渤中25-1沙二段低渗储层空气驱用防窜体系性能室内研究

Laboratory Research on Performance of Channeling Prevention System for Sha 2 Reservoir of Bozhong 25-1 Oilfield

为了抑制低渗油田注空气过程中气窜的发生,提高注气效果,对筛选出的复合防窜泡沫体系PMFC-2的抑制气窜效果和影响因素进行了室内试验研究。结果表明:PMFC-2在含油条件下具有一定的发泡性能,泡沫流体在低渗油田的注入速度以及注入方式是影响泡沫窜流的主要因素;脉动式注入方式和提高注速是改善窜流的有效途径,能够有效提高原油采收率,采用水气交替注入方式可在水驱基础上提高采收率24.7%,采用脉动式注入方式可在水驱基础上提高采收率30%。

To control the gas channeling that would occur during air injection process in low permeability oilfield and improve the efficiency of air injection,a laboratory research on the efficiency of compound channeling prevention foam system PMFC-2 in inhibiting channeling and on the factors affecting the efficiency was carried out.The results of laboratory research have shown that PMFC-2 has foaming capacity to a certain extent when oil is present,foam liquid injection rate and injection mode are the major factors affecting foam channelling in low permeability oilfield,use of pulsing injection mode and increase of injection rate can reduce channelling and thus increase oil recovery efficiency significantly,recovery efficiency can be increased by 24.7%when water injection and air injection are performed alternately compared to that when water flooding is performed,and recovery efficiency can be increased by 30%when pulsing injection is performed compared to that when water flooding is performed.