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AL-Mashhadani, Mahmood K.H.; Wilkinson, Stephen J.; Zimmerman, William B. (2015)
Publisher: Elsevier BV
Journal: Chemical Engineering Science
Languages: English
Types: Article
Subjects: Applied Mathematics, Chemistry(all), Chemical Engineering(all), Industrial and Manufacturing Engineering
Airlift bioreactors can provide an attractive alternative to stirred tanks, particularly for bioprocesses with gaseous reactants or products. Frequently, however, they are susceptible to being limited by gas–liquid mass transfer and by poor mixing of the liquid phase, particularly when they are operating at high cell densities. In this work we use CFD modelling to show that microbubbles generated by fluidic oscillation can provide an effective, low energy means of achieving high interfacial area for mass transfer and improved liquid circulation for mixing.\ud \ud The results show that when the diameter of the microbubbles exceeded 200 µm, the “downcomer” region, which is equivalent to about 60% of overall volume of the reactor, is free from gas bubbles. The results also demonstrate that the use of microbubbles not only increases surface area to volume ratio, but also increases mixing efficiency through increasing the liquid velocity circulation around the draft tube. In addition, the depth of downward penetration of the microbubbles into the downcomer increases with decreasing bubbles size due to a greater downward drag force compared to the buoyancy force. The simulated results indicate that the volume of dead zone increases as the height of diffuser location is increased. We therefore hypothesise that poor gas bubble distribution due to the improper location of the diffuser may have a markedly deleterious effect on the performance of the bioreactor used in this work.
  • The results below are discovered through our pilot algorithms. Let us know how we are doing!

    • AL-Mashhadani, M.K.H, Bandalusena, H.C.H., Zimmerman, W.B., 2012. CO2 mass transfer induced through an airlift loop by a microbubble cloud generated by fluidic oscillation. Ind. Eng. Chem. Res. 51 (4), 1864-1877.
    • Becker, S., Sokolichin, A., Eigenberger, G., 1994. Gas-liquid flow in bubble columns and loop reactors: Part II. Comparison of detailed experiments and flow simulations. Chem. Eng. Sci. 49, 5747-5762.
    • Bello-Mendoza, R., Sharratt, P.N., 1998. Modelling the effects of imperfect mixing on the performance of anaerobic reactors for sewage sludge treatment. J. Chem. Technol. Biotechnol. 71, 121-130.
    • Calvo, E.G., Letón, P., 1991. A fluid dynamic model for bubble columns and airlift reactors. Chem. Eng. Sci. 46, 2947-2951.
    • Calvo, E.G., 1989. A fluid dynamic model for airlift loop reactors. Chem. Eng. Sci. 44, 321-323.
    • Calvo, E.G., Letón, P., Arranz, M.A., 1991. Prediction of gas hold up and liquid velocity in airlift loop reactors containing highly viscous Newtonian liquids. Chem. Eng. Sci. 46, 2951-2954.
    • Chisti, M.Y., 1989. Airlift Bioreactor. Elsevier Applied Science, London, UK.
    • Huang, Q., Yang, C., YU, G., Mao, Z.-S., 2010. CFD simulation of hydrodynamics and mass transfer in an internal airlift loop reactor using a steady two-fluid model. Chem. Eng. Sci. 65, 5527-5536.
    • Karim, K., Haffmann, R., Klasson, K.T., Al-Dahhan, M.H., 2005. Anaerobic digestion of animal waste: effect of mode of mixing. Water Res. 30 (15), 3597-3606.
    • Karim, K., Klasson, K.T., Hoffmann, R., Dresher, S.R., Depaoi, D.W., Al-Dahhan, H., 2003. Anaerobic digestion of animal waste: effect of mixing. Energ. Environ-UK 7 (359), 175-185.
    • Lay, J.-J., 2000. Modeling and optimization of anaerobic digested sludge converting starch to hydrogen. Biotechnol. Bioeng. 68, 269-278.
    • Lay, J.-J., 2001. Biohydrogen generation by mesophilic anaerobic fermentation of microcrystalline cellulose. Biotechnol. Bioeng. 74, 280-287.
    • Lewis, D.A., Davidson, J.F., 1985. Mass transfer in a recirculating bubble column. Chem. Eng. Sci. 40 (11), 2013-2017.
    • Maceiras, R., Álvarez, E., Cancela, M.A., 2010. Experimental interfacial area measurements in a bubble column. Chem. Eng. J. 163, 331-336.
    • Meroney, R.N., Colorado, P.E., 2009. CFD simulation of mechanical draft tube mixing in anaerobic digester tanks. Water Res. 43 (4), 1040-1050.
    • Metcalf, Eddy, 2003. Wastewater Engineering Treatment And Reuse. McGraw Hill, New York, USA.
    • Monteith, H.D., Stephenson, J.P., 1981. Mixing efficiencies in full-scale anaerobic digesters by tracer methods. Water Pollut. Control Fed. 53 (1), 78-84.
