Simulation of Heterogeneous Structure in a Circulating Fluidized-Bed Riser by Combining the Two-Fluid Model with the EMMS Approach

Because of the continuous increase in the amount of plastic waste, catalytic cracking is an interesting method that could be used to convert heavy oil from thermal cracking of plastic waste into fuel. The objective of this study was to investigate the hydrodynamic behavior and the performance of catalytic cracking of heavy oil in a circulating fluidized bed reactor using computational fluid dynamics. The two– fluid model incorporated with the kinetic theory of granular flow was applied to predict the hydrodynamic behavior with a reactive flow. Three reactor geometries were studied, which included a conventional riser, tapered–out riser, and tapered–in riser. The four–lump kinetic model was used to describe the catalytic cracking of heavy oil from waste plastic. A core–annulus flow pattern was found in the three reactor geometries. The solid fraction distribution of the tapered reactor was found to be more uniform than that of the conventional riser. The tapered–in riser showed the highest heavy oil conversion with the lowest gasoline selectivity. However, the heavy oil conversion and gasoline selectivity of the conventional and tapered–out reactors were not significantly different.

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CFD Modeling of Microwave-Assisted Fluidized Bed Drying of Moist Particles Using Two-Fluid Model

Drying Technology ◽

10.1080/07373937.2011.642913 ◽

2012 ◽

Vol 30 (4) ◽

pp. 362-376 ◽

Cited By ~ 15

Author(s):

M. Ranjbaran ◽

D. Zare

Keyword(s):

Fluidized Bed ◽

Fluid Model ◽

Cfd Modeling ◽

Microwave Assisted ◽

Fluidized Bed Drying ◽

Two Fluid Model ◽

Two Fluid

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Two-Fluid Model Simulations of the National Energy Technology Laboratory Bubbling Fluidized Bed Challenge Problem

Industrial & Engineering Chemistry Research ◽

10.1021/acs.iecr.5b04511 ◽

2016 ◽

Vol 55 (17) ◽

pp. 5063-5077 ◽

Cited By ~ 14

Author(s):

Musango Lungu ◽

Haotong Wang ◽

Jingdai Wang ◽

Yongrong Yang ◽

Fengqiu Chen

Keyword(s):

Fluidized Bed ◽

Fluid Model ◽

Energy Technology ◽

Model Simulations ◽

Bubbling Fluidized Bed ◽

Two Fluid Model ◽

Two Fluid

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Simulation Study of Gas-Solid Macro-Mixing Characterization in Small Fixed-Fluidized Bed Reactor

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.236-238.1537 ◽

2011 ◽

Vol 236-238 ◽

pp. 1537-1545

Author(s):

Wen Jing Liu ◽

Hui Zhao ◽

Chao He Yang ◽

Hong Hong Shan

Keyword(s):

Fluidized Bed ◽

Raw Materials ◽

Fluid Model ◽

Structural Parameters ◽

Flow Behavior ◽

Fluidized Bed Reactor ◽

Operating Conditions ◽

Laboratory Evaluation ◽

Two Fluid Model ◽

Two Fluid

In fixed-fluidized bed reactor, laboratory evaluation of different catalyst, raw materials and process parameters can be implemented, so it has wide applications in the refining process. In this study, we focused on small fixed-fluidized bed reactor, using Eulerian-Eulerian two-fluid model, simulated the gas-solid flow behavior in it. Gas residence time distribution was measured in order to characterize macro-mixing. At the same time, by changing the reactor structure and operating conditions, we studied their effects on gas-solid macro-mixing characterization. The results show that the effects of structural parameters are larger than operating conditions, and different parameters have different effects. Different parameters can be adjusted to change the gas-solid macro-mixing characterization in small fixed-fluidized bed reactor. Therefore, the small fixed-fluidized bed reactor can provide better results in more application areas.

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