硫酸铅定向还原及氧化亚铁诱导强化固硫绿色提铅过程三相平衡调控机制

密闭富氧负压炉还原固硫定向熔炼是国家推荐的涉重金属重点行业清洁生产先进适用技术，能高效处置回收复杂含铅固废。但技术瓶颈在于“粗铅-铁锍-炉渣”三相产物内铅行为分散，铁锍含未反应的PbS较高(10wt.%-15wt.%)，阻碍了其工程应用。针对上述问题，本项目提出含铅固废还原固硫诱导强化绿色提铅技术思路，通过定向还原硫酸铅制备硫化铅，诱导强化硫化铅-氧化亚铁交互反应动力学，优化“铁锍-炉渣”组成，定向调控“粗铅-铁锍-炉渣”三相平衡，实现铅定向富集。项目重点研究突破还原体系铅盐高效转化技术、还原诱导强化固硫绿色提铅技术和“粗铅-铁锍-炉渣”三相平衡铅定向富集技术，查明硫化铅转化反应动力学强化机制，揭示氧化亚铁诱导强化固硫提铅界面行为及相转化机理，摸清“铁锍-炉渣”组成优化及“粗铅-铁锍-炉渣”三相平衡调控机制，最终构建还原固硫诱导强化绿色提铅技术原型，助力该技术工程化推广应用。

Reductive sulfur-fixing directional smelting in the closed oxygen-rich negative pressure furnace is an advanced and applicable technique recommended by China for clean production in key industries related to heavy metals. It enables to recycle lead-containing solid wastes in high efficiency with broad prospects for industrialization. However, the main problems lie in the dispersion of lead behavior in the obtained "crude lead-matte-slag" polyphase products, and the high unreacted and remained PbS in ferrous matte (10 wt.%-15 wt.%), which hinders its industrialization and application. In view of the above issues, this project proposed a technical idea of inductively strengthened reductive sulfur-fixation for green lead-extraction from lead-containing solid wastes. Firstly, lead sulfide was prepared by directional reduction from lead sulphate, then the interaction kinetics of reaction between lead sulfide and ferrous oxide was induced and enhanced, and the composition of matte and slag was optimized, finally, metallic Pb was directionally enriched in crude lead product by controlling the three-phase equilibrium of "crude lead-matte-slag". The project focuses on and breaks through the technologies of high-efficient conversion of lead salt in reduction system, the green lead extraction inductively strengthened by reduction and sulfur-fixation reactions, and lead directional enrichment in the "crude lead-matte-slag" three-phase equilibrium system. Thus, the kinetic strengthening mechanism of lead sulfide conversion reactions was identified, the interface behavior and phase transformation mechanism of lead extraction reactions involved enhanced sulfur-fixation and induced by ferrous oxide were revealed, and the "matte-slag" composition optimization strategy as well as the three-phase equilibrium law and controlling mechanism of "crude lead-matte-slag" were figured out. Finally, a prototype for green lead extraction enhanced by reductive sulfur-fixation reactions was expected to be constructed, contributing to promoting the engineering application of this technology.