COREX竖炉结瘤对物料运动行为影响的DEM模拟

 为考察COREX预还原竖炉内部结瘤对物料行为的影响,利用离散单元法(DEM)研究了炉内不同位置结瘤对物料运动流型、颗粒应力的影响,并探究了排料速率对炉内物料运动行为的改善作用。模拟结果表明,竖炉围管区发生结瘤,直接影响结瘤附近物料运动轨迹,导致物料运动流型发生变化;同时,相较正常工况,炉内物料间作用力明显增加。当竖炉导流锥产生结瘤时,物料运动流型也明显改变,并且颗粒在结瘤位置下方存在偏析现象;与围管结瘤相比较,炉内颗粒间作用力进一步增加;通过对瘤下方螺旋排料器转速提升,颗粒间作用力显著降低,基本与顺行状态下保持一致。相关研究可为COREX竖炉的优化操作提供指导和理论依据。

Effect of scaffolding on solid flow in COREX shaft furnace by discrete element simulation method

A three-dimensional DEM-based model was used to investigate the effect of scaffolding on the burden behavior such as the solid flow pattern and the interactive force in COREX shaft furnace. The improvement of the discharge rate on the solid flow under scaffolding conditions was also explored. The results confirm that the scaffolding occurred near the bustle pipe zone would directly affect the movement trajectory of the burden, resulting in the changes of solid flow pattern. Meanwhile, the interactive force was increased obviously compared to the normal condition. The solid flow pattern was also changed significantly when the scaffolding was generated in the guiding cone, and the particle segregation can be observed under the scaffolding. Comparing with the condition where scaffolding was generated near the bustle pipe zone, the interactive force was enhanced further. The force between the particles was decreased dramatically by increasing the speed of screw under the scaffolding, and the probability density distribution of interactive force shows a similar tendency as the normal condition. The findings of this work can provide guidance and theoretical basis for the optimized operation of COREX shaft furnace.