Study on the Fluid Dynamics Characteristics of Stirring-Box Tray

A patented tray called stirring-box tray has been developed and tested. A number of specially designed stirring-boxes are fixed over the collective sieve holes. The fluid mechanics characteristics of the tray,i.e. pressure drop, weeping, entrainment and liquid height in the downcomer, are determined on a test rig with 1000mm by air-water system at an atmospheric pressure. The experimental results are compared with those of the traditional sieve tray. It indicates that the stirring-box tray has the advantage of lower entrainment and bigger flux. The correlations for calculating the pressure drop of the stirring-box tray are derived from the experimental data. In addition, the liquid stream on the tray bed is pushed by the spurting liquid from the mouth of stirring-box with the same direction of liquid flow on the tray,which can reduce the liquid eddy and backmixing. Theoretically, being well mixed in the stirring-box with the liquid-phase, the vapor-phase leaving the stirring-box will approximately reach equilibrium with the liquid flowing from the box.As a result, the mass transfer efficiency of the tray might increase greatly.