Documents disponibles écrits par cet auteur

CFD modeling of nucleation, growth, aggregation, and breakage in continuous precipitation of barium sulfate in a stirred tank / Jingcai Cheng in Industrial & engineering chemistry research, Vol. 48 N° 15 (Août 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 15 (Août 2009) . - pp. 6992–7003 Titre : CFD modeling of nucleation, growth, aggregation, and breakage in continuous precipitation of barium sulfate in a stirred tank Type de document : texte imprimé Auteurs : Jingcai Cheng, Auteur ; Chao Yang, Auteur ; Zai-Sha Mao, Auteur Année de publication : 2009 Article en page(s) : pp. 6992–7003 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Barium  sulfate  (BaSO4)  Continuous  stirred  tank  reactor  Single-phase  Reynolds  Navier−Stokes  equations Résumé : In this work, the precipitation of barium sulfate (BaSO4) in a continuous stirred tank reactor (CSTR) is modeled. The flow field is obtained through solving the single-phase Reynolds averaged Navier−Stokes equations with a standard single-phase k−ε turbulence model. The population balance equation is solved through the standard method of moments (SMM) and the quadrature method of moments (QMOM) both with and without aggregation and breakage terms. In the cases of precipitation simulation without aggregation and breakage, the results predicted from 2-node QMOM, 3-node QMOM, and SMM are very close. Thus, 2-node QMOM could replace SMM and be well-incorporated into an in-house CFD code to simulate the precipitation in CSTR with acceptable accuracy. The predicted area-averaged crystal size d32 decreases almost linearly with increasing feed concentration, and the deviation from experimental data becomes significant at high feed concentration. Numerical simulation using 2-node QMOM with the Brownian motion and shear-induced aggregation kernels as well as a power-law breakage kernel indicates that the predicted d32 shows good qualitative agreement with experimental results, and the quantitative agreement is achieved when the appropriate breakage rate equation is adopted. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9004282 [article] CFD modeling of nucleation, growth, aggregation, and breakage in continuous precipitation of barium sulfate in a stirred tank [texte imprimé] / Jingcai Cheng, Auteur ; Chao Yang, Auteur ; Zai-Sha Mao, Auteur . - 2009 . - pp. 6992–7003. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 15 (Août 2009) . - pp. 6992–7003 Mots-clés : Barium  sulfate  (BaSO4)  Continuous  stirred  tank  reactor  Single-phase  Reynolds  Navier−Stokes  equations Résumé : In this work, the precipitation of barium sulfate (BaSO4) in a continuous stirred tank reactor (CSTR) is modeled. The flow field is obtained through solving the single-phase Reynolds averaged Navier−Stokes equations with a standard single-phase k−ε turbulence model. The population balance equation is solved through the standard method of moments (SMM) and the quadrature method of moments (QMOM) both with and without aggregation and breakage terms. In the cases of precipitation simulation without aggregation and breakage, the results predicted from 2-node QMOM, 3-node QMOM, and SMM are very close. Thus, 2-node QMOM could replace SMM and be well-incorporated into an in-house CFD code to simulate the precipitation in CSTR with acceptable accuracy. The predicted area-averaged crystal size d32 decreases almost linearly with increasing feed concentration, and the deviation from experimental data becomes significant at high feed concentration. Numerical simulation using 2-node QMOM with the Brownian motion and shear-induced aggregation kernels as well as a power-law breakage kernel indicates that the predicted d32 shows good qualitative agreement with experimental results, and the quantitative agreement is achieved when the appropriate breakage rate equation is adopted. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9004282

Experimental study on liquid–liquid macromixing in a stirred tank / Yanchun Zhao in Industrial & engineering chemistry research, Vol. 50 N° 10 (Mai 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 10 (Mai 2011) . - pp. 5952-5958 Titre : Experimental study on liquid–liquid macromixing in a stirred tank Type de document : texte imprimé Auteurs : Yanchun Zhao, Auteur ; Xiangyang Li, Auteur ; Jingcai Cheng, Auteur Année de publication : 2011 Article en page(s) : pp. 5952-5958 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Stirred  vessel  Macromixing Résumé : In this paper, the experimental data on the mixing time and power consumption of two immiscible liquids in a mechanically agitated baffled tank are presented. The electric conductivity method was taken for the measurement of the mixing time and the shaft-torque method for the power consumption measurement Tap water was used as the continuous phase and kerosene the dispersed phase. The effects of the agitation speed, type of impeller, clearance of the impeller off the tank bottom, volume fraction of the dispersed phase, physical properties of the liquids, and probe position on the macromixing of the liquid-liquid system were studied. The phenomena of macromixing are largely similar to those of single-liquid and gas-liquid stirred tanks. The experiment indicates that the flow field and turbulence can be dampened at high volume fraction of the dispersed phase while enhanced at low percentage. The mixing time becomes longer with increasing viscosity of the dispersed phase. The results show that the pitched blade turbine downflow is more efficient for macromixing than the others tested in this work. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24158892 [article] Experimental study on liquid–liquid macromixing in a stirred tank [texte imprimé] / Yanchun Zhao, Auteur ; Xiangyang Li, Auteur ; Jingcai Cheng, Auteur . - 2011 . - pp. 5952-5958. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 10 (Mai 2011) . - pp. 5952-5958 Mots-clés : Stirred  vessel  Macromixing Résumé : In this paper, the experimental data on the mixing time and power consumption of two immiscible liquids in a mechanically agitated baffled tank are presented. The electric conductivity method was taken for the measurement of the mixing time and the shaft-torque method for the power consumption measurement Tap water was used as the continuous phase and kerosene the dispersed phase. The effects of the agitation speed, type of impeller, clearance of the impeller off the tank bottom, volume fraction of the dispersed phase, physical properties of the liquids, and probe position on the macromixing of the liquid-liquid system were studied. The phenomena of macromixing are largely similar to those of single-liquid and gas-liquid stirred tanks. The experiment indicates that the flow field and turbulence can be dampened at high volume fraction of the dispersed phase while enhanced at low percentage. The mixing time becomes longer with increasing viscosity of the dispersed phase. The results show that the pitched blade turbine downflow is more efficient for macromixing than the others tested in this work. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24158892