摘要
针对超低渗透砂岩油藏水平井中段难以建立有效水驱驱替压力系统问题,提出在同一口水平井上采用封隔器、密封插管等工具,实现部分压裂缝注水、部分压裂缝采油,在同一水平井内形成分段同步注采的补能新方法,即水平井同井同步注采。该方法可缩小注入端与采出端的距离,快速建立有效水驱驱替系统;该方法将井间驱替转变为水平井段间驱替,将点状水驱转变为线状均匀水驱,可大幅提高水驱波及体积,缩短见效周期。研究表明:①超低渗透砂岩油藏水平井同井同步注采,注水段应选择天然裂缝方向与人工裂缝方向一致或天然裂缝不发育的层段,段间距60~80 m;②水平井同井同步注采除控制注入压力外,采用周期注水可降低随注水时间延长注水压力逐渐上升导致的地层天然裂缝开启、生长或地层破裂风险;③现场试验验证,水平井同井同步注采补能方法可有效提升单井产量且经济效益良好,可大规模应用于超低渗透砂岩油藏的开发。
It is difficult to build an effective water flooding displacement pressure system in the middle section of a horizontal well in an ultra-low permeability sandstone reservoir.To solve this problem,this study proposes to use packers,sealing cannula and other tools in the same horizontal well to inject water in some fractures and produce oil from other fractures.This new energy supplement method forms a segmental synchronous injection-production system in a horizontal well.The method can reduce the distance between the injection end and the production end,and quickly establish an effective displacement system.Changing the displacement between wells to displacement between horizontal well sections,and point water flooding to linear uniform water flooding,the method can enhance water sweeping volume and shorten waterflooding response period.The research shows that:(1)In the synchronous injection and production of horizontal well in an ultra-low-permeability sandstone reservoir,the water injection section should select the section where the natural fractures and artificial fractures are in the same direction or the section with no natural fractures,and the space between two sections should be 60-80 m.(2)In addition to controlling injection pressure,periodic water injection can be taken to reduce the risk of re-opening and growth of natural fractures or formation fracture caused by the gradual increase of water injection pressure with water injection going on.(3)Field tests have verified that this method can effectively improve the output of single well and achieve good economic benefits,so it can be widely used in the development of ultra-low permeability sandstone reservoirs.
作者
王晶
刘俊刚
李兆国
李洪畅
张皎生
李文青
张原立
平义
杨焕英
王萍
WANG Jing;LIU Jungang;LI Zhaoguo;LI Hongchang;ZHANG Jiaosheng;LI Wenqing;ZHANG Yuanli;PING Yi;YANG Huanying;WANG Ping(Exploration and Development Research Institute of PetroChina Changqing Oilfield Company,Xi’an 710018,China;National Engineering Laboratory for Exploration and Development of Low-Permeability Oil&Gas Fields,Xi’an 710018,China)
出处
《石油勘探与开发》
SCIE
EI
CAS
CSCD
北大核心
2020年第4期772-779,共8页
Petroleum Exploration and Development
基金
国家科技重大专项“鄂尔多斯盆地大型低渗透岩性地层油气藏开发示范工程(二期)”(2016ZX05050)
国家科技重大专项“低渗-超低渗油藏有效开发关键技术”(2017ZX05013-004)。
关键词
超低渗透油藏
砂岩油藏
水平井
分段压裂
同井同步注采
段间驱替
开发效果
ultra-low permeability reservoir
sandstone reservoir
horizontal well
staged fracturing
synchronous injection-production
intersegment displacement
development effect
