Evaluation of the Dynamic Interfacial Tension between Viscoelastic Surfactant Solutions and Oil Using Porous Micromodels

Abstract

Interfacial tension (IFT) is a crucial parameter in many natural and industrial processes, such as enhanced oil recovery and subsurface energy storage. IFT determines how easy the fluids can pass through pore throats and hence will decide how much residual fluids will be left behind. Here, we use a porous glass micromodel to investigate the dynamic IFT between oil and Armovis viscoelastic surfactant (VES) solution based on the concept of drop deformation while passing through a pore throat. Three different concentrations of VES, that is, 0.5, 0.75, and 1.25% vol% prepared using 57 K ppm synthetic seawater, were used in this study. The rheology obtained using a rheometer at ambient temperature showed zero shear viscosity of 325, 1101, and 1953 cP for 0.5%, 0.75%, and 1.25% VES, respectively, with a power-law region between 2 and 50 1/s. The dynamic IFT increases with the shear rate and then reaches a plateau. The results of IFT were compared with those obtained from the spinning drop method, which shows 97% accuracy for 1.25% VES, whereas the accuracy decreased to 65% for 0.75 VES and 51% for 0.5% VES. The findings indicate that we can reliably estimate the IFT of VES at higher concentrations directly during multiphase flow in porous micromodels without the need to perform separate experiments and wait for a long time to reach equilibrium.

Investigating Effects of Chelating Agents on Viscoelastic Surfactant Flooding at the Pore Scale Using Micromodels

“…The viscosity ratio is calculated at the specific shear rate from the rheology profile. The calculation steps are explained in the equations below u = L t 2 − t 1 γ̇ = u d D = a − b a + b D = 19 λ + 16 16 λ + 16 C a λ = μ normald μ normalc C a = γ̇ R μ normalc σ σ = γ̇ R μ normalc D 16 λ + 16 19 λ + 16 where u is the droplet speed from the initial to final position (mm/s), L is the distance between the initial and final droplet position (mm), t 1 and t 2 are the times at each position (s), a and b are the major and minor axes of the elliptical droplet shape, D is the drop deformation factor, d is the distance between the droplet center and capillary boundary (mm), γ̇ is the shear rate (s –1 ), λ is the viscosity ratio of the dispersed phase to continuous phase, Ca is the capillary number, and σ is the IFT (mN/m).…”

“…The viscosity ratio is calculated at the specific shear rate from the rheology profile. The calculation steps are explained in the equations below 59 = u L t t 2 1…”

“…Microfluidic setup consisted of a micro syringe pump, a high-speed microscope, a glass micromodel with a base, pressure transducers, and a computer for control and data recording. This figure was reproduced with permission from ref . Copyright 2022 American Chemical Society.…”

“…57,58 We further enhanced that application and estimated the dynamic IFT for regular geometry in normal surfactant flooding without the need to prepare emulsions outside because the emulsion forms during the flooding. 59 In this study, we will do a rigorous study on the use of glutamic acid diacetic acid (GLDA) and diethylenetriaminepentaacetic acid (DTPA) to enhance the properties of VES in terms of rheology and IFT and quantify their complex effect on enhancing recovery compared to pure VES. We will also estimate the dynamic IFT while flooding in real geometry using Tylor's theory and link it to the oil recovery.…”

“…D’Apolito et al used Taylor’s deformation concept , to analyze the injected drops that have been formed in an emulsion prepared outside the micromodel and obtained the dynamic IFT values. Their method does not need any special geometry to form the drop as used in previous studies like T- and Y-junction geometries. , We further enhanced that application and estimated the dynamic IFT for regular geometry in normal surfactant flooding without the need to prepare emulsions outside because the emulsion forms during the flooding …”