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CN-121997793-A - Method, system, equipment and medium for calculating water invasion amount of fracture-controlled fracture-cavity carbonate reservoir

CN121997793ACN 121997793 ACN121997793 ACN 121997793ACN-121997793-A

Abstract

The method, the system, the equipment and the medium for calculating the water invasion amount of the fracture-controlled fracture-cavity carbonate reservoir comprise the steps of 1, calculating to obtain the theoretical liquid production amount driven by external water after water invasion according to the obtained oil well production volume in the stable production stage before water invasion, the stratum pressure in the stable production stage before water invasion and the production volume after water invasion, 2, calculating to obtain the water volume of stratum pressure change caused by water invasion according to the obtained actual stratum pressure after water invasion, and 3, calculating to obtain the water invasion amount after water invasion according to the obtained theoretical liquid production amount driven by external water after water invasion and the water volume of stratum pressure change caused by water invasion.

Inventors

  • LIANG RUIHAN
  • YUAN XIAOMAN
  • ZHANG JIE
  • LIU ZIWEI
  • Yi Lixiatikudi
  • KONG YUANYUAN
  • SHI TAO

Assignees

  • 中国石油天然气股份有限公司

Dates

Publication Date
20260508
Application Date
20241108

Claims (10)

  1. 1. A method for calculating the water invasion amount of a fracture-controlled fracture-cave carbonate reservoir, comprising the steps of: Step 1, calculating to obtain theoretical liquid production driven by external water after water invasion according to the obtained oil well production volume in the stable production stage before water invasion, stratum pressure during water invasion and production volume after water invasion; Step2, calculating to obtain the water volume of formation pressure change caused by water invasion according to the obtained actual formation pressure after water invasion; And step 3, calculating to obtain the water invasion amount of the fracture-controlled fracture-cavity carbonate reservoir after water invasion according to the obtained theoretical liquid production amount driven by the external water body after water invasion and the water body volume of stratum pressure change caused by water invasion.
  2. 2. The method for calculating the water invasion amount of the fracture-controlled fracture-cavity type carbonate reservoir according to claim 1, wherein in the step 1, the theoretical liquid yield driven by the external water body after water invasion is calculated, and the specific method is as follows: s11, calculating to obtain the unit pressure drop liquid yield before water invasion according to the obtained oil well yield volume in the stable production stage before water invasion, the stratum pressure in the stable production stage before water invasion and the stratum pressure during water invasion; S12, calculating to obtain the theoretical liquid yield driven by the original elastic energy after water invasion according to the obtained liquid yield per unit pressure drop before water invasion; S13, calculating to obtain the theoretical liquid yield driven by the external water body after water invasion according to the obtained theoretical liquid yield driven by the original elastic energy after water invasion and the obtained output volume after water invasion.
  3. 3. The method for calculating the water invasion amount of the fracture-controlled fracture-cavity type carbonate reservoir according to claim 2, wherein in S12, the theoretical liquid yield driven by the original elastic energy after water invasion is calculated, and the specific method is as follows: Acquiring stratum pressure obtained by converting according to the original production trend under the condition that water invasion does not occur; And calculating the theoretical liquid production amount driven by the original elastic energy after water invasion by combining the formation pressure obtained by converting according to the original production trend under the condition that water invasion does not occur and the unit pressure drop liquid production amount before water invasion.
  4. 4. A method for calculating the water invasion amount of a fracture-controlled fracture-cave carbonate reservoir according to claim 3, wherein the formation pressure obtained by converting the primary production trend without water invasion is obtained by the following specific method: Drawing a graph between formation pressure and cumulative liquid volume; Extending a straight line P 1 P 2 between the formation pressure P 1 at the pre-water-invasion stable production stage and the formation pressure P 2 at the water invasion on the coordinate graph to obtain a trend line of the straight line P 1 P 2 ; and (3) bringing the accumulated liquid volume corresponding to the actual stratum pressure P 4 after water invasion into the trend line to obtain the stratum pressure obtained by converting according to the original production trend under the condition that water invasion does not occur.
  5. 5. The method for calculating the water invasion amount of the fracture-controlled fracture-cavity carbonate reservoir according to claim 2, wherein in S13, the theoretical liquid production amount driven by the external water body after water invasion is calculated according to the following formula: Q 2 ＝N 2 -Q 1 Wherein N 2 is the output volume of the target oil well after water invasion, Q 2 is the theoretical liquid yield driven by external water after water invasion, and Q 1 is the theoretical liquid yield driven by original elastic energy after water invasion.
  6. 6. The method for calculating the water invasion amount of a fracture-controlled fracture-cave type carbonate reservoir according to claim 1, wherein in the step 2, the water volume of the formation pressure change caused after the water invasion is calculated according to the following formula: W=J*(P 4 -P 3 ) wherein P 4 is the actual formation pressure after water invasion, W is the water volume of formation pressure change caused by water invasion, J is the unit pressure drop liquid production amount before water invasion, and P3 is the formation pressure obtained by converting according to the original production trend under the condition that water invasion does not occur.
  7. 7. A system for calculating a fracture-controlled fracture-cave carbonate reservoir water invasion amount, comprising: The post-water-invasion theoretical liquid yield calculation unit is used for calculating and obtaining the theoretical liquid yield driven by the external water body after water invasion according to the obtained oil well output volume in the pre-water-invasion stable production stage, the stratum pressure during water invasion and the output volume of the post-water-invasion fracture-cavity-control carbonate reservoir; The post-water-invasion water body volume calculation unit is used for calculating the water body volume of formation pressure change caused by water invasion according to the obtained actual formation pressure after water invasion; The water invasion amount calculation unit is used for calculating the water invasion amount of the fracture-controlled cavity type carbonate reservoir after water invasion according to the theoretical liquid yield driven by the external water body after water invasion and the water volume of formation pressure change caused by water invasion.
  8. 8. A computer device, comprising: A processor adapted to execute a computer program; A computer readable storage medium having stored therein a computer program which, when executed by the processor, performs the method of any of claims 1 to 6.
  9. 9. A computer readable storage medium storing a computer program, characterized in that the computer program when executed by a processor implements the method according to any one of claims 1 to 6.
  10. 10. A computer program product, characterized in that the computer program product comprises a computer program which, when executed by a processor, implements the method according to any of claims 1 to 6.

