality is implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system. Those skilled in the art can implement the described functionality in alternative ways for each specific application; however, such implementation decisions should not be construed as departing from the scope of this disclosure.

[0099] The steps of the methods or algorithms described in conjunction with the embodiments herein can be directly embodied in hardware, software modules executed by a processor, or a combination thereof. The software modules can reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disks, removable disks, CD-ROMs, or any other form of storage medium well known in the art. An exemplary storage medium is connected to the processor, enabling the processor to read information from and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and storage medium can reside in an ASIC. The ASIC can reside in a user terminal. Alternatively, the processor and storage medium can exist as discrete components in the user terminal.

[0100] For software implementation, the techniques described in this application can be implemented using modules (e.g., procedures, functions, etc.) that perform the functions described in this application. This software code can be stored in memory units and executed by a processor. The memory units can be implemented within the processor or outside the processor; in the latter case, they are communicatively coupled to the processor via various means, as is well known in the art.

[0101] The foregoing description includes examples of one or more embodiments. It is certainly impossible to describe all possible combinations of components or methods in order to describe the above embodiments, but those skilled in the art will recognize that further combinations and arrangements of the various embodiments are possible. Therefore, the embodiments described herein are intended to cover all such changes, modifications, and variations that fall within the scope of the appended claims. Furthermore, the term "comprising" as used in the specification or claims is interpreted in a manner similar to the term "including," just as "including" is interpreted as a conjunction in the claims. Additionally, the use of any term "or" in the specification of the claims is intended to mean "non-exclusive or."

Claims

1. A method for evaluating water drive reservoir injection-production balance, characterized in that, include: The production volume of oil well sublayers, the water absorption of water well sublayers, and the perforation production thickness of oil wells and water wells at a specified time period in the reservoir were dimensionlessly processed to obtain the dimensionless production volume ratio of oil well sublayers, the dimensionless water absorption ratio of water well sublayers, and the dimensionless perforation production thickness ratio of oil wells and water wells. This includes: determining the dimensionless production volume ratio of an oil well sublayer as the ratio of the production volume of a single test to the total production volume of the oil well containing that sublayer in that test; determining the dimensionless water absorption ratio of a water well sublayer as the ratio of the water absorption of a single test to the total water absorption of the water well containing that sublayer in that test; and determining the dimensionless perforation production thickness ratio of a sublayer as the ratio of the perforation production thickness of a sublayer in a single test to the total perforation production thickness of the oil well or water well containing that sublayer in that test. The ratio of the dimensionless fluid production rate of the oil well sublayer to the dimensionless perforation production thickness is determined as the production equilibrium parameter of the sublayer, thus obtaining the production equilibrium parameter set for the reservoir at a set time. The ratio of the dimensionless water absorption rate of the water well sublayer to the dimensionless perforation production thickness is determined as the injection equilibrium parameter of the sublayer, thus obtaining the injection equilibrium parameter set for the reservoir at a set time. The degree of injection-production balance in the reservoir during the specified period is evaluated based on the statistical results of the production balance parameter set and the injection balance parameter set.

2. The method of claim 1, wherein, The dimensionless processing of the production volume of oil well sublayers, the water absorption of water well sublayers, and the perforation production thickness of oil wells and water well sublayers at a specified time period in the reservoir specifically includes: The production volume of oil wells, the water absorption of water wells, and the perforation production thickness of oil wells and water wells in the reservoir at a given time period were dimensionlessly processed on a single well basis.

3. The method of claim 2, wherein, The process of dimensionlessly processing the production volume of oil well sublayers, the water absorption volume of water well sublayers, and the perforation production thickness of oil wells and water wells at a specified time period in the reservoir yields the dimensionless production volume ratio of oil well sublayers, the dimensionless water absorption ratio of water well sublayers, and the dimensionless perforation production thickness ratio of oil wells and water wells. Specifically, this includes: Based on the oil well production, water absorption, and perforation production thickness of the oil and water wells in each test at a set reservoir period, the total production and perforation production thickness of each oil well, as well as the total water absorption and perforation production thickness of each water well, are determined respectively. The ratio of the single test production of a small oil well layer to the total production of the oil well containing that layer in that test is determined as the dimensionless production percentage of that layer. The ratio of the water absorption of a single test of a water well layer to the total water absorption of the water well containing that layer in that test is determined as the dimensionless water absorption percentage of that layer. The ratio of the perforated production thickness of a sub-layer during a single test to the total perforated production thickness of the oil or water well containing that sub-layer during the same test is determined as the dimensionless perforated production thickness percentage of that sub-layer.

