(1. 中南大学 化学化工学院，有色金属资源化学教育部重点实验室，长沙 410083；
2. 株洲冶炼集团股份有限公司，株洲 412000)
摘 要: 对锌浸出渣熔池熔炼碳还原炼铁反应过程进行了热力学分析。结果表明：ZnFe2O4和KFe3(SO4)2(OH)6受热分解的含铁产物是Fe2O3，ZnFe2O4在300~1800 K温度范围内不能自发分解，KFe3(SO4)2(OH)6在652.25K即可分解；高pCO/pCO2、低温(但要高于炉渣熔融的温度)有利于熔体中的Fe2O3还原生成液态铁；含硫物相低温分解后的产物有金属硫酸盐K2SO4和CaSO4，两者热分解脱硫的有利条件均是高温及低硫分压、低氧分压(但氧分压要高于硫酸盐分解生成硫化物的限值)，CaSO4热分解脱硫比K2SO4易于进行。锌浸出渣中碱性氧化物CaO的存在，一方面可以降低Zn2SiO4碳热还原的起始反应温度，另一方面可以提高炉渣碱度及炉渣中CaO的活度，降低硫在铁液与炉渣中的分配平衡常数。
关键字: 锌浸出渣；熔池熔炼；碳还原；炼铁；热力学分析；脱硫
（1. Key Laboratory of Resources Chemistry of Nonferrous Metals, Ministry of Education,
College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China;
2. Zhuzhou Smelter Group Co., Ltd., Zhuzhou 412000, China）
Abstract:Iron-making of zinc leaching residue was obtained by carbon reduction in bath smelting, and the thermodynamic process was analyzed. The results show that Fe2O3 is the pyrolysis product of ZnFe2O4 and KFe3(SO4)2(OH)6. ZnFe2O4 can not decompose in the temperature range of 300-1800 K, but KFe3(SO4)2(OH)6 decomposes at 652.25K. Higher pCO/pCO2 and lower temperature that should be higher than the slag melting temperature, are favor able to the reduction of Fe2O3. The metal sulfates of K2SO4 and CaSO4 are decomposing products of sulfur-contained phases at low temperature, and the favorable desulfurization conditions of K2SO4 and CaSO4 are high temperature, low sulfur-partial pressure and low oxygen-partial pressure that must be higher than the limit of sulfates converting into sulfides. The desulfurization of CaSO4 is easier than that of K2SO4. CaO in zinc leaching residue reduces the initial reaction temperature of Zn2SiO4 reduction, improves slag basicity and activity of CaO in slag and decreases the sulfur distribution ratio between liquid iron and molten slag.
Key words: zinc leaching residue; bath smelting; carbon reduction; iron-making; thermodynamic analysis; desulfurization
