METHOD FOR DEVELOPMENT OF OIL DEPOSIT Russian patent published in 1998 - IPC

FIELD: oil production industry. SUBSTANCE: this relates to development of oil deposits with application of flooding. According to method, oil deposit is flooded with water-gas solution by pumping this water-gas solution together with surface-active agent through injection wells. Surface-active agent is added to water before its mixing with gas. Used as water-gas solution is single-phase gas solution in pretransitional phase condition at ratio of gas and water volumes which ensures complete saturation of water with gas at bed conditions. Maintained in process of injection is ratio of bottom-hole pressure to bed pressure to be equal to less than two. Used as gas phase in water-gas solution is hydrocarbon gas. Used as surface-active agent is cationic surface-active agent in amount of 0.01-1.0%. Application of aforesaid method increases oil recovery from bed due to enlarged embracing of bed by substitution operation. EFFECT: higher efficiency. 1 tbl