高锑粗铅电解体系下锑的二次富集机制与工艺装备协同优化

Mechanism of Secondary Antimony Enrichment and Collaborative Optimization of Process & Equipment in Electrolytic System of High-Antimony Crude Lead

摘要: 近些年铅冶炼进厂杂矿、再生铅固废配比持续走高，粗铅内部锑杂质常年超标，不少批次锑占比突破2.5%。本厂硅氟酸电解精炼产线长期运行后暴露出不少生产难题：电解液铅损耗快、槽内频繁短路、阳极泥结块难以清理，锑大量附着残极反复循环，回收效率偏低。依托厂区十万吨级电解产线开展全流程工业试验，分两步完成现场优化：第一步调整电解液管控、改造压滤装置、加装红外短路预警、加宽阴极板，通过多手段协同削弱高锑带来的副反应；第二步升级残极洗刷设备，采用双道往复刷辊结构，解决硬质锑泥剥离困难的现场痛点。长期现场运行数据显示，整套改造落地后，电解液铅离子稳定维持70 ± 1.5 g/L，阳极泥铅杂质从16.99%降至11.0%，电解电流效率稳定高于93%。即便将除铜粗铅锑含量拉满至2.5%极限负荷，阳极泥锑品位最高能达到54.18% ± 0.23%，实现锑在阳极泥内集中富集。这套改造方案不用提前火法脱锑，可直接用于高锑粗铅规模化生产，给国内同类型铅冶炼企业锑资源化回收提供可落地的现场改造思路。

Abstract: Complex antimony-bearing lead ores and secondary lead wastes are widely adopted in lead smelters in recent years, pushing the antimony mass fraction of crude lead to over 2.5% in partial batches. The conventional silicofluoric acid electrolysis line of our plant suffered from rapid lead ion consumption, frequent polar plate short-circuit, hardened anode slime and cyclic loss of antimony on residual anodes. Full-scale industrial trials were implemented on a 100,000-ton annual electrolysis line with two phases of optimization. In the first phase, multiple field adjustments including litharge supplementary feeding, filter press pneumatic upgrading, infrared short-circuit alarm and widened cathode plates were carried out to restrain adverse side reactions under high-antimony working conditions. In the second phase, the residual anode washing machine was reconstructed into dual-pass reciprocating brushing equipment to eliminate the difficulty of stripping hard antimony-rich slime. Long-term production monitoring data demonstrate that after comprehensive optimization, the Pb²⁺ concentration of electrolyte is stably controlled at 70 ± 1.5 g/L, lead impurity in anode slime drops from 16.99% to 11.0%, and electrolytic current efficiency remains above 93%. When treating copper-removed crude lead with antimony mass fraction of 2.5%, the maximum antimony grade of anode slime reaches 54.18% ± 0.23%, realizing centralized enrichment of antimony in anode slime. This integrated transformation scheme cancels pre-pyrometallurgical antimony removal, and can be applied to large-scale electrolysis of high-antimony crude lead, offering practical on-site renovation references for antimony resource recovery in lead smelting enterprises.