|
|
Softening-melting properties of blast furnace charge with pre-dehydrated lump iron ore |
PANG Zhuo-gang1, DING Wang2, YU Yuan-hao1, WANG Guang1, CHEN Yan-biao1, ZUO Hai-bin1 |
1. State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China; 2. Ironmaking Plant, Hunan Valin Xiangtan Iron and Steel Co., Ltd., Xiangtan 411101, Hunan, China |
|
|
Abstract The addition of natural lump iron ore to blast furnace is of great significance to reduce carbon emissions in ironmaking process. Pre-dehydrate treatment was applied to C4 ore to improve the deterioration of gas permeability and softening-melting performance of furnace charge caused by the decrepitation of Australian C4 ore. The decrepitation and melting-dropping performance of natural and pre-dehydrated C4 ore were investigated, and the effect of pre-dehydrated C4 ore ratio (12%-24%) on the softening-melting performance of ferrous burden was also studied. The results showed that with the temperature increased from 600 ℃ to 900 ℃, the decrepitation index of natural C4 ore rapidly increased from 8.05% to 22.5%, while that of pre-dehydrated C4 ore only increased from 3.38% to 7.11%. The initial softening temperature (t10) and dripping temperature (td) of sintering ores were higher, but the melting zone was narrowest. And the sintering ores have better comprehensive dropping performance, followed by pellet ore and C4 ores. Compared with natural C4 ore, the initial softening temperature of pre-dehydrated C4 ore was increased by 82 ℃, and the melting initial temperature (ts) increased by 47 ℃. But the softening zone (t40-t10) and melting zone (td-ts) reduced by 26 ℃ and 50 ℃, respectively. Although the cohesive zone moved to the high temperature zone, the maximum differential pressure (ΔPm) of natural C4 ore and pre-dehydrated C4 ore and permeability index (S) were both high. Thus, the excessive addition of C4 ore was not conducive to smooth blast furnace operation. Compared with the burden structure of 76% sintering ore and 24% pellet ore, the softening zone of burden structure with C4 ore was narrower, while the melting zone was wider, and ΔPm and S values increased significantly. When the proportion of pre-dehydrated C4 ore in burden structure increased from 12% to 18%, the softening zone and melting zone narrowed and the cohesive zone shifted to the high temperature zone, which is due to the decrease of the slag mass percent and the easier occurrence of carburization. However, when the proportion of pre-dehydrated C4 ores exceeded 18%, the strength of the ferrous burden dramatically reduced, which led to the decrease in the initial softening temperature and initial melting temperature, and the maximum differential pressure of furnace increased. Based on the current raw material conditions, the suitable addition ratio of pre-dehydrated C4 ore is 18%. Using this burden structure to smelt 1 t hot metal in the blast furnace could reduce 53.82 kg CO2 emissions.
|
Received: 25 October 2022
|
|
|
|
[1] 王新东, 金永龙. “双碳”背景下高炉使用高比例球团的展望[J]. 过程工程学报, 2022, 22(10): 1379.(WANG Xin-dong, JIN Yong-long. Prospect on high ratio pellet utilized in Blast Furnace under the background of dual carbon[J]. The Chinese Journal of Process Engineering, 2022, 22(10):1379. [2] 薛英岚, 张静, 刘宇, 等. “双碳”目标下钢铁行业控煤降碳路线图[J]. 环境科学, 2022, 43(10): 4392. (XUE Ying-lan, ZHANG Jing, LIU Yu, et al. Roadmap of coal control and carbon reduction in the steel industry under the carbon peak and neutralization target[J]. Environmental Science, 2022, 43(10): 4392.) [3] WU Sheng-li, HAN Hong-liang, XU Hai-fa, et al. Increasing lump ores proportion in blast furnace based on the high-temperature interactivity of iron bearing materials[J]. ISIJ International, 2010, 50(5): 686. [4] 李胜杰, 张希刚, 赵恒山. 安钢2号高炉经济块矿生产实践与成本分析[J]. 中国冶金, 2014, 24(10): 39. (LI Sheng-jie, ZHANG Xi-gang, ZHAO Heng-shan. Practice and cost analysis of proportioning economic lump ore of Angang No.2 BF[J]. China Metallurgy, 2014, 24(10): 39.) [5] 左海滨, 于文涛, 张建良. 温度对天然块矿爆裂的影响[J]. 钢铁, 2015, 50(5): 7. (ZUO Hai-bin, YU Wen-tao, ZHANG Jian-liang. Effects of temperature on the decrepitation performance of natural lump ores[J]. Iron and Steel, 2015, 50(5): 7.) [6] 张军红, 刘颖超, 佘雪峰, 等. 不同块矿炉料结构下炉料冶金性能研究[J]. 烧结球团, 2021, 46(5): 79.(ZHANG Jun-hong, LIU Ying-chao, SHE Xue-feng, et al. Study on metallurgical performance of furnace material under different lump ore furnace structures[J]. Sintering and Pelletizing, 2021, 46(5): 79.) [7] Mizutani Moritoshi, Nishimura Tsunehisa, Orimoto Takashi, et al. In-situ evaluation method for crack generation and propagation behaviors of iron ore burden during low temperature reduction by applying acoustic emission method[J]. ISIJ International, 2018, 58(8): 1413. [8] 邸航, 杜屏, 王永红, 等. 2 680 m3高炉使用非主流块矿的稳产降本实践[J]. 