超临界多元热流体提高稠油采收率机理研究

It is expected to become a transformative technology for the efficient development and utilization of offshore heavy oil for Supercritical water gasification multi-element thermal fluid thermal recovery method. In this paper, first, a supercritical Multi-Component Thermal Fluid (SCMCTF) displacement thermal core experimental system for heavy oil was developed, and then, the displacement experiments of supercritical multi-element thermal fluid (SC-MCTF) flooding, traditional Multi-Component Thermal Fluid flooding, supercritical water(SCW) flooding and highpressure hot water (HW)flooding were carried out, and different injection techniques were compared and studied, and analyzes different injection conditions oil displacement efficiency, thermal efficiency, core temperature and pressure distribution and evolution characteristics. The results show that supercritical Multi-Component Thermal Fluid(SC-MCTF) flooding has the multiple characteristics of thermal flooding, gas flooding and miscible flooding, significantly improve the oil displacement efficiency, oil recovery rate and thermal efficiency, moreover,it can suppress the steam and supercritical water override phenomenon, and expand the scope of the spread. Compared with supercritical water flooding (25 MPa, 400℃), the oil displacement efficiency of supercritical Multi- Component Thermal Fluid(SC-MCTF) flooding (25 MPa, 400℃) is as high as 95%, and the oil displacement efficiency is increased by 3%, the oil recovery rate is increased by 47%, and the thermal efficiency is improved 16%.