Improvement of Sulfatizing Roasting of Refractory Copper-Zinc Sulphide Raw Material

Sulfatization roasting of refractory copper-zinc sulphide raw material is studied. Test material chemical and phase compositions are examined. Thermodynamic calculations of possible sulfatization reactions are performed. Phase transformations, mechanisms of decomposition, and oxidation of sulphide minerals are studied using thermogravimetric and differential-thermal analyses. Equilibrium distribution of the system components during copper-zinc sulphide raw material roasting is modelled using an HSC Chemistry 6.0 computer program. Optimum conditions are established for roasting in which copper and zinc sulphide minerals are converted into sulphate form and iron is converted into oxide. Consolidated tests of sulfatizing roasting of copper-zinc sulphide middlings confirm results of experimental studies.