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Carbon dioxide liquefaction process for ship transportation / Ung Lee in Industrial & engineering chemistry research, Vol. 51 N° 46 (Novembre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 46 (Novembre 2012) . - pp. 15122–15131 Titre : Carbon dioxide liquefaction process for ship transportation Type de document : texte imprimé Auteurs : Ung Lee, Auteur ; Seeyub Yang, Auteur ; Yeong Su Jeong, Auteur Année de publication : 2013 Article en page(s) : pp. 15122–15131 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Liquefaction  process Résumé : CO2 liquefaction is an essential process for long-distance ship transportation. The conventional CO2 liquefaction process employs either an external coolant or liquid expansion followed by multistage compression to obtain liquefied CO2 at low pressure. However, these processes consume considerable amounts of energy, which presents an obstacle to commercialization. Thus, the CO2 liquefaction process needs to be carefully researched and designed to reduce the operating energy. In this study, two alternative CO2 liquefaction processes are proposed and evaluated. These alternative processes use multistage expansion and multistream heat exchangers to lower the input stream temperature for the compressor. In addition, the system is operated in a more efficient manner by operating the process with an optimized compression ratio. Evaluation of the economic feasibility was performed in this study for a complete assessment of the alternative processes. As a result, about 98.1 kWh/t of CO2 was consumed for alternative process 2, which is only 91.8% of the total operating energy of existing CO2 liquefaction processes, and the CO2 liquefaction costs for alternative process 2 were reduced by 5.5%. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300431z [article] Carbon dioxide liquefaction process for ship transportation [texte imprimé] / Ung Lee, Auteur ; Seeyub Yang, Auteur ; Yeong Su Jeong, Auteur . - 2013 . - pp. 15122–15131. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 46 (Novembre 2012) . - pp. 15122–15131 Mots-clés : Liquefaction  process Résumé : CO2 liquefaction is an essential process for long-distance ship transportation. The conventional CO2 liquefaction process employs either an external coolant or liquid expansion followed by multistage compression to obtain liquefied CO2 at low pressure. However, these processes consume considerable amounts of energy, which presents an obstacle to commercialization. Thus, the CO2 liquefaction process needs to be carefully researched and designed to reduce the operating energy. In this study, two alternative CO2 liquefaction processes are proposed and evaluated. These alternative processes use multistage expansion and multistream heat exchangers to lower the input stream temperature for the compressor. In addition, the system is operated in a more efficient manner by operating the process with an optimized compression ratio. Evaluation of the economic feasibility was performed in this study for a complete assessment of the alternative processes. As a result, about 98.1 kWh/t of CO2 was consumed for alternative process 2, which is only 91.8% of the total operating energy of existing CO2 liquefaction processes, and the CO2 liquefaction costs for alternative process 2 were reduced by 5.5%. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie300431z

CO2 storage terminal for ship transportation / Ung Lee in Industrial & engineering chemistry research, Vol. 51 N° 1 (Janvier 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 1 (Janvier 2012) . - pp. 389–397 Titre : CO2 storage terminal for ship transportation Type de document : texte imprimé Auteurs : Ung Lee, Auteur ; Youngsub Lim, Auteur ; Sangho Lee, Auteur Année de publication : 2012 Article en page(s) : pp. 389–397 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : CO2  liquefaction  process Résumé : In this article, an intermediate CO2 storage system for long-distance ship transportation was modeled. The storage terminal links the continuous CO2 liquefaction process to discrete marine ship transportation and performs as a buffer between them. It is composed of four distinct processes: a CO2 input process, a storage tank and loading process, a recirculation process, and a BOG (boiled-off gas) reliquefaction process. The entire system should be operated as a liquid phase. Consequently, operation conditions, tank capacity, insulation specification, and streamflow rates play a major role in operating the storage terminal securely. The goal of this study is to design a base case of the storage terminal and propose its appropriate operation condition which makes the terminal operate with minimum operation energy. Results of the base case simulations are compared with improperly insulated systems on the pipeline and tanks that generate more BOG than the base case. The total operation energies of the base case and case studies are presented, and it turns out that approximately three times the operation energy is required if the system is not properly designed. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200762f [article] CO2 storage terminal for ship transportation [texte imprimé] / Ung Lee, Auteur ; Youngsub Lim, Auteur ; Sangho Lee, Auteur . - 2012 . - pp. 389–397. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 1 (Janvier 2012) . - pp. 389–397 Mots-clés : CO2  liquefaction  process Résumé : In this article, an intermediate CO2 storage system for long-distance ship transportation was modeled. The storage terminal links the continuous CO2 liquefaction process to discrete marine ship transportation and performs as a buffer between them. It is composed of four distinct processes: a CO2 input process, a storage tank and loading process, a recirculation process, and a BOG (boiled-off gas) reliquefaction process. The entire system should be operated as a liquid phase. Consequently, operation conditions, tank capacity, insulation specification, and streamflow rates play a major role in operating the storage terminal securely. The goal of this study is to design a base case of the storage terminal and propose its appropriate operation condition which makes the terminal operate with minimum operation energy. Results of the base case simulations are compared with improperly insulated systems on the pipeline and tanks that generate more BOG than the base case. The total operation energies of the base case and case studies are presented, and it turns out that approximately three times the operation energy is required if the system is not properly designed. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie200762f