Abstract: For air casing drilling construction process, optimizing the optimal process parameters of casing drilling, based on pulverized coal particle migration and computational fluid dynamics, the paper analyzes the influence of air supply parameters, drilling speed, drilling rate, drilling process parameters on slag in the process of drilling of air casing. Through numerical simulation and image display, the drilling ring empty section of pulverized coal particles of the highest volume fraction and particle minimum velocity are used as evaluation standard of slag discharge effect, we quantitatively describe the volume fraction of pulverized coal of different process parameters, and obtain the technological parameters in the process of discharging effect of drilling.