Removal of Carbon Dioxide by Alkanolamines Solution in a Cross-flow Rotating Packed Bed

• Main Authors: Yu Hong Lin, 林俞宏
• Other Authors: C. C. Lin
• Format: Others
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/07742845608084610711

碩士 === 長庚大學 === 化工與材料工程研究所 === 97 === The removal of CO2 from a 10 vol% CO2 gas by chemical absorption with 30 wt% alkanolamine solutions containing monoethanolamine　(MEA),　piperazine　(PZ),　and　2-amino-2 -1-propanol (AMP) in the cross-flow rotating packed bed (RPB) was investigated. The cross-flow RPB had an inner radius of 2.4 cm, an outer radius of 4.4 cm, and an axial length of 12 cm. The CO2 removal efficiency was found to increase with increasing rotor speed, liquid flow rate and inlet liquid temperature. However, the CO2 removal efficiency decreased with gas flow rate. Also, the CO2 removal efficiency was found to be independent on inlet gas temperature. The 30 wt% alkanolamine solutions containing PZ with MEA were the appropriate absorbents compared with the single alkanolamine (MEA, AMP) and the mixed alkanolamine solutions containing AMP with MEA. A higher portion of PZ in alkanolamine solutions was more favorable to CO2 removal. Owing to less contact time in the cross-flow RPB, alkanolamines having high reaction rates with CO2 are suggested to be used. For the mixed alkanolamine solution containing 12 wt% PZ and 18 wt% MEA, the highest gas flow rate allowed to achieve the CO2 removal efficiency more than 90% at a liquid flow rate of 0.54 L/min was of 29 L/min. The corresponding height transfer unit (HTU) was found to be less than 5.0 cm, lower than that in the conventional packed bed.