Development and Application of Self-Healing Emulsion and Cement Slurry System

Abstract

In order to reduce the risk of gas channeling and improve the long-term sealing of cement sheath, a self-healing emulsion for cementing was synthesized by emulsion polymerization, and it was used as the main agent, associated with the optimized stabilizer, dispersant, fluid loss agent and retarder with good compatibility, to form a new self-healing cement slurry system. The lab tests show that through the crack seepage repair test of self-healing cement stone at normal temperature, 60 °C and 90 °C, the seepage flowrate of natural gas can be dropped to zero within 80 min at most, and the self-healing effect is obvious. The API water loss of self-healing cement slurry can be controlled within 50ml at 130 °C, the thickening time of cement slurry is short, the curve is stable, and the time is adjustable. The basic properties of cement slurry meet the requirements of field application. The permeability of self-healing cement stone is obviously lower than that of conventional cement stones, and it has strong impermeability.