Influence mechanism of basicity on strength of magnesium fluxed pellets
LIU Wei-xing1, LI Jie1, YANG Ai-min2, ZHANG Yu-zhu1, XIN Zi-cheng1
1. Modern Metallurgical Technique Key Laboratory of Ministry of Education, North China University of Science and Technology, Tangshan 063009, Hebei, China; 2. College of Science, North China University of Science and Technology, Tangshan 063009, Hebei, China
Abstract:To investigate the influence mechanism of basicity on the strength of magnesium fluxed pellets, based on the raw materials of a steel plant in Tangshan city, using pelleting and roasting experiment, with the help of XRD, polarized light microscope, field emission scanning electron microscope analysis and Matlab software calculation analysis, the mechanism of the influence of alkalinity on the compressive strength of pellets is analyzed in depth from the aspects of pellet mineral composition, liquid phase formation, and microstructure, micromorphology and element distribution. The results show that with the increase of basicity, the compressive strength of the pellets increases. Hematite is the main crystal in pellets. The liquid phase is mainly composed of calcium ferrite, calcium silicate, and a little quartz. After the basicity is higher than 0.8, a small amount of magnesium ferrite appears in pellets. As the basicity increasing, the hematite content and liquid phase content increase, density increases, the pore become more uniform, and compressive strength increases of pellets. The Ca, Si, and Mg have the same distribution, Fe and O have the same distribution, and the two groups of elements′ distribution is complementary in pellets. As the basicity increases, the content of Ca, Si, and Mg elements increases, the content of the liquid phase increases, compressive strength increases of pellets. The analysis results of the two are consistent and have been mutually confirmed.
刘卫星, 李杰, 杨爱民, 张玉柱, 信自成. 碱度对镁质熔剂性球团矿强度的影响机理[J]. 钢铁, 2021, 56(1): 28-36.
LIU Wei-xing, LI Jie, YANG Ai-min, ZHANG Yu-zhu, XIN Zi-cheng. Influence mechanism of basicity on strength of magnesium fluxed pellets[J]. Iron and Steel, 2021, 56(1): 28-36.
[1] 张林林,付刚华,郭宇峰,等. 碱度对熔剂性球团生球性能的影响[J].钢铁,2019,54(5):14.(ZHANG Lin-lin, FU Gang-hua, GUO Yu-feng, et al. Effect of basicity on quality of green fluxed pellets[J]. Iron and Steel, 2019, 54(5):14.) [2] 张福明.首钢绿色低碳炼铁技术的发展与展望[J].钢铁,2020,55(8):11.(ZHANG Fu-ming. Developmeng and prospect of green and low carbon ironmaking technologies in Shougang[J]. Iron and Steel, 2020,55(8):11.) [3] 王新东, 郝良元, 胡启晨, 等. 河钢集团高炉炼铁技术进步[J]. 中国冶金, 2020, 30(1): 73.(WANG Xin-dong, HAO Liang-yuan, HU Qi-chen, et al. Progress in blast furnace ironmaking technology of HBIS Group[J]. China Metallurgy, 2020, 30(1): 73.) [4] 张福明.中国高炉炼铁技术装备发展成就与展望[J].钢铁,2019,54(11):1. (ZHANG Fu-ming. Prospcet and development achievements of blast furnace iromaking technologies and equipments in China[J]. Iron and Steel, 2019,54(11):1.) [5] 侯恩俭,翁兴洋,范晓慧. 纤维化复合膨润土强化氧化球团制备研究[J].烧结球团,2019,44(4):40.(HOU En-jian, WENG Xing-yang, FAN Xiao-hui. Study on strengthening preparation of oxide pellets with fibration composite bentonite[J]. Sintering and Pelletizing, 2019,44(4):40.) [6] 范晓慧,田志远,甘敏,等. 细粒磁铁精矿球团孔隙结构的优化研究[J]. 矿冶工程,2018,38(1):71.