羊三木稠油油藏复合驱提高采收率实验研究

Experimental Research on Combination Flooding System for EOR in Yangsanmu Heavy Oil Reservoir

针对羊三木普通稠油油藏特征,通过界面张力实验和乳化实验筛选了聚表(SP)二元复合驱体系,体系组成为2 000 mg/L表面活性剂PS–2+1 000 mg/L聚合物HPAM。该聚表二元体系使油水界面张力降至10 2mN/m数量级,并形成稳定的O/W型乳状液。乳状液60 min析水率为10.8%,降黏率为95.8%。岩芯流动实验表明,注入0.3 PV驱油体系采收率提高幅度分别为聚表二元复合驱15.7%、聚合物驱10.8%和表面活性剂驱7.9%。聚表二元复合驱提高羊三木稠油油藏采收率效果最好,适合用于提高普通稠油油藏采收率。

A surfactant-polymer （SP） system screened by interfacial tension experiments and Emulsifying test is prepared for EOR in view of Yangsanmu heavy oil reservoir. This system is composed ofa surfactant （PS-2） with a density of 2 000 mg/L and HPAM with a density of 1 000 mg/L, which can reduce the oil-water interracial tension to the magnitude of 10-2 mN/m and form stable water-in-oil（W/O） emulsion with a water separation rate of 10.8% and a viscosity-reducing rate of 95.8% for 60 min. Core flow experiments demonstrate that the enhanced recovery of three different systems referring to SP, single polymer and single surfactant system is 15.7% , 10.8% and 7.9% respectively when 0.3 PV flooding system was injected. Thus, SP system is the best for EOR in Yangsanmu heavy oil reservoir, and is also helpful to applied to improve oil recovery for ordinary heavy oil reservoir.