Effective lateral dispersion of momentum, heat and mass in bubbling fluidized beds

Abstract

The lateral dispersion of bed material in a bubbling fluidized bed is a key parameter in the prediction of the effective in-bed heat transfer and transport of heterogenous reactants, properties important for the successful design and scale-up of thermal and/or chemical processes. Computational fluid dynamics simulations offer means to investigate such beds in silico and derive effective parameters for reduced-order models. In this work, we use the Eulerian-Eulerian two-fluid model with the kinetic theory of granular flow to perform numerical simulations of solids mixing and heat transfer in bubbling fluidized beds. We extract the lateral solids dispersion coefficient using four different methods: by fitting the transient response of the bed to (1) an ideal heat or (2) mass transfer problem, (3) by extracting the time-averaged heat transfer behavior and (4) through a momentum transfer approach in an analogy with single-phase turbulence. The method (2) fitting against a mass transfer problem is found to produce robust results at a reasonable computational cost when assessed against experiments. Furthermore, the gas inlet boundary condition is shown to have a significant effect on the prediction, indicating a need to account for nozzle characteristics when simulating industrial cases.

Graphical abstract

Keywords

effective dispersion / heat transfer / mass transfer / mixing / gas-solid fluidized bed

References

[1] YangW C. Handbook of Fluidization and Fluid-Particle Systems. Taylor & Francis, 2003

[2] Kraussler M , Binder M , Schindler P , Hofbauer H . Hydrogen production within a polygeneration concept based on dual fluidized bed biomass steam gasification. Biomass and Bioenergy, 2018, 111: 320–329

[3] Heinze C , May J , Peters J , Ströhle J , Epple B . Techno-economic assessment of polygeneration based on fluidized bed gasification. Fuel, 2019, 250: 285–291

[4] Eschenbacher A , Jensen P A , Henriksen U B , Ahrenfeldt J , Jensen C D , Li C , Enemark-Rasmussen K , Duus J Ø , Mentzel U V , Jensen A D . Catalytic upgrading of tars generated in a 100 kWth low temperature circulating fluidized bed gasifier for production of liquid bio-fuels in a polygeneration scheme. Energy Conversion and Management, 2020, 207: 112538

[5] Salman C A , Naqvi M , Thorin E , Yan J . Impact of retrofitting existing combined heat and power plant with polygeneration of biomethane: a comparative techno-economic analysis of integrating different gasifiers. Energy Conversion and Management, 2017, 152: 250–265

[6] Salman C A , Omer C B . Process modelling and simulation of waste gasification-based flexible polygeneration facilities for power, heat and biofuels production. Energies, 2020, 13(16): 4264

[7] Gadsbøll R Ø , Clausen L R , Thomsen T P , Ahrenfeldt J , Henriksen U B . Flexible TwoStage biomass gasifier designs for polygeneration operation. Energy, 2019, 166: 939–950

[8] Yu P , Luo Z , Wang Q , Fang M . Life cycle assessment of transformation from a sub-critical power plant into a polygeneration plant. Energy Conversion and Management, 2019, 198: 111801

[9] Naqvi M , Dahlquist E , Yan J , Naqvi S R , Nizami A S , Salman C A , Danish M , Farooq U , Rehan M , Khan Z . . Polygeneration system integrated with small non-wood pulp mills for substitute natural gas production. Applied Energy, 2018, 224: 636–646

[10] Zhao K , Thunman H , Pallarès D , Ström H . Control of the solids retention time by multi-staging a fluidized bed reactor. Fuel Processing Technology, 2017, 167: 171–182

[11] Salehi M S , Askarishahi M , Radl S . Quantification of solid mixing in bubbling fluidized beds via two-fluid model simulations. Industrial & Engineering Chemistry Research, 2020, 59(22): 10606–10621

[12] Diba M F , Karim M R , Naser J . Numerical modelling of a bubbling fluidized bed combustion: a simplified approach. Fuel, 2020, 277: 118170

[13] Jiradilok V , Gidaspow D , Breault R W . Computation of gas and solid dispersion coefficients in turbulent risers and bubbling beds. Chemical Engineering Science, 2007, 62(13): 3397–3409

[14] Oke O , Lettieri P , Salatino P , Solimene R , Mazzei L . Numerical simulations of lateral solid mixing in gas-fluidized beds. Chemical Engineering Science, 2014, 120: 117–129

[15] Hernández-Jiménez H , Sánchez-Prieto J , Cano-Pleite E , Soria-Verdugo A . Lateral solids meso-mixing in pseudo-2D fluidized beds by means of TFM simulations. Powder Technology, 2018, 334: 183–191

[16] Yu M , Miller D C , Biegler L T . Dynamic reduced order models for simulating bubbling fluidized bed adsorbers. Industrial & Engineering Chemistry Research, 2015, 54(27): 6959–6974

[17] Wang H , Li Z , Li Y , Cai N . Reduced-order model for CaO carbonation kinetics measured using micro-fluidized bed thermogravimetric analysis. Chemical Engineering Science, 2021, 229: 116039

[18] Yuan T , Cizmas P G , O’Brien T . A reduced-order model for a bubbling fluidized bed based on proper orthogonal decomposition. Computers & Chemical Engineering, 2005, 30(2): 243–259

