Hydrodynamic behavior of an internally circulating fluidized bed with tubular gas distributors--颗粒学报PARTICUOLOGY

Zhao, W., Wang, T., Wang, C., & Sha, Z. (2013). Hydrodynamic behavior of an internally circulating fluidized bed with tubular gas distributors. Particuology, 11(6), 664–672. https://doi.org/10.1016/j.partic.2012.05.012

Hydrodynamic behavior of an internally circulating fluidized bed with tubular gas distributors

Wenli Zhao ^{a b}, Tiefeng Wang ^a, Chenjing Wang ^a, Zuoliang Sha ^b *

a Beijing Key Laboratory of Green Reaction Engineering and Technology, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
b Tianjin Key Laboratory of Marine Resources and Chemistry, Tianjin University of Science and Technology, Tianjin 300457, China

10.1016/j.partic.2012.05.012

Volume 11, Issue 6, December 2013, Pages 664-672

Received 21 January 2012, Revised 21 April 2012, Accepted 11 May 2012, Available online 28 February 2013.

E-mail: zsha@tust.edu.cn

Highlights

► The internally circulating fluidized bed with a tubular distributor was studied.

► While varying operating conditions, G_s and γ_DR follow a similar trend, but γ_DR is opposite to γ_DR.

► γ_DR was smaller than 10%, and may be decreased further.

► Correlations were obtained to predict G_s, γ_DR and γ_DR.

Abstract

To better understand the hydrodynamic behavior of an internally circulating fluidized bed, solids holdup in the down-comer (ɛ_sD), solids circulation rate (G_s) and gas bypassing fraction (from down-comer to riser γ_DR, and from riser to down-comer γ_RD) were experimentally studied. The effects of gas velocities in the riser and in the down-comer (U_R and U_D), orifice diameter in the draft tube (d_or), and draft tube height (H_R) were investigated. Experimental results showed that increase of gas velocities led to increase in G_s and γ_DR, and slight decrease in γ_RD. Larger orifice diameter on the draft tube led to higher ɛ_sD, G_s and γ_DR, but had insignificant influence on γ_RD. With increasing draft tube height, both G_s and γ_DR first increased and then decreased, while γ_RD first decreased and then increased. Proposed correlations for predicting the hydrodynamic parameters agreed reasonably well with experimental values.

Graphical abstract

Keywords

Internally circulating fluidized bed; Solids holdup; Solids circulation rate; Gas bypassing fraction

文章导读