Abstract:Pneumatic stirring plays an important role in melt mixing and reaction efficiency in the smelting process of large-scale copper smelting bottom-blown furnaces. In order to study the melt stirring phenomenon in a large bottom-blowing furnace with high temperature and confinement, Computational Fluid Dynamics (CFD) method was applied to establish an equivalent geometric model corresponding to the actual equipment, and the pneumatic stirring mechanism in a large bottom-blowing furnace was analyzed by numerical simulation. The results show that bubbles are the basic unit of pneumatic stirring in large bottom blown furnace. The periodic growth and separation, rising deformation, and melt surface fracture of bubbles transfer their kinetic energy to the melt and promote the homogenization of the composition in the molten pool. The continuously generated bubbles do work on the melt, providing sufficient mixing energy for the molten pool and the materials into the furnace. A core stirring zone and a clarification zone are formed in the molten pool, which provide good conditions for the reaction and separation of copper smelting process. The mechanism of pneumatic stirring obtained from the study has played a guiding role in the optimization design and engineering application of large-scale bottom blowing furnace in the future.