Experimental study on reactor performance of gas–solids low-velocity fluidized beds--颗粒学报PARTICUOLOGY

Liu, J., & Zhu, J. (2022). Experimental study on reactor performance of gas–solids low-velocity fluidized beds. Particuology, 66, 21-28. https://doi.org/10.1016/j.partic.2021.08.006

Experimental study on reactor performance of gas–solids low-velocity fluidized beds

Jiangshan Liu, Jesse Zhu ^*

Particle Technology Research Centre, Department of Chemical and Biochemical Engineering, The University of Western Ontario, London, Ontario, N6A 3K7, Canada

10.1016/j.partic.2021.08.006

Volume 66, July 2022, Pages 21-28

Received 12 April 2021, Revised 20 June 2021, Accepted 2 August 2021, Available online 2 September 2021, Version of Record 3 November 2021.

E-mail: jzhu@uwo.ca

Highlights

• Reactor performance of low-velocity fluidized beds with superficial gas velocity 0.1–1.2 m/s.

• TFB demonstrates better reactor performance than BFB.

• TFB is more similar to that of a plug flow reactor.

• TFB has higher gas–solids contact efficiency than BFB.

• High ozone conversion takes place in entrance region near the gas distributor.

Abstract

Reactor performance of bubbling fluidized bed (BFB) and turbulent fluidized bed (TFB) was carefully examined and systematically compared using catalytic ozone decomposition as a model reaction, based on a complete mapping of local flow structures and spatial distributions of ozone conversion and solids holdup. TFB clearly has a higher conversion and shows better reactor performance than BFB as a result of the vigorously turbulent flow and the relatively homogeneous gas–solids mixing in TEB. Besides, the intensive interaction between gas and solids in TFB leads to greater gas–solids contact efficiency of TFB over that of BFB. Due to gas bypassing and backmixing caused by bubbling behaviours and two-phase structure, BFB deviates significantly from a plug flow reactor and sometimes from a continuously stirred tank reactor. The flow structures essentially dictate the reactor performance in the low-velocity fluidized beds.

Graphical abstract

Keywords

Bubbling fluidized bed; Turbulent fluidized bed; Conversion distribution; Flow structure; Reactor performance; Gas–solids contact efficiency

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