CO2混相驱提高石油采收率实践与认识  

Practice and understanding of enhancing the oil recovery by CO2 miscible flooding

作　　者：张海龙[1] ZHANG Hailong(PetroChina Jilin Oilfield Company,Songyuan 138000,China)

机构地区：[1]中国石油天然气股份有限公司吉林油田分公司,吉林松原138000

出　　处：《大庆石油地质与开发》2020年第2期114-119,共6页Petroleum Geology & Oilfield Development in Daqing

基　　金：“十二五”国家重大科技专项“松辽盆地CO 2驱油与埋存技术示范工程”(2011ZX05054)。

摘　　要：吉林油田黑59区块CO2驱油先导试验在注气一段时间以后,仍有部分油井不见效。为了明确影响CO2混相驱提高石油采收率的原因,开展了岩心驱替实验和岩心核磁共振检测实验。岩心驱替实验结果表明,CO2混相驱可以降低CO2—原油体系的启动压力梯度。核磁共振实验结果表明,CO2混相驱可以驱动水驱无法动用的低孔低渗储层中的原油。在室内实验研究的指导下,对现场不见效油井的低渗储层进行补孔压裂试验,见到了显著的增油效果,验证了CO2驱在低渗透非均质储层中的驱替波及效率更高。After a few time intervals of CO2 flooding pilot test in Block Hei-59 in Jilin Oilfield,there are still part of the oil wells not affected.In order to clarify the reason of influencing the oil recovery enhancement of the CO2 miscible flooding,the tests of the core flooding and core nuclear magnetic resonance detection were conducted.The results of the former test show that the CO2 miscible flooding can reduce the start-up pressure gradient of the CO2-crude oil system;the results of the latter test show that the CO2 miscible flooding can displace the crude oil in the low-porosity and low-permeability reservoirs which cannot be flooded by the water.Guided by the indoor test study,the perforation adding and fracturing tests were engaged for the low-permeability reservoirs for the oil wells which were not affected in the field,the remarkable oil-incremental effect was shown,thus the fact was verified that the flooded and swept efficiencies of the CO2 miscible flooding are more higher in the low-permeability heterogeneous reservoirs.

关 键 词：CO2驱 启动压力梯度 核磁共振 提高采收率 

分 类 号：TE357.45[石油与天然气工程—油气田开发工程]