铁水KR搅拌脱硫漩涡形态对脱硫剂颗粒量化扩散行为研究

Study on the quantitative diffusion behavior of desulfurizer particles by the shape of hot metal KR stirring desulfurization vortex

通过KR铁水预脱硫水模型试验,分析探讨了影响KR铁水脱硫动力学的主要因素。研究结果表明,搅拌器转速、搅拌器插入深度、铁水罐装载深度、罐径比对铁水脱硫动力学有明显影响,搅拌器转速140 r/min、搅拌器插入深度213 mm、铁水罐装载深度450 mm、罐径比在0.42时粒子分散性最好。研究发现脱硫剂颗粒分散性最好的区域漩涡深度相对搅拌器深度最优范围在0.96~1.17,漩涡宽度相对搅拌器宽度最优范围在0.66~0.72;粒子分散性相对较好的区域漩涡深度相对搅拌器深度最优范围在0.88~1.37,漩涡宽度相对搅拌器宽度最优范围在0.61~1.20。基于水模型试验结果对KR动力学条件优化进行了工业性试验,优化后搅拌器铁水深脱硫比相较于原搅拌器的66.8%,增加7.2百分点,达到74%;新型四叶搅拌器搅拌时间平均为630 s,搅拌周期缩短18 s;在搅拌周期缩短的情况下,优化后搅拌器脱硫剂消耗量降低1.2%;铁水温降降低0.7℃;二次脱硫率降低2.6百分点,扒渣铁损由1.71 t降至1.39 t,降幅达18.7%。工业性试验表明在深脱硫比例增加的条件下,KR动力学条件优化取得了较好效果。

Through the KR hot metal pre-desulfurization water model test,the main factors affecting the KR hot metal desulfurization kinetics were analyzed and discussed.The research results show that the rotational speed of the agitator,the insertion depth of the agitator,the loading depth of the hot metal tank,and the tank diameter ratio have obvious effects on the kinetics of hot metal desulfurization.The particle dispersion was the best when the rotating speed was 140 r/min,the insertion depth of the agitator was 213 mm,the loading depth of the hot metal tank was 450 mm,and the tank diameter ratio was 0.42.It was found that the optimal range of vortex depth relative to agitator and vortex width relative to agitator was 0.96-1.17 and 0.66-0.72 respectively in the area with the best dispersion of desulfurizer particles.The optimal range of vortex depth relative to agitator depth and vortex width relative to agitator width was 0.88-1.37 and 0.61-1.20 respectively in the area with relatively well dispersion of desulfurizer particles.Based on the results of water model experiments,industrial experiments were carried out to optimize the KR kinetic conditions:compared with the original agitator s 66.8%,the deep desulfurization ratio of hot metal in the optimized agitator increased by 7.2 percentage points to 74%.The average mixing time of the new four blade agitator was 630 s,and the mixing cycle was shortened by 18 s.When the stirring period was shortened,the consumption of desulfurizer in the agitator after optimization was reduced by 1.2%,the temperature drop of molten iron decreased by 0.7℃,the secondary desulfurization rate reduced by 2.6 percentage points,and the iron loss of slag removal was reduced from 1.71 t to 1.39 t,a decrease of 18.7%.Industrial tests show that the optimization of KR kinetic conditions has achieved good results under the condition of increasing the proportion of deep desulfurization.