Study on the mixing characteristics of multiphase in nonlinear blowing-stirring systems and experimental application

Abstract

The mixing efficiency of multiphase flow in mechanical mixing and mechanical mixing coupled with uniform-blowing (UB) systems is poor in the chemical industry. To enhance the mixing efficiency of multiphase flow in the reactor, a mechanical mixing system coupled with variable-speed blowing (VSB) system was proposed. The VSB mixing system was designed and applied to the experiment of leaching indium from the waste indium tin oxide (ITO) target. The discrete element method−volume of fluid (DEM-VOF) model was used to study the flow state, movement information, and distribution uniformity of particles in the VSB system. The average relative standard deviation (RSD) for the without-blowing (WB), UB, and VSB mixing systems was 0.89, 0.72, and 0.68, respectively. The average RSD of the VSB system was 30.61 % and 5.6 % lower than that in the WB system and the UB system, respectively. Therefore, the distribution uniformity of ITO powder in the VSB system is better. When the leaching time increased by 120 min, the leaching rates of indium in WB, UB, and VSB mixing systems were 75.26 %, 91.03 %, and 95.51 %, respectively. The leaching rate of indium in the VSB system, increased by 22.25 % and 4.48 % in contrast with the WB system and the UB system. Recycling the scarce metal indium plays a crucial role in promoting environmental sustainability and meeting high industrial demand.