Stirred tanks; Hydrodynamics; Mixing; Mass transfer; PIV; PLIF
Abstract :
[en] In stirred-tank bioreactors, flow structures of various length and time scales are implied in scalar transport phenomena, such as gas species transfer through the liquid free-surface and their homogenization in the bulk. A proper understanding of the underlying mechanisms, i.e. hydrodynamics, mixing and mass transfer, and of their interactions is required to design and develop reliable and efficient production-scale bioprocesses. The objective of the present work is to experimentally investigate the coupling between gas-liquid mass transfer of oxygen with mixing efficiency and circulation patterns inside an arbitrarily chosen stirred-tank configuration aerated through the liquid free-surface, a baffled 20 L-vessel agitated by two Rushton turbines. Based on global parameter values, the most appropriate rotating speed, N = 300 rpm, is selected in order to further study local hydrodynamic quantities using Particle Image Velocimetry (PIV), as well as mixing and mass transfer dynamics using Planar Laser-Induced Fluorescence (PLIF). The results obtained with these local experimental methods are analyzed in detail. Their averages are first successfully compared to global data. Statistical analysis of their spatial distributions show that large-scale flow patterns significantly influence mass transfer through the free-surface of the stirred tank. Even if global measurements show that global characteristic times for mixing and mass transfer differ by two orders of magnitude, local experimental characterization shows persistent vertical gradients of dissolved gas concentrations. So the dissolved gas concentration is not as perfectly uniform as one might expect.
Disciplines :
Chemical engineering
Author, co-author :
de Lamotte, Anne ; Université de Liège > Department of Chemical Engineering > Génie de la réaction et des réacteurs chimiques
Delafosse, Angélique ; Université de Liège > Department of Chemical Engineering > Génie de la réaction et des réacteurs chimiques
Calvo, Sébastien ; Université de Liège > Department of Chemical Engineering > Génie de la réaction et des réacteurs chimiques
Delvigne, Frank ; Université de Liège > Agronomie, Bio-ingénierie et Chimie (AgroBioChem) > Microbial, food and biobased technologies
Toye, Dominique ; Université de Liège > Department of Chemical Engineering > Génie de la réaction et des réacteurs chimiques
Language :
English
Title :
Investigating the effects of hydrodynamics and mixing on mass transfer through the free-surface in stirred tank bioreactors
Publication date :
23 November 2017
Journal title :
Chemical Engineering Science
ISSN :
0009-2509
eISSN :
1873-4405
Publisher :
Pergamon Press - An Imprint of Elsevier Science, Oxford, United Kingdom
Albani, J.R., Principles and Applications of Fluorescence Spectroscopy. 2008, John Wiley & Sons.
Alberini, F., Simmons, M.J.H., Ingram, A., Stitt, E.H., Use of an areal distribution of mixing intensity to describe blending of non-newtonian fluids in a kenics KM static mixer using PLIF. AIChE J. 60:1 (2014), 332–342.
Bałdyga, J., Pohorecki, R., Turbulent micromixing in chemical reactors – a review. Chem. Eng. J. Biochem. Eng. J. 58:2 (1995), 183–195.
Banerjee, S., Lakehal, D., Fulgosi, M., Surface divergence models for scalar exchange between turbulent streams. Int. J. Multiph. Flow 30:7–8 (2004), 963–977.
Bouwmans, I., Bakker, A., Van den Akker, H., Fluid flow blending liquids of differing viscosities and densities in stirred vessels. Chem. Eng. Res. Des. 75:8 (1997), 777–783.
Bugay, S., 1998. Analyse locale des échelles caractéristiques du mélange: Application de la technique P.I.V. aux cuves agitées (Ph.D. thesis). Institut National des Sciences Appliquées, Toulouse, France.
Burmester, S.S.H., Rielly, C.D., Edwards, M.F., The Mixing of Miscible Liquids with Large Differences in Density and Viscosity. 1992, Springer, Netherlands, Dordrecht, 83–90.
