A mathmatical model for predicting Murphree tray efficiency was proposed with consideration of the mal- distributed weeping

non- uniform liquid flow

unequal directional eddy diffusivity and variation of Murphree point efficiency across the tray. Two typical cases of mal- distributed weeping in industrial columns were used to illustrate how the Murphree tray efficiency could be further decreased in comparison with uniform weeping.The calculated results showed that the extent of Murphree tray efficiency drop depended on the degree of mal-distribution of weeping

especially when weeping was intensified near the inlet weir as often appeared on large trays due to higher hydrostatic liquid head . The unfavorable effect of mal- distributed weeping should not be ignored in setting up the lowest limit of vapor velocity.