METHOD FOR RECOVERING OIL FROM SUBTERRANEAN DEPOSITS BY EMULSION FLOODING

摘要

Recovery of largely emulsion-free oil, from a subterranean deposit of average or high salinity is disclosed. The method involves injecting an emulsion into an injection borehole, carboxy-methylated oxethylate being used as the emulsifier and being employed in such a manner that the phaseinversion-temperature of the system comprising deposit oil/formation water/ surfactant/possible additives, is from 0 to 10.degree.C above the temperature of the deposit.