The formation and motion of gas bubbles, and more especially the size of the bubbles formed, are important factors in many chemical engineering processes. In the present paper we describe the influence of vibration on bubble size and establish that the energy transferred from the vibrating channel to the bubbles is well correlated to the speed of vibration. We present a new model for determining and controlling bubble size and report results of experiments showing a high degree of compatibility between experimental results and the mathematical model and confirming the suitability of the model for engineering design applications.

Gas bubble motion characteristics and bubble size are important factors in various technological processes involving the interaction between liquid and gaseous systems. The present work studies the effect of vibration fields on the characteristics of bubble motion and bubble size. Bubble retention time in the liquid (rise velocity) and bubble mean diameter were chosen as main parameters effecting the oxygen mass transfer rate. A device for mechanical vibration of the aerated liquid was used. The influence of the device design parameters on the chosen bubble parameters is studied experimentally and discussed in this work. The results obtained show the possibility of controlling bubble retention time and bubble size by employing vibration fields. Thus, by applying rather simple techniques, one can considerably improve the process of liquid oxygenation.

Gas transfer efficiency during absorption is an important factor in various technological processes involving the interaction between liquid and gaseous systems. It is known that gas bubble motion characteristics strongly affect the efficiency of mass transfer during gas absorption. A device for mechanical vibration of an aerated liquid was designed, based on a cylindrical column filled up with tab water and a plate oscillating in the vertical direction. The goal of the present study is to investigate the effect of vibration parameters such as amplitude, frequency and form of the applied signal on the efficiency of the oxygenation process. Bubble residence time in the liquid and bubble depth of submergence related to the oscillating plate surface were chosen as main parameters for measurements. Furthermore, experiments were conducted to study the effect of the design parameters of the vibrating plate on bubble motion characteristics. The resultant data show that bubble residence time and depth of submergence can be controlled by changing the amplitude, the frequency and the form of the vibration field applied.

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