Experimental investigation of enhanced oil recovery and in-situ upgrading of heavy oil via CO2- and N2-assisted supercritical water flooding. (15th March 2023)

• Record Type: Journal Article
• Authors: Huang, Zujie; Zhao, Qiuyang; Chen, Lei; Guo, Liejin; Miao, Yan; Wang, Yechun; Jin, Hui
• Is Part Of: Chemical engineering science. Volume 268(2023)
• Publication Date: 2023-03-15
• Subjects: Heavy oil -- Enhanced oil recovery -- In situ upgrading -- Gravity override -- Emulsion; Chemical engineering -- Periodicals; Génie chimique -- Périodiques; Chemical engineering; Periodicals; Electronic journals; 660
• DOI: 10.1016/j.ces.2022.118378
• Languages: English
• ISSNs: 0009-2509

Abstract

Highlights: SCW/CO2 /N2 mixture injection is proposed for heavy oil recovery. A core experimental system of SCW/CO2 /N2 flooding is developed. SCW/CO2 /N2 flooding is divided into three stages. CO2 and N2 provide the driving force and eliminate gravity override. SCW/CO2 /N2 flooding can both enhance oil recovery and upgrade oil quality. Abstract: Exploitation of heavy oil is critical for mitigating the energy crisis. However, conventional thermal recovery methods cannot completely exploit the potential of heavy oil owing to its high viscosity and heavy distillates. A new technology is proposed with reference to CO2 – and N2 -assisted supercritical water (MGA-SCW) injection for heavy oil recovery. In this study, an experimental apparatus was developed to simulate the MGA-SCW flooding process and test its feasibility. MGA-SCW injection remarkably enhanced oil recovery, increased the oil production rate, and improved the oil quality. For MGA-SCW flooding at 25 MPa and 400 °C, the recovery factor approached 95 %, and the oil viscosity decreased by 32 %; the light distillate fraction (180–350 °C) increased from 11 to 15 %. The dynamic process of MGA-SCW flooding is divided into three stages: pressure difference, thermal, and miscible drives. This technology can be applied to the development and utilization of offshore heavy oil fields.