Apparent permeability of liquid rich shales

The goal of this research is to present a new formulation expressing the apparent permeability of liquid rich shale strata based on pressure driven flow. Apparent permeability is important for the accurate prediction of production rates.;For the first time we introduce an apparent permeability formulation to predict the volumetric flux of oil in liquid rich shale formations. Nanopores associated with the structure of shale formations introduce molecular slippage on the pore walls and break down the continuum no-slip flow assumption. The molecular slippage on the pore walls makes Darcy's permeability inappropriate to determine the volumetric flux of oil in shale formations.;In this research, a correction to the slippage phenomenon is made to properly model fluid flow in shale oil strata. The proposed permeability expression is validated with an existing set of experimental data. The derived formulation in this study shows that the apparent permeability of liquid rich shales increases with increased slip length; the slip length is defined as an extrapolated distance relative to the nanopore wall where the tangential velocity component vanishes. This novel permeability formulation is expressed in a compatible form with Darcy's equation for ease of use in reservoir simulators. The results suggest that the proposed apparent permeability term provides a better prediction of oil volumetric flux compared to that given by the simple Darcy's permeability.