Study on the reaction of alkali/surfactant/polymer and reservoir cores in Daqing Oilfield

The alkali/surfactant/polymer (ASP) flooding technology can significantly enhance oil recovery, but the ASP injection fluid can easily react with reservoir cores, resulting in scaling, plugging and the recovery rate reducing. So it is necessary to study dissolution, transportation and plugging rules of ASP in reservoir. In this paper, the reaction process of ASP and reservoir cores in Daqing Oilfield was analyzed by X-ray diffraction(XRD), Fourier transform infrared spectroscopy(FT-IR), polarizing microscope(PM), environmental scanning electron micoscope(ESEM) and energy dispersive spectroscopy(EDS). The study on reaction kinetics was conducted and the dissolution kinetics equations of Si and Al were calculated. The results show that albite, nosean, buddingtonite are respectively formed in Nanwuqu, Xingshugang, and Lamadian cores after 50 days. The dissolved amount of Si is three to four times than that of Al and the kinetics equations of Al are in the power function form. The replacement of NaOH with KOH or Ca(OH)₂ is advised.