Hydrodynamic characteristics of a rectangular gas-driven inverse liquid-solid fluidized bed  

作　　者：Yicheng Deng Keying Ma jaqi Huang Yuanyuan Shao Jesse Zhu 

机构地区：[1]School of Chemical Engineering and Technology,Tianjin University,Tianjin,300072,China [2]Department of Chemical and Biochemical Engineering,Western University,London,Ontario,N6A3K7,Canada [3]Institute of Shaoxing,Tianjin University,Zhejiang,312300,China [4]Nottingham Ningbo China Beacons of Excellence Research and Innovation Institute,The University of Nottingham Ningbo China,Ningbo,Zhejiang.315100,China

出　　处：《Particuology》2023年第7期86-96,共11页颗粒学报（英文版）

摘　　要：The hydrodynamic characteristics of a rectangular gas-driven inverse liquid-solid fluidized bed(GDFB)using particles of different diameters and densities were investigated in detail.Rising gas bubbles cause a liquid upflow in the riser portion,enabling a liquid downflow that causes an inverse fluidization in the downer portion.Four flow regimes(fixed bed regime,initial fluidization regime,complete fluidization regime,and circulating fluidization regime)and three transition gas velocities(initial fluidization gas velocity,minimum fluidization gas velocity,and circulating fluidization gas velocity)were identified via visual observation and by monitoring the variations in the pressure drop.The axial local bed voidage(e)of the downer first decreases and then increases with the increase of the gas velocity.Both the liquid circulation velocity and the average particle velocity inside the downer increase with the increase of the gas velocity in the riser,but decrease with the particle loading.An empirical formula was proposed to successfully predict the Richardson-Zaki index“n”,and the predicted e obtained from this formula has a±5%relative error when compared with the experimental e.

关 键 词：Gas-driven Inverse fluidized bed Flow regime Average particle velocity Liquid circulation velocity Bed voidage 

分 类 号：O35[理学—流体力学]