ERE Autumn Seminar Series-Kristian Jessen
Kristian Jessen | USC
Compositional Modeling and Simulation at Lab and Field Scale.
In order to estimate the potential incremental hydrocarbon recovery by CO2 injection, compositional reservoir simulators are commonly used in the industry. Successful design and implementation of CO2 injection processes rely, in part, on the accuracy by which the available simulation tools can represent the physics that govern the displacement behavior in a reservoir. In this work, we investigate the accuracy of some physical models that are frequently used to describe dispersive mixing and mass transfer in compositional reservoir simulation.
We use a quaternary analog fluid system (alcohol-water-hydrocarbon) that mimics the phase behavior of CO2-hydrocarbon mixtures at high pressure and temperature to study the dynamics of first-contact miscible and multicontact miscible displacement processes.
Effluent concentrations from first-contact miscible displacement experiments exhibit a tailing behavior that is attributed to imperfect sweep of the porous medium. To represent this behavior in displacement calculations, we use a dual-porosity model including mass transfer between flowing and stagnant porosities. Two 4-component two-phase displacement experiments were performed at multicontact miscible conditions and the effluent concentrations are interpreted by numerical calculations.
We demonstrate that the accuracy of our displacement calculations relative to the experimental observations is sensitive to the selected models for dispersive mixing, mass transfer between flowing and stagnant porosities, and IFT scaling of relative permeability functions. We also demonstrate that numerical calculations substantially agree with the experimental observations for some physical models with limited need for model parameter adjustment.
Inspired by our laboratory observations, we propose an upscaling technique for compositional simulation at larger scale, where a high-resolution reservoir model is transformed into a coarse dual-porosity and dual-permeability model. We introduce a streamline index to partition passive and active porosities and demonstrate that the proposed method is significantly less sensitive to coarsening than traditional single-porosity upscaling techniques.
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.