基于三维离散元法的罐式炉排料运动行为

Discharging behavior of petroleum coke in vertical shaft calciner based on three-dimensional discrete element method

罐式炉排料过程中石油焦颗粒运动行为对煅后焦的质量至关重要。基于离散元法,建立罐式炉内石油焦排料过程的颗粒尺度运动行为的三维数学模型,并通过1/15比例的冷态模型实验验证离散元法模拟的可靠性,研究料罐内固体石油焦颗粒的运动模式、颗粒间相互作用应力及力链分布特性。结果表明:离散元法模拟能很好的再现实验结果;石油焦颗粒在料罐内的加热带区域基本符合活塞流的运动特征,在冷却水套区域呈漏斗流的运动特征;料罐内石油焦颗粒间的作用力分布不均匀,强力链主要分布在料罐的中下部区域以及冷却水套区域。

The descending behavior of petroleum coke in vertical shaft calciner （VSC） plays an important role in the quality of calcined petroleum coke. A three-dimensional（3D） mathematical model for the discharging behavior of petroleum coke in the VSC was established. Using this model, the motion trajectory of petroleum coke particles, and the distribution of stress and the contact force chain between particles was investigated. Moreover, the reliability of discrete element method （DEM） simulation was verified by 1/15-scale cold physical model experiment. The DEM simulation results agree very well with the experimental results. The petroleum coke flow in the heating zone of pot basically accords with the plug flow, and it presents a funnel flow in the cooling jacket region. The force distribution among the petroleum coke particles is not uniform and the strong chain is mainly distributed in middle and bottom of pot, especially the wall of the cooling water jacket area.