延长油田低渗储层新型降压增注体系研制及应用  

Development and application of a new depressurization and injection increasing system for low permeability reservoir in Yanchang Oilfield

作　　者：张刚[1] 韩迎鸽[1] 任春燕[1] 焦卫华[1] 吴利超 郑娜娜[1] 杨亮[1] 杜秀秀 ZHANG Gang;HAN Yingge;REN Chunyan;JIAO Weihua;WU Lichao;ZHENG Nana;YANG Liang;DU Xiuxiu(Dingbian Oil Production Plant of Yanchang Oilfield Co Ltd,Yulin 718500,China)

机构地区：[1]延长油田股份有限公司定边采油厂,陕西榆林718500

出　　处：《大庆石油地质与开发》2023年第3期107-114,共8页Petroleum Geology & Oilfield Development in Daqing

基　　金：国家科技重大专项“鄂尔多斯盆地大型低渗透油气藏开发示范工程”(2016ZX05050-006)。

摘　　要：针对延长油田低渗区块注水井压力升高、注水量下降以及常规酸化施工效果较差等问题,研制出了一种新型阳离子双子表面活性剂缓速剂HS-Ⅱ,并以此为基础,选择合适的主体酸液和缓蚀剂,制定了适合延长油田低渗储层的新型缓速酸降压增注体系。新型缓速剂HS-Ⅱ不仅具有良好的界面活性和润湿性能,还能有效提高主体酸液体系的缓速性能,当其质量分数为0.8%时,缓速率可以达到95%以上;新型缓速酸降压增注体系各处理剂之间具有良好的配伍性,且体系的溶蚀性能较好,其缓速性能和沉淀抑制性能明显优于常规土酸、多氢酸和现场缓速酸;新型缓速酸体系残酸的黏度和表面张力均较低,有利于其返排;岩心流动实验结果表明,随着新型缓速酸降压增注体系注入孔隙体积倍数的增大,岩心渗透率提高倍数明显增大,酸化效果明显优于常规土酸。新型缓速酸降压增注体系投入现场应用,能够明显降低注水井的注入压力,提高单井的日注水量,并且具有较长的有效期,实现了注水井长期降压增注的目的。研究成果可为延长油田低渗区块注水井的降压增注提供一定的技术支持。In view of the problems of increasing water injection pressure,decreasing water injection rate and poor effect of conventional acidizing operation in low-permeability block of Yanchang Oilfield,a new cationic gemini surfactant inhibitor HS-Ⅱis developed.Based on this,a new type of acid depressurization and injection increase system suitable for low-permeability reservoir of Yanchang Oilfield is studied by selecting appropriate main acid solution and corrosion inhibitor.The new retarder HS-Ⅱnot only has good interfacial activity and wettability,but also can effectively improve the retarded performance of the main acid system.When its mass fraction is 0.8%,the retarded rate reaches>95%.The new retarded acid depressurization and injection increasing system has good compatibility among various treatment agents,with good dissolution performance of the system.Its retarded performance and precipitation inhibition performance are obviously better than conventional mud acid,polyhydric acid and field retarded acid.The viscosity and surface tension of the residual acid in the new retarded acid system are low,being favorable for its flow-back.Core flow experiment shows that core permeability increases obviously with the increase of PV injected by the new slow acid depressurization and injection increasing system,with obviously better acidizing effect than that of conventional mud acid.Field application results show that the new slow acid depressurization and injection increase system can significantly reduce injection pressure of water injection wells and improve singlewell daily water injection,with a long response period,realizing the purpose of long-term depressurization and injection increase of water injection wells.It provides technical support for depressurization and injection increase of water injection wells in low permeability blocks of Yanchang Oilfield.

关 键 词：延长油田 低渗储层 阳离子双子表面活性剂 缓速酸 降压增注 

分 类 号：TE357[石油与天然气工程—油气田开发工程]