Mass transfer performance of structured packings in a CO2 absorption tower

This paper studies the mass transfer performance of structured packings in the absorption of CO2 from air with aqueous NaOH solution. The Eight structured packings tested are sheet metal ones with corrugations of different geometry parameters. Effective mass transfer area and overall gas phase mass transfer coefficient have been measured in an absorption column of 200 mm diameter under the conditions of gas F-factor in 0.38–1.52 Pa0.5 and aqueous NaOH solution concentration of 0.10–0.15 kmol·m− 3. The effects of gas/liquid phase flow rates and packing geometry parameters are also investigated. The results show that the effective mass transfer area changes not only with packing geometry parameters and liquid load, but also with gas F-factor. A new effective mass transfer area correlation on the gas F-factor and the liquid load was proposed, which is found to fit experiment data very well.

Graphical abstractThe effective mass transfer areas of sheet corrugated structured packings were measured in a packing column about 1.2 m tall with an inside diameter of 200 mm, in which the height of packed section is 0.8 m. Air entered at the bottom of the column and flowed upward, while NaOH solution was pumped to the top of the column and flowed downward. The figure shows the effects of addendum angles on effective mass transfer areas of sheet corrugated structured packings. At α of 37.5°, when Fs = 0.76 Pa0.5 or 1.14 Pa0.5, packing with β of 90° has the largest effective mass transfer area. And the effect of α and β on the area was also changed by gas/liquid flow rates. Under most gas/liquid flow rates in this study, α = 30° and β = 75° were the best parameters.Figure optionsDownload full-size imageDownload as PowerPoint slide