提出了一种废铅酸蓄电池胶泥低温熔盐还原固硫熔炼新工艺,该工艺以次氧化锌作固硫剂,焦粉为还原剂,在800~900℃的工业纯碱熔体中还原熔炼废铅酸蓄电池胶泥,实现了再生铅的低温、低碳、清洁冶炼。在理论分析的基础上,研究了工艺条件对熔炼过程的影响。结果表明,在纯碱质量为固态物的2.835倍、固硫剂为理论量的1.1倍、还原剂为胶泥的16%、熔炼温度为880℃的最优条件下,获得很好的冶炼指标:铅的直收率和总回收率分别为96.64%和98.06%,氧化锌固硫率为94.70%。新工艺具有低温、低碳、低耗、高效、清洁和过程简单等优点,对废铅酸蓄电池胶泥及铅烟尘等再生铅原料的清洁冶炼和原生铅(锑、铋)的清洁冶金均具有重要意义。
A new process for sulfur-fixing reduction smelting of spent lead-acid battery colloid sludge in fused salt at low temperature have been proposed.In the process,using crude zinc oxide as sulfur-fixing agent and coke powders as reducing agent,spent lead-acid battery colloid sludge can be reduced into crude lead in the molten salt of sodium carbonate at 800~900 ℃,realizing the low-temperature clean smelting of the secondary lead with little discharge of carbon dioxide.On the basis of thermodynamic analysis,the effects of technological factors on the smelting were investigated.The results indicate that excellent indexes such as direct and total recovery of lead being 96.64% and 98.06% respectively and sulfur-fixing rate of 94.70% for zinc oxide can be obtained under the optimum conditions as follows: the amount of sodium carbonate is 2.835 times of the solids weight,the dosage of zinc oxide is 1.1 times of the theoretical value,the dosage of coke powders is 16% of colloid sludge,and the smelting temperature is 880 ℃.The process has many advantages such as lower smelting temperature,little discharge of carbon dioxide,low cost,high efficiency,environment friendliness and simple operation.This process is of much significance to the clean smelting of the raw materials for secondary lead such as spent lead-acid battery colloid sludge and lead dusts as well as the clean metallurgy of primary lead sulfide concentrates.