(中南大學(xué) 冶金科學(xué)與工程學(xué)院，長沙 410083)
摘 要: 通過對Fe2O3與碳酸鈉、氧化鈣以及硅酸鈣反應(yīng)的熱力學(xué)分析，明確Fe2O3在鋁土礦爐料燒結(jié)過程中的熱力學(xué)反應(yīng)規(guī)律。熱力學(xué)計算、分析結(jié)果表明：Fe2O3在正常燒結(jié)溫度范圍內(nèi)能與Na2CO3或CaO發(fā)生反應(yīng)，但更易與CaO反應(yīng)形成2CaO∙Fe2O3或CaO∙Fe2O3，Fe2O3和Na2O∙Fe2O3能使2CaO∙SiO2和3CaO∙2SiO2轉(zhuǎn)變?yōu)?/FONT>CaO∙SiO2，CaO∙SiO2進一步與Na2O∙Al2O3或Na2O∙Fe2O3反應(yīng)生成不溶的三元化合物而造成燒結(jié)法生產(chǎn)氧化鋁過程中Na2O和Al2O3的損失。4CaO∙Al2O3∙Fe2O3不能由鐵酸鈣和鋁酸鈉相互反應(yīng)產(chǎn)生，而可能是CaO、Al2O3和Fe2O3三者直接反應(yīng)的產(chǎn)物，且在燒結(jié)條件下Na2O∙Fe2O3可分解4CaO∙Al2O3∙Fe2O3。
關(guān)鍵字: 鋁土礦；熟料；燒結(jié)；Fe2O3；熱力學(xué)
ferric oxide during sinter-preparing process
（School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China）
Abstract:Based on the thermodynamic analyses of the reactions of ferric oxide(Fe2O3) with sodium carbonate, calcium oxide and calcium silicates, respectively, the thermodynamic of those reactions was determined. The results show that ferric oxide can react with sodium carbonate and calcium oxide respectively, but be more likely to react with calcium oxide to form calcium ferrite in the industrial sintering temperature range. Ferric oxide and sodium ferrite(Na2O∙Fe2O3) can transform 2CaO∙SiO2 and 3CaO∙2SiO2 into CaO∙SiO2, and CaO∙SiO2 can further react with Na2O∙Al2O3 or sodium ferrite to form insoluble ternary compounds, which results in the loss of sodium oxide and alumina during the alumina production by the sintering process. Calcium ferrite aluminate (4CaO∙Al2O3∙Fe2O3) can not form from the reaction of calcium ferrite(CaO∙Fe2O3, 2CaO∙Fe2O3) and sodium aluminate but rather is the direct product of the reaction of calcium oxide, alumina and ferric oxide. And calcium ferrite aluminate can be decomposed by sodium ferrite under the condition of sintering.
Key words: bauxite; sinter; sintering; Fe2O3; thermodynamics
