Calculation method for horizontal well inter-section interference coefficient based on integration of multiple factors

Abstract

The invention discloses a horizontal well inter-section interference coefficient calculation method integrating multiple factors. The method comprises the steps that differential pressure, permeability, fluid viscosity, interlayer distribution and injection-production ratio data are collected; calculating a permeability variation coefficient, a viscosity ratio and an injection-production ratio deviation coefficient; calculating a permeability difference, a fluid viscosity difference, oil reservoir heterogeneity and a well pattern arrangement correction coefficient according to correction coefficients determined by experiment or historical data; calculating a traditional inter-segment interference coefficient based on the pressure difference; and integrating the correction coefficient and the pressure difference coefficient to obtain a multi-factor inter-segment interference coefficient, and the like. According to the method, the calculation precision is remarkably improved, scientific decision is supported, parameters can be flexibly adjusted to adapt to different oil reservoir environments, inter-section interference is effectively reduced, and the recovery efficiency is improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of oilfield development, and particularly relates to a multi-factor comprehensive horizontal well section interference coefficient calculation method. BACKGROUND

[0002] In the process of oil exploitation, horizontal well technology is widely used in major oilfields due to its advantages of increasing oil layer drainage area and improving single well production. However, the problem of horizontal well section interference seriously restricts the efficient development of oil reservoirs. At present, the traditional horizontal well section interference coefficient calculation method mainly focuses on the pressure difference factor, that is, only the pressure difference between the target section and the adjacent section of the horizontal well and the total pressure drop of the horizontal well are used to calculate the section interference coefficient.

[0003] This single-factor calculation method has obvious defects. It ignores the comprehensive influence of many key factors such as permeability difference, fluid properties, reservoir heterogeneity, well pattern arrangement and production methods on section interference. In actual reservoir environment, these ignored factors often play a crucial role in section interference. For example, permeability difference can cause a huge difference in fluid flow capacity in different well sections, thereby exacerbating section interference; the difference in fluid properties, such as viscosity difference, can change the flow resistance and speed of the fluid, thereby affecting the pressure distribution and interference degree between sections.

[0004] Because the traditional calculation method cannot accurately reflect the actual section interference, the production strategy based on it often lacks scientificity and effectiveness, and it is difficult to achieve the goal of reducing section interference and improving oil recovery. Therefore, it is urgent to develop a multi-factor comprehensive horizontal well section interference coefficient calculation method. SUMMARY

[0005] The application is proposed to solve the problems in the prior art, and aims to provide a multi-factor comprehensive horizontal well section interference coefficient calculation method.

[0006] The application is implemented by the following technical scheme: A multi-factor comprehensive horizontal well section interference coefficient calculation method, comprising the following steps: S1, collecting basic data; The basic data includes the pressure difference between the target section and the adjacent section of the horizontal well, the total pressure drop of the horizontal well, the permeability, the fluid viscosity of the target section, the fluid viscosity of the adjacent section, the interlayer influence coefficient and the injection-production ratio; Specifically, the following steps are included: S11, using a high-precision and high-stability pressure sensor, according to the specified time interval and measurement method, the pressure difference between the target section and the adjacent section of the horizontal well and the total pressure drop of the horizontal well Perform real-time measurements and regularly calibrate and maintain the sensors to ensure the accuracy and reliability of the measurement data; S12. Using advanced logging technology and core analysis methods, permeability data for each section of the horizontal well are obtained. The acquired data undergoes quality checks and preprocessing to remove outliers, providing a basis for subsequent calculations of permeability-related parameters. Appropriate statistical methods are then used to calculate the standard deviation of permeability. and average penetration rate ; S13. Collect fluid samples from the target section and adjacent sections of the horizontal well, and send them to a specialized laboratory. Use laboratory analysis methods to test the fluid samples from the target section and adjacent sections to obtain the accurate fluid viscosity of the target section. and the viscosity of the fluid in the adjacent section During the testing process, the experimental operating procedures were strictly followed to ensure the accuracy and repeatability of the test results. S14. Combining geological exploration data, reservoir numerical simulation, and actual production data, conduct a detailed analysis and evaluation of the distribution of interlayers in the reservoir. Taking into account factors such as interlayer thickness, permeability, and distribution range, comprehensively evaluate the distribution of interlayers in the reservoir and rationally determine the interlayer influence coefficient. ; S15. Accurately extract the injection-production ratio of horizontal wells from oil well production records (production database). Based on the reservoir's geological characteristics, fluid properties, development stage, and development experience of similar reservoirs, discussions were organized to scientifically determine a reasonable injection-production ratio. .

