Characterization of Viscous Unstable Flow in Porous Media at Pilot Scale - Application to Heavy Oil Polymer Flooding
S. Bouquet, S. Leray, F. Douarche and F. Roggero
Event name: IOR 2017 - 19th European Symposium on Improved Oil Recovery
Session: Heavy Oil
Publication date: 24 April 2017
Info: Extended abstract, PDF ( 12.96Mb )
Price: € 20
The hydrodynamic stability of polymer flooding is studied in a heavy oil context. The consistency of mobility ratio as a criterion to refer and predict the flow stability/instability is studied through numerical high resolution simulations, on a 2D pilot-scale porous medium, for different viscosity ratios between the injected fluid and fluid-in-place. Several definitions of mobility ratio are calculated, and the predictive shock mobility ratio is inferior to 1 for observed stable flow behavior and vice-versa. Whenever the flow is unstable, fingers develop, grow and tend to merge linearly with respect to the injected pore volume. Additional scenarii are studied with polymer adsorption or degradation. The unstable behavior is also analyzed when coupling flow instability and heterogeneities. The linear fingers behavior, occurring in homogeneous medium, changes with heterogeneity: fingers in-situ dynamical behavior is non-linear when channeling occurs. The less the mobility reduction is (i.e. less stable flow), the more the flow behavior is sensitive to the heterogeneities. The polymer flooding remains more efficient than waterflooding even when strong channeling occurs. Eventually, we show the consequences on water and polymer breakthrough and draw some insights about the flow behavior of a polymer injection pilot in practical cases.