A stirred bubble column contactor is investigated using of computational fluid dynamics (CFD) and population balance equations. For the simulation, the Euler-Euler model is applied which accounts for the interactions between the phases by experimentally derived correlations. Therefore, the resistance coefficient of singe bubbles is measured using a single bubble test rig keeping the bubble in a plane using a counter-current flow. The resulting drag coefficient for spherical bubbles could be described by literature correlations. The system allows further measurements of the mass transfer at a stagnant bubble. Computational fluid dynamics population balance simulations of the stirred bubble column contactor show good agreement between the simulated bubble size and experimental data.