China Nonferrous Metallurgy

In Kaldor furnace process for copper anode slime pyro-treatment, the slag performance will be affected by BaSO₄ from demoulding agent, and the anode slime composition changes upon batches. So the slag composition and operating parameters in smelting process should be adjusted accordingly to reach better results. Up to now, there is fewer research results on the properties of BaSO₄ containing slag. Based on relevant parameters from copper anode slime pyro-treatment practice, the slagphase diagrams of Na₂O-SiO₂-PbO-BaO system were calculated with FactSage and BaSO₄ ontent in 5%~50%in this paper. The slag melting point inrelevant composition was measured . The feasible Na₂O/SiO₂ in correspondant with BaSO₄ content was obtained. The slag melting points can be controlled under 1000℃ without increase the slag amount. The slag fluidity and the recovery of metal can be improved as a result.To promote the smelting process,it is proposed to improve smelting efficiency and reduce heat loss, to strengthen the batching controland the examination of Ba and Si in anode slimeto reduce BaSO₄ content in the slime, keep the stability of the process operation in the reduction smelting stage to ensure better match of furnace temperature and slag performance.