NOUFERROUS METALLURGICAL EQUIPMENT

Lead-silver slag produced by zinc hydrometallurgy will pollute the environment for a long time, so it is necessary to comprehensively recover valuable metals in lead-silver slag. Lead-silver slag produced in the process of comprehensive recovery hot acid leaching-jarosite method is treated by side blowing furnace melting + fuming furnace fuming process. The main process of the process includes two stages: melting of zinc leaching slag and reduction and volatilization of lead and zinc. In the melting process, the phase structure of lead-silver slag changes, the heavy metal ions wrapped can be released, the grade of valuable metals can be improved, and the sulfur content of molten residue can be reduced, which is beneficial to metal volatilization. Therefore, the lead-silver slag needs to be pretreated by desulfurization.In the paper, the research direction of desulfurization experiment of lead-silver slag is determined by the dominant zone diagram of Me-S-O system, and the effects of three factors, namely, volume ratio of nitrogen to oxygen, melting desulfurization time and melting desulfurization temperature, on desulfurization rate of lead-silver slag are investigated.The best technological conditions of melting desulfurization are as follows: nitrogen atmosphere, melting desulfurization time 40min, melting desulfurization temperature 1250℃, and the desulfurization rate is 98.17% under these conditions.The study has practical significance for comprehensive recovery of lead-silver slag desulfurization pretreatment process.