Bubble Motion and Gas-Liquid Mixing in Metallurgical Reactor with a Top Submerged Lance

Abstract

Abstract The multiphase fluid mixing and bubble motion in a scale-down Isa smelting furnace with a top submerged lance were investigated through cold water model experiments. The mixing time in the liquid bath was determined by a novel criterion, and the bubble formation frequency and gas-liquid contact area were also measured by high-speed photographing. The empirical equations of mixing time (Tm) relating to mixing energy (ε) were ${T_{{\rm{m}},s}} = 913{\varepsilon ^{ - 0.5}}$ for solid tracer and ${T_{{\rm{m}},l}} = 624{\varepsilon ^{ - 0.48}}$ for liquid tracer, respectively. The mixing time trended down with the increasing of bubble formation frequency, affected slightly by the bubbles with small size and decreased obviously when increasing the gas-liquid contact area. The optimal conditions of gas flow rate, bath height, lance submerged height and lance diameter to guarantee high-efficiency mixing and low-level surface fluctuation/splashing were obtained.