Wadsworth, M. E.; roves, R. D. Trans. Soc. Min. Eng. A I M Perry, R. H.; Chllton, C. H. "Chemlcai Englneers' Handbook", 5th ed.; Szekeiy, J.; Themeiis. N. J. Wiley: New York, 1971; Chapter 17. Vlzsolyi, E. et al.Sieve trays have become popular contacting devices for mass and heat transfer applications because of their relative simplicity and low cost. As a result, much has been published in recent years on their hydraulic and mass transfer performance. However, little has appeared on improving contact performance by adding a shallow bed of packing on the trays. The hydraulic and mass transfer performance of sieve trays containing a 25-mm bed of a knitted mesh packing was studied for the Glrdier-Sulfide (GS) heavy water production process operating at 32 OC and 2.17 MPa. With packing, tray pressure drops increased, tray-to-tray entrainment decreased, and efficiency increased by 3 to 20 percentage points. The greatest efficiency gains occurred in the low gas flow range where the tray operated in the bubble regime.