    • Moraveji, M.K., Sajjadi, B., Jafarkhani, M., Davarnejad, R., 2011. Experimental investigation and CFD simulation of turbulence effect on hydrodynamic and mass transfer in a packed bed airlift internal loop reactor. Int. Commun. Heat Mass 38, 518-524.
    • Mudde, R.F., Van Den Akker, H.E.A., 2001. 2D and 3D simulations of an internal airlift loop reactor on the basis of a two-fluid model. Chem. Eng. Sci. 56, 6351-6358.
    • Oey, R.S., Mudde, R.F., Portela, L.M., Van Den Akker, H.E.A., 2001. Simulation of a slurry airlift using a two-fluid model. Chem. Eng. Sci. 56, 673-681.
    • Prud'homme, R.K., Khan, S.A., 1996. Foams, theory, measurements, and applications. Surfactant Sci. Ser. 57, 146-151.
    • Rengel, A., Zoughaib, A., Dron, D., Clodic, D., 2012. Hydrodynamic study of an internal airlift reactor for microalgae culture. Appl. Microbiol. Biotechnol. 93, 117-129.
    • Seetharaman, S., McLean, A., Guthrie, R., Sridhar, S., 2014. Treatise on process Metallurgy, Process Phenomena, 2. Elsevier, Oxford, UK p. 199.
    • Šimčík, M., Mota, A., Ruzicka, M.C., Vicente, A., Teixeira, J., 2011. CFD simulation and experimental measurement of gas holdup and liquid interstitial velocity in internal loop airlift reactor. Chem. Eng. Sci. 66, 3268-3279.
    • Stafford, D.A., 2001. The effect of mixing and volatile fatty acid concentrations on anaerobic digestion performance. Biomass 2, 43-55.
    • Stevenson, P., Li, X., 2014. Foam Fractionation, Principles and Process Design. Talyor and Francis group, CRC press p. 113.
    • Stroot, P.G., Mcmahon, K.D., Mackie, R.I., Raskin, L., 2001. Anerobic codigestion of municipal solid waste and biosoilds under various mixing conditions- I. Digester performance. Water. Res. 35 (7), 1804-1816.
    • Terashima, M., Goel, R., Komatsu, K., Yasui, H., Takahashi, H., Li, Y.Y., Noike, T., 2009. CFD simulation of mixing in anaerobic digesters. Bioresour. Technol. 100 (7), 2228-2233.
    • Vesvikar, M.S., Al-Dahhan, M., 2005. Flow pattern visualization in a mimic anaerobic digester using CFD. Biotechnol. Bioeng. 89 (6), 719-732.
    • Wu, B., 2009. CFD analysis of mechanical mixing in anaerobic digesters. Trans. ASABE 52 (4), 1371-1382.
    • Wu, B., 2010. CFD simulation of mixing in egg-shaped anaerobic digesters. Water Res. 44 (5), 1507-1519.
    • Wu, B., Chen, S., 2008. CFD simulation of non-Newtonian fluid flow in anaerobic digester”. Biotchnol. Bioegin 99 (3), 700-711.
    • Yawalkar, A.A., Vishwas, G., Pangarkar, V.G., Anthony Beenackers, A.A.C.M., 2002. Gas Hold-Up in Stirred Tank Reactors. Can. J. Chem. Eng. 80, 158-166.
    • Ying, K., Zimmerman, W.B., Gilmour, D.J., 2014. Effects of CO and pH on growth of the microalga Dunaliella salina. J. Microb. Biochem. Technol. 6 (3), 167-173.
    • Ying, K., Gilmour, D.J., Shi, Y., Zimmerman, W.B., 2013a. Growth enhancement of Dunaliella salina by microbubble induced airlift loop bioreactor (ALB)-the relation between mass transfer and growth rate. J. Biomater. Nanobiotechnol. 4 (2A), 1-9.
    • Ying, K., Al-Mashhadani, M.K.H, Hanotu, James O., Gilmour, D.J., Zimmerman, W.B., 2013b. Enhanced mass transfer in microbubble driven airlift bioreactor for microalgal culture. J. Eng. 5 (9), 735-743.
    • Zayas, J.F., 1997. Functionality of Proteins in Food. Springer-Verlag, Berlin Heidelberg p. 274.
    • Zimmerman, W.B., Zandi, M., Bandulasena, H.C.H., Tesar,̌ V., Gilmour, D.J., Ying, K., 2011a. Design of an airlift loop bioreactor and pilot scales studies with fluidic oscillator induced microbubbles for growth of a microalgae Dunaliella salina. Appl. Energy 88, 3357-3369.
    • Zimmerman, W.B., Hewakandamby, B.N., Tesar, V., Bandulasena, H.C.H., Omotowa, O.A., 2009. On the design and simulation of an airlift loop bioreactor with microbubble generation by fluidic oscillation. Food Bioprod. Process 87, 215-227.
    • Zimmerman, W.B., Václav Tesař, H.C., Bandulasena, Hemaka, 2011b. Towards energy efficient nanobubble generation with fluidic oscillation. Curr. Opin. Colloid Interface Sci. 16 (4), 350-356.
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