Intensifying the Absorption of CO2 in Water Using a Static Mixer; Part II: Effect of Reactor Design

An attempt to intensify the physical absorption of CO2 in water was undertaken in this work by means of using a tubular reactor equipped with screen-type static mixers. Four different screen geometries in two distinct reactor designs were tested for impact on the volumetric mass transfer coefficient, kLa, while changing flow rates and gas holdups. Results showed that the limits of intensification were reached and the system became limited by the reaction kinetics and not mass transfer. From a hydrodynamic point of view, the finer meshes rendered the largest kLa values, while from an energy perspective, the coarsest woven mesh rendered the best energy utilization efficiency. Depending on the employed screen geometry, kLa values as high as 0.899 s–1 could be reached using 0.0139 kWh/tonne of processed liquid, while changing the screen geometry can result in kLa = 0.774 s–1 at 0.0062 kWh/tonne.