Correlation between mass transfer coefficient kLa and relevant operating parameters in cylindrical disposable shaken bioreactors on a bench-to-pilot scale

Microfluidic devices are used in several engineering fields ranging from biomedical to chemical to engineering for applications such as micro reactor, target molecular enriching and cell capturing. With regard to related applications, microfluidic devices offer advantages such as high surface area to volume ratio, increased mass transfer coefficient and portability in addition to their requirement of low analytes. Affinity based microfluidic devices with microscale posts have high compactness and mass transfer coefficient. In order to maximize the benefits offered by employing microfluidic devices, it is important to apply parametric study in the device designing work. This study is aimed at studying the operating and geometric parameters of microfluidic devices with square/rectangular microscale posts. The geometric parameters, such as aspect ratio of the microposts used, could possibly decide the performance of the device. Operating parameters studied are Reynolds number, Peclet number, Damköhler number, and equilibrium reaction constant. These parameters encompass the influence of velocity, diffusivity, density, viscosity, hydraulic diameter, inlet concentration of species and absorption/desorption reaction constants. This work theoretically analyzes the influence of the above mentioned parameters using COMSOL Multiphysics 4.2.a. The governing equations of microfluidic devices, i.e. Navier-Stokes equations and the advection-diffusion equation, subjected to the above mentioned operating parameters, are solved to obtain the velocity profile, pressure drop and concentration profile of the species. The metric used for analyzing the influence of each operating parameter is the capture efficiency, i.e. the ratio of outlet concentration to inlet concentration as well the pressure drop. The results of this study would improve the design of microfluidic devices used for chemical reactions as well as that used for protein enrichment.

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Interfacial area and gas-side mass transfer coefficient of a gas—liquid absorption column: pilot-scale comparison of various tray types

Chemical Engineering and Processing - Process Intensification ◽

10.1016/0255-2701(90)87004-3 ◽

1990 ◽

Vol 27 (3) ◽

pp. 155-163 ◽

Cited By ~ 7

Author(s):

J.L Peytavy ◽

M.H Huor ◽

R Bugarel ◽

A Laurent

Keyword(s):

Mass Transfer ◽

Transfer Coefficient ◽

Mass Transfer Coefficient ◽

Interfacial Area ◽

Pilot Scale ◽

Absorption Column ◽

Liquid Absorption

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Effects of geometric parameters on volumetric mass transfer coefficient of non-Newtonian fluids in stirred tanks

International Journal of Chemical Reactor Engineering ◽

10.1515/ijcre-2021-0210 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Haider Ali ◽

Sofia Zhu ◽

Jannike Solsvik

Keyword(s):

Mass Transfer ◽

Transfer Coefficient ◽

Mass Transfer Coefficient ◽

Gas Flow ◽

Scale Up ◽

Pilot Scale ◽

Operating Conditions ◽

Volumetric Mass Transfer Coefficient ◽

Transfer Coefficients ◽

Stirred Tanks

Abstract Scaling up stirred tanks is a significant challenge because of the research gaps between laboratory and industrial-scale setups. It is necessary to understand the effects of scale-up on the mass transfer in stirred tanks, and this requires meticulous experimental analysis. The present study investigates the effects of tank size and aspect ratio ( H L T ${H}_{L}}{T}$ ) on the volumetric mass transfer coefficients of shear-thinning fluids. The experiments were conducted in three stirred tanks of different sizes (laboratory and pilot scale) and geometries (standard and nonstandard). H L T ${H}_{L}}{T}$ was 1 for the standard tanks and 3.5 for the nonstandard stirred tanks. Three sizes of stirred tanks were used: 11 L with H L T ${H}_{L}}{T}$ of 1, 40 L with H L T ${H}_{L}}{T}$ of 3.5, and 47 L with H L T ${H}_{L}}{T}$ of 1. Impeller stirring speeds and gas flow rates were in the range of 800–900 rev min−1 and 8–10 L min−1, respectively. The volumetric mass transfer coefficient was estimated based on the dissolved oxygen concentration in the fluids, and the effects of rheology and operating conditions on the volumetric mass transfer coefficient were observed. The volumetric mass transfer coefficient decreased as tank size increased and increased with an increase in operating conditions, but these effects were also clearly influenced by fluid rheology. The impacts of scale-up and operating conditions on the volumetric mass transfer coefficient decreased as liquid viscosity increased.

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