Experimental study on hybrid MS†CA system for post†combustion CO2 capture

A lab†scale hybrid membrane separation†chemical absorption (MS†CA) system for a post†combustion process was implemented by combining a hollow†fibre membrane module and a packed column in series. A solution†diffusion model and double†film theory were adopted to investigate the mass†transfer performance of membrane separation and the chemical absorption process. To determine optimal operational conditions, experiments were conducted to investigate the mass transfer characteristics and CO2 removal of both mono†staged systems. A hybrid MS†CA method was studied to measure coupling characteristics and CO2 removal performance of the system. It was found that increasing the pressure and the temperature of the feed gas enhanced the CO2 diffusion property of the membrane module. For a packed column, mass transfer and carbon capture is affected by the liquid†to†gas ratio; TMEA = 40°C is considered the optimal condition. For a hybrid MS†CA system, the optimal CO2 removal efficiency can reach 99.49% at the condition of Pf = 1 MPa, wMEA = 10 wt%. Improving the feed†gas pressure will increase the CO2 absorption rate of the overall hybrid system. Compared with the mono†staged method, the hybrid MS†CA system has a higher stability and efficiency for the post†combustion process, especially at a relatively low feed†gas pressure. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd.