Kinetics of coke gasification reaction process by improved segmentation attempt method
SHE Yuan1,2, ZHAN Wen-long3, ZOU Chong1, HAN Peng3, WU Keng2
1. School of Metallurgical Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, Shaanxi, China; 2. State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China; 3. School of Materials and Metallurgy, University of Science and Technology Liaoning, Anshan 114000, Liaoning, China
Abstract:As the main fuel of blast furnace ironmaking, coke plays a vital role in the normal operation of blast furnace and efficient smelting. With the development trend of large-scale intelligence of modern blast furnace and the continuous consumption of resources, the raw materials used to smelt high-quality metallurgical coke are gradually reduced. Low-quality metallurgical coke has attracted more and more attention of metallurgical workers. After determining the basic physical and chemical properties of coke in blast furnaces, the kinetics of different quality coke and CO2 gasification reaction processes under different heating rates were studied using the segmentation attempt method. The control mechanism of coke gasification reaction process was studied, which could be divided into two stages, the chemical reaction rate control in the early stage and the diffusion mass transfer rate control in the later stage. A two-stage speed control model was used to fit the gasification reaction process data, and then an unreacted shrinking core model for the chemical reaction rate control in the early stage and a shrinking core model for the diffusion mass transfer rate control in the later stage were established respectively. The conversion points, chemical reaction rate constant and mass transfer coefficient of the two control rates in reaction process were determined. Considering that the chemical reaction rate was nearly three orders of magnitude higher than the diffusion control rate, according to the irreversible thermodynamic phenomenological equation, the interference effect of chemical reaction process on the internal diffusion rate control process in the later stage of gasification reaction process was studied, and the valence coefficient in the phenomenological equation was determined. The latter diffusion speed control equation was modified, segmentation attempt method which was suitable for metallurgical reaction engineering to study reaction process kinetics was improved and its accuracy was further increased.
折媛, 湛文龙, 邹冲, 韩鹏, 吴铿. 改进分段尝试法研究焦炭气化反应动力学[J]. 钢铁, 2022, 57(4): 12-24.
SHE Yuan, ZHAN Wen-long, ZOU Chong, HAN Peng, WU Keng. Kinetics of coke gasification reaction process by improved segmentation attempt method[J]. Iron and Steel, 2022, 57(4): 12-24.
[1] 徐匡迪. 低碳经济与钢铁工业[J]. 钢铁 2010, 45 (3): 1. (XU Kuang-di. Low carbon economy and iron and steel industry[J]. Iron and Steel, 2010, 45 (3): 1.) [2] 王维兴. 高炉炼铁要实现节能减排[J]. 炼铁技术通讯, 2010, 28 (6): 1. (WANG Wei-xing. Energy saving and emission reduction in blast furnace ironmaking[J]. Iron Making Technology Journal, 2010, 28 (6): 1.) [3] 李克江, 张建良, 张亚鹏, 等. 基于节能减排思想分析炼铁工艺的发展[J]. 过程工程学报, 2014, 14 (1): 162. (LI Ke-jiang, ZHANG Jian-liang, ZHANG Ya-peng, et al. Analysis on the development of ironmaking process based on the idea of energy conservation and emission reduction[J]. The Chinese Journal of Process Engineering, 2014, 14 (1): 162.) [4] 吴铿, 折媛, 刘起航, 等. 高炉大型化后对焦炭性质及在炉内劣化的思考[J]. 钢铁, 2017, 52 (10): 1. (WU Keng, SHE Yuan, LIU Qi-hang, et al. Thoughts on coke properties and its deterioration in blast furnace after large-scale blast furnace[J]. Iron and Steel, 2017, 52 (10): 1.) [5] 朱利, 折媛, 湛文龙, 等. 焦炭高温性能对高炉焦炭负荷影响的生产实践[J]. 钢铁, 2018, 53 (4): 8. (ZHU Li, SHE Yuan, ZHAN Wen-long, et al. Practice for effect of coke high temperature properties on coke burden in blast furnace[J]. Iron and Steel, 2018, 53 (4): 8.) [6] 李克江, 李洪涛, 张建良, 等.高炉焦炭石墨化程度及其影响因素的研究进展[J]. 钢铁, 2020, 55 (7): 23. (LI Ke-jiang, LI Hong-tao, ZHANG Jian-liang, et al. Research progress on graphitization degree of blast furnace coke and its influencing factors[J]. Iron and Steel, 2020, 55 (7): 23.) [7] 吴铿, 张二华, 万鹏, 等. 关于COREX流程熔融气化炉风口前理论燃烧温度的思考[J]. 