摘要
聚合物/表表面活性剂二元复合驱是在水驱后提高不同模态砾岩油藏采收率的重要技术,但应用二元复合驱时,对不同砾岩油藏却产生了不同的驱油效果,而对于该方面的研究当前还比较少。基于室内岩心驱油实验结合核磁共振在线监测和CT扫描,对单、双和复模态砾岩油藏在不同开采阶段的剩余油分布和不同孔隙内油的采出规律进行研究。结果表明,水驱阶段,复模态岩心的采收率最高,其次是单模态岩心,双模态岩心的采收率最低,3种模态岩心采收率分别为31.4%、25.8%、33.4%。而二元复合驱阶段岩心提高采收率幅度为:双模态>复模态>单模态,分别提高了27.9、26.4、19百分点,且3种模态岩心在二元复合驱时的孔隙动用下限均降低,且复模态岩心的降低幅度高于双模态岩心和单模态岩心。单、双、复模态岩心的非均质性逐渐增强,单模态岩心水驱阶段均匀驱替,采收率高;复模态岩心中的油主要集中在孔径为32.7~52.5μm的优势大孔中,在水驱阶段油也被大量采出,导致剩余油量低;双模态岩心中大孔内油量较复模态低,水驱采收率低,剩余油量高。在二元复合驱阶段,由于调驱作用和水驱后剩余油量影响,双模态岩心提高采收率效果最好,其次是复模态岩心。
In view of the problem that the production rules of conglomerate reservoirs with different modes in polymer/surface binary composite flooding stage have not fully been studied clearly,the residual oil distribution and pore production features of conglomerate reservoir at different stages of production were studied through indoor core oil displacement experiment combined with NMR online monitoring and CT scanning analysis.The results showed that the oil recovery of the single,dual and complex mode cores in the water drive stage was 31.4%,25.8%and 33.4%,respectively,while the enhanced oil recovery of the dual mode rock was higher than that of the complex mode rock and higher than that of the single mode rock in the binary composite flooding stage,which was 27.9,26.4 and 19 percentage points,respectively.Moreover,the pore limit of oil production was lower than that of the water production stage,and reduction amplitude of the complex mode core was higher than that of the single core and dual core.The heterogeneity of single,dual and complex mode cores was gradually enhanced,resulting in uniform displacement of single mode cores and high oil recovery in the water flooding stage.While the oil in complex mode rock was mainly concentrated at large hole with pore size of 32.7—52.5μm,which was also largely produced in the water drive stage.In the dual modal conglomerate rock,the oil volume in the large pores was lower than that in the complex conglomerate rock,resulting in that the water flooding recovery rate was lower,and the remaining oil volume was higher.In the binary flooding stage,based on the effect of profile control and flooding and the influence of residual oil after water flooding,the dual mode core had the best effect of enhancing oil recovery,followed by the complex mode core.
作者
苗伟
王志刚
刘昱瑭
刘晶晶
广怡初
张瑞
MIAO Wei;WANG Zhigang;LIU Yutang;LIU Jingjing;GUANG Yichu;ZHANG Rui(No.6 Oil Production Plant,China National Petroleum Corporation,Changqing Oilfield Branch Company,CNPC,Xi’an,Shaanxi 745100,P R of China;Laojunmiao Oil Production Plant,Yumen Oilfield Branch Company,PetroChina,Jiuquan,Gansu 735200,P R of China)
出处
《油田化学》
CAS
CSCD
北大核心
2024年第2期310-314,共5页
Oilfield Chemistry
关键词
砾岩油藏
核磁共振
CT扫描
剩余油
采收率
conglomerate reservoir
nuclear magnetic resonance
CT scanning
remaining oil
recovery ratio
