Flow, Heat-Transfer, and Mixing Behaviors of Scrap Steel in a Refining Ladle with Bottom Blowing

The flow, heat-transfer, and mixing behaviors of steel scraps with different amounts, positions, and sizes added from the top of the bottom-blown 300 t ladle are numerically investigated and compared through a coupled model. In the results, it is shown that it takes 59 s to mix the temperature of molten steel after adding scrap steel at the position of x = 0 mm, y = 553.5 mm, and z = 3375 mm. The further the addition position is from the axial position of the permeable brick, the shorter the mixing time of the speed and temperature of molten steel. For the scrap amount of 0.5, 1.5, and 2.5 t, the mixing time of molten steel temperature is 44, 78, and 47 s, correspondingly, which exhibits a pattern of initial increase followed by decrease, with an ≈8 K decline in molten steel temperature for every additional 1.0 t of scrap. When considering the scrap size of 10, 30, and 50 mm, the average temperature mixing time of molten steel is 44, 61, and 45 s, respectively. In this research, theoretical guidance can be can be provided for the addition of scrap in ladle during practical production processes.