Busciglio, A., Grisafi, F., Scargiali, F., Brucato, A., Mixing dynamics in uncovered unbaffled stirred tanks. Chem. Eng. J. 254 (2014), 210–219.
Busciglio, A., Montante, G., Paglianti, A., Flow field and homogenization time assessment in continuously-fed stirred tanks. Chem. Eng. Res. Des. 102 (2015), 42–56.
Cents, A., de Bruijn, F., Brilman, D., Versteeg, G., Validation of the danckwerts-plot technique by simultaneous chemical absorption of CO2 and physical desorption of O2. Chem. Eng. Sci. 60:21 (2005), 5809–5818.
Chu, C.R., Jirka, G.H., Turbulent gas flux measurements below the air-water interface of a grid-stirred tank. Int. J. Heat Mass Transfer 35:8 (1992), 1957–1968.
Chung, K., Barigou, M., Simmons, M., Reconstruction of 3-D flow field inside miniature stirred vessels using a 2-D PIV technique. Chem. Eng. Res. Des. 85:5 (2007), 560–567.
Coroneo, M., Montante, G., Paglianti, A., Magelli, F., CFD prediction of fluid flow and mixing in stirred tanks: Numerical issues about the RANS simulations. Comput. Chem. Eng. 35:10 (2011), 1959–1968.
Danckwerts, P.V., Significance of liquid-film coefficients in gas absorption. Ind. Eng. Chem. 43:6 (1951), 1460–1467.
Danckwerts, P.V., The definition and measurement of some characteristics of mixtures. Appl. Sci. Res. Sect. A 3:4 (1952), 279–296.
Delafosse, A., Collignon, M.-L., Calvo, S., Delvigne, F., Crine, M., Thonart, P., Toye, D., CFD-based compartment model for description of mixing in bioreactors. Chem. Eng. Sci. 106 (2014), 76–85.
Delvigne, F., Lejeune, A., Destain, J., Thonart, P., Modelling of the substrate heterogeneities experienced by a limited microbial population in scale-down and in large-scale bioreactors. Chem. Eng. J. 120:3 (2006), 157–167.
Derksen, J., Doelman, M., Van den Akker, H., Three-dimensional LDA measurements in the impeller region of a turbulently stirred tank. Exp. Fluids 27:6 (1999), 522–532.
Enfors, S.-O., Jahic, M., Rozkov, A., Xu, B., Hecker, M., Jügen, B., Krüger, E., Schweder, T., Hamer, G., O'Beirne, D., Noisommit-Rizzi, N., Reuss, M., Boone, L., Hewitt, C., McFarlane, C., Nienow, A., Kovacs, T., Trägårdh, C., Fuchs, L., Revstedt, J., Friberg, P., Hjertager, B., Blomsten, G., Skogman, H., Hjort, S., Hoeks, F., Lin, H.-Y., Neubauer, P., van der Lans, R., Luyben, K., Vrabel, P., Manelius, A., Physiological responses to mixing in large scale bioreactors. J. Biotechnol. 85:2 (2001), 175–185.
Escudié, R., Liné, A., Experimental analysis of hydrodynamics in a radially agitated tank. AIChE J. 49:3 (2003), 585–603.
Escudié, R., Liné, A., Analysis of turbulence anisotropy in a mixing tank. Chem. Eng. Sci. 61:9 (2006), 2771–2779.
Falkenroth, A., Degreif, K., Jähne, B., Visualisation of Oxygen Concentration Fields in the Mass Boundary Layer by Fluorescence Quenching. 2007, Springer, Berlin, Heidelberg, 59–72.
Fall, A., Lecoq, O., David, R., Characterization of mixing in a stirred tank by planar laser induced fluorescence (P.L.I.F.). Chem. Eng. Res. Des. 79:8 (2001), 876–882.
Fortescue, G., Pearson, J., On gas absorption into a turbulent liquid. Chem. Eng. Sci. 22:9 (1967), 1163–1176.
Gabriele, A., Nienow, A., Simmons, M., Use of angle resolved PIV to estimate local specific energy dissipation rates for up- and down-pumping pitched blade agitators in a stirred tank. Chem. Eng. Sci. 64:1 (2009), 126–143.