中国冶金, 2022, 32(3): 68. (DI Hang, DU Ping, WANG Yong-hong, et al. Practice of yields stability and cost reduction in 2 680 m3 blast furnace with non-mainstream ores[J]. China Metallurgy, 2022, 32(3): 68.) [9] NIU Le-le, ZHANG Jian-liang, WANG Yao-zu, et al. Lump iron ore pre-heating treatment to improve softening-melting performance and reduce energy consumption in ironmaking process[J]. JOM, 2022, 74(7): 2733. [10] YANG Wen-jing,ZHOU Zong-yan,Pinson David,et al. A new approach for studying softening and melting behavior of particles in a blast furnace cohesive zone[J]. Metallurgical and Materials Transactions B, 2015, 46(2): 977. [11] 刘杰, 张洪宇, 周明顺, 等. 基于软熔滴落性能的高炉合理炉料结构[J]. 钢铁, 2016, 51(9): 11.(LIU Jie, ZHANG Hong-yu, ZHOU Ming-shun, et al. Rational burden structure of blast furnace based on softening and melting property[J]. Iron and Steel, 2016, 51(9): 11.) [12] 李胜, 何志军, 李云飞, 等.不同球团矿和块矿配加条件下炉料冶金性能[J]. 钢铁, 2020, 55(1): 6.(LI Sheng, HE Zhi-jun, LI Yun-fei, et al. Metallurgical properties of furnace charge under different conditions of pellet ore and block ore addition[J]. Iron and Steel, 2020, 55(1): 6.) [13] WU Sheng-li, TUO Bi-yang, ZHANG Li-hua, et al. New evaluation methods discussion of softening-melting and dropping characteristic of bf iron bearing burden[J]. Steel Research International, 2014, 85(2): 233. [14] 冷长明, 姜鑫, 薛庆斌, 等. 高比例酸性炉料对高炉操作的影响及应对措施[J]. 钢铁, 2022, 57(7): 16.(LENG Chang-ming, JIANG Xin, XUE Qing-bin, et al. Effects of high proportion of acid burden on blast furnace operation and its countermeasure[J]. Iron and Steel, 2022, 57(7): 16.) [15] 祁成林, 冯根生, 许满兴, 等. 高炉冶炼条件下天然块矿热裂指数评价新方法[J]. 烧结球团, 2022, 47(2): 67.(QI Cheng-lin, FENG Gen-sheng, XU Man-xing, et al. A new method for evaluating decrepitation index (DI) of natural lump ore under BF ironmaking[J]. Sintering and Pelletizing, 2022, 47(2): 67.) [16] Fariaa G L, Jannottib N, Da SilvaAraújo F G. Decrepitation behavior of manganese lump ores[J]. International Journal of Mineral Processing, 2012, 102(1):150. [17] 刘鹏飞, 郑丽丽, 郭卓团. 蒙古铁矿块矿直接入炉基础冶金性能[J]. 钢铁研究学报, 2019, 31(10): 882. (LIU Peng-fei, ZHENG Li-li, GUO Zhuo-tuan. Research on metallurgical properties of Mongolian lump ore[J]. Journal of Iron and Steel Research, 2019, 31(10): 882.) [18] 陈小敏, 湛文龙, 杜晓东, 等. 烧结矿在高炉内熔滴性能新方法表征与预测的研究[J]. 冶金能源, 2022, 41(2): 29.(CHEN Xiao-min, ZHAN Wen-long, DU Xiao-dong, et al. Investigation on a new method for predicting and characterizing the melting property of sinter in blast furnace[J]. Energy for Metallurgical Industry,2022, 41(2): 29.) [19] Ismael Vemdrame Flores, Ota' Vio Matos, Aline Lima Da Silva, et al. Microstructure and porosity evolution during the reduction, softening and melting of iron-bearing materials[J]. Metallurgical and Materials Transactions B, 2021, 52(3), 1716. [20] CHEN Yan-biao, LIU Wen-guo, WU Hua-jie, et al. Production of pre-reduced sinter based on sensible heat updraft of sinter[J]. Powder Technology, 2022, 411(1): 117911. [21] QIE Ya-na, LYU Qing, LIU Xiao-jie, et al. Effect of hydrogen addition on softening and melting reduction behaviors of ferrous burden in gas-injection blast furnace[J]. Metallurgical and Materials Transactions B, 2018, 49(5), 2622. |
[1] |
ZHU Rong, REN Xin, XUE Bo-tao. Research progress of ultimate carbon emission in BOF steelmaking process[J]. Iron and Steel, 2023, 58(3): 1-10. |
[2] |
LENG Chang-ming, JIANG Xin, XUE Qing-bin, LONG Fang, HUO Hong-yan, SHEN Feng-man. Effects of high proportion of acid burden on blast furnace operation and its countermeasures[J]. Iron and Steel, 2022, 57(7): 16-25. |
[3] |
ZHU Ren-liang. Discussion on future development direction of ironmaking technology and exploratory practice of Baosteel[J]. Iron and Steel, 2020, 55(8): 2-10. |
[4] |
ZHANG Shu-hui, WANG Bao-yong, LAN Chen-chen, LIU Xiao-jie, LÜ Qing. Prospects and present status of pellets chemical composition control[J]. Iron and Steel, 2020, 55(8): 19-26. |
[5] |
ZHU De-qing,XUE Yu-xiao,PAN Jian,TIAN Hong-yu,PAN Liao-ting,HUANG Qing-zhou. Sintering performance and mechanism of limonite laterite strengthened by using waste lump ore as hearth layer[J]. JOURNAL OF IRON AND STEEL RESEARCH , 2020, 32(7): 591-600. |
[6] |
LI Sheng, HE Zhi-jun, LI Yun-fei, QIU Shuang, ZHAN Wen-long, BAI Bing-yang. Metallurgical properties of furnace charge under different conditions of pellet ore and block ore addition[J]. Iron and Steel, 2020, 55(1): 6-11. |
|
|
|
|