摘要
气基竖炉内设置AGD管道可优化还原气体的分布,但同时对垂直移动床运动行为产生不利影响,因此基于离散单元法(DEM)研究AGD管道对垂直移动床下降速度的影响程度。建立两种竖炉模型分别设置单根和双根AGD管道,利用示踪料层对比分析两种竖炉内垂直移动床料层的运动形态和径向速度分布。结果表明:两种竖炉垂直移动床的上部料层运动形态都呈"直线"型且速度分布均匀;单根AGD管道附近区域料层径向速度分布波动大且中心处运动滞后,双根AGD管道附近区域料层呈"波浪"型且径向速度波动相对较小;两种竖炉内垂直移动床的下部料层皆超前运动形成"漏斗"型,但双根AGD管道竖炉下部料层径向速度分布差异小;对比可知双根AGD管道竖炉内料层下行速度径向分布波动明显较弱,全部还原时间内速度整体分布更加集中。
The AGD(Areal Gas Distribution) pipe arranged in the gas-based shaft furnace can optimize the distribution of the reducing gas but adversely affect the movement behavior of vertical moving bed. Therefore,the influence of AGD pipe on the falling velocity of pellets is studied based on the Discrete Element Method. Two different structural shaft furnace models are established to set single-pipe and double-AGD pipes respectively,and the movement pattern and radial velocity distribution of the vertical moving bed of the two shaft furnaces were compared by using the tracing layer. The results show that the motion patterns of the upper layers in vertical moving bed of the two shaft furnaces are "linear" and the velocity distribution is uniform. The radial velocity distribution of the tracing layer in the vicinity of the single-AGD pipe fluctuates greatly and the motion at the center of the layer is lagging,the pellets layer of the area near the double-AGD pipes is wave-like and the radial velocity fluctuation is relatively small. The lower layers in vertical moving bed of the two shaft furnaces quickly advance to form a "funnel" type,but the difference in the radial velocity distribution of the lower pellet layer is small in the shaft furnace with the double-AGD pipes. Comparative analysis shows that the radial distribution fluctuation of the descending velocity of the pellet layer in shaft furnace with the double-AGD pipes is obviously weak and the overall velocity distribution is more concentrated within the total reduction time.
作者
任素波
张涛
白明华
杨雪辉
马宁
Ren Subo;Zhang Tao;Bai Minghua;Yang Xuehui;Ma Ning(National Engineering Research Center for Equipment and Technology of Cold Strip Rolling, Yanshan University,Qinhuangdao 066004, Hebei)
出处
《烧结球团》
北大核心
2019年第5期50-56,共7页
Sintering and Pelletizing
基金
河北省自然科学基金资助项目(E2017203157,E2018203062)
