Laboratory and theoretical evaluation of gelation time data for water-based polymer systems for water control

This article presents the evaluation and modeling of gelation-time data generated for four different water-based polymer systems used in the oil industry as sealants to shut off the undesired water production from hydrocarbon reservoirs. This article focuses primarily on the measurement and analysis of gelation time provided by each system at different temperature ranges. Each system presented in this article exhibits a different gelation mechanism. Gelation time for each system was measured as a function of temperature, activator concentration, polymer concentration, crosslinker concentration, salinity percent of mixing brine, and/or pH of solution. Methodologies used for gelation-time measurement and laboratory results are discussed. This article presents an investigation of temperature dependence of gelation time for each system that was analyzed and successfully correlated using an Arrhenius-type equation. The analysis of gelation-time data using the Arrhenius-type equation reveals and confirms the different gelation mechanisms working among the systems.