Residence time of large particles in fluidized beds with non-uniform gas introducing

被引：0
|
作者：
Tian F. [1 ]
Zhu T. [1 ]
Kong D. [1 ]
Lei M. [1 ]
机构：
[1] College of Environmental Science and Engineering, Donghua University, Shanghai
来源：
Huagong Xuebao/CIESC Journal | 2020年 / 71卷 / 04期
关键词：
Experimental investigation; Fluidized bed; Particle; Residence time distribution; Uneven air supply;
D O I：
10.11949/0438-1157.20191359
中图分类号：
学科分类号：
摘要：
The experiment investigated the influence of non-uniform air distribution configuration on the residence time distribution(RTD) of large particles in a fluidized bed with an inclined air distribution plate. The results indicate that, an increase in the discharging velocity makes the E(t) curve more flat and fluctuating, with the mean residence time (MRT) growing exponentially. With an increasing air velocity in the high-gas-flow-rate-zone (HGFRZ), the segregation of tracers is initially dominant and gives way to the mixing process at the late stage. There is an optimal range of the HGFRZ gas velocity for separation. A high air velocity in the low-gas-flow-rate-zone (LGFRZ) induces an intensive mixing and a longer MRT. Additionally, the effects of tracers property are studied, as well. Regarding the particle shape, a spherical and smooth surface is good for the separating and results in a short MRT. As far as the size concerned, its impact couples with that of the density. For the dense particles, a large size causes a short MRT. However, for the light ones, a large size brings about a long MRT. Many characteristics of RTD curves from current works, such as the shape, fluctuation, peak time and value, properly reveal the particle flow and mixing behaviors in fluidized beds. These achievements are supposed to provide tangible references to the mechanism exploring of the internally circulating stream, and the engineering applications of fluidized beds with multiple components. © All Right Reserved.
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页码：1520 / 1527
页数：7
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