CN-121997800-A - Deep shale gas production system optimization method based on multistage split optimization strategy

CN121997800ACN 121997800 ACN121997800 ACN 121997800ACN-121997800-A

Abstract

The invention discloses a deep shale gas production system optimization method based on a multistage split optimization strategy, which comprises the steps of S1, collecting and arranging target block geological parameters and engineering parameters, S2, establishing a deep shale gas reservoir numerical simulation model according to the basic parameters, correcting the numerical simulation model by using historical production data, S3, constructing a production system optimization objective function, wherein constraint conditions in the objective function include daily gas production threshold values, and optimization variables are bottom hole flow pressure, S4, solving a shale gas production system mathematical model through a coupling optimization algorithm and an oil reservoir numerical simulator to obtain a first generation regulated optimal production system, S5, generating a next generation regulated optimal production system by using the multistage split optimization strategy based on the first generation regulated optimal production system, and carrying out dynamic regulation optimization of full life cycle production systems. The invention adopts a multistage split optimization strategy, and provides a scientific and efficient optimization method for optimizing the shale gas production system.

Inventors

XU SHIQIAN
LIANG YAOJUN
ZHOU WENJIAN
GUO JIANCHUN
LIU YUXUAN
REN WENXI
XUE QINRU
Sa Yingpeng
ZHANG SHIJIA
YU WEN

Assignees

西南石油大学

Dates

Publication Date: 20260508
Application Date: 20251223

Claims (10)

1. The deep shale gas production system optimization method based on the multistage split optimization strategy is characterized by comprising the following steps of: s1, collecting basic parameters of a target block, wherein the basic parameters comprise geological parameters and engineering parameters; S2, establishing a deep shale gas reservoir numerical simulation model according to the basic parameters, and correcting the numerical simulation model by using historical production data; s3, constructing a production system optimization objective function, wherein constraint conditions in the objective function comprise a daily gas yield threshold, and an optimization variable is bottom hole flow pressure; s4, solving a shale gas production system mathematical model through a coupling optimization algorithm and an oil reservoir numerical simulator to obtain a first-generation regulated optimal production system; And S5, generating the optimal production system of the next generation of regulation and control by utilizing a multi-stage split optimization strategy based on the optimal production system of the first generation of regulation and control, and developing dynamic regulation and control optimization of the full life cycle production system.
2. The shale gas production system optimization method according to claim 1, wherein the step S2 comprises: s201, establishing a shale gas reservoir numerical simulation model based on a gas reservoir numerical simulation method; S202, in the numerical simulation model, using a crack parameter as input and using a bottom hole pressure as output, fitting the bottom hole pressure distribution and the numerical value in historical production data, and correcting the numerical simulation model.
3. The shale gas production system optimization method according to claim 1, wherein the step S3 comprises: s301, taking the maximized cumulative gas yield as an optimization target in a production system optimization objective function; s302, establishing variable conditions for optimizing a shale gas production system; s303, constructing constraint conditions in an objective function: q g ≥C Where q g denotes daily gas production, C is a constant, p i is a bottom hole pressure at a certain point, p min is an allowable bottom hole pressure minimum, and p max is an allowable bottom hole pressure maximum.
4. The shale gas production system optimization method according to claim 1, wherein the step S4 comprises: s401, generating a bottom hole flow pressure corresponding to an optimal production system regulated and controlled once; S402, calculating corresponding production dynamic parameters by utilizing a numerical simulation model based on the bottom hole flow pressure; S403, inputting the bottom hole flow pressure and the corresponding production dynamic parameters into an intelligent optimization algorithm, starting optimizing by the intelligent optimization algorithm, generating a next generation simulation scheme, and repeating the steps S402 and S403 until the iterative optimizing process meets the convergence condition.
5. The method according to claim 4, wherein the step S401 is to generate a bottom hole stream pressure by using latin hypercube sampling.
6. The method according to claim 4, wherein the dynamic production parameters in step S402 include daily gas production, cumulative gas production, daily water production, and cumulative water production.
7. The shale gas production system optimization method according to claim 1, wherein the step S5 comprises: S501, based on the one-time regulated optimal production system scheme obtained in the step S4, dividing the total time step of the first time into two parts according to a multi-stage split optimization method by taking the result obtained in the step S4 as an initial value, and optimizing the production system again to obtain production dynamics corresponding to different bottom hole flow pressure schemes; S502, inputting production dynamics corresponding to different bottom hole flow pressure schemes into an intelligent optimization algorithm, starting optimizing by the intelligent optimization algorithm according to a self optimizing mechanism, generating a next generation simulation scheme, and repeating the steps S402 and S403 until the iterative optimizing process meets convergence conditions; s503, taking the simulation scheme generated in the step S502 as an initial value, repeating the step S502 until the accumulated gas yield of the optimized production scheme reaches the maximum value, and outputting the bottom hole stream pressure distribution state and the numerical value of the full life cycle, namely the optimal production system of the full life cycle.
8. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, the processor implementing the shale gas production regime optimization method of any of claims 1-7 when the program is executed.
9. A storage medium storing computer-executable instructions for performing the shale gas production regime optimization method of any of claims 1-7 when executed by a computer processor.
10. A computer program product comprising a computer program which when executed by a processor implements the shale gas production regime optimization method of any of claims 1-7.

