SPE Reservoir Engineering, Vol.10, No.3, 194-197, 1995
LABORATORY INVESTIGATION OF COMBINATION OF ALKALI SURFACTANT POLYMER TECHNOLOGY FOR DAQING EOR
Alkali/surfactant/polymer (ASP) formulas were developed for the Daqing oil field, Peoples Republic of China, with two surfactants from the U.S. (Petrostep B-100 and a blend of TRS-ls and TRS-40) and one Chinese surfactant (PS-D-2). Each ASP solution gave interfacial tension (IFT) values in the range of 1 x 10(-3) mN/m. Rheologic studies with polyacrylamide polymers indicate that solution viscosity decreases with alkali addition, as does the pseudoplasticity of the solution. Addition of surfactant to the alkali/polymer solution increases the solution viscosity with no slope change in the viscosity-vs.-shear-rate plot. Incremental oil recovery was higher than that with waterflood; 20% original oil in place (OOIP) for 0.2-PV ASP injection and 33% OOIP for 0.3-PV ASP injection in Daqing core. Surfactant and alkali retention were both < 1 mg/g sand. The positive results of this laboratory study provided a fluid formula for a pilot ASP flood in the Daqing oil field.