无碱二元复合体系驱油特性研究

针对高温高盐油藏化学驱的需要,研究了一种无碱二元复合驱油体系。该驱油体系由0.175%缔合聚合物和0.2%高界面活性表面活性剂组成。抗温抗盐性能评价试验表明,在矿化度30000mg/L和温度75℃以下,该体系可以同时获得40mPa.s以上的粘度和超低界面张力。非均质岩心模拟驱油试验证实,水驱达到含水70%时,该二元体系可以继续提高34%的采收率。在化学驱阶段,二元复合驱和聚驱可以获得大致相当的采收率,并且在后续水驱阶段还可以额外贡献约6%的采收率。同时发现采用缔合聚合物的聚驱和二元复合驱有两个明显的含水漏斗。

Properties Investigation of Surfactant-polymer Flooding System for EOR

A surfactant-polymer(SP) flooding system was designed and developed for chemical flooding in high temperature and high salinity reservoirs with compounding surfactant GA and hydrophobically associated polymer(HAPAM) as the primary ingredient.The SP flooding system was consisted of 0.2 %(w/w) surfactants and 0.175%(w/w) HAPAM.The high temperature-resisting an anti-salt tests indicated that more than 40mPa·s viscosity and low interfacial tension could be obtained under conditions of 30000mg/L salinity and 75℃.Heterogeneous core flooding test results show SP flooding could increase recovery by 34% OOIP at the water cut of 75%.At the 2nd stage of chemical flooding,the composite polymer(SP) system could be used to obtain equal recovery rate with that of polymer flooding,but SP system could contribute additional 6% recovery rate owing to surfactant retention.In chemical flooding and chase water flooding procedure,it is found out that there are two significant aquifer funnels.