Efficient removal of arsenic and antimony during blast furnace smelting of lead-containing materials.

Studies have been carried out on the use of a copper-zinc concentrate for the removal of As and Sb during the treatment of recycled Pb-containing materials in a blast furnace. Converter slag from the KAZZINC plant and Cu-Zn concentrate from the Nikolaevsky deposits in Kazakhstan were used. Results showed that, for an initial charge in the blast furnace of 26% converter slag, 30% Cu slips, 16% Cu-Pb matte, 4% caustic slag, 8% Cu-Zn concentrate, 8% silica flux, and 8% CaCO3 flux, the use of the Cu-Zn concentrate results in antimony and arsenic volatilisation 30% higher than with the current technology (based on the use of Cu-Zn ore). Arsenic and antimony extraction to the furnace dust is 84% instead of 63.3% , and 76% instead of 61%, respectively. Thermodynamic calculations for the smelting reaction showed that, at 1 573 K, there is an energetically preferred reaction of arsenic oxide and antimony oxide with the sulphur from the decomposition of CuFeS2 and FeS2. Maximum lead extraction to lead bullion and maximum volatilisation of As and Sb in the furnace dust were achieved with a Cu-Zn concentration flow rate of 20 wt% of converter slag. A thermodynamic calculation to provide a theoretical basis for the process is presented.
Studies have been carried out on the use of a copper-zinc concentrate for the removal of As and Sb during the treatment of recycled Pb-containing materials in a blast furnace. Converter slag from the KAZZINC plant and Cu-Zn concentrate from the Nikolaevsky deposits in Kazakhstan were used. Results showed that, for an initial charge in the blast furnace of 26% converter slag, 30% Cu slips, 16% Cu-Pb matte, 4% caustic slag, 8% Cu-Zn concentrate, 8% silica flux, and 8% CaCO3 flux, the use of the Cu-Zn concentrate results in antimony and arsenic volatilisation 30% higher than with the current technology (based on the use of Cu-Zn ore). Arsenic and antimony extraction to the furnace dust is 84% instead of 63.3% , and 76% instead of 61%, respectively. Thermodynamic calculations for the smelting reaction showed that, at 1 573 K, there is an energetically preferred reaction of arsenic oxide and antimony oxide with the sulphur from the decomposition of CuFeS2 and FeS2. Maximum lead extraction to lead bullion and maximum volatilisation of As and Sb in the furnace dust were achieved with a Cu-Zn concentration flow rate of 20 wt% of converter slag. A thermodynamic calculation to provide a theoretical basis for the process is presented.