Numerical Study of the Bubble Behavior of a Ladle with Different Purging Plug Designs

Abstract

Ladle refining is widely applied to satisfy the demand for high-quality steel. A purging plug, a key component of ladle refining, is used for blowing argon into the molten steel to form upward-moving bubbles that drive the molten steel in a circular flow. [1][2][3] The circular flow carries inclusions to the slag layer. These inclusions are then adhered to the slag to remove them. [4,5] Meanwhile, nitrogen, hydrogen, and other harmful gases in the steel continue to diffuse to the low partial pressure bubble until the bubble escapes from the steel. These processes realize the effects of steeling alloying, inclusion removal, deoxidation, desulfurization, and decarburization and improve the cleanliness of steel refining. [6][7][8] Therefore, optimizing the purging plug is key in regulating the flow of bubbles in the ladle to improve the refining effect. [9,10] Recently, various researchers have optimized the position of the purging plug, [11] number of purging plugs, [12,13] and angle of double bricks [14] to improve vortex distribution, shorten the alloy mixing time, reduce the steel temperature gradient, and improve the efficiency of the desulfurization and decarburization reactions. It is possible to change the type of purging plug to obtain an optimal bubble distribution. [15] Moreover, removing inclusions is more effective because of the larger surface area of small bubbles. [16] However, in some studies, [17,18] the bubble was ejected from a surface, or others simulated the gas ejected from the outlet of the purging plug. The distribution of the circular slits of the purging plug significantly influenced the bubble size. [19] To obtain an ideal bubble size, Rana et al. [20] focused on the effect of circular slits spacing on the bubble size. They found that the smaller the spacing of the slits to bubble diameter ratio is, the easier it is for the bubble to coalesce. Wraith [21] observed that during the bubble detachment phase, the bubble size directly depends on the shape and geometry of the nozzle opening. In addition, Jiang et al. [22] reported that the number of slits in the porous nozzle also affects the size of the bubbles, which also affects whether and when the bubbles coalesce during the rise, thereby affecting the average size of bubbles in the ladle. [23] Therefore, the distribution of the slits of the purging plug cannot be neglected for the size of the initial bubbles. Furthermore, the evolution of the initial bubble also affects the average size of bubbles in the ladle.In this study, based on the discrete phase model (DPM) of ANSYS, a file is used to define the position of the bubble sprayed into the slits, initial bubble diameter, and flow rate. The volume

Effect of Argon Flow Rate on Power Consumption of a 120‐t Ladle Furnace

“…This includes considerations for argon pressure, flow rate, and blowing time to achieve various refining phases aligned with specific metallurgical process objectives. [ 12,18,19 ] Maintaining a reasonable argon flow rate is essential to prevent arc leakage and promote the formation of foamy slag. This slag helps insulate the three electrodes located in the polar center circle, enabling them to heat the steel internally through the slag layer and molten pool surface.…”