变径炭素回转窑内物料平均停留时间的计算

在前人厚度变化公式基础上推导出适用于窑尾扩径和增设翻料装置的炭素回转窑内物料平均停留时间的计算公式，同时建立了实验室回转窑模型，进行了冷态实验。将物料停留时间的计算值与变径回转窑模型实验测试值作了比较。结果表明，公式计算值与实验测试值比较吻合，误差范围在-15％～12％内，并且计算中不需要引入修正系数；回转窑转速和斜度的增加均使物料平均停留时间缩短，而窑尾挡料圈高度的增加可以使平均停留时间缩短，也可以使平均停留时间延长。

Calculation of mean residence time of solids in variable diameter carbon rotary kiln

Based on the axial bed depth model of straight rotary kiln proposed by prior researchers，the equation of mean residence time of solids in carbon rotary kiln with variable diameter and turn-down rig was developed. Cold experiments were carried out on a laboratory rotary kiln under ambient conditions. The comparison between calculated results and experiment data showed that calculated results of the residence time of solids agreed well with measurements and the prediction error varied in a small range of -15%—+12%. No fitting parameter was necessary. The mass flow rate of solids increased and the mean residence time decreased with increasing kiln rotation speed and kiln slope. The mass flow rate of solids increased and the mean residence time might possibly decrease or increase with increasing dam height at the feed end.