裂缝性油藏低渗透岩心自发渗吸实验研究  

Experimental study of spontaneous imbibition in low permeability core,fractured reservoir

作　　者：李爱芬[1] 凡田友[1] 赵琳[1] 

机构地区：[1]中国石油大学(华东)油气渗流研究中心,山东青岛266555

出　　处：《油气地质与采收率》2011年第5期67-69,77,共4页Petroleum Geology and Recovery Efficiency

基　　金：国家科技重大专项课题(十二五)"剩余油形成机理及定量分析方法研究"(2008ZX05014-003-006HZ)

摘　　要：裂缝性低渗透油藏注水开发时,注入水沿裂缝窜流,油井含水率高,地下注水波及效果差,油层水淹后仍有大量原油滞留在基质岩块中。渗吸排油是裂缝性低渗透油藏重要的采油机理,为研究各种因素对渗吸效果的影响,采用胜利油区纯梁采油厂天然低渗透岩心,通过在地层水和表面活性剂溶液中的自发渗吸实验,研究了润湿性、温度、粘度、界面张力等因素对渗吸的影响规律。实验结果表明:温度不是影响渗吸的直接因素,而是通过改变模拟油的粘度来间接影响渗吸;润湿性、模拟油粘度以及界面张力是影响自发渗吸的主要因素,岩石越亲水,模拟油粘度越低,渗吸采收率越高;对于亲水岩心,渗透率和界面张力控制着渗吸发生的方式;不同渗透率级别对应一个最佳的界面张力范围,在该范围内,渗吸的采收率最高;对于亲水—弱亲水岩心,岩心渗透率越大,所对应的最佳界面张力越低。Low permeability fractured reservoir has a poor recovery by water flooding,there is still a lot of residual oil left in the matrix after water flooding.It is an important mechanism that the oil flows into the fracture from matrix by imbibition,and various influencing factors are still needed to be studied.In this paper,we studied a number of factors,such as wettability,temperature, viscosity,interfacial tension,and so on,which affect the imbibition through spontaneous imbibition experiments in formation water and surfactant solution,based on the natural low permeability core from Chunliang oil production factory.The results show that the temperature is not the direct factor of imbibition,but it can affect the imbibition indirectly by changing the oil viscosity.The main factors affecting spontaneous imbibition are wettability,oil viscosity and interfacial tension.The more hydrophily of the core,the lower the oil viscosity,and the higher imbibition oil recovery.For the water wet core,it is the permeability and interfacial tension which control the imbibition mode.Different permeability levels have different optimal range of interfacial tension values,in which imbibition has the highest recovery.For the water-wet core and weak-water-wet core,the higher the permeability,the lower the optimal interfacial tension.

关 键 词：低渗透 自发渗吸 润湿性 界面张力 渗吸采收率 

分 类 号：TE357[石油与天然气工程—油气田开发工程]