铁矿粉煤基还原回转窑结圈机制  

Ring mechanism of iron ore pulverized coal-based reduction rotary kiln

作　　者：白晨晨 杨广庆 李帅兵 武龙飞 马保良 石焱 BAI Chenchen;YANG Guangqing;LI Shuaibing;WU Longfei;MA Baoliang;SHI Yan(College of Metallurgy and Energy,North China University Science and Technology,tangshan 063210,China;Xingtai Iron and Steel Corp.,Ltd,Xingtai 054027,China)

机构地区：[1]华北理工大学冶金与能源学院,河北唐山063210 [2]邢台钢铁有限责任公司,河北邢台054027

出　　处：《粉末冶金工业》2024年第5期39-48,共10页Powder Metallurgy Industry

基　　金：国家自然科学基金资助项目(52174312);河北省自然科学基金-高端钢铁冶金联合基金项目(E2021209151)

摘　　要：回转窑结圈现象严重影响还原物料的质量,还会降低生产效率,因此有必要探究粉料还原回转窑结圈机制,采取一定的措施来缓解结圈现象。通过选用PB粉和无烟煤为反应原料,得到产物与以Al_(2)O_(3)和SiO_(2)为主要成分的耐火砖发生反应,采取扫描电镜-能谱分析方法对不同温度、配碳量和物料下结圈进行微观结构表征。结果表明:随着温度增加,结圈样品的结构更加紧密,气孔数量及孔径减小,结圈结构中逐渐有白色丝状结构出现。当温度在1 050~1 150℃之间时,结圈结构仍是有小孔存在,当温度升高至1 200℃时,几乎无气孔存在。随着碳氧比增加,结圈物料的孔径逐渐增加,碳氧比从0.75上升至1.75时,结圈物孔径从0.36μm增加至0.87μm,明显可见结圈结构逐渐松散。粒度对物料结圈有明显影响,粒度越大的物料其结圈越不容易,结圈结构也较为松散。选用无烟煤作还原剂时,1号精粉结圈物主要含有铁相、硅酸盐相和铁尖晶石,2号精粉结圈物主要含有铁相和少量氧化铁相以及一些硅酸盐相;选用PB粉作还原铁矿粉时,烟煤结圈物主要含有铁相和硅酸盐相。The phenomenon of rotary kiln ring seriously affects the quality of reducing materials and will reduce production efficiency,so it is necessary to explore the mechanism of powder reduction rotary kiln ring and take certain measures to alleviate this phenomenon.PB powder and anthracite were selected as the raw materials,the products reacted with refractory bricks that have Al_(2)O_(3) and SiO_(2) as the main components,and the microstructure of different temperatures,carbon formulations and lower rings of materials were characterized by scanning electron microscopy-energy spectrum analysis.The results show that with the increase of temperature,the structure of the ring sample become tighter,the number of stomata and pore size decrease,and the white filamentous structure gradually appeares in the ring structure.When the temperature is between 1050-1150°C,the ring structure still has small holes,and when the temperature rises to 1200°C,there are almost no pores.With the increase of carbon-oxygen ratio,the pore size of the ring material gradually increases,and when the carbon-oxygen ratio increases from 0.75 to 1.75,the pore size of the ring material increases from 0.36μm to 0.87μm,and it is obvious that the ring structure is gradually loosened.The particle size has a significant impact on the material ring,the larger the particle size of the material,the more difficult it is to crunch,and the ring structure is relatively loose.When anthracite coal is selected as the reducing agent,the No.1 fine powder circle mainly contains iron phase,silicate phase and iron spinel,and the No.2 fine powder circle mainly contains iron phase and a small amount of iron oxide phase and some silicate phase.When PB powder is selected as reduced iron ore powder,bituminous coal rings mainly contain iron phase and silicate phase.

关 键 词：回转窑 结圈 液相生成 配碳量 微观结构 

分 类 号：TF55[冶金工程—钢铁冶金]