Experimental studies on the hydrodynamics, mass transfer and reaction in bubble swarms with ultrafast X-ray tomography and local probes

The main focus of this project was the experimental investigation of hydrody-namics and mass transfer characteristics together with a chemical reaction in a bubble column at higher gas holdup. Experiments were performed for chemical absorption of CO2 in alkaline solution of different pH, at homogenous bubbly flow conditions and up to 17% gas holdup. Ultrafast electron beam X-ray to-mography (UFXCT) has been used to obtain local gas holdup data and bubble characteristics and a wire-mesh sensor was used to measure species concentra-tion fields in the liquid bulk. In addition, experiments with the reactive system FeII(edta)/NO were carried out and a new a fiber optical probe was employed for local measurement of product concentration in the bubble wake.