In this work, the powder injection process at the bottom of the converter was numerically simulated by establishing a coupled gas-liquid-solid mathematical model. The effects of powder injection speed, solidgas ratio, particle size, and injection position on the trajectory and residence time of particles in the molten pool are studied. The discrete phase and continuous phase coupling solution method is used to analyze the change of the molten pool flow field after powder injection. It is found that increasing the spraying rate can reduce the particle concentration near the liquid surface from 2.3 kg/m 3 to 1.18 kg/m 3 . Increasing the solid-gas ratio from 10 kg/m 3 to 30 kg/m 3 can increase the powder distribution ratio from 70.9% to 93.1%. The larger the size of the particles, the easier it is to stay near the liquid level, and the maximum can reach 2.13 kg/m 3 . Finally, it was also found that spraying powder at 0.7 R can make the powder more uniformly distributed in the molten pool.

Herein, a converter model is established to study the powder spraying process. The effects of powder spraying speed, solid–gas ratio, particle size, and powder spraying position on the distribution of powder in a molten bath and the molten iron splash on a liquid surface are quantitatively studied by using image technology. Increasing the carrier gas flow to 2 m3 h−1 can effectively promote the movement and mixing of the powder in the molten bath, but at the same time, this leads to a degree of splash of 50.61% above the molten bath. A similar situation occurs with increasing solid–gas ratio and decreasing particle size. However, as the powder injection position is gradually moved away from the center of the furnace bottom, the powder distribution before 3 s is more advantageous, and the degree of splash decreases from 25.39 to 12.40%.

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