高硫铁精矿“一步法”直接还原新工艺

来源期刊：中南大学学报(自然科学版)2002年第1期

论文作者：朱德庆 邱冠周 潘健

文章页码：21 - 24

关键词：高硫铁精矿;直接还原;预热球团;脱硫;活化能

Key words：iron concentrate containing high sulphur; direct reduction; preheated pellets; desulphurization; activation

摘    要：当铁精矿铁品位为69.52%,含硫0.91%时,采用预热球团“一步法”直接还原新工艺,在配入0.2%添加剂K2、预热温度950℃、预热时间25 min的条件下强化球团脱硫,脱硫率为97.1%,预热球团矿残硫含量为0.030%,球团矿强度达1 083 N/个;添加剂K2的作用机理为:其在受热过程中分解,释放活性氧,使脱硫反应的表观活化能由不加添加剂的53.6 kJ/mol下降到44.04 kJ/mol,有利于脱硫反应的进行.脱硫后的预热球团矿在还原温度为1 050℃、还原时间为2 h、球煤质量比为1∶2的条件下,在马弗炉内还原,得到直接还原铁(DRI)的质量指标为:全铁TFe92.24%,金属化率η(Fe) 95.32%,S 0.014%,P 0.004%,该DRI可作为电炉冶炼优质钢和特殊钢的理想原料.该工艺扩大了直接还原工艺对原料的适应性,有利于直接还原工艺的推广应用,有广阔的应用前景.

Abstract: Green pellets containing 0.2% additive agent K2, assaying 69.52% Fe and 0.91% S, were preheated at 950℃for25 minutes, the desulfurization of the pellets was improved by adding agentK2, desulfurization rate of 97.1% being achieved, the compressive strength reached 1083 Nper preheated pellets containing0.030% sulphur. The mechanism of K2 for improving desulfurization was demonstrated as follows: active oxygen was released through the decomposition of 0.2% K2 inside pellets, the apparent activation energy of desulfurization was decreased from 53.6 kJ/mol to 44.04 kJ/mol. Desulfurized preheated pellets were directly reduced inmuff furnace with charged reductant coal at1∶2 of the mass ratio of pellet to coal at 1 050℃for 2 h, directly reduced iron(DRI) assaying 92.4% total iron, 95.32%metallization degree, 0.014% sulphur and 0.004% phosphor was manufactured, which is the ideal burden for making quality and special steel by electric arc furnace. The feasibility of direct reduction to the raw materials is enhanced,which will bring a prosperous future for the spreading of direct reduction processes.

基金信息：国家教育部高等学校优秀青年教师教学科研奖励基金资助项目