(1. 中南大學(xué) 化學(xué)化工學(xué)院，有色金屬資源化學(xué)教育部重點實驗室，長沙 410083；
2. 株洲冶煉集團股份有限公司，株洲 412000)
摘 要: 對鋅浸出渣熔池熔煉碳還原煉鐵反應(yīng)過程進行了熱力學(xué)分析。結(jié)果表明：ZnFe2O4和KFe3(SO4)2(OH)6受熱分解的含鐵產(chǎn)物是Fe2O3，ZnFe2O4在300~1800 K溫度范圍內(nèi)不能自發(fā)分解，KFe3(SO4)2(OH)6在652.25K即可分解；高pCO/pCO2、低溫(但要高于爐渣熔融的溫度)有利于熔體中的Fe2O3還原生成液態(tài)鐵；含硫物相低溫分解后的產(chǎn)物有金屬硫酸鹽K2SO4和CaSO4，兩者熱分解脫硫的有利條件均是高溫及低硫分壓、低氧分壓(但氧分壓要高于硫酸鹽分解生成硫化物的限值)，CaSO4熱分解脫硫比K2SO4易于進行。鋅浸出渣中堿性氧化物CaO的存在，一方面可以降低Zn2SiO4碳熱還原的起始反應(yīng)溫度，另一方面可以提高爐渣堿度及爐渣中CaO的活度，降低硫在鐵液與爐渣中的分配平衡常數(shù)。
關(guān)鍵字: 鋅浸出渣；熔池熔煉；碳還原；煉鐵；熱力學(xué)分析；脫硫
（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
