Evaluation on Polymer Emulsion for Chemical Flooding in Offshore Oilfield

Due to the application problems of polymer powder flooding in offshore oilfield, such as the long dissolve time, complex solution made-up processing of polymer powder, study on characteristics of polymer emulsion EPAM453 and its oil displacement efficiency have been conducted. The results showed that EPAM453 can dissolve quickly within three minutes and has greater temperature and concentration range for dissolving, compared with the polymer powder product AP-P4 which is used in the offshore oilfield at present. Salt tolerance evaluation showed that the tolerance ability of EPAM453 to monovalent salt is weaker than AP-P4, but the tolerance ability of EPAM453 to bivalent salt is equal to AP-P4. The apparent viscosity of EPAM453 polymer solution can meet the requirements of polymer flooding in Jinzhou 9-3 oilfield. Shear, aging and freeze-thaw resistance evaluation showed that EPAM453 has good resistance to shear and aging, and can be stored and used in low temperature. The residual resistance factor of EPAM453 polymer solution is between 4 and 8, and the product has good mobility control ability. The oil displacement experiment results showed that the increase of recovery efficiency by EPAM453 polymer flooding was greater than 8% under the simulated conditions of Jinzhou 9-3 oilfield. The study provides a theoretical basis for the application of polymer emulsion products in offshore oilfield.