(FAN Xiao-hui, TIAN Zhi-yuan, GAN Min, et al. Optimization of pore structure of fine-grained magnetite concentrate pellets[J]. Mining and Metallugical Engineering, 2018, 38(1):71.) [7] 范晓慧,谢路奔,甘敏,等. 高镁球团焙烧特性及其固结强化机理[J].中南大学学报(自然科学版),2013,44(2):449. (FAN Xiao-hui, XIE Lu-ben, GAN Min, et al. Roasting characteristics of magnesium pellets and mechanism of strengthening concretion[J]. Journal of Central South University(Natural Science), 2013, 44(2):449.) [8] 范晓慧,甘敏,陈许玲,等. 低碱度镁质氧化球团的试验研究[J].钢铁,2009,44(3):6.(FAN Xiao-hui, GAN Min, CHEN Xu-ling, et al. Experiments of low-basicity magnesian oxidized pellets[J]. Iron and Steel, 2009, 44(3):6.) [9] FAN Xiao-hui, GAN Min, JIANG Tao, et al. Influence of flux additives on iron ore oxidized pellets[J]. Journal of South University of Technology, 2010, 17(4): 732. [10] 青格勒,王朝东,侯恩俭,等. 低硅含镁球团矿抗压强度及冶金性能[J]. 钢铁研究学报,2014,26(4):7.(QING Ge-le, WANG Chao-dong, HOU En-jian,et al. Compressive strength and metallurgical property of low silicon magnesium pellet[J]. Journal of Iron and Steel Research, 2014, 26(4):7.) [11] 青格勒,吴铿,屈俊杰,等. 不同含镁添加剂对球团矿工艺参数及质量的影响[J]. 钢铁,2013,48(7):17.(QING Ge-le, WU Keng, QUN Jun-jie, et al. Effect of different magnesium additives on process parameters and pellet quality[J]. Iron and Steel, 2013,48(7):17.) [12] 青格勒,吴铿,刘文旺,等. 用秘鲁磁铁矿粉生产球团矿工艺技术研究[J]. 烧结球团,2011,36(6):22. (QING Ge-le, WU Keng, LIU Wen-wang, et al. Study on pelletizing technology with peru magnetite iron ore fines[J]. Sintering and Pelletizing, 2011, 36(6):22.) [13] 朱德庆,虎训,潘建,等. 优化配矿强化西澳超细粒磁铁精矿球团焙烧研究[J]. 工程科学学报,2017,39(5):683.(ZHU De-qing, HU Xun, PAN Jian, et al. Optimization of feed blends to enhance the roasting performance of pellets made from Western Australian ultrafine magnetite concentrate[J]. Chinese Journal of Engineering, 2017, 39(5):683.) [14] 潘建,于鸿宾,朱德庆,等. MgO含量及来源对磁铁精矿球团固结行为的影响[J].中南大学学报(自然科学版),2016,47(9):2914.(PAN Jian, YU Hong-bin, ZHU De-qing, et al. Effect of MgO content and sources on induration behavior of magnetite concentrate pellets[J]. Journal of Central South University(Natural Science), 2016, 47(9):2914.) [15] 信自成,李杰,韩闯闯,等. 镁质熔剂性球团抗压强度研究[J].烧结球团,2018,43(5):56.(XIN Zi-cheng, LI Jie, HAN Chuang-chuang,et al. Study on compressive strength of magnesia fluxed pellets[J]. Sintering and Pelletizing, 2018, 43(5):56.) [16] 李杰,信自成,刘卫星,等. SiO2含量对镁质熔剂性球团性能影响[J].烧结球团,2017,42(4):23.(LI Jie, XIN Zi-cheng, LIU Wei-xing, et al. Influence of SiO2 content on the quality of magnesium fluxed pellets[J]. Sintering and Pelletizing, 2017, 42(4):23.) [17] 李杰,信自成,杨爱民,等.碱度对镁质熔剂性球团性能的影响[J].钢铁,2017,52(7):35.(LI Jie, XIN Zi-cheng, YANG Ai-min,et al. Effect of basicity on quality of magnesium fluxed pellets[J]. Iron and Steel, 2017, 52(7):35.) [18] 李杰,韩闯闯,杨爱民,等. MgO含量对镁质熔剂性球团性能的影响[J].烧结球团,2017,42(2):31.(LI Jie, HAN Chuang-chuang, YANG Ai-min, et al. Effect of MgO on the performance of magnesian fluxed pellets[J]. Sintering and Pelletizing, 2017, 42(2):31.) [19] 田铁磊,李杰,邢宏伟.液相量对高镁碱性球团强度的影响[J].烧结球团,2015,40(3):22.(TIAN Tie-lei, LI Jie, XING Hong-wei. Influence of liquid phase quantity on compressive strength of high magnesia alkaline pellet[J]. Sintering and Pelletizing, 2015, 40(3):22.) [20] 杨福. 碱度和MgO质量分数对球团抗压强度的影响[J]. 中国冶金, 2020, 30(6): 19.(YANG Fu. Effects of basicity and MgO mass fraction on compression strength of pellets[J]. China Metallurgy, 2020, 30(6): 19.)