Preparation and application of a novel polyammonium as potent shale hydration inhibitor

Abstract

In this paper, a novel shale hydration inhibitor polyammonium abbreviated as DEP was prepared by piperazine, epichlorohydrin and dimethylamine, and evaluated by anti-swelling experiments, linear expansion tests, mud ball experiments, hot rolling tests and particle size experiments. Anti-swelling results showed that anti-swelling rate of DEP-7 have reached up to 86.30% when its concentration was 0.8 wt%. Mud ball experiments showed that the polyammonium has strong inhibition ability to inhibit bentonite hydration swelling and control the particle size of bentonite. Thermo gravimetric analysis and scanning electron microscope was used to study its inhibition mechanism. Results demonstrated that DEP-7 can be adsorbed on clay surface through electrostatic interaction and hydrogen bonds by anchoring effect and hydrophobic effect.