摘要
在致密砂岩储层水平井重复压裂中,再次提升储层改造体积(SRV)是重复压裂成功的关键。由于初次压裂完井差、水力裂缝及天然裂缝的预置分布和动态应力变化认识不清,均衡扩展重复压裂多簇裂缝并获得理想改造效果颇具难度。为优化致密砂岩油藏水平井重复压裂储层改造效果,以长庆油田元284区块为例,构建了考虑四维动态地应力场的水平井重复压裂优化工作流程,引入有限元-离散裂缝网络(FEM-DFN)和四维动态应力场交叉耦合方法。在全三维压裂数值模型基础上,揭示多裂缝均衡扩展规律,优化压裂参数,实现提升致密砂岩油藏改造体积目标。研究结果表明,FEM-DFN方法可准确描述裂缝几何形态,通过优化压裂时机、加砂量、簇间距、压裂液量、施工排量等参数,提高了缝网复杂度和横向延伸程度。现场应用表明,考虑四维地应力动态变化的压裂工作流程效果显著,对国内致密砂岩油藏压裂优化具有指导意义。
In the development process of tight sandstone reservoir by horizontal well refracturing,the effective increase of the postfrac stimulated reservoir volume(SRV)is the key to success.Due to the limitation of initial fracturing completion process,the distribution of hydraulic fractures and natural fractures in the reservoir,and the dynamic change of pore pressure field and stress field caused by reservoir production and oil drainage after fracturing,however,different fracture clusters of horizontal well refracturing can hardly propagate evenly to achieve satisfactory stimulation effect.With Yuan 284 Block of tight sandstone reservoir in the Changqing Oilfield as an example,the optimization procedure of horizontal well refracturing process was established by using the finite element method-discrete fracture network(FEM-DFN)method and the four dimensional dynamic stress field cross-coupling method.After the full three dimensional volumetric fracturing numerical model considering the distribution of natural fractures and the dynamic change of in-situ stress was established,the optimization of horizontal well refracturing was studied.The multi-fracture even propagation laws of horizontal well refracturing in tight sandstone reservoirs were revealed,and the technological parameters of horizontal well refracturing were optimized,so as to reach the goal of increasing SRV of tight sandstone oil reservoir by horizontal well refracturing.It is indicated that FEM-DFN method can accurately and reliably describe the geometry of fractures induced by horizontal well refracturing.The fracture network complexity degree and lateral propagation degree after horizontal well refracturing can be improved by optimizing the technological parameters of horizontal well refracturing,including timing,sand amount in fractures,cluster spacing,injected fluid volume and construction displacement.Furthermore,the field implementation case indicates that the field implementation based on the horizontal well refracturing process considering the dynamic change of four dimensional in-situ stress presents remarkable effects,which is of important guiding significance for the process optimization of horizontal well refractuirng in tight sandstone oil reservoirs at home.The research provides a reference for the optimization of horizontal well refracturing process and a theoretical basis for the improvement of tight sandstone reservoir development.
作者
张铭海
雷征东
姜乐
朱海燕
邓家胜
ZHANG Minghai;LEI Zhengdong;JIANG Le;ZHU Haiyan;DENG Jiasheng(Baikouquan Oil Production Plant,PetroChina Xinjiang Oilfield Company,Karamay 834000,Xinjiang,China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation at Southwest Petroleum University,Chengdu 610000,Sichuan,China;Research Institute of Exploration and Development,PetroChina,Beijing 100083,China;Tahe Oilfield No.2 oil production plant of Sinopec Northwest Petroleum Bureau,Bayin golangzhou 841600,Xinjiang,China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation at Chengdu University of Technology,Chengdu 610000,Sichuan,China)
出处
《石油钻采工艺》
CAS
北大核心
2023年第1期97-107,共11页
Oil Drilling & Production Technology
关键词
致密砂岩油藏
致密油
四维地应力
全三维体积压裂数值模型
水平井重复压裂
tight sandstone oil reservoir
tight oil
four-dimensional in-situ stress
full-three-dimensional volumetric fracturing numerical model
horizontal well refracturing