HYDRODYNAMIC SIMULATION AND EXPERIMENTAL STUDIES OF AN INTERNALLY CIRCULATING BUBBLING FLUIDIZED BED WITH CONCENTRIC CYLINDERS

J P SImanjuntak

Abstract


This paper presents hydrodynamic simulation and experimental studies of gas–solid flow in an internally circulating bubbling fluidized bed (ICBFB) using concentric cylinders. An Eulerian–Eulerian Model (EEM) incorporating the kinetic theory of granular flow (KTGF) was applied in order to simulate the gas–solid flow behavior. The gas and solid dynamic was simulated using a computational fluid dynamics (CFD) software package, Fluent 6.3. Three–dimensional (3D) geometry was used to represent the key parts of a pilot scale of this reactor. Simulations were conducted to investigate the effect of the changes of six operating parameters: the fluidization flow rate of the draft tube (Qdt), the aeration flow rate of the annulus (Qan), the initial bed static height (Hbs), the draft tube height (Hdt), the draft tube diameter (Ddt), and the orifice diameter (Dor) on the solid flow characteristics in terms of the solid circulation rate (Gs). The results were then validated with the experimental results. All the investigated operating parameters have strong effect on Gs.

 

Keywords: Concentric cylinders fluidized bed; Solid circulation rate; Finite volume approach; ANSYS/Fluent


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Kuramoto, M., D. Kunii, and T. Furusawa, Flow of dense fluidized particles through an opening in a circulation system. Powder Technology, 1986. 47(2): p. 141-149.

Loffler, G., et al., Hydrodynamics of a dual fluidized-bed gasifier Part I: simulation of a riser with gas injection and diffuser. Chemical Engineering Science, 2003. 58(18): p. 4197-4213.

Murakami, T., et al., Some process fundamentals of biomass gasification in dual fluidized bed. Fuel, 2007. 86(1-2): p. 244-255.

Fang, M., et al., Experimental research on solid circulation in a twin fluidized bed system. Chemical Engineering Journal, 2003. 94(3): p. 171-178.

Foscolo, P., et al., Design and cold model testing of a biomass gasifier consisting of two interconnected fluidized beds. Powder Technology, 2007. 173(3): p. 179-188.

Zhou, Z.-q., et al., Study on biomass circulation and gasification performance in a clapboard-type internal circulating fluidized bed gasifier. Biotechnology Advances, 2009. 27(5): p. 612-615.

Luo, K., et al., LES–DEM investigation of an internally circulating fluidized bed: Effects of gas and solid properties. Chemical Engineering Journal, 2013. 228(0): p. 583-595.

Xiao, X., et al., Multi-stage biomass gasification in Internally Circulating Fluidized-bed Gasifier (ICFG): Test operation of animal-waste-derived biomass and parametric investigation at low temperature. Fuel Processing Technology, 2010. 91(8): p. 895-902.

Corella, J., J. Toledo, and G. Molina, Biomass gasification with pure steam in fluidised bed: 12 variables that affect the effectiveness of the biomass gasifier. International Journal of Oil, Gas and Coal Technology, 2008. 1(1): p. 194-207.

Berruti, F., J. Muir, and L. Behie, Solids circulation in a spout-fluid bed with draft tube. The Canadian Journal of Chemical Engineering, 1988. 66(6): p. 919-923.

Song, B., Y. Kim, and S. Kim, Circulation of solids and gas bypassing in an internally circulating fluidized bed with a draft tube. Chemical Engineering Journal, 1997. 68(2-3): p. 115-122.

Zhang, H., et al., Hydrodynamics of a novel biomass autothermal fast pyrolysis reactor: Solid circulation rate and gas bypassing. Chemical Engineering Journal, 2012. 181–182(0): p. 685-693.

Mathiensen, V., Solberg, T., Hjertager, B.H. An experimental and computational study of multiphase flow behavior in a circulating fluidized bed. International Journal of Multiphase Flow, 2000. 26: p. 387-419.

Feng, Y., et al., CFD modeling of gas-solid flow in an internally circulating fluidized bed. Powder Technology, 2012. 219: p. 78-85.

Ding, J. and D. Gidaspow, A bubbling fluidization model using kinetic theory of granular flow. AIChE Journal, 1990. 36(4): p. 523-538.

Rovero, G., N. Piccinini, and A. Lupo, Particles Velocity in Full and Semicylindrical Sprouted Bed. Vitesses des particulales dans les list a jet tri-dimensionels et semi cylindriques, 1985. 21(124): p. 43-49.

Yang, W. and D. Keairns. Recirculating fluidized bed reactor data utilizing a two-dimensional cold model. in AIChE Symp. Ser. 1974.

Tallon, S. and C. Davies, Discharge of a fluidised bed of particles through an orifice. Powder Technology, 2005. 160(1): p. 45-53.


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