Numerical Simulation Of Granular Flow Of Carbon Rotary Kiln Based On The DEM

With the recent rapid development of aluminum industry, the quality of calcinedpetrolem coke which is used for producing prebake carbon slab has also suffered moreand more attention. But domestic quality is not very ideal and there is a certain gap withthe foreign advanced level, which is mainly manifested as the much coal burning loss.Ultimately the reason can be summed up the unreasonable operation parameters of rotarykiln. In the evaluation standard of the calcining quality petroleum coke, material activelayer thickness and the time percentage of material thrown down are two very importantevaluation indexes. Setting the reasonable process parameters can make the active layerthickness of cross section of the rotary kiln and the rolling time percentage morereasonable, and improve the quality of the calcined coke, and achieve the goal of theforeign advanced level.This paper compiles the code of the discrete element method with the help of Cprogram to simulate the movement of petrolem coke. It considers the influence of thediameter and rotating speed on the maximum thickness and the particle velocitydistribution, and compares the simulation results of the discrete element method(DEM)with the experimental data from Li Yong. Comparison results show that the DEMsimulation results are coincide in the experimental data, and the data trend can beexplained reasonably, and verify the effectiveness of the discrete element method formaterial particles. In the analysis of the results, it is found that the active layer thicknessof material cross section of the rotary kiln of presents parabolic trend approximately, andthe thickness of the centre line material reaches the maximum, while at both ends is zero,which meets well with predecessors’ research results. In addition, the growing of therotation speed of the kiln and inner diameter larger can make active layer thicknessbigger. Relatively, the effect of the inner diameter is more apparent. In the active layerthickness, the flow velocity distribution of the active layer and the plunger presents linear distribution approximately, in the border of the two layers, namely the dividing line,which shows no obvious linear trend. Which may be caused by the shearing action forthe different direction of the active layer and the plunger flow area.In exploring the influence factors of rolling time percentage of granular material, itis found that the inclination angle has little effect, and the effect of the rotation speed andthe inner diameter of the kiln is significant. Further study found that when the kilndiameter is small, the enlargement of inner diameter can rapidly improve the rolling timepercentage. When the inner diameter has a certain size, its effect decreased significantly.The results of the analysis can provide reference value for practical operation of rotarykiln.