Utilization of mesoporous nano-silica as high-temperature water-based drilling fluids additive: Insights into the fluid loss reduction and shale stabilization potential

Abstract

Optimally performing drilling fluids play a vital role in drilling operations. The demand for thermally stable drilling fluid in the oil and gas sector necessitates using advanced additives to create suitable formulations. This research study introduces the novel application of Mesoporous Nano-Silica (MNS) to enhance water-based drilling fluid's inhibitive, rheological, and fluid loss characteristics. MNS was synthesized by the sol-gel technique with Cetyltrimethylammonium Bromide (CTAB) for generating the pores. The hydrodynamic particle size of the synthesized MNS was 134.47 nm with a stable zeta potential of −32.2 meV. Brunauer-Emmett-Teller (BET) analyzer estimated the specific surface area to be 626 m2/g and the pore volume to be 0.3415 cm3/g. A comparative analysis of the drilling fluid properties is presented in which MNS was added to the fixed base formulation at varied concentrations (0.05, 0.1, 0.2, 0.5, and 1 wt%). Samples were subjected to hot rolling at 180 °C temperatures at 100 psi pressure for 16 h, evaluating the influence of thermal aging on the properties of the drilling fluid. The viscometric investigation was performed at 25 and 70 °C while the inhibitive properties were checked via shale recovery test and capillary suction timer. The filtration properties were examined at 100 psi and 500 psi pressure at 150 °C. The experimental findings reveal that MNS can substantially improve the thermal properties of water-based drilling fluids, maintaining rheological characteristics and drastically reducing fluid loss while imparting some inhibitive properties. Interestingly, after hot rolling the plastic viscosity of MNS-infused mud was 77% better than that of the base mud. Incorporating macro-sized particles and MNS nanoparticles into water-based drilling fluids can enhance its rheological properties, reduce filtrate loss, and improve shale inhibition characteristics which may be attributed to either the size effect or the synergistic influence of materials. Therefore, including MNS as a high-performance additive may contribute to advancing drilling operations in the petroleum industry, offering valuable insights for optimizing drilling fluid formulations.