Events

Speaker:  Dr. Kristian Jessen, Associate Professor in the Mork Family Department of Chemical Engineering and Materials Science at University of Southern California

Title of Seminar: “Equilibrium and Mass Transfer Considerations in Fractured Reservoirs”

Abstract: In this talk, we present a dual-porosity model in which the generalized Fick’s law is used for molecular diffusion to account for the dragging effects; and gas-oil diffusion at the fracture-matrix interface is modeled based on film theory in which the gas in fracture and oil in the matrix are assumed to be at equilibrium. Diffusion coefficients are calculated using the Maxwell-Stefan model and are pressure, temperature and composition dependent.

We compare our proposed approach with conventional models using several field-scale examples with different values of key parameters such as matrix permeability, fracture spacing and reservoir pressure. We demonstrate that the dragging effects (off-diagonal diffusion coefficients) can impact the oil recovery during gas injection in fractured reservoirs significantly. We also demonstrate that using proper physical models for matrix-fracture interactions (e.g. film theory) can considerably affect the simulation results as compared to conventional models.  

Finally, we address the impact of fluid confinement on equilibrium and mass transfer in dual-porosity systems in the context of enhanced recovery from unconventional resources.

Biography:  Kristian Jessen is Associate Professor in the Mork Family Department of Chemical Engineering and Materials Science at University of Southern California. He holds BSc, MSc and PhD degrees in Chemical Engineering from the Technical University of Denmark. Dr. Jessen is the co-founder of the consulting company Tie-Line technology ApS that specializes in PVT software for design and optimization of gas injection processes. He has authored and co-authored numerous technical papers in the area of modeling and simulation of enhanced oil/gas recovery by gas injection processes. His current research activities also include characterization and modeling of mass transfer and sorption phenomena in the context of unconventional oil and gas resources.