Carbon dioxide capture by blended alkanolamines in rotating packed bed

Abstract The capture of CO2 from a 10 vol% CO2 gas by chemical absorption with aqueous solutions containing 30 wt% of single and mixed monoethanolamine (MEA), 2-(2-aminoethylamino)ethanol (AEEA), piperazine (PZ), and 2-amino-2methyl-1-propanol (AMP) in a rotating packed bed (RPB) was studied. The RPB had an inner diameter of 7.6 cm, an outer diameter of 16 cm, and a height of 2 cm. The CO2 capture efficiency was found to increase with increasing temperature in a range of 303 to 333 K. It was also found to be dependent on rotating speed, gas flow rate, and liquid flow rate. The 30 wt% mixed alkanolamine solutions containing MEA or AEEA with at least 10 wt% PZ were the appropriate absorbents compared with the single alkanolamine and the mixed alkanolamine solutions containing AMP. A higher portion of PZ in a mixture was more favourable to CO2 capture. Because of short contact time in a RPB, alkanolamines with high reaction rate with CO2 are suggested to use. For the solutions containing 15 wt% MEA or AEEA and 15 wt% PZ, the highest gas flow rate allowed to achieve a capture efficiency more than 90% were 30 L/min at a solution of 100 mL/min and 50 L/min at a solution of 300 mL/min. The corresponding height transfer units were found to be less than 2.0 cm, significantly lower than those in a conventional packed bed absorber.

[1]  Meng-Hui Li,et al.  Heat Capacity of Alkanolamine Aqueous Solutions , 1999 .

[2]  Gary T. Rochelle,et al.  Absorption of carbon dioxide into aqueous piperazine: reaction kinetics, mass transfer and solubility , 2000 .

[3]  H. Svendsen,et al.  Kinetics of the reaction of carbon dioxide with aqueous solutions of 2-((2-aminoethyl)amino)ethanol , 2007 .

[4]  Chung-Sung Tan,et al.  Reduction of CO2 concentration in a zinc/air battery by absorption in a rotating packed bed , 2006 .

[5]  Sarat Munjal,et al.  Mass-transfer in rotating packed beds—I. Development of gas—liquid and liquid—solid mass-transfer correlations , 1989 .

[6]  Chung-Sung Tan,et al.  Absorption of carbon dioxide with piperazine and its mixtures in a rotating packed bed , 2006 .

[7]  Erdogan Alper,et al.  Reaction mechanism and kinetics of aqueous solutions of 2-amino-2-methyl-1-propanol and carbon dioxide , 1990 .

[8]  Hallvard F. Svendsen,et al.  Heat of Absorption of Carbon Dioxide (CO2) in Monoethanolamine (MEA) and 2-(Aminoethyl)ethanolamine (AEEA) Solutions , 2007 .

[9]  Asit K. Saha,et al.  Kinetics of absorption of CO2 into aqueous solutions of 2-amino-2-methyl-1-propanol , 1995 .

[10]  G. G. Stokes "J." , 1890, The New Yale Book of Quotations.

[11]  Partha S. Goswami,et al.  Process Intensification in Rotating Packed Beds (HIGEE): An Appraisal , 2004 .

[12]  A. Henni,et al.  Molar Heat Capacity of Various Aqueous Alkanolamine Solutions from 303.15 K to 353.15 K , 2007 .

[13]  Gary T. Rochelle,et al.  Thermodynamics of aqueous potassium carbonate, piperazine, and carbon dioxide , 2005 .

[14]  Gary T. Rochelle,et al.  Kinetics of Carbon Dioxide Absorption into Aqueous Potassium Carbonate and Piperazine , 2006 .

[15]  H. Hikita,et al.  Absorption of carbon dioxide into aqueous monoethanolamine solutions , 1979 .

[16]  Colin Ramshaw,et al.  Carbon dioxide absorption and desorption in aqueous monoethanolamine solutions in a rotating packed bed , 2007 .

[17]  Chia-Chang Lin,et al.  Removal of carbon dioxide by absorption in a rotating packed bed , 2003 .

[18]  Ahmed Aboudheir,et al.  Kinetics of the absorption of CO2 into mixed aqueous loaded solutions of monoethanolamine and methyldiethanolamine , 2006 .

[19]  Amit Chakma,et al.  CO2 capture processes — Opportunities for improved energy efficiencies , 1997 .