The Effect of Flow Rate on the In-Situ Gelation of a Chrome/Redox/Polyacrylamide System

Abstract
Summary: This paper presents experimental data on the gelation of a polyacrylamide/thiourea/Cr(VI) gel system in unconsolidated sandpacks at flow rates typical of those encountered beyond the immediate vicinity of a wellbore. At these low rates, in-situ gelation during flow was characterized by an abrupt increase in flow resistance that occurred over a short distance at a specific location along the sandpack. The location of this region was a function of flow rate, and its distance from the inlet increased as flow rate increased. Filtration of gel aggregates appears to be the mechanism causing this behavior.