Fully compositional and thermal reservoir simulation

• We present a new approach for fully compositional and thermal reservoir simulation.
• We raise reservoir simulation awareness in process systems engineering.
• Models consist of rigorous mass and energy balances for reservoirs and wells.
• Flash efficiency is improved using compositional space adaptive tabulation (CSAT).
• Two EOR applications clearly show our new approach is reliable and efficient.

Fully compositional and thermal reservoir simulation capabilities are important in oil exploration and production. There are significant resources in existing wells and in heavy oil, oil sands, and deep-water reservoirs. This article has two main goals: (1) to clearly identify chemical engineering sub-problems within reservoir simulation that the PSE community can potentially make contributions to and (2) to describe a new computational framework for fully compositional and thermal reservoir simulation based on a combination of the Automatic Differentiation-General Purpose Research Simulator (AD-GPRS) and the multiphase equilibrium flash library (GFLASH). Numerical results for several chemical engineering sub-problems and reservoir simulations for two EOR applications are presented. Reservoir simulation results clearly show that the Solvent Thermal Resources Innovation Process (STRIP) outperforms conventional steam injection using two important metrics – sweep efficiency and oil recovery.