Numerical study of liquid coverage in a gas–liquid–solid packed bed--颗粒学报PARTICUOLOGY

Du, W., Zhang, L., Lv, S., Lu, P., Xu, J., & Wei, W. (2015). Numerical study of liquid coverage in a gas–liquid–solid packed bed. Particuology, 23, 90-99. https://doi.org/10.1016/j.partic.2014.10.013

Numerical study of liquid coverage in a gas–liquid–solid packed bed

Wei Du^{a b}, Lifeng Zhang ^c, Sha Lv ^b, Panpan Lu ^b, Jian Xu ^b, Weisheng Wei ^b *

a State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, China
b The Key Laboratory of Catalysis, China National Petroleum Corp., China University of Petroleum, Beijing 102249, China
c Department of Chemical and Biological Engineering, University of Saskatchewan, Saskatoon, SK, Canada

10.1016/j.partic.2014.10.013

Volume 23, December 2015, Pages 90-99

Received 29 March 2014, Revised 25 September 2014, Accepted 16 October 2014, Available online 26 May 2015, Version of Record 2 December 2015.

E-mail: weiws@cup.edu.cn

Highlights

• Gas–liquid distribution in a packed bed was simulated using CFD and VOF model.

• Effects of influential parameters on radial liquid distributions and contact areas were studied.

• The number of wetted particles decreased with increasing gas velocity.

• The liquid radial distribution was greatly improved by increasing liquid flow rate.

Abstract

In this work, computational fluid dynamics (CFD) simulations using the volume-of-fluid (VOF) model were employed to investigate the effects of liquid properties, liquid and gas flow rates, and wettability of particles on liquid maldistribution at the microscopic level in a fixed bed reactor. The simulation results show that the number of wetted particles decreases with increasing gas velocity, consequently leading to lower liquid–solid contact areas. The radial liquid distribution is greatly enhanced by increasing the liquid flow rate, whereas the time for the liquid to pass through the whole bed is decreased, as expected. Based on simulation results, it was found that the liquid–solid contact area can be increased by using liquids of high viscosities and more wettable particles. However, the flow-through time increases with increasing liquid viscosity. An increase in the gas density showed a minimal impact on the liquid flow-through time, and the liquid density does not impact the radial liquid distribution or the liquid flow time within a range of liquid densities typically encountered in the petrochemical industry.

Graphical abstract

Keywords

CFD; VOF; Liquid–solid contact area; Radial liquid distribution; Fixed bed

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