CN-121993130-A - Yield increasing method for water plugging of bottom water reservoir vertical well

CN121993130ACN 121993130 ACN121993130 ACN 121993130ACN-121993130-A

Abstract

The application discloses a yield increasing method for water plugging of a bottom water reservoir vertical well, and relates to the technical field of oil and gas exploitation. The method for increasing the water plugging yield of the vertical well of the bottom water reservoir comprises the following steps of analyzing the water flooding characteristics of a target vertical well, determining the water flooding characteristics of the bottom water reservoir as a target measure well, conducting high-strength deep water plugging on the target measure well to plug a bottom water coning channel, laterally windowing the top of the target measure well to form at least one horizontal side well, and communicating a top residual oil enrichment area or an inter-well residual oil enrichment area of the target measure well by the horizontal side well.

Inventors

LIU YUJIAN
SUN ZHONGJIE
WANG YAGUANG
LIN XIAOHAI
Shan Ziqi

Assignees

长江大学
安东石油技术（集团）有限公司

Dates

Publication Date: 20260508
Application Date: 20260213

Claims (10)

1. The production increasing method for the water plugging of the bottom water reservoir vertical well is characterized by comprising the following steps of: analyzing the flooding characteristics of the target vertical well, and determining the flooding characteristics of the bottom water reservoir as a target measure well; Performing high-strength deep water shutoff on the target measure well to block a bottom water coning channel; And laterally windowing the top of the target measure well to form at least one horizontal side well, wherein the horizontal side well is communicated with a top residual oil enrichment zone or an interwell residual oil enrichment zone of the target measure well.
2. The stimulation method for bottom-water reservoir vertical well plugging as recited in claim 1, wherein said step of plugging the bottom-water coning channel by high-strength deep plugging of said target measure well comprises: Determining the type of the high-strength water shutoff agent according to the physical characteristics of the stratum where the target measure well is located; Determining the communication depth between the target measure well and the production layer according to the well completion type of the target measure well and calculating the dosage of the high-strength water shutoff agent; and injecting a high-strength water shutoff agent to block water.
3. The stimulation method for vertical well water shutoff of a bottom-water reservoir as recited in claim 2, wherein said step of determining the type of high-strength water shutoff agent based on the physical characteristics of the reservoir in which said target measure well is located comprises: And the high-strength water shutoff agent comprises at least one of a high-strength inorganic gel water shutoff agent, a high-strength monomer underground polymerization gel water shutoff agent and a high-strength low-density water shutoff agent corresponding to the physical property characteristics of the oil reservoir where the target measure well is located.
4. The stimulation method for vertical well water shutoff of bottom-water reservoirs of claim 3, wherein the high-strength water shutoff agent comprises at least one of a high-strength inorganic gel shutoff agent, a high-strength monomer underground polymerized gel shutoff agent and a high-strength low-density shutoff agent corresponding to physical characteristics of a reservoir where the target measure well is located, and comprises: The oil reservoir where the target measure well is located is a low-permeability porous bottom layer, and the high-strength water shutoff agent comprises a high-strength inorganic gel water shutoff agent; The oil reservoir where the target measure well is located is a porosity or microcrack development stratum with medium-high stratum permeability, and the high-strength water shutoff agent comprises a high-strength monomer underground polymerized gel water shutoff agent; the oil reservoir where the target measure well is located is a stratum with severe crack hole development and leakage, and the high-strength water shutoff agent comprises a high-strength low-density water shutoff agent.
5. The stimulation method for vertical well water shutoff of a bottom-water reservoir of claim 2, wherein the step of determining the communicable depth of the target measure well and the producing zone and calculating the usage of the high-strength water shutoff agent based on the completion type of the target measure well comprises: Calculating the dosage of the high-strength water shutoff agent according to the following formula (1) Wherein: the dosage of the high-strength water shutoff agent is that of the high-strength water shutoff agent; the radius of a shaft of a measure well for a target, m; The communication depth m of the target measure well and the production layer is the communication depth m; average porosity of the stratum where the target measure well is located; and (3) carrying out factors for large pore canals of the stratum where the target measure well is located.
6. The stimulation method for vertical well water shutoff of a bottom-water reservoir of claim 2, wherein the step of determining the communicable depth of the target measure well and the producing zone and calculating the usage of the high-strength water shutoff agent based on the completion type of the target measure well comprises: And in the case of open hole completion, the communication depth of the target measure well and the production layer is the distance between the initial depth of the open hole section of the target measure well and the initial depth of the sand surface.
7. The stimulation method for vertical well water shutoff of a bottom-water reservoir of claim 2, wherein the step of determining the communicable depth of the target measure well and the producing zone and calculating the usage of the high-strength water shutoff agent based on the completion type of the target measure well comprises: the target measure well is in the case of perforation completion, and the communication depth between the target measure well and the production layer is perforation section depth.
8. The stimulation method for bottom-water reservoir vertical well plugging of claim 1, wherein the step of laterally windowing the top of the target measure well to form at least one horizontal side well, the horizontal side well communicating with a top residual oil rich zone or an interwell residual oil rich zone of the target measure well, comprises: Determining a sidetracking direction; determining a sidetracking height; determining the number of sidetracking points; And laterally windowing the top of the target measure well to form at least one horizontal side well.
9. The stimulation method for vertical well plugging of a bottom-water reservoir of claim 8, wherein said step of determining a sidetrack direction comprises: determining the position of a water-oil interface according to the oil reservoir structure of the stratum where the target measure well is located; and determining the sidetracking direction according to the water-oil interface position, the target measure well and the distribution of the surrounding wells.
10. The stimulation method for vertical well plugging of a bottom-water reservoir of claim 8, wherein the step of determining the sidetrack height comprises: determining the height of a gas layer or a cover layer according to the oil reservoir structure of the stratum where the target measure well is located; Determining the sidetracking height according to the height of the gas layer or the cover layer; wherein the sidetrack height is located between the gas layer or cap layer and the water-oil interface and near the gas layer or cap layer.

