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CO2 Capture and Hydrogen Production in an Integrated Fluidized Bed Reformer-Regenerator System / Zhongxiang Chen in Industrial & engineering chemistry research, Vol. 50 N° 8 (Avril 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 8 (Avril 2011) . - pp. 4716–4721 Titre : CO2 Capture and Hydrogen Production in an Integrated Fluidized Bed Reformer-Regenerator System Type de document : texte imprimé Auteurs : Zhongxiang Chen, Auteur ; John R. Grace, Auteur ; C. Jim Lim, Auteur Année de publication : 2011 Article en page(s) : pp. 4716–4721 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : CO2  capture  hydrogen  Regenerator  system Résumé : Thermodynamic analysis of CO2 capture and hydrogen production for steam methane reforming was carried out using ASPEN simulation software. The integrated reaction system is composed of a sorbent-enhanced fluidized bed reformer coupled with a fluidized bed sorbent regenerator (calciner) where fine CaO-based sorbents (100 μm mean particle diameter) were used. The system performance is evaluated as a function of a number of operating parameters for both the reformer and regenerator. The results indicate that the optimum operating parameters for reformer are temperatures from 550 to 600 °C, low pressure, steam-to-carbon molar feed ratio of 3.5, and sorbent circulation flow rate exceeding the minimum stoichiometric feed rate of active sorbent. For the sorbent regenerator, the optimum conditions are temperatures above 850 °C, low pressure, and enough sweep gas flow to completely calcine CaCO3. On the basis of thermodynamics, it should be possible to achieve a hydrogen purity of 98% and a CO2 purity in excess of 99% after condensing sweep steam downstream. The predicted hydrogen purity is consistent with previous experiments. The high-concentration CO2 should be suitable for sequestration or for industrial use. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie101360x [article] CO2 Capture and Hydrogen Production in an Integrated Fluidized Bed Reformer-Regenerator System [texte imprimé] / Zhongxiang Chen, Auteur ; John R. Grace, Auteur ; C. Jim Lim, Auteur . - 2011 . - pp. 4716–4721. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 8 (Avril 2011) . - pp. 4716–4721 Mots-clés : CO2  capture  hydrogen  Regenerator  system Résumé : Thermodynamic analysis of CO2 capture and hydrogen production for steam methane reforming was carried out using ASPEN simulation software. The integrated reaction system is composed of a sorbent-enhanced fluidized bed reformer coupled with a fluidized bed sorbent regenerator (calciner) where fine CaO-based sorbents (100 μm mean particle diameter) were used. The system performance is evaluated as a function of a number of operating parameters for both the reformer and regenerator. The results indicate that the optimum operating parameters for reformer are temperatures from 550 to 600 °C, low pressure, steam-to-carbon molar feed ratio of 3.5, and sorbent circulation flow rate exceeding the minimum stoichiometric feed rate of active sorbent. For the sorbent regenerator, the optimum conditions are temperatures above 850 °C, low pressure, and enough sweep gas flow to completely calcine CaCO3. On the basis of thermodynamics, it should be possible to achieve a hydrogen purity of 98% and a CO2 purity in excess of 99% after condensing sweep steam downstream. The predicted hydrogen purity is consistent with previous experiments. The high-concentration CO2 should be suitable for sequestration or for industrial use. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie101360x

Electrostatics generation in a small cyclone separator / Zhongxiang Chen in Industrial & engineering chemistry research, Vol. 48 N°1 (Janvier 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N°1 (Janvier 2009) . - p. 185-190 Titre : Electrostatics generation in a small cyclone separator Type de document : texte imprimé Auteurs : Zhongxiang Chen, Editeur scientifique ; Hsiaotao T. Bi, Editeur scientifique Année de publication : 2009 Article en page(s) : p. 185-190 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Electrostatics Résumé : Experiments were conducted in a small cyclone separator (50 mm inner diameter) with two grades of commercial polyethylene particles, to study the electrostatic charge generation during the gas−solid transportation and separation. Results show clearly that the charges generated in the cyclone test unit were quite reproducible. When solid particles were fed to the cyclone, there was an abrupt change in the current flow and a quick increase of (negative) charge generation for both types of polyethylene particles. Both the charge density and the charge generation rate were always higher for the particles of higher density and smaller mean size. For both types of polyethylene, the (negative) charge density increased almost linearly with the gas velocity. When the solid feed rate or initial solid loading increased, the magnitude of the charge density decreased because there were fewer particle−wall collisions at higher solids feeding rate or higher solids concentration, due to shielding effects. Results indicate that the pipe section contributed <10% of the total charge generation for both grades of polyethylene, with charge generation being dominated by the interaction between the particles and the cyclone internal surface. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie071502p [article] Electrostatics generation in a small cyclone separator [texte imprimé] / Zhongxiang Chen, Editeur scientifique ; Hsiaotao T. Bi, Editeur scientifique . - 2009 . - p. 185-190. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N°1 (Janvier 2009) . - p. 185-190 Mots-clés : Electrostatics Résumé : Experiments were conducted in a small cyclone separator (50 mm inner diameter) with two grades of commercial polyethylene particles, to study the electrostatic charge generation during the gas−solid transportation and separation. Results show clearly that the charges generated in the cyclone test unit were quite reproducible. When solid particles were fed to the cyclone, there was an abrupt change in the current flow and a quick increase of (negative) charge generation for both types of polyethylene particles. Both the charge density and the charge generation rate were always higher for the particles of higher density and smaller mean size. For both types of polyethylene, the (negative) charge density increased almost linearly with the gas velocity. When the solid feed rate or initial solid loading increased, the magnitude of the charge density decreased because there were fewer particle−wall collisions at higher solids feeding rate or higher solids concentration, due to shielding effects. Results indicate that the pipe section contributed <10% of the total charge generation for both grades of polyethylene, with charge generation being dominated by the interaction between the particles and the cyclone internal surface. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie071502p