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Uncertainty evaluation by gamma transmission measurements and CFD model comparison in a FCC cold pilot unit

Published online by Cambridge University Press:  05 June 2013

C.C. Dantas ,
A.E. Moura ,
H.J.B. de Lima Filho ,
S.B. Melo ,
V.A. Dos Santos  and
E.A.O. Lima
C.C. Dantas*
Affiliation:
Department of Nuclear Energy-DEN/UFPE, Federal University of Pernambuco, Recife, Pernambuco, Brazil
A.E. Moura
Affiliation:
Department of Nuclear Energy-DEN/UFPE, Federal University of Pernambuco, Recife, Pernambuco, Brazil
H.J.B. de Lima Filho
Affiliation:
Department of Chemical Engineering-DEQ/UFPE, Federal University of Pernambuco, Recife, Pernambuco, Brazil
S.B. Melo
Affiliation:
Informatics Center-CIN/UFPE, Federal University of Pernambuco, Recife, Pernambuco, Brazil
V.A. Dos Santos
Affiliation:
Department of Chemistry-UNICAPE, Catholic University of Pernambuco, Recife, Pernambuco, Brazil
E.A.O. Lima
Affiliation:
Department of Mathematics-UPE, Universidade de Pernambuco, Recife, Pernambuco, Brazil
*
⋆ Correspondence: [email protected]
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Abstract

The solid flow in air-catalyst in circulating fluidized bed was simulated with CFD model to obtain axial and radial distribution. Therefore, project parameters were confirmed and steady state operation condition was improved. Solid holds up axial end radial profiles simulation and comparison with gamma transmission measurements are in a good agreement. The transmission signal from an 241Am radioactive source was evaluated in NaI(Tl) detector coupled to multichannel analyzer. This non intrusive measuring set up is installed at riser of a cold pilot unit to determine parameters of FCC catalyst flow at several concentrations. Mass flow rate calculated by combining solid hold up and solid phase velocity measurements was compared with catalyst inlet measured at down-comer. Evaluation in each measured parameter shows that a relative combined uncertainty of 6% in a 95% interval was estimated. Uncertainty analysis took into account a significant correlation in scan riser transmission measurements. An Eulerian approach of CFD model incorporating the kinetic theory of granular flow was adopted to describe the gas–solid two-phase flows in a multizone circulating reactor. Instantaneous and local gas-particle velocity, void fraction and turbulent parameters were obtained and results are shown in 2 D and 3D graphics.

Keywords

FCC fluid dynamicsgamma ray scannerCFD simulationuncertainty valuationsolid flow
Type
Research Article
Information
International Journal of Metrology and Quality Engineering , Volume 4 , Issue 1 , 2013 , pp. 9 - 15
Copyright
© EDP Sciences 2013

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