A review of SAGD technology development and its possible application potential on thin-layer super-heavy oil reservoirs

Super-heavy oil is a significant unconventional energy source, and more than 30 years of research have shown that steam-assisted gravity drainage (SAGD) technology is suitable for thick super-heavy oil reservoirs. Recently, more and more thin-layer super-heavy oil reservoirs have been discovered in China, while their deep buried depth and serous heterogeneity make the existing SAGD technology difficult to apply, so it is urgent to improve the existing SAGD technology for the thin-layer super-heavy oil. To this end, this paper focuses on the enlightenment of field application in SAGD technology. Firstly, based on typical SAGD field projects, the development history of SAGD technology in the world was reviewed, and the influence of reservoir physical properties on the application of SAGD technology in thin-layer super-heavy oil reservoirs was analyzed. Secondly, the well pattern, wellbore structure, pre-heating, artificial lift, and monitor technique of SAGD were detailed described, and their adjustment direction was expounded for the development of thin-layer super-heavy oil reservoirs. Lastly, the gas- and solvent-assistant SAGD were comprehensively evaluated, and their application potential in thin-layer super-heavy oil reservoirs was studied. The research results can provide theoretical guidance for the application of SAGD technology in thin-layer super-heavy oil reservoirs.