The costs for industrial processes of separation in tray columns, both capital and current, are inverse to efficiency of the mass transfer between steam (gas) and liquid. For such type of equipment the separation efficiency improvement potential in related to organization of phase movement in the column.
The most efficient component separation is achieved upon perfect displacement by liquid and steam. By means of the customary technological regimes and contact devices it seems impossible to reach the desired result. But this problem can be solved by the mass exchange technology with separate phase movement (cyclic process), implemented as follows: lack of outflow of liquids to the trays vapor admission; lack of mixing of liquids in adjacent trays upon outflow of liquid. The perfect displacement effect is achieved by means of using of the coordinate system for changing of concentration of the volatile component on contact stage during the steam supply. It allows actually eliminating the mixture of liquid in the tray with various concentrations of high-volatile component. The mathematic modeling allowed offering theoretical stage model with perfect displacement with a trayed column for description of the mass transfer process with separate phase movement. Meanwhile analytically it was proved that the existing theoretical tray and perfect displacement theoretical tray are two extreme cases of hydrodynamic mass transfer regimes in the trays – perfect mixing and perfect displacement. Theoretical developments were implemented in special contact devices patented in numerous countries. Industrial implementation was held in Ukraine in food alcohol production. The first industrial column has been in operation for 6 years already. The tests showed the component separation efficiency improvement by 3 to 4 times, while the process power consumption reduced 1.5 to 2 times.
