DLF低张力泡沫体系的评价

基于研制出的适用于高温高盐油藏的新型起泡剂DLF，对其表/界面张力、起泡能力、稳定性、耐油性等静态性能以及驱油效率和提高采收率等动态性能进行了测试和评价。实验结果表明，DLF的最佳适用浓度为0.5%，在优选浓度下的表/界面张力以及起泡性能和稳定性均能达到最优水平，且DLF泡沫具有很好的耐油性能以及洗油能力，模拟油藏条件下可提高洗油效率达23.06%。在低张力洗油和泡沫的调堵、分流的综合作用下，DLF低张力泡沫驱可以维持较长时间的同步分流调剖效果，最大限度地挖潜高、低渗岩心，尤其是低渗岩心中的剩余油，后续水驱结束后，综合采收率提高28.9%，低渗岩心提高约48.8%，高渗岩心提高约21.6%。

Performance Evaluation of DLF Low Tension Foam System

On the basis of new type of foaming agent DLF for reservoirs with high temperature and high salinity, , its comprehensive performances were tested and evaluated, such as the surficial/interfacial tension, foamability, stability, oil resistance, oil displacement efficiency, et al. The results showed that, at the optimal mass fraction of 0.5%, the DLF system had the lowest surficial/interfacial tension, and highest high foamability, stability and oil resistance. The displacement efficiency of DLF surfactant system could reach 23.06% higher than that of water under stimulated formation condition. Under the comprehensive action of powerful washing and foam plugging and diversion, synchronal diversion of DLF low tension foam flooding could be maintained for a longer period, and the remaining oil in high/low permeability core, especially low one, could be displaced to the max degree. Hence, by the end of subsequent water flooding, the integrated oil recovery was increased by 28.9%, thereinto, low permeability core was increased by 48.8%, and the high permeability one was increased by about 21.6%.