HPAM-Cr (III) Gel Syneresis in Bulk Volume

Abstract

This paper explores the crucial factors influencing the stability of polymer gels utilized in oil well treatments, with a focus on the effects of polymer mixing time and concentrations of polymer and crosslinker. Operating within a practical constraint of a 30-minute mixing time in surface facilities, our findings reveal that incomplete polymer dissolution leads to gel segregation and substantial water release over extended aging at 50 ºC. Notably, a reduction in the crosslinker/ polymer ratio, achieved by lowering crosslinker concentration or increasing polymer concentration, proves effective in mitigating water release to as low as 0‒1% over 90‒185 h of aging. Furthermore, gels prepared in sea and reservoir brines exhibit superior stability compared to those in distilled water, suggesting that ion presence in brines counteracts the repulsion between charged polymer chains observed in distilled water. This study provides valuable insights for optimizing polymer gel formulations under time constraints.