A supposedly rigorous tray efficiency model requires a large amount of input data:
• detailed tray geometry
• physical properties of the liquid and vapor phase
• operating conditions
• thermodynamic information
From such information, mass transfer coefficients, interfacial area, froth height, bubble regimes, horizontal back mixing, entrainment, weeping etc. can be derived, all of which are required to calculate the Murphree tray efficiency in a rigorous manner.
In sharp contrast to the considerable effort required to obtain all of this information collected, the well-known O’Connell correlation to estimate the section efficiency has been used quite successfully. Perhaps due to its simplicity, it is the most often applied method.
O’Connell’s method is an empirically obtained correlation to determine efficiencies of trays that has been widely applied in industry and has demonstrated applicability to many distillation processes. O’Connell’s simple method has survived all attempts at being replaced by more rigorous models. This paper presents a simple theoretical but fundamentally sound approach that achieves results equivalent to O’Connell’s correlation.