Activated desorption at heterogeneous interfaces and long-time kinetics of hydrocarbon recovery from nanoporous media.
Hydrocarbon recovery from unconventional reservoirs (shale gas) is debated due to its environmental impact and uncertainties on its predictability. But a lack of scientific knowledge impedes the proposal of reliable alternatives. The requirement of hydrofracking, fast recovery decay and ultra-low permeability-inherent to their nanoporosity-are specificities of these reservoirs, which challenge existing frameworks. Here we use molecular simulation and statistical models to show that recovery is hampered by interfacial effects at the wet kerogen surface. Recovery is shown to be thermally activated with an energy barrier modelled from the interface wetting properties. We build a statistical model of the recovery kinetics with a two-regime decline that is consistent with published data: a short time decay, consistent with Darcy description, followed by a fast algebraic decay resulting from increasingly unreachable energy barriers. Replacing water by CO2 or propane eliminates the barriers, therefore raising hopes for clean/efficient recovery.
MultiScale Materials Science for Energy and Environment, Joint CNRS-MIT Laboratory, UMI CNRS 3466, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.|Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Thomas
0000-0002-8261-0181
T
Lee
MultiScale Materials Science for Energy and Environment, Joint CNRS-MIT Laboratory, UMI CNRS 3466, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.|Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.|Laboratoire de Physique Statistique, UMR CNRS 8550, Ecole Normale Supérieure, 75005 Paris, France.
Lydéric
L
Bocquet
MultiScale Materials Science for Energy and Environment, Joint CNRS-MIT Laboratory, UMI CNRS 3466, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.|Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.|Laboratoire Interdisciplinaire de Physique, CNRS and Université Grenoble Alpes, UMR CNRS 5588, 38000 Grenoble, France.
Benoit
B
Coasne