Abstract:As a modern copper smelting process, oxygen enriched bottom blown smelting technique has been widely used in China. 3D numerical simulations were performed focusing on problems of low smelting efficiency and high copper loss in slag in largest bottom-blown copper smelting furnace. With goal of improving smelting bath stirring and reducing copper loss in slag, oxygen lance quantity and smelting bath depth were optimized. The results show that changing number of oxygen lances near the slag outlet has a significant positive effect on increasing length of clarification zone and reducing copper loss in slag. After closing two oxygen lances, slag-matte clarification zone extends by 27.425% and 0.925 m compared with the original condition, while slag-matte clarification zone extends by 50.165% and 1.695 m after closing four oxygen lances. According to gas holdup in stirring zone of smelting bath and stirring effect, the suitable depth range of smelting bath is 1.5 m to 1.7 m.