| With the development of water flooding in ordinary heavy oil field of Liaohe Oil Field, more and more blocks have become into the"two high period"know as high water content and high degree of reserve recovery, the producing capacity decreased year by year; the probability to the infilled adjustment for water flooding block becomes less. The new well producing capacity decreased year by year. According to these problems in the water flooding blocks, in order to look for method to enhance oil recovery, Hai 1 block with high water content period was chosen to go on the indoor experiment of chemical flood. Through the analysis of reservoir geologic feature and development condition, it is believed to be suitable for surfactant alkali water flooding. Alkali and surfactant can make surfactant produce ultra low interfacial tension with oil in low concentration. With the experiments of different interfacial activity of alkali to aqueous surfactant solution, several kinds of different combination of surfactant /alkali are selected, interfacial tension value are all under 10-3mN/m order of magnitude. The compatibility and salt-resisting experiments are carried on to increase the displacement characteristics. In order to improve the solubility of surfactant in highly salt solubility system, several increasing solvents are selected according to the different dispensation of surfactant with caustic. According to comprehensive evaluation of the flooding dispensation, four suitable dispensations of surfactant s/ alkali for Hai 1 block.are found. The indoor experiment shows that the flooding dispensations could increase the displacement efficiency more than 20%, the interfacial tension with oil is under 10-3mN/m, and has the good compatibility with reservoir effluent. The static and dynamic emulsification test shows that Alkali/surfactant compound system can emulsify with oil automaticly to form emulsion with better emulsion effect, relatively high emulsion steady and high interfacial activity.
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