Experimental Study on Postcombustion Systems including a Hollow Fiber Membrane and a Packed Column

Abstract

In this work, a comprehensive lab-scale carbon capture installation was established to study the separation performances of CO2/N2 systems for the postcombustion technology. Four kinds of mono-/two-stage carbon capture methods containing membrane separation and chemical absorption processes were investigated. The result shows that the CO2 capture performance of the one-stage membrane separation method (Memb) exhibits a profitable CO2 removal efficiency but defective CO2 concentration, while the one-stage chemical absorption method (Chem) indicates both CO2 removal efficiency and CO2 purity of more than 95.0% but suffers a regeneration heat of at least 2.7 MJ/t CO2. The CO2 purity of the two-stage membrane separation method (Memb-Memb) is 46.2% higher than the Memb method because of the additional membrane pretreatment. Two-stage methods have a superior gas recovery efficiency of over 99.0%, which is dramatically higher than the homogeneous Memb method. In addition, the investigation on the hybrid chemical absorption-membrane separation method (Memb-Chem) provides an alternative approach to reduce the mass transfer and solve the problems caused by an unequal mass flow distribution.