二类油层中三元复合驱体系的损耗及有效作用距离  

Chemicals loss and effective distance of ASP flooding in second-class oil layers

作　　者：刘刚[1] 侯吉瑞 李秋言 王少朋 李明远[1,2] 刘帅[3] 

机构地区：[1]中国石油大学提高采收率研究院,北京102249 [2]中国石油大学重质油国家重点实验室,北京102249 [3]天津工业大学机械工程学院,天津300387

出　　处：《中国石油大学学报（自然科学版）》2015年第6期171-177,共7页Journal of China University of Petroleum(Edition of Natural Science)

基　　金：国家自然科学基金项目(51174216);国家科技重大专项(2011ZX05052)

摘　　要：采用天然露头岩心进行驱油物理模拟,研究三元复合体系在地层中不同运移距离下的界面张力以及化学剂损失规律。结果表明:二类油层中复合体系的各组分损失严重,表面活性剂在运移前20%距离后即损失了80%,此时碱、聚合物的损失率也达到23%和12%;复合体系运移全程距离后表面活性剂、碱和聚合物的损失率分别达到了92%、42.8%和31%,损失量都较为显著。复合体系的化学剂主要损失在注入井附近地层中,且这部分损失主要为'无效损耗',对采收率的贡献值有限。化学剂的损失导致复合驱的驱油效果也逐步降低。复合体系的超低界面张力实际的有效作用距离仅为前20%距离,因而对提高采收率的贡献十分有限,而对20%井距之后的水驱残余油的进一步启动则是三元复合驱发展的潜力方向。The interfacial tension ( IFT) change and the chemicals loss of alkali/surfactant/polymer ( ASP) at different mi-gration distances in the oil layer were investigated through the simulation experiments of oil displacement using natural out-crops cores. The results show that the chemical loss of ASP in second class oil layer is serious. The loss percentage of surfac-tant is 80% in the former 20% migration distance, and the loss percentage of alkali and polymer is 23% and 12% respec-tively. After ASP flooding 100% migration distance, the loss percentages of surfactant, alkali and polymer reach 92%, 42. 8% and 31% respectively, which is significant. The chemicals loss occurs near the injection well in the oil layer, which is mainly useless and has limited contributions to the enhanced oil recovery. And this loss leads to gradually reduce the oil displacement efficiency of ASP flooding. Only the top 20% of the distance of the ultra-low IFT for ASP system is effective, therefore its contributions to oil recovery enhancement is extremely limited. The displacement of residual oil after former 20%well spacing is the potential direction of ASP flooding development.

关 键 词：三元复合驱 大庆二类油层 露头岩心 吸附滞留 超低界面张力 提高采收率 

分 类 号：TE357[石油与天然气工程—油气田开发工程]