Laboratory Evaluation of High-Temperature Conformance olymer Systems

Abstract

Abstract This paper presents the results of laboratory evaluation regarding the effectiveness of novel, organically crosslinked, high-temperature, conformance polymer gel systems as sealants. Effectiveness of these sealant gels is evaluated by attempting water flow through high-permeability cores under residual oil conditions. The effectiveness of the sealants to (1) block water permeability at temperatures up to 350°F, (2) provide long-term sealant properties at these temperatures, and (3)provide adequate gel time for placement is measured. The ultimate goal is to determine whether the selected crosslinked polymer systems provide useable extended gel times and maintain thermal stability to 350°F. Discussed are (1) the physical laboratory model and test conditions used to perform dynamic core flow studies over extended periods in determining the impact of sealant exposure to elevated temperatures and subsequent required modifications, (2) experimental procedure used for dynamic core flow studies, (3) the effect of temperature on permeability reduction over time, (4) the impact of threshold pressure (differential pressure required before fluid flow begins through a treated core) on permeability reduction over time, (5) laboratory methodology used for gelation time measurement of a new, novel, organically crosslinked, high-temperature, conformance polymer gel system, and (6) laboratory results regarding gelation time of the polymer system as a function of temperature up to 350°F.