Description

Method, system, equipment and medium for calculating water invasion amount of fracture-controlled fracture-cavity carbonate reservoir Technical Field The invention belongs to the field of oilfield development, and particularly relates to a method, a system, equipment and a medium for calculating water invasion amount of a fracture-controlled fracture-cavity carbonate reservoir. Background At present, the fracture-controlled fracture-cavity type carbonate reservoir generally faces the problem of bottom water coning, the yield of oil well bottom water is reduced by more than 80% after breakthrough, the development order is seriously affected, and the treatment strategy for the fracture-controlled fracture-cavity type carbonate reservoir bottom water coning at present comprises the following steps: First, adjusting production parameters Reducing the production pressure difference by reducing the wellhead pressure or increasing the pressure of the reservoir or formation, reducing the formation of water coning. And (3) adjusting the oil extraction speed, namely slowing down the oil extraction speed and slowing down the formation speed of the water cone. Second, the downhole operation is adjusted Plugging the crack, namely plugging the crack at the bottom of the well by using a plugging agent or cement slurry to prevent water from penetrating. Adjusting the bottom hole structure, namely reducing the formation of water cone by adjusting the bottom hole structure, such as adding a sand control layer or adjusting the bottom hole angle. Third, chemical treatment The use of chemical agents, such as polymers, cross-linking agents, etc., improves the permeability of the oil or gas reservoir and reduces the formation of water coning. At present, whether a control strategy of the bottom water coning of the fracture-control cave type carbonate reservoir is effective or not is judged, the water invasion amount needs to be calculated, and how to accurately calculate the water invasion amount is a great difficulty in the bottom water coning treatment, so that the water invasion amount is accurately calculated, and the study of the bottom water coning treatment of the fracture-control cave type carbonate reservoir is worth guiding. The current methods for calculating the water invasion amount are various, but each method has certain defects and limitations, such as: First, volumetric method This method relies on accurate geologic data such as reservoir geometry, porosity, permeability, etc., which in practice often have uncertainties that lead to inaccurate results. Second, pressure drop method This method requires continuous downhole pressure monitoring data, but in practice the monitoring data may be discontinuous or subject to errors or wellbore effects (e.g., wellbore storage effects) resulting in inaccurate calculations. Thirdly, yield method The production monitoring data may be affected by a variety of factors, such as downhole equipment failure, operational errors, etc., resulting in inaccurate production data, and the method does not take into account dynamic changes in the reservoir, such as gradual decreases in reservoir pressure, which may result in higher computational results. Fourth, numerical simulation method The numerical simulation method needs to build a complex oil reservoir model, which not only needs a great deal of time and calculation resources, but also needs a user to have higher expertise, so that the calculation cost is high. Disclosure of Invention The invention aims to provide a method, a system, equipment and a medium for calculating the water invasion amount of a fracture-controlled fracture-cavity carbonate reservoir, which solve the defect of inaccurate calculation result of the existing water invasion amount calculation method. In order to achieve the above purpose, the invention adopts the following technical scheme: The invention provides a method for calculating the water invasion amount of a fracture-controlled fracture-cavity carbonate reservoir, which comprises the following steps: Step 1, after the bottom water coning of a fracture-controlled fracture-cavity carbonate reservoir is prevented, calculating to obtain the theoretical liquid production driven by an external water body after water invasion according to the obtained oil well output volume in the stable production stage before water invasion, the stratum pressure during water invasion and the output volume after water invasion; Step2, calculating to obtain the water volume of formation pressure change caused by water invasion according to the obtained actual formation pressure after water invasion; step 3, calculating to obtain the water invasion amount of the fracture-controlled fracture-cavity carbonate reservoir after water invasion according to the obtained theoretical liquid production amount driven by the external water body after water invasion and the water body volume of stratum pressure change caused by water invasio