[0007] S2. Calculate the coefficient of variation of permeability, viscosity ratio, and injection-production ratio deviation coefficient; The formula for calculating the coefficient of variation of permeability is: In the formula: The coefficient of variation of permeability is dimensionless. The standard deviation of the permeability is expressed in units of 1000 kJ / m². ; Average penetration rate, in units of ; Based on the collected permeability data, the standard deviation of the permeability was calculated using statistical methods. and average penetration rate Then calculate the coefficient of variation of permeability. The coefficient of variation in permeability measures the degree of difference in permeability; the calculation results are reviewed and verified to ensure their accuracy and reasonableness. The formula for calculating the viscosity ratio is: In the formula: The viscosity ratio is dimensionless. Target fluid viscosity and the viscosity of the fluid in the adjacent section The maximum value in, in units of ; Target fluid viscosity and the viscosity of the fluid in the adjacent section The minimum value in, in units of ; The viscosity ratio between the target segment and the adjacent segment reflects the potential impact of fluid properties on inter-segment interference; during the calculation process, attention should be paid to the accuracy of the data and the retention of significant figures; The formula for calculating the injection-production ratio deviation coefficient is as follows: In the formula: The injection-production ratio deviation coefficient is dimensionless. The injection-production ratio for horizontal wells is dimensionless. For a reasonable injection-production ratio, dimensionless; The injection-production ratio deviation coefficient assesses the impact of the deviation of the injection-production ratio from the reasonable value on inter-segment interference; the calculation results are analyzed to determine the degree of deviation between the injection-production ratio and the reasonable value.

[0008] S3. Calculate the permeability difference correction coefficient, fluid viscosity difference correction coefficient, reservoir heterogeneity correction coefficient, and well pattern layout and production method correction coefficient by combining the coefficients determined by experiments or historical data. The formula for calculating the permeability difference correction coefficient is as follows: In the formula: This is a dimensionless correction coefficient for permeability differences. The coefficients are dimensionless and are determined in advance based on experimental or historical data fitting methods. The coefficient of variation of permeability is dimensionless. Sensitivity analysis was performed on the calculation results, and the evaluation coefficients were determined. The degree of influence on the correction factor; The formula for calculating the fluid viscosity difference correction factor is as follows: In the formula: This is a dimensionless correction factor for fluid viscosity differences. The coefficients are dimensionless and are determined in advance based on experimental or historical data fitting methods. The viscosity ratio is dimensionless. During the calculation process, the influence of different fluid properties on the correction coefficient is considered to ensure that the correction coefficient can accurately reflect the effect of fluid viscosity differences on inter-segment interference. The formula for calculating the reservoir heterogeneity correction factor is as follows: In the formula: This is a dimensionless correction factor for reservoir heterogeneity. The coefficients are dimensionless and are determined in advance based on experimental or historical data fitting methods. The coefficient is the interlayer influence coefficient, which is dimensionless. The coefficient is adjusted and optimized based on the geological characteristics of the reservoir and the actual production situation. The formula for calculating the correction coefficient for the well network layout and mining method is as follows: In the formula: This is a dimensionless correction factor for well network layout and mining method. The coefficients are dimensionless and are determined in advance based on experimental or historical data fitting methods. The injection-production ratio deviation coefficient is dimensionless. The coefficients should be adjusted reasonably according to the reservoir development strategy and production targets. The value of is such that the correction coefficient can accurately reflect the impact of the injection-production ratio deviation on inter-segment interference.