Description

Yield increasing method for water plugging of bottom water reservoir vertical well Technical Field The application relates to the technical field of oil and gas reservoir exploitation, in particular to a yield increasing method for water plugging of a bottom water reservoir vertical well. Background The bottom water oil reservoir is a common oil reservoir type and is characterized in that the lower part of an oil reservoir is directly connected with a wide water-bearing zone, in the vertical well exploitation process, the bottom pressure is lower than the oil reservoir pressure, a pressure drop funnel is formed, and due to the oil-water density difference, the water phase is easier to push upwards, and a conical oil-water interface bulge, namely a water cone bottom water coning phenomenon, is formed below the bottom of the well. Bottom water coning can lead to premature water breakthrough in the well, severely affecting the bottom water reservoir crude oil yield and final recovery. Thus, there is a need for stimulation operations for bottom water reservoirs using water shutoff techniques. Currently, more sophisticated water shutoff methods include mechanical and chemical water shutoff. However, mechanical water shutoff is mainly aimed at reservoirs with interlayer, and is ineffective for bottom water reservoirs, chemical water shutoff can be applicable only to wells with increased water-avoiding height space or has engineering risk of causing blocking injury to upper reservoirs, namely, the yield of the bottom water reservoirs cannot be increased effectively by the existing mature water shutoff method. Disclosure of Invention The embodiment of the invention provides a yield increasing method for plugging water in a bottom water reservoir vertical well, which aims to solve the problem that the yield increasing cannot be realized by plugging bottom water coning in the vertical well in the prior art. In order to solve the technical problems, the embodiment of the application provides the following technical scheme: The application provides a yield increasing method for water plugging of a bottom water reservoir vertical well, which comprises the following steps: analyzing the flooding characteristics of the target vertical well, and determining the flooding characteristics of the bottom water reservoir as a target measure well; Performing high-strength deep water shutoff on the target measure well to block a bottom water coning channel; And laterally windowing the top of the target measure well to form at least one horizontal side well, wherein the horizontal side well is communicated with a top residual oil enrichment zone or an interwell residual oil enrichment zone of the target measure well. In some modified embodiments of the present application, the step of performing high-strength deep water shutoff on the target measure well to plug the bottom water coning channel includes: Determining the type of the high-strength water shutoff agent according to the physical characteristics of the stratum where the target measure well is located; Determining the communication depth between the target measure well and the production layer according to the well completion type of the target measure well and calculating the dosage of the high-strength water shutoff agent; and injecting a high-strength water shutoff agent to block water. In some modified embodiments of the present application, the step of determining the type of the high-strength water shutoff agent according to the physical characteristics of the reservoir where the target measure well is located includes: And the high-strength water shutoff agent comprises at least one of a high-strength inorganic gel water shutoff agent, a high-strength monomer underground polymerization gel water shutoff agent and a high-strength low-density water shutoff agent corresponding to the physical property characteristics of the oil reservoir where the target measure well is located. In some modified embodiments of the present application, the aforementioned physical property characteristics of the reservoir where the target measure well is located correspond to the physical property characteristics of the reservoir where the target measure well is located, and the high-strength water shutoff agent includes at least one of a high-strength inorganic gel water shutoff agent, a high-strength monomer underground polymerized gel water shutoff agent, and a high-strength low-density water shutoff agent, including: The oil reservoir where the target measure well is located is a low-permeability porous bottom layer, and the high-strength water shutoff agent comprises a high-strength inorganic gel water shutoff agent; The oil reservoir where the target measure well is located is a porosity or microcrack development stratum with medium-high stratum permeability, and the high-strength water shutoff agent comprises a high-strength monomer underground polymerized gel water shutoff agent;