摘要
随着中国“双碳”战略的实施,钢铁行业的节能减排迫在眉睫。氢基还原剂的使用可大幅降低炼铁环节的碳排放。以高磷鲕状赤铁矿为原料制备自熔剂型球团,以氢气为还原剂,采用热重法分析自熔剂型球团在1073 K的还原过程,并用XRD、SEM等方法分析了原矿、自熔剂型球团、还原产物的微观形貌、成分和物相,研究B_(2)O_(3)对自熔剂型球团还原过程的促进作用。结果表明:当球团碱度为2.5时,随着球团中B_(2)O_(3)质量分数的增加,球团的还原度和金属化率先增加后减少,当B_(2)O_(3)质量分数为2%时,还原度和金属化率最高分别达到85.10%和83.99%。这是因为B_(2)O_(3)对球团还原的同时存在促进和抑制的作用。适量的B_(2)O_(3)会破坏矿物的鲕状结构并使球团的孔隙率增加,有利于球团内氢气的扩散,为球团的还原提供了更好的动力学条件。但球团内过量的B_(2)O_(3),会过多消耗球团内的CaO,导致富余的SiO2会与FeO结合形成铁橄榄石,从而阻碍还原。
With the implementation of China's“dual carbon”strategy,energy conservation and emission reduction in the steel industry are urgently needed.Hydrogen-based reducing agents can significantly reduce carbon emissions in the ironmaking process.With the high-phosphorus oolitic hematite used as raw material to prepare self-fluxing pellets and hydrogen gas used as a reducing agent,the reduction process of self-fluxing pellets at 1073 K is analyzed by thermogravimetric analysis.The microstructure,composition,and phase of the original ore,self-fluxing pellets,and reduction products are analyzed by XRD,SEM,and other methods to study the promoting effect in B_(2)O_(3)on the reduction process of self-fluxing pellets.The results show that when the basicity of the pellets is 2.5,the reduction degree and metallization rate of the pellets first increase and then decrease with the increase in B_(2)O_(3)mass fraction in the pellets.When the B_(2)O_(3)mass fraction is 2%,the reduction degree and metallization rate reach the highest of 85.10%and 83.99%,respectively.This is because B_(2)O_(3)has both promoting and inhibiting mechanisms on the reduction of pellets.An appropriate amount of B_(2)O_(3)can destroy the oolitic structure of minerals and increase the porosity of the pellets,which is beneficial to the diffusion of hydrogen gas within the pellets and provides better kinetic conditions for reduction.However,excessive B_(2)O_(3)in the pellets will consume too much CaO,causing the SiO2 to combine with FeO to form fayalite,which hinders the reduction process.
作者
黄记鹏
马江华
杨潮鑫
赵一将
刘昱
李光强
HUANG Jipeng;MA Jianghua;YANG Chaoxin;ZHAO Yijiang;LIU Yu;LI Guangqiang(The State Key Laboratory of Refractories and Metallurgy,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China;Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China;Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China)
出处
《钢铁研究学报》
北大核心
2025年第6期740-750,共11页
Journal of Iron and Steel Research
基金
国家自然科学基金资助项目(52274305)。
作者简介
黄记鹏(2000-),男,硕士生,E-mail:huangjipeng@wust.edu.cn;通信作者:李光强(1963-),男,博士,教授,E-mail:liguangqiang@wust.edu.cn。