[0009] S4. Calculate the traditional inter-segment interference coefficient based on pressure difference; The formula for calculating the traditional inter-segment interference coefficient based on pressure difference is as follows: In the formula: The traditional inter-segment interference coefficient is based on pressure difference and is dimensionless. This represents the pressure difference between the target section and the adjacent section of the horizontal well, in MPa. The total pressure drop of the horizontal well is expressed in MPa. Error analysis is performed on the calculation results to assess the impact of measurement errors on traditional coefficients.

[0010] S5. Combine the comprehensive correction coefficient with the traditional inter-segment interference coefficient based on pressure difference to obtain the multi-factor inter-segment interference coefficient.

[0011] The formula for calculating the multi-factor inter-segment interference coefficient is as follows: In the formula: The inter-segment interference coefficient is a multi-factor interference coefficient, dimensionless. The traditional inter-segment interference coefficient is based on pressure difference and is dimensionless. This is a dimensionless correction coefficient for permeability differences. This is a dimensionless correction factor for fluid viscosity differences. This is a dimensionless correction factor for reservoir heterogeneity. This is a dimensionless correction coefficient for well network layout and mining method.

[0012] The calculation results are comprehensively analyzed and evaluated, and the degree and scope of inter-section interference are determined in combination with the actual situation of the reservoir.

[0013] The beneficial effects of this invention are: This invention provides a method for calculating the interference coefficient between horizontal well sections by comprehensively considering multiple factors, such as permeability differences, fluid properties, reservoir heterogeneity, well network layout, and production methods. This method enables accurate calculation of the interference coefficient between horizontal well sections, more precise assessment of interference between horizontal well sections, and provides a solid and reliable scientific basis for formulating scientific and reasonable production strategies during oilfield development. It effectively reduces inter-section interference, significantly improves reservoir recovery, and enhances the economic benefits of oilfield development. Attached Figure Description

[0014] Figure 1 This is a flowchart of the method of the present invention.

[0015] For those skilled in the art, other related figures can be obtained from the above figures without any creative effort. Detailed Implementation

[0016] To enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0017] Example 1 Oilfield A: The reservoirs in this oilfield are characterized by significant permeability variations and high fluid viscosity. Traditional methods for calculating inter-section interference coefficients based on pressure differentials have yielded unsatisfactory development strategies. Despite multiple injection-production adjustments, inter-section interference remains severe, resulting in slow well production growth and persistently high overall water cut.

[0018] like Figure 1 As shown, a method for calculating the interference coefficient between horizontal well sections by integrating multiple factors includes the following steps: S1. Collect basic data; Differential pressure data: , (Uses a high-precision pressure sensor with an error of ±0.1%) Penetration data: target segment Adjacent segments , , ; Fluid viscosity: (Target section heavy oil) (Adjacent section of thin oil) ; Interlayer influence coefficient: (Based on numerical simulation and core analysis); Note collection ratio data: Reasonable injection-production ratio , .

[0019] S2. Calculate the correction coefficients for permeability difference, fluid viscosity difference, reservoir heterogeneity, and well pattern layout and production method, based on the correction coefficients determined by experiments or historical data. =0.8 (experimental calibration), permeability difference correction factor ; =0.25, fluid viscosity difference correction factor =0.6, reservoir heterogeneity correction factor =0.4, Correction coefficient for well network layout and mining method S3. Calculate the traditional inter-segment interference coefficient based on pressure difference; S4. Combine the comprehensive correction coefficient with the traditional inter-segment interference coefficient based on pressure difference to obtain the multi-factor inter-segment interference coefficient; (Traditional methods underestimate by 3.7 times) The results show that, due to the combined effects of permeability differences and fluid viscosity, the inter-segment interference coefficient is much higher than that calculated by traditional methods.

