COREX竖炉炉料透气性试验研究

Experiment and research on coke and ore permeability of the shaft for COREX

炉料透气性直接影响竖炉还原金属化率,从而影响焦炭使用比例。实验室透气性试验表明,不论是何种加料方式,随着气体流量的增加,压力降均会明显增加;同一气体流量的条件下,矿中小块焦量的增加,料柱的压力降降低;在较高的流量条件下,小块焦的影响变得更明显。焦层高度的降低导致整个压力降的增加;在料床孔隙率、高度、填料直径和气体密度恒定条件下,气体流速的平方与压力降呈现较好的线性关系。生产数据表明,小块焦的使用能够有效降低焦比。竖炉焦炭取样分析表明,竖炉焦炭体积比要适量。

Coke and ore permeability directly influents metallization rate of reduction shaft, consequently influents coke rate. Experiment of coke permeability in lab showed no matter what filling mode, with increasing gas flow rate the pressure drop improved obviously. Under the identical gas flow rate conditions the pressure drop decreased with rising nut coke rate in the ore-coke mixture. The effect became more remarkable at higher flow rate. Decrease of coke layer thickness caused by low coke rate leaded to increasing of the pressure drop. It could find a good linear dependence of pressure drop on the square of gas velocity for constant packaged voidage, height, equivalent diameter and gas density. Analysis of the production data indicated use of nut coke had a good effect on decrease of coke rate. The rate of coke bulk to ore bulk from the shaft was one of the key factors infecting coke rate. Investigation of quality index of coke from the shaft showed appropriate coke bulk rate was very important.