关键词: weeping;distillation;tray efficiency

Abstract: Experiments demonstrated that the weeping is mal-distributed and occurs mainly in a region
of traydeck next to the inlet weir. The amount of weeping in this region depends on the
weeping rate. On this basis, threetypes of weeping distribution are proposed. The effect of
mal-distributed weeping on the Murphree tray efficiencyis evaluated by using the three-
dimensional non-equilibrium mixing pool model, where the influences of the flowpattern and
the variation of Murphree point efficiency on a tray are taken into account. The calculated
resultsreveal that the extent of Murphree tray efficiency drop depends chiefly on the
degree of mal-distribution and thepercentage of weeping. It is also demonstrated that in
the determination of the lowest operating limit of vaporvelocity, the unfavorable effect of
mal-distributed weeping should be considered as an important factor and cannotbe ignored.

Key words: weeping, distillation, tray efficiency