[0020] S4. Improvement Measures and Effects Targeted plugging: Injecting nanosphere plugging agent into the high-permeability section (K=350 mD) achieves a plugging rate of >90%.

[0021] Injection-production optimization: The injection-production ratio was adjusted to 1.3, and the displacement efficiency in the low-permeability section was improved by 40%.

[0022] Results Comparison: Inter-well interference was significantly reduced, daily production increased by 25%, and overall water cut decreased by 7%, resulting in significant economic benefits.

[0023] Example 2 Oilfield B: This oilfield has numerous interlayers and exhibits strong heterogeneity (interlayer density reaches 3 layers / m). Traditional methods have failed to adequately consider the impact of interlayers on inter-section interference, resulting in ineffective development strategies to address this problem. Interference between wells occurs frequently, severely impacting production in some well sections.

[0024] A method for calculating the interference coefficient between horizontal well sections by integrating multiple factors includes the following steps: S1. Collect basic data; Differential pressure data: , ; Penetration data: , , ; Interlayer influence coefficient: (Mezzanine thickness > 2m, lateral extension > 500m); Note collection ratio data: Reasonable injection-production ratio , .

[0025] S2. Calculate the correction coefficients for permeability difference, fluid viscosity difference, reservoir heterogeneity, and well pattern layout and production method, based on the correction coefficients determined by experiments or historical data. =0.7, Permeability Difference Correction Factor ; =0.9, reservoir heterogeneity correction factor =0.5, Correction coefficient for well network layout and mining method S3. Calculate the traditional inter-segment interference coefficient based on pressure difference; S4. Combine the comprehensive correction coefficient with the traditional inter-segment interference coefficient based on pressure difference to obtain the multi-factor inter-segment interference coefficient; (Traditional methods underestimate by 4.1 times) The results show that, considering the influence of reservoir heterogeneity, the inter-section interference coefficient is much higher than that calculated by traditional methods.

[0026] S4. Improvement Measures and Effects Temporary plugging fracturing: Using fiber-based temporary plugging agents, new fractures are formed around the interlayer, increasing the fracture length by 35%.

[0027] Injection-production optimization: The injection-production ratio was adjusted to 1.8, and the pressure gradient in the low-permeability zone was increased by 22%.

[0028] After the measures were implemented, the oilfield's recovery rate increased by 4%, inter-section interference was effectively controlled, and the exploitation efficiency was significantly improved.

[0029] This invention comprehensively considers multiple key factors. Compared to a single calculation method based solely on pressure difference, it can more comprehensively and accurately capture the combined effects of various factors on inter-section interference in the actual reservoir environment, thereby significantly improving the accuracy of the inter-section interference coefficient calculation results. By providing high-precision calculation results, this invention helps to gain a deeper understanding of the actual situation of inter-section interference in horizontal wells, thereby formulating targeted and effective development strategies and providing strong support for scientific decision-making. This invention possesses high flexibility and wide adaptability. The coefficients a, b, c, and d in the formula can be flexibly adjusted according to the actual conditions such as the geological characteristics, fluid properties, and development stages of different reservoirs. This allows the method of this invention to adapt to various complex and changing reservoir environments, whether offshore or onshore, conventional or unconventional, accurately calculating the inter-section interference coefficient and providing effective technical support for the development of different types of reservoirs.

[0030] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A method for calculating the interference coefficient between horizontal well sections by integrating multiple factors, characterized in that: Includes the following steps: S1. Collect basic data; S2. Calculate the coefficient of variation of permeability, viscosity ratio, and injection-production ratio deviation coefficient; S3. Calculate the correction coefficients for permeability difference, fluid viscosity difference, reservoir heterogeneity, and well pattern layout and production method, based on the correction coefficients determined by experiments or historical data. S4. Calculate the traditional inter-segment interference coefficient based on pressure difference; S5. Combine the comprehensive correction coefficient with the traditional inter-segment interference coefficient based on pressure difference to obtain the multi-factor inter-segment interference coefficient.