Galletti, C., Brunazzi, E., Pintus, S., Paglianti, A., Yianneskis, M., Triple products and turbulence states in a radially stirred tank with 3-D laser anemometry. Chem. Eng. Res. Des. 82:9 (2004), 1214–1228.
Garcia-Ochoa, F., Gomez, E., Bioreactor scale-up and oxygen transfer rate in microbial processes: an overview. Biotechnol. Adv. 27:2 (2009), 153–176.
Godoy-Silva, R., Berdugo, C., Chalmers, J.J., Flickinger, M.C., Aeration, Mixing, and Hydrodynamics, Animal Cell Bioreactors. 2009, John Wiley & Sons, Inc.
Gogate, P.R., Pandit, A.B., Mixing of miscible liquids with density differences: effect of volume and density of the tracer fluid. Can. J. Chem. Eng. 77:5 (1999), 988–996.
Guillard, F., Trägårdh, C., Fuchs, L., A study on the instability of coherent mixing structures in a continuously stirred tank. Chem. Eng. Sci. 55:23 (2000), 5657–5670.
Hamborg, E.S., Kersten, S.R., Versteeg, G.F., Absorption and desorption mass transfer rates in non-reactive systems. Chem. Eng. J. 161:1–2 (2010), 191–195.
Hartmann, H., Derksen, J.J., Van den Akker, H.E.A., Mixing times in a turbulent stirred tank by means of LES. AIChE J. 52:11 (2006), 3696–3706.
Herlina, Jirka, G.H., Application of LIF to investigate gas transfer near the air-water interface in a grid-stirred tank. Exp. Fluids 37:3 (2004), 341–349.
Herlina, H., Wissink, J.G., Direct numerical simulation of turbulent scalar transport across a flat surface. J. Fluid Mech. 744 (2014), 217–249.
Hinze, J., Turbulence: An Introduction to its Mechanism and Theory McGraw-Hill series in Mechanical Engineering, 1959, McGraw-Hill.
Houcine, I., Vivier, H., Plasari, E., David, R., Villermaux, J., Planar laser-induced fluorescence technique for measurements of concentration fields in continuous stirred tank reactors. Exp. Fluids 22:2 (1996), 95–102.
Jakobsen, H.A., Single Phase Flow. 2008, Springer, Berlin, Heidelberg, 3–185.
Janzen, J.G., Herlina, H., Jirka, G.H., Schulz, H.E., Gulliver, J.S., Estimation of mass transfer velocity based on measured turbulence parameters. AIChE J. 56:8 (2010), 2005–2017.
Jimenez, M., Dietrich, N., Cockx, A., Hébrard, G., Experimental study of O2 diffusion coefficient measurement at a planar gas-liquid interface by planar laser-induced fluorescence with inhibition. AIChE J. 59:1 (2013), 325–333.
Jimenez, M., Dietrich, N., Grace, J.R., Hébrard, G., Oxygen mass transfer and hydrodynamic behaviour in wastewater: Determination of local impact of surfactants by visualization techniques. Water Res. 58 (2014), 111–121.
Kasat, G.R., Pandit, A.B., Mixing time studies in multiple impeller agitated reactors. Can. J. Chem. Eng. 82:5 (2004), 892–904.
Khan, F., Rielly, C., Hargrave, G., A multi-block approach to obtain angle-resolved PIV measurements of the mean flow and turbulence fields in a stirred vessel. Chem. Eng. Technol. 27:3 (2004), 264–269.
Kukukova, A., Aubin, J., Kresta, S.M., A new definition of mixing and segregation: three dimensions of a key process variable. Chem. Eng. Res. Des. 87:4 (2009), 633–647 13th European Conference on Mixing: New developments towards more efficient and sustainable operations.
Kukukova, A., Aubin, J., Kresta, S.M., Measuring the scale of segregation in mixing data. Can. J. Chem. Eng. 89:5 (2011), 1122–1138.
