Kinetics for Iron Oxide in Reduction Process of Fe2O3-SiO2-Al2O3-CaO System
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摘要:
采用等温法和非等温法，考察了Fe2O3-SiO2-Al2O3-CaO体系深度还原过程的还原度和还原速率变化规律，并进行了系统的动力学分析。试验结果表明，还原温度对该体系深度还原反应的还原度和还原速率影响较大。等温法确定整个深度还原过程的机理函数符合Avrami-Erofeev方程，成核长大是反应的限制性环节，表观活化能和指前因子分别为288.21 kJ/mol和1.15×109 min-1。非等温法试验确定反应可分为前期、中期和后期三个阶段，中期主体反应阶段的机理函数符合Avrami-Erofeev方程，表观活化能和指前因子分别为272.60 kJ/mol和1.24×109 min-1。上述研究内容为进一步分析鲕状赤铁矿深度还原过程的动力学奠定基础。
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关键词:
- 深度还原 /
- 动力学 /
- Fe2O3-SiO2-Al2O3-CaO体系
Abstract:The kinetics of coal-based reduction process of Fe2O3-SiO2-Al2O3-CaO system was studied isothermally and non-isothermally combining with the change rules of reduction degree and reduction rate. Experimental results showed that the reduction degree and reduction rate of coal-based reduction process of Fe2O3-SiO2-Al2O3-CaO system were influenced by reduction temperature obviously. Mechanism function of entire isothermal coal-based reduction process was in accordance with Avrami-Erofeev kinetic model, and the reaction was controlled by the process of nucleation and development. The apparent activation energy and pre-exponential of isothermal coal-based reduction process were 288.21 kJ/mol and 1.15×109 min-1. Non-isothermal coal-based reduction process could be divided into initial, intermediate and final period. As the main reaction stage, the mechanism function of intermediate period also accorded with Avrami-Erofeev kinetic model. The apparent activation energy and pre-exponential of intermediate period were 272.60 kJ/mol and 1.24×109 min-1, respectively. The above research lays the foundation for further analysis of reduction kinetics of oolitic hematite ore.
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Key words:
- deep reduction /
- kinetics /
- Fe2O3-SiO2-Al2O3-CaO system
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表 1 试样初始成分 /%
Table 1. Initial composition of sample
成分 Fe2O3 SiO2 Al2O3 CaO 含量 62.12 23.35 6.21 8.32 
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表 2 焦炭的工业分析结果 /%
Table 2. Industrial analysis results of coke
成分 固定碳 挥发分 灰分 水分 S 含量 81.64 3.36 15.00 0.43 0.293
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[1] 赵立鹏, 李国峰, 张涛, 等.高磷鲕状赤铁矿深度还原过程中磷灰石还原热力学研究[J].矿产保护与利用, 2018(2):52-56. http://kcbh.cbpt.cnki.net/WKD/WebPublication/paperDigest.aspx?paperID=5dff7d24-4566-4ba3-ba6e-cea00bd7f423
[2] 李国峰, 高鹏, 韩跃新, 等.鄂西某鲕状赤铁矿石深度还原-弱磁选试验[J].金属矿山, 2013(8):53-56. doi: 10.3969/j.issn.1001-1250.2013.08.014
[3] 何洋, 王化军, 孙体昌, 等.铁矿石深度还原过程中助还原剂的作用及机理[J].哈尔滨工程大学学报, 2011, 32(12):1630-1636. doi: 10.3969/j.issn.1006-7043.2011.12.018
[4] 史广全, 孙永升, 李淑菲, 等.某鲕状赤铁矿深度还原过程研究[J].现代矿业, 2009(8):29-31. doi: 10.3969/j.issn.1674-6082.2009.08.010
[5] 贾岩, 倪文, 郑斐, 等.鲕状赤铁矿深度还原过程中铁粒生长特征研究[J].金属矿山, 2010(10):52-56. http://d.old.wanfangdata.com.cn/Periodical/jsks201010014
[6] HOU Baolin, ZHANG Haiying, LI Hongzhong, et al. Study on kinetics of iron oxide reduction by hydrogen[J]. Chinese journal of chemical engineering, 2012, 20(1):10-17. doi: 10.1016/S1004-9541(12)60357-7
[7] PANG Jianming, GUO Peimin, ZHAO Pei, et al. Influence of size of hematite powder on its reduction kinetics by H2 at low temperature[J]. Journal of iron and steel research, 2009, 16(5):7-11. doi: 10.1016/S1006-706X(10)60002-7
[8] Krzysztof Piotrowski, Kanchan Mondal, Hana Lorethova, et al. Effect of gas composition on the kinetics of iron oxide reduction in a hydrogen production process[J]. International journal of hydrogen energy, 2005, 30(15):1543-1554. doi: 10.1016/j.ijhydene.2004.10.013
[9] K. Mondal, H. Lorethova, E. Hippo, et al. Reduction of iron oxide in carbon monoxide atmosphere-reaction controlled kinetics[J]. Fuel processing technology, 2004, 86(1):33-47. doi: 10.1016/j.fuproc.2003.12.009
[10] 魏徳洲.固体物料分选学[M].北京:冶金工业出版社, 2000:103-105.
[11] 姚梅琴, 余剑, 郭凤, 等.氧化铁石墨固相还原非等温反应动力学[J].化工学报, 2013, 64(6):2072-2079. doi: 10.3969/j.issn.0438-1157.2013.06.024
[12] Li Y L, Sun T C, Zou A H, et al. Effect of coal levels during direct reduction roasting of high phosphorus oolitic hematite ore in a tunnel kiln[J]. International journal of mining science and technology, 2012, 22:323-328. doi: 10.1016/j.ijmst.2012.04.007
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