关键词: 底吹+侧吹炼铅, 高浸铅银渣, 炉渣性能, 渣型调控, 工艺优化

Abstract: The comprehensive recovery and complementation of lead and zinc resources is the main developing trend for lead and zinc enterprises. This work aim is to solve the problems, such as lack of heat in oxidizing smelting, difficulty in process control of slag, poor stability of reducing slag, etc, emerged in the bottom blowing-side blowing lead smelting system mixed with lead?silver leaching residues in Hanzhong Zinc Industry Co., LTD. On the basis of comprehensive evaluation of the original process, thermodynamic analysis on dominant region and phase diagram of melting process were calculated, the slag properties were determined, and subsequently, optimizing process based on regulation of slag system were put forward. The results showed that the temperature of oxidizing smelting was raised to 1050℃ and the reduction smelting was lowered to 1250℃, though adjusting heating mode of the bottom blowing furnace from sulfur to bituminous coal and pyrite as auxiliary. The direct lead-smelting process mixed with lead-containing residues can be operated smoothly though controlling reduction smelting slag, in which FeO/SiO2 mass ratio was 1.2?1.6, CaO/SiO2 mass ratio was 0.4?0.6, and ZnO≤20wt%. After process optimization, the ratio of oxygen to material decreased from 120 Nm3/t to 110 Nm3/t, and the proportion of lead?silver leaching slag mixed in charge materials increased to 24wt%. In the meanwhile, the dust content of smelting flue gas in oxidation and reduction smelting reduced by 13.47% and 15.82%, respectively, and the cost of crude lead reduced by 10.63% as a result.

Key words: the bottom blowing-side blowing lead smelting, lead-silver leaching residues, slag properties, slag type regulation, process optimization