IMPROVEMENT OF CONTACT DEVICES OF THE BUBBLING TRAY

Abstract

The results of a study of hydrodynamics and mass transfer on bubbling-type trays with valve, valve-vortex and vortex contact devices are presented. By means of experimental studies and numerical modeling, the velocity fields of liquid and gas, as well as the structure of the gas-liquid layer on the tray are determined. The dependence of the relative amplitude of fluctuations in the level of the gas-liquid layer on the tray by the gas flow rate when placing various types of contact devices on it is obtained. The average surface diameter of gas bubbles is determined and the mechanism of their accumulation in the liquid on the tray is proposed. The relationship between the velocity of liquid circulation on the plate and the size of gas bubbles entrained by the circulation flow has been confirmed. The pressure drop of the investigated contact devices was measured and the value of the hydraulic resistance coefficient was determined. Experimental data on the intensity of mass transfer and efficiency on tray are presented. Specific fluid flow rates have been established to ensure high efficiency.It is shown that the most efficient, liquid- and gas-carrying capacity is possessed by trays with vortex cantate devices having a low amplitude of oscillation of the gas-liquid layer and a large interfacial surface. This is due to an increase in the energy dissipation of gas jets in the liquid on the tray, the uniform distribution of gas bubbles and the presence of rotational motion of the gas-liquid layer.