The Research Of Slug Optimization About Binary Complex System For Oil Displacement

Non-alkali binary compound flooding has became as a future researchfocus in the oil field to improve oil recovery technology. In this article, throughcore displacement experiment, we determined the non-alkali injection slug forbinary compound system: the front section of the plug(viscosity of40mPa.s)0.03PV+the binary composite system（S：0.3％＋HPAM：1600mg/L，viscosity of40mPa.s）0.3PV+subsequent protection slug HPAM(viscosity of30mPa.s)0.2PV+water drive. The natural core binary compound system toimprove oil recovery can achieve above16%. At the same time, we carried out3000centimeter long sand filling tube core displacement experiment, when it isone times pore volume of3000centimeter long model tube injection, when thewell spacing is more than30%, interfacial tension jumped to the order ofmagnitude of10-2mN/m. Even if the interface tension can not reach theultra-low interfacial tension, a larger proportion of residual oil can still beproduced. In the status of non ultra-low interfacial tension, emulsification is oneof the important mechanism of displacement. Oil recovery degree curve andpressure fluctuation state displayed the wall formation, and gradually pusheddeeply.