LF热态钢渣循环利用炉渣成分控制

Slag Composition Control for the Re-Utilization of LF Hot Steel Slag

为了实现LF热态钢渣的循环利用,对目前武钢LF热态钢渣两次循环利用工艺中精炼渣的组成、脱硫能力及吸收夹杂能力的变化进行了分析研究。结果表明,LF热态钢渣循环利用后钢水的脱硫率可以达到90%以上,精炼终点w([S])可以达到0.001%的水平;相对于未循环工艺,钢中w(T[O])减少17.50×10-6,w([N])减少17.00×10-6,夹杂物数量减少4.47个/mm2。根据两次热循环利用结果得出:通过控制回收的渣量及补加石灰的量,可保证循环后初始炉渣中的w((S))小于0.20%,终渣碱度(w(CaO)/w(SiO2))在12.00～20.00范围,w(CaO)/w(Al2O3)为1.75～2.00,从而使精炼渣的脱硫效率、w((S))/w([S])不受循环次数的限制。

In order to realize the re-utilization of LF hot steel slag,the change of LF refining slag composition,desulphurizing capacity and ability for absorption of inclusion was investigated in the currently process of hot re-utilization in WISCO.The results show that,after re-utilization of LF hot steel slag,desulfurization efficiency can reach more than 90%,sulphur content of molten steel can reach 0.001% in the end of refining,the total oxygen in molten steel can reduce 17.50×10-6,nitrogen content can reduce 17.00×10-6,inclusion＇s content can reduce 4.47 per square millimeter relative to not cycle.According to the refining effect after two cycle,through controlling the slag amount of recycling and lime amount of replenishing,the following results can be obtained,such as the sulphur content in the initial slag less than 0.20%,the basicity of final slag in the range of 12.00-20.00,w（CaO）/w（Al2O3） in the range of 1.75-2.00.The desulfurization efficiency and w（（S））/w（[S]） are not limited by cycle times.