2. The method for calculating the interference coefficient between horizontal well sections based on multiple factors as described in claim 1, characterized in that: The basic data includes the pressure difference between the target section and the adjacent section of the horizontal well, the total pressure drop of the horizontal well, the permeability, the fluid viscosity of the target section, the fluid viscosity of the adjacent section, the interlayer influence coefficient, and the injection-production ratio.

3. The method for calculating the interference coefficient between horizontal well sections based on multiple factors as described in claim 1, characterized in that: The formula for calculating the coefficient of variation of permeability is: In the formula: The coefficient of variation of permeability is dimensionless. The standard deviation of permeability is expressed in mD. The average permeability is expressed in mD.

4. The method for calculating the interference coefficient between horizontal well sections based on multiple factors as described in claim 1, characterized in that: The formula for calculating the viscosity ratio is: In the formula: The viscosity ratio is dimensionless. Target fluid viscosity and the viscosity of the fluid in the adjacent section The maximum value in, in units of ; Target fluid viscosity and the viscosity of the fluid in the adjacent section The minimum value in, in units of .

5. The method for calculating the interference coefficient between horizontal well sections based on multiple factors according to claim 1, characterized in that: The formula for calculating the injection-production ratio deviation coefficient is as follows: In the formula: The injection-production ratio deviation coefficient is dimensionless. The injection-production ratio for horizontal wells is dimensionless. For a reasonable injection-production ratio, dimensionless.

6. The method for calculating the interference coefficient between horizontal well sections based on multiple factors according to claim 1, characterized in that: The formula for calculating the permeability difference correction coefficient is as follows: In the formula: This is a dimensionless correction coefficient for permeability differences. The correction coefficients are dimensionless and are determined in advance based on experimental or historical data fitting methods. The coefficient of variation of permeability is dimensionless. The formula for calculating the fluid viscosity difference correction factor is as follows: In the formula: This is a dimensionless correction factor for fluid viscosity differences. The correction coefficients are dimensionless and are determined in advance based on experimental or historical data fitting methods. The viscosity ratio is dimensionless. The formula for calculating the reservoir heterogeneity correction factor is as follows: In the formula: This is a dimensionless correction factor for reservoir heterogeneity. The correction coefficients are dimensionless and are determined in advance based on experimental or historical data fitting methods. The interlayer influence coefficient is dimensionless. The formula for calculating the correction coefficient for the well network layout and mining method is as follows: In the formula: This is a dimensionless correction factor for well network layout and mining method. The correction coefficients are dimensionless and are determined in advance based on experimental or historical data fitting methods. This is the injection-production ratio deviation coefficient, which is dimensionless.

7. The method for calculating the interference coefficient between horizontal well sections based on multiple factors according to claim 1, characterized in that: The formula for calculating the traditional inter-segment interference coefficient based on pressure difference is as follows: In the formula: The traditional inter-segment interference coefficient is based on pressure difference and is dimensionless. This represents the pressure difference between the target section and the adjacent section of the horizontal well, in MPa. This represents the total pressure drop of the horizontal well, expressed in MPa.

8. The method for calculating the interference coefficient between horizontal well sections based on multiple factors according to claim 1, characterized in that: The formula for calculating the multi-factor inter-segment interference coefficient is as follows: In the formula: The inter-segment interference coefficient is a multi-factor interference coefficient, dimensionless. The traditional inter-segment interference coefficient is based on pressure difference and is dimensionless. This is a dimensionless correction coefficient for permeability differences. This is a dimensionless correction factor for fluid viscosity differences. This is a dimensionless correction factor for reservoir heterogeneity. This is a dimensionless correction coefficient for well network layout and mining method.

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