A Theoretical Fluid Dynamic Model for Estimation of the Hold-up and Liquid Velocity in an External Loop Airlift Bioreactor

This article demonstrates a new simplified mathematical model developed for an external loop airlift bioreactor, derived from recognised chemical engineering formulae, with the minimum possible reliance on empirical correlations with adjustable parameters. Bubble slip velocity, liquid circulation velocity and gas hold-up are simply estimated based on bubble diameter, gas flow rate, riser diameter and riser height. The model reveals the contribution of bubble diameter to gas hold-up and liquid circulation velocity, filling a gap in the literature. Bubble size is known as an important variable for optimising gas absorption and energy input. Validation of the model is conducted using our own and other experimental data. The current model was found to provide a better estimate of gas hold-up than the literature model compared with, but liquid velocity was overestimated. The impact of using various drag coefficient correlations was also revealed.

[1]  A. Margaritis,et al.  Hydrodynamic and Mass Transfer Characteristics of Three-Phase Gaslift Bioreactor Systems , 2001, Critical reviews in biotechnology.

[2]  Richard E. Kuhn,et al.  Application of Computational Fluid Dynamics , 2007 .

[3]  Don W. Green,et al.  Perry's Chemical Engineers' Handbook , 2007 .

[4]  Václav Tesař,et al.  Design of an airlift loop bioreactor and pilot scales studies with fluidic oscillator induced microbubbles for growth of a microalgae Dunaliella salina , 2011 .

[5]  N. Zuber,et al.  Drag coefficient and relative velocity in bubbly, droplet or particulate flows , 1979 .

[6]  R. Carbonell,et al.  Coupling of hydrodynamics and chemical reaction in gas-lift reactors , 1999 .

[7]  Y. Chisti,et al.  Airlift-driven external-loop tubular photobioreactors for outdoor production of microalgae: assessment of design and performance , 2001 .

[8]  Jose C. Merchuk,et al.  Airlift Bioreactors: Review of Recent Advances , 2008 .

[9]  Yong Jin,et al.  Effect of internal on the hydrodynamics in external-loop airlift reactors , 2005 .

[10]  Chapter 3 Physics of cavitation : GAS CONTENT AND NUCLEI , 2010 .

[11]  M. Mcpherson,et al.  Introduction to fluid mechanics , 1997 .

[12]  Karin Ackermann,et al.  Unit Operations Of Chemical Engineering , 2016 .

[13]  D. Das,et al.  Development of suitable photobioreactors for CO2 sequestration addressing global warming using green algae and cyanobacteria. , 2011, Bioresource technology.

[14]  F. G. Acién,et al.  Tubular photobioreactor design for algal cultures. , 2001, Journal of biotechnology.

[15]  Jacques Bouillard,et al.  Development of a complete model for an air-lift reactor , 2001 .

[16]  A. D. Young,et al.  An Introduction to Fluid Mechanics , 1968 .

[17]  L. Nikolov,et al.  Free rising spheres do not obey newton's law for free settling , 1992 .

[18]  Il-Hwan Seo,et al.  Review: Application of computational fluid dynamics for modeling and designing photobioreactors for microalgae production: A review , 2011 .

[19]  Yatish T. Shah,et al.  Design parameters estimations for bubble column reactors , 1982 .

[20]  Yusuf Chisti,et al.  Bioreactor applications in waste treatment , 1994 .

[21]  Marco A. Márquez,et al.  Hydrodynamic model for gas‐lift reactors , 1998 .

[22]  Francine Battaglia,et al.  Numerical Simulations for Hydrodynamics of Air-Water External Loop Airlift Reactor Flows With Bubble Break-Up and Coalescence Effects , 2013 .

[23]  J. Klein,et al.  A fluid dynamic model for three-phase airlift reactors , 1999 .

[24]  Jose C. Merchuk,et al.  Air-lift reactors in chemical and biological technology , 2007 .

[25]  R. Clift,et al.  Bubbles, Drops, and Particles , 1978 .

[26]  David F. Ollis,et al.  Airlift bioreactors: Analysis of local two‐phase hydrodynamics , 1991 .