Adsorption behavior of silica nanofluid on coal and its injection enhancement mechanism

Coal seam water injection has proven effective in mitigating coal and gas outburst disasters in mines. However, its drawbacks, including the poor wettability of coal seams and the susceptibility to filtration loss of injected water, have led to low construction efficiency and uneven control outcomes. In this study, we propose a novel approach to address these issues by utilizing a water-based silica nanofluid to alter surface wettability. The four-stage deposition process of nanoparticles on the coal surface is identified, and the time-varying behaviour of modified coal wettability is revealed under the influence of key parameters, such as particle concentration. These findings provide a foundation for the application of nanofluids in modifying the wettability of reservoirs.