PREDICTION OF PACKED SIEVE TRAY EFFICIENCY IN DISTILLATION

The mass transfer efficiencies of a packed sieve tray and a sieve tray have been measured for the distillation of six binary mixtures. These mixtures cover a wide range of physical properties. The efficiency of the sieve tray was found to increase significantly by adding a layer of mesh packing on the tray which can be attributed to a higher interf acial area, longer vapour/liquid contact time (i.e. higher froth heigh t) and a lower liquid backmixing. An efficiency model for the packed s ieve tray was developed by combining a fundamental point efficiency mo del and the correlation of liquid mixing for the packed sieve tray. Th e point efficiency model is based on the analysis of the dispersion st ructure and zone contribution on the tray and experimentally measured values of tray efficiency in the distillation of six binary mixtures. The predicted point efficiencies for packed sieve tray agree with meas ured values with an average error of 3.9%.