Low-Concentration CO2 Capture from Natural Gas Power Plants Using a Rotating Packed Bed Reactor

Abstract

A rotating packed bed (RPB) was employed as a highly effective reactor to intensify CO2 capture in a green and natural amino acid salt absorbent, potassium sarcosine (KSAR), from the flue gas containing a low CO2 concentration. Experimental results show that a good CO2 capture performance, presented in terms of CO2 capture efficiency and overall volumetric mass transfer coefficient (KGa), can be obtained at a low CO2 concentration of 2–6%. CO2 capture efficiency could reach higher than 80% at a relatively high gas–liquid ratio, with CO2 loading up to 0.17 mol of CO2/mol of KSAR. Comparison results with a packed column show that a RPB can obtain higher CO2 capture performance with a smaller device size. Moreover, a mathematical model was developed to describe the mass transfer process in a RPB. Calculated values of KGa agreed well with experimental data, with a deviation within ±25%, and the tendency of the CO2 concentration at the outlet of the RPB can be well-predicted under a high liquid flow rate and h...