Two-Phase CFD Simulation Coupled with Chemical Reactions in a Plug-Flow Reactor

Document Type : Research Article

Authors

1 Department of Biosystem Engineering, Faculty of Agricultural Engineering, Bu-Ali Sina University, Hamedan, I.R. IRAN

2 Biotechnology Group, Chemical Engineering Department, Tarbiat Modares University, Tehran, I.R. IRAN

3 Department of Biosystem Engineering, Faculty of Agricultural Engineering, Tabriz University, Tabriz, I.R. IRAN

Abstract

In order to design and exploit a process successfully, it's necessary to understand how it works. Anaerobic digestion is a sequential complex biochemical process that involves a series of reactions that are mediated by several different groups of anaerobic microorganisms. This research describes a simulation-based on three-dimensional Computational Fluid Dynamics (CFD) coupled with reactions in a semi-continuous Plug Flow Reactor (PFR). The commercial software FLUENT 6.3 was employed to solve the governing equations. The gas-liquid flow was modeled using a Eulerian multiphase and k-e turbulence (RNG) model. Hydrodynamics and anaerobic digestion reactions investigated the mixing regime using the Multiple Reference Frame (MRF) model within the whole multiphase bioreactor. Simulation results indicate that flow pattern within the reactor was highly influenced by the substrate density and viscosity, and stirring intensity. A comparison of three impellers mixing speed in the reactor demonstrates that mixing intensity has affected the gas phase above the fluid surface. Such a mixing intensity may create a turbulent region with a homogenous mixture of gas and liquid, which is not suitable for this anaerobic digestion. Concentration profiles of CH4 and CO2 in the anaerobic system displayed a plug flow pattern.

