EOR Technologies: Physico-Chemical Aspects

Abstract

The application of self-regulating oil-displacing systems is considered to be a promising trend in the development of physico-chemical EOR methods. Technologies intended to increase conformance predominate. EOR technologies, where heat energy of the formation is used to generate alkaline buffer systems, CO2 and gels increasing oil displacement and conformance, have wide potentialities. Such methods have been realized in the technologies developed at the Institute of Petroleum Chemistry SB RAS (IPC). Hydrolysis, hydrolytic polycondensation and coagulation in the system carbamide – aluminum salt – surfactant – water is the physico-chemical base for the technologies involving alkaline buffer systems, CO2 and inorganic gels. To prepare thermoreversible polymer gels one uses change of phase from solution to gel in the system: cellulose ether with a lower critical dissolution point – water. Presented are the results obtained on the application of physico-chemical EOR methods and technologies developed at IPC in oil fields of Russia. The technologies proved to be economically effective and environmentally safe. The period of payback is 5-12 months.