超低渗油田蓄能重复压裂增能机理  

Energy Enhancement Mechanism of Energy Storage Refracturing in Ultra-low Permeability Oil Fields

作　　者：达引朋[1] 薛小佳[1] 刘明[1] 史佩泽 曲鸿雁[2] 周福建[2] DA Yin-peng;XUE Xiao-jia;LIU Ming;SHI Pei-ze;QU Hong-yan;ZHOU Fu-jian(Oil and Gas Technology Institute, Petro China Changqing Oilfield Company, Xi'an 710018, China;Unconventional Petroleum Research Institute, China University of Petroleum, Beijing 102249, China)

机构地区：[1]中国石油长庆油田分公司油气工艺研究院,西安710018 [2]中国石油大学(北京)非常规油气科学技术研究院,北京102249

出　　处：《科学技术与工程》2021年第33期14139-14146,共8页Science Technology and Engineering

基　　金：中国石油天然气股份有限公司科技项目(2102-2-2);国家自然科学基金(52174044,52004302);中国石油大学(北京)科研基金(ZX20200134)。

摘　　要：鄂尔多斯盆地华庆超低渗油藏地层压力系数低,老井长期生产后近井区域地层能量亏空严重,制约了重复压裂转向裂缝的扩展,造成油井稳产时间短。蓄能重复压裂能有效补充地层能量,但压裂增能机理不明,地层压力提升幅度和规律不清。在分析地质和开发特征基础上,通过地质油藏精细建模和油藏数值模拟,研究了闷井期间井底压力演化、裂缝和基质内压力传播规律,以及注入量和闷井时间等因素对蓄能效果和产量的影响,从微观角度揭示了关井期间压裂增能机理,为现场“压裂-增能-驱油”工艺优化提供理论指导。Huaqing ultra-low permeability reservoir in Ordos Basin is characterized with low formation pressure coefficient.Serious energy deficit occurs in the near wellbore area of the reservoir after long-term production in the old wells,which restricts the fracture diversion and the stable production time of oil well during the refracturing.Energy storage refracturing can effectively supply the formation energy,whereas the mechanism of fracturing energy enhancement is unknown,and the increasing range of formation pressure is unclear.The fine geological and fracturing energy enhancement model was established based on the analysis of the geological characteristics and the problems in the development of the Huaqing oil field.In addition,the evolution of bottom hole pressure and the law of pressure propagation in fracture and matrix were clarified through numerical simulation.Moreover,the effects of injection rate and shut-in time on energy enhancement and production were analyzed.The mechanism of fracturing energy enhancement during shut-in was revealed from a micro perspective.The work provides theoretical guidance for the on-site“fracturing-energized-displacement”process optimization.

关 键 词：超低渗 重复压裂 闷井 增能机理 数值模拟 

分 类 号：TE357[石油与天然气工程—油气田开发工程]