Description

Deep shale gas production system optimization method based on multistage split optimization strategy Technical Field The invention relates to the technical field of petroleum and natural gas engineering, in particular to a deep shale gas production system optimization method based on a multistage split optimization strategy. Background The shale gas resources in China are rich, wherein the recoverable resources of the deep-ultra-deep shale gas technology account for 56.63% of the total reserve, so that huge development potential is shown, and the scientific and effective development of the deep shale gas has extremely important significance for guaranteeing the national energy safety. In the deep shale gas development process, if the well bottom flow pressure drops too fast, although higher yield can be obtained in the early stage, the dynamic closure of cracks is serious, the subsequent productivity is insufficient, the finally obtained cumulative gas yield is possibly not high, and the yield of the shale gas can be improved by optimizing the shale gas production system. The invention patent with the application number 202310058008.2 proposes a multistage fracturing horizontal well production grading optimization and effect prediction method, which divides a multistage fracturing horizontal well into a plurality of different production sections, performs production system optimization by carrying out fine production simulation on each section, and can be used for production optimization on the fracturing horizontal well in the research area. When the method is used for optimizing the production system, the production schemes are required to be compared manually, and then the production parameters are optimized, so that the required time and the cost are high. In addition, when each optimization segment is independently simulated, the optimization variables are more, the optimization process is complex, the optimization method only optimizes the control scheme of the initial bottom hole flow pressure, the full life cycle dynamic regulation is not adopted, the obtained result is limited to the comparison between schemes to obtain the optimal value, and the optimization effect can be changed along with the production time, so that the method has the advantages that the required time cost is high, the obtained solution scheme is not the global optimal solution, and the optimal development effect and economic benefit cannot be ensured. The invention patent with the application number 202310058351.7 provides an optimal design method for the production choke working system of a multistage fracturing horizontal well, and the method also divides a reservoir produced by the horizontal well into a plurality of independent simulation units to optimize the production system, divides the optimized time steps, and can be used for optimizing the production of the fracturing horizontal well in the research area. When the method is used for optimizing the production system, the production schemes are also required to be compared manually, and the required time and the cost are high when the production parameters are optimized. Secondly, the time step is divided, but the time step is divided only for simulating the development condition of the variable bottom hole flow pressure, not for optimizing the production system, not for dynamically regulating and controlling the full life cycle of the bottom hole flow pressure, still facing the conditions of more optimization variables and complex optimization process when optimizing, and the obtained optimal scheme is not necessarily a global optimal solution, so that the optimal development effect and economic benefit cannot be ensured. How to efficiently optimize the shale gas production system based on the full life cycle becomes a technical problem to be solved. Disclosure of Invention The invention aims to provide a rapid optimization method of a shale production system based on a full life cycle, in particular to a deep shale gas production system optimization method based on a multistage split optimization strategy, which comprises the following steps: s1, collecting basic parameters of a target block, wherein the basic parameters comprise geological parameters and engineering parameters; S2, establishing a deep shale gas reservoir numerical simulation model according to the basic parameters, and correcting the numerical simulation model by using historical production data; s3, constructing a production system optimization objective function, wherein constraint conditions in the objective function comprise a daily gas yield threshold, and an optimization variable is bottom hole flow pressure; s4, solving a shale gas production system mathematical model through a coupling optimization algorithm and an oil reservoir numerical simulator to obtain a first-generation regulated optimal production system; And S5, generating the optimal production system of the next generation of reg