Effect of ring‐type internals on solids distribution in a dual circulating fluidized bed system—cold flow model study

The redistribution of solids in a counter-current circulating fluidized bed (CFB) by effect of ring-type internals was investigated in a downscaled cold-flow model. The system consists of two interconnected CFB reactors, in which the primary reactor operates like a common riser while the secondary reactor operates in counter-current. The unit works without circulation rate control devices and the inventory splits inherently between the two reactors by pressure balance and depending on the fluidization velocities. Previous studies showed an increment in the total pressure drop in the secondary reactor as result of the internals installation. With the purpose of obtaining comparable inventory in the secondary reactor with and without rings, a device for adjustment of total inventory was designed and installed. Effects of the aperture ratio, number of rings, fluidization velocity, and particles circulation rate were studied. The results obtained approach a guideline for the detailed design of similar configurations. © 2013 American Institute of Chemical Engineers AIChE J, 59: 3612–3623, 2013

[1]  L. R. Glicksman,et al.  Scaling relationship for fluidized beds , 1984 .

[2]  Rex B. Thorpe,et al.  Gas–solids flow in the diffuser of a circulating fluidised bed riser , 2000 .

[3]  J. Bu,et al.  Influence of ring‐type internals on axial pressure distribution in circulating fluidized bed , 1999 .

[4]  Leon R. Glicksman,et al.  Scaling relationships for fluidized beds , 1984 .

[5]  Anders Lyngfelt,et al.  Natural minerals as oxygen carriers for chemical looping combustion in a dual circulating fluidized bed system , 2009 .

[6]  L. Glicksman,et al.  The effect of bed diameter on near-wall hydrodynamics in scale-model circulating fluidized beds , 2000 .

[7]  A. Lyngfelt,et al.  A fluidized-bed combustion process with inherent CO2 separation; Application of chemical-looping combustion , 2001 .

[8]  Jesse Zhu,et al.  Radial and axial voidage distributions in circulating fluidized bed with ring-type internals , 1997 .

[9]  H. Hofbauer,et al.  Design of a Chemical Looping Combustor using a Dual Circulating Fluidized Bed (DCFB) Reactor System , 2009 .

[10]  Wen-Ching Yang,et al.  Exploratory Design Study on Reactor Configurations for Carbon Dioxide Capture from Conventional Power Plants Employing Regenerable Solid Sorbents , 2009 .

[11]  Hsiaotao Bi,et al.  Hydrodynamics of turbulent fluidized beds of different diameters , 2004 .

[12]  Hermann Hofbauer,et al.  Cold Flow Model Study on a Dual Circulating Fluidized Bed (DCFB) System for Chemical Looping Processes , 2009 .

[13]  Hsiaotao Bi,et al.  Baffle effects on performance of catalytic circulating fluidized bed reactor , 1991 .

[14]  Hermann Hofbauer,et al.  A novel dual circulating fluidized bed system for chemical looping processes , 2009 .