An intensified low-energy ultrasonic plug reactor for CO2 desorption from single and novel blended absorbents

Ultrasound as an efficient emerging technology for CO2 desorption enhancement has attracted great attention in recent years. In the present study, a mini-plug reactor was equipped with a 28 kHz ultrasound transducer and employed for CO2 stripping from different amine-based solutions. First, 30 wt% aqueous solutions of MEA, DEA, DIPA and MDEA were investigated under the effect of desorption temperature and flow rate of the solution. 26.4% energy saving and around 70% enhancement in desorption was reached for MEA at 55℃ using ultrasound irradiation. Some novel tri-solvent blends were also studied in the optimum temperature. Among four blended amine solutions, new aqueous solution of MEA+DIPA+AMP showed the maximum desorption rate of 84.2% and minimum regeneration energy of 2.7 MJ/kgCO2 using the designed ultrasound-equipped plug reactor. It was concluded that CO2 desorption from the MEA+DIPA+AMP blend could reduce required energy consumption by around 35% compared to 30 wt% MEA using conventional method. The present study provided an efficient intensified desorber as well as a kind of tri-solvent blend as a brilliant system for CO2 capture process at lower temperature than conventional.