Abstract
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%.