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The operating parameters of a tray having new vortex contact devices for adiabatic and nonadiabatic fractionation are investigated. In the vortex device, the vapor moves through tangential channels of the vortex tray for adiabatic and nonadiabatic fractionation, acquires swirling motion, and disperses in the fluids, forming thereby a swirling gas-liquid layer where intense heat and mass transfer takes place. Such a tray design ensures a small fluid volume in the stage and intimate mixing of the gas-liquid mixture. The investigations showed high productivity and efficiency of the vortex tray in a wide gas (vapor) load variation range. The parameters of the swirling gas-liquid layer, such as height, gas content, angular velocity, hydraulic resistance, phase contact area, and coefficient of mass transfer are determined, and an equation is proposed for their calculation. The experimental investigations of the vortex tray efficiency for adiabatic and nonadiabatic fractionation demonstrated that mass transfer in the vapor phase is intensified in nonadiabatic conditions.

Vortex contact devices for gas introduction have been developed and studied. The devices make it possible to increase the gas and liquid loading on stages compared with valve and cap devices, to reduce the fluctuations of the gas–liquid medium on the liquid surface, and to increase the separation efficiency. Based on the experimental studies and numerical modeling, a scheme of liquid and gas motion at the stage was developed, and the velocity profiles during bubbling were calculated. The stage parameters were determined: hydraulic resistance, gas content, average surface diameter of bubbles, interphase surface area, efficiency, and mass transfer coefficients. The dependences for their calculation were presented. A vortex stage for the exhausting distillation column was designed, which provides a 1.5-fold reduction of metal consumption and increased efficiency at a velocity factor of up to 3 Pa0.5 and spray rate of 78 m3/(h m2) compared with the standard cap plate.

The hydraulic resistance of nine tangential swirlers with rectilinear and sectional channels is measured. A comparison of the hydraulic resistance coefficients of the different swirlers is and it is established that the structural parameters of the swirlers and Reynolds number together exert a significant influence on the hydraulic resistance. It is shown that the resistance coefficient increases with increasing width of the swirler channel gap due to a decrease in the gas velocity and an increase of the force of viscous friction. A relationship for calculating the resistance coefficient of the swirlers is obtained.

This article presents the results of experimental research and simulation of the hydraulic drag of tangential swirlers. Three types of swirler devices made with straight, profiled, and circular channel walls were studied within a wide range of design and process parameters. Simulation modelling on the Comsol Multiphysics platform was used to calculate hydraulic drag and determine the velocity and pressure fields. This allowed obtaining a dependence of the hydraulic drag coefficient of the investigated swirlers and identifying parameters affecting their hydraulic drag.

Thermal fractionation in a column with stages made of horizontally mounted trays is studied. Absorption and fractionation are used as examples to show that mass transfer can be enhanced if the liquid on the trays is rotated. It is established that the efficiency increases if the speed and the concentration of volatile component in the mixture increase because the liquid and vapor phases are mixed better. The overall efficiency is improved by two and more times during thermal fractionation in a column with 10 contact stages.

This paper proposes a mechanism of gas bubble formation in a down-flowing liquid film as a result of reduced pressure in circulation zones of threaded roughness recesses. Simulation modelling on the Comsol Multiphysics software was used to calculate circulation loops, liquid velocities, and pressure. Thus, the accepted of gas bubble formation was justifying. We experimentally determined gas content along film thickness and its average value, and proposed an equation for calculating gas content along liquid layer thickness. The effect of gas content on the average thickness of a liquid film, as well as its heat and mass transfer, was confirmed.

The thermal rectification method, which comprises the condensing of vapors on steps and subsequent exposure of the heat flow on condensate before it is introduced into the falling reflux, has been studied. The results of the study of strengthening ethanol–water mixture upon the condensation of vapors on the heat-transfer surface have been presented. The basic parameters of the process have been revealed, which ensure the strengthening of the mixture on the stage upon condensate evaporation, and the empirical relationship for determining the effectiveness has been obtained. The studies of the thermal rectification of the ethanol–water mixture have been performed in a column with 24 contact stages made of horizontal plates, and conditions have been established that provide the greatest efficiency. The evaluation of thermal rectification contribution to the overall efficiency of the stage is performed that allows one to intensify the process by up to four times.

The results of studying the process of distillation in a column with 21 vortex contact stages have been reported. The partial condensation of an ascending ethanol–water mixture vapor at the contact stages has been shown to intensify the mixture distillation process by threefold compared to adiabatic distillation. The process parameters that intensify heat and mass transfer in thermal distillation have been established. Some relationships for estimating the efficiency of a vortex contact stage have been derived.

Diabatic units having heat exchanger tubes functioning as dephlegmators on trays, which allow to reduce the cost of the process, are considered. It is shown that the most efficient approach is to arrange heat removal with the film flow of the heat carrier in the diabatic column dephlegmator. Heat transfer intensification in a gravitationally flowing film, as well as to in an upward and downward parallel flow during the heating and boiling of the heat carrier was analyzed. Dependences for determining the value of the heat transfer factor are presented.