| The carbon dioxide (CO{dollar}sb2{dollar}) absorption process, using aqueous alkanolamine solutions, has been extensively used for several decades, but could be improved by using a more effective absorption solvent. 2-Amino-2-methyl-1-propanol (AMP) can probably be used as an absorption solvent instead of the conventional alkanolamine, monoethanolamine (MEA) with improvements in CO{dollar}sb2{dollar} absorption capacity and a reduction in corrosion. One limitation for the application of AMP is that its rate of absorption is appreciably lower than that of MEA. However, this limitation can be overcome by using structured packings as the absorber interior.; The possibility of using the structured packing was evaluated using CO{dollar}sb2{dollar} absorption into sodium hydroxide (NaOH) solution, since this is commonly used to characterize packing efficiency. The absorption of CO{dollar}sb2{dollar} into an aqueous solution of AMP was then investigated in order to determine the performance of the structured packing with this new solvent. The absorption experiments were performed in a 1.77 m high and 0.019 m diameter absorption column, packed with a laboratory structured packing, over a range of operating variables, i.e. up to 0.15 atm partial pressure of CO{dollar}sb2{dollar} 0.29-0.61 m{dollar}sp3{dollar}/m{dollar}sp2{dollar} s gas flow rate, 4.9-14.6 m{dollar}sp3{dollar}/m{dollar}sp2{dollar} h liquid flow rate, and 1.1-3.0 kmol/m{dollar}sp3{dollar} absorbent concentration. The performance of the packing is presented in terms of the volumetric overall mass transfer coefficient {dollar}rm Ksb{lcub}G{rcub}asb{lcub}v{rcub}{dollar}. The effects of the main operating variables, such as CO{dollar}sb2{dollar} partial pressure, liquid flow rate and liquid composition, on {dollar}rm Ksb{lcub}G{rcub}asb{lcub}v{rcub}{dollar} were also investigated. An empirical mass transfer correlation, including the effects of such variables, was developed for the CO{dollar}sb2{dollar}-AMP system.; The results indicate that the use of the structured packing can considerably improve the efficiency of CO{dollar}sb2{dollar} absorption into hindered amine AMP solution and makes this system extremely competitive with the conventional MEA-random packing system. (Abstract shortened by UMI.)... |
