Study of the modification of in-depth relative permeability modifier (RPM) by graft zeolite copolymers for conformance control

Abstract

The most used technique for controlling high water production in mature oil fields is conformance control agent with high swelling behavior and stability. However, conformance control destabilization often occurs from particle aggregation leading to particle migration (creaming or sedimentation). Coalescence or cluster formation at an early stage of conformance control is crucial for increasing thermal stability and enhancing formulations. The objective of this study was to characterize the colloidal dispersion stability of grafted zeolite copolymers to assess its use as potential conformance control in carbonate reservoirs. In this study, grafting form of bentonite, acrylamide (AM), 2-acrylamino-2-methylpropanesulfonic acid (AMPS), zeolites with anionic surfactants (Sodium Dodecyl Sulphate, SDS) and nonionic surfactants (Span 80 and Tween 80) were prepared. Stability during multiple light scattering analysis of grafted bentonite with and without modification were observed and compared through Turbiscan Classic MA 2000. The results revealed that the multiple light scattering analysis and colloidal dispersion stability all reflect the stability system of the grafted bentonite. Indeed, the multiple light scattering analysis was able to be used to derive the stability for graft zeolite copolymers and showed good agreement with the results from turbidity. The addition of zeolites combined with Span 80 and Tween 80 was observed to enhance stability, maintaining a 1% transmission value over 60 minutes, which is classified as having “good” characteristics for conformance control.