| Titre : | A high temperature lithium orthosilicate - based solid absorbent for post combustion CO2 capture (2012) |
| Auteurs : | Robert Quinn, Auteur ; Ronald J. Kitzhoffer, Auteur ; Jeffrey R. Hufton, Auteur |
| Type de document : | Article : texte imprimé |
| Dans : | Industrial & engineering chemistry research (Vol. 51 N° 27, Juillet 2012) |
| Article en page(s) : | pp. 9320-9327 |
| Note générale : | Industrial chemistry |
| Langues : | Anglais |
| Tags : | Carbon dioxide Combustion Absorbent |
| Résumé : | Capture of carbon dioxide from combustion processes presents a unique and challenging technical problem arising from low CO2 partial pressures, high flow rates, and the presence of water vapor and reactive contaminants such as SO2. A series of solid sorbents were evaluated to determine suitability for postcombustion capture. A lithium orthosilicate (Li4SiO4)-based absorbent supplied by Toshiba Corporation was found to have the most promising properties. The absorbent reacts chemically with CO2 at elevated temperatures (550 °C) to form lithium carbonate (Li2CO3) and lithium metasilicate (Li2SiO3). The presence of water vapor was shown to greatly enhance CO2 absorption rates without affecting capacity. Breakthrough capacities of ∼5―6 mmol/g (22-26 wt %) were obtained using a "clean" synthetic flue gas containing 15% CO2 and 10% H2O in N2 at 550 °C. Experimental studies showed that the absorbent used in a fixed bed process will likely require a thermal swing process with absorption at 550 °C and regeneration at 650 °C. Even for the high capacity of the Li4SiO4-based absorbent, an alternative to conventional fixed bed technology will be required for practical postcombustion capture from coal-fired power plants. Processes that can shorten cycle times by rapidly heating and cooling vessels and/or sorbents will be needed, and possible alternatives are described. |
| ISSN : | 0888-5885 |
| En ligne : | http://cat.inist.fr/?aModele=afficheN&cpsidt=26132268 |