[19] Li C , Dai Z , Sun Z , Wang F . Modeling of an opposed multiburner gasifier with a reduced-order model. Industrial & Engineering Chemistry Research, 2013, 52(16): 5825–5834

[20] Saastamoinen J J . Simplified model for calculation of devolatilization in fluidized beds. Fuel, 2006, 85(17-18): 2388–2395

[21] Kaushal P , Abedi J . A simplified model for biomass pyrolysis in a fluidized bed reactor. Journal of Industrial and Engineering Chemistry, 2010, 16(5): 748–755

[22] Gómez-Barea A , Leckner B . Modeling of biomass gasification in fluidized bed. Progress in Energy and Combustion Science, 2010, 36(4): 444–509

[23] Kaushal P , Tyagi R . Advanced simulation of biomass gasification in a fluidized bed reactor using ASPEN PLUS. Renewable Energy, 2017, 101: 629–636

[24] Nikku M , Bordbar H , Myöhänen K , Hyppänen T . Effects of heterogeneous flow on carbon conversion in gas-solid circulating fluidized beds. Fuel, 2020, 280: 118623

[25] Sternéus J , Johnsson F , Leckner B . Characteristics of gas mixing in a circulating fluidised bed. Powder Technology, 2002, 126(1): 28–41

[26] Chirone R , Miccio F , Scala F . On the relevance of axial and transversal fuel segregation during the FB combustion of a biomass. Energy & Fuels, 2004, 18(4): 1108–1117

[27] OkeOLettieriPSalatinoPMazzeiL. CFD simulations of lateral solid mixing in fluidized beds. CFB-11: Proceedings of the 11th International Conference on Fluidized Bed Technology, 2014, 287–292

[28] Oke O , Lettieri P , Salatino P , Solimene R , Mazzei L . Eulerian modeling of lateral solid mixing in gas-fluidized suspensions. Procedia Engineering, 2015, 102: 1491–1499

[29] Vandewalle L A , Francia V , Van Geem K M , Marin G B , Coppens M O . Solids lateral mixing and compartmentalization in dynamically structured gas-solid fluidized beds. Chemical Engineering Journal, 2022, 430: 133063

[30] Luo G , Cheng L , Ma Z , Li L , Li Z , Wang P , Li L , Rong H . MP-PIC simulation on solid dispersion in a 350 MW CFB boiler. Industrial & Engineering Chemistry Research, 2022, 61(45): 16857–16868

[31] Luo G , Cheng L , Kang Q , Zhang Q , Li K , Guo Q , Li W . Investigation on solid dispersion in a CFB dense region with bluetooth tracking method and MP-PIC simulation. Powder Technology, 2023, 429: 118892

[32] Liu D , Chen X . Lateral solids dispersion coefficient in large-scale fluidized beds. Combustion and Flame, 2010, 157(11): 2116–2124

[33] Sette E , Pallarès D , Johnsson F . Experimental evaluation of lateral mixing of bulk solids in a fluid-dynamically down-scaled bubbling fluidized bed. Powder Technology, 2014, 263: 74–80

[34] Oke O , Van Wachem B , Mazzei L . Lateral solid mixing in gas-fluidized beds: CFD and DEM studies. Chemical Engineering Research & Design, 2016, 114: 148–161

[35] BakshiA. Multiscale continuum simulations of fluidization: bubbles, mixing dynamics and reactor scaling. Dissertation of PhD degree. Boston: Massachusetts Institute of Technology, 2017

[36] Askarishahi M , Salehi M S , Molaei Dehkordi A . Numerical investigation on the solid flow pattern in bubbling gas-solid fluidized beds: effects of particle size and time averaging. Powder Technology, 2014, 264: 466–476

[37] Martinez Castilla G , Larsson A , Lundberg L , Johnsson F , Pallarès D . A novel experimental method for determining lateral mixing of solids in fluidized beds—quantification of the splash-zone contribution. Powder Technology, 2020, 370: 96–103

[38] PallarèsDDíezPJohnssonF. Experimental analysis of fuel mixing patterns in a fluidized bed. The 12th International Conference on Fluidization-New Horizons in Fluidization Engineering, 2007

[39] Norouzi H R , Mostoufi N , Mansourpour Z , Sotudeh-Gharebagh R , Chaouki J . Characterization of solids mixing patterns in bubbling fluidized beds. Chemical Engineering Research & Design, 2011, 89(6): 817–826

[40] Olsson J , Pallarès D , Johnsson F . Lateral fuel dispersion in a large-scale bubbling fluidized bed. Chemical Engineering Science, 2012, 74: 148–159

[41] Farzaneh M , Almstedt A E , Johnsson F , Pallarès D , Sasic S . The crucial role of frictional stress models for simulation of bubbling fluidized beds. Powder Technology, 2015, 270: 68–82

[42] Ostermeier P , DeYoung S , Vandersickel A , Gleis S , Spliethoff H . Comprehensive investigation and comparison of TFM, DenseDPM and CFD-DEM for dense fluidized beds. Chemical Engineering Science, 2019, 196: 291–309

RIGHTS & PERMISSIONS

The Author(s) 2024. This article is published with open access at link.springer.com and journal.hep.com.cn