Simulation of chemical reaction process in gas-particle CFB downers by anisotropic turbulent mass transfer model

In this study, the mass transfer accompanied by an instantaneous irreversible chemical reaction in a slurry bubble column containing sparingly soluble fine reactant particles has been analyzed theoretically. Based on the penetration theory, combining the cell model, a one-dimensional mass transfer model was developed. In the model, the effects of the particle size and the particle dissolution near the gas-liquid interface on the mass transfer were taken into account. The mass transfer model was solved and an analytical expression of the time-mean mass transfer coefficient was attained. The reactive absorption of SO2from gas mixtures into Mg(OH)2/water slurry was investigated experimentally in a bubble column reactor to validate the mass transfer model. The results indicate that the present model has good predicting performance and could be used to predict mass transfer coefficient for the complicated gas-liquid-solid three-phase system with an instantaneous irreversible chemical reaction.

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Turbulent mass transfer model for the simulation of liquid-solid CFB risers and its verification

Powder Technology ◽

10.1016/j.powtec.2020.09.050 ◽

2021 ◽

Vol 377 ◽

pp. 847-856

Author(s):

Yawen Zhang ◽

Panfeng Ren ◽

Wenbin Li ◽

Kuotsung Yu

Keyword(s):

Mass Transfer ◽

Transfer Model ◽

Mass Transfer Model ◽

Turbulent Mass Transfer

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STUDY OF FLUID DYNAMICS AND SULFUR MASS TRANSFER BETWEEN STEEL AND SLAG IN A LADLE FURNACE CONSIDERING DRAG AND NON-DRAG FORCES

DYNA INGENIERIA E INDUSTRIA ◽

10.6036/10206 ◽

2021 ◽

Vol DYNA-ACELERADO (0) ◽

pp. [ 8 pp.]-[ 8 pp.]

Author(s):

Antonio Urióstegui Hernández ◽

PEDRO GARNICA GONZALEZ ◽

CONSTANTIN ALBERTO HERNANDEZ BOCANEGRA ◽

JOSE ANGEL RAMOS BANDERAS ◽

JOSE JULIAN MONTES RODRIGUEZ ◽

...

Keyword(s):

Fluid Dynamics ◽

Mass Transfer ◽

Chemical Reaction ◽

Steel Slag ◽

Transfer Model ◽

Mass Transfer Model ◽

Argon Gas ◽

Sulfur Transfer ◽

Drag Forces ◽

Constant Rate

In this work fluid dynamics and a basic study of the sulfur transfer at the steel/slag interface in the ladle during argon gas agitation was developed. Mass transfer and chemical reaction models coupled with Computational Fluid Dynamics (CFD) were employed. The multiphasic simulation was solved using the Eulerian model considering drag and non-drag forces, and the flow pattern was validated through Particle Image Velocimetry (PIV) technique. The sulfur transfer rate was tracked by two approximations: (1) unidirectional constant rate Mass Transfer Model (MTM), and (2) unidirectional constant rate Mass Transfer Model coupled with Chemical Reaction Model (MTM+CRM) using Arrhenius equation. It was found that including the non-drag forces affects the fluid dynamics structure. Otherwise, the desulfurization rates increase as the argon gas flow rate increases, finding that the MTM model predicts ~15% less sulfur in the steel than the MTM+CRM, whose results were compared with plant measurements reports.

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