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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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References

Knowlton, T.M., Tools and techniques for diagnosing and solving operating problems in fluidized bed systems, Oil Gas Sci. Tech. 55, 209–217 (2000) CrossRefGoogle Scholar
Arastoopour, H., Gisdaspow, D., Vertical pneumatic using four hydrodynamic models, Ind. Eng. Chem. 18, 123−130 (1979) Google Scholar
Khadzhiev, S.N., Gerzeliev, I.M., Kapustin, V.M., Kadiev, Kh.M., Dement’ev, K.I., Pakhmanova, O.A., Catalytic cracking in today’s deep-conversion refinery, Petro. Chem. 51, 32–38 (2011) CrossRefGoogle Scholar
dos Santos, V.A., Dantas, C.C., Luna-Finkler, C.L., de Souza, J.E.G., Principal component analysis in an experimental cold flow model of a fluid catalytic cracking unit by gammametry, Prog. Nucl. Energy 53, 1114–1118 (2011) CrossRefGoogle Scholar
D.C. Montgomery, Design and Analysis of Experiments, 4th edn. (John Wiley & Sons, 1997)
Derouin, C., Nevicato, D., Forissier, M., Wild, M.G., Bernard, J., Hydrodynamics of riser units and their impact on FCC operation, Ind. Eng. Chem. Res. 36, 4504–4511 (1997) CrossRefGoogle Scholar
IAEA – International Atomic Energy Agency, Industrial Process Gamma Tomography (IAEA-TECDOC-1589, 2007)
Dantas, C.C., Narain, R., dos Santos, V.A., de Melo, A.C.B.A., Catalyst concentration distribution in fluidized bed by gamma-ray absorption, J. Radioanal. Nucl. Chem. 269, 425 (2006) CrossRefGoogle Scholar
Dantas, C.C., Narain, R., dos Santos, V.A., de Melo, A.C.B.A., Grieken, R.V., Precise gamma ray measurements of the radial distribution of a cracking catalyst at diluted concentrations in a glass riser, Nucl. Instrum. Methods Phys. Res. B, Beam Interact. Mater. Atoms 251, 201–208 (2006) Google Scholar
Dantas, C.C., Melo, S.B., Oliveira, E.F., Simões, F.B.P., dos Santos, M.G., Santos, V.A., Measurement of density distribution of a cracking catalyst in experimental riser with a sampling procedure for gamma ray tomography, Nucl. Instrum. Methods Phys. Res. B 266, 841–848 (2008) CrossRefGoogle Scholar
Vasconcelos, G.V., Melo, S.B., Dantas, C.C., Malta, I., Oliveira, R., Oliveira, E.F., A particle system approach to industrial topographic reconstruction, Meas. Sci. Technol. 22, 104003–104010 (2011) CrossRefGoogle Scholar
Harris, B.J., Davidson, J.F., Xue, Y., Axial and radial variations of flow in circulating fluidized bed risers, CFB Tech. IV, 103–110 (1994) Google Scholar
Mostoufi, N., Chaouki, J., Flow structure of solids in gas-solid fluidized beds, Chem. Eng. Sci. 59, 4217–4227 (2004) CrossRefGoogle Scholar
Nova, S., Krol, S., de Lasa, H., Particle velocity and particle clustering in down-flow reactors, Power Technol. 148, 172–185 (2004) CrossRefGoogle Scholar
Wang, Q.H., Gao, Q., Shi, H.S., Wu, X.C., Luo, Z.Y., Cen, K.F., Formation, structure and motion of clusters in circulating fluidized bed, J. Zhejiang University (Eng. Sci.) 40, 118–122 (2006) Google Scholar
Rhodes, M.J., Geldart, D., Model for the CFB, Power Technol. 53, 155–162 (1987) CrossRefGoogle Scholar
Horio, M., Morishita, K., Tachibana, O., Murata, N., Solid distribution and movement in CFBs, CFB Tech. II, 147–154 (1988)Google Scholar