Numerical and Economical Investigations on Thermal Enhanced Oil Recovery Techniques

Abstract

The exploitation of heavy and extra-heavy oil reserves is unavoidable in order to meet global energy demand growth. Viscosity and mobility properties adversely affect the sweeping of oil toward the wellbore. As a result, the reservoir’s primary resource remains untapped or as residual oil in the reservoir's pore spaces. Nonetheless, in-situ thermal oil recovery techniques are efficient and cost-effective for producing heavy oil reservoirs. The oil recovery factor varies between 10–15% during the primary production stage. This means that over 85% of the OOIP (original oil in place) remains underground once the process begins. At this point, the selection and design of thermal recovery methods become critical for continued well production. A reservoir simulation study is used to predict the recovery by thermal EOR process for heavy oil reservoirs in this case. CMG software was used to conduct a detailed simulation study for various oil viscosity types, including heavy oil with a viscosity of 120 cP and extra heavy oil with a viscosity of 1730 cP. The sensitivity of crucial factors that significantly affect well performance is investigated. An economic analysis of each recovery technique was also conducted to determine its commercial viability. The presented results emphasize the importance of comparing cumulative oil production, oil recovery factor, and economic feasibility when determining suitable and effective recovery techniques. The article primarily determines the optimal recovery technique for producing heavy oil reservoirs.