Overview of thermal concepts in enhanced oil recovery

Fractal Pore-Scale Model for Effective Thermal Conductivity of Multiscale Unsaturated Porous Media

“…Water-based enhanced oil recovery (EOR) techniques have been proven profitable in conventional reservoirs for decades; however, the extremely low permeability and mixed wettability of unconventional formations present foremost obstacles to success. , Meanwhile, thermally enhanced oil recovery (TEOR) techniques use thermal energy from hot fluid injection, in situ combustion, and electrical and electromagnetic heating to reduce oil viscosity, specific gravity, and interfacial tension, which facilitate oil flow in the production well . TEOR is a highly promising EOR method in the development of unconventional hydrocarbon resources including heavy oil, shale oil and gas, coal bed methane, etc. − Heat conduction is pivotal in designing of TEOR systems, where the estimation of thermal conductivity of unconventional formations becomes significant . However, the multiscale structures of unconventional formations may range from macro- to micro- and even nanosize, and the multiphase media usually include oil, gas, liquid, and solid.…”

“…4−7 Heat conduction is pivotal in designing of TEOR systems, where the estimation of thermal conductivity of unconventional formations becomes significant. 8 However, the multiscale structures of unconventional formations may range from macro-to micro-and even nanosize, and the multiphase media usually include oil, gas, liquid, and solid. Thus, the multiscale structure and multiphase media have important influences on the TEOR processes 9 and challenge the prediction of thermal conductivity of unconventional reservoirs.…”