A Study on Sieve Tray Lower Operating Limit

Sieve trays are widely used fractionating devices in separation and purification industries involving tray towers. According to the importance of trays, it is vital to predict lower operating range limits for such gas-liquid contacting devices. Weeping phenomenon observed in bubbling regime and occurs at low vapor flow rates. The experimental set up includes a 1.22 m diameter column with two test trays and two chimney trays. Hydraulic parameters and weeping rates were measured in sieve trays with 7.04 percent holes area. The model considers the tray's thickness and is able to calculate the dry tray pressure drop, total pressure drop, clear liquid height, froth height, and weeping rate simultaneously. Predicted results were in good agreement with the experimental data. This model is able to predict the trend of weeping even in higher rates where efficiency is reduced significantly.