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Abstract: This work presents the modeling and experimental investigation on absorption of CO2 by Benfield solution in rotating packed bed (RPB). A model was established to illustrate the mechanism of gas–liquid mass transfer with reactions in RPB at higher gravity level. Experiments were carried out at various rotating speeds, liquid flow rates, gas flow rates and temperatures in RPB, with Benfield solution as the absorbent. The validity of this model was demonstrated by the fact that most of the predicted y o (mole fraction of CO2 in outlet gas) agreed well with the experimental data with a deviation within 10%. The presented profile of K Ga (gas-phase volumetric mass transfer coefficient) along the radial direction of the packing could reasonably explain the end effect in RPB. As a result, this model is reliable in describing the removal of CO2 by Benfield solution in RPB at higher gravity level. [Copyright &y& Elsevier]

Stainless steel wire mesh packing is widely used forexperimental and industrial applications in rotating packed beds (RPBs)for gas–liquid contacting because it has a higher mass-transferperformance than other conventional packings. In this work, the gas–liquideffective interfacial area of a conventional RPB was studied witheight types of stainless steel wire mesh packings, consisting of fourdifferent stainless steel fibers. Gas–liquid chemisorptionwith CO2in NaOH solution was employed to measure the effectiveinterfacial area for all types of packings with different rotationalspeeds and gas–liquid ratios. An empirical correlation thattakes the effects of the fiber diameter and opening size of the wiremesh into consideration was proposed for the calculation of the gas–liquideffective interfacial area of stainless steel wire mesh packings ina conventional RPB. [ABSTRACT FROM AUTHOR]

In this work, gas–liquid mass transfer characteristics,such as effective interfacial area (ae) and liquid side mass transfer coefficient (kL), were investigated in a rotating packed bed (RPB) contactorwith 5 novel rotors equipped with blades in the packing section and1 conventional rotor without blades and fully filled with the samepacking. The chemisorption of CO2into a NaOH solutionwas used to evaluate aeand kLwithin each rotor of the RPB. The experimental resultsindicate that the rotors with blades can significantly intensify themass transfer process at all rotational speeds, over a range of gas–liquidratios. The mass transfer rate achieved within these novel rotorswas between 8% and 68% higher in comparison with the conventionalrotor. A model based on the Danckwerts surface renewal theory wasdeveloped to calculate the liquid side volumetric mass transfer coefficient(kLae) inthe rotor. The experimentally obtained values of kLaeare in agreement withmodel predictions within ±15%. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mesh packings with controllable cross-sectional areas were applied in RPB. • CO 2 absorption with amine solutions including DETA and PZ were studied. • CO 2 absorption efficiency of CONC-9 exceeded 17.1% than that of the COII-9. • The K G a/△P W of CONC-9 was larger by 48.6% than that of the COII-9. A rotating packed bed (RPB), as one of the typical HiGee reactors, has achieved extensive praise in CO 2 capture fields. In this work, the novel mesh packings with controllable cross-sectional areas (CSAs) were applied to intensify the CO 2 absorption process in an RPB, as well as combining with the blended aqueous amine solutions including diethylenetriamine (DETA) and piperazine (PZ). The gas pressure drop and CO 2 absorption performance of various packings were investigated. Different operating conditions including rotational speed (400–2400 r/min), liquid flow rate (10–35 L/h), gas flow rate (900–2400 L/h), and CO 2 molar fraction in gas inlet (2–12%) were considered. The results exhibited that the rise in gas pressure drop of concentric packing with constant CSA (CONC-9) relative to conventional coiled packing with increasing CSA (COII-9) was less than 10% on average. Meanwhile, the CO 2 absorption efficiency of CONC-9 exceeded 17.1% on average than that of COII-9. For further comparison, the ratio of mass transfer coefficient to gas pressure drop in the wet RPB (K G a/ △ P W) was analyzed. The K G a/ △ P W of CONC-9 was 48.6% larger on average than that of COII-9. The average mass transfer coefficient and height of mass transfer unit of CONC-9 reached up to 16.7 kmol∙kPa−1∙m−3∙h−1 and 0.013 m, respectively. Overall, it is a viable way to adopt the packing with constant CSA to intensify the CO 2 absorption in RPBs. [ABSTRACT FROM AUTHOR]

End effect is a significant phenomenonin a rotating packed bed(RPB). The mass transfer accomplished in the end zone can be one magnitudehigher than what is achieved in the bulk zone of the packing. In orderto make full use of the end effect, a novel multiliquid-inlet rotatingpacked bed (MLI-RPB) was developed, which artificially created theextra end zones in the bulk zone along the radial direction of therotor. The effective interfacial area (a) and liquid-sidevolumetric mass-transfer coefficient (kLa) of the MLI-RPB were measured using a system ofCO2chemisorption into NaOH solution. Mass-transfer experimentswere also conducted in a traditional RPB with the same size as theMLI-RPB. Compared with the traditional RPB, higher values of aand kLawereobtained in the MLI-RPB, showing a great potential for the industrialapplications. [ABSTRACT FROM AUTHOR]