PILOT TESTS OF ALKALINE SURFACTANT/POLYMER FLOODING IN DAQING OIL-FIELD/

After the success of polymer flooding in Daqing, two alkaline/surfacta nt/polymer (ASP) floods were conducted to increase oil recovery furthe r to study the feasibility of ASP flooding, and to provide technical a nd practical experience for expanding the ASP pilots. The crude oil of both pilots has a high paraffin content and low acid value. After ext ensive screening, an ASP system with very low surfactant concentration and wide range of ultralow interfacial tension (IFT) with any concent ration change of the three components was determined for each pilot. C oreflooding and numerical simulation show more than 20% original-oil-i n-place (OOIP) incremental recovery by ASP over waterflooding for both pilots. The ASP flood pilot tests are technically successful and, on the basis of preliminary evaluation, economically feasible; therefore, much larger-scale ASP-flooding field tests are planned in Daqing oil field in the near future.