3D computational simulation of solid distribution characteristics in dual circulating fluidized bed

doi:10.7523/j.issn.2095-6134.2016.02.018

Abstract

Abstract:

Three dimensional computational simulation based on Euler multiphase flow model was carried out for the gas-solid flow in dual circulating fluidized bed. The results suggested that the solid distributions along x-axis direction in both air reactor (AR) and fuel reactor (FR) showed obvious asymmetry due to the influences of connecting structures. The solid concentration in the near-wall region in x-axis positive direction in FR decreased rapidly with FR fluidization rate and the trend became stable after FR fluidization flow rate reached 12.5 m³/h. Meanwhile, the solid concentration in the near-wall region in x-axis negative direction increased first and then decreased. The solid concentration in the near-wall regions in both z-axis positive and negative directions in FR decreased with FR fluidization flow rate.

Key words: dual circulating fluidized bed, gas-solid flow, computational simulation, solid distribution

CLC Number:

O359

GENG Chamin, ZHONG Wenqi, SHAO Yingjuan, CHEN Dailin, JIN Baosheng. 3D computational simulation of solid distribution characteristics in dual circulating fluidized bed[J]. , 2016, 33(2): 258-264.

References

[1] Kolbitsch P, Pröll T, Bolhar-Nordenkampf J, et al. Design of a chemical looping combustor using a dual circulating fluidized bed (DCFB) reactor system[J]. Chemical Engineering & Technology, 2009, 32(3): 398-403.
[2] Seo M W, Goo J H, Kim S D, et al. Gasification characteristics of coal/biomass blend in a dual circulating fluidized bed reactor[J]. Energy & Fuels, 2010, 24(5): 3 108-3 118.
[3] Pröll T, Kolbitsch P, Bolhàr-Nordenkampf J, et al. A novel dual circulating fluidized bed system for chemical looping processes[J]. AIChE journal, 2009, 55(12): 3 255-3 266.
[4] 初雷哲, 范晓旭, 肖琦, 等. 双循环流化床生物质解耦气化实验[J]. 农业机械学报, 2010, 41: 117-120.
[5] 于旷世. 循环流化床双床煤气化工艺试验研究[D]. 北京:中国科学院工程热物理研究所, 2012.
[6] Syamlal M, Rogers W, O'Brien T J. MFIX documentation: theory guide J. Technical Note[R]. DOE/METC-94/1004, NTIS/DE94000087, National Technical Information Service, Springfield, VA, 1993.
[7] Schaeffer D G. Instability in the evolution equations describing incompressible granular flow[J]. Journal of Differential Equations, 1987, 66(1): 19-50.
[8] Srivastava A, Sundaresan S. Analysis of a frictional-kinetic model for gas-particle flow[J]. Powder Technology, 2003, 129(1): 72-85.
[9] Wang S, Yang Y, Lu H, et al. Computational fluid dynamic simulation based cluster structures-dependent drag coefficient model in dual circulating fluidized beds of chemical looping combustion[J]. Industrial & Engineering Chemistry Research, 2012, 51(3): 1 396-1 412.
[10] Lun C K K, Savage S B, Jeffrey D J, et al. Kinetic theories for granular flow: inelastic particles in Couette flow and slightly inelastic particles in a general flowfield[J]. Journal of Fluid Mechanics, 1984, 140: 223-256.
[11] Syamlal M, O'Brien T J. The derivation of a drag coefficient formula from velocity-voidage correlations[R]. Department of Energy, Office of Fossil Energy, Technical report, 1994.
[12] Wen C, Yu Y H. Mechanics of fluidization[J]. Chem Eng Prog Symp Ser, 2014, 62(62): 100.
[13] Gidaspow D. Multiphase flow and fluidization: continuum and kinetic theory descriptions[M]. Academic Press, 1994.
[14] Pröll T, Rupanovits K, Kolbitsch P, et al. Cold flow model study on a dual circulating fluidized bed (DCFB) system for chemical looping processes[J]. Chemical Engineering & Technology, 2009, 32(3): 418-424.
[15] Kolbitsch P, Pröll T, Bolhar-Nordenkampf J, et al. Design of a chemical looping combustor using a dual circulating fluidized bed (DCFB) reactor system[J]. Chemical Engineering & Technology, 2009, 32(3): 398-403.
[16] Guío-Pérez D C, Hofbauer H, Pröll T. Effect of ring-type internals on solids distribution in a dual circulating fluidized bed system-cold flow model study[J]. AIChE Journal, 2013, 59(10): 3 612-3 623.
[17] Schmid J C, Pröll T, Pfeifer C, et al, Improvement of gas-solid interaction in dual circulating fluidized bed systems[C]//Proc. 9th European Conference on Industrial Furnaces and Boilers (INFUB). Estoril, Portugal, 2011.