Research Projects

The demand for efficient and sustainable oil extraction has motivated researchers to look for novel ‘enhanced oil recovery (EOR)’ techniques. Among various EOR methods, polymer flooding has gained significant attention for its effectiveness. Polymeric solutions improve oil recovery by increasing the viscosity of the injected water, thereby reducing the water-to-oil mobility ratio and enhancing volumetric sweep efficiency. In addition, the polymer solutions exhibit viscoelastic behavior, which gives rise to unique microscale mechanisms, such as pulling, tugging, and stripping, leading to displacement of the residual oil trapped within porous rock structure. However, polymer flooding often creates stable water-in-oil emulsions that are hard to separate, thereby slowing down production and incurring additional cost. While various demulsification techniques have been studied, electrocoalescence facilitates droplet deformation and coalescence, enhancing separation in polymer-stabilized emulsions. Research on electrically-assisted manipulation of droplets (EHD) was primarily confined to lab-on-a-chip and biomedical contexts. While electrocoalescence has been employed for crude oil dehydration, its behaviour within viscoelastic, multiphase environments at the microscale, where droplet deformation, interfacial forces, and electrohydrodynamic stresses dominate, remains poorly understood. Moreover, the application of droplet-based microfluidics to investigate electrocoalescence in reservoir-relevant conditions has not been reported in the literature. Hence, there is a considerable gap in research on the potential advantages of the electro-viscoelastic instability in EOR. To test the hypothesis about the role of electro-viscoelastic instability in demulsification, the present project aims to develop a droplet microfluidics platform accompanied by numerical simulations. The specific objectives will be: (1) Quantifying how polymer viscoelasticity alters droplet generation modes and size distributions under electrical forcing; (2) Tracking droplet trajectories and deformation in a confined, pressure-driven flow with DC and AC fields, and subsequently demonstrating whether electric forces overcome (or cooperate with) viscoelastic migration effects. This information will also help us delineate how the field-mediated transport of droplets can be optimized to focus towards coalescence zones. (3) Trapping the crude oil-polymer emulsion to a single, transparent microfluidic layer and systematically varying the field type (DC vs. AC), field strength and frequency, electrode geometry, and polymer concentration. This will enable us to identify the best conditions that maximize coalescence efficiency. (4) Finally, we will implement the optimized conditions in a porous microchannel network, also known as `reservoir-on-a-chip', which will mimic a microporous network in oil reservoirs. The high-resolution data regarding liquid front propagation can be recorded, which would help us understand the ways to increase sweep efficiency and mitigate events like viscous fingering and droplet fragmentation in a lab-scale reservoir scenario. The project will not only develop fundamental understanding at the pore scale but also build a practical device prototype (ROC) for harnessing electro-viscoelastic phenomena to improve oil recovery and demulsification processes. The proposed lab-scale setup will lead to a fast, cost-effective way to evaluate EOR strategies. It has strong potential to attract public and private entities (e.g. ONGC, Cairn Oil & Gas, etc.) aiming to benefit from India's updated EOR policy. With industry collaboration, the findings can be scaled up to pilot-level studies and potentially deployed in real oil fields. In addition, the proposed method of electrical demulsification for polymer flooding offers a greener alternative to conventional thermal or gas injection techniques, thereby contributing to environmentally sustainable oil recovery.