Experimental, modeling and simulation investigations of a novel surfmer-co-poly acrylates crosslinked hydrogels for water shut-off and improved oil recovery

Abstract

Abstract Nowadays, chemical and petroleum engineers give incremental attention to different techniques of chemical enhanced oil recovery (CEOR) owing to continual and scared energy consumption, and enormous trapped oil reserves after primary and secondary flooding. Hydrogels are three-dimensional crosslinked macromolecules which retain excessive water amounts. In this research, we investigate the synthesis and spectroscopic characterization of Lutensol AT 25 E -Methacrylate surfmer, then its copolymerization with acrylates monomers through free radical polymerization, which considered an effective tool to generate block copolymers with hydrophilic and hydrophobic moieties. Characterization and structure determination occurs by traditional spectroscopic techniques. Since mathematical formulation and prediction of hydrogel swelling ability has incremental consideration recently, so mathematical modeling of different rheological properties including swelling performance, post-degraded gel viscosity, gel strength, viscoelastic properties as well as shear thinning effects, salinity resistance, and long-term thermal aging was investigated at simulated harsh reservoir conditions. Modeling analysis showed that the Herschel-Bulkley model fits effectively the stress performance of the hydrogel suspensions, while the power law model fits the viscosity-shearing behavior. Dynamic properties examined by oscillatory tests indicating that hydrogel suspension exhibits viscoelastic performance since elastic modulus (G′) predominate viscous modulus (G″). On lab scale, sandpack flooding tests performed on a linear assembly at imitated reservoir environment, where the results indicate that the hydrogel able to reduce water permeability, adjust profile conformance, so increase incremental oil recovery up to 85.35% and alter rock wettability which assessed through relative permeability curves at different water saturation. On a field scale, a simulated run on actual reservoir data written by Fortran 90 visual studio carried out through UTCHEM software to evaluate hydrogel compatibility as an enhanced oil recovery candidate.