CN-119801530-B - Shale oil recovery method

CN119801530BCN 119801530 BCN119801530 BCN 119801530BCN-119801530-B

Abstract

The application discloses a shale oil recovery method, and relates to the technical field of oil and gas reservoir development. The method comprises the steps of aiming at a shale oil reservoir, deploying a development well pattern, fracturing the shale oil reservoir through the development well pattern to enable the at least two wells to be communicated with each other, injecting fluid media into the shale oil reservoir through the development well pattern, and recovering the shale oil reservoir after the fluid media are injected through the development well pattern. According to the method, large-scale shale oil recovery is realized through the communicated development well pattern in a fluid medium imbibition displacement mode, and the total recovery ratio of the shale oil reservoir is improved.

Inventors

WANG HAIFENG
ZHANG YIJING
WANG XIAOYAN
ZHANG SHAOZHE
ZHANG YANG
JIANG WENYA
MA ZHONGMEI
ZHANG XUDONG
ZHANG NAN
LI JIANBING

Assignees

中国石油天然气股份有限公司

Dates

Publication Date: 20260512
Application Date: 20231010

Claims (6)

1. A shale oil recovery method, the method comprising: Deploying a development well pattern for a shale oil reservoir, the development well pattern comprising at least two wells; Fracturing the shale oil reservoir through the development well pattern so that the at least two wells are communicated with each other through a crack between the wells; performing well closing treatment for the development well pattern for a first set time period; Recovering the shale oil reservoir after fracturing through the development well pattern; injecting a fluid medium into the shale oil reservoir at a first rate through an injection well of the at least two wells; Closing the remaining wells, in case the fluid medium is obtained through the remaining wells of the at least two wells, except the injection well; Injecting a fluid medium into the shale oil reservoir through the injection well with each of the remaining wells closed, the second rate being greater than the first rate; Closing the injection well after a first set amount of fluid medium is injected into the shale oil reservoir through the injection well; and (3) recovering the shale oil reservoir after the fluid medium is injected through the development well pattern.
2. The method of claim 1, wherein the fluid medium comprises at least one of a gaseous medium, a liquid medium, and a gas-liquid composite medium.
3. The method according to claim 1, wherein the method further comprises: And when the recovery efficiency of recovering the fractured shale oil reservoir is lower than a first threshold value, starting from the injection well passing through the at least two wells, and injecting the fluid medium into the shale oil reservoir at a first speed.
4. The method of claim 1, wherein after the closing the injection well, further comprising: And performing well-closing treatment on the development well pattern for a second set time period, wherein the second set time period is related to the type of the fluid medium.
5. The method of claim 4, wherein in the event that the at least two wells are at least two horizontal wells, the method further comprises: determining a well opening sequence according to the type of the fluid medium and the high and low positions of the at least two horizontal wells; and sequentially starting the at least two horizontal wells according to the well starting sequence.
6. The method according to claim 1, wherein the method further comprises: And when the recovery efficiency of the shale oil reservoir after the fluid medium is injected is lower than a second threshold value, changing injection wells in the development well pattern and/or changing the type of the fluid medium.

Description

Shale oil recovery method Technical Field The embodiment of the application relates to the technical field of oil and gas reservoir development, in particular to a shale oil recovery method. Background With the development of old oil fields entering the middle and later stages, the efficiency improvement and the production stability pressure are increasingly increased, and shale oil reservoirs gradually enter the category of exploration and development in order to improve the oil gas development level. At present, the problem that shale oil reservoirs are compact and difficult to mine is solved. Shale oil development has been largely through the way of single well volumetric fracturing, creating a complex network of slots in the shale oil reservoir that extend around the wellbore, thereby establishing oil flow passages. However, the above methods are based on single well development of shale oil recovery, and it is difficult to improve the total recovery of shale oil reservoirs from a scale application perspective. Disclosure of Invention The embodiment of the application provides a shale oil recovery method. The technical scheme provided by the embodiment of the application is as follows: according to one aspect of an embodiment of the present application, there is provided a shale oil recovery method, the method comprising: Deploying a development well pattern for a shale oil reservoir, the development well pattern comprising at least two wells; Fracturing the shale oil reservoir through the development well pattern so that the at least two wells are in communication with each other; injecting a fluid medium into the shale oil reservoir through the development well pattern; and (3) recovering the shale oil reservoir after the fluid medium is injected through the development well pattern. In some embodiments, the fluid medium comprises at least one of a gaseous medium, a liquid medium, a gas-liquid composite medium. In some embodiments, where the at least two wells are at least two horizontal wells, the injecting fluid medium into the shale oil reservoir through the development pattern comprises: injecting a gaseous medium into the shale oil reservoir through a high-level well of the at least two horizontal wells; And/or the number of the groups of groups, Injecting a liquid medium into the shale oil reservoir through a lower well of the at least two horizontal wells. In some embodiments, the injecting a fluid medium into the shale oil reservoir through the development well pattern comprises: determining an injection well from the at least two wells according to the reservoir distribution of the shale oil reservoir; and alternately injecting a gas medium and a liquid medium into the shale oil reservoir through the injection well. In some embodiments, after fracturing the shale oil reservoir through the development pattern such that the at least two wells are in communication with each other, further comprising: performing well closing treatment for the development well pattern for a first set time period; and (3) recovering the shale oil reservoir after fracturing through the development well pattern. In some embodiments, the injecting a fluid medium into the shale oil reservoir through the development well pattern comprises: And under the condition that the recovery efficiency of recovering the shale oil reservoir after fracturing is lower than a first threshold value, injecting the fluid medium into the shale oil reservoir through the development well pattern. In some embodiments, the injecting a fluid medium into the shale oil reservoir through the development well pattern comprises: injecting a fluid medium into the shale oil reservoir at a first rate through an injection well of the at least two wells; Closing the remaining wells, in case the fluid medium is obtained through the remaining wells of the at least two wells, except the injection well; Injecting a fluid medium into the shale oil reservoir through the injection well with each of the remaining wells closed, the second rate being greater than the first rate; after a first set amount of fluid medium is injected into the shale oil reservoir through the injection well, the injection well is closed. In some embodiments, after injecting the fluid medium into the shale oil reservoir through the development well pattern, further comprising: And performing well-closing treatment on the development well pattern for a second set time period, wherein the second set time period is related to the type of the fluid medium. In some embodiments, in the event that the at least two wells are at least two horizontal wells, the method further comprises: determining a well opening sequence according to the type of the fluid medium and the high and low positions of the at least two horizontal wells; and sequentially starting the at least two horizontal wells according to the well starting sequence. In some embodiments, the method further comprises: And when the re