A Laboratory Investigation of Viscosified CO2 Process

Abstract

ABSTRACT Supercritical CO2 was thickened using a commercial silicon polymer and toluene as cosolvent. The pressure range for polymer solubility in CO2 was determined, and the viscosity of the thickened CO2 measured. The viscosified CO2, increased by two orders of magnitude in viscosity, was used in corefloods in Berea and carbonate reservoir cores. The oil recovery obtained with the viscous CO2 was compared with the results obtained using neat CO2, WAG(1:1), and CO2 with a cosolvent without a polymer. The results show clearly that oil recovery is enhanced and CO2 breakthrough retarded significantly with viscosified CO2.