4. The method as described in claim 1, characterized in that, Based on the statistical results of the production equilibrium parameter set and the injection equilibrium parameter set, the degree of injection-production equilibrium of the reservoir during the specified period is evaluated, specifically including: Based on the set of extraction equilibrium parameters, draw the frequency distribution curve of extraction equilibrium parameters; based on the set of injection equilibrium parameters, draw the frequency distribution curve of injection equilibrium parameters. The degree of injection-production balance in the reservoir during the specified period is evaluated based on the frequency distribution curves of the production balance parameters and the injection balance parameters.

5. The method of claim 4, wherein, After determining the ratio of the dimensionless production volume of the oil well sub-layer to the dimensionless perforation production thickness as the sub-layer production equilibrium parameter, the method further includes: The extraction equilibrium parameters are logarithmically reduced to base 10; correspondingly, After determining the ratio of the dimensionless water absorption ratio of the water well sublayer to the dimensionless perforation production thickness ratio as the injection equilibrium parameter of the sublayer, the method further includes: The injection balancing parameters are logarithmically processed to base 10.

6. The method of claim 5, wherein, The step of evaluating the injection-production balance degree of the reservoir during the specified period based on the production balance parameter distribution frequency curve and the injection balance parameter distribution frequency curve specifically includes performing at least one of the following: To evaluate the degree of production equilibrium of the reservoir during the specified period, at least one of the following pieces of information is determined from the frequency distribution curve of the production equilibrium parameter: Peak value, set percentile, distribution width based on the set percentage parameter determined by the set percentile; Determine at least one of the above-mentioned pieces of information from the frequency distribution curve of the injection equilibrium parameter, and evaluate the degree of injection equilibrium of the reservoir during the period. The difference between the production equilibrium degree and the injection equilibrium degree of the reservoir during the specified period is evaluated based on the peak value difference between the production equilibrium parameter distribution frequency curve and the injection equilibrium parameter distribution frequency curve, and / or the distribution width difference of the set ratio parameter.

7. The method as described in claim 6, characterized in that, The setting of percentiles specifically includes: P10, P25, P50, P75, and P90; correspondingly, The distribution width of the set proportion parameter determined according to the set percentile specifically includes: The distribution width of 80% of the parameters determined by P90 and P10, and the distribution width of 50% of the parameters determined by P75 and P25.

8. The method according to any one of claims 1 to 7, characterized in that, Also includes: Based on the comparison of statistical results of the production equilibrium parameter set and injection equilibrium parameter set of the reservoir at different periods, the differences in the degree of injection-production equilibrium of the reservoir at different periods are evaluated.

9. The method according to any one of claims 1 to 7, wherein Also includes: Based on the comparison of statistical results of the production equilibrium parameter set and injection equilibrium parameter set of different reservoirs at the specified time period, the differences in the degree of injection-production equilibrium of different reservoirs at the specified time period are evaluated.

10. A device for evaluating water drive reservoir injection-production balance conditions, characterized by, include: The dimensionless processing module is used to dimensionally process the production volume of oil well sublayers, the water absorption volume of water well sublayers, and the perforation production thickness of oil wells and water wells at a specified time in the reservoir, respectively, to obtain the dimensionless production volume ratio of oil well sublayers, the dimensionless water absorption volume ratio of water well sublayers, and the dimensionless perforation production thickness ratio of oil wells and water well sublayers. Specifically, it is used to determine the dimensionless production volume ratio of an oil well sublayer as the ratio of the production volume of a single test to the total production volume of the oil well containing that sublayer in that test; the dimensionless water absorption volume ratio of a water well sublayer as the ratio of the water absorption volume of a single test to the total water absorption volume of the water well containing that sublayer in that test; and the dimensionless perforation production thickness ratio of a sublayer as the ratio of the perforation production thickness of a sublayer in a single test to the total perforation production thickness of the oil well or water well containing that sublayer in that test. The injection-production balance parameter set acquisition module is used to determine the production balance parameter of the oil well by the ratio of the dimensionless production volume of the small layer to the ratio of the dimensionless perforation production thickness, and obtain the production balance parameter set of the reservoir for a set period. The module also determines the injection balance parameter of the water well by the ratio of the dimensionless water absorption volume of the small layer to the ratio of the dimensionless perforation production thickness, and obtains the injection balance parameter set of the reservoir for a set period. The injection-production balance evaluation module is used to evaluate the injection-production balance of the reservoir during the specified period based on the statistical results of the production balance parameter set and the injection balance parameter set.

11. A computer program product comprising computer programs / instructions, characterized in that, When the computer program / instruction is executed by the processor, it implements the water-drive reservoir injection-production balance evaluation method as described in any one of claims 1 to 9.

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