[article] 
inIndustrial & engineering chemistry research > Vol. 49 N° 16 (Août 2010) . - pp. 7563–7573

Titre :	Thermodynamic and experimental analyses of the three - stage calcium looping process
Type de document :	texte imprimé
Auteurs :	Shwetha Ramkumar, Auteur ; Liang-Shih Fan, Auteur
Année de publication :	2010
Article en page(s) :	pp. 7563–7573
Note générale :	Industrial chemistry
Langues :	Anglais (eng)
Mots-clés :	Thermodynamic Analyses
Résumé :	Clean-coal technologies that include carbon dioxide and sulfur capture during the production of electric power, liquid fuels, and hydrogen represent a major thrust area. The calcium looping process (CLP) is one such technology that is being developed to convert syngas obtained from coal gasification to hydrogen using a regenerable calcium oxide sorbent. It integrates the water−gas shift reaction with in situ carbon dioxide, sulfur, and halide removal at high temperatures while eliminating the need for a water−gas shift catalyst and reducing the overall footprint of the hydrogen production process. The CLP comprises three reactors: the carbonation reactor, where the thermodynamic constraint of the water−gas shift reaction is overcome by the constant removal of the carbon dioxide product and high-purity hydrogen is produced with contaminant removal; the calciner, where the calcium sorbent is regenerated and a sequestration-ready carbon dioxide stream is produced; and the hydrator, where the calcined sorbent is reactivated to improve its recyclability. In this article, the reaction chemistry occurring in the three calcium looping reactors and the performance of the reactors at various process conditions are presented through thermodynamic and experimental analyses. High-purity H2 with less than 1 ppm of H2S is obtained in the carbonation stage at a stoichiometric steam-to-carbon ratio at high pressures. Although calcination of the sorbent under realistic conditions causes severe sintering and a loss in reactivity, sorbent reactivation by hydration is effective in restoring sorbent reactivity.
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie100846u

[article] Thermodynamic and experimental analyses of the three - stage calcium looping process [texte imprimé] / Shwetha Ramkumar, Auteur ; Liang-Shih Fan, Auteur . - 2010 . - pp. 7563–7573.
Industrial chemistry
Langues : Anglais (eng)
in Industrial & engineering chemistry research > Vol. 49 N° 16 (Août 2010) . - pp. 7563–7573

Mots-clés :	Thermodynamic Analyses
Résumé :	Clean-coal technologies that include carbon dioxide and sulfur capture during the production of electric power, liquid fuels, and hydrogen represent a major thrust area. The calcium looping process (CLP) is one such technology that is being developed to convert syngas obtained from coal gasification to hydrogen using a regenerable calcium oxide sorbent. It integrates the water−gas shift reaction with in situ carbon dioxide, sulfur, and halide removal at high temperatures while eliminating the need for a water−gas shift catalyst and reducing the overall footprint of the hydrogen production process. The CLP comprises three reactors: the carbonation reactor, where the thermodynamic constraint of the water−gas shift reaction is overcome by the constant removal of the carbon dioxide product and high-purity hydrogen is produced with contaminant removal; the calciner, where the calcium sorbent is regenerated and a sequestration-ready carbon dioxide stream is produced; and the hydrator, where the calcined sorbent is reactivated to improve its recyclability. In this article, the reaction chemistry occurring in the three calcium looping reactors and the performance of the reactors at various process conditions are presented through thermodynamic and experimental analyses. High-purity H2 with less than 1 ppm of H2S is obtained in the carbonation stage at a stoichiometric steam-to-carbon ratio at high pressures. Although calcination of the sorbent under realistic conditions causes severe sintering and a loss in reactivity, sorbent reactivation by hydration is effective in restoring sorbent reactivity.
ISSN :	0888-5885
En ligne :	http://pubs.acs.org/doi/abs/10.1021/ie100846u