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Постійне посилання колекціїhttps://dspace.nuft.edu.ua/handle/123456789/7522
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Документ Cyclic rectification technology in alcohol production(2019) Buliy, Yuri; Shiyan, Peter; Kuts, Anatoly; Melnyk, IrynaAlternate changing of the steaming periods and liquid overflow allows to intensify mass transfer between liquid and steam and to reduce the specific consumption of heating steam in the process of separation of multicomponent mixtures. The authors propose a technology for rectification, which involves the cyclic motion of the liquid without interrupting of the supply of heating steam and the construction of a rectification column for its implementation. The purpose of the work was to research the effectiveness of the proposed technology in the process of rectification of alcohol-containing fractions and to establish the specific flow rate of steam in the impurity concentration column. The investigations were carried out in the production conditions of the Chudniv branch of SE “Zhytomyr liquor producer ”. To ensure a cyclic mode, the column was equipped with movable liquid transfer devices connected to actuating mechanismes, which acted according to the controller program, and perforated (scale-shaped) trays. The primary task was to determine the hydrodynamic mode of operation of the contact devices - the lower and upper the critical vapor velocity of at which the liquid is retained on the plates and there is its entrainment. It is established that the vapor velocity in the free section of the column can reach 1.2 m/s or more, and in the openings of the scales must exceed the first critical velocity of 6.5-7.5 m/s. The weeping of the tray occurs at the vapor velocity in the holes of 1.5-1 m/s. It is experimentally proved that in the process of rectification of alcohol-containing fractions, the main impurities are removed completely, the degree of extraction of higher fusel alcohols is increased by 38%, methanol - by 15.6%, the multiplicity of concentration of the main impurities is increased by 25%, the higher alcohols - by 40%, methanol – by 34%, acrolein – by 36%. The costs of heating steam are reduced by 30% compared to typical installations and do not exceed 13 kg / dal of absolute alcohol introduced with feed. Exempted from the key impurities the bottom liquid of the impurity concentration column should be used for hydroselection in the purifying column.Документ Understanding process intensification in cyclic distillation systems(2011) Maleta, Vladimir; Kiss, Anton; Taran, Vitaly; Maleta, BogdanThe most effective separation possible in distillation columns takes place in the hydrodynamic regime where there is perfect displacement of the liquid and vapor streams. This can be achieved in distillation equipment with separate phase movement (SPM). Such an innovative route for process intensification in distillation is called cyclic distillation. The required process conditions are the lack of liquid outflow from the tray during vapor admission and the lack of liquid mixing in adjacent trays upon outflow of liquid. Remarkably, the throughput of such a column that operates in a controlled cycle mode is two or more times higher than the throughput reachable with conventional operation, at equivalent separation performance. In this study, a theoretical stage model with perfect displacement is proposed and the theory of the process working lines is developed. An adequate mass transfer model is also described along with the mode of calculation of tray columns operating in the cyclic operation mode. Sensitivity analysis was used to determine the effect of the key model parameters. The theoretical developments were implemented at industrial scale and subsequent testing showed an increase in the separation efficiency of 2-3 times as compared to the standard process.Документ Hydrodynamics of liquid flow in the model of theoretical stage with perfect displacement(2011) Maleta, Vladimir; Taran, Vitaly; Maleta, BogdanPursuant to Lewis' work [1], the use of combinations of various hydrodynamic models of liquid and vapor phases enhances the efficiency of component separation on the tray. The greatest effect is achieved upon perfect displacement by liquid and vapor and sing-direction movement of liquid on adjacent contact degrees. In such conditions the efficiency of Murphy's tray may significantly exceed the local efficiency and reach 200-300% Cannon [2] suggested the way of phase interaction, for which during the passage of vapor through the column the liquid doesn’t overflow from tray to tray and upon liquid overflow it doesn't mix on adjacent trays (cyclic process). In a series of works [3, 4] it was shown that upon comparison of stationary and cyclic process both by the time of mass transfer on the tray and by the phase interaction nature the cyclic process is similar to the stationary process upon sing-direction movement of liquid on adjacent contact levels and perfect displacement by liquid and vapor. A mathematical model of the hydrodynamic processes occurring in a periodic cycled plate column is developed and experimentally confirmed.