Abstract:Applying the zinc leaching slag flotation silver concentrate from a certain zinc hydrometallurgy plant as raw material to study zinc removal by the process of reduction roasting in rotary furnace and low acid leaching. The results show that under the conditions of carbon powder dosage of 10%, roasting temperature of 600 ℃, roasting time of 120 minutes, particle size of raw material of —0.1 mm, and speed of rotary furnace of 5 r/min, the reduction roasting decomposition effect of zinc ferrite is optimal, and the soluble zinc content in the roasting product is 85.83%. The roasted products were selectively leached under the optimal conditions including endpoint pH value of 2, ratio of liquid to solid of 5 mL/g, leaching temperature of 70 ℃, and leaching time of 90 minutes, selective leaching of the roasting products is carried out, and the leaching rate of zinc and iron is 84.23% and 34.71% respectively. The undissolved iron and zinc oxides in leaching residue are mainly large particles agglomerated into clumps during reduction roasting process and some particles wrapped by melting lead sulfate.