唐钢新区铁水KR高效脱硫的工业试验研究

Industrial Experiment Study on Hot Metal KR Highly Efficient Desulfurization at Tangsteel New Plant

通过在唐钢新区200 t铁水包中取样,研究了KR脱硫过程中铁水中[S]和脱硫渣中(S)含量的变化规律。结果表明,在KR 10 min的机械搅拌过程中,铁水硫从初始0.038%下降到0.002%,脱硫渣(S)从初始0.028%上升到3.28%。脱硫率从初始68%下降到33%。KR脱硫的限制性环节在后期的7~10 min,这是目前仍尚未明确的问题。为了提高KR处理过程末段脱硫效率,采用了阶跃式变化搅拌速度的工艺思路,并开展工业试验,在不增加搅拌时间的情况下,搅拌速度从90~110 r/min降低至45~90 r/min,脱硫剂用量从8~10 kg/t降至4.0~6.5 kg/t。阶跃控制搅拌速度的KR脱硫模式,在实际生产中具有较强的应用价值。

During KR desulfurization process, the variation of [S] in hot metal and(S) in desulfurization slag is studied accordingly by sampling in the 200 t hot metal ladle at Tangsteel new plant. It shows that, during the 10 minutes of KR stirring process, the sulfur in hot metal decrease from initial 0.038% to 0.002%, and the sulfur in desulfurization slag is increasing from initial 0.028% to 3.28%. while the desulfurization rate keeps decreasing from 68% to 33%. So the limiting link of KR desulfurizing happens at the last 7 to 10 minutes, which not clear in many studies at present. In order to improve the desulfurizing efficiency for the last few minutes, step-changing stirring speed is adopted and applied for the practical industry experiments, the stirring speed decrease from 90-110 r/min to 45-90 r/min, and then the amount of desulfurizer can be reduced from 8-10 kg/t to 4.0-6.5 kg/t without increasing stirring time. So this kind of KR desulfurization model of step-changing stirring speed and immerge depth of impeller has a potential application value for practical industry production.