Evaluation of Viscoelastic Behavior during Surfactant-polymer Flooding in Porous Media Using Microfluidics
R.R. Elhajjaji, R.E. Hincapie and L. Ganzer
Event name: 78th EAGE Conference and Exhibition 2016
Session: Improved Oil Recovery
Publication date: 31 May 2016
Info: Extended abstract, PDF ( 1.29Mb )
Price: € 20
This evaluation includes laboratory experiments, analysis, and comparison that lead to the understanding of viscoelastic behavior in porous media when polymer and surfactant flooding are applied in combination. We use a microfluidic device that has a hyperbolical contraction-expansion geometry, in which pressure drops are recorded across the contraction zone and to resemble the porous media. Pressure drops at the contraction zone are analyzed to exclude the shear contribution from the measured apparent extensional viscosity, by applying a predefined correction procedure. This analysis investigates the impact of pressure changes, solution concentrations and different solvents on the displacement process. Variables such as interstitial velocity and pressures caused by the pore throat have been selected and primarily considered to be equivalent to reservoir flow conditions during the injection process. As a result of different extensional and dynamic viscosity measurements, Surfactant-Polymer mixtures showed a pseudo-plastic behavior with an incremental ratio of viscosity by 20%. Furthermore, at interstitial reservoir velocities, the mixtures exhibited a high increase in pressure drops and Normal Stress Differences (N1) which describe elasticity during flow, and that can be attributed either to extensional effects or molecules agglomeration. Pressure changes suggested that viscoelastic properties are improved by using a Surfactant-Polymer combination.