铁焦性能的影响因素及富氢高炉使用铁焦的探讨

Influence factors of iron coke properties and discussion on use of iron coke in hydrogen-rich blast furnace

铁焦是一种新型碳铁复合炉料,相比普通焦炭,其具有高反应性,能降低高炉热储备区温度,提高工作效率。铁焦的性能受制备原料的种类、配比和工艺参数等因素的影响。对于高炉富氢冶炼,因其铁矿石还原及成渣过程改变,需要加速初渣熔化和金属铁渗碳过程;而铁焦的气化反应温度低,有利于碳黑的析出和促进金属铁的渗碳,因此将铁焦代替部分焦炭应用于富氢高炉冶炼可以发挥铁焦和氢气的双重节能减排优势。系统讨论了制备因素对铁焦性能的影响,并探讨了铁焦在富氢高炉应用的可行性和优势。结果表明,铁矿粉对铁焦的反应性具有正向催化作用,加入一定配比的黏结剂可使铁焦结构致密,炭化温度会影响铁焦金属化率,适当的炭化时间可提高铁焦抗压强度和反应后强度。部分铁焦代替焦炭应用于富氢高炉,在发挥其高反应性作用的同时,还可以保护焦炭,加速铁水的渗碳过程并改善高炉的透气性。建议深入探索铁焦在富氢高炉内的反应行为和性能演变特点,并结合富氢高炉对铁焦的性能要求和制备铁焦的影响因素,研究适用于高炉富氢冶炼的铁焦制备技术,以推动高炉低碳冶炼技术的实施。

Iron coke is a new type of carbon and iron composite charge.Compared with the ordinary coke,it has high reactivity,can reduce the temperature in the heat reserve zone of blast furnace and promote the working efficiency.The properties of iron coke are affected by the types,proportions and technological parameters of raw materials.Due to the change of iron ore reduction and slagging process,it is necessary to accelerate the melting of primary slag and carburizing of metal iron for hydrogen-rich blast furnace smelting.The gasification reaction temperature of iron coke is low,which is conducive to the precipitation of carbon black and promote the carburizing of metal iron.Therefore,the application of iron coke instead of partial coke in the hydrogen-rich blast furnace smelting can exert the double advantages of energy saving and emission reduction with hydrogen and iron coke.The effect of prepara-tion factors on the properties of iron coke is systematically discussed,and the feasibility and advantages of the appli-cation of iron coke in the hydrogen-rich blast furnace are discussed.The results show that iron ore powder has a positive catalytic effect on the reactivity of iron coke.The structure of iron coke can be densified by adding a certain ratio of binder.The carbonization temperature will affect the metallization rate of iron coke.Appropriate carboniza-tion time can strengthen the compressive strength of iron coke and increase the strength after reaction.Part of iron coke is used instead of coke in the hydrogen-rich blast furnace,which can protect coke,accelerate the carburizing process of hot metal and improve the gas permeability of blast furnace as well as playing its highly reactive role.It is suggested to explore the reaction behavior and performance evolution of iron coke in the hydrogen-rich blast furnace.Combined with the performance requirements of the hydrogen-rich blast furnace and the factors affecting the prepa-ration of iron coke,the preparation technology of iron coke suitable for the hydrogen-rich blast furnace smelting is studied in order to promote the implementation of low carbon smelting technology of blast furnace.