一种耐盐微乳液化学驱油剂的研制及性能评价

Development and performance evaluation of a salt-tolerant microemulsion chemical oil displacement agent

长庆油田部分区块经一次及二次采油后,仍有接近一半的剩余油未被采出,表面活性剂驱油目前是能够提高采收率的一种重要技术手段。本文结合低渗透油藏采出水矿化度高的情况,优选表面活性剂RYQ、RZ-1作为复配体系,测定了体系的油水界面张力、配伍性、复配比例、最佳盐浓度及洗油效率。实验结果表明,该耐盐表面活性剂体系RYQ/RZ-1在质量分数为0.9%可实现数量级为10-3mN/m的超低界面张力;体系浓度为0.9%,复配比例为2∶1,最佳盐浓度为0.5%;洗油效率为25%左右,该体系具有良好的性能。

After primary and secondary oil recovery in some blocks of Changqing oilfield,nearly half of the remaining oil has not been produced.Surfactant flooding is currently an important technical means to improve the oil recovery rate.In this paper,combined with the high salinity of produced water in low permeability reservoirs,the surfactant RYQ and RZ-1 were selected as the compound system,and the oil-water interfacial tension,compatibility,compound ratio,optimum salt concentration and oil washing efficiency of the system were determined.The experimental results show that the ultra-low interfacial tension of the salt-tolerant surfactant system RYQ/RZ-1 can be achieved at the mass fraction 0.9%of 10-3mN/m.The concentration of the system was 0.9%,the compound ratio was 2∶1,and the optimum salt concentration was 0.5%.The oil washing efficiency is about 25%,and the system has good performance.