Flow Behavior of Nanoparticle Stabilized Drilling Fluids and Effect of High Temperature Aging

Nanoclay and nanosilica were used to stabilize invert emulsion model drilling fluids for HTHP application. Though each nanomaterial can stabilize the emulsion by itself, best properties were obtained when both were used. Yield stress and plastic viscosity were found to be dependent on composition and the hydrophobic/hydrophilic nature of the nanoparticles. Adding barite results in loss of yield stress, however, it can be regained by increasing the nanosilica content. Aging at 225 o C (437 o F) for 96 hrs showed that the nanoparticle stabilized emulsions remain stable with only small changes in rheological properties.