%0 Journal Article
%T 回转干馏炉内挡板形状对二元颗粒运动混合的影响
%A 张立栋
%A 韦庆文
%A 王擎
%J 浙江大学学报(工学版)
%D 2018
%R 10.3785/j.issn.1008-973X.2018.08.014
%X 根据回转干馏炉（简称回转炉）内二元颗粒混合时的涡心区的位置，提出在距离回转炉中心21 mm处设置挡板的增混方式.挡板主要依靠推送和抛洒2种作用来增强二元颗粒之间的混合.采用离散单元法，对安装不同形状挡板的回转炉内二元颗粒的运动混合进行数值模拟，研究挡板形状对二元颗粒运动混合的影响.结果表明，挡板边数越多，平均终末卸料角越大.在回转炉运行过程中，当挡板边数为2时，仅存在主体颗粒瀑布流；当挡板边数为1、3、4、∞时，主体颗粒瀑布流和悬空颗粒瀑布流共存.相比于无挡板，在回转炉中安装挡板时，不存在小颗粒集中分布的涡心区，2种颗粒交错分布，颗粒分布更加均匀.当挡板边数从0增加到2时，时均接触数指标M的提高比较明显，从0.288增加到0.424，颗粒的混合质量变好.对于2、3、4、∞边形挡板，时均接触数指标M差别较小，颗粒的混合质量差别较小.</br>Abstract: Accounting to the location of core region in the mixing process of binary particles in a rotary retort, flights were set 21 mm away from the center of the rotary retorts to enhance mixing of particles. The mixing enhancement lies on the pushing and cascading of flights. Discrete element method (DEM) was used to simulate the motion and mixing of binary particles in rotary retorts when flights with different shapes were installed. The influence of the flights' shape on the motion and mixing of binary particles in a rotary retort was analyzed. Results show that the averaged terminal angle of unloading increases as the number of flight's sides increases. When the number of flight's sides is 2, only main cascading curtains exist during the operation of rotary retort. When the number flight's sides is 1, 3, 4 or ∞, both main cascading curtains and hanging cascading curtains exist during the operation of rotary retort. Compared with the rotary retort without flights, the core region where small particles are concentrated disappears in rotary retorts with flights, and the distribution of binary particles is more homogeneous. The increase of averaged contact number index is obvious, and the mixing quality gets better when the number of flight's sides increases from 0 to 2. When the number of flight's sides is 2, 3, 4 and ∞, the values of averaged contact number index are approximative, therefore the mixing qualities are approximative.
%U http://www.zjujournals.com/eng/CN/10.3785/j.issn.1008-973X.2018.08.014