Study on Production Optimization Method of Fractured Reservoir Based on Connectivity Model

Dajian Li,Jiayu Ruan,Haitao Yang,Wenhao Cui,Bai Wang,Fan Wang,Zhenfeng Zhao,Yuxin Zhang

doi:10.3389/feart.2021.767738

Abstract

Due to the extensive development of fractures and serious heterogeneity in fractured reservoirs, it is difficult for the traditional numerical simulation method to invert its geology, which greatly limits the efficiency and accuracy of simulation and cannot realize the real-time optimization of production scheme. The connectivity model can only consider the two characteristic parameters of conductivity and connectivity volume, which does not involve complex and rigorous geological modeling. It can quickly and accurately reflect the state of the real reservoir, greatly reducing the simulation time, and is suitable for real-time production performance prediction of the reservoir. Due to the large difference in conductivity of fractured reservoirs, the difficulty of fitting increases. In this paper, the connectivity model is first applied to fractured reservoirs to realize the production dynamic simulation of fractured reservoirs. The optimization principle is used to optimize the injection-production scheme with the economic net present value as the objective function. In order to verify the method, the connectivity model is applied to Mu 30 of Changqing Oilfield in this paper. The results show that this method can effectively reflect the real production situation of the oilfield and the connectivity of the reservoir, and the simulation time is relatively fast. After optimization, the cumulative oil production of the reservoir increases by 8.1%, the cumulative water injection decreases by 2.3%, and the rising rate of water cut decreases by 58.8%, indicating that the connectivity model can realize the real-time production optimization of the reservoir.

Highlights

With the progress of global, low permeability reservoir exploration and fracturing technology, the development of fractured reservoirs has become more and more common
As can be seen from the formula (3), if ro 1, rw 0, b 0, rwi 0, the objective function is changed from economic net present value to cumulative oil production
The simulation results show that the model can effectively reflect the real production and connectivity of fractured reservoirs, and the simulation time is relatively fast, which can lay the foundation for real-time production optimization of reservoirs

Summary

Introduction

With the progress of global, low permeability reservoir exploration and fracturing technology, the development of fractured reservoirs has become more and more common. The BP2030 World Energy Outlook report shows the world’s tight oil reservoir development prospects. Most of the exploitation of tight oil needs fracturing, so it can be said that fractured reservoirs are the main theme of future reservoir exploitation. A fractured reservoir is a reservoir where fractures have an important impact on fluid flow or effective permeability of porous media (Xu, 2017). It is a manifestation of reservoir permeability and Optimization Method of Fractured Reservoir porosity heterogeneity. One of the reasons for this situation is the lack of understanding of fracture identification, distribution law and fluid flow dynamics in fractures (Xu et al, 2021)

Methods

Results

Conclusion