Effect of HMP-C16AM on Enhancing Heavy Oil Recovery by Emulsification

The hydrophobically modified polymer with N-hexadecylacrylamide (C(16)AM) as hydrophobic group (HMP-C(16)AM) is the most widely used polymeric emulsifier in oil fields. Given its amphiphilic property, aqueous HMP-C(16)AM solution can form a stable emulsion with the oil phase under the action of shear force. In this study, we investigated the emulsifying property of HMP-C(16)AM for heavy oil from multiple angles. First, the properties of the heavy oil emulsion using HMP-C(16)AM were studied under different conditions. Second, a glass-etched visual micromodel was further applied to study the emulsification of heavy oil in the pore throat during the HMP-C(16)AM flooding. Results showed that the increased stability of the heavy oil emulsion resulted in the small average particle size of oil droplets and increased the viscosity and the viscoelasticity. The combined system of low-salinity water and HMP-C(16)AM improved the stability of the heavy oil emulsion. As shown by the microscopic oil displacement test, the heavy oil was emulsified in the pore throat, and the heavy oil recovery was enhanced remarkably in the outlet and edge regions of the micromodel after the HMP-C(16)AM flooding. The study provides theoretical guidance for the next field experiment.