Modeling of Sulfided Zinc Titanate Regeneration in a Fluidized-Bed Reactor. 1. Determination of the Solid Conversion Rate Model Parameters

1997 ◽  
Vol 36 (12) ◽  
pp. 5432-5438 ◽  
Author(s):  
J. T. Konttinen ◽  
C. A. P. Zevenhoven ◽  
K. P. Yrjas ◽  
M. M. Hupa
Keyword(s):  
Fluidized Bed ◽  
Conversion Rate ◽  
Fluidized Bed Reactor ◽  
Model Parameters ◽  
Rate Model ◽  
Zinc Titanate

Design and Startup of an Anaerobic Fluidized Bed Reactor

1999 ◽  
Vol 40 (8) ◽  
pp. 63-70 ◽  
Author(s):  
P. Marín ◽  
D. Alkalay ◽  
L. Guerrero ◽  
R. Chamy ◽  
M. C. Schiappacasse
Keyword(s):  
Fluidized Bed ◽  
Hydraulic Retention Time ◽  
Fluidized Bed Reactor ◽  
Gas Production ◽  
Beach Sand ◽  
Organic Load ◽  
Load Rate ◽  
Anaerobic Fluidized Bed Reactor ◽  
Bed Expansion

A 10 1 anaerobic fluidized bed reactor (AFBR) was designed and constructed, using beach sand as the solid support for the biomass. Considering the complexity of this type of system, previously to the startup, several experiences were performed in a series of minireactors, such as: determination of the bed expansion and the feed distribution. The startup was made increasing gradually the organic load rate (OLR), using the alkalinity ratio (α) and the removal of the organic load, as mg/l of COD, as leading parameters. The system attained a COD removal of over 85%, for an OLR of 3.4 [kg COD/m3·d]. The best removal of 92% was obtained at an OLR of 1.04 [kg COD/m3·d], with a hydraulic retention time (HRT) of 12 hours. The best gas production of 1.8 [m3 of biogas/m3·d], equivalent to a production of 0.16 [m3/kg CODremoved], was obtained at an (HRT) of 4.8 hours. The best startup results were obtained using Ethanol as the Carbon source.

Determination of the mixing coefficient in a fluidized bed reactor

1965 ◽  
Vol 8 (5) ◽  
pp. 427-430
Author(s):  
I. A. Burovoi ◽  
G. I. Svetozarova
Keyword(s):  
Fluidized Bed ◽  
Fluidized Bed Reactor ◽  
Mixing Coefficient

scholarly journals Particle tracking in a Two-Section Two-Zone Fluidized Bed Reactor (TS-TZFBR). Experimental technique and CCBM model validation

1970 ◽  
pp. 38
Author(s):  
I. Julián ◽  
J. Herguido ◽  
M. Menéndez
Keyword(s):  
Fluidized Bed ◽  
Process Integration ◽  
Fluid Dynamic ◽  
Fluidized Bed Reactor ◽  
Catalyst Regeneration ◽  
Model Parameters ◽  
Mixing Rate ◽  
Cross Sectional ◽  
Operational Conditions ◽  
Optical Tracers

The Two Zone Fluidized Bed Reactor (TZFBR) provides a high level of process integration, allowing reaction and, in situ, continuous catalyst regeneration, in a single fluidized bed. Reactive and regenerative atmospheres are induced simultaneously inside the single vessel due to a separated gas inlet and particles fluidization provides reactor continuous operation. Therefore, the fluid dynamic key factor in a TZFBR is the mixing rate between solids inside the two bed zones (a good mixture provides continuous catalyst regeneration, while bad contact between bed zones leads to deactivation and loss of catalytic surface). In the present study, phosphorescent particles have been used as optical tracers to measure solids axial mixing between reactor zones in a catalytic TZFBR. Additionally, a different cross-sectional area between zones has been studied to get a certain fluidization regime, allowing small flowrates in the regeneration zone. This geometry implied a transition angle α between zones to be implemented (Two-Section TZFBR). In line with it, a modified counter-current backmixing model (CCBM) without fitting parameters was developed to predict mixture rates inside the bed for different TS-TZFBR geometries. Modifications carried out in the CCBM basis model involved reactor geometry and the presence of two simultaneous gas feed points along the bed. Model parameters related to bubble/solid fraction and wake-emulsion mass transfer were fully correlated to operational conditions (gas velocity, feed point location and section change). The adapted CCBM model predictions were further validated with optical tracers experimental fluid dynamic data, resulting in a high agreement.

Determination of optimal biofilm activity in a biological fludized bed (BFB) reactor

1994 ◽  
Vol 29 (10-11) ◽  
pp. 347-351 ◽  
Author(s):  
B. Ruggeri ◽  
G. Caire ◽  
V. Specchia ◽  
G. Sassi ◽  
F. Bosco ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Fluidized Bed ◽  
Experimental Tests ◽  
Fluidized Bed Reactor ◽  
Solid Mass ◽  
Specific Biomass ◽  
Biomass Activity ◽  
Reaction Regime ◽  
Bed Expansion

Experimental tests were carried out in order to ascertain the biomass activity in a biological fluidized bed reactor. A semi-pilot fluidized bed reactor was used with two different supports (sand and glass particles). The specific biomass activity was followed during the tests. It reached a maximum and after declined vs. biomass hold up and bed expansion. The results clearly put in evidence as the activity is strongly effected by liquid-solid mass transfer and support roughness which in turn determines the compactness of biofilm and its diffusive properties. By controlling the bed expansion it is possible to decide the macro reaction regime of work: external mass transfer, biokinetics or diffusive control according to incoming substrate concentration, in order to maximize the bioreactor performance.

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