The effect of different activators on the performance of an inorganic solidifiable gel plugging fluid

This study examines a new type of inorganic gel plugging fluid that can solidify and plug into lost circulation zones. This approach resolves the difficulty of forming an effective slug in a leakage passage using a plugging agent. Difficulty forming such a slug leads to a low plugging success rate. Tests were performed to examine sample characteristics, such as the suspension stability, rheology, microstructure, and strength. Analysis of the hydration mechanism of the solidifier was performed. This study shows that activators, e.g., NaOH, Na2CO3 and Na2SiO3, can condition the rheology by changing the thickness of the hydration film of charged particles in the system. An alkaline environment can disperse the solidifier vitreum so that it dissolves and develops structures, enabling the working fluid to solidify and form plugs. Field tests at Well X demonstrate that this system can condition the additives based on actual conditions when circulation loss occurs in an oil/gas well. The pressure bearing capacity of the well increases from an equivalent circulation density (ECD) of 1.02 g/cm3-1.61 g/cm3, thus satisfying the requirements to continue drilling. The development of this system provides a new solution for the treatment of circulation loss and establishes a correlation between basic research and industrial application of the relevant materials.