A fundamental model for the prediction of distillation sieve tray efficiency. 1. Database development

A mechanistic model has been developed for the prediction of sieve tray poi nt efficiency for both aqueous and hydrocarbon systems. A forerunner of the model was developed from fundamental relationships by Prado and Fair (Ind. Eng. Chem. Res. 1990, 29, 1031) and was based on gas-liquid transfer in sy stems predominantly air and water. The earlier model has now been modified and extended. Contacting on a sieve tray is considered analogous to gas-liq uid contacting in a mechanically agitated vessel, and supporting research h as been adapted to the tray-contacting case. Studies in bubble columns have provided information on bubble size distribution and bubble stability at h igh pressure; these studies coupled with isotropic flow theory have formed the basis for correlating bubble size distribution as well as the fraction of small bubbles in the sieve tray froth. New tray efficiency data taken on a semi-industrial scale have been combined with published data as well as new data released by Fractionation Research, Inc. to form a large database suitable for model testing. This work is covered in part 1. In part 2, deta ils of the new model will be presented along with comparisons of predicted and measured efficiencies. Predicted efficiencies were found to be within /-25% of the measured (or deduced) values of the same efficiency. Compariso ns are included showing the fit of the same data bank to the earlier model of Chan and Fair.