Preparation and application of a glucose graft copolyammonium as shale inhibitor

Abstract

In the paper, a shale inhibitor, glucose graft copolyammonium (GGPA), was prepared and evaluated by bentonite linear expansion test, anti-swelling experiments, mud ball experiments. The drilling fluid properties were evaluated. Anti-swelling results shows that anti-swelling rate of 0.8% GGPA reaches up to 94.5%. Mud ball experiment and drilling fluid evaluation showed that GGPA has strong inhibitive capability to bentonite hydration swelling. GGPA can control the particle size of bentonite. The inhibition mechanism of the polyamine salt was analyzed by thermogravimetric analysis and scanning electron microscope. The results demonstrate that the GGPA can be adsorbed on clay surface through electrostatic interaction and hydrogen bonds by an anchoring effect and a hydrophobic effect.