Abstract：Since May 2019,the proportion of pellets fed has been successfully increased from 25% to 50%-70% on the 5 500 m3blast furnace in Shougang Jingtang Iron and Steel Co.,Ltd. The pre iron system has not only reduced the emission of pollutants such as particulate matter, SO2 and NOx by 24%, the emission of CO2 per ton of iron by 10%, but also the slag ratio has reduced from 300 kg/t to 210 kg/t, which greatly promoted the improvement of blast furnace smelting level. The influence of slag ratio on the main parameters of blast furnace smelting is studied, which can provide technical reference for blast furnace smelting with low slag iron ratio in the future.It is found through the statistics of production data that after the slag iron ratio decreases from 300 kg/t to 230 kg/t, on the one hand, the main indicators have been significantly improved. The utilization coefficient has been increased from 2.25 to more than 2.50, the permeability index has been increased from 4 100 to more than 4 300, the coke ratio has been reduced from 295 kg/t to less than 265 kg/t, and the coal ratio has been increased to 200-220 kg/t. On the other hand, the reduction of slag ratio also brings about the reduction of slag desulfurization and alkali discharge capacity. Under the conditions of 3.80-3.90 kg/t sulfur load and 2.60 kg/t alkali load, in order to meet w([S])<0.050% in molten iron and the slag alkali discharge rate is greater than 75%, the optimal slag iron ratio control center line of 230 kg/t is proposed.In the future, if the the slag ratio is further reduced, it should start with reducing harmful elements and optimizing slag composition to minimize the circulation and enrichment of harmful elements in the furnace, so as to ensure that the furnace conditions are high and stable.In addition, after the slag ratio decreases significantly, the flow rate of molten iron increases significantly, and the tapping times decrease. The tapping system should be optimized and adjusted in time to meet the smelting requirements of low slag ratio.
[1] 张利娜.钢铁行业低碳技术应用及发展研究[J].冶金能源,2023,42(2):3.(ZHANG L N. Application and development research of low carbon technology in iron and steel industry[J]. Energy for Metallurgical Industry,2023, 42(2):3.) [2] 路明,陈小燕,王兴锋,等.钙质添加剂对碱性球团性能的影响[J].冶金能源,2022,41(2):19.(LU M,CHEN X Y,WANG X F,et al. Effect of calcium additives on the performance of calcium fluxed iron ore pellets[J]. Energy for Metallurgical Industry,2022,41(2):19.) [3] KOKI T,YUSUKE K,TOSHIYUKI H,et al. Optimization of coke mixed charging based on discrete element method[J]. ISIJ International,2017,57(10):1084. [4] 赵沛,董鹏莉.碳排放是中国钢铁业未来不容忽视的问题[J].钢铁,2018,53(8):8.(ZHAO P,DONG P L.Carbone-mission cannot be ignored in future of China steel industry[J]. Iron and Steel,2018,53(8):8.) [5] 王海洋,张建良,王广伟,等.铁前系统的二氧化碳减排技术浅析[J].中国冶金,2018,28(1):1.(WANG H Y,ZHANG J L,WANG G W,et al. Analysis of carbon dioxide emission reduction before ironmaking[J]. China Metallurgy,2018,28(1):1.) [6] 牛群,邹忠平,王刚,等. 高炉炉缸死料柱受力分析及影响因素[J]. 中国冶金,2023,33(2):55.(NIU Q,ZOU Z P,WANG G,et al. Force analysis and influence factors of deadman in blast furnace hearth[J]. China Metallurgy,2023,33(2):55.) [7] 姜喜远. 高碱度CaO-Al2O3-SiO2-MgO-TiO2-Na2O六元渣系脱硫性能的研究[D]. 赣州:江西理工大学,2016.(JIANG X Y. Study on Desulfurization Performance of High Alkalinity CaO-Al2O3-SiO2-MgO-TiO2 Na2O Six Component Slag System[D]. Ganzhou:Jiangxi University of Science and Technology,2016.) [8] 孙宝银. 改善高炉渣系的生产操作实践[J]. 炼铁技术通讯,2007(9):16.(SUN B Y. Production practice of improving blast furnace slag system[J]. Ironmaking Technical Communication,2007(9):16.) [9] 田坚,冯可芹,严子迪,等. 缓冷与水淬高钛型高炉渣制备微晶泡沫玻璃的对比研究[J]. 钢铁钒钛,2020,41(5):96.(TIAN J,FENG K Q,YAN Z D,et al. Comparative study on preparation of foam glass-ceramics from slow-cooling and water-quenched high titanium blast furnace slag[J]. Iron Steel Vanadium Titanium,2020,41(5):96.) [10] 刘杰,赵东明,等. 鞍钢高炉低镁渣冶炼技术研究与应用[J]. 钢铁,2018,53(3):22.(LIU J,ZHAO D M,et al. Research and application of blast furnace′s low(MgO) slag in Ansteel[J]. Iron and Steel,2018,53(3):22.) [11] 姜鑫,高炉炉料中合理利用含MgO原料的基础理论研究[D]. 沈阳:东北大学,2008.(JIANG X. Fundamental Study on Reasonable Utilizating of Raw Material Containing MgO in the Burden of BF[D]. Shenyang:Northeastern University,2008.) [12] KIMMO K,TIMO P,JARMO L,et al. (STSI-156)Modelling and aimulation of blast furnace process for switch from sinter to operation[C]//4th International Conference on Modelling and Simulation of Metallurgical Processes in Steelmaking. Dusseldorf:METEC,2011:1. [13] TIMO P,KIMMO K,JARMO L,et al. Experience of full scale research test with 100% pellet blastfurnace operation in ruukkiauthors[C]//6th European Coke and Ironmaking Congress. Dusseldorf:METEC,2011:11. [14] 杜鹤桂,车传仁. 软熔带对高炉强化冶炼的影响[J].钢铁,1980,15(4):21.(DU H G,CHE C R. Influence of softening-melting zone on the hard driving of blast furnace[J]. Iron and Steel,1980,15(4):21.) [15] 赵晨光. CaO-SiO2-MgO-Al2O3-FeO系高炉中间渣流动性能与结构[D]. 鞍山:辽宁科技大学,2019.(ZHAO C G. Fluidity and Structure of CaO-SiO2-MgO-Al2O3-FeO Bosh Slag in Blast Furnace[D]. Anshan:University of Science and Technology Liaoning,2019.) [16] 吴胜利,王筱留. 钢铁冶金[M]. 北京:冶金工业出版社,2019.(WU S L,WANG X L. Iron and Steel Metallurgy[M].Beijing:Metallurgical Industry Press,2019.) [17] 常治宇,张建良,许仁泽,等. 酒钢高炉炉渣冶金性能评价与炉况分析[J]. 钢铁研究,2017(6):26.(CHANG Z Y,ZHANG J L,XU R Z,et al. Evaluation of metallyrgical properties of blast furnace slag of JISCO and analysis of furnace condition[J]. Research on Iron and Steel,2017(6):26.) [18] 王鑫杰. 高炉冶炼过程中渣性能变化研究[D]. 武汉:武汉科技大学,2021.(WANG X J. Study on Performances Change of Slag in the Process of Blast Furnace Smelting[D]. Wuhan:Wuhan University of Science and Technology,2021.)
2023, Vol. 58 