Keywords

Main Subjects


[1] Khanal S.K., "Anaerobic Biotechnology for Bioenergy Production: Principles and Applications": John Wiley & Sons, Inc., USA, (2008).
[2] Deublein D. and Steinhauser A., "Biogas from Waste and Renewable Resources: An Introduction", 1st ed.: Wiley-VCH, (2008).
[3] Cao Y. and Pawłowski A., Sewage Sludge-to-Energy Approaches Based on Anaerobic Digestion and Pyrolysis: Brief Overview and Energy Efficiency Assessment, Renewable and Sustainable Energy Reviews, 16: 1657-1665 (2012).
[4] Cheng J., "Biomass to Renewable Energy Processes", 1st ed.: CRC Press Inc., (2010).
[5] Appels L., Baeyens J., Degrève J., Dewil R., Principles and Potential of the Anaerobic Digestion of Waste-Activated Sludge, Prog. Energy Combust. Sci., 34: 755-781 (2008).
[6] Bouallagui H., Touhami Y., Ben Cheikh R., Hamdi M., Bioreactor Performance in Anaerobic Digestion of Fruit and Vegetable Wastes, Process Biochem, 40: 989-995 (2005).
[7] Batten J. J., Design of a Plug Flow Reactor, Combust. Sci. Technol., 1: 365-367 (1970).
[8] Chen C. R., The State of the Art Review on the Application of Anaerobic Digestion, Conservation and Recycling, 7: 191-198 (1984).
[9] Rintala J. A. Ahring B. K., Thermophilic Anaerobic Digestion of Source-Sorted Household Solid Waste: The Effects of Enzyme Additions, Appl. Microbiol. Biotechnol., 40: 916-919 (1994).
[10] Gunaseelan V. N., Anaerobic Digestion of Biomass for Methane Production: A Review, Biomass Bioenergy, 13: 83-114 (1997).
[11] Husain A., Mathematical Models of the Kinetics of Anaerobic Digestion - A Selected Review, Biomass Bioenergy, 14: 561-571 (1998).
[12] Weedermann M., Seo G., Wolkowicz G. S. K., Mathematical Model of Anaerobic Digestion
in a Chemostat: Effects of Syntrophy and Inhibition
, J. Biol. Dyn., 7: 59-85 // (2013).
[13] Andrews J. F., Dynamic Model of Anaerobic Digestion Process, Purdue Univ-Eng Extension Ser, 132: 285-310 (1969).
[14] Salminen E. Rintala J., Anaerobic Digestion of Organic Solid Poultry Slaughterhouse Waste - A Review, Bioresour Technol., 83: 13-26 (2002).
[15] Zakarya I. A., Abustan I., Ismail N., Yusoff M.S., Production of Methane Gas from Organic Fraction Municipal Solid Waste (OFMSW) via Anaerobic Process: Application Methodology for the Malaysian Condition, International Journal of Environment and Waste Management, 12: 121-129 (2013).
[16] Yadvika, Santosh, Sreekrishnan T.R., Kohli S., Rana V., Enhancement of Biogas Production from Solid Substrates Using Different Techniques-a Review, Bioresour. Technol., 95: 1-10 (2004).
[17] Demirel B., Yenigun O., Onay T. T., Anaerobic Treatment of Dairy Wastewaters: A Review, Process Biochem.: 40: 2583-2595 (2005).
[18] Aiyuk S., Forrez I., van Haandel A., Verstraete W., Anaerobic and Complementary Treatment of Domestic Sewage in Regions with Hot Climates-A Review, Bioresour Technol., 97: 2225-2241 (2006).
[19] Leitão R. C., Van Haandel A. C., Zeeman G., Lettinga G., The Effects of Operational
and Environmental Variations on Anaerobic Wastewater Treatment Systems: A Review
, Bioresour Technol., 97: 1105-1118 (2006).
[20] Keshtkar A., Meyssami B., Abolhamd G., Ghaforian H., Khalagi Asadi M., Mathematical Modeling of Non-Ideal Mixing Continuous Flow Reactors for Anaerobic Digestion of Cattle Manure, Bioresour Technol., 87: 113-124 (2003).
[21] Lindmark J., Thorin E., Bel Fdhila R., Dahlquist E., Effects of Mixing on the Result of Anaerobic Digestion: Review, Renewable and Sustainable Energy Reviews, 40: 1030-1047 (2014).
[22] Wu B., CFD Analysis of Mechanical Mixing in Anaerobic Digesters, Transactions of the ASABE, 52: 1371-1382 (2009).
[23] Kaparaju P., Buendia I., Ellegaard L., Angelidakia I., Effects of Mixing on Methane Production During Thermophilic Anaerobic Digestion of Manure: Lab-Scale and Pilot-Scale Studies, Bioresour Technol, 99: 4919-4928 (2008).
[24] Karim K., Hoffmann R., Thomas Klasson K., Al-Dahhan M. H., Anaerobic Digestion of Animal Waste: Effect of Mode of Mixing, Water Res., 39: 3597-3606 (2005).
[25] Chen Y., Cheng J. J., Creamer K.S., Inhibition of Anaerobic Digestion Process: A Review, Bioresour Technol., 99: 4044-4064 (2008).
[26] Lesteur M., Bellon-Maurel V., Gonzalez C., Latrille E., Roger J., Junqua G.,Steyer J.P., Alternative Methods for Determining Anaerobic Biodegradability: A Review, Process Biochem., 45: 431-440 (2010).
[27] Amani T., Nosrati M., Sreekrishnan T., Anaerobic Digestion from the Viewpoint of Microbiological, Chemical, and Operational Aspects-A Review, Environ Rev., 18: 255-278 (2010).
[28] Zhang Z., Li W., Zhang G., and Xu G., Impact of Pretreatment on Solid State Anaerobic Digestion of Yard Waste for Biogas Production, World. J. Microbiol. Biotechnol., 30: 547–554 (2014).
