Immersion Bath Smelting Lead And Zinc Slags

In this paper,we explored the immersion bath smelting of hydrometallurgy leaching slag and Kivcet slag to recycle lead and zinc based on the thermodynamic calculation and slag-type analysis,and the optimumest slag-type and process condition were obtained.The results indicated that immersion bath smelting process has high efficiency to recycle lead,zinc and other valuable metals as well as the main technical indicators are favorable.Thermodynamic calculation results show that the appropriate temperature of the bath smelting of the lead-zinc bearing slag should be controlled between 1150 to 1300? to avoid iron generation.The evaporation rate of lead was faster than zinc.So,the evaporation of lead was more thorough when the the smelting conditions meet the vaporation of zinc.The melting-point of zinc hydrometallurgy slag ranges from 1100? to 1300 ?.The zinc slag has a good liquidity at the conditions of : temperature1250?,CaO/SiO₂=0.75,1?Fe₂O₃/SiO₂?9.8,and the viscosity of leaching slag is between 0.6 to 0.7 Pa·S,meanwhile,the zinc evaporation rate was higher than 96%.This conditions also satisfied the requirements to slag bath smelting process.The average content of lead and zinc in the tailings from the immersion bath smelting process of zinc leaching residue were 0.033% and 0.34%,and the average evaporation rate of lead and zinc were 96.39% and 97.06% at the optimum conditions which were W_coke/W_slag=1/2.8,smelting temperature 1250 ?,smelting time1 h,particles size 10¹20 mesh,water content lower than10%.The FeO/SiO₂ of the lead-zinc mixture materials?zinc hydrometallurgy leaching slag and Kivcet lead smelting slag?increased as the addtion of the zinc leaching slag was increased,while the CaO/SiO₂ has hardly difference.The volatilization rates of zinc and lead reach 95% and 94% in the immersion bath smelting process using mixture materials.But the proportion of the Kivcet lead slag should be lower than 50%.This research can provide a new idea and technical support for the disposal of the complex lead-zinc slag generated in lead and zinc smelting enterprise,which has a widely application prospects.