摘要
针对鄂尔多斯盆地特低渗透油藏注水井注水压力高、注水量达不到配注要求、注水开发效果较差等问题,在储层特征分析基础上,通过室内实验优选出了具有良好界面活性、润湿性能的双子表面活性剂SG-12、氟碳表面活性剂FT-Z,结合防膨剂FP-101,建立了一种复合表面活性剂降压增注(JYZZ)体系,并对其综合性能进行了评价。结果表明:特低渗透岩心注入JYZZ体系后,油水等渗点明显右移,两相渗流区域明显变宽,残余油饱和度降低,水相相对渗透率明显升高;水驱压力稳定后,注入6PV的JYZZ体系,可使岩心注入压力降低35%以上,并能使采收率提高5%以上。现场试验表明,6口注水井采用JYZZ体系后注水压力显著下降,注水量显著提升,平均有效期超过300 d,降压增注效果明显。研究成果对特低渗透油藏降压增注具有指导意义。
Aiming at the problems of high water injection pressure,insufficient water injection rate and poor waterinjection-development effects in the ultra-low permeability oil reservoirs in Ordos Basin,based on the analysis of the reservoir characteristics,gemini surfactant SG-12 and fluorocarbon surfactant FT-Z with much better interfacial activity and wetting performance are selected through laboratory experiments,and combined with anti-swelling agent FP-101,a compound surfactant depressurizing-injection augmenting system(JYZZ)is developed,and its comprehensive performance is evaluated. The results show that after injecting JYZZ system into the ultra-low permeability core,the oil-water isotonic point moves to the right,the two-phase flow areas widen,the residual oil saturation decreases,and the relative permeability of the water phase increases. After the stabilization of the water flooding pressure for the core,injecting 6 PV JYZZ system makes the injection pressure reduced by more than 35% and the recovery rate is enhanced by more than 5%. The field test shows that the injection pressures in 6 water injectors are significantly decreased,the injection water volumes are obviously increased and average effective period is more than 300 d,with obvious effects of reducing the pressure and increasing the injection rate. The study achievements possess the guiding significances for the depressurizing and injection enhancing in ultra-low permeability oil reservoirs.
作者
李艳
LI Yan(Dingbian Oil Production Plant of Yanchang Oilfield Co.Ltd,YuLin 718600,China)
出处
《大庆石油地质与开发》
CAS
CSCD
北大核心
2022年第1期104-110,共7页
Petroleum Geology & Oilfield Development in Daqing
基金
“十三五”国家科技重大专项“低渗、特低渗油藏规模有效动用关键技术”(2017ZX05013001)。
关键词
特低渗透油藏
注水井
降压增注
渗流特征
界面活性
润湿性能
ultra-low permeability oil reservoir
water injector
depressurization and injection enhancement
flow characteristic
interfacial activity
wettability
