After the success of polymer flooding in Daqing, two alkaline-surfactant-polymer (ASP) floods have been conducted to (1) increase oil recovery further (2) study the feasibility of ASP flooding (3) provide technical and practical experience for expanding the ASP pilots. Inverted five spot pattern is adopted in both pilots. Pilot 1 (PO) is located in the West Central area of Daqing Oil Field and consists of 4 injectors and 9 producers. Pilot 2 (XF) is located in the South area of Daqing Oil Field and has 1 injector and 4 producers. The crude oil of both pilots have high paraffin content and low acid value. Compared to PO, XF has characteristics of lower heterogeneity, lighter oil and higher recovery by water flooding. For each pilot, after extensive screening, an ASP system has been determined. The ASP systems all feature very low surfactant concentration and wide range of ultra low interfacial tension with change of concentration of any of the three components. Core flooding and numerical simulation show more than 20% OOIP incremental recovery by ASP over water flooding for both pilots. By the end of May, 1995, 100% of ASP slug and 100% of the polymer buffer have been injected inmore » the pilots. Production wells showed good responses in terms of large decrease in water cut and increase in oil production. The performance of each pilot has followed the numerical simulation predication very well, or even a bit better. Emulsions showed up in producers, but the emulsions are easy to be broken by a special de-emulsifier. No formation damage and scaling have been detected. The ASP flood pilot tests are technically successful and, based on the preliminary evaluation, economically feasible. Therefore, in the near future, much larger scale ASP flood field tests are going to be performed at several districts in Daqing Oil Field.« less