Publikationsrepositorium - Helmholtz-Zentrum Dresden-Rossendorf

Optimal bubble generation for biological aeration process is currently under discussion. We studied bubble formation from a range of solid orifices, from 20 µm to 800 µm, submerged in water under constant flow condition. Scant experimental data is available within this range. We studied the change in the mechanism of bubble formation and detachment at different bubbling regimes. Moreover, the existing theoretical and empirical models for prediction of initial bubble size were evaluated according to the corresponding experimental data. A modified model for prediction of initial bubble size is proposed from the best fit of experimental results. Finally, we introduced another empirical model for prediction of optimal operation condition according to consumption of 95% oxygen uptake from air bubbles in water. In the later model, parameters such as pressure drop of the system, capacity of aeration basin, and available specific aeration area for oxygen transfer are adopted.