[29] Markowski M., Białobrzewski I., Zieliński M., Dębowski M., Krzemieniewski M., Optimizing Low-Temperature Biogas Production from Biomass by Anaerobic Digestion, Renewable Energy, 69: 219-225 (2014).
[30] Hurtado F. J., Kaiser A. S., Zamora B., Fluid Dynamic Analysis of a Continuous Stirred Tank Reactor for Technical Optimization of Wastewater Digestion, Water. Res.: 71: 282-293 (2015).
[31] Azargoshasb H., Mousavi S., Amani T., Jafari A., Nosrati M., Three-Phase CFD Simulation Coupled with Population Balance Equations of Anaerobic Syntrophic Acidogenesis and Methanogenesis Reactions in a Continuous Stirred Bioreactor, Journal of Industrial and Engineering Chemistry, 27: 207-217 (2015).
 [32] Wu B., Advances in the use of CFD to Characterize, Design and Optimize Bioenergy Systems, Comput Electron Agric, 93: 195-208 (2013).
[33] Craig K. J., Nieuwoudt M. N., Niemand L. J., CFD Simulation of Anaerobic Digester with Variable Sewage Sludge Rheology, Water Res., 47: 4485-4497 (2013).
[35] Shah F. A., Mahmood Q., Rashid N., Pervez A., Raja I. A., Shah M.M., Co-Digestion, Pretreatment and Digester Design for Enhanced Methanogenesis, Renewable and Sustainable Energy Reviews, 42: 627-642 (2015).
[36] Tiwary A., Williams I.D., Pant D.C., Kishore V.V.N., Emerging Perspectives on Environmental Burden Minimisation Initiatives from Anaerobic Digestion Technologies for Community Scale Biomass Valorisation, Renewable and Sustainable Energy Reviews, 42: 883-901 (2015).
[37] Yu L., Ma J., Chen S., Numerical Simulation of Mechanical Mixing in High Solid Anaerobic Digester, Bioresour Technol., 102: 1012-1018 (2011).
[38] Wu B., Large Eddy Simulation of Mechanical Mixing in Anaerobic Digesters, Biotechnol. Bioeng., 109: 804-812 (2012).
[39] Terashima M., Goel R., Komatsu K., Yasui H., Takahashi H., Li Y., et al., CFD Simulation of Mixing in Anaerobic Digesters, Bioresour Technol., 100: 2228-2233 (2009).
[40] Bridgeman J., Computational Fluid Dynamics Modelling of Sewage Sludge Mixing in an Anaerobic Digester, Adv. Eng. Software, 44: 54-62 (2012).
[41] Alexandra M.M., Modeling Flow Inside an Anaerobic Digester by CFD Techniques, Energy and Enviroment, 2: 963-974 (2011).
[42] Wu B., Bibeau E. L., Gebremedhin K.G., Three-Dimensional Numerical Simulation Model of Biogas Production for Anaerobic Digesters, Canadian Biosystems Engineering / Le Genie des biosystems au Canada, 51: 8.1-8.7 (2009).
[43] Wadhwani R. Mohanty B., Computational Fluid Dynamics Study of a Complete Coal Direct Chemical Looping Sub-Pilot Unit, Iran. J. Chem. Chem. Eng. (IJCCE), 35(3): 139-153 (2016).
[44] Rasouli M., Ajabshirchi Y., Mousavi S. M., Nosrati M., Yaghmaei S., Process Optimization and Modeling of Anaerobic Digestion of Cow Manure for Enhanced Biogas Yield in a Mixed Plug-Flow Reactor Using Response Surface Methodology, Biosci Biotech R Asia, 12: 2333-2344 (2015).
[45] Roache P. J., "Verification and Validation in cComputational Science and Engineering", Hermosa Publishers, Albuquerque, New Mexico., (1998).
[46] Committee V., “Standard for Verification and Validation in Computational Fluid Dynamics and Heat Transfer”, American Society of Mechanical Engineers, New York, (2009).
[47] Jahoda M., Tomášková L., Moštěk M., CFD Prediction of Liquid Homogenisation in a Gas–Liquid Stirred Tank, Chem. Eng. Res. Des., 87: 460-467 (2009).
[48] Ding J., Wang X., Zhou X.-F., Ren N.-Q., Guo W.-Q., CFD Optimization of Continuous Stirred-Tank (CSTR) Reactor for Biohydrogen Production, Bioresour Technol., 101: 7005-7013 (2010).
[49] Bhole M., Joshi J., Ramkrishna D., CFD Simulation of Bubble Columns Incorporating Population Balance Modeling, Chem. Eng. Sci., 63: 2267-2282 (2008).
[50] Versteeg H. K., Malalasekera W., "An Introduction to Computational Fluid Dynamics: The Finite Volume Method", 2nd ed.: Pearson Education, (2007).
[51] Patankar S., "Numerical Heat Transfer and Fluid Flow", McGraw Hill, New York, USA, (1980).
[52] Angelidaki I., Ellegaard L., Ahring B. K., A Mathematical Model for Dynamic Simulation of Anaerobic Digestion of Complex Substrates: Focusing on Ammonia Inhibition, Biotechnol. Bioeng., 42: 159-166 (1993).
[53] Gerardi M. H., "Wastewater Microbiology Series: The microbiology of Anaerobic Digesters", United States, America: John Wiley & Sons, Inc (2003).
[54] Fluent I., "FLUENT 6.3 User’s Guide," ed: Fluent, Inc. Lebanon, NH, Inc. Ed. (2006).
[56] Karim K., Varma R., Vesvikar M., Al-Dahhan M.H., Flow Pattern Visualization of a Simulated Digester, Water Res., 38: 3659-3670 (2004).