煤炭学报, 2010, 35 (10): 1730. (WU Keng, ZHANG Er-hua, WAN Peng, et al. Thoughts on theoretical combustion temperature in front of tuyere of COREX process melting gasifier[J]. Journal of China Coal Society, 2010, 35 (10): 1730.) [8] YANG J, SUN G, KANG C, et al. Oxygen blast furnace and combined cycle(OBF-CC)—An dfficient iron-making and power generation process[J]. Energy, 2003, 28 (8): 825. [9] Ohno Y, Matsuura M, Mitsufuji H, et al. Process characteristics of a commercial-scale oxygen blast furnace process with shaft gas injection[J]. ISIJ International, 1992, 32 (7):838. [10] 杨森, 吴铿, 万鹏, 等. 高炉风口焦热态性能的研究[J]. 冶金能源, 2010, 29 (1): 52. (YANG Sen, WU Keng, WAN Peng, et al. Study on thermal properties of blast furnace tuyere coke[J]. Energy for Metallurgical Industry, 2010, 29 (1): 52.) [11] 张黎, 吴铿, 杜瑞岭, 等. 分段尝试法研究半焦/CO2反应过程动力学[J]. 工程科学学报, 2016, 38 (11): 1539. (ZHANG Li, WU Keng, DU Rui-ling, et al. A sectioning method to study the gasification reaction kinetics of semicoke with CO2[J]. Chinese Journal of Engineering, 2016, 38 (11): 1539.) [12] 吴铿, 折媛, 朱利, 等. 对建立冶金反应工程学学科体系的思考[J]. 钢铁研究学报, 2014, 26 (12): 1. (WU Keng, SHE Yuan, ZU Li, et al. Thoughts on establishing the discipline system of metallurgical reaction engineering[J]. Journal of Iron and Steel Research, 2014, 26 (12): 1.) [13] DU R L, WU K, XU D A, et al. A modified Arrhenius equation to predict the reaction rate constant of Anyuan pulverized-coal pyrolysis at different heating rates[J]. Fuel Processing Technology, 2016, (148): 295. [14] 潘文, 吴铿, 赵霞, 等. 首钢烧结矿还原动力学研究[J]. 北京科技大学学报, 2013, 35 (1): 35. (PAN Wen, WU Keng, ZHAO Xia, et al. Study on reduction kinetics of Shougang sinter[J]. Journal of University of Science and Technology Beijing, 2013, 35 (1): 35.) [15] 折媛, 张文哲, 湛文龙, 等. 基于改进分段尝试法的高炉内热储备区焦炭熔损反应过程动力学研究[J]. 中南大学学报(自然科学版), 2021, 52 (12):4227. (SHE Yuan, ZHANG Wen-zhe, ZHAN Wen-long, et al. Investigation on the coke solution loss reaction kinetics in a blast furnace by modified sectioning method[J]. Journal of Central South University(Natural Science), 2021, 52 (12):4227.) [16] 张家芸. 冶金物理化学[M]. 北京: 冶金工业出版社, 2007. (ZHANG Jia-yun. Metallurgical Physical Chemistry[M]. Beijing: Metallurgical Industry Press, 2007.) [17] 吴铿, 刘起航, 湛文龙, 等. 分段法研究焦油析出动力学过程的探讨[J]. 高校化学工程学报, 2014, 28 (4): 738. (WU Keng, LIU Qi-hang, ZHAN Wen-long, et al. Study on kinetic process of tar precipitation by subsection method[J]. Journal of Chemical Engineering of Chinese Universities, 2014, 28 (4): 738.) [18] 巢昌耀, 吴铿, 杜瑞岭, 等. 煤粉与半焦的混合燃烧特性及动力学分析[J]. 工程科学学报, 2016, 38 (11): 1532. (CHAO Cang-yao, WU Keng, DU Rui-ling, et al. Combustion characteristics and kinetic analysis of pulverized coal and semicoke[J]. Chinese Journal of Engineering, 2016, 38 (11): 1532.) [19] 余润国, 陈彦, 林诚, 等. 高变质无烟煤催化气化动力学及补偿效应[J]. 燃烧科学与技术, 2012, 18 (1): 85. (YU Run-guo, CHEN Yan, LIN Cheng, et al. Catalytic gasification kinetics and compensation effect of high metamorphic[J]. Anthracite Combustion Science and Technology, 2012, 18 (1):85.) [20] 陈鸿伟, 吴亮, 索新良, 等. 浑源煤焦CO2气化反应的影响因素及动力学特性分析[J]. 动力工程学报, 2012, 32 (3): 255. (CHEN Hong-wei, WU Liang, SUO Xin-liang, et al. Analysis on influencing factors and kinetic characteristics of CO2 gasification reaction of Hunyuan coal char[J]. Journal of Chinese Society of Power Engineering, 2012, 32 (3): 255.) [21] 吴铿. 冶金传输原理[M]. 北京: 冶金工业出版社, 2016. (WU Keng. Metallurgical Transmission Principle[M]. Beijing: Metallurgical Industry Press, 2016.) [22] Degroot S R, Mazur P. 非平衡态热力学[M]. 上海: 上海科学出版社, 1981. (Degroot S R, Mazur P. Non-equilibrium Thermodynamics[M]. Shanghai: Shanghai Science Press,1981.) [23] Degroot S R, Mazur P. Non-equilibrium Thermodynamics[M]. Amsterdam: North-Holland Publishing Company,1962. [24] 彭少方, 张昭. 线性和非线性非平衡态热力学进展和应用[M]. 北京: 化学工业出版社, 2006. (PENG Shao-fang, ZHANG Zhao. Progress and Application of Linear and Nonlinear Nonequilibrium Thermodynamics[M]. Beijing: Chemical Industry Press, 2006.) [25] 翟玉春, 王锦霞. 均向单一化学反应的不可逆过程动力学[J]. 东北大学学报, 2004, 25 (10): 994. (ZHAI Yu-cun, WANG Jin-xia. Kinetics of irreversible process of homogeneous single chemical reaction[J]. Journal of Northeast University, 2004, 25 (10): 994.)