Kukuková, A., Noël, B., Kresta, S.M., Aubin, J., Impact of sampling method and scale on the measurement of mixing and the coefficient of variance. AIChE J. 54:12 (2008), 3068–3083.
Lakowicz, J.R., Principles of Fluorescence Spectroscopy. 2013, Springer Science & Business Media.
Lamont, J.C., Scott, D.S., An eddy cell model of mass transfer into the surface of a turbulent liquid. AIChE J. 16:4 (1970), 513–519.
Larsson, G., Törnkvist, M., Wernersson, E.S., Trägårdh, C., Noorman, H., Enfors, S.O., Substrate gradients in bioreactors: origin and consequences. Bioprocess. Eng. 14:6 (1996), 281–289.
Liné, A., Eigenvalue spectrum versus energy density spectrum in a mixing tank. Chem. Eng. Res. Des. 108 (2016), 13–22.
Liné, A., Gabelle, J.-C., Morchain, J., Anne-Archard, D., Augier, F., On POD analysis of PIV measurements applied to mixing in a stirred vessel with a shear thinning fluid. Chem. Eng. Res. Des. 91:11 (2013), 2073–2083.
Linek, V., Vacek, V., Beneš, P., A critical review and experimental verification of the correct use of the dynamic method for the determination of oxygen transfer in aerated agitated vessels to water, electrolyte solutions and viscous liquids. Chem. Eng. J. 34:1 (1987), 11–34.
Martín, M., Montes, F.J., Galán, M.A., On the contribution of the scales of mixing to the oxygen transfer in stirred tanks. Chem. Eng. J. 145:2 (2008), 232–241.
Mathpati, C.S., Tabib, M.V., Deshpande, S.S., Joshi, J.B., Dynamics of flow structures and transport phenomena, 2. Relationship with design objectives and design optimization. Ind. Eng. Chem. Res. 48:17 (2009), 8285–8311.
McCready, M.J., Vassiliadou, E., Hanratty, T.J., Computer simulation of turbulent mass transfer at a mobile interface. AIChE J. 32:7 (1986), 1108–1115.
Micheletti, M., Baldi, S., Yeoh, S., Ducci, A., Papadakis, G., Lee, K., Yianneskis, M., On spatial and temporal variations and estimates of energy dissipation in stirred reactors. Chem. Eng. Res. Des. 82:9 (2004), 1188–1198.
Montante, G., Coroneo, M., Paglianti, A., Blending of miscible liquids with different densities and viscosities in static mixers. Chem. Eng. Sci. 141 (2016), 250–260.
Morchain, J., Gabelle, J., Cockx, A., A coupled population balance model and CFD approach for the simulation of mixing issues in lab-scale and industrial bioreactors. AIChE J. 60:1 (2014), 27–40.
Nienow, A., On impeller circulation and mixing effectiveness in the turbulent flow regime. Chem. Eng. Sci. 52:15 (1997), 2557–2565.
Rielly, C., Smith, D., Lindley, J., Niranjan, K., Phillips, V., Mixing processes for agricultural and food materials: Part 4, assessment and monitoring of mixing systems. J. Agric. Eng. Res. 59:1 (1994), 1–18.
Scargiali, F., Busciglio, A., Grisafi, F., Brucato, A., Simplified dynamic pressure method for measurement in aerated bioreactors. Biochem. Eng. J. 49:2 (2010), 165–172.
Taylor, G.I., Statistical theory of turbulence. Proc. Roy. Soc. London A: Math. Phys. Eng. Sci. 151:873 (1935), 421–444.
Tsumori, H., Sugihara, Y., Lengthscales of motions that control air–water gas transfer in grid-stirred turbulence. J. Mar. Syst. 66:1–4 (2007), 6–18.
Van't Riet, K., Review of measuring methods and results in nonviscous gas-liquid mass transfer in stirred vessels. Ind. Eng. Chem. Process Des. Dev. 18:3 (1979), 357–364.
Variano, E.A., Cowen, E.A., Turbulent transport of a high-schmidt-number scalar near an air-water interface. J. Fluid Mech. 731 (2013), 259–287.
