Process intensification of SO2/CO2 co-capture using microscale vortex flow contactor: Mass transfer behaviors, performance modeling, and flow simulation

This theoretical investigation analyzed the three-dimensional momentum and mass transfer characteristics arising from the multiple inlets and single outlet in micro chamber which consists of a right square prism, an octagonal prism or a cylinder. The effects of various geometric parameters, inlet velocities, and the types of lamination on the mixing characteristics were investigated, and the results were presented in terms of flow fields, concentration profiles, and mixing index. Numerical results indicated that vortex flow and numbers of inlets dominate the mixing index. At larger Taylor number, more inertia caused the powerful vortex flow in the chamber, and the damping effect on diffusion was diminished, which then increased the mixing performance. Furthermore, passive micromixers utilizing hybrid laminations showed better mixing results than those with parallel laminations.

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Applications of an Euler aerodynamic method to free-vortex flow simulation

Journal of Aircraft ◽

10.2514/3.45964 ◽

1990 ◽

Vol 27 (11) ◽

pp. 941-949 ◽

Cited By ~ 1

Author(s):

P. Raj ◽

J. M. Keen ◽

S. W. Singer

Keyword(s):

Vortex Flow ◽

Flow Simulation ◽

Free Vortex ◽

Aerodynamic Method

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Effect of Different Configurations on Bubble Cutting and Process Intensification in a Micro-Structured Jet Bubble Column Using Digital Image Analysis

Processes ◽

10.3390/pr9122220 ◽

2021 ◽

Vol 9 (12) ◽

pp. 2220

Author(s):

Guanghui Chen ◽

Zhongcheng Zhang ◽

Fei Gao ◽

Jianlong Li ◽

Jipeng Dong

Keyword(s):

Mass Transfer ◽

Image Analysis ◽

Flow Field ◽

Digital Image ◽

Bubble Size ◽

Digital Image Analysis ◽

Liquid Velocity ◽

Bubble Column ◽

Process Intensification ◽

Interfacial Area

An experimental study was conducted in this work to investigate the effect of different configurations on bubble cutting and process intensification in a micro-structured jet bubble column (MSJBC). Hydrodynamic parameters, including bubble size, flow field, liquid velocity, gas holdup as well as the interfacial area, were compared and researched for a MSJBC with and without mesh. The bubble dynamics and cutting images were recorded by a non-invasive optical measurement. An advanced particle image velocimetry technique (digital image analysis) was used to investigate the influence of different configurations on the surrounding flow field and liquid velocity. When there was a single mesh and two stages of mesh compared with no mesh, the experimental results showed that the bubble size decreased by 22.7% and 29.7%, the gas holdup increased by 5.7% and 9.7%, and the interfacial area increased by more than 34.8% and 43.5%, respectively. Significant changes in the flow field distribution caused by the intrusive effect of the mesh were observed, resulting in separate liquid circulation patterns near the wire mesh, which could alleviate the liquid back-mixing. The mass transfer experiment results on the chemical absorption of CO2 into NaOH enhanced by a mass transfer process show that the reaction time to equilibrium is greatly reduced in the presence of the mesh in the column.

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Mass transfer in falling film microreactors: measurement techniques and effect of operational parameters

Reviews in Chemical Engineering ◽

10.1515/revce-2018-0065 ◽

2019 ◽

Vol 0 (0) ◽

Author(s):

Ali Alhafiz Mohammed ◽

David Lokhat

Keyword(s):

Mass Transfer ◽

Measurement Techniques ◽

Process Intensification ◽

Liquid Films ◽

Falling Film ◽

Operational Parameters ◽

Transfer Enhancement ◽

Mass Transfer Enhancement ◽

The Relationship ◽

Common Target

Abstract Falling film microreactors have contributed to the pursuit of process intensification strategies and have, over the years, been recognized for their potential in performing demanding reactions. In the last few decades, modifications in the measurement techniques and operational parameters of these microstructured devices have been the focus of many research studies with a common target on process improvement. In this work, we present a review dedicated to falling film microreactors, focusing on the recent advances in their design and operation, with particular emphasis on mass transfer enhancement. Analysis of the recent techniques for the measurement of mass transfer as well as the operational parameters used and their effect on the target objective, particularly in the liquid phase (being the limiting phase reactant), are included in the review. The relationship between the hydrodynamics of falling thin liquid films and the microreactor design, the discrepancies between measured and model results, the major challenges, and the future outlook for these promising microreactors are also presented.

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Pulsed Multiphase Flows—Numerical Investigation of Particle Dynamics in Pulsating Gas–Solid Flows at Elevated Temperatures

Processes ◽

10.3390/pr8070815 ◽

2020 ◽

Vol 8 (7) ◽

pp. 815

Author(s):

Arne Teiwes ◽

Maksym Dosta ◽

Michael Jacob ◽

Stefan Heinrich

Keyword(s):

Mass Transfer ◽

Heat And Mass Transfer ◽

Multiphase Flows ◽

Gas Flow ◽

Elevated Temperatures ◽

Process Intensification ◽

Particle Dynamics ◽

Transport Processes ◽

Pulse Combustion ◽

New Processing

Although the benefits of pulsating multiphase flows and the concomitant opportunity to intensify heat and mass transfer processes for, e.g., drying, extraction or chemical reactions have been known for some time, the industrial implementation is still limited. This is particularly due to the lack of understanding of basic influencing factors, such as amplitude and frequency of the pulsating flow and the resulting particle dynamics. The pulsation generates oscillation of velocity, pressure, and temperature, intensifying the heat and mass transfer by a factor of up to five compared to stationary gas flow. With the goal of process intensification and targeted control of sub-processes or even the development of completely new processing routes for the formation, drying or conversion of particulate solids in pulsating gas flows as utilized in, e.g., pulse combustion drying or pulse combustion spray pyrolysis, the basic understanding of occurring transport processes is becoming more and more important. In the presented study, the influence of gas-flow conditions and particle properties on particle dynamics as well as particle residence time and the resulting heat and mass transfer in pulsating gas–solid flows are investigated.

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