摘要
转底炉处理含锌粉尘工艺存在高锌原料无法充分脱锌的问题。为此,本文通过对现场金属化球团产品进行剖析,探讨锌残留的原因;研究外加气流对还原过程中锌和铁反应行为的影响,具体探究N_(2)流速、CO含量对金属化团块还原效果的影响。结果表明:还原焙烧过程中生成的铁连晶和低熔点化合物堵塞了孔隙,阻碍了锌的挥发,使锌以Zn和ZnO的形式附着在铁连晶周围;当氮气流速从0提高到6 m/s时,脱锌率从50.83%增长至93.19%,金属化率从74.69%降低至67.92%;当CO体积分数从0增长到40%时,脱锌率均维持在90%以上,金属化率从68.30%增长到85.77%,说明还原性气流可以促进锌的挥发,同时提高金属化率。气流强化脱锌机理分析表明,在无气流条件下,液相产生或者铁连晶长大阻碍了锌的挥发通道,导致锌在团块内部富集,而外加还原性气流能够提高锌挥发的速度,促进锌的挥发过程。
There is a problem that high zinc raw materials cannot be fully dezincized in the process of rotary hearth furnace to treat zinc-containing dust,so the on-site metallized pellet products is analyzed to discuss the causes of zinc residue.The effects of applied airflow on the reaction behavior of zinc and iron during the reduction process are studied,and the effects of N_(2) flow rate and CO content on the reduction effect of metallized agglomerates are investigated specifically.The results show that the ferrocrystals and low-melting compounds generated during the reductive roasting process block the pores and hinder the volatilization of zinc,so that the zinc attaches to the ferrocrystals in the form of Zn and ZnO.When the nitrogen velocity is increased from 0 to 6 m/s,the dezincification rate is increased from 50.83%to 93.19%,and the metallization rate is decreased from 74.69%to 67.92%.When the CO volume fraction is increased from 0 to 40%,the dezincification rate is remained above 90%,and the metallization rate is increased from 68.30%to 85.77%,indicating that the reducing airflow could promote the volatilization of zinc and improve the metallization rate.The analysis of the mechanism of airflow-enhanced dezincification show that the formation of liquid phase or the growth of iron crystals hinders the volatilization channel of zinc under the condition without airflow,resulting in the enrichment of zinc in the agglomerate,while the external reducing airflow could increase the rate of zinc volatilization and promote the volatilization process of zinc.
作者
陈铁军
金路恒
万军营
郑锡瀚
周仙霖
刘佳文
CHEN Tiejun;JIN Luheng;WAN Junying;ZHENG Xihan;ZHOU Xianlin;LIU Jiawen(Wuhan University of Science and TechnologySchool of Resources and Environmental Engineering,Wuhan 430081,Hubei,China;Wuhan University of Science and TechnologyHubei Province Key Laboratory for Efficient Utilization and Agglomeration of Metallurgic Mineral Resources,Wuhan 430081,Hubei,China)
出处
《烧结球团》
北大核心
2025年第3期132-140,148,共10页
Sintering and Pelletizing
基金
广西科技重大专项资助项目(桂科AA24263047)。
关键词
含锌粉尘
脱锌
转底炉
直接还原
冶金固废
zinc-containing dust
dezincification
rotary hearth furnace
direct reduction
metallurgical solid waste
作者简介
陈铁军(1973-),男,博士,教授,从事复杂铁矿分选、烧结球团、直接还原方面的研究;通信作者:万军营(1992-),男,博士,讲师,从事烧结球团及直接还原方面的研究。
