An Experimental Study Comparing The Stability Of Colloidal Dispersion Gels With Normal Polymeric Solutions For Enhanced-Oil-Recovery Purposes

Waterflooding in oil reservoirs is associated with several drawbacks. Recently, colloidal dispersion gels (CDG) have been proposed as a new method for conformance control to address these drawbacks. CDGs are prepared by mixing crosslinkers and polymers in very low concentrations as a result of intramolecular crosslinking. In this research, a comprehensive study was conducted on the stability of sulfonated polyacrylamide (SPAM) solutions and CDGs prepared using the same SPAM in harsh conditions. The effects of high temperature, shear rate, salts, and high mechanical degrading on the viscosity of both polymeric solution types were studied using a rheometer. The results showed that, in similar conditions, CDGs are less susceptible to salts than are normal SPAM solutions. Moreover, both solutions have nearly the same sensitivity to temperature. The effect of extremely high shear rates was also studied, and the results suggested that, in similar conditions, CDG is less susceptible to high shear rates than normal SPAM solutions. Being treated at 2500 1/s for 2 hours, the CDG solution lost almost 0% of its original viscosity, while the SPAM solution lost 0.97% of its original viscosity. Given that CDG is more stable in harsh reservoir conditions, it may be a suitable substitute to the highly sensitive polymeric solutions for improving the volumetric sweep efficiency of waterfloods.