Geometric factors affecting CO2 separation in a supersonic separator

Abstract

The current work evaluates a potential carbon separation approach with swirl flows and spontaneous condensation. Euler-Euler model is established to depict the spontaneous condensation. By combining Euler-Lagrange model and Euler-Euler model, the droplet motion behavior is predicted, and the influence of separator structure including swirl generator and gap length on the separation efficiency of CO2 is quantified. The flue gas expands under pressure to create a non-equilibrium system, which leads to the emergence of CO2 condensation nuclei. On the surface of nuclei, metastable molecules aggregate and promote the growth of CO2 droplets. Based on the force on droplets, the droplet behavior can be separated into three categories: impacting the straight tube wall, entering the collector and entering the diffuser. When the angle of swirl generator and gap length rises by 315° and 3.75mm respectively, the separation efficiency rises by 60.3